阅读说明：本技术 包含含有己内酰胺单体的特定共聚酰胺、半结晶聚酰胺和补强填充剂的具有增强的光泽性能的聚酰胺组合物 (Polyamide composition with enhanced gloss properties comprising a specific copolyamide containing caprolactam monomer, a semi-crystalline polyamide and a reinforcing filler ) 是由 M-K·林 F·斯佩罗尼 于 2018-12-20 设计创作，主要内容包括：提供了一种组合物,其包含a)至少一种包含己内酰胺单体或相应氨基酸、至少一种芳族二酸共聚单体和至少一种脂环族二胺共聚单体的共聚酰胺；b)至少一种半结晶聚酰胺；以及c)至少一种补强填充剂,其中a)至少一种共聚酰胺具有的结晶温度(Tc)为150℃或更低,且熔融温度(Tm)与Tc之差为50℃或更高。(A composition is provided comprising a) at least one copolyamide comprising caprolactam monomer or the corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer; b) at least one semi-crystalline polyamide; and c) at least one reinforcing filler, wherein a) the at least one copolyamide has a crystallization temperature (Tc) of 150 ℃ or less and a difference between the melting temperature (Tm) and Tc of 50 ℃ or more.)

1. A polyamide composition comprising

a) At least one copolyamide comprising a caprolactam monomer or corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer;

b) at least one semi-crystalline polyamide;

c) at least one reinforcing filler; and

d) at least one amorphous polyamide, at least one of which,

wherein a) at least one copolyamide has a crystallization temperature (Tc) of 150 ℃ or less and a difference between the melting temperature (Tm) and Tc of 50 ℃ or more.

2. The polyamide composition of claim 1, further comprising e) at least one flame retardant.

3. Polyamide composition according to claim 1 or 2, wherein a) at least one copolyamide comprises at least 75 mol% of caprolactam monomer or of the corresponding amino acid, based on the total number of moles of monomer and comonomer.

4. The polyamide composition of any one of claims 1 to 3, wherein b) at least one semi-crystalline polyamide is selected from the group consisting of polyamide 6, polyamide 6,10, polyamide 4,6, polyamide 11, polyamide 12, polyamide 6,12, copolyamide 6,6/6T, copolyamide 6,10/6T, copolyamide 6,12/6T, copolyamide 12/6T, copolyamide 6/6T, and any combination thereof.

5. Polyamide composition according to any one of claims 1 to 4, wherein c) at least one filler is chosen from glass fibers, glass beads, calcium carbonate, silicates, talc, kaolin, wollastonite, mica, wood flour, and also powders and fibers of other natural products and synthetic fibers, preferably glass fibers.

6. The polyamide composition according to any one of claims 1 to 5, wherein d) amorphous polyamide is selected from polyamide 6I/6T, polyamide 6I/10T, bis-4- (amino-3-methyl-cyclohexyl) -methane (3,3 '-dimethyl-4, 4' -diaminodicyclohexylmethane) (MACM), and mixtures and copolyamides thereof, preferably polyamide 6I/6T.

7. The polyamide composition according to any one of claims 1 to 6, further comprising f) at least one additive selected from the group consisting of colorants, lubricants, light stabilizers, heat stabilizers, plasticizers, nucleating agents, surfactants, antioxidants, antistatic agents, pigments, and any combination thereof.

8. Polyamide composition according to any one of claims 1 to 7, comprising a) at least one copolyamide in an amount of 2.0 to 30.0% by weight (wt%), preferably 3.0 to 20.0 wt%, more preferably 5.0 to 15.0 wt%, relative to the total weight of the composition.

9. Polyamide composition according to any one of claims 1 to 8, comprising b) at least one semi-crystalline polyamide in an amount ranging from 18.0 to 83.0% by weight, preferably from 40.0 to 77.0% by weight, more preferably from 50.0 to 70.0% by weight, relative to the total weight of the composition.

10. Polyamide composition according to any one of claims 1 to 9, comprising c) at least one reinforcing filler in an amount ranging from 15.0 to 70.0% by weight, preferably from 20.0 to 50.0% by weight, more preferably from 25.0 to 35.0% by weight, relative to the total weight of the composition.

