阅读说明：本技术 聚酰胺和聚酰胺组合物 (Polyamide and polyamide composition ) 是由 关口健治 南谷笃 大矢延弘 金井诗门 重松宇治 于 2019-08-23 设计创作，主要内容包括：本发明涉及一种聚酰胺和含有该聚酰胺的聚酰胺组合物,该聚酰胺为具有二羧酸单元和二胺单元的聚酰胺,超过40摩尔％且100摩尔％以下的该二羧酸单元为萘二甲酸单元,60摩尔％以上且100摩尔％以下的该二胺单元为支链状脂肪族二胺单元和任选结构单元的直链状脂肪族二胺单元,且相对于该支链状脂肪族二胺单元与该直链状脂肪族二胺单元的合计100摩尔％,该支链状脂肪族二胺单元的比例为60摩尔％以上。(The present invention relates to a polyamide and a polyamide composition containing the polyamide, wherein the polyamide is a polyamide having a dicarboxylic acid unit and a diamine unit, more than 40 mol% and not more than 100 mol% of the dicarboxylic acid unit is a naphthalenedicarboxylic acid unit, not less than 60 mol% and not more than 100 mol% of the diamine unit is a branched aliphatic diamine unit and a linear aliphatic diamine unit which is an optional structural unit, and the proportion of the branched aliphatic diamine unit is not less than 60 mol% relative to 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.)

1. A polyamide which is a polyamide A having a dicarboxylic acid unit and a diamine unit,

more than 40 mol% and 100 mol% or less of the dicarboxylic acid units are naphthalenedicarboxylic acid units,

the diamine unit is a branched aliphatic diamine unit and a linear aliphatic diamine unit having an optional structural unit, and the proportion of the branched aliphatic diamine unit is 60 mol% or more based on 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.

2. The polyamide according to claim 1, wherein the proportion of the branched aliphatic diamine unit is 60 mol% or more and 99 mol% or less with respect to 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.

3. The polyamide according to claim 1, wherein the proportion of the branched aliphatic diamine unit is 80 mol% or more and 99 mol% or less with respect to 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.

4. The polyamide according to any one of claims 1 to 3, wherein the branched aliphatic diamine unit has 4 or more and 18 or less carbon atoms.

5. The polyamide according to any one of claims 1 to 4, wherein the branched aliphatic diamine unit is a structural unit derived from a diamine having at least 1 kind selected from a methyl group and an ethyl group as a branch.

6. The polyamide according to any one of claims 1 to 5, wherein the branched aliphatic diamine unit is a structural unit derived from a diamine having a branch at least one of a carbon atom at the 2-position and a carbon atom at the 3-position, when a carbon atom to which any one of the amino groups is bonded is the 1-position.

7. The polyamide according to any one of claims 1 to 3, wherein the branched aliphatic diamine unit is a structural unit derived from at least 1 diamine selected from the group consisting of 2-methyl-1, 5-pentanediamine, 3-methyl-1, 5-pentanediamine, 2-methyl-1, 8-octanediamine and 2-methyl-1, 9-nonanediamine.

8. The polyamide according to any one of claims 1 to 7, wherein the number of carbon atoms in the linear aliphatic diamine unit is 4 or more and 18 or less.

9. The polyamide according to any one of claims 1 to 7, wherein the linear aliphatic diamine unit is a structural unit derived from at least 1 diamine selected from the group consisting of 1, 4-butanediamine, 1, 5-pentanediamine, 1, 6-hexanediamine, 1, 7-heptanediamine, 1, 8-octanediamine, 1, 9-nonanediamine, 1, 10-decanediamine, 1, 11-undecanediamine, and 1, 12-dodecanediamine.

10. A polyamide composition comprising the polyamide A as claimed in any one of claims 1 to 9.

11. The polyamide composition of claim 10 further comprising a polyolefin B1.

12. The polyamide composition according to claim 11, which contains the polyolefin B1 in an amount of 1 to 100 parts by mass based on 100 parts by mass of the polyamide a.

13. Polyamide composition according to claim 11 or 12, wherein the polyolefin B1 is at least 1 selected from the following B1-1 to B1-5:

b1-1 alpha-olefin copolymer

b1-2 copolymer of at least 1 selected from ethylene, propylene and alpha-olefin having 4 or more carbon atoms and at least 1 selected from alpha, beta-unsaturated carboxylic acid, alpha, beta-unsaturated carboxylic acid ester and alpha, beta-unsaturated carboxylic acid anhydride

b1-3 ionomer of b1-2

b1-4 copolymer of aromatic vinyl compound and conjugated diene compound

b 1-5A polymer obtained by modifying at least 1 selected from the group consisting of b1-1 to b1-4 with an unsaturated compound having at least 1 selected from the group consisting of a carboxyl group and an acid anhydride group.

14. The polyamide composition according to claim 10, further comprising an organic heat stabilizer B2.

15. The polyamide composition according to claim 14, wherein the organic heat stabilizer B2 is contained in an amount of 0.05 to 5 parts by mass based on 100 parts by mass of the polyamide a.

16. The polyamide composition according to claim 14 or 15, wherein the organic heat stabilizer B2 is at least 1 selected from the group consisting of a phenol-based heat stabilizer B2-1, a phosphorus-based heat stabilizer B2-2, a sulfur-based heat stabilizer B2-3, and an amine-based heat stabilizer B2-4.

17. The polyamide composition of claim 10 further comprising a copper compound B3 and a metal halide B4.

18. The polyamide composition according to claim 17, wherein the copper compound B3 is contained in an amount of 0.01 to 1 part by mass based on 100 parts by mass of the polyamide a.

19. The polyamide composition according to claim 17 or 18, wherein the copper compound B3 is at least 1 selected from the group consisting of copper iodide, copper bromide and copper acetate.

20. The polyamide composition according to any one of claims 17 to 19, wherein the metal halide B4 is contained in an amount of 0.05 to 20 parts by mass based on 100 parts by mass of the polyamide a.

21. The polyamide composition of any one of claims 17-20, wherein the metal halide B4 is at least 1 selected from potassium iodide and potassium bromide.

22. The polyamide composition according to claim 10, further comprising a halogen-based flame retardant B5.

23. The polyamide composition according to claim 22, wherein the halogen-based flame retardant B5 is contained in an amount of 5 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the polyamide a.

24. The polyamide composition according to claim 22 or 23, wherein the halogen based flame retardant B5 is a bromine based flame retardant B5-1.

25. The polyamide composition of claim 24, wherein the brominated flame retardant B5-1 is brominated polystyrene.

26. The polyamide composition according to any one of claims 22 to 25, further comprising a filler C.

27. The polyamide composition according to claim 26, wherein the filler C is contained in an amount of 0.1 to 200 parts by mass based on 100 parts by mass of the polyamide a.

28. A polyamide composition according to any one of claims 22 to 27, further comprising a flame retardant aid D.

29. The polyamide composition according to claim 28, wherein the flame-retardant auxiliary D is contained in an amount of 1 to 30 parts by mass based on 100 parts by mass of the polyamide a.

30. The polyamide composition according to claim 28 or 29, wherein the flame retardant aid D is at least 1 selected from the group consisting of antimony trioxide, antimony tetraoxide, antimony pentoxide, sodium antimonate, melamine orthophosphate, melamine pyrophosphate, melamine borate, melamine polyphosphate, aluminum oxide, aluminum hydroxide, zinc borate and zinc stannate.

31. The polyamide composition according to claim 10, further comprising a halogen-free flame retardant B6.

32. The polyamide composition according to claim 31, wherein the halogen-free flame retardant B6 is contained in an amount of 5 to 100 parts by mass based on 100 parts by mass of the polyamide A.

33. The polyamide composition according to claim 31 or 32, wherein the halogen-free flame retardant B6 is at least 1 selected from the group consisting of a mono-phosphonate of the following general formula (1) and a di-phosphonate of the following general formula (2):

in the above general formulae (1) and (2), R¹、R²、R³And R⁴Each independently represents an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, R⁵Represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an alkylarylene group having 7 to 20 carbon atoms or an arylalkylene group having 7 to 20 carbon atoms, M represents calcium (ion), magnesium (ion), aluminum (ion) or zinc (ion), M is 2 or 3, n is 1 or 3, and x is 1 or 2.

34. A polyamide composition according to any one of claims 31 to 33 further comprising a filler C.

35. The polyamide composition according to claim 34, wherein the filler C is contained in an amount of 0.1 to 200 parts by mass based on 100 parts by mass of the polyamide a.

36. A molded article comprising the polyamide according to any one of claims 1 to 9.

37. A molded article formed from the polyamide composition as claimed in any one of claims 10 to 35.

38. The molded article according to claim 36 or 37, which is a film.

39. The molded article according to claim 36 or 37, which is an electric or electronic part.

40. The molded article according to claim 39, which is a surface-mount component.

Technical Field

The present invention relates to a polyamide, a polyamide composition, and the like. More specifically, the present invention relates to a semi-aromatic polyamide having a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of an aliphatic diamine unit, and a composition thereof.

Background

Crystalline polyamides such as semi-aromatic polyamides using an aromatic dicarboxylic acid such as terephthalic acid and an aliphatic diamine, nylon 6, nylon 66, and the like are widely used as fibers for clothing or industrial materials, general engineering plastics, and the like because of their excellent properties and ease of melt molding. On the other hand, these crystalline polyamides have been pointed out to have problems such as insufficient heat resistance and poor dimensional stability due to water absorption. In particular, in recent years, in order to improve the fuel consumption rate (number of kilometers of fuel per unit volume) of automobiles, intensive studies have been made on the resinification of engine room parts, and polyamides having excellent high-temperature strength, heat resistance, dimensional stability, mechanical properties, and physicochemical properties as compared with conventional polyamides have been desired.

As a polyamide having excellent heat resistance, for example, patent document 1 discloses a semi-aromatic polyamide obtained from 2, 6-naphthalenedicarboxylic acid and a linear aliphatic diamine having 9 to 13 carbon atoms. Patent document 1 describes that the semi-aromatic polyamide is excellent in chemical resistance, mechanical properties, and the like in addition to heat resistance. On the other hand, patent document 1 describes that the use of an aliphatic diamine having a side chain is not preferable because crystallinity of the obtained polyamide is lowered.

Patent document 2 discloses a polyamide in which 60 to 100 mol% of dicarboxylic acid units are composed of 2, 6-naphthalenedicarboxylic acid units, 60 to 100 mol% of diamine units are composed of 1, 9-nonanediamine units and 2-methyl-1, 8-octanediamine units, and the molar ratio of 1, 9-nonanediamine units to 2-methyl-1, 8-octanediamine units is 60/40 to 99/1. Patent document 2 describes that the polyamide is excellent in mechanical properties, thermal decomposition resistance, low water absorption, chemical resistance, and the like in addition to heat resistance.

Further, a resin composition containing a semi-aromatic polyamide, applications of a semi-aromatic polyamide, and the like are also disclosed (for example, patent documents 3 to 7).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 50-67393

Patent document 2: japanese laid-open patent publication No. 9-12715

Patent document 3: international publication No. 2012/098840

Patent document 4: international publication No. 2005/102681

Patent document 5: japanese laid-open patent publication No. 7-228771

Patent document 6: japanese patent laid-open publication No. 2006-152256

Patent document 7: japanese patent laid-open publication No. 2014-111761

Disclosure of Invention

Problems to be solved by the invention

As described above, although conventional polyamides such as patent documents 1 and 2 have physical properties such as heat resistance, mechanical properties, low water absorption, and chemical resistance, further improvement of these physical properties is required.

Patent document 2 describes the use of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine as the aliphatic diamine in combination, but does not mention polyamides in a region where the proportion of 2-methyl-1, 8-octanediamine having a side chain is high.

Accordingly, an object of the present invention is to provide a polyamide and a polyamide composition having more excellent various physical properties such as chemical resistance, and a molded article formed from the polyamide and the polyamide composition.

Means for solving the problems

The present inventors have conducted intensive studies and, as a result, have found that a specific polyamide having a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit can solve the above-mentioned problems, and have further conducted extensive studies based on the above knowledge, and have completed the present invention.

Namely, the present invention is as follows.

[1] A polyamide which is a polyamide (A) having a dicarboxylic acid unit and a diamine unit, wherein more than 40 mol% and 100 mol% or less of the dicarboxylic acid unit is a naphthalenedicarboxylic acid unit,

the diamine unit is a branched aliphatic diamine unit and a linear aliphatic diamine unit having an optional structural unit, and the proportion of the branched aliphatic diamine unit is 60 mol% or more based on 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.

[2] A polyamide composition comprising the above polyamide (A).

[3] The polyamide composition further contains a polyolefin (B1).

[4] The polyamide composition further contains an organic heat stabilizer (B2).

[5] The polyamide composition further contains a copper compound (B3) and a metal halogen compound (B4).

[6] The polyamide composition further contains a halogen-based flame retardant (B5).

[7] The polyamide composition further contains a halogen-free flame retardant (B6).

[8] A molded article comprising the polyamide (A) or the polyamide composition.

Effects of the invention

According to the present invention, a polyamide and a polyamide composition having more excellent various physical properties such as chemical resistance, and a molded article formed from the polyamide and the polyamide composition can be provided.

For example, a polyamide composition containing a polyamide (a) and a polyolefin (B1) is more excellent in impact resistance, heat resistance, chemical resistance, and the like.

Further, the polyamide composition containing the polyamide (a) and the organic heat stabilizer (B2) is more excellent in high-temperature heat resistance, chemical resistance, and the like.

Further, the polyamide composition containing the polyamide (a), the copper compound (B3) and the metal halogen compound (B4) is more excellent in high-temperature heat resistance, chemical resistance and the like.

The polyamide composition containing the polyamide (a) and the halogen flame retardant (B5) is further excellent in various physical properties and excellent in flame retardancy.

Further, the polyamide composition containing the polyamide (a) and the halogen-free flame retardant (B6) is more excellent in various physical properties, excellent in flame retardancy and less in environmental load.

Drawings

FIG. 1 is a graph obtained by plotting the melting point (. degree. C.) of a polyamide having a dicarboxylic acid unit of 2, 6-naphthalenedicarboxylic acid and a diamine unit of 1, 9-nonanediamine and/or 2-methyl-1, 8-octanediamine with respect to the content (mol%) of 2-methyl-1, 8-octanediamine units in the diamine unit.

Detailed Description

The present invention will be described in further detail below. In the present specification, the preferable specification can be arbitrarily adopted, and it is considered that the combinations of the preferable embodiments are more preferable. In the present specification, the expression "XX to YY" means "XX or more and YY or less".

< Polyamide (A) >

The polyamide (A) has a dicarboxylic acid unit and a diamine unit. The dicarboxylic acid unit in an amount of more than 40 mol% and 100 mol% or less is a naphthalenedicarboxylic acid unit. The diamine unit is a branched aliphatic diamine unit and a linear aliphatic diamine unit having an optional structural unit, and the proportion of the branched aliphatic diamine unit is 60 mol% or more based on 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit.

In the present specification, "unit" (here, "to" means a monomer) means a "structural unit derived from a unit", for example, "dicarboxylic acid unit" means a "structural unit derived from a dicarboxylic acid", and "diamine unit" means a "structural unit derived from a diamine".

The polyamide (a) has dicarboxylic acid units mainly composed of naphthalenedicarboxylic acid units and diamine units mainly composed of branched aliphatic diamine units as described above, and thus has more excellent physical properties such as chemical resistance. The composition containing the polyamide (a) also has the above-described excellent properties. In addition, various molded articles obtained from the polyamide (a) or the polyamide composition can maintain the excellent properties of the polyamide (a) or the polyamide composition.

Generally, the higher the crystallinity of polyamide, the more excellent the physical properties such as high-temperature strength, mechanical properties, heat resistance, low water absorption and chemical resistance which polyamide can have. In addition, between polyamides having similar primary structures, the melting point of the polyamide tends to increase as the crystallinity of the polyamide increases. Among them, the melting point of the polyamide is, for example, a polyamide in which the diamine unit is a1, 9-nonanediamine unit and/or a 2-methyl-1, 8-octanediamine unit, and the dicarboxylic acid unit is a terephthalic acid unit, and a very small portion is shown in a graph showing a relationship between the melting point (vertical axis) of the polyamide and the composition of the diamine unit (content ratio of the 1, 9-nonanediamine unit to the 2-methyl-1, 8-octanediamine unit) (horizontal axis). When the melting point at both ends on the abscissa of the graph, that is, the melting point a1 when the linear 1, 9-nonanediamine unit is 100 mol%, is compared with the melting point B1 when the branched 2-methyl-1, 8-octanediamine unit is 100 mol%, the melting point a1 is generally higher than the melting point B1 depending on the molecular structure of the diamine unit.

On the other hand, in the case of a polyamide having a diamine unit of 1, 9-nonanediamine unit and/or a 2-methyl-1, 8-octanediamine unit and a dicarboxylic acid unit of 2, 6-naphthalenedicarboxylic acid unit, the same graph having the vertical and horizontal axes as described above shows a very small portion, and on the other hand, when the melting point a2 at 100 mol% of the 1, 9-nonanediamine unit having a linear structure is compared with the melting point B2 at 100 mol% of the 2-methyl-1, 8-octanediamine unit having a branched structure, it is found that the melting point B2 is unexpectedly higher than the melting point a 2.

Specifically, FIG. 1 shows a graph in which the melting point (. degree. C.) of a polyamide having a dicarboxylic acid unit of 2, 6-naphthalenedicarboxylic acid and a diamine unit of 1, 9-nonanediamine and/or 2-methyl-1, 8-octanediamine is plotted against the content ratio (mol%) of 2-methyl-1, 8-octanediamine in the diamine unit.

As can be seen from fig. 1, the melting point of the polyamide was lowered as the content ratio of the 2-methyl-1, 8-octanediamine unit was increased with respect to the melting point of the polyamide having 0 mol% of the 2-methyl-1, 8-octanediamine unit (i.e., 100 mol% of the 1, 9-nonanediamine unit). On the other hand, it is found that the melting point of the polyamide is greatly increased as the content of the 2-methyl-1, 8-octanediamine unit is increased from the content of the 2-methyl-1, 8-octanediamine unit exceeding about 50 mol%. When the melting points near both ends on the horizontal axis of fig. 1 are compared, the melting point at the content ratio of 2-methyl-1, 8-octanediamine unit having a branched structure near 100 mol% is higher than the melting point at the content ratio of 1, 9-nonanediamine unit having a linear structure 100 mol%. In the region other than the vicinity of both ends on the horizontal axis, the melting point of the region around the region where the content of the 2-methyl-1, 8-octanediamine unit is higher than that of the region on the left side where the content of the 1, 9-nonanediamine unit is higher, with respect to the region around the region where the content of the 2-methyl-1, 8-octanediamine unit is higher than that of the region on the.

As described above, it is found that the polyamide having a diamine unit mainly composed of a1, 9-nonanediamine unit and/or a 2-methyl-1, 8-octanediamine unit has different physical properties depending on the dicarboxylic acid unit to be combined. The present inventors have further made studies and as a result, have found that when the content ratio of the branched aliphatic diamine unit is larger than that of the linear aliphatic diamine unit, various physical properties such as chemical resistance are further improved by using a naphthalenedicarboxylic acid unit as the dicarboxylic acid unit. The reason for this is not necessarily clear, but it is presumed that the presence of the naphthalene skeleton in the dicarboxylic acid unit correlates with the presence of the branched structure in the diamine unit in the polyamide.

(dicarboxylic acid unit)

More than 40 mol% and 100 mol% or less of the dicarboxylic acid units are naphthalenedicarboxylic acid units. When the content of the naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is 40 mol% or less, it becomes difficult to exhibit various effects of improving physical properties such as chemical resistance of the polyamide (a) and the polyamide composition.

The content of the naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is preferably 50 mol% or more, more preferably 60 mol% or more, even more preferably 70 mol% or more, even more preferably 80 mol% or more, even more preferably 90 mol% or more, and particularly preferably 100 mol%, from the viewpoints of mechanical properties, heat resistance, chemical resistance, and the like.