11. Polyamide composition according to any one of claims 1 to 10, comprising d) at least one amorphous polyamide in an amount ranging from 3.0 to 20.0% by weight, preferably from 3.0 to 12.0% by weight, more preferably from 4.0 to 10.0% by weight, relative to the total weight of the composition.

12. Process for preparing a polyamide composition according to any one of claims 1 to 11, comprising melt blending a) at least one copolyamide, b) at least one semi-crystalline polyamide, and c) at least one reinforcing filler.

13. A molded part prepared by injection molding or extrusion of the composition of any one of claims 1 to 11.

14. Use of a molded part according to claim 13 for the preparation of a housing or housing part in the following applications: automotive applications, industrial machinery and appliances, preferably automotive rearview mirror chassis, trim parts, cell phone frames, engine trim covers, laptop computer frames, circuit breaker boxes for electrical and electronic equipment, electromagnetic switches, contactors and connectors.

15. A housing or housing component comprising the molded component of claim 13.

Technical Field

The present invention relates to a polyamide composition comprising a) at least one copolyamide comprising caprolactam monomer or the corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer; b) at least one semi-crystalline polyamide; and c) at least one reinforcing filler, optionally with d) at least one amorphous polyamide, wherein a) at least one copolyamide has a crystallization temperature (Tc) of 150 ℃ or less and a difference between the melting temperature (Tm) and Tc of 50 ℃ or more, and also to a process for preparing such polyamide composition.

The invention also relates to a process for preparing the polyamide composition of the invention, comprising melt blending a) at least one copolyamide, b) at least one semi-crystalline polyamide, and c) at least one reinforcing filler.

The invention also relates to the production of moulded parts by injection moulding or extrusion of the composition according to the invention.

Another aspect of the invention relates to the use of molded parts for the production of housings or housing parts in various applications, including automotive applications, industrial machinery, appliances, and electrical and electronic applications, preferably rear view mirror chassis of automobiles, aesthetic parts (aesthetical parts), cell phone frames, engine beauty covers (engine beauty covers), notebook computer frames, breaker boxes for electrical and electronic devices, electromagnetic switches, contactors and connectors, and also photovoltaic power transmission devices and electric vehicles, which require good surface properties, including excellent gloss, during their service life, and to the housings or housing parts.

Background

The following discussion of the prior art is provided to place the present invention within the appropriate technical scope and to provide a more thorough understanding of the advantages of the present invention. It will be understood, however, that any discussion of the prior art throughout the specification should not be considered as an express or implied admission that such prior art is widely known or forms part of the common general knowledge in the field.

Polyamides are one of the polymers that are often used as engineering plastics for a very wide range of applications. Polyamide compositions are of significant commercial interest and are commonly molded by injection molding or extrusion and can be used to make a variety of articles in a variety of applications, including automotive applications, industrial machinery, appliances, electrical and electronic applications, and the like.

In general, in order to use the polyamide compositions in the preparation of certain articles, fillers are generally added to ensure the mechanical properties of the product. However, due to the presence of fillers, polyamide compositions comprising fillers and products made therefrom generally exhibit unsatisfactory gloss properties and surface appearance, and it is therefore difficult to use such polyamide compositions for the manufacture of articles in certain applications where surface appearance is considered necessary to evaluate their value as a market product. Also, certain modifications, material fluctuations and many other situations in the manufacturing process may lead to differences in the gloss properties and surface appearance of the products to be manufactured, which often leads to complaints or even returns of the products after quality checks by the customer.

Specific applications requiring constant surface quality and particularly excellent gloss properties over the lifetime thereof, such as automotive applications, industrial machinery, appliances, and electrical and electronic applications, preferably rear-view mirror chassis of automobiles, beauty parts, cell phone frames, engine beauty covers, notebook computer frames, circuit breaker boxes for electrical and electronic equipment, electromagnetic switches, contactors, and connectors, including photovoltaic power transmission equipment and electric vehicles, require a polyamide composition that can ensure excellent gloss properties and surface appearance.

Therefore, there is a need in the art for a polymer composition that can exhibit excellent gloss properties to have a satisfactory surface appearance while maintaining mechanical properties.

Disclosure of Invention

It is therefore an object of the present invention to provide a polyamide composition which exhibits excellent gloss properties and a better surface appearance, while maintaining satisfactory mechanical properties.

The present invention relates to a composition comprising: a) at least one copolyamide comprising a caprolactam monomer or corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer; b) at least one semi-crystalline polyamide; c) at least one reinforcing filler, and d) at least one amorphous polyamide, wherein a) at least one copolyamide has a crystallization temperature (Tc) of 150 ℃ or less and a difference between the melting temperature (Tm) and Tc of 50 ℃ or more.

Indeed, the inventors have unexpectedly found that the presence of a specific copolyamide a), optionally in combination with d) an amorphous polyamide, makes it possible to exhibit excellent gloss properties.

One of the essential features of the present invention is that by incorporating this specific copolyamide according to the invention a) into a polyamide composition, optionally in combination with d) amorphous polyamide, excellent gloss properties are achieved while maintaining satisfactory mechanical properties, such as tensile/flexural modulus, tensile/flexural stress, impact strength, elongation at break, etc.

The International commission on Illumination (CIE) defines the term "gloss" as a phenomenon in which a brightly reflected light or image of a bright object is seen on a surface due to the directional reflectivity of the surface. In other words, gloss is an optical property of a surface that is characterized by its ability to reflect light in a specular manner.

However, since the perception of gloss by the human eye is subjective, i.e. not a physical feature, objective criteria for gloss measurement are required.

Objective assessment of gloss can be obtained by using different types of gloss meters according to various international standards, such as ISO 2813, DIN 67530, ASTM D523 and BS 3900part D5, which are used in the industry to control gloss quality to ensure consistency of the product during its preparation and during its service life.

A gloss meter is an instrument for measuring the specular gloss of a surface. Gloss is determined by projecting a beam of light at a fixed intensity and angle onto a surface and measuring the amount of reflected light at equal but opposite angles. In other words, a gloss meter is used to measure the gloss of the fraction of light (share) reflected from a surface in a direction complementary to the angle of incidence.

Thus, the gloss meter may provide a quantifiable way of measuring gloss, which may ensure consistency of gloss measurements by defining precise lighting and viewing conditions. The measurement angle refers to the angle between the incident light and the perpendicular, related to the amount of light reflected from a black glass standard with a defined refractive index. The ratio of reflected light to incident light of the sample was compared to the ratio of the gloss standard and recorded as gloss units ("GU"). Three measured angles (20 °, 60 ° and 85 °) were specified to cover most industrial paint applications.

In the present invention, the term "polyamide" is intended to denote in particular any recurring unit [ recurring unit (R) which comprises formula (I) or formula (II) ]_PA)]The polyamide (b):

formula (I): -NH-R¹-CO-，

Formula (II): -NH-R²-NH-CO-R³-CO-，

Wherein

-R¹Identical or different from each other at each occurrence, is a divalent hydrocarbon radical having from 1 to 17 carbon atoms;

-R²identical or different from each other at each occurrence, is a divalent hydrocarbon radical having from 1 to 18 carbon atoms; and

-R³identical or different from each other at each occurrence, is a divalent hydrocarbon radical having from 1 to 16 carbon atoms;