Examples of the naphthalenedicarboxylic acid unit include structural units derived from naphthalenedicarboxylic acids such as 1, 2-naphthalenedicarboxylic acid, 1, 3-naphthalenedicarboxylic acid, 1, 4-naphthalenedicarboxylic acid, 1, 5-naphthalenedicarboxylic acid, 1, 6-naphthalenedicarboxylic acid, 1, 7-naphthalenedicarboxylic acid, 1, 8-naphthalenedicarboxylic acid, 2, 3-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid and 2, 7-naphthalenedicarboxylic acid. These structural units may include only 1 kind, or may include 2 or more kinds. Among the naphthalenedicarboxylic acids, 2, 6-naphthalenedicarboxylic acid is preferred from the viewpoint of development of various physical properties such as chemical resistance and reactivity with diamines.

From the same viewpoint as above, the content of the structural unit derived from 2, 6-naphthalenedicarboxylic acid in the naphthalenedicarboxylic acid unit is preferably 90 mol% or more, more preferably 95 mol% or more, and preferably close to about 100 mol% (substantially 100 mol%).

The dicarboxylic acid unit may contain a structural unit derived from a dicarboxylic acid other than naphthalenedicarboxylic acid within a range not impairing the effects of the present invention.

Examples of the other dicarboxylic acid include aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecadicarboxylic acid, dodecanedicarboxylic acid, dimethylmalonic acid, 2-diethylsuccinic acid, 2-dimethylglutaric acid, 2-methyladipic acid, and trimethyladipic acid; alicyclic dicarboxylic acids such as 1, 3-cyclopentanedicarboxylic acid, 1, 3-cyclohexanedicarboxylic acid, 1, 4-cyclohexanedicarboxylic acid, cycloheptanedicarboxylic acid, cyclooctanedicarboxylic acid and cyclodecanedioic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2 '-biphenyldicarboxylic acid, 4' -biphenyldicarboxylic acid, diphenylmethane-4, 4 '-dicarboxylic acid, and diphenylsulfone-4, 4' -dicarboxylic acid. These structural units derived from other dicarboxylic acids may include only 1 type, or may include 2 or more types.

The content of the structural unit derived from another dicarboxylic acid in the dicarboxylic acid unit is preferably 50 mol% or less, more preferably 40 mol% or less, further preferably 30 mol% or less, further preferably 20 mol% or less, and further preferably 10 mol% or less.

(diamine unit)

60 to 100 mol% of the diamine units are branched aliphatic diamine units and optionally linear aliphatic diamine units. That is, the diamine unit contains a branched aliphatic diamine unit and does not contain a linear aliphatic diamine unit, or contains both a branched aliphatic diamine unit and a linear aliphatic diamine unit, and the total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit as an optional constituent unit in the diamine unit is 60 mol% or more and 100 mol% or less. When the total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit in the diamine unit is less than 60 mol%, it is difficult to exhibit various effects of improving physical properties such as chemical resistance of the polyamide (a) and the polyamide composition.

The total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit in the diamine unit is preferably 70 mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, and particularly preferably 100 mol%, from the viewpoints of chemical resistance, mechanical properties, heat resistance, and the like.

In the present specification, the branched aliphatic diamine means an aliphatic diamine having a structure in which, when a straight aliphatic chain having carbon atoms at both ends thereof to which 2 amino groups are bonded is assumed, 1 or more hydrogen atoms of the straight aliphatic chain (assumed to be an aliphatic chain) are substituted by a branch chain. I.e., for example, 1, 2-propanediamine (H)₂N-CH(CH₃)-CH₂-NH₂) The branched aliphatic diamine is classified in the present specification because it has a structure in which 1 hydrogen atom of a1, 2-ethylene group as an assumed aliphatic chain is substituted with a methyl group as a branch.

The proportion of the branched aliphatic diamine unit is 60 mol% or more based on 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit in the diamine unit. When the proportion of the branched aliphatic diamine unit is less than 60 mol%, it is difficult to exhibit various effects of improving physical properties such as chemical resistance of the polyamide (a) and the polyamide composition.

From the viewpoint of facilitating improvement of various physical properties such as chemical resistance and improvement of moldability of the polyamide (a) or the polyamide composition, the proportion of the branched aliphatic diamine unit is preferably 65 mol% or more, more preferably 70 mol% or more, further preferably 72 mol% or more, further preferably 77 mol% or more, further preferably 80 mol% or more, and may be 90 mol% or more, based on 100 mol% of the total of the branched aliphatic diamine unit and the linear aliphatic diamine unit. The proportion may be 100 mol%, but is preferably 99 mol% or less, may be 98 mol% or less, and may be 95 mol% or less, considering moldability, diamine availability, and the like.

The number of carbon atoms of the branched aliphatic diamine unit is preferably 4 or more, more preferably 6 or more, further preferably 8 or more, and further preferably 18 or less, more preferably 12 or less. When the number of carbon atoms of the branched aliphatic diamine unit is within the above range, the polymerization reaction between the dicarboxylic acid and the diamine proceeds well, the crystallinity of the polyamide (a) becomes good, and the physical properties of the polyamide (a) and the polyamide composition are easily further improved. As an example of a preferable embodiment of the number of carbon atoms of the branched aliphatic diamine unit, 4 to 18, 4 to 12, 6 to 18, 6 to 12, 8 to 18, and 8 to 12 may be mentioned.

The type of the branched chain in the branched aliphatic diamine unit is not particularly limited, and various aliphatic groups such as methyl group, ethyl group, and propyl group can be used, but the branched aliphatic diamine unit is preferably a structural unit derived from a diamine having at least 1 kind of branch selected from methyl group and ethyl group. When a diamine having at least 1 kind selected from methyl and ethyl as a branch is used, the polymerization reaction of the dicarboxylic acid and the diamine proceeds well, and the chemical resistance of the polyamide (a) and the polyamide composition is easily further improved. From this viewpoint, the branched chain is more preferably a methyl group.

The number of branches of the branched aliphatic diamine forming the branched aliphatic diamine unit is not particularly limited, and is preferably 3 or less, more preferably 2 or less, and still more preferably 1 from the viewpoint of more remarkably exerting the effect of the present invention.

The branched aliphatic diamine unit is preferably a unit derived from a diamine in which, when the carbon atom to which any one of the amino groups is bonded is the 1-position, at least one of the carbon atom at the 2-position adjacent thereto (the carbon atom in the assumed aliphatic chain) and the carbon atom at the 3-position adjacent to the carbon atom at the 2-position (the carbon atom in the assumed aliphatic chain) has at least 1 of branches, and more preferably at least 1 of branches. This makes it easy to further improve the chemical resistance of the polyamide (a) and the polyamide composition.

Examples of the branched aliphatic diamine unit include those derived from 1, 2-propanediamine, 1-butyl-1, 2-ethanediamine, 1-dimethyl-1, 4-butanediamine, 1-ethyl-1, 4-butanediamine, 1, 2-dimethyl-1, 4-butanediamine, 1, 3-dimethyl-1, 4-butanediamine, 1, 4-dimethyl-1, 4-butanediamine, 2-methyl-1, 3-propanediamine, 2-methyl-1, 4-butanediamine, 2, 3-dimethyl-1, 4-butanediamine, 2-methyl-1, 5-pentanediamine, 3-methyl-1, 5-pentanediamine, 2, 5-dimethyl-1, 6-hexamethylenediamine, 2, 4-dimethyl-1, 6-hexamethylenediamine, 3-dimethyl-1, 6-hexamethylenediamine, 2-dimethyl-1, 6-hexamethylenediamine, 2, 4-diethyl-1, 6-hexamethylenediamine, 2, 4-trimethyl-1, 6-hexamethylenediamine, 2, 4, 4-trimethyl-1, 6-hexamethylenediamine, 2-ethyl-1, 7-heptanediamine, 2-methyl-1, 8-octanediamine, 3-methyl-1, 8-octanediamine, 1, 3-dimethyl-1, 8-octanediamine, 1, 4-dimethyl-1, 8-octanediamine, 2, 4-dimethyl-1, a structural unit of a branched aliphatic diamine unit such as 8-octanediamine, 3, 4-dimethyl-1, 8-octanediamine, 4, 5-dimethyl-1, 8-octanediamine, 2-dimethyl-1, 8-octanediamine, 3-dimethyl-1, 8-octanediamine, 4-dimethyl-1, 8-octanediamine, 2-methyl-1, 9-nonanediamine, or 5-methyl-1, 9-nonanediamine. These structural units may include only 1 kind, or may include 2 or more kinds.

Among the branched aliphatic diamine units, from the viewpoint of more remarkably exerting the effects of the present invention and also excellent in raw material availability, a structural unit derived from at least 1 diamine selected from the group consisting of 2-methyl-1, 5-pentanediamine, 3-methyl-1, 5-pentanediamine, 2-methyl-1, 8-octanediamine and 2-methyl-1, 9-nonanediamine is preferable, and a structural unit derived from 2-methyl-1, 8-octanediamine is more preferable.

The number of carbon atoms of the linear aliphatic diamine unit is preferably 4 or more, more preferably 6 or more, further preferably 8 or more, and further preferably 18 or less, more preferably 12 or less. When the number of carbon atoms of the linear aliphatic diamine unit is within the above range, the polymerization reaction between the dicarboxylic acid and the diamine proceeds well, the crystallinity of the polyamide (a) becomes good, and the physical properties of the polyamide (a) and the polyamide composition are easily improved. As an example of a preferable embodiment of the number of carbon atoms of the linear aliphatic diamine unit, 4 or more and 18 or less, 4 or more and 12 or less, 6 or more and 18 or less, 6 or more and 12 or less, 8 or more and 18 or less, or 8 or more and 12 or less may be used.

The number of carbons of the linear aliphatic diamine unit and the branched aliphatic diamine unit may be the same or different, but the same is preferable from the viewpoint of more remarkably exhibiting the effect of the present invention.

Examples of the linear aliphatic diamine unit include structural units derived from linear aliphatic diamines such as ethylenediamine, 1, 3-propanediamine, 1, 4-butanediamine, 1, 5-pentanediamine, 1, 6-hexanediamine, 1, 7-heptanediamine, 1, 8-octanediamine, 1, 9-nonanediamine, 1, 10-decanediamine, 1, 11-undecanediamine, 1, 12-dodecanediamine, 1, 13-tridecanediamine, 1, 14-tetradecanediamine, 1, 15-pentadecanediamine, 1, 16-hexadecanediamine, 1, 17-heptadecanediamine, and 1, 18-octadecanediamine. These structural units may include only 1 kind, or may include 2 or more kinds.

Among the above linear aliphatic diamine units, from the viewpoint of more remarkably exerting the effects of the present invention, particularly, from the viewpoint of improving the heat resistance of the polyamide (a) and the polyamide composition to be obtained, it is preferable to use a structural unit derived from at least 1 kind of diamine selected from 1, 4-butanediamine, 1, 5-pentanediamine, 1, 6-hexanediamine, 1, 7-heptanediamine, 1, 8-octanediamine, 1, 9-nonanediamine, 1, 10-decanediamine, 1, 11-undecanediamine, and 1, 12-dodecanediamine, and more preferable to use a structural unit derived from 1, 9-nonanediamine.

The diamine unit may contain a structural unit derived from a diamine other than the branched diamine and the linear diamine within a range not to impair the effects of the present invention. Examples of the other diamine include alicyclic diamines and aromatic diamines.

Examples of the alicyclic diamine include cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, norbornanediamine, tricyclodecanedimethyldiamine, and the like.

Examples of the aromatic diamine include p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 4 ' -diaminodiphenylmethane, 4 ' -diaminodiphenylsulfone, and 4, 4 ' -diaminodiphenylether.

These structural units derived from other diamines may include only 1 kind, or may include 2 or more kinds.

The content of the structural unit derived from the other diamine in the diamine unit is preferably 30 mol% or less, more preferably 20 mol% or less, and further preferably 10 mol% or less.

(dicarboxylic acid units and diamine units)

The molar ratio of the dicarboxylic acid unit to the diamine unit [ dicarboxylic acid unit/diamine unit ] in the polyamide (A) is preferably 45/55 to 55/45. When the molar ratio of the dicarboxylic acid unit to the diamine unit is in the above range, the polymerization reaction proceeds well, and the desired polyamide (a) and polyamide composition having excellent physical properties can be easily obtained.

The molar ratio of the dicarboxylic acid unit to the diamine unit can be adjusted according to the mixing ratio (molar ratio) of the dicarboxylic acid of the raw material and the diamine of the raw material.

The total ratio of the dicarboxylic acid unit and the diamine unit in the polyamide (a) (the ratio of the total number of moles of the dicarboxylic acid unit and the diamine unit to the number of moles of the total structural units constituting the polyamide (a)) is preferably 70 mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, and may be 95 mol% or more, and may be 100 mol%. When the total ratio of the dicarboxylic acid unit and the diamine unit is within the above range, the polyamide (a) and the polyamide composition having more excellent desired physical properties can be obtained.

(aminocarboxylic acid unit)

The polyamide (a) may further contain an aminocarboxylic acid unit in addition to the dicarboxylic acid unit and the diamine unit.

Examples of the aminocarboxylic acid unit include lactams such as caprolactam and laurolactam; and structural units derived from aminocarboxylic acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid. The content of the aminocarboxylic acid unit in the polyamide (a) is preferably 40 mol% or less, and more preferably 20 mol% or less, based on 100 mol% of the total of the dicarboxylic acid unit and the diamine unit constituting the polyamide (a).

(polycarboxylic acid unit)

The polyamide (a) may contain a structural unit derived from a 3-or more-membered polycarboxylic acid such as trimellitic acid, trimesic acid, or pyromellitic acid in a range that does not impair the effects of the present invention.

(capping agent Unit)

The polyamide (a) may contain a structural unit derived from an end-capping agent (end-capping agent unit).

The capping agent unit is preferably 1.0 mol% or more, more preferably 1.2 mol% or more, further preferably 1.5 mol% or more, and further preferably 10 mol% or less, more preferably 7.5 mol% or less, and further preferably 6.5 mol% or less, based on 100 mol% of the diamine unit. When the content of the end-capping agent unit is in the above range, the polyamide (a) and the polyamide composition having more excellent mechanical strength and flowability are obtained. The content of the end-capping agent unit can be set within the above-mentioned desired range by appropriately adjusting the amount of the end-capping agent at the time of charging the polymerization raw material. In consideration of volatilization of the monomer component during polymerization, it is desirable to finely adjust the amount of the end-capping agent to introduce a desired amount of end-capping agent units into the polyamide (a) obtained.

Examples of the method for determining the content of the terminal-blocking agent unit in the polyamide (a) include: a method in which the viscosity of the solution is measured, the total amount of terminal groups is calculated from a relational expression between the viscosity and the number average molecular weight, and the amount of amino groups and the amount of carboxyl groups determined by titration are subtracted therefrom, as shown in Japanese patent laid-open No. 7-228690; use of¹H-NMR is a method of obtaining an integral value of a signal corresponding to each of the diamine unit and the capping agent unit, and the latter is preferable.

As the end-capping agent, a monofunctional compound having reactivity with a terminal amino group or a terminal carboxyl group can be used. Specific examples thereof include monocarboxylic acids, acid anhydrides, monoisocyanates, monoacyl halides, monoesters, monoalcohols, and monoamines. From the viewpoints of reactivity, stability of blocked ends, and the like, monocarboxylic acids are preferred as the blocking agents corresponding to the terminal amino groups, and monoamines are preferred as the blocking agents corresponding to the terminal carboxyl groups. From the viewpoint of ease of handling and the like, monocarboxylic acid is more preferable as the end-capping agent.

The monocarboxylic acid used as the end-capping agent is not particularly limited as long as it has reactivity with an amino group, and examples thereof include aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid; alicyclic monocarboxylic acids such as cyclopentanecarboxylic acid and cyclohexanecarboxylic acid; aromatic monocarboxylic acids such as benzoic acid, methylbenzoic acid, α -naphthoic acid, β -naphthoic acid, methylnaphthoic acid, and phenylacetic acid; mixtures of any of these, and the like. Among them, from the viewpoints of reactivity, stability of a blocked terminal, price, and the like, at least 1 selected from the group consisting of acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, and benzoic acid is preferable.

The monoamine used as the blocking agent is not particularly limited as long as it has reactivity with the carboxyl group, and examples thereof include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, and the like; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine; mixtures of any of these, and the like. Among them, at least 1 selected from the group consisting of butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline is preferable from the viewpoints of reactivity, high boiling point, stability of blocked terminal, price, and the like.

The polyamide (A) has an intrinsic viscosity [. eta. ] measured at a concentration of 0.2g/dl and a temperature of 30 ℃ using concentrated sulfuric acid as a solvent_inh]Preferably 0.1dl/g or more, more preferably 0.4dl/g or more, further preferably 0.6dl/g or more, particularly preferably 0.8dl/g or more, and further preferably 3.0dl/g or less, more preferably 2.0dl/g or less, further preferably 1.8dl/g or less. If the intrinsic viscosity [ eta ] of the polyamide (A)_inh]When the content is within the above range, various physical properties such as moldability are further improved. Intrinsic viscosity [ eta ]_inh]Can be determined according to the flowing-down time t of the solvent (concentrated sulfuric acid)₀(second) time t of sample solution flowing down₁(seconds) and samplesSample concentration c (g/dl) (i.e., 0.2g/dl) in solution, passing eta_inh＝[ln(t₁/t₀)]The relation of/c is obtained.

The melting point of the polyamide (a) is not particularly limited, and may be, for example, 260 ℃ or higher, 270 ℃ or higher, or 280 ℃ or higher, but from the viewpoint of more remarkably exhibiting the effects of the present invention, the melting point is preferably 290 ℃ or higher, more preferably 295 ℃ or higher, further preferably 300 ℃ or higher, further preferably 305 ℃ or higher, further preferably 310 ℃ or higher, and may be 315 ℃ or higher. The upper limit of the melting point of the polyamide (A) is not particularly limited, but considering moldability and the like, it is preferably 330 ℃ or lower, more preferably 320 ℃ or lower, and still more preferably 317 ℃ or lower. The melting point of the polyamide (a) can be determined as the peak temperature of a melting peak occurring when the temperature is raised at a rate of 10 ℃/min using a Differential Scanning Calorimetry (DSC) apparatus, and more specifically can be determined by the method described in examples.

The glass transition temperature of the polyamide (a) is not particularly limited, and may be, for example, 100 ℃ or higher, 110 ℃ or higher, or 120 ℃ or higher, but from the viewpoint of more remarkably exhibiting the effect of the present invention, it is preferably 125 ℃ or higher, more preferably 130 ℃ or higher, still more preferably 135 ℃ or higher, still more preferably 137 ℃ or higher, still more preferably 138 ℃ or higher, or 139 ℃ or higher. The upper limit of the glass transition temperature of the polyamide (A) is not particularly limited, but considering moldability and the like, it is preferably 180 ℃ or lower, more preferably 160 ℃ or lower, and further preferably 150 ℃ or lower. The glass transition temperature of the polyamide (a) can be determined as the temperature of the inflection point appearing when the temperature is raised at a rate of 20 ℃/min using a Differential Scanning Calorimetry (DSC) apparatus, and more specifically can be determined by the method described in examples.

(Process for producing Polyamide (A))

The polyamide (a) can be produced by any method known as a method for producing a crystalline polyamide, and can be produced by, for example, a melt polymerization method, a solid phase polymerization method, a melt extrusion polymerization method, or the like using a dicarboxylic acid and a diamine as raw materials. Among them, the method for producing the polyamide (a) is preferably a solid-phase polymerization method from the viewpoint that thermal deterioration during polymerization can be more favorably suppressed.

In order to set the molar ratio of the branched aliphatic diamine unit to the linear aliphatic diamine unit within the above-mentioned specific numerical range, the branched aliphatic diamine and the linear aliphatic diamine used as raw materials may be used in such a blending ratio that the molar ratio of the units is required.

When 2-methyl-1, 8-octanediamine and 1, 9-nonanediamine are used as the branched aliphatic diamine and the linear aliphatic diamine, respectively, they can be produced by a known method. Examples of the known method include a method of distilling a crude diamine reaction solution obtained by reductive amination using dialdehyde as a starting material. Further, 2-methyl-1, 8-octanediamine and 1, 9-nonanediamine can be obtained by fractionating the crude reaction solution of the diamines.

The polyamide (a) can be produced, for example, by the following method: first, a nylon salt is produced by adding a diamine, a dicarboxylic acid, and if necessary, a catalyst and a capping agent together, and then the mixture is heated and polymerized at a temperature of 200 to 250 ℃ to produce a prepolymer, which is further subjected to solid-phase polymerization or polymerization using a melt extruder. In the case of carrying out the final stage of polymerization by solid-phase polymerization, it is preferable to carry out the polymerization under reduced pressure or under inert gas flow, and if the polymerization temperature is in the range of 200 to 280 ℃, the polymerization rate is high, the productivity is excellent, and coloring and gelation can be effectively suppressed. The polymerization temperature in the final stage of the polymerization by the melt extruder is preferably 370 ℃ or lower, and the polyamide (a) hardly decomposes and is hardly deteriorated when polymerized under such conditions.

Examples of the catalyst that can be used in the production of the polyamide (a) include phosphoric acid, phosphorous acid, hypophosphorous acid, and salts and esters thereof. Examples of the salts or esters include salts of phosphoric acid, phosphorous acid, or hypophosphorous acid with metals such as potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, and antimony; ammonium salts of phosphoric acid, phosphorous acid or hypophosphorous acid; ethyl, isopropyl, butyl, hexyl, isodecyl, octadecyl, decyl, stearyl, phenyl, etc., of phosphoric acid, phosphorous acid, or hypophosphorous acid.

The amount of the catalyst to be used is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and further preferably 1.0% by mass or less, more preferably 0.5% by mass or less, based on 100% by mass of the total mass of the raw materials of the polyamide (a). If the amount of the catalyst used is not less than the lower limit, the polymerization proceeds well. If the content is less than the upper limit, impurities derived from the catalyst are less likely to be generated, and for example, when the polyamide (a) or the polyamide composition containing the same is formed into a film, problems due to the impurities can be prevented.

< Polyamide composition >

The present invention also provides a polyamide composition comprising the above polyamide (A).

Examples of the other components other than the polyamide (a) contained in the polyamide composition include inorganic fillers, organic fillers, crystal nucleating agents, antioxidants, colorants, antistatic agents, plasticizers, slip agents, dispersants, flame retardants, flame retardant aids, and the like. They may contain only 1 species or 2 or more species.

The content of the other components in the polyamide composition is not particularly limited, and may be appropriately adjusted depending on the kind of the other components, the use of the polyamide composition, and the like, and may be, for example, 80% by mass or less, 50% by mass or less, 30% by mass or less, 15% by mass or less, 5% by mass or less, 1% by mass or less, and the like, based on the mass of the polyamide composition.

The polyamide composition contains the polyamide (a), and thus has more excellent chemical resistance. The polyamide composition of the present invention is preferably 5% or less, more preferably 3% or less, further preferably 2.8% or less, and may be 2.6% or less, 2.5% or less, and may be 2.4% or less, based on the weight of the test piece before immersion, after injection molding into a test piece having a thickness of 4mm, and immersion thereof in an antifreeze solution (an aqueous solution obtained by diluting "ultra-long life coolant" (pink) manufactured by toyota corporation, by 2 times) at 130 ℃ for 500 hours. More specifically, the weight gain can be determined by the method described in examples.

The retention of tensile break strength after immersion in an antifreeze solution (an aqueous solution obtained by diluting "ultra-long life coolant" (pink) manufactured by toyota car corporation) at 130 ℃ for 500 hours after injection molding the above polyamide composition into a test piece having a thickness of 4mm is preferably 50% or more, more preferably 80% or more, and may be 90% or more, 95% or more, and may be 98% or more, based on the tensile break strength before immersion. The retention of the tensile break strength can be determined more specifically by the method described in examples.

The polyamide composition contains the polyamide (a) and thus has more excellent mechanical properties. The tensile breaking strength at 23 ℃ of the polyamide composition when injection-molded into a test piece having a thickness of 4mm is preferably 70MPa or more, more preferably 80MPa or more, further preferably 90MPa or more, and may be 100MPa or more. The flexural strength at 23 ℃ of the polyamide composition when injection-molded into a test piece having a thickness of 4mm is preferably 110MPa or more, more preferably 120MPa or more, still more preferably 125MPa or more, and may be 130MPa or more. These tensile breaking strength and bending strength can be determined by the methods described in examples.

The polyamide composition contains the polyamide (a), and thus has more excellent heat resistance. The heat distortion temperature of the polyamide composition when injection-molded into a test piece having a thickness of 4mm is preferably 120 ℃ or more, more preferably 130 ℃ or more, further preferably 140 ℃ or more, further preferably 145 ℃ or more, particularly preferably 148 ℃ or more, and may be 150 ℃ or more. The heat distortion temperature can be specifically determined by the method described in examples.

The polyamide composition contains the polyamide (a), and thus has excellent low water absorption. The polyamide composition is preferably 0.5% or less, more preferably 0.3% or less, further preferably 0.28% or less, and may be 0.27% or less, and may be 0.26% or less, based on the weight of the test piece before immersion, after injection molding into a test piece having a thickness of 4mm and immersion in water at 23 ℃ for 168 hours. The water absorption can be more specifically determined by the method described in examples.

The polyamide composition preferably has a storage modulus at 23 ℃ after forming a film having a thickness of 200 μm of 2.5GPa or more, more preferably 3.0GPa or more, and may have a storage modulus of 3.2GPa or more, 3.4GPa or more, and may have a storage modulus of 3.5GPa or more. The storage modulus at 150 ℃ of the polyamide composition after the production of a film having a thickness of 200 μm is preferably 0.5GPa or more, more preferably 1.0GPa or more, still more preferably 1.2GPa or more, particularly preferably 1.5GPa or more, and may be 1.7GPa or more, 1.8GPa or more, 1.9GPa or more, and may be 2.0GPa or more. The α relaxation temperature (peak temperature of loss tangent) of the polyamide composition after the composition is formed into a film having a thickness of 200 μm is preferably 140 ℃ or more, and more preferably 150 ℃ or more. These storage modulus and α relaxation temperature can be specifically determined by the methods described in examples.

In addition, according to the embodiment of the present invention in which the polyamide composition contains the polyamide (a) and the specific component, a polyamide composition having further excellent physical properties according to the specific component can be produced. Specifically, preferred embodiments are described below, but the present invention is not limited to these embodiments.

< embodiment 1 >

The polyamide composition of embodiment 1 contains a polyamide (a) and a polyolefin (B1).

As described above, the polyamide (a) has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus has excellent various physical properties such as chemical resistance, and a polyamide composition containing the polyamide (a) and the polyolefin (B1) also exhibits excellent impact resistance and heat resistance while retaining the above excellent properties. In addition, various molded articles obtained from the polyamide composition can maintain the excellent properties of the polyamide composition.

[ polyolefin (B1) ]

The polyamide composition of embodiment 1 contains a polyolefin (B1). By containing the polyolefin (B1), a polyamide composition having excellent impact resistance, heat resistance and chemical resistance is obtained.

The polyolefin (B1) is not particularly limited as long as the effects of the present invention can be obtained, and is preferably at least 1 selected from the following (B1-1) to (B1-5).

(b1-1) alpha-olefin copolymer

(b1-2) copolymer of at least 1 member selected from the group consisting of ethylene, propylene and α -olefin having 4 or more carbon atoms and at least 1 member selected from the group consisting of α, β -unsaturated carboxylic acid, α, β -unsaturated carboxylic acid ester and α, β -unsaturated carboxylic acid anhydride

(b1-3) the ionomer of (b1-2)

(b1-4) copolymer of aromatic vinyl Compound and conjugated diene Compound

(b1-5) A Polymer obtained by modifying at least 1 selected from the group consisting of the above (b1-1) to (b1-4) with an unsaturated Compound having at least 1 selected from the group consisting of a carboxyl group and an acid anhydride group

(b1-1) alpha-olefin copolymer

Examples of the α -olefin copolymer include a copolymer of ethylene and an α -olefin having 3 or more carbon atoms, and a copolymer of propylene and an α -olefin having 4 or more carbon atoms.

Examples of the α -olefin having 3 or more carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-hexene, 4-dimethyl-1-hexene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 4, 4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and the like. These alpha-olefins may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

Further, (b1-1) the α -olefin copolymer may be 1, 4-pentadiene, 1, 4-hexadiene, 1, 5-hexadiene, 1, 4-octadiene, 1, 5-octadiene, 1, 6-octadiene, 1, 7-octadiene, 2-methyl-1, 5-hexadiene, 6-methyl-1, 5-heptadiene, 7-methyl-1, 6-octadiene, 4-ethylidene-8-methyl-1, 7-nonadiene, 4, 8-dimethyl-1, 4, 8-decatriene (DMDT), dicyclopentadiene, cyclohexadiene, cyclooctadiene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 1, 4-dimethyl-1, 8-decatriene (DMDT), 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, 2, 3-diisopropyl-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2, 5-norbornadiene and other unconjugated polyenes. These non-conjugated polyenes may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

(b1-2) copolymer

(b1-2) the copolymer is a copolymer of at least 1 member selected from the group consisting of ethylene, propylene and α -olefin having 4 or more carbon atoms and at least 1 member selected from the group consisting of α, β -unsaturated carboxylic acid, α, β -unsaturated carboxylic acid ester and α, β -unsaturated carboxylic acid anhydride.

The α -olefin may be an α -olefin having 4 or more carbon atoms in the α -olefin described in the description of the (b1-1) α -olefin copolymer. These α -olefins having 4 or more carbon atoms may be used alone in 1 kind or in combination with 2 or more kinds.

Examples of the α, β -unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, and the like, and 1 kind or 2 or more kinds of these α, β -unsaturated carboxylic acids may be used alone.

Examples of the α, β -unsaturated carboxylic acid ester include methyl ester, ethyl ester, propyl ester, butyl ester, pentyl ester, hexyl ester, heptyl ester, octyl ester, nonyl ester, decyl ester, and the like of the above α, β -unsaturated carboxylic acid, and these α, β -unsaturated carboxylic acid esters may be used alone in 1 kind, or 2 or more kinds may be used in combination.

Examples of the α, β -unsaturated carboxylic acid anhydride include maleic anhydride and itaconic anhydride, and 1 kind or 2 or more kinds of these α, β -unsaturated carboxylic acid anhydrides may be used alone or in combination.

The at least one selected from the group consisting of an α, β -unsaturated carboxylic acid, an α, β -unsaturated carboxylic acid ester and an α, β -unsaturated carboxylic acid anhydride is preferably an α, β -unsaturated carboxylic acid anhydride, and more preferably maleic anhydride.

Ionomer (b1-3)

The ionomer (b1-3) includes a copolymer (b1-2) in which at least a part of the carboxyl groups is ionized by neutralization with a metal ion. Examples of the metal ion include alkali metals and alkaline earth metals such as Li, Na, K, Mg, Ca, Sr and Ba, and also include Al, Sn, Sb, Ti, Mn, Fe, Ni, Cu, Zn and Cd. These metal ions may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

(b1-4) copolymer

The copolymer (b1-4) is a copolymer of an aromatic vinyl compound and a conjugated diene compound, and is preferably a block copolymer. Examples of the block copolymer include a block copolymer (aromatic vinyl compound/conjugated diene compound block copolymer) comprising an aromatic vinyl compound polymer block and a conjugated diene compound polymer block, and preferably a block copolymer having at least 1 aromatic vinyl compound polymer block and at least 1 conjugated diene compound polymer block. In the block copolymer, a part or all of the unsaturated bonds in the conjugated diene compound polymer block may be hydrogenated.

The aromatic vinyl compound polymer block is a polymer block mainly composed of a structural unit derived from an aromatic vinyl compound. Examples of the aromatic vinyl compound include styrene, α -methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2, 4-dimethylstyrene, vinylnaphthalene, vinylanthracene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, and 4- (phenylbutyl) styrene, and 1 kind of the aromatic vinyl compound may be used alone or 2 or more kinds may be used in combination.

In addition, the aromatic vinyl compound polymer block may have a small amount of a structural unit derived from another unsaturated monomer, as the case may be.

The conjugated diene compound polymer block is a polymer block mainly composed of a structural unit derived from a conjugated diene compound. Examples of the conjugated diene compound include 1, 3-butadiene, chloroprene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, 4-methyl-1, 3-pentadiene, 1, 3-hexadiene and the like, and 1 kind thereof may be used alone or 2 or more kinds may be used in combination.

In the hydrogenated aromatic vinyl compound/conjugated diene compound block copolymer, typically, a part or all of the unsaturated bond portion in the conjugated diene compound polymer block is hydrogenated to a single bond.

The molecular structure of the aromatic vinyl compound/conjugated diene compound block copolymer (which may be a hydrogenated product) may be any of linear, branched, radial, and any combination thereof. Among them, as the aromatic vinyl compound/conjugated diene compound block copolymer (may be a hydrogenated product), preferably used is 1 or 2 or more of a diblock copolymer in which 1 aromatic vinyl compound polymer block and 1 conjugated diene compound polymer block are linearly bonded, and a triblock copolymer (may be a hydrogenated product) in which 3 polymer blocks are linearly bonded in the order of aromatic vinyl compound polymer block-conjugated diene compound polymer block-aromatic vinyl compound polymer block.

Examples of the aromatic vinyl compound/conjugated diene compound block copolymer (which may be hydrogenated) include an unhydrogenated or hydrogenated styrene/butadiene block copolymer, an unhydrogenated or hydrogenated styrene/isoprene/styrene block copolymer, an unhydrogenated or hydrogenated styrene/butadiene/styrene block copolymer, and an unhydrogenated or hydrogenated styrene/(isoprene and butadiene)/styrene block copolymer.

(b1-5) modified Polymer

(b1-5) the modified polymer is a polymer obtained by modifying at least 1 selected from the group consisting of (b1-1) to (b1-4) above with an unsaturated compound having at least 1 selected from the group consisting of a carboxyl group and an acid anhydride group.

Examples of the unsaturated compound having a carboxyl group include α, β -unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid. Examples of the unsaturated compound having an acid anhydride group include dicarboxylic anhydrides having an α, β -unsaturated bond such as maleic anhydride and itaconic anhydride. The unsaturated compound having at least 1 selected from the group consisting of a carboxyl group and an acid anhydride group is preferably a dicarboxylic anhydride having an α, β -unsaturated bond, and more preferably maleic anhydride.

The total content of the carboxyl group and the acid anhydride group in the modified polymer (b1-5) is preferably in the range of 25 to 200. mu. mol/g, more preferably in the range of 50 to 100. mu. mol/g. If the content is 25. mu. mol/g or more, the effect of improving mechanical properties is sufficient, while if it is 200. mu. mol/g or less, the moldability of the polyamide composition is improved.

Examples of the modification method using an unsaturated compound include a method of copolymerizing an unsaturated compound in producing at least one selected from the group consisting of (b1-1) to (b1-4) (hereinafter, also referred to as "base resin") by addition polymerization, and a method of graft-reacting the unsaturated compound with a base resin, and the latter is preferable.

The polyolefin (B1) may be used alone in 1 kind or in combination of 2 or more kinds. From the viewpoint of obtaining the effects of the present invention, the polyolefin (B1) is preferably a (B1-5) modified polymer, more preferably a polymer obtained by modifying an α -olefin copolymer with an unsaturated compound having at least 1 selected from a carboxyl group and an acid anhydride group, and still more preferably a maleic anhydride modified product of an ethylene-propylene copolymer.

When the modified polymer (B1-5) is used as the polyolefin (B1), the terminal amino group of the polyamide (A) reacts with the carboxyl group and/or acid anhydride group of the modified polymer (B1-5), whereby the affinity of the interface between the (A) phase and the (B) phase is enhanced, and the mechanical properties such as impact resistance and elongation properties are further improved.

As the modified polymer (b1-5), a commercially available product such as "TAFMER (registered trademark)" manufactured by Mitsui chemical Co., Ltd. can be used.

The polyamide composition according to embodiment 1 preferably contains the polyolefin (B1) in an amount of 1 to 100 parts by mass based on 100 parts by mass of the polyamide (a). The content of the polyolefin (B1) is more preferably 2 parts by mass or more, and still more preferably 3 parts by mass or more, per 100 parts by mass of the polyamide (a). The content of the polyolefin (B1) is more preferably 80 parts by mass or less, still more preferably 65 parts by mass or less, and still more preferably 50 parts by mass or less with respect to 100 parts by mass of the polyamide (a), and may be 30 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less. When the content of the polyolefin (B1) is 1 part by mass or more, the polyamide composition tends to exhibit impact resistance and heat resistance, and molded articles obtained by molding the polyamide composition are less likely to suffer from defects such as cracking. Further, if the content of the polyolefin (B1) is 100 parts by mass or less, a polyamide composition having more excellent impact resistance, heat resistance and chemical resistance can be obtained.

The total content of the polyamide (a) and the polyolefin (B1) in the polyamide composition according to embodiment 1 is preferably 85 mass% or more, more preferably 90 mass% or more, further preferably 92 mass% or more, and may be 95 mass% or more and 97 mass% or more. The total content of the polyamide (a) and the polyolefin (B1) in the polyamide composition according to embodiment 1 may be 100 mass%, but is preferably less than 100 mass% in consideration of the amount of other additives described later added as needed, and may be 99.5 mass% or less and 99 mass% or less.

When the total content of the polyamide (a) and the polyolefin (B1) in the polyamide composition of embodiment 1 is within the above range, the polyamide composition is likely to exhibit excellent physical properties such as impact resistance, heat resistance, and chemical resistance.

[ optional Components ]

The polyamide composition of embodiment 1 may contain, in addition to the above-mentioned polyamide (A) and polyolefin (B1), an organic heat stabilizer (B2) (e.g., a phenol-based heat stabilizer, a phosphorus-based heat stabilizer, a sulfur-based heat stabilizer, and an amine-based heat stabilizer), a copper compound (B3), a metal halide (B4), a halogen-based flame retardant (B5) (e.g., a brominated polymer), a halogen-free flame retardant (B6), a filler (C) (e.g., an inorganic or organic fibrous filler such as a glass fiber, a carbon fiber, and a wholly aromatic polyamide fiber), a powdery filler such as wollastonite, silica alumina, titanium dioxide, potassium titanate, magnesium hydroxide, molybdenum disulfide, a carbon nanotube, graphene, polytetrafluoroethylene, and ultrahigh-molecular-weight polyethylene, a hydrotalcite, a glass flake, a mica, and a filler, A sheet filler such as clay, montmorillonite or kaolin), and a flame retardant aid (D). These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The content of each of these components (B2), (B3), (B4), (B5), (B6), (C) and (D) in the polyamide composition of embodiment 1 is not particularly limited as long as the effects of the present invention are not impaired, and preferred ranges are as described below.

(other additives)

Further, the polyamide composition of embodiment 1 may contain other additives as needed.

Examples of the other additives include colorants such as carbon black; an ultraviolet absorber; a light stabilizer; an antistatic agent; a crystal nucleating agent; a plasticizer; a lubricant; a slip agent; a dispersant; an oxygen absorbent; a hydrogen sulfide adsorbent; impact modifiers such as rubbers (excluding polyolefin (B1)). These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The content of the other additives is not particularly limited as long as the effect of the present invention is not impaired.

As a preferred embodiment of the polyamide composition according to embodiment 1, the total content of the components (B2), (B3), (B4), (B5), (B6), (C) and (D) and the other additives is preferably 0.02 to 200 parts by mass, more preferably 0.03 to 100 parts by mass, based on 100 parts by mass of the polyamide (a).

The polyamide composition according to embodiment 1 is preferably 5% or less, more preferably 4% or less, and still more preferably 3.5% or less, based on the weight of the test piece before immersion, after injection molding into a test piece having a thickness of 4mm, and immersion in an antifreeze solution (an aqueous solution obtained by diluting "ultra-long life coolant" (pink) manufactured by toyota corporation) at 130 ℃ for 500 hours. More specifically, the weight gain can be determined by the method described in examples.

The retention of the tensile break strength of the polyamide composition of embodiment 1 after injection molding into a test piece having a thickness of 4mm and immersion in an antifreeze (an aqueous solution obtained by diluting "ultra-long life coolant" (pink) manufactured by toyota corporation) at 130 ℃ for 500 hours is preferably 60% or more, more preferably 70% or more, and still more preferably 73% or more, based on the tensile break strength before immersion. The retention of the tensile break strength can be determined more specifically by the method described in examples.

In the polyamide composition of embodiment 1, when a test piece having a thickness of 4mm is cut into a notched test piece after injection molding, the Charpy impact value at room temperature is preferably 5kJ/m²Above, more preferably 6kJ/m²Above, more preferably 7kJ/m²The above. Furthermore, the Charpy impact value at-40 ℃ is preferably 3kJ/m²More preferably 4kJ/m²More preferably 4.5kJ/m². More specifically, the impact value can be determined by the method described in examples.