repeating unit (R) of polyamide_PA) In particular by polycondensation of (1) β -lactam, 5-aminopentanoic acid, -caprolactam, 9-aminononanoic acid, 10-aminodecanoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and/or (2) oxalic acid (HOOC-COOH), malonic acid (HOOC-CH)₂-COOH), succinic acid (HOOC- (CH)₂)₂-COOH), glutaric acid (HOOC- (CH)₂)₃-COOH), adipic acid (HOOC- (CH)₂)₄-COOH), 2,4, 4-trimethyladipic acid (HOOC-CH (CH)₃)-CH₂-C(CH₃)₂-CH₂-COOH), heptanediolAcid (HOOC- (CH)₂)_5-COOH), suberic acid (HOOC- (CH)₂)₆-COOH), azelaic acid (HOOC- (CH)₂)₇-COOH), sebacic acid (HOOC- (CH)₂)₈-COOH), undecanoic acid (HOOC- (CH)₂)₉-COOH), dodecanoic acid (HOOC- (CH)₂)₁₀-COOH), tetradecanoic acid (HOOC- (CH)₂)₁₂-COOH), octadecanoic acid (HOOC- (CH)₂)₁₆-COOH), terephthalic acid, isophthalic acid, 1, 8-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, 5-hydroxyisophthalic acid, 5-sulfoisophthalic acid, 5-aminoisophthalic acid and biphenyl-2, 2' -dicarboxylic acid, and at least one diamine selected from 1, 4-diamino-1, 1-dimethylbutane, 1, 4-diamino-1-ethylbutane, 1, 4-diamino-1, 2-dimethylbutane, 1, 4-diamino-1, 3-dimethylbutane, 1, 4-diamino-1, 4-dimethylbutane, 1, 4-diamino-2, 3-dimethylbutane, 1, 2-diamino-1-butylethane, 1, 6-diaminohexane, 1, 7-diaminoheptane, 1, 8-diamino-octane, 1, 6-diamino-2, 5-dimethylhexane, 1, 6-diamino-2, 4-dimethylhexane, 1, 6-diamino-3, 3-dimethylhexane, 1, 6-diamino-2, 2-dimethylhexane, 1, 9-diaminononane, 1, 6-diamino-2, 2, 4-trimethylhexane, 1, 6-diamino-2, 4, 4-trimethylhexane, 1, 7-diamino-2, 3-dimethylheptane, 1, 7-diamino-2, 4-dimethylheptane, 1, 7-diamino-2, 5-dimethylheptane, 1, 7-diamino-2, 2-dimethylheptane, 1, 10-diaminodecane, 1, 8-diamino-1, 3-dimethyloctane, 1, 8-diamino-1, 4-dimethyloctane, 1, 8-diamino-2, 4-dimethyloctane, 1, 8-diamino-3, 4-dimethyloctane, 1, 8-diamino-4, 5-dimethyloctane, 1, 8-diamino-2, 2-dimethyloctane, 1, 8-diamino-3, 3-dimethyloctane, 1, 8-diamino-4, 4-dimethyloctane, 1, 6-diamino-2, 4-diethylhexane, 1, 9-diamino-5-methylnonane, 1, 11-diaminoundecane, 1, 12-diaminododecane, isophoronediamine, bis (3, 5-dialkyl-4-aminocyclohexyl) methane, bis (3, 5-dialkyl-4-aminocyclohexyl) ethane, bis (3, 5-dialkyl-4-aminocyclohexyl) propane, bis (3, 5-dialkyl-4-aminocyclohexyl) butane, bis (3-methyl-4-aminocyclohexyl) methane, 4' -diaminodicyclohexylmethaneAn alkane, 4' -diamino-3, 3' -dimethyldicyclohexylmethane, 1, 2-diaminocyclohexane, 1, 4-diaminocyclohexane, 4-amino-2, 2,6, 6-tetramethylpiperidine, piperazine, N- (2-aminoethyl) piperazine and N, N ' -bis (2-aminoethyl) piperazine.

Exemplary repeating units (R) of polyamides_PA) In particular:

(i)-NH-(CH₂)₅-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of caprolactam;

(ii)-NH-(CH₂)₈-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of 9-aminononanoic acid;

(iii)-NH-(CH₂)₉-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of 10-aminodecanoic acid;

(iv)-NH-(CH₂)₁₀-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of 11-aminoundecanoic acid;

(v)-NH-(CH₂)₁₁-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of laurolactam;

(vi)-NH-(CH₂)₆-NH-CO-(CH₂)₄-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of hexamethylenediamine and adipic acid;

(vii)-NH-(CH₂)₆-NH-CO-(CH₂)₈-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of hexamethylenediamine and sebacic acid;

(viii)-NH-(CH₂)₆-NH-CO-(CH₂)₁₀-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of hexamethylenediamine and dodecanoic acid;

(ix)-NH-(CH₂)₁₀-NH-CO-(CH₂)₁₀-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of decamethylenediamine and dodecanoic acid;

(x)-NH-(CH₂)₆-NH-CO-(CH₂)₇-CO-, i.e. may be obtained by hexamethylenediamine andrecurring units obtained in particular by the polycondensation reaction of azelaic acid (azelaicic acid), also known as nonandioic acid;

(xi)-NH-(CH₂)₁₂-NH-CO-(CH₂)₁₀-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of dodecamethylenediamine and dodecanoic acid;

(xii)-NH-(CH₂)₁₀-NH-CO-(CH₂)₈-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of decamethylenediamine and capric acid;

(xiii)-NH-(CH₂)₄-NH-CO-(CH₂)₄-CO-, i.e. a recurring unit which can be obtained in particular by polycondensation of 1, 4-butanediamine and adipic acid; and

(xiv)-NH-(CH₂)₄-NH-CO-(CH₂)₈-CO-, i.e. a recurring unit which can be obtained in particular by the polycondensation reaction of 1, 4-butanediamine and sebacic acid.