The heat distortion temperature of the polyamide composition of embodiment 1 when injection-molded into a test piece having a thickness of 4mm is preferably 130 ℃ or more, more preferably 140 ℃ or more, and still more preferably 144 ℃ or more. The heat distortion temperature can be specifically determined by the method described in examples.

The tensile breaking strength of the polyamide composition of embodiment 1 when injection-molded into a test piece having a thickness of 4mm is preferably 50MPa or more, more preferably 55MPa or more, and may be 90MPa or more. The tensile strain at break of the polyamide composition of embodiment 1 when injection molded into a test piece having a thickness of 4mm is preferably 10% or more, more preferably 14% or more, and may be 20% or more. The tensile strength at break and the tensile strain at break can be specifically determined by the methods described in examples.

The polyamide composition of embodiment 1 is preferably 0.5% or less, more preferably 0.4% or less, and even more preferably 0.3% or less, based on the weight of the test piece before immersion, after injection molding into a test piece having a thickness of 4mm and immersion in water at 23 ℃ for 168 hours. The water absorption can be more specifically determined by the method described in examples.

< embodiment 2 >

The polyamide composition according to embodiment 2 contains a polyamide (a) and an organic heat stabilizer (B2).

The content of the polyamide (a) in the polyamide composition of embodiment 2 is preferably 50% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, further preferably 80% by mass or more, further preferably 90% by mass or more, and particularly preferably 95% by mass or more, from the viewpoint of chemical resistance, and is preferably 99.9% by mass or less, and more preferably 99.8% by mass or less from the viewpoint of mechanical properties, heat resistance, and the like.

As described above, the polyamide (a) has dicarboxylic acid units mainly composed of naphthalenedicarboxylic acid units and diamine units mainly composed of branched aliphatic diamine units, and thus is more excellent in various physical properties such as chemical resistance, and the polyamide composition of embodiment 2 containing the polyamide (a) and the organic heat stabilizer (B2) also exhibits excellent high-temperature heat resistance while retaining the above excellent properties. In addition, various molded articles obtained from the polyamide composition can maintain the excellent properties of the polyamide composition.

[ organic Heat stabilizer (B2) ]

As the organic heat stabilizer (B2) contained in the polyamide composition of embodiment 2, known compounds can be used, but at least 1 selected from the group consisting of a phenol heat stabilizer (B2-1), a phosphorus heat stabilizer (B2-2), a sulfur heat stabilizer (B2-3) and an amine heat stabilizer (B2-4) is preferable.

Phenol type heat stabilizer (B2-1)

Examples of the phenolic heat stabilizer (B2-1) include hindered phenol compounds. The hindered phenol compound has a property of imparting heat resistance and light resistance to a resin such as polyamide.

Examples of the hindered phenol compound include 2, 2-thio-diethylene bis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ], N '-hexane-1, 6-diylbis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionamide ], pentaerythritol-tetrakis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ], N' -hexamethylenebis (3, 5-di-t-butyl-4-hydroxyphenyl) propionamide, triethyleneglycol bis (3-t-butyl-4-hydroxy-5-methylphenyl) propionate, hexamethylenebis (3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate), 3, 9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] -1, 1-dimethylethyl } -2, 4, 8, 10-tetraoxaspiro [5.5] undecane, tris (3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, diethyl 3, 5-di-tert-butyl-4-hydroxybenzylphosphonate, 1, 3, 5-trimethyl-2, 4, 6-tris (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene, 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) isocyanuric acid, and the like.

The phenolic heat stabilizer (B2-1) may be used alone in 1 kind or in combination with 2 or more kinds. Particularly, from the viewpoint of improving heat resistance, 3, 9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] -1, 1-dimethylethyl } -2, 4, 8, 10-tetraoxaspiro [5.5] undecane is preferable.

When the phenolic heat stabilizer (B2-1) is used, the content thereof is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1 part by mass, based on 100 parts by mass of the polyamide (A). In the case of being within the above range, the heat resistance can be further improved.

Phosphorus Heat stabilizer (B2-2)

Examples of the phosphorus-based heat stabilizer (B2-2) include monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, magnesium phosphite, manganese phosphite, pentaerythritol-type phosphite compounds, trioctyl phosphite, trilauryl phosphite, octyldiphenyl phosphite, triisodecyl phosphite, phenyldiisodecyl phosphite, phenylditridecyl phosphite, diphenylisooctyl phosphite, diphenylisodecyl phosphite, diphenyl (tridecyl) phosphite, triphenyl phosphite, trioctadecyl phosphite, tridecyl phosphite, tris (nonylphenyl) phosphite, tris (2, 4-di-t-butylphenyl) phosphite, tris (2, 4-di-t-butyl-5-methylphenyl) phosphite, tris (butoxyethyl) phosphite, tri (octylphenyl) phosphite, and mixtures thereof, 4, 4 ' -butylidene-bis (3-methyl-6-tert-butylphenyl-tetrakis (tridecyl)) diphosphite, tetrakis (C12-C15 mixed alkyl) -4, 4 ' -isopropylidene diphenyl diphosphite, 4 ' -isopropylidene bis (2-tert-butylphenyl) -bis (nonylphenyl) phosphite, tris (biphenyl) phosphite, tetrakis (tridecyl) -1, 1, 3-tris (2-methyl-5-tert-butyl-4-hydroxyphenyl) butane diphosphite, tetrakis (tridecyl) -4, 4 ' -butylidene bis (3-methyl-6-tert-butylphenyl) diphosphite, tetrakis (C1-C15 mixed alkyl) -4, 4 ' -isopropylidene diphenyl diphosphite, and mixtures thereof, Tris (mono-and di-mixed nonylphenyl) phosphite, 4 ' -isopropylidenebis (2-tert-butylphenyl) bis (nonylphenyl) phosphite, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, tris (3, 5-di-tert-butyl-4-hydroxyphenyl) phosphite, hydrogenated-4, 4 ' -isopropylidenediphenyl phosphite, bis (octylphenyl) bis (4, 4 ' -butylidenebis (3-methyl-6-tert-butylphenyl)). 1, 6-hexanol diphosphite, hexakistridecyl-1, 1, 3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) diphosphite, tris (4, 4 ' -isopropylidenebis (2-tert-butylphenyl)) phosphite, tris (1, 3-stearoyloxyisopropyl) phosphite, 2-methylenebis (4, 6-di-tert-butylphenyl) octyl phosphite, 2-methylenebis (3-methyl-4, 6-di-tert-butylphenyl) -2-ethylhexyl phosphite, tetrakis (2, 4-di-tert-butyl-5-methylphenyl) -4, 4 ' -biphenyl diphosphite, tetrakis (2, 4-di-tert-butylphenyl) -4, 4 ' -biphenyl diphosphite, 6- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propoxy ] -2, 4, 8, 10-tetra-tert-butylbenzo [ d, f ] [1, 3, 2] -dioxaphosphocycloheptadiene and the like.

The phosphorus-based heat stabilizer (B2-2) may be used alone in 1 kind or in combination with 2 or more kinds. The phosphorus-based heat stabilizer (B2-2) is preferably a pentaerythritol-type phosphite compound or tris (2, 4-di-t-butylphenyl) phosphite in view of further improving heat resistance.

Examples of the pentaerythritol-type phosphite compound include 2, 6-di-t-butyl-4-methylphenyl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl methyl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl 2-ethylhexyl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl isodecyl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl lauryl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl isotridecyl pentaerythritol diphosphite, 2, 6-di-t-butyl-4-methylphenyl stearyl pentaerythritol diphosphite, 2, 2, 6-di-tert-butyl-4-methylphenylcyclohexyl pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenylbenzyl pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenylethylcellulose pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenylcarbinol pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenyloctylphenyl pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenylnonylphenyl pentaerythritol diphosphite, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2, 6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenyl 2, 6-di-tert-butylphenyl pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenyl 2, 4-di-tert-octylphenyl pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenyl 2-cyclohexylphenyl pentaerythritol diphosphite, 2, 6-di-tert-pentyl-4-methylphenyl pentaerythritol diphosphite, bis (2, 4-dicumylphenyl) pentaerythritol diphosphite, 2, 6-di-tert-butyl-4-methylphenyl pentaerythritol diphosphite, 2, 4-dicumylphenyl, Bis (2, 6-di-t-amyl-4-methylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-octyl-4-methylphenyl) pentaerythritol diphosphite, and the like. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Among them, bis (2, 4-dicumylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-pentyl-4-methylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-octyl-4-methylphenyl) pentaerythritol diphosphite, and more preferably bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite are preferable.

When the phosphorus-based heat stabilizer (B2-2) is used, the content thereof is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1 part by mass, based on 100 parts by mass of the polyamide (A). When the amount is within the above range, the heat resistance can be further improved.

Sulfur-based Heat stabilizer (B2-3)

Examples of the sulfur-based heat stabilizer (B2-3) include distearyl 3, 3 ' -thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), 2-mercaptobenzimidazole, didodecyl 3, 3 ' -thiodipropionate, ditridecyl 3, 4 ' -thiodipropionate, and 2, 2-bis [ [3- (dodecylthio) -1-oxopropoxy ] methyl ] -1, 3-propanediyl ester.

The sulfur-based heat stabilizer (B2-3) may be used alone in 1 kind or in combination with 2 or more kinds.

When the sulfur-based heat stabilizer (B2-3) is used, the content thereof is preferably 0.02 to 4 parts by mass, more preferably 0.2 to 2 parts by mass, based on 100 parts by mass of the polyamide (A). When the amount is within the above range, the heat resistance can be further improved.

Amine Heat stabilizer (B2-4)

Examples of the amine-based heat stabilizer "B2-4" include 4, 4 ' -bis (. alpha.,. alpha. -dimethylbenzyl) diphenylamine ("Nocrac CD" manufactured by Dainihiji Kagaku Kogyo Co., Ltd.), N ' -di-2-naphthyl-p-phenylenediamine ("Nocrac White" manufactured by Dainihiji Kagaku Kogyo Co., Ltd.), N ' -diphenyl-p-phenylenediamine ("Nocrac DP" manufactured by Dainihiji Kagaku Kogyo Co., Ltd.), N-phenyl-1-naphthylamine ("Nocrac PA" manufactured by Dainihiji Kagaku Kogyo Co., Ltd.), N-phenyl-N ' -isopropyl-p-phenylenediamine ("Nocrac 810-NA" manufactured by Dainihiji Kagaku Kogyo Co., Ltd.), and N-phenyl-N ' - (1, 3-dimethylbutyl) -p-phenylenediamine ("Nocrac PA" manufactured by Dainihiji Kagaku Kogyo Co., Ltd 6C ', etc.), N-phenyl-N' - (3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine (Nocrac G-1, etc., available from Dai Neigheng chemical industries Co., Ltd.), 4-acetoxy-2, 2, 6, 6-tetramethylpiperidine, 4-stearoyloxy-2, 2, 6, 6-tetramethylpiperidine, 4-acryloyloxy-2, 2, 6, 6-tetramethylpiperidine, 4- (phenylacetyloxy) -2, 2, 6, 6-tetramethylpiperidine, 4-benzoyloxy-2, 2, 6, 6-tetramethylpiperidine, 4-methoxy-2, 2, 6, 6-tetramethylpiperidine, 4-stearoyloxy-2, 2, 6, 6-tetramethylpiperidine, 4-cyclohexyloxy-2, 2, 6, 6-tetramethylpiperidine, 4-benzyloxy-2, 2, 6, 6-tetramethylpiperidine, 4-phenoxy-2, 2, 6, 6-tetramethylpiperidine, 4- (ethylcarbamoyloxy) -2, 2, 6, 6-tetramethylpiperidine, 4- (cyclohexylcarbamoyloxy) -2, 2, 6, 6-tetramethylpiperidine, 4- (phenylcarbamoyloxy) -2, 2, 6, 6-tetramethylpiperidine, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) carbonate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) oxalate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl)) malonate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) sebacate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) adipate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) terephthalate, 1, 2-bis (2, 2, 6, 6-tetramethyl-4-piperidyloxy) ethane, α' -bis (2, 2, 6, 6-tetramethyl-4-piperidyloxy) -p-xylene, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) tolylene-2, 4-dicarbamate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) hexamethylene-1, 6-dicarbamate, tris (2, 2, 6, 6-tetramethyl-4-piperidyl) benzene-1, 3, 5-tricarboxylate, tris (2, 2, 6, 6-tetramethyl-4-piperidyl) benzene-1, 3, 4-tricarboxylate, 1- [2- {3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyloxy } butyl ] -4- [3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyloxy ]2, 2, 6, 6-tetramethylpiperidine, 1, 2, 3, 4-butanetetracarboxylic acid with 1, 2, 2, 6, 6-pentamethyl-4-piperidinol with β, β, β ', β' -tetramethyl-3, and condensates of 9- [2, 4, 8, 10-tetraoxaspiro [5.5] undecane ] diethanol.

The amine heat stabilizer (B2-4) may be used alone in 1 kind or in combination of 2 or more kinds.

When the amine-based heat stabilizer (B2-4) is used, the content thereof is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1 part by mass, based on 100 parts by mass of the polyamide (A). When the amount is within the above range, the heat resistance can be further improved.

The polyamide composition according to embodiment 2 preferably contains the organic heat stabilizer (B2) in an amount of 0.05 to 5 parts by mass based on 100 parts by mass of the polyamide (a). The content of the organic heat stabilizer (B2) is more preferably 0.1 part by mass or more, still more preferably 3 parts by mass or less, and may be 2 parts by mass or less and 1 part by mass or less with respect to 100 parts by mass of the polyamide (a).

When the content of the organic heat stabilizer (B2) is within the above range, the heat resistance of the polyamide composition can be further improved. When a plurality of organic heat stabilizers (B2) are used, the total amount thereof may fall within the above range.

The total content of the polyamide (a) and the organic heat stabilizer (B2) in the polyamide composition according to embodiment 2 is preferably 50% by mass or more, more preferably 55% by mass or more, further preferably 60% by mass or more, and may be 90% by mass or more and 95% by mass or more. The total content of the polyamide (a) and the organic heat stabilizer (B2) in the polyamide composition according to embodiment 2 may be 100 mass%, but is preferably less than 100 mass% in consideration of the amount of other additives to be added as needed, which will be described later, and may be 99.5 mass% or less and 99 mass% or less.

When the total content of the polyamide (a) and the organic heat stabilizer (B2) in the polyamide composition according to embodiment 2 is within the above range, excellent physical properties such as high-temperature heat resistance and chemical resistance of the polyamide composition are easily exhibited.

[ optional Components ]

The polyamide composition of embodiment 2 may contain, in addition to the polyamide (a) and the organic heat stabilizer (B2), the above-described polyolefin (B1), a copper compound (B3) described later, a metal halide (B4), a halogen-based flame retardant (B5) (e.g., a brominated polymer), a halogen-free flame retardant (B6), a filler (C) (e.g., an inorganic or organic fibrous filler such as a glass fiber, a carbon fiber, or a wholly aromatic polyamide fiber, a powdery filler such as wollastonite, silica alumina, titanium dioxide, potassium titanate, magnesium hydroxide, molybdenum disulfide, a carbon nanotube, graphene, polytetrafluoroethylene, or ultrahigh molecular weight polyethylene, a sheet-like filler such as hydrotalcite, a glass sheet, mica, clay, montmorillonite, or kaolin), and a flame retardant aid (D), as required. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The content of each of these components (B1), (B3), (B4), (B5), (B6), (C) and (D) in the polyamide composition of embodiment 2 is not particularly limited as long as the effect of the present invention is not impaired, and preferable ranges are as described above or below.

(other additives)

Further, the polyamide composition of embodiment 2 may contain other additives as needed. Examples of the other additives include those similar to the "other additives" in the description of the polyamide composition of embodiment 1.

The content of the other additives is not particularly limited as long as the effect of the present invention is not impaired.

As a preferred embodiment of the polyamide composition of embodiment 2, the total content of the components (B1), (B3), (B4), (B5), (B6), (C) and (D) and the other additives is preferably 0.02 to 200 parts by mass, more preferably 0.03 to 100 parts by mass, based on 100 parts by mass of the polyamide (a).

The tensile breaking strength at 23 ℃ of the polyamide composition of embodiment 2 when injection-molded into a test piece having a thickness of 4mm is preferably 70MPa or more, more preferably 80MPa or more, further preferably 90MPa or more, and may be 100MPa or more. The tensile break strength can be determined by the method described in examples.

The heat distortion temperature of the polyamide composition of embodiment 2 when injection-molded into a test piece having a thickness of 4mm is preferably 130 ℃ or more, more preferably 140 ℃ or more, further preferably 145 ℃ or more, and may be 150 ℃ or more. The heat distortion temperature can be specifically determined by the method described in examples.

The polyamide composition of embodiment 2 is preferably 0.4% or less, more preferably 0.3% or less, further preferably 0.28% or less, and may be 0.27% or less, and may be 0.26% or less, based on the weight of the test piece before immersion, after injection molding into a test piece having a thickness of 4mm, and after immersion in water at 23 ℃ for 168 hours. The water absorption can be more specifically determined by the method described in examples.

The retention of the tensile break strength of the polyamide composition of embodiment 2 after injection molding into a test piece having a thickness of 4mm and immersion at 130 ℃ for 500 hours in an antifreeze (an aqueous solution obtained by diluting "ultra-long life coolant" (pink) manufactured by toyota corporation) is preferably 50% or more, more preferably 80% or more, and may be 90% or more, 95% or more, and further 98% or more, based on the tensile break strength before immersion. The retention of the tensile break strength can be determined more specifically by the method described in examples.

The retention of the tensile break strength of the polyamide composition of embodiment 2 after injection molding into a test piece having a thickness of 2mm and leaving it to stand in a dryer at 120 ℃ for 500 hours is preferably 80% or more, more preferably 90% or more, and may be 95% or more, 98% or more, and may be 100% based on the tensile break strength before leaving. The retention of the tensile break strength can be determined more specifically by the method described in examples.

< embodiment 3 >

The polyamide composition according to embodiment 3 contains a polyamide (a), a copper compound (B3), and a metal halogen compound (B4).

As described above, the polyamide (a) has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus is more excellent in various physical properties such as chemical resistance, and the polyamide composition of embodiment 3 containing the polyamide (a), the copper compound (B3) and the metal halide (B4) also exhibits excellent high-temperature heat resistance while retaining the excellent properties described above. In addition, various molded articles obtained from the polyamide composition can maintain the excellent properties of the polyamide composition.

[ copper Compound (B3) and Metal halide (B4) ]

The polyamide composition according to embodiment 3 contains the copper compound (B3) and the metal halide (B4), and thus can obtain a polyamide composition having further high-temperature heat resistance, specifically, excellent heat aging resistance and heat resistance at a high temperature of 150 ℃. Hereinafter, the copper compound (B3) and the metal halide (B4) will be further described.

Copper compound (B3)

Examples of the copper compound (B3) include copper halide, copper acetate, copper propionate, copper benzoate, copper adipate, copper terephthalate, copper isophthalate, copper salicylate, copper nicotinate, copper stearate, and copper complex salts obtained by coordinating with a chelating agent such as ethylenediamine or ethylenediamine tetraacetic acid. Examples of the copper halide include copper iodide; copper bromides such as cuprous bromide and cupric bromide; copper chloride such as cuprous chloride, and the like. Among these copper compounds, from the viewpoint of excellent heat aging resistance and being capable of suppressing corrosion of metals in a screw and a barrel portion during extrusion, at least 1 selected from copper halide and copper acetate is preferable, at least 1 selected from copper iodide, copper bromide, copper chloride and copper acetate is more preferable, and at least 1 selected from copper iodide, copper bromide and copper acetate is further preferable. The copper compound (B3) may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The content of the copper compound (B3) in the polyamide composition according to embodiment 3 is preferably 0.01 to 1 part by mass, more preferably 0.02 to 0.5 part by mass, and still more preferably 0.06 to 0.4 part by mass, based on 100 parts by mass of the polyamide (a). When the content of the copper compound (B3) is in the above range, the resulting polyamide composition can be improved in high-temperature heat resistance such as heat aging resistance while suppressing a decrease in tensile physical properties, and can be suppressed in copper deposition and metal corrosion during molding.

Metal halide (B4)

As the metal halide (B4), a metal halide other than the copper compound (B3) can be used, and a salt of a metal element of group 1 or group 2 of the periodic table and a halogen is preferable. Examples thereof include potassium iodide, potassium bromide, potassium chloride, sodium iodide, and sodium chloride. Among them, from the viewpoint of excellent high-temperature heat resistance such as heat aging resistance and the like of the obtained polyamide composition and the ability to suppress metal corrosion, at least 1 selected from potassium iodide and potassium bromide is preferable, and potassium iodide is more preferable. The metal halide (B4) may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The content of the metal halide (B4) in the polyamide composition according to embodiment 3 is preferably 0.05 parts by mass or more and 20 parts by mass or less, more preferably 0.2 parts by mass or more and 10 parts by mass or less, and still more preferably 0.5 parts by mass or more and 9 parts by mass or less, with respect to 100 parts by mass of the polyamide (a). When the content of the metal halide (B4) is in the above range, the resulting polyamide composition can be improved in high-temperature heat resistance such as heat aging resistance while suppressing a decrease in tensile properties, and can be suppressed in copper deposition and metal corrosion during molding.

Regarding the ratio of the copper compound (B3) to the metal halide (B4) in the polyamide composition of embodiment 3, it is preferable that the polyamide composition contains the copper compound (B3) and the metal halide (B4) such that the ratio of the total molar amount of halogen to the total molar amount of copper (halogen/copper) is 2/1 to 50/1. The above ratio (halogen/copper) is preferably 3/1 or more, more preferably 4/1 or more, further preferably 5/1 or more, and further preferably 45/1 or less, more preferably 40/1 or less, further preferably 30/1 or less. When the ratio (halogen/copper) is not less than the lower limit, copper deposition and metal corrosion during molding can be more effectively suppressed. When the ratio (halogen/copper) is not more than the above upper limit, corrosion of a screw of a molding machine and the like can be more effectively suppressed without impairing mechanical properties such as tensile properties of the obtained polyamide composition.

From the viewpoint of excellent high-temperature heat resistance such as heat aging resistance of the obtained polyamide composition, the copper compound (B3) and the metal halide (B4) are used in combination. The total content of the copper compound (B3) and the metal halide (B4) is preferably 0.06 parts by mass or more, more preferably 0.1 parts by mass or more, further preferably 0.3 parts by mass or more, and further preferably 0.5 parts by mass or more, based on 100 parts by mass of the polyamide (a). The total content of the copper compound (B3) and the metal halide (B4) is preferably 21 parts by mass or less, more preferably 10 parts by mass or less, further preferably 5 parts by mass or less, and may be 3 parts by mass or less and 2 parts by mass or less, based on 100 parts by mass of the polyamide (a).

When the total content of the copper compound (B3) and the metal halide (B4) is in the above range, the problems such as metal corrosion of the polyamide composition can be more effectively suppressed, and the high-temperature heat resistance such as heat aging resistance can be improved.

The total content of the polyamide (a), the copper compound (B3), and the metal halide (B4) in the polyamide composition according to embodiment 3 is more preferably 90% by mass or more, still more preferably 92% by mass or more, and may be 95% by mass or more and 97% by mass or more. The total content of the polyamide (a), the copper compound (B3), and the metal halide (B4) in the polyamide composition according to embodiment 3 may be 100 mass%, but is preferably less than 100 mass% in consideration of the amount of other additives to be added as needed, which will be described later, and may be 99.5 mass% or less and 99 mass% or less.

If the total content of the polyamide (a), the copper compound (B3), and the metal halide (B4) in the polyamide composition according to embodiment 3 is within the above range, the polyamide composition is likely to exhibit excellent physical properties such as high-temperature heat resistance and chemical resistance.

[ optional Components ]

The polyamide composition of embodiment 3 may contain, in addition to the above-mentioned polyamide (A), copper compound (B3) and metal halide (B4), the above-mentioned polyolefin (B1) and organic heat stabilizer (B2) (e.g., phenol heat stabilizer, phosphorus heat stabilizer, sulfur heat stabilizer, amine heat stabilizer), halogen flame retardant (B5) (e.g., brominated polymer) described later, halogen flame retardant (B6), filler (C) (e.g., inorganic or organic fibrous filler such as glass fiber, carbon fiber, wholly aromatic polyamide fiber, wollastonite, silica alumina, titanium dioxide, potassium titanate, magnesium hydroxide, molybdenum disulfide, carbon nanotube, graphene, polytetrafluoroethylene, ultrahigh-molecular-weight polyethylene, hydrotalcite, glass flake, metal halide, Sheet fillers such as mica, clay, montmorillonite and kaolin), and a flame retardant aid (D). These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The content of each of these components (B1), (B2), (B5), (B6), (C) and (D) in the polyamide composition according to embodiment 3 is not particularly limited as long as the effect of the present invention is not impaired, and preferable ranges are as described above or below.

(other additives)

Further, the polyamide composition of embodiment 3 may contain other additives as needed. Examples of the other additives include those similar to the "other additives" in the description of the polyamide composition of embodiment 1.

The content of the other additives is not particularly limited as long as the effect of the present invention is not impaired.

In particular, as the dispersant used as another additive, a dispersant capable of dispersing the copper compound (B3) and the metal halide (B4) in the polyamide (a) can be preferably used. Examples of the dispersant include higher fatty acids such as lauric acid; higher fatty acid metal salts formed from higher fatty acids and metals such as aluminum; higher fatty acid amides such as ethylene bis stearamide; waxes such as polyethylene wax; organic compounds having at least one amide group, and the like.

As a preferred embodiment of the polyamide composition of embodiment 3, the total content of the components (B1), (B2), (B5), (B6), (C) and (D) and the other additives is preferably 0.02 to 200 parts by mass, more preferably 0.03 to 100 parts by mass, based on 100 parts by mass of the polyamide (a).

< embodiment 4 >

The polyamide composition according to embodiment 4 contains a polyamide (a) and a halogen-based flame retardant (B5).

As described above, the polyamide (a) has dicarboxylic acid units mainly composed of naphthalenedicarboxylic acid units and diamine units mainly composed of branched aliphatic diamine units, and thus has more excellent physical properties such as chemical resistance, and the polyamide composition of embodiment 4 containing the polyamide (a) and the halogen-based flame retardant (B5) also retains the above excellent properties and has excellent flame retardancy. In addition, various molded articles obtained from the polyamide composition can maintain the excellent properties of the polyamide composition.

[ halogen-based flame retardant (B5) ]

The halogen-based flame retardant (B5) contained in the polyamide composition according to embodiment 4 is not particularly limited, and a compound known as a flame retardant containing a halogen element can be used. Examples of the halogen-based flame retardant (B5) include a bromine-based flame retardant (B5-1) and a chlorine-based flame retardant (B5-2), and a bromine-based flame retardant (B5-1) is preferable. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

(brominated flame retardant (B5-1))

Examples of the bromine-based flame retardant include hexabromocyclododecane, decabromodiphenyl oxide, octabromodiphenyl oxide, tetrabromobisphenol A, bis (tribromophenoxy) ethane, bis (pentabromophenoxy) ethane, tetrabromobisphenol A epoxy resin, tetrabromobisphenol A carbonate, ethylene (bistetrabromophthalimide), ethylenebistentabromodiphenyl, tris (tribromophenoxy) triazine, bis (dibromopropyl) tetrabromobisphenol A, bis (dibromopropyl) tetrabromobisphenol S, brominated polyphenylene ethers (including poly (di) bromophenylene ether) and the like), brominated polystyrenes (including polydibromostyrene, polytribromostyrene, crosslinked brominated polystyrenes and the like, and may be modified brominated polystyrenes to which an epoxy acrylate or the like is added), brominated crosslinked aromatic polymers, brominated epoxy resins, brominated phenoxy resins, brominated styrene-maleic anhydride polymers, and the like, Tetrabromobisphenol S, tris (tribromoneopentyl) phosphate, polybromotrimethylphenylindane, tris (dibromopropyl) -isocyanurate, and the like.

The brominated flame retardant (B5-1) is preferably a brominated polyphenylene ether or a brominated polystyrene, more preferably a brominated polystyrene, from the viewpoints of reducing the amount of corrosive gas generated during melt processing such as extrusion and molding and improving the flame retardancy and mechanical properties of electrical and electronic parts.

The brominated polystyrene can be produced, for example, by a method of preparing polystyrene by polymerizing a styrene monomer, and then brominating the benzene ring of the polystyrene, or a method of polymerizing a brominated styrene monomer (bromostyrene, dibromostyrene, tribromostyrene, or the like).

The bromine content in the brominated polystyrene is preferably 55 to 75 mass%. By setting the bromine content to 55 mass% or more, the amount of bromine required for flame retardancy can be satisfied with a small content of brominated polystyrene, and a decrease in mechanical properties of the polyamide (a) can be suppressed, whereby a polyamide composition having excellent mechanical properties and heat resistance can be obtained. Further, by setting the bromine content to 75% by mass or less, a polyamide composition which is less likely to cause thermal decomposition during melt processing such as extrusion and molding, can suppress gas generation, and has excellent thermal discoloration resistance can be obtained.

(chlorine series flame retardant (B5-2))

Examples of the chlorine-based flame retardant include chlorinated paraffin, chlorinated polyethylene, dodecachloropentacyclooctadeca-7, 15-diene ("Dechlorane Plus 25" manufactured by Occidental Chemical Co., Ltd.), and chlorendic anhydride.

(content of halogen-based flame retardant, etc.)

The polyamide composition according to embodiment 4 preferably contains the halogen flame retardant (B5) in an amount of 5 parts by mass or more and 100 parts by mass or less based on 100 parts by mass of the polyamide (a). The content of the halogen-based flame retardant (B5) is more preferably 10 parts by mass or more, and still more preferably 30 parts by mass or more, per 100 parts by mass of the polyamide (a). The content of the halogen-based flame retardant (B5) is more preferably 75 parts by mass or less, still more preferably 70 parts by mass or less, and may be 60 parts by mass or less, based on 100 parts by mass of the polyamide (a).

By setting the content of the halogen-based flame retardant (B5) to 5 parts by mass or more, a polyamide composition having excellent flame retardancy can be obtained. Further, by setting the content of the halogen-based flame retardant (B5) to 100 parts by mass or less, generation of decomposition gas during melt kneading, reduction in fluidity (particularly thin-wall fluidity) during molding, adhesion of contaminants to a molding die, and reduction in mechanical properties and appearance of a molded article can be suppressed. When a plurality of halogen flame retardants (B5) are used, the total amount thereof may fall within the above range.

The total content of the polyamide (a) and the halogen-based flame retardant (B5) in the polyamide composition according to embodiment 4 is more preferably 50% by mass or more, and still more preferably 55% by mass or more. The total content of the polyamide (a) and the halogen-based flame retardant (B5) in the polyamide composition according to embodiment 4 may be 100 mass%, but is preferably less than 100 mass% in consideration of the amounts of the filler (C), the flame retardant aid (D), and other additives, which will be described later, added as needed, and may be 90 mass% or less, 80 mass% or less, and 70 mass% or less.

According to the studies of the present inventors, it was found that, with respect to a polyamide constituting a polyamide composition, when more than 40 mol% of dicarboxylic acid units constituting the polyamide are naphthalenedicarboxylic acid units, flame retardancy tends to be further improved by the combination of a halogen-based flame retardant and the polyamide as compared with a case where more than 40 mol% of dicarboxylic acid units constituting the polyamide are terephthalic acid units. It has also been found that this tendency is exhibited irrespective of the ratio of the linear aliphatic diamine unit to the branched aliphatic diamine unit in the diamine units constituting the polyamide. Therefore, for example, assuming an application in which only the importance of specific physical properties of the semi-aromatic polyamide is required, when a polyamide composition is produced using a polyamide in which the ratio of the branched aliphatic diamine units to the diamine units is larger than the ratio of the linear aliphatic diamine units and a halogen-based flame retardant, there is a possibility that a polyamide composition having both the above-described specific physical properties and flame retardancy can be formed.

[ Filler (C) ]

The polyamide composition of embodiment 4 may contain a filler (C). By using the filler (C), a polyamide composition excellent in flame retardancy, heat resistance, moldability and mechanical strength in a thin-walled state can be obtained.

As the filler (C), fillers having various forms such as a fiber form, a flat plate form, a needle form, a powder form, and a cloth form can be used. Specific examples thereof include inorganic or organic fibrous fillers (C1) such as glass fibers, carbon fibers, wholly aromatic polyamide fibers (aramid fibers), Liquid Crystal Polymer (LCP) fibers, gypsum fibers, brass fibers, ceramic fibers, and boron whisker fibers; flat fillers such as glass flakes, mica, and talc; acicular fillers (C2) such as potassium titanate whiskers, aluminum borate whiskers, calcium carbonate whiskers, magnesium sulfate whiskers, wollastonite, sepiolite, xonotlite, zinc oxide whiskers; powdery fillers such as silica, silica alumina, barium carbonate, magnesium carbonate, aluminum nitride, boron nitride, potassium titanate, titanium oxide, magnesium hydroxide, aluminum silicate (kaolin, clay, pyrophyllite, bentonite), calcium silicate, magnesium silicate (attapulgite), aluminum borate, calcium sulfate, barium sulfate, magnesium sulfate, asbestos, glass beads, carbon black, graphene, graphite, carbon nanotubes, silicon carbide, sericite, hydrotalcite, montmorillonite, molybdenum disulfide, ultra-high molecular weight polyethylene particles, phenol resin particles, crosslinked styrene resin particles, crosslinked acrylic resin particles, and the like; cloth-like fillers such as glass cloth. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The surface of the filler (C) may be surface-treated with a high molecular compound such as a silane coupling agent, a titanium coupling agent, an acrylic resin, a urethane resin, and an epoxy resin, or another low molecular compound in order to improve dispersibility and adhesiveness in the polyamide (a).

Among the fillers (C), at least 1 selected from fibrous fillers (C1) and acicular fillers (C2) is preferable in view of low cost and obtaining a molded article having high mechanical strength. From the viewpoint of high strength and low cost, the fibrous filler (C1) is preferable, and glass fiber or carbon fiber is more preferable. The needle-like filler (C2) is preferred from the viewpoint of obtaining a molded article having high surface smoothness.

The fibrous filler (C1) and the acicular filler (C2) are preferably at least 1 selected from glass fibers, carbon fibers, wollastonite, potassium titanate whiskers, calcium carbonate whiskers, and aluminum borate whiskers, more preferably at least 1 selected from glass fibers, carbon fibers, and wollastonite, and still more preferably at least 1 selected from glass fibers and carbon fibers.

The average fiber length of the fibrous filler (C1) is usually about 0.1 to 10mm, but from the viewpoint of high-temperature strength, heat resistance and mechanical strength of the polyamide composition, it is preferably 0.5 to 6mm, more preferably 1 to 6 mm. The average fiber diameter of the fibrous filler (C1) is usually about 0.5 to 250 μm, but is preferably 3 to 100 μm, more preferably 3 to 30 μm, from the viewpoint of a good contact area with the polyamide (A) and mechanical strength of the molded article.

The average fiber length and the average fiber diameter of the fibrous filler (C1) were determined by measuring the fiber length and the fiber diameter of each of 400 randomly selected fibrous fillers (C1) and calculating the mass average value of each of the 400 fibrous fillers by image analysis using an electron microscope.

The average fiber length and average fiber diameter of the fibrous filler (C1) in the polyamide composition or in the molded article obtained by molding the polyamide composition can be determined by, for example, dissolving the polyamide composition or the molded article in an organic solvent, extracting the fibrous filler (C1), and analyzing the image using an electron microscope in the same manner as described above.

Examples of the cross-sectional shapes of the fibrous filler (C1) and the needle-like filler (C2) include a rectangular shape, an oblong shape close to a rectangular shape, an oval shape, a cocoon shape, and a cocoon shape in which the center portion in the longitudinal direction is recessed. Among them, the cross-sectional shapes of the fibrous filler (C1) and the needle-like filler (C2) are preferably rectangular, oblong close to rectangular, oval, or cocoon-shaped.

The fibrous filler (C1) may be surface-treated with a silane coupling agent, a titanate coupling agent, or the like, as necessary. The silane coupling agent is not particularly limited, and examples thereof include: aminosilane-based coupling agents such as γ -aminopropyltriethoxysilane, γ -aminopropyltrimethoxysilane, and N- β - (aminoethyl) - γ -aminopropylmethyldimethoxysilane; mercaptosilane coupling agents such as gamma-mercaptopropyltrimethoxysilane and gamma-mercaptopropyltriethoxysilane; an epoxy silane coupling agent; vinyl silane coupling agents, and the like. These silane coupling agents may be used alone in 1 kind, or may be used in combination in 2 or more kinds. Among the above silane coupling agents, an aminosilicone coupling agent is preferable.

The fibrous filler (C1) may be treated with a sizing agent as needed. Examples of the sizing agent include a copolymer containing, as constituent units, an unsaturated vinyl monomer unit containing a carboxylic anhydride and an unsaturated vinyl monomer unit other than the unsaturated vinyl monomer containing a carboxylic anhydride, an epoxy compound, a urethane resin, a homopolymer of acrylic acid, a copolymer of acrylic acid and another copolymerizable monomer, and salts of these with a primary, secondary or tertiary amine. These sizing agents may be used alone or in combination of two or more.

When the fibrous filler (C1) is a glass fiber, specific examples of the composition include an E glass composition, a C glass composition, an S glass composition, an alkali-resistant glass composition, and the like. The tensile strength of the glass fiber is arbitrary, but is usually 290kg/mm²The above. Among them, E glass is preferable from the viewpoint of easy availability. The glass fibers are preferably surface-treated as described above, and the amount of the glass fibers adhering thereto is usually 0.01 mass% or more based on the mass of the glass fibers (the total amount of the glass fibers and the surface-treating agent).

The content of the filler (C) is preferably 0.1 part by mass or more and 200 parts by mass or less, more preferably 1 part by mass or more and 180 parts by mass or less, and further preferably 5 parts by mass or more and 150 parts by mass or less, with respect to 100 parts by mass of the polyamide (a). By setting the content of the filler (C) to 0.1 part by mass or more per 100 parts by mass of the polyamide (a), the toughness, mechanical strength and the like of the polyamide composition are improved, and by setting the content to 200 parts by mass or less, a polyamide composition having excellent moldability can be obtained.

[ flame retardant auxiliary (D) ]

The polyamide composition of embodiment 4 may contain a flame retardant aid (D). By using the flame retardant auxiliary (D) in combination with the halogen-based flame retardant (B5), the polyamide composition according to embodiment 4 and the molded article formed from the polyamide composition can exhibit more excellent flame retardancy.

Examples of the flame retardant aid (D) include antimony compounds such as antimony oxides such as antimony trioxide, antimony tetraoxide and antimony pentoxide, and antimonates such as sodium antimonate; melamine compounds such as melamine orthophosphate, melamine pyrophosphate, melamine borate and melamine polyphosphate; tin oxides such as tin oxide and tin dioxide; iron oxides such as iron oxide and gamma iron oxide; metal oxides such as aluminum oxide, silicon oxide (silica), titanium oxide, zirconium oxide, manganese oxide, molybdenum oxide, cobalt oxide, bismuth oxide, chromium oxide, tin oxide, nickel oxide, copper oxide, and tungsten oxide; metal hydroxides such as aluminum hydroxide; metal powders of aluminum, iron, titanium, manganese, zinc, molybdenum, cobalt, bismuth, chromium, tin, antimony, nickel, copper, tungsten, and the like; metal carbonates such as zinc carbonate, calcium carbonate, magnesium carbonate, and barium carbonate; metal borates such as zinc borate, calcium borate, and aluminum borate; zinc stannate such as zinc metastannate; silicone, and the like. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Among the above, at least 1 kind selected from antimony-based compounds, melamine-based compounds, metal oxides, metal hydroxides, metal borates and zinc stannate is preferable, and at least 1 kind selected from antimony trioxide, antimony tetraoxide, antimony pentoxide, sodium antimonate, melamine orthophosphate, melamine pyrophosphate, melamine borate, melamine polyphosphate, aluminum oxide, aluminum hydroxide, zinc borate and zinc stannate is more preferable.