Preferably, as mentioned above, the polyamide consists essentially of recurring units (R)_PA) Composition, it is understood that end chains, defects and other irregularities may be present in the polyamide chain without affecting its properties.

Repeating unit (R) of polyamide_PA) May all be of the same type or may be of more than one type, that is to say the Polyamide (PA) may be a homopolyamide or a copolyamide.

In the present invention, the term "copolyamide comprising caprolactam monomer or the corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer" is intended to denote in particular a copolyamide obtained by polymerization of caprolactam or the corresponding amino acid as main monomer, with at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer. The aromatic diacid comonomer is capable of forming an amine-functional amide linkage with the cycloaliphatic diamine comonomer and is capable of forming a copolyamide by covalently bonding the amide linkage with the main monomer of the copolyamide. The amine function of the cycloaliphatic diamine comonomer is preferably a primary amine function or a salt thereof.

The aromatic diacid comonomers of the present invention are comonomers comprising at least one aromatic ring and at least two carboxylic acids. The aromatic diacid comonomer preferably contains 6 to 20 carbon atoms.

Examples of aromatic diacid comonomers include terephthalic acid, isophthalic acid, 1, 8-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, 5-hydroxyisophthalic acid, 5-sulfoisophthalic acid, 5-aminoisophthalic acid, and biphenyl-2, 2' -dicarboxylic acid.

The cycloaliphatic diamine comonomers of the present invention are comonomers comprising at least one aliphatic ring and at least two amines. The cycloaliphatic diamine comonomer preferably contains from 4 to 20 carbon atoms.

Examples of alicyclic diamine comonomers include isophoronediamine, bis (3, 5-dialkyl-4-aminocyclohexyl) methane, bis (3, 5-dialkyl-4-aminocyclohexyl) ethane, bis (3, 5-dialkyl-4-aminocyclohexyl) propane, bis (3, 5-dialkyl-4-aminocyclohexyl) butane, bis (3-methyl-4-aminocyclohexyl) methane, 4' -diaminodicyclohexylmethane, 4' -diamino-3, 3' -dimethyldicyclohexylmethane, 1, 2-diaminocyclohexane, 1, 4-diaminocyclohexane, 4-amino-2, 2,6, 6-tetramethylpiperidine, piperazine, N- (2-aminoethyl) piperazine, and N, N' -bis (2-aminoethyl) piperazine.

The copolyamides of the invention can be prepared by conventional polymerization processes, in particular by continuous or batchwise polymerization processes.

Examples of copolyamides of the present invention include but are not limited to,

copolyamides 6 comprising as comonomer a mixture of terephthalic acid and isophoronediamine and

copolyamide 6 comprising as comonomers a mixture of isophthalic acid and isophoronediamine.

In a particular embodiment of the invention, the amount of a) at least one copolyamide comprising caprolactam monomer or the corresponding amino acid, at least one aromatic diacid comonomer and at least one cycloaliphatic diamine comonomer is from 2.0% to 30.0% by weight, preferably from 3.0% to 20.0% by weight, more preferably from 5.0% to 15.0% by weight, relative to the total weight of the composition.

In a particular embodiment of the invention, the amount of caprolactam monomer or corresponding amino acid in the a) at least one copolyamide is at least 75 mol%, preferably at least 85 mol%, more preferably at least 90 mol%, most preferably at least 95 mol%, based on the total number of moles of monomer and comonomer.

In a particular embodiment of the invention, the amount of the mixture of aromatic diacid comonomer and cycloaliphatic diamine comonomer in the a) at least one copolyamide is 25 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, most preferably 5 mol% or less, based on the total number of moles of monomer and comonomer.

In the present invention, the term "semi-crystalline polyamide" is intended to denote in particular a polyamide comprising crystallizable and amorphous portions in the skeleton, i.e. an amorphous polymeric material comprising randomly entangled chains, while a crystalline material comprises regions of polymer chains arranged in an ordered array, wherein these crystalline regions are embedded in an amorphous polymeric matrix. The semi-crystalline polyamide of the invention has a melting point of greater than 150 ℃ and a heat of fusion of greater than 5J/g. The melting point can be measured by any known method, such as Differential Scanning Calorimetry (DSC).