The flame-retardant auxiliary (D) is preferably contained in the polyamide composition in the form of a powder. The upper limit of the average particle diameter is preferably 30 μm, more preferably 15 μm, still more preferably 10 μm, and most preferably 7 μm. On the other hand, the lower limit of the average particle diameter of the flame-retardant auxiliary (D) is preferably 0.01. mu.m. When the average particle diameter is 0.01 to 30 μm, the flame retardancy of the obtained polyamide composition is improved.

When the flame-retardant auxiliary (D) is contained, the content thereof is preferably 1 part by mass or more and 30 parts by mass or less, more preferably 1 part by mass or more and 25 parts by mass or less, and further preferably 3 parts by mass or more and 20 parts by mass or less, with respect to 100 parts by mass of the polyamide (a).

The total content of the polyamide (a), the halogen-based flame retardant (B5), the filler (C), and the flame-retardant auxiliary (D) in the polyamide composition according to embodiment 4 is preferably 90 mass% or more, more preferably 92 mass% or more, and may be 95 mass% or more and 97 mass% or more. The total content of the polyamide (a), the halogen-based flame retardant (B5), the filler (C), and the flame-retardant auxiliary (D) in the polyamide composition according to embodiment 4 may be 100 mass%, but is preferably less than 100 mass% in view of the amount of other additives described later added as needed, and may be 99.5 mass% or less and 99 mass% or less.

When the total content of the polyamide (a), the halogen-based flame retardant (B5), the filler (C), and the flame retardant auxiliary (D) in the polyamide composition according to embodiment 4 is within the above range, the polyamide composition is likely to exhibit excellent physical properties such as flame retardancy.

[ optional Components ]

The polyamide composition of embodiment 4 may contain the above-mentioned polyolefin (B1), organic heat stabilizer (B2) (for example, phenol heat stabilizer, phosphorus heat stabilizer, sulfur heat stabilizer, amine heat stabilizer), copper compound (B3) and metal halide (B4) as necessary, in addition to the polyamide (a), halogen-based flame retardant (B5) and filler (C) and flame retardant aid (D) which are used as necessary. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The contents of these (B1), (B2), (B3) and (B4) in the polyamide composition of embodiment 4 are not particularly limited as long as the effects of the present invention are not impaired, and preferred ranges are as described above.

(other additives)

Further, the polyamide composition of embodiment 4 may contain other additives as needed. Examples of the other additives include those similar to the "other additives" in the description of the polyamide composition of embodiment 1.

The content of the other additives is not particularly limited as long as the effect of the present invention is not impaired.

In a preferred embodiment of the polyamide composition according to embodiment 4, the total content of the above-mentioned (B1), (B2), (B3), (B4) and the above-mentioned other additives is preferably 0.02 to 200 parts by mass, more preferably 0.03 to 100 parts by mass, based on 100 parts by mass of the polyamide (a).

< embodiment 5 >

The polyamide composition according to embodiment 5 comprises a polyamide (a) and a halogen-free flame retardant (B6).

As described above, the polyamide (a) has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus has more excellent various physical properties such as chemical resistance, and the polyamide composition of embodiment 5 containing the polyamide (a) and the halogen-free flame retardant (B6) also has the above excellent properties and excellent flame retardancy. In addition, the polyamide composition has a small environmental burden. In addition, various molded articles obtained from the polyamide composition can maintain the excellent properties of the polyamide composition.

[ halogen-free flame retardant (B6) ]

The polyamide composition of the 5 th embodiment contains a halogen-free flame retardant (B6). By containing the halogen-free flame retardant (B6), the flame retardancy of the polyamide composition can be improved while reducing the environmental load.

The halogen-free flame retardant (B6) is not particularly limited, and a compound known as a halogen-free flame retardant can be used. As the halogen-free flame retardant (B6), phosphorus flame retardants containing a phosphorus element can be preferably used, and more specifically, red phosphorus flame retardants, phosphate ester flame retardants, phosphoric acid amide flame retardants, (poly) phosphate flame retardants, phosphazene flame retardants, phosphine flame retardants, and the like can be mentioned. Among them, phosphine-based flame retardants are preferred.

Examples of the phosphine-based flame retardant include a monophosphonate and a diphosphonate (hereinafter, both may be collectively referred to as "phosphinates").

These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Examples of the monophosphonate include compounds represented by the following general formula (1).

[ chemical formula 1]

Examples of the diphosphinate salt include compounds represented by the following general formula (2).

[ chemical formula 2]

In the general formulae (1) and (2), R¹、R²、R³And R⁴Each independently represents an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, R⁵Represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an alkylarylene group having 7 to 20 carbon atoms or an arylalkylene group having 7 to 20 carbon atoms, M represents calcium (ion), magnesium (ion), aluminum (ion) or zinc (ion), M is 2 or 3, n is 1 or 3, and x is 1 or 2.

Examples of the alkyl group include a straight-chain or branched-chain saturated aliphatic group. The above-mentioned aryl group may be unsubstituted or substituted with various substituents, and examples thereof include phenyl, benzyl, o-tolyl, 2, 3-xylyl and the like.

The phosphinate can be prepared in an aqueous solution using phosphinic acid and a metal component such as a metal carbonate, a metal hydroxide, or a metal oxide, as described in, for example, European patent application publication No. 699708 and Japanese patent application laid-open No. 8-73720. They are generally monomeric compounds, but depending on the reaction conditions, they may include polymeric phosphinates having a condensation degree of 1 to 3 depending on the environment.

Examples of the monophosphonic acid and diphosphinic acid constituting the phosphinate include dimethylphosphinic acid, methylethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methanedi (methylphosphinic acid), benzene-1, 4-di (methylphosphinic acid), methylphenylphosphinic acid, diphenylphosphinic acid, and the like.

Examples of the metal component constituting the phosphinate include calcium ions, magnesium ions, aluminum ions, zinc ions, and the like.

Specific examples of the phosphinate include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium methylethylphosphinate, magnesium methylethylphosphinate, aluminum methylethylphosphinate, zinc methylethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, calcium methylenebis (methylphosphinic acid), magnesium methylenebis (methylphosphinic acid), aluminum methylenebis (methylphosphinic acid), zinc methylenebis (methylphosphinic acid), calcium phenylene-1, 4-bis (methylphosphinic acid), magnesium phenylene-1, 4-bis (methylphosphinic acid), Phenylene-1, 4-bis (methylphosphinic acid) aluminum, phenylene-1, 4-bis (methylphosphinic acid) zinc, methylphenylphosphinic acid calcium, methylphenylphosphinic acid magnesium, methylphenylphosphinic acid aluminum, methylphenylphosphinic acid zinc, diphenylphosphinic acid calcium, diphenylphosphinic acid magnesium, diphenylphosphinic acid aluminum, diphenylphosphinic acid zinc, etc.

Among these, calcium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium methylethylphosphinate, aluminum methylethylphosphinate, zinc methylethylphosphinate, calcium diethylphosphinate, aluminum diethylphosphinate, and zinc diethylphosphinate are preferable from the viewpoint of flame retardancy, electrical characteristics, and easiness of obtaining phosphinate of the obtained polyamide composition. These phosphinic acid salts may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The phosphinate is preferably pulverized to a powder having an average particle size of the phosphinate of 100 μm or less, more preferably 50 μm or less, from the viewpoints of mechanical properties (toughness, rigidity, etc.) of the polyamide composition and molded articles formed therefrom, and appearance of the molded articles. The use of a powdery phosphinate having an average particle size of, for example, about 0.5 to 20 μm is preferable because it can provide a polyamide composition having excellent flame retardancy and also can improve the rigidity of a molded article.

In the present specification, the average particle diameter refers to a value measured by a laser diffraction particle size distribution apparatus.

The phosphinate is not necessarily completely pure, and may contain unreacted substances or by-products within a range not impairing the effect of the present invention.

The content of the halogen-free flame retardant (B6) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, further preferably 20 parts by mass or more, and further preferably 25 parts by mass or more, per 100 parts by mass of the polyamide (a). The content of the halogen-free flame retardant (B6) is preferably 100 parts by mass or less, more preferably 75 parts by mass or less, still more preferably 70 parts by mass or less, yet more preferably 50 parts by mass or less, and still more preferably 30 parts by mass or less, per 100 parts by mass of the polyamide (a).

When the content of the halogen-free flame retardant (B6) is not less than the lower limit, a polyamide composition having excellent flame retardancy can be obtained. When the content of the halogen-free flame retardant (B6) is not more than the upper limit, generation of decomposition gas during melt kneading, reduction in fluidity (particularly thin-wall fluidity) during molding, adhesion of a contaminating substance to a molding die, and deterioration of mechanical properties and appearance of a molded article can be suppressed. In the case where a plurality of halogen-free flame retardants (B6) are used, the total amount thereof may fall within the above range.

The total content of the polyamide (a) and the halogen-free flame retardant (B6) in the polyamide composition according to embodiment 5 is more preferably 50 mass% or more, and still more preferably 55 mass% or more. The total content of the polyamide (a) and the halogen-free flame retardant (B6) in the polyamide composition according to embodiment 5 may be 100 mass%, but is preferably less than 100 mass% in consideration of the amount of the filler (C) and other additives added as needed, which will be described later, and may be 90 mass% or less and 80 mass% or less.

According to the studies of the present inventors, it was found that, with respect to a polyamide constituting a polyamide composition, when more than 40 mol% of dicarboxylic acid units constituting the polyamide are naphthalenedicarboxylic acid units, flame retardancy tends to be further improved by the combination of a halogen-free flame retardant and the polyamide as compared with the case where more than 40 mol% of dicarboxylic acid units constituting the polyamide are terephthalic acid units. It has also been found that this tendency is exhibited irrespective of the ratio of the linear aliphatic diamine unit to the branched aliphatic diamine unit in the diamine units constituting the polyamide. Therefore, for example, assuming an application in which only the importance of specific physical properties of the semi-aromatic polyamide is required, when a polyamide composition is produced using a polyamide in which the ratio of the branched aliphatic diamine unit is larger than the ratio of the linear aliphatic diamine unit in the diamine unit and a halogen-free flame retardant, there is a possibility that a polyamide composition having both the above-described specific physical properties and flame retardancy can be formed.

[ Filler (C) ]

The polyamide composition of embodiment 5 may contain a filler (C). By using the filler (C), a polyamide composition excellent in flame retardancy, heat resistance, moldability and mechanical strength in a thin-walled state can be obtained.

The filler (C) is synonymous with the filler (C) described in the polyamide composition of embodiment 4. The preferable embodiment and content of the filler (C) in the polyamide composition of embodiment 5 are also the same as those in the polyamide composition of embodiment 4.

The total content of the polyamide (a), the halogen-free flame retardant (B6), and the filler (C) in the polyamide composition according to embodiment 5 is preferably 90 mass% or more, more preferably 92 mass% or more, and may be 95 mass% or more and 97 mass% or more. The total content of the halogen-free flame retardant (B6) of the polyamide (a) and the filler (C) in the polyamide composition according to embodiment 5 may be 100 mass%, but is preferably less than 100 mass% in view of the amount of other additives described later added as needed, and may be 99.5 mass% or less and 99 mass% or less.

When the total content of the polyamide (a), the halogen-free flame retardant (B6), and the filler (C) in the polyamide composition according to embodiment 5 is within the above range, the polyamide composition is likely to exhibit excellent physical properties such as flame retardancy.

[ optional Components ]

The polyamide composition of embodiment 5 may contain, in addition to the above-mentioned polyamide (a), halogen-free flame retardant (B6) and filler (C) used as needed, the above-mentioned polyolefin (B1), organic heat stabilizer (B2) (for example, phenol heat stabilizer, phosphorus heat stabilizer, sulfur heat stabilizer, amine heat stabilizer), copper compound (B3) and flame retardant aid (D) as needed. These may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The contents of these (B1), (B2), (B3) and (D) in the polyamide composition of embodiment 5 are not particularly limited as long as the effects of the present invention are not impaired, and preferred ranges are as described above. Further, in the polyamide composition of embodiment 5, a metal halide (B4) may be contained within a range not impairing excellent flame retardancy and low environmental load.

Further, the polyamide composition of embodiment 5 may contain other additives as needed. Examples of the other additives include those similar to the "other additives" in the description of the polyamide composition of embodiment 1. In addition, it is preferable that the other additives contain no halogen other than the fluororesin as the anti-dripping agent.

The content of the other additives is not particularly limited as long as the effects of the present invention are not impaired.

As a preferred embodiment of the polyamide composition of embodiment 5, the total content of the above-mentioned (B1), (B2), (B3), (B4), (D) and the above-mentioned other additives is preferably 0.02 to 200 parts by mass, more preferably 0.03 to 100 parts by mass, based on 100 parts by mass of the polyamide (A).

< method for producing Polyamide composition >

The method for producing the polyamide composition is not particularly limited, and a method capable of uniformly mixing the polyamide and the above-mentioned components can be preferably used. In general, a method of melt-kneading using a single-screw extruder, a twin-screw extruder, a kneader, a Banbury mixer, or the like is preferably used for the mixing. The melt-kneading conditions are not particularly limited, and examples thereof include a method of melt-kneading for about 1 to 30 minutes at a temperature of about 10 to 50 ℃ higher than the melting point of the polyamide.

In addition, in the production of the polyamide composition of embodiment 3, examples of the method for adding the copper compound (B3) and the metal halide (B4) to the polyamide (a) include a method in which the copper compound (B3) and the metal halide (B4) are added individually or as a mixture in the polymerization step of the polyamide (a) (hereinafter, may be abbreviated as "production method 1"), and a method in which the polyamide (a), the copper compound (B3), and the metal halide (B4) are added individually or as a mixture in the melt kneading (hereinafter, may be abbreviated as "production method 2").

When the copper compound (B3) and the metal halide (B4) are added, they may be added as solids or in the form of an aqueous solution. As other additives, the same addition method as that of the production method 1 or 2 can be employed. The phrase "in the polymerization step of the polyamide (A)" in the production process 1 means any stage in any step from the starting monomer to the completion of the polymerization of the polyamide (A). In the case of performing the "melt kneading" of the production method 2, the above-mentioned usual melt kneading may be used for the mixing.

[ molded article ]

(Molding method)

The molded article made of the polyamide (a) or the polyamide composition of the present invention can be obtained by molding the polyamide (a) or the polyamide composition of the present invention by various molding methods such as injection molding, blow molding, extrusion molding, compression molding, stretch molding, vacuum molding, foam molding, rotational molding, impregnation, laser sintering, and hot melt lamination. Further, the polyamide (a) or the polyamide composition of the present invention may be subjected to composite molding with another polymer or the like to obtain a molded article.

(use)

Examples of the molded article include films, sheets, hoses, tubes, gears, cams, various housings, rollers, impellers, bearing retainers, spring seats, clutch parts, chain tensioners, tanks, tires, connectors, switches, sensors, sockets, capacitors, hard disk parts, jacks, fuse holders, relays, coil bobbins, resistors, IC housings, LED reflectors, and the like.

The polyamide (a) or the polyamide composition of the present invention is suitable as an injection-molded member, a heat-resistant film, a hose for transporting various chemicals/chemical solutions, an inlet pipe, an air leak pipe, a base material for a 3D printer, etc. which require high-temperature characteristics and chemical resistance, and can be suitably used for molded articles for automobile applications, such as interior and exterior parts of automobiles, parts in engine rooms, cooling system parts, sliding parts, electric parts, etc., which require high heat resistance and chemical resistance. Further, the polyamide (A) or the polyamide composition of the present invention can be formed into electric parts, electronic parts; a molded article having heat resistance corresponding to surface mounting engineering is required. Such molded articles can be suitably used for surface-mounted components such as electric parts, electronic parts, surface-mounted connectors, sockets, camera modules, power supply parts, switches, sensors, capacitor base plates, hard disk parts, relays, resistors, fuse holders, bobbins, and IC cases.

Examples

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto.

The evaluation in examples and comparative examples was performed by the following methods.

Intrinsic viscosity

The intrinsic viscosity (dl/g) at a temperature of 30 ℃ and a concentration of 0.2g/dl in concentrated sulfuric acid as a solvent was obtained from the polyamides (samples) obtained in examples 1 to 3 and comparative examples 1 to 4 by the following relational expression.

η_inh＝[1n(t₁/t₀)]/c

In the above relation, eta_inhDenotes intrinsic viscosity (dl/g), t₀The flow-down time (sec) of the solvent (concentrated sulfuric acid) is shown by t₁The flow-down time (sec) of the sample solution is shown, and c represents the concentration (g/dl) of the sample in the sample solution (i.e., 0.2 g/dl).

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in examples 1 to 3 and comparative examples 1 to 4 were measured by using a differential scanning calorimetry apparatus "DSC 7020" manufactured by Hitachi High-Tech Science, Ltd.

Melting points were determined according to ISO11357-3(2011 version 2). Specifically, the sample (polyamide) was heated at a rate of 10 ℃/min from 30 ℃ to 340 ℃ under a nitrogen atmosphere, and after the sample was completely melted by holding at 340 ℃ for 5 minutes, the sample was cooled at a rate of 10 ℃/min to 50 ℃ and held at 50 ℃ for 5 minutes. The melting point (. degree.C.) was defined as the peak temperature of the melting peak occurring when the temperature was again raised to 340 ℃ at a rate of 10 ℃ per minute, and the melting point (. degree.C.) was defined as the peak temperature of the melting peak on the highest temperature side when a plurality of melting peaks were present.

The glass transition temperature (. degree. C.) was measured in accordance with ISO11357-2(2013, 2 nd edition). Specifically, the sample (polyamide) was heated at a rate of 20 ℃/min from 30 ℃ to 340 ℃ under a nitrogen atmosphere, and after the sample was completely melted by holding at 340 ℃ for 5 minutes, it was cooled at a rate of 20 ℃/min to 50 ℃ and held at 50 ℃ for 5 minutes. The temperature at the inflection point appearing when the temperature was raised again to 200 ℃ at a rate of 20 ℃/min was taken as the glass transition temperature (. degree. C.).

Preparation of test piece

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industries, the polyamide compositions obtained in examples 1 to 3 and comparative examples 1 to 4 were molded at a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the polyamide compositions of examples 1 to 3 and comparative examples 1 and 2 were molded at a mold temperature of 160 ℃ and at a mold temperature of 140 ℃ using a T-type casting mold to obtain a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Percentage of weight increase after immersion in antifreeze

The multifunctional test piece a1 type (4mm thick) produced by the above-described method was weighed, immersed in an antifreeze solution (an aqueous solution prepared by diluting "ultralong-life coolant" (pink) manufactured by toyota corporation) at 130 ℃ for 500 hours, and then weighed again to determine the weight increase, and the weight increase (%) after immersion was determined by dividing the weight increase by the weight before immersion.

Retention of tensile Strength

Using the multifunctional test piece a1 type (4mm thick) produced by the above method, a tensile test was performed at 23 ℃ in accordance with ISO527-1(2 nd edition 2012), and the tensile breaking strength was calculated by the following formula (1). The value was set as the initial tensile break strength (a).

Tensile breaking strength (MPa) breaking point stress (N)/test piece sectional area (mm)²)(1)

The test piece produced by the above-described method was immersed in an antifreeze solution (an aqueous solution obtained by diluting "ultra-long-life coolant" (pink) manufactured by toyota car corporation) 2 times) in a pressure-resistant container, and the pressure-resistant container was allowed to stand in a thermostat set at 130 ℃ (DE-303 manufactured by mitania corporation) for 500 hours. After 500 hours, the test piece taken out of the thermostatic bath was subjected to a tensile test in the same manner as described above, and the tensile breaking strength (b) of the heated test piece was measured.

The tensile strength retention was determined by the following formula (2), and the long-term heat resistance and chemical resistance were evaluated.

Tensile strength retention (%) { (b)/(a) } × 100 (2)

Tensile break strength and flexural Strength

Using the multifunctional test piece a1 type (4mm thick) produced by the above method, the tensile break strength (MPa) and the flexural strength (MPa) at 23 ℃ were measured according to ISO527-1(2 nd edition 2012) for the tensile break strength and ISO178 (4 th edition 2001) for the flexural strength, respectively.

Heat distortion temperature

Test pieces (4mm thick, 80mm in full length, 10mm in width) were prepared by cutting a multifunctional test piece a1 type (4mm thick) prepared by the above-described method, and the heat distortion temperature (c) was measured according to ISO75 (3 rd edition 2013) using an HDT tester "S-3M" manufactured by tokyo seiki koku kokai.

Water absorption

A model A1 (4mm thick) of the multifunctional test piece produced by the above-described method was weighed. Subsequently, the sheet was immersed in water, immersed at 23 ℃ for 168 hours, weighed again to determine the weight gain, and divided by the weight before immersion to determine the water absorption (%).

Preparation of film

Using LABO PLASTOMILL (phi 20mm, L/D25, full-flight screw) manufactured by Tokyo Seiko, Ltd., using the polyamide compositions obtained in examples 1 to 3 and comparative examples 1 to 4, films having a thickness of 200 μm. + -. 20 μm were manufactured using a T die (width 150mm, die lip width 0.4mm) at a cylinder temperature and a die temperature 20 to 30 ℃ higher than the melting point of the polyamide.

Storage modulus and loss tangent (α relaxation temperature)

From the film produced by the above method, a strip test piece having a length of 40mm and a width of 10mm was cut out with the MD direction as the longitudinal side, and the cut piece was prepared using "EXSTAR DMS 6100" manufactured by hitachi High-Tech Science in accordance with ISO 6721: 1994, measured at 10.0Hz at a temperature rise rate of 3 ℃/min in a tensile mode under a nitrogen atmosphere, and the storage moduli (GPa) at 23 ℃ and 150 ℃ were determined. The peak temperature (c) of the loss tangent was determined as an α relaxation temperature.

[ example 1]

(1) Production of semi-aromatic Polyamide (PA9N-1)

9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 8.3 liters of distilled water were placed in an autoclave having an internal volume of 40 liters, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N-1".

(2) Production of Polyamide composition

PA9N-1 and other components (antioxidant, lubricant, and crystal nucleating agent) shown below were mixed in advance at the ratio shown in Table 1, and then fed into an upstream supply port of a twin-screw extruder ("TEM-26 SS", Toshiba machine Co., Ltd.). The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

[ example 2]

(1) Production of semi-aromatic Polyamide (PA9N-2)

A polyamide was obtained in the same manner as in example 1 except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 15/85 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N-2".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9N-2 was used as the polyamide.

[ example 3]

(1) Production of semi-aromatic Polyamide (PA9N-3)

A polyamide was obtained in the same manner as in example 1 except that 5296.7g (24.50 moles) of 2, 6-naphthalenedicarboxylic acid, 3772.8g (25.18 moles) of a mixture of 1, 6-nonanediamine and 2-methyl-1, 8-octanediamine [ the former/the latter ] ═ 20/80 (mole ratio) ], 122.1g (1.00 moles) of benzoic acid, 9.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 4.1 liters of distilled water were used as raw materials. The polyamide was abbreviated as "PA 9N-3".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9N-3 was used as the polyamide.

Comparative example 1

(1) Production of semi-aromatic Polyamide (PA9N-4)

A polyamide was obtained in the same manner as in example 1 except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 50/50 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N-4".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9N-4 was used as the polyamide.

Comparative example 2

(1) Production of semi-aromatic Polyamide (PA9N-5)

A polyamide was obtained in the same manner as in example 1 except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 85/15 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N-5".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9N-5 was used as the polyamide.

Comparative example 3

(1) Production of semi-aromatic Polyamide (PA9T-1)

An autoclave having an internal volume of 40 liters was charged with 8190.7g (49.30 moles), 7969.4g (50.35 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 171.0g (1.40 moles) of benzoic acid, 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 5.5 liters of distilled water, and then a polyamide was obtained in the same manner as in example 1. The polyamide was abbreviated as "PA 9T-1".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9T-1 was used as the polyamide.

Comparative example 4

(1) Production of semi-aromatic Polyamide (PA9T-2)

A polyamide was obtained in the same manner as in comparative example 3, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 80/20 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9T-2".

(2) Production of Polyamide composition

A granular polyamide composition was produced in the same manner as in example 1, except that the above PA9T-2 was used as the polyamide.

Other ingredients

An antioxidant

Sumilizer GA-80, manufactured by Sumitomo chemical Co., Ltd

Slip agent

"LICOWAX OP", manufactured by Clariant Chemicals

Nucleating agents for crystals

"TALC ML 112" manufactured by Fuji TALC

[ Table 1]

TABLE 1

	Unit of	Percentage of
			Polyamide	Mass portion of	100
Antioxidant SUMILIZER GA-80	Mass portion of	0.2
			Licowax OP as a lubricant	Mass portion of	0.2
Crystal nucleating agent TALC ML112	Mass portion of	0.1

The polyamide compositions obtained in examples 1 to 3 and comparative examples 1 to 4 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 2.

In Table 2, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 2]

As is apparent from Table 2, the polyamide compositions of examples 1 to 3 have a lower weight increase rate after immersion in the antifreeze and an excellent tensile strength retention rate after immersion in the antifreeze than those of comparative examples 1 to 4. From these results, it is understood that the polyamide of the present invention and the polyamide composition containing the same are excellent in chemical resistance (particularly long-term heat resistance and chemical resistance).

The polyamide compositions of examples 1 to 3 are excellent in the respective evaluation results of tensile breaking strength, flexural strength, heat distortion temperature, water absorption rate and storage modulus, excellent in high-temperature strength, mechanical properties, heat resistance and low water absorption, and more excellent in the overall balance thereof than comparative examples 1 to 4.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. On the other hand, the polyamide of the present invention has a specific structure containing a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus further improves chemical resistance, and further improves high-temperature strength, mechanical properties, heat resistance, and low water absorption property, and further has various excellent physical properties such as chemical resistance.

Example 4 and comparative examples 5 to 7

Polyamides were produced using 2, 6-naphthalenedicarboxylic acid as the dicarboxylic acid and 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine as the diamines so as to have the molar ratios shown in table 3, and the melting points and glass transition temperatures of the produced polyamides are shown in table 3 together with the melting points and glass transition temperatures of the polyamides obtained in examples 1 and 2 and comparative examples 1 and 2.

In addition, as shown in FIG. 1, a graph was prepared in which the melting point (. degree. C.) of the polyamide was plotted against the content ratio (% by mol) of the 2-methyl-1, 8-octanediamine unit in the diamine unit.

The production methods of the polyamides of example 4 and comparative examples 5 to 7 were performed in the same manner as in example 1, and the melting point and the glass transition temperature were measured in the same manner as described above.

In Table 3, 2, 6-NDA represents a2, 6-naphthalenedicarboxylic acid unit, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 3]

[ Polyamide composition of embodiment 1]

Next, the polyamide composition of embodiment 1 will be described more specifically by way of examples and comparative examples, but the polyamide composition is not limited thereto.

Each evaluation in the production examples, examples and comparative examples was performed according to the method shown below.

Intrinsic viscosity

The intrinsic viscosity of the polyamide (sample) obtained in production examples 1-1 to 1-5 was determined in the same manner as in the above-described calculation method.

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in production examples 1-1 to 1-5 were determined in the same manner as in the above-described measurement methods.

Preparation of test piece 2

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industry Co., Ltd., the polyamide compositions obtained in examples and comparative examples were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of polyamide, and the polyamide compositions of examples 5 to 8 and comparative examples 8 and 9 were molded using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to prepare a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Chemical resistance (weight gain after immersion in antifreeze)

The multifunctional test piece A1 type (4mm thick) produced by the method of production 2 of the test piece was used and was obtained in the same manner as the above-described measurement method (immersion treatment at 130 ℃ C. for 500 hours).

Chemical resistance (tensile Strength Retention)

The multifunctional test piece A1 type (4mm thick) produced by the method of production 2 of the test piece was used and was obtained in the same manner as the above-described measurement method (immersion treatment at 130 ℃ C. for 500 hours).

Impact resistance

Test pieces (4mm thick, 80mm in total length, 10mm in width, and notched) were prepared by cutting a multifunctional test piece A1 type (4mm thick) prepared by the method of preparation 2 of the above test piece, and impact resistance (kJ/m) was evaluated by measuring notched Charpy impact values at 23 ℃ and-40 ℃ using a Charpy impact tester (manufactured by Tokyo Seisakusho K.K.) in accordance with ISO179-1(2 nd edition 2010), namely, a Charpy impact tester (manufactured by Tokyo Seiki Seisaku Kogyo Co., Ltd.)²)。

Heat distortion temperature

The multifunctional test piece a1 type (4mm thick) produced by the method of producing the test piece 2 was used, and was obtained in the same manner as the above measurement method.

Tensile breaking Strength

The multifunctional test piece a1 type (4mm thick) produced by the method of producing the test piece 2 was used, and was obtained in the same manner as the above measurement method.

Strain at tensile break

The multifunctional test piece a1 type (4mm thick) produced by the method of production 2 of the above test piece was used to measure the tensile strain at break (%) at 23 ℃ in accordance with ISO527-1(2 nd edition 2012).

Water absorption

The multifunctional test piece a1 type (4mm thick) produced by the method of producing the test piece 2 was used, and was obtained in the same manner as the above measurement method.

The respective ingredients used for preparing the polyamide compositions of examples and comparative examples are shown.

Polyamides (polyamides)

Production example 1-1

Production of semi-aromatic Polyamide (PA9N1-1)

9611.8g (44.46 moles) of 2, 6-naphthalenedicarboxylic acid, 7158.2g (45.23 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 131.9g (1.08 moles) of benzoic acid, 16.9g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 7.3 liters of distilled water were placed in an autoclave containing 40 liters of an internal solvent, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N 1-1".

Production examples 1 and 2

Production of semi-aromatic Polyamide (PA9N1-1B)

A polyamide was obtained in the same manner as in production example 1-1 except that 9175.3g (42.44 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ the former/the latter ] ═ 4/96 (molar ratio), 136.5g (1.12 moles) of benzoic acid, and 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate were used as raw materials. The polyamide was abbreviated as "PA 9N 1-1B".

Production examples 1 to 3

Production of semi-aromatic Polyamide (PA9N1-2)

A polyamide was obtained in the same manner as in production example 1-1 except that 9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ the former/the latter ] ═ 15/85 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, and 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate were used as raw materials. The polyamide was abbreviated as "PA 9N 1-2".

Production examples 1 to 4

Production of semi-aromatic Polyamide (PA9N1-3)

A polyamide was obtained in the same manner as in production example 1-1 except that 9379.2g (43.38 mol) of 2, 6-naphthalenedicarboxylic acid, 6999.1g (44.22 mol) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ the former/the latter ] ═ 85/15 (mol ratio) ], 150.5g (1.23 mol) of benzoic acid, and 16.5g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate were used as raw materials. The polyamide was abbreviated as "PA 9N 1-3".

Production examples 1 to 5

Production of semi-aromatic Polyamide (PA9T1-1)

A polyamide was obtained in the same manner as in production example 1-1, except that 8190.7g (49.30 moles) of terephthalic acid, 7969.4g (50.35 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ the former/the latter ] ═ 80/20 (molar ratio) ], 171.0g (1.40 moles) of benzoic acid, and 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate were used as raw materials. The polyamide was abbreviated as "PA 9T 1-1".

Polyolefins

Modified Polymer (EPR)

"TAFMER MP 0620", a modified polymer obtained by modifying an ethylene-propylene copolymer with maleic anhydride, manufactured by Mitsui chemical Co., Ltd

Modified Polymer (SEBS)

"Tuftec M1943", a modified polymer of Asahi Kasei Kogyo, styrene-ethylene-butene copolymer modified with maleic anhydride

Other additives

Antioxidant (1)

KG HS01-P manufactured by PolyAd Services

Antioxidant (2)

Sumilizer GA-80, manufactured by Sumitomo chemical Co., Ltd

Slip agent

"LICOWAX OP", manufactured by Clariant Chemicals

Nucleating agents for crystals

"TALC ML 112" manufactured by Fuji TALC

Colorants

Carbon Black "# 980B" manufactured by Mitsubishi chemical corporation

Examples 5 to 8 and comparative examples 8 to 11

The respective components were mixed in advance at the ratios shown in Table 4, and collectively charged into an upstream supply port of a twin-screw extruder ("TEM-26 SS" manufactured by Toshiba machine Co., Ltd.). The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

The polyamide compositions obtained in examples 5 to 8 and comparative examples 8 to 11 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 1.

In Table 4, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 4]

As is clear from Table 4, the polyamide compositions of examples 5 to 8 have excellent impact resistance, heat resistance and chemical resistance in combination, and also have excellent mechanical properties and low water absorption.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. On the other hand, the polyamide composition of embodiment 1, which contains the polyamide (a) having a specific structure containing a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, has further improved chemical resistance and further has various excellent physical properties such as impact resistance, heat resistance, mechanical properties, and low water absorption.

[ Polyamide composition of embodiment 2]

Next, the polyamide composition of embodiment 2 will be described more specifically with reference to examples and comparative examples, but the polyamide composition is not limited thereto.

Each evaluation in the production examples, examples and comparative examples was performed according to the method shown below.

Intrinsic viscosity

The intrinsic viscosity of the polyamide (sample) obtained in production examples 2-1 to 2-6 was determined in the same manner as in the above-described calculation method.

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in production examples 2-1 to 2-6 were determined in the same manner as in the above-described measurement methods.

Preparation of test piece 3

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industries, the polyamide compositions obtained in examples 9 to 13 and comparative examples 12 to 16 were molded at a cylinder temperature 20 to 30 ℃ higher than the melting point of polyamide, and the polyamide compositions of examples 9 to 13 and comparative examples 12 and 16 were molded at a mold temperature of 160 ℃ and at a mold temperature of 140 ℃ using a T-type casting mold to prepare a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Tensile breaking Strength

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 3 was used, and was obtained in the same manner as the above-described measurement method.

Chemical resistance (tensile Strength Retention)

The multifunctional test piece A1 type (4mm thick) produced by the method of production of test piece 3 was used and was obtained in the same manner as the above-described measurement method (immersion treatment at 130 ℃ C. for 500 hours).

Heat distortion temperature

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 3 was used, and was obtained in the same manner as the above-described measurement method.

Water absorption

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 3 was used, and was obtained in the same manner as the above-described measurement method.

Thermal aging resistance

Using the polyamide compositions obtained in examples 9 to 13 and comparative examples 12 to 16, a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide was set using a small kneader/extrusion molding machine ("Xplore MC 15") manufactured by Xplore Instruments, and the polyamide compositions were molded using a T-type casting die at a die temperature of 170 ℃ to prepare small test pieces 1BA type (2mm thick, 75mm in total length, 30mm in parallel portion length, and 5mm in parallel portion width). The tensile strength of this small test piece 1BA type (2mm thick) after standing still in a dryer at 120 ℃ for 500 hours was measured in accordance with ISO527-1(2 nd edition in 2012), and the ratio (%) to the tensile strength of the test piece before standing still in the dryer was calculated to be used as an index of the heat aging resistance.

The respective ingredients used for preparing the polyamide compositions of examples and comparative examples are shown.

Polyamides (polyamides)

Production example 2-1

Production of semi-aromatic Polyamide (PA9N2-1)

9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 8.3 liters of distilled water were placed in an autoclave containing 40 liters of an internal solvent, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N 2-1".

Production example 2-2

Production of semi-aromatic Polyamide (PA9N2-1B)

A polyamide was obtained in the same manner as in production example 2-1, except that the charged amounts of the raw materials were 9175.3g (42.44 mol) of 2, 6-naphthalenedicarboxylic acid and 136.5g (1.12 mol) of benzoic acid. The polyamide was abbreviated as "PA 9N 2-1B".

Production examples 2 to 3

Production of semi-aromatic Polyamide (PA9N2-2)

A polyamide was obtained in the same manner as in production example 2-1, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 15/85 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N 2-2".

Production examples 2 to 4

Production of semi-aromatic Polyamide (PA9N2-3)

A polyamide was obtained in the same manner as in production example 2-1, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 85/15 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N 2-3".

Production examples 2 to 5

Production of semi-aromatic Polyamide (PA9T2-1)

A polyamide was obtained in the same manner as in production example 2-1 except that 8190.7g (49.30 moles), 7969.4g (50.35 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 171.0g (1.40 moles) of benzoic acid, 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 5.5 liters of distilled water were used as raw materials. The polyamide was abbreviated as "PA 9T-1".

Production examples 2 to 6

Production of semi-aromatic Polyamide (PA9T2-2)

A polyamide was obtained in the same manner as in production example 2-4 except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 80/20 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9T 2-2".

Organic heat stabilizer

Sumilizer GA-80, manufactured by Sumitomo chemical Co., Ltd

"NAUGARD 445", manufactured by ADDIVANT CORPORATION

Other additives

Glass fibers

"CS 03JA-FT 2A", manufactured by Owenscorng Japan contract Ltd

(average fiber diameter: 10.5 μm, average fiber length: 3mm, cross-sectional shape: circular)

Slip agent

"LICOWAX OP", manufactured by Clariant Chemicals

Nucleating agents for crystals

"TALC ML 112", manufactured by Fuji TALC

Colorants

Carbon Black "# 980B" manufactured by Mitsubishi chemical corporation

Examples 9 to 13 and comparative examples 12 to 16

The components except for the glass fiber were previously mixed at the ratio shown in table 5, and fed from a hopper at the upstream of a twin-screw extruder ("TEM-26 SS" manufactured by toshiba corporation), and in the case of using the glass fiber, fed from a side inlet at the downstream side of the extruder at the ratio shown in table 5. The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

The polyamide compositions obtained in examples 9 to 13 and comparative examples 12 to 16 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 1.

In Table 5, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 5]

As is apparent from Table 5, the polyamide compositions of examples 9 to 13 have higher tensile strength retention after immersion in an antifreeze solution and further improved chemical resistance as compared with comparative examples 12 to 15. Further, it is found that the polyamide compositions of examples 9 to 13 have excellent heat aging resistance and thus excellent high-temperature heat resistance as compared with comparative example 16.

It is also clear that the polyamide compositions of examples 9 to 13 are excellent in the evaluation of tensile breaking strength, heat distortion temperature and water absorption rate, and are equal to or more than those of comparative examples 12 to 16, and that the polyamide composition of embodiment 2 is also excellent in mechanical properties, heat resistance and low water absorption.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. On the other hand, the polyamide composition of embodiment 2, which contains the polyamide (a) having a specific structure containing a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, has further improved chemical resistance and further has excellent mechanical properties, heat resistance including high-temperature heat resistance, and various physical properties including low water absorption.

[ Polyamide composition of embodiment 3]

Next, the polyamide composition of embodiment 3 will be described more specifically with reference to examples and comparative examples, but the polyamide composition is not limited thereto.

Each evaluation in the production examples, examples and comparative examples was performed according to the method shown below.

Intrinsic viscosity

The intrinsic viscosity of the polyamides (samples) obtained in production examples 3-1 to 3-5 was determined in the same manner as in the above-described calculation method.

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in production examples 3-1 to 3-5 were determined in the same manner as in the above-described measurement methods.

Preparation of test piece 4

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industries, the polyamide compositions obtained in examples 14 and 15 and comparative examples 17 to 21 were molded at a cylinder temperature 20 to 30 ℃ higher than the melting point of polyamide, and the polyamide compositions of examples 14 and 15 and comparative examples 17 and 21 were molded at a mold temperature of 160 ℃ and at a mold temperature of 140 ℃ using a T-type casting mold, to prepare a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Tensile breaking Strength

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 4 was used, and was obtained in the same manner as the above-described measurement method.

Chemical resistance (tensile Strength Retention)

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 4 was used and was obtained in the same manner as the above-described measurement method (immersion treatment at 130 ℃ C. for 500 hours).

Heat distortion temperature

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 4 was used, and was obtained in the same manner as the above-described measurement method.

Water absorption

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 4 was used, and was obtained in the same manner as the above-described measurement method.

Thermal aging resistance type

Using the polyamide compositions obtained in examples 14 and 15 and comparative examples 17 to 21, a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide was set using a small kneader/extrusion molding machine ("Xplore MC 15") manufactured by Xplore Instruments, and the polyamide compositions were molded using a T-type casting die at a die temperature of 170 ℃ to prepare small test pieces 1BA type (2mm thick, 75mm in total length, 30mm in parallel portion length, and 5mm in parallel portion width). The tensile strength of this small test piece 1BA type (2mm thick) after standing in a dryer at 170 ℃ for 250 hours was measured in accordance with ISO527-1(2 nd edition in 2012), and the ratio (%) to the tensile strength of the test piece before standing in the dryer was calculated to be used as an index of the heat aging resistance.