Examples of b) at least one semi-crystalline polyamide suitable for use in the present invention include, but are not limited to, polyamide 6, polyamide 6,10, polyamide 4,6, polyamide 11, polyamide 12, polyamide 6,12, copolyamide 6,6/6T, copolyamide 6,10/6T, copolyamide 6,12/6T, copolyamide 12/6T, copolyamide 6/6T, and any combination thereof.

Particularly preferred semi-crystalline polyamides for use in the composition of the present invention are polyamide 6,6 and copolyamide 6, 6/6T.

A particularly preferred semi-crystalline polyamide for use in the composition of the invention is copolyamide 6,6/6T having a molar ratio of polyamide 6,6 to polyamide 6T of 4:1 to 1:1, preferably about 2: 1.

One or more semi-crystalline polyamides may be used in the composition. Thus, according to certain embodiments, mixtures of semi-crystalline polyamides may be used.

In a particular embodiment of the invention, the amount of b) at least one semi-crystalline polyamide ranges from 15% to 83.0% by weight, relative to the total weight of the composition. Preferably, the amount of the at least one semi-crystalline polyamide may be from 18.0% to 77.0% by weight, more preferably from 30.0% to 55.0% by weight, relative to the total weight of the composition.

In the present invention, the term "reinforcing filler" is intended to denote in particular a material added to the polymer composition to improve its properties and/or to reduce costs. By appropriate selection of these materials, not only economy, but also other properties, such as processing and mechanical properties, can be improved. While these reinforcing fillers retain their inherent characteristics, very significant differences are often seen depending on molecular weight, mixing techniques and the presence of other additives in the formulation. Thus, once the basic performance requirements are established, the optimum type and loading level of filler (loading level) must be determined to balance cost and performance.

In the present invention, the filler is preferably selected from glass fibers, glass beads, calcium carbonate, silicates, talc, kaolin, wollastonite, mica, wood flour, powders and fibers of other natural products, and synthetic fibers. Glass fibers are most advantageously used in the compositions of the present invention.

In a particular embodiment of the invention, the amount of c) at least one reinforcing filler ranges from 15.0 to 70.0% by weight, preferably from 20.0 to 55.0% by weight, relative to the total weight of the composition.

The composition of the invention may optionally comprise d) at least one amorphous polyamide. In the context of the present invention, the term "amorphous polyamide" is intended to mean in particular a polyamide having a heat of fusion of less than 5J/g, preferably 0J/g, i.e.having no detectable melting point, and having a high degree of resistance to e.g.O₂And CO₂The polyamide exhibits excellent transparency and good barrier properties. Amorphous polyamides hinder the crystallization rate and thus lead to excellent surface appearance. Examples of amorphous polyamides suitable for use in the present invention include, but are not limited to, polyamide 6I/6T, polyimidesAmine 6I/10T, bis-4- (amino-3-methyl-cyclohexyl) -methane (3,3 '-dimethyl-4, 4' -diaminodicyclohexylmethane) (MACM), and mixtures and copolyamides thereof, preferably polyamide 6I/6T. Polyamide 6I/6T, which can be prepared by copolymerization of 1, 6-hexamethylenediamine, isophthalic acid and terephthalic acid, is most advantageously used in the composition according to the invention. Can be combined withPolyamide 6I/6T is a suitable commercially available amorphous polyamide which may be used in the compositions of the present invention.

In the present invention, the amount of d) at least one amorphous polyamide may be up to 20.0 weight% (wt%), such as from 0.1 to 20 wt%, preferably up to 15.0 wt%, such as from 0.5 to 15 wt%, more preferably up to 12.0 wt%, such as from 1 to 12 wt%, most preferably up to 10.0 wt%, such as from 1 to 10 wt%, relative to the total weight of the composition. In a preferred embodiment, the weight concentration of d) at least one amorphous polyamide ranges from 3.0 to 20.0% by weight, preferably from 3.0 to 12.0% by weight, more preferably from 4.0% by weight to 10.0% by weight, relative to the total weight of the composition.