The respective ingredients used for preparing the polyamide compositions of examples and comparative examples are shown.

Polyamides (polyamides)

Production example 3-1

Production of semi-aromatic Polyamide (PA9N3-1)

9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 8.3 liters of distilled water were placed in an autoclave containing 40 liters of an internal solvent, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N 3-1".

Production example 3-2

Production of semi-aromatic Polyamide (PA9N3-2)

A polyamide was obtained in the same manner as in production example 3-1, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 15/85 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N 3-2".

Production examples 3 to 3

Production of semi-aromatic Polyamide (PA9N3-3)

A polyamide was obtained in the same manner as in production example 3-1, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 85/15 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9N 3-3".

Production examples 3 to 4

Production of semi-aromatic Polyamide (PA9T3-1)

An autoclave having an internal volume of 40 liters was charged with 8190.7g (49.30 mol) of terephthalic acid, 7969.4g (50.35 mol) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (mol ratio) ], 171.0g (1.40 mol) of benzoic acid, 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 5.5 liters of distilled water, and then a polyamide was obtained in the same manner as in production example 3-1. The polyamide was abbreviated as "PA 9T 3-1".

Production examples 3 to 5

Production of semi-aromatic Polyamide (PA9T3-2)

A polyamide was obtained in the same manner as in production example 3-4, except that a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine in a ratio [ former/latter: 80/20 (molar ratio) ] was used. The polyamide was abbreviated as "PA 9T 3-2".

Copper compound and metal halide

"KG HS 01-P" (molar ratio: CuI/KI 10/1), manufactured by PolyAd Services

Other additives

Glass fibers

"CS 03JA-FT 2A", manufactured by Owenscorng Japan contract Ltd

(average fiber diameter: 10.5 μm, average fiber length: 3mm, cross-sectional shape: circular)

Slip agent

"LICOWAX OP", manufactured by Clariant Chemicals

Nucleating agents for crystals

"TALC ML 112" manufactured by Fuji TALC

Colorants

Carbon Black "# 980B" manufactured by Mitsubishi chemical corporation

Examples 14 and 15 and comparative examples 17 to 21

The respective components were mixed in advance at the ratio shown in Table 6, and collectively charged into an upstream supply port of a twin-screw extruder ("TEM-26 SS" manufactured by Toshiba machine Co., Ltd.). In the case of using glass fibers, the materials were fed from a side inlet on the downstream side of the extruder at the ratio shown in table 6. The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

The polyamide compositions obtained in examples 14 and 15 and comparative examples 17 to 21 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 6.

In Table 6, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 6]

As is apparent from Table 6, the polyamide compositions of examples 14 and 15 have higher retention of tensile strength after immersion in an antifreeze solution and further improved chemical resistance as compared with comparative examples 17 to 20. Further, it is understood that the polyamide compositions of examples 14 and 15 are excellent in heat aging resistance and thus have excellent high-temperature heat resistance as compared with comparative example 21.

It is also understood that the polyamide compositions of examples 14 and 15 are excellent in the evaluation of tensile strength at break, heat distortion temperature and water absorption rate, and are equal to or more than those of comparative examples 17 to 21, and the polyamide composition of embodiment 3 is also excellent in mechanical properties, heat resistance and low water absorption.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. On the other hand, the polyamide composition of embodiment 3, which contains the polyamide (a) having a specific structure containing a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, has further improved chemical resistance and further has excellent mechanical properties, heat resistance including high-temperature heat resistance, and various physical properties including low water absorption.

[ Polyamide composition of embodiment 4]

Next, the polyamide composition of embodiment 4 will be described more specifically with reference to examples and comparative examples, but the polyamide composition is not limited thereto.

Each evaluation in the production examples, examples and comparative examples was performed according to the method shown below.

Intrinsic viscosity

The intrinsic viscosity of the polyamides (samples) obtained in production examples 4-1 to 4-2 was determined in the same manner as in the above-described calculation method.

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in production examples 4-1 to 4-2 were determined in the same manner as in the above-described measurement methods.

Flame retardancy

The flame retardancy was evaluated in accordance with the specification of UL-94.

Using an injection molding machine (mold clamping force: 80 ton, screw diameter: phi 26mm) manufactured by Nichisu resin industries, the polyamide compositions obtained in example 16 and comparative examples 22 to 24 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of polyamide, and the polyamide compositions of example 16 and comparative example 22 were molded using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to obtain test pieces having a thickness of 0.75mm, a width of 13mm and a length of 125 mm.

Subsequently, the upper end of the obtained test piece was held by a holder and the test piece was vertically fixed, and a predetermined blue flame having a height of 20 ± 1mm was separated from the lower end of the test piece by being brought into contact with the lower end of the test piece for 10 seconds, and the combustion time of the test piece was measured (1 st time). Immediately after flame-out, the flame was again brought into contact with the lower end of the test piece and removed, and the burning time of the test piece was measured (2 nd time). The same measurement was repeated for 5 tablets to obtain 5 data of the 1 st combustion time and 5 data of the 2 nd combustion time, and 10 data were obtained in total. The total of 10 data is T, and the maximum of 10 data is M, and evaluation is performed according to the following evaluation criteria.

Further, it was visually confirmed whether or not the flame was dropped.

[ evaluation criteria ]

V-0: t is 50 seconds or less, M is 10 seconds or less, and the cotton does not burn to the holder and does not ignite 12 inches of cotton even if the melt with flame falls.

V-1: t is 250 seconds or less, M is 30 seconds or less, and the cotton does not burn to the holder and does not ignite under 12 inches even if the melt with flame falls.

V-2: t is below 250 seconds, M is below 30 seconds, there is no burning to the holder, and the melt with the flame falls to ignite the cotton at 12 inches.

X: none of the above evaluation criteria of UL94 is satisfied.

Resistance to foaming

Using an injection molding machine (mold clamping force: 18 ton, screw diameter: 18mm) manufactured by Sumitomo heavy machinery industry Co., Ltd., the polyamide compositions obtained in example 16 and comparative examples 22 to 24 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the polyamide compositions of example 16 and comparative example 22 were molded (extrusion-molded) using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to prepare test pieces (sheets) having a length of 30mm, a width of 10mm and a thickness of 1 mm.

The obtained test piece was allowed to stand at 85 ℃ and 85% relative humidity for 168 hours. Thereafter, the test piece was subjected to a reflow test using an infrared heating furnace (SMT Scope, manufactured by shanyang seiki co., ltd.). In the reflux test, it took 60 seconds to heat up from 25 ℃ to 150 ℃, then 90 seconds to heat up to 180 ℃, and then 60 seconds to heat up to the peak temperature, and held at the peak temperature for 20 seconds. For the reflux test, the peak temperature was varied from 250 ℃ to 270 ℃ on a scale of 10 ℃. After the reflow test was completed, the appearance of the test piece was visually observed. The temperature at the limit where the test piece did not melt and no foaming occurred was defined as the foaming resistance temperature, and the case where the foaming resistance temperature exceeded 260 ℃ was defined as "o", the case where the foaming resistance temperature was 250 ℃ or more and 260 ℃ or less was defined as "Δ", and the case where the foaming resistance temperature was less than 250 ℃ was defined as "x", which was used as an index of the foaming resistance. The results were "O" and "Δ", and the results were found to be practically unproblematic levels.

Preparation of test piece 5

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industry Co., Ltd., the polyamide compositions obtained in example 16 and comparative examples 22 to 24 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the polyamide compositions of example 16 and comparative example 22 were molded using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to prepare a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Tensile breaking Strength

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 5 was used, and was obtained in the same manner as the above-described measurement method.

Heat distortion temperature

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 5 was used, and was obtained in the same manner as the above-described measurement method.

Water absorption

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 5 was used, and was obtained in the same manner as the above-described measurement method.

The respective ingredients used for preparing the polyamide compositions of examples and comparative examples are shown.

Polyamides (polyamides)

Production example 4-1

Production of semi-aromatic Polyamide (PA9N4-1)

9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 8.3 liters of distilled water were placed in an autoclave containing 40 liters of an internal solvent, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N 4-1".

Production example 4-2

Production of semi-aromatic Polyamide (PA9T4-1)

An autoclave having an internal volume of 40 liters was charged with 8190.7g (49.30 mol) of terephthalic acid, 7969.4g (50.35 mol) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 85/15 (mol ratio) ], 171.0g (1.40 mol) of benzoic acid, 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 5.5 liters of distilled water, and then a polyamide was obtained in the same manner as in production example 4-1. The polyamide was abbreviated as "PA 9T 4-1".

Halogen-based flame retardant

Poly (styrene bromide) modified with glycidyl methacrylate (Firemaster CP-44HF, manufactured by Chemtura corporation, bromine content: 64%)

Filler (filler)

Glass fiber (CS-3G 225S manufactured by Nidong textile Co., Ltd.)

(average fiber diameter: 9.5 μm, average fiber length: 3mm, cross-sectional shape: circular)

Flame-retardant auxiliary

Zinc metastannate (Flamantard S manufactured by William Blythe Co.)

(average particle diameter: 1.4 to 2.2 μm)

Other additives

Thermal stabilizers

Phenol heat stabilizer (SUMILIZER GA-80, manufactured by Sumitomo chemical Co., Ltd.)

Slip agent

Low molecular weight polyolefin slip agent ("HiWAX 200P" manufactured by Mitsui Kabushiki Kaisha)

Nucleating agents for crystals

Talc (TALC #5000S manufactured by Fuji TALC industries, Ltd.)

Anti-dripping agent

Fluororesin powder (Teflon (registered trademark) 640J manufactured by Chemours-Mitsui fluoropolymers Co., Ltd.)

Example 16 and comparative examples 22 to 24

The components except for the filler were previously mixed at the ratio shown in table 7, and fed from a hopper at the upstream side of a twin-screw extruder ("BTN-32" by strain engineering) and the filler was fed from a side inlet at the downstream side of the extruder at the ratio shown in table 7. The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

The polyamide compositions obtained in example 16 and comparative examples 22 to 24 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 1.

In Table 7, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 7]

As is clear from Table 7, the polyamide composition of example 16 is excellent in flame retardancy as compared with comparative examples 22 to 24, and has a practically suitable level of foaming resistance.

The polyamide composition of example 16 is excellent in the evaluation of tensile breaking strength, heat distortion temperature and water absorption rate, and is equal to or more than those of comparative examples 22 to 24, and the polyamide composition of embodiment 4 is also excellent in mechanical properties, heat resistance and low water absorption rate.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. In contrast, the polyamide composition according to embodiment 4 has a specific structure in which the polyamide (a) contained therein has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus has further improved chemical resistance and further excellent various physical properties such as mechanical properties, heat resistance and low water absorption.

[ Polyamide composition of embodiment 5]

Next, the polyamide composition of embodiment 5 will be described more specifically with reference to examples and comparative examples, but the polyamide composition is not limited thereto.

Each evaluation in the production examples, examples and comparative examples was performed according to the method shown below.

Intrinsic viscosity

The intrinsic viscosity of the polyamides (samples) obtained in production examples 5-1 to 5-2 was determined in the same manner as in the above-described calculation method.

Melting point and glass transition temperature

The melting points and glass transition temperatures of the polyamides obtained in production examples 5-1 to 5-2 were determined in the same manner as in the above-described measurement methods.

Flame retardancy

The flame retardancy was evaluated in accordance with the specification of UL-94.

Using an injection molding machine (mold clamping force: 80 ton, screw diameter: φ 26mm) made by Hirtex resin Co., Ltd, the polyamide compositions obtained in example 17 and comparative examples 25 to 27 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of polyamide, and the polyamide compositions of example 17 and comparative example 25 were molded using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to obtain test pieces having a thickness of 0.4mm, a width of 13mm and a length of 125 mm.

Subsequently, the upper end of the obtained test piece was held by a holder and the test piece was vertically fixed, and a predetermined blue flame having a height of 20 ± 1mm was separated from the lower end of the test piece by being brought into contact with the lower end of the test piece for 10 seconds, and the combustion time of the test piece was measured (1 st time). Immediately after flame-out, the flame was again brought into contact with the lower end of the test piece and removed, and the burning time of the test piece was measured (2 nd time). The same measurement was repeated for 5 tablets to obtain 5 data of the 1 st combustion time and 5 data of the 2 nd combustion time, and 10 data were obtained in total. The total of 10 data is T, and the maximum of 10 data is M, and evaluation is performed according to the following evaluation criteria.

Further, it was visually confirmed whether or not the flame was dropped.

[ evaluation criteria ]

V-0: t is 50 seconds or less, M is 10 seconds or less, and the cotton does not burn to the holder and does not ignite 12 inches of cotton even if the melt with flame falls.

V-1: t is 250 seconds or less, M is 30 seconds or less, and the cotton does not burn to the holder and does not ignite under 12 inches even if the melt with flame falls.

V-2: t is below 250 seconds, M is below 30 seconds, there is no burning to the holder, and the melt with the flame falls to ignite the cotton at 12 inches.

X: none of the above evaluation criteria of UL94 is satisfied.

Resistance to foaming

Using an injection molding machine (mold clamping force: 18 ton, screw diameter: phi 18mm) manufactured by Sumitomo heavy machinery industry Co., Ltd.), the polyamide compositions obtained in example 17 and comparative examples 25 to 27 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the polyamide compositions of example 17 and comparative example 25 were molded (extrusion-molded) using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to prepare test pieces (sheets) having a length of 30mm, a width of 10mm and a thickness of 1 mm.

The obtained test piece was allowed to stand at 85 ℃ and 85% relative humidity for 168 hours. Thereafter, the test piece was subjected to a reflow test using an infrared heating furnace (SMT Scope, manufactured by shanyang seiki co., ltd.). In the reflux test, it took 60 seconds to heat up from 25 ℃ to 150 ℃, then 90 seconds to heat up to 180 ℃, and then 60 seconds to heat up to the peak temperature, and held at the peak temperature for 20 seconds. For the reflux test, the peak temperature was varied from 250 ℃ to 270 ℃ on a scale of 10 ℃. After the reflow test was completed, the appearance of the test piece was visually observed. The temperature at the limit where the test piece did not melt and no foaming occurred was defined as the foaming resistance temperature, and the case where the foaming resistance temperature exceeded 260 ℃ was defined as "o", the case where the foaming resistance temperature was 250 ℃ or more and 260 ℃ or less was defined as "Δ", and the case where the foaming resistance temperature was less than 250 ℃ was defined as "x", which was used as an index of the foaming resistance. The results were "O" and "Δ", and the results were found to be practically unproblematic levels.

Preparation of test piece 6

Using an injection molding machine (mold clamping force: 100 ton, screw diameter: 32mm) manufactured by Sumitomo heavy machinery industry Co., Ltd., the polyamide compositions obtained in example 17 and comparative examples 25 to 27 were set to a cylinder temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the polyamide compositions of example 17 and comparative example 25 were molded using a T-type casting mold under a mold temperature of 160 ℃ and under a mold temperature of 140 ℃ to prepare a multifunctional test piece A1 type (dumbbell type test piece described in JIS K7139; 4mm thick, 170mm in total length, 80mm in parallel portion length, and 10mm in parallel portion width).

Tensile breaking Strength

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 6 was used, and was obtained in the same manner as the above-described measurement method.

Heat distortion temperature

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 6 was used, and was obtained in the same manner as the above-described measurement method.

Water absorption

The multifunctional test piece A1 type (4mm thick) produced by the method for producing test piece 6 was used, and was obtained in the same manner as the above-described measurement method.

The respective ingredients used for preparing the polyamide compositions of examples and comparative examples are shown.

Polyamides (polyamides)

Production example 5-1

Production of semi-aromatic Polyamide (PA9N5-1)

9110.2g (42.14 moles) of 2, 6-naphthalenedicarboxylic acid, 6853.7g (43.30 moles) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 4/96 (molar ratio) ], 210.0g (1.72 moles) of benzoic acid, 16.2g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 8.3 liters of distilled water were placed in an autoclave containing 40 liters of an internal solvent, and nitrogen substitution was carried out. Stirring was carried out at 100 ℃ for 30 minutes, and it took 2 hours to raise the temperature inside the autoclave to 220 ℃. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued for 5 hours while maintaining the pressure at 2MPa, and the reaction was allowed to proceed by slowly withdrawing water vapor. Then, the pressure was reduced to 1.3MPa over 30 minutes, and the reaction was further carried out for 1 hour to obtain a prepolymer. The prepolymer thus obtained was dried at 100 ℃ under reduced pressure for 12 hours and then pulverized into a particle size of 2mm or less. This was subjected to solid-phase polymerization at 230 ℃ and 13Pa (0.1mmHg) for 10 hours to obtain a polyamide. The polyamide was abbreviated as "PA 9N 5-1".

Production example 5-2

Production of semi-aromatic Polyamide (PA9T5-1)

An autoclave having an internal volume of 40 liters was charged with 8190.7g (49.30 mol) of terephthalic acid, 7969.4g (50.35 mol) of a mixture of 1, 9-nonanediamine and 2-methyl-1, 8-octanediamine [ former/latter ] ═ 85/15 (mol ratio) ], 171.0g (1.40 mol) of benzoic acid, 16.3g (0.1 mass% based on the total mass of the raw materials) of sodium hypophosphite monohydrate, and 5.5 liters of distilled water, and then a polyamide was obtained in the same manner as in production example 5-1. The polyamide was abbreviated as "PA 9T 5-1".

Halogen-free element flame retardant

Halogen-free metal phosphinate flame retardant ("Exolit OP 1230" manufactured by Clariant Chemicals)

Filler (filler)

Glass fiber (1)

Glass fiber (CS-3J 256S manufactured by Ridong textile Co., Ltd.)

(average fiber diameter: 11 μm, average fiber length: 3mm, cross-sectional shape: circular)

Glass fiber (2)

Glass fiber (CSH 3PA870S manufactured by Nidong textile Co., Ltd.)

(3mm chopped strands, cross-sectional shape: cocoon type)

Other additives

Heat stabilizer (1)

Phosphorus heat stabilizer (Irgafos 168 from BASF corporation)

Heat stabilizer (2)

Hindered phenol heat stabilizer (Irganox 1098, product of BASF Co., Ltd.)

Heat stabilizer (3)

Phenol heat stabilizer ("SUMILIZER GA-80" manufactured by Sumitomo chemical Co., Ltd.)

Slip agent

Low molecular weight polyolefin slip agent ("HiWAX 200P" manufactured by Mitsui Kabushiki Kaisha)

Nucleating agents for crystals

Talc (TALC #5000S manufactured by Fuji TALC industries, Ltd.)

Example 17 and comparative examples 25 to 27

The components except for the filler were previously mixed at the ratio shown in table 8, and fed from a hopper at the upstream side of a twin-screw extruder ("BTN-32" by strain engineering) and the filler was fed from a side inlet at the downstream side of the extruder at the ratio shown in table 8. The melt-kneading is carried out at a hopper temperature 20 to 30 ℃ higher than the melting point of the polyamide, and the melt-kneaded product is extruded, cooled and cut to produce a granular polyamide composition.

The polyamide compositions obtained in example 17 and comparative examples 25 to 27 were used to evaluate the above-mentioned various physical properties. The results are shown in Table 8.

In Table 8, C9DA represents a1, 9-nonanediamine unit, and MC8DA represents a 2-methyl-1, 8-octanediamine unit.

[ Table 8]

As is clear from Table 8, the polyamide composition of example 17 is excellent in flame retardancy, has a small deformation amount in a combustion test, and has a foaming resistance equal to or higher than those of comparative examples 25 to 27. Further, since the flame retardant itself is halogen-free, the flame retardancy of the polyamide composition can be improved with a reduced environmental load.

The polyamide composition of example 17 is excellent in the evaluation of tensile breaking strength, heat distortion temperature and water absorption rate, and is equal to or more than those of comparative examples 25 to 27, and the polyamide composition of embodiment 5 is also excellent in mechanical properties, heat resistance and low water absorption.

As described in patent document 1, it is known that when an aliphatic diamine having a side chain is used, the crystallinity of the obtained polyamide is lowered, and it is not preferable in terms of heat resistance, chemical resistance, and the like. In contrast, the polyamide composition of embodiment 5 has a specific structure in which the polyamide (a) contained therein has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus has further improved chemical resistance and further has various excellent physical properties such as mechanical properties, heat resistance and low water absorption.