The compositions of the invention may optionally comprise e) at least one flame retardant, which is generally used in the field of polyamides. In the present invention, the term "flame retardant" is intended to denote in particular compounds that are well known to the person skilled in the art, capable of reducing the propagation of flames and/or having flame retardant properties. These flame retardants are commonly used in flame retardant compositions. Advantageously, the composition comprises at least one flame retardant selected from:

phosphorus-containing flame retardants, such as:

phosphine oxides such as triphenylphosphine oxide, tris (3-hydroxypropyl) phosphine oxide and tris (3-hydroxy-2-methylpropyl) phosphine oxide;

phosphonic acid or salts thereof or phosphinic acid or salts thereof, for example zinc, magnesium, calcium, aluminum or manganese salts of phosphinic acid, in particular aluminum salts of diethylphosphinic acid or zinc salts of dimethylphosphinic acid;

cyclic phosphonates such as cyclic diphosphates, for example Antiblaze 1045;

phosphates such as triphenyl phosphate, ammonium polyphosphate, melamine polyphosphate and sodium polyphosphate;

red phosphorus, for example in powder form or in the form of a masterbatch, in stabilized or coated form;

flame retardants of the organonitrogen type, for example triazines, cyanuric and/or isocyanuric acid, melamine or derivatives thereof, such as melamine cyanurate, melamine oxalate, phthalates, borates, sulfates, phosphates, polyphosphates and/or pyrophosphates, condensed melamine products, such as melem, melam and melon, tris (hydroxyethyl) isocyanurate, benzoguanamine, guanidine, allantoin and glycoluril;

flame retardants containing halogenated derivatives, such as:

bromine derivatives, such as PBDPOs (polybromodiphenyl ether), BrPS (polybromostyrene and brominated polystyrene), poly (pentabromobenzylacrylate), indene bromide, tetradecylbenzoyloxybenzene (Saytex 120), 1, 2-bis (pentabromophenyl) ethane or Saytex 8010 from Albemarle, tetrabromobisphenol a and brominated epoxy oligomers. Among the brominated derivatives are, in particular, polydibromostyrenes such as PDBS-80 from Chemtura, brominated polystyrenes such as Saytex HP 3010 from Albemarle or FR-803P, decabromodiphenyl ether (DBPE) or FR-1210 from Dead Sea Bromine Group, octabromodiphenyl ether (OBPE), 2,4, 6-tris (2,4, 6-tribromophenoxy) -1,3, 5-triazine or FR-245 from Dead Sea Bromine Group, poly (pentabromobenzyl acrylate) or FR-1025 from Dead Sea Bromine Group, and epoxy-terminated oligomers or polymers of tetrabromobisphenol A, such as F-2300 and F2400 from Dead Sea Bromine Group.

Chlorinated compounds, e.g. chlorinated alicyclic compounds, e.g. Dechlorane

(sold by OxyChem, see CAS 13560-89-9).

These compounds may be used alone or in combination, sometimes in a synergistic manner. Particular preference is given to synergistic combinations of phosphorus-containing compounds, such as phosphine oxides, phosphonic acids or salts thereof or phosphinic acids or salts thereof, and also cyclic phosphonic acid esters with nitrogen-containing derivatives, such as melam, melem, melamine phosphate, melamine polyphosphate or ammonium polyphosphate.

It is particularly preferred that the composition of the invention comprises compound F1 of the formula:

[R¹R²P(＝O)-O]_z ^-M^z+

wherein:

-R¹and R²Identical or different, represent a linear or branched alkyl group comprising from 1 to 6 carbon atoms, and preferably from 1 to 3 carbon atoms and/or an aryl group;

-M represents calcium, magnesium, aluminium and/or zinc ions, preferably magnesium and/or aluminium ions;

-Z represents 2 or 3, preferably 3.

The composition of the invention may also comprise compound F2, which is the reaction product of phosphoric acid and melamine and/or the reaction product of phosphoric acid and a condensed melamine product.

The compositions of the invention may also comprise compounds F1 and F2.

Such a fire-retardant system is described in particular in patent US 6,255,371. The composition may comprise from 1.0 to 70.0 wt%, preferably from 5.0 to 40.0 wt%, even more preferably from 10.0 to 30.0 wt%, and in particular from 15.0 to 30.0 wt% of the flame retardant system, relative to the total weight of the composition. Preferably, the weight ratio of each of compounds F1 and F2 is from 1:1 to 4:1, preferably about 3: 2.

R¹And R²Which may be identical or different, represent methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl and/or aryl, for example phenyl. M is preferably an aluminum ion. The phosphinic acid of compound F1 can be selected, for example, from dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid and methyl-n-propylphosphinic acid, or mixtures thereof. Various phosphonic acids may be used in combination.

The phosphinic acid salts according to the invention can be prepared according to conventional methods which are well known to the person skilled in the art, for example as described in patent EP 0699708. The phosphinic acid salts of the present invention may be used in various forms depending on the nature of the polymer and the desired properties. For example, the phosphinate may be in the form of fine particles in order to obtain good dispersibility in the polymer.

Compound F2 is the reaction product of phosphoric acid and melamine and/or the reaction product of phosphoric acid and a condensed melamine product. Various compounds F2 can be used in combination. The condensed melamine products are, for example, melam, melem and melon. Even more condensation compounds may be used. Preferably, compound F2 may be selected, for example, from the following reaction products: melamine polyphosphate, melam polyphosphate and melem polyphosphate or mixtures thereof. Particular preference is given to using chains which contain melamine polyphosphate and whose length is greater than 2, in particular greater than 10.

These compounds are described in particular in patent WO 98/39306. Compound F2 can also be obtained via methods other than those based on direct reaction with phosphoric acid. For example, melamine polyphosphate may be prepared by the reaction of melamine with polyphosphoric acid (see WO 98/45364) or by condensation of melamine phosphate and condensation of melamine pyrophosphate (see WO 98/08898).

In a completely preferred manner, the flame-retardant system of the invention comprises a compound F1, in which R¹＝R²Ethyl, M-aluminum and Z-3; and compound F2: melamine polyphosphate. The weight ratio of each of compounds F1 and F2 may be 3: 2.

Other compounds which participate in flame retardancy, such as zinc borate, zinc oxide and magnesium hydroxide, may also be added to the formulation.

In the present invention, the amount of e) at least one flame retardant may be from 0 to 30.0 wt.%, preferably from 0 to 25.0 wt.%, and more preferably from 0 to 20.0 wt.%, relative to the total weight of the composition. If included in the composition of the invention, the concentration by weight of e) at least one flame retardant may range from 5.0 to 30.0% by weight, preferably from 7.0 to 25.0% by weight, relative to the total weight of the composition.

In addition, the composition of the present invention may optionally comprise f) at least one additive. Examples of additives that may be advantageously used include, but are not limited to, colorants, lubricants, light stabilizers, heat stabilizers, plasticizers, nucleating agents, surfactants, antioxidants, antistatic agents, pigments, and the like.

In the present invention, the amount of f) at least one additive may be from 0 to 5.0% by weight, preferably from 0 to 4.0% by weight, relative to the total weight of the composition. If included in the composition of the present invention, the weight concentration of the additive may range from 0.2 to 4.0% by weight, preferably from 1.0 to 3.5% by weight, relative to the total weight of the composition.

The invention also relates to a process for preparing the polyamide composition of the invention, comprising melt blending a) at least one copolyamide, b) at least one semi-crystalline polyamide, and c) at least one reinforcing filler. The compositions of the invention can be used as starting materials, for example for the preparation of articles by injection moulding, by injection/blow moulding, by extrusion or by extrusion/blow moulding, preferably by injection moulding. According to an embodiment, the polyamide composition is extruded in the form of strands, for example in a twin-screw extruder, and then cut into pellets. The molded part is then prepared by melting the pellets and feeding the molten composition to an injection molding apparatus.

Another aspect of the present invention relates to molded parts prepared by injection molding of the compositions of the present invention.

Another aspect of the invention relates to the use of a molded part for the preparation of housings or housing parts in various applications, including automotive applications, industrial machinery, appliances, preferably rear view mirror chassis and trim parts for automobiles, cell phone frames, motor trim covers, notebook computer frames, or electrical and electronic applications such as circuit breaker boxes, electromagnetic switches, contactors and connectors for electrical and electronic equipment, and also including photovoltaic power transmission equipment and electric vehicles, which require good surface properties (including excellent gloss) during their service life, and to the housings or housing parts.

Further details or advantages of the invention will become apparent from the examples given below. The invention will be illustrated by the following examples, which are intended to illustrate, but not to limit the invention.

Examples