阅读说明：本技术 一种星型聚酰胺及其用途 (Star polyamide and application thereof ) 是由 徐伟箭 苏建海 欧恩才 王仲霞 雷智友 杨海青 于 2019-10-16 设计创作，主要内容包括：本发明涉及一种星型聚酰胺及其用途,将二酸酐作为引发剂或酰胺交换剂加入到聚酰胺的聚合过程,通过引发单体聚合或酰胺交换,得到星型聚酰胺,二酸酐的加入量为聚合单体重量的0.5～10%。星型聚酰胺的用途是制备荧光材料、聚酰胺改性剂或碳材料增溶剂。聚酰胺改性剂作为润滑剂,降低聚酰胺黏度,使聚酰胺具有较高的流动性。碳材料增溶剂改善了碳材料与聚酰胺基体界面的相容性。本发明在加入二酸酐作引发剂或酰胺交换剂,通过引发单体聚合或酰胺交换,得到星型聚酰胺,改善了聚酰胺的性能,制备出性能优异的复合材料,扩大了聚酰胺产品的用途。(The invention relates to star polyamide and application thereof, wherein dianhydride is used as an initiator or an amide exchanger and is added into the polymerization process of polyamide, and the star polyamide is obtained by initiating monomer polymerization or amide exchange, wherein the addition amount of dianhydride is 0.5-10% of the weight of a polymerization monomer. The star polyamide is used for preparing fluorescent materials, polyamide modifiers or carbon material solubilizers. The polyamide modifier is used as a lubricant to reduce the viscosity of the polyamide and enable the polyamide to have higher fluidity. The carbon material solubilizer improves the compatibility of the carbon material with the polyamide matrix interface. In the invention, dianhydride is added as an initiator or an amide exchanger, and the star polyamide is obtained by initiating monomer polymerization or amide exchange, so that the performance of the polyamide is improved, the composite material with excellent performance is prepared, and the application of the polyamide product is expanded.)

1. A star polyamide, characterized by: adding dianhydride serving as an initiator or an amide exchanger into a polyamide polymerization process, and initiating monomer polymerization or amide exchange to obtain star polyamide, wherein the addition amount of the dianhydride is 0.5-10% of the weight of a polymerization monomer; the preparation method of the star polyamide comprises the following steps:

adding dianhydride into an organic solvent, and ultrasonically dispersing for 1-2 hours at 60-80 ℃ to obtain a dianhydride solution;

the method comprises the following steps of adding a dianhydride solution obtained in the step into a reaction system for preparing polyamide, wherein the dianhydride solution is added in the early stage of polymerization, added in the middle stage of polymerization or added in the later stage of polymerization, and reacting for 3-5 hours at 140-160 ℃ to obtain star polyamide.

2. The star polyamide as claimed in claim 1, wherein: the organic solvent is DMSO; the mass concentration of the dianhydride solution is 10-60 mg/mL; the polymerization method is polycondensation or anionic polymerization.

3. The star polyamide as claimed in claim 1, wherein: the polyamide is polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 46, polyamide 1010, poly (p-phenylene terephthalamide), poly (p-phenylene isophthalamide) or poly (hexamethylene terephthalamide) and copolymers thereof.

4. The star polyamide as claimed in claim 1, wherein: the monomer of the polyamide is caprolactam, adipic acid, hexamethylene diamine, sebacic acid, decamethylene diamine, 1, 4-butanediamine, terephthalic acid or p-xylylenediamine.

5. The star polyamide as claimed in claim 1, wherein: the dianhydride is pyromellitic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, perylene-3, 4,9, 10-tetracarboxylic dianhydride, 3',4,4' -benzophenone tetracarboxylic dianhydride, hexafluoroisopropyl phthalic anhydride, 3',4,4' -biphenyl tetracarboxylic dianhydride, 3',4,4' -diphenyl sulfone tetracarboxylic dianhydride or 4,4' -oxydiphthalic anhydride.

6. Use of the star polyamide according to claim 1, characterized in that: the star polyamide is used for preparing a fluorescent material, a polyamide modifier and a carbon material solubilizer; the polyamide modifier is used as a lubricant to reduce the viscosity of the polyamide and ensure that the polyamide has higher fluidity; the carbon material solubilizer improves the compatibility of the carbon material with the polyamide matrix interface.

7. Use of the star polyamide according to claim 6, characterized in that: the application method of the polyamide modifier comprises the following steps: the star polyamide and the polyamide are blended by a double-screw extruder according to the weight ratio of 30-50% to 50-70%, the extrusion temperature is 230-260 ℃, and then the polyamide modifier is obtained through granulation by a granulator.

8. Use of the star polyamide according to claim 7, characterized in that: the preparation method of the fluorescent material comprises the following steps: adding an auxiliary agent into a polyamide modifier and a glass fiber according to a weight ratio of 60-80% to 20-40%, blending by using a double-screw extruder at an extrusion temperature of 230-260 ℃, and then granulating by using a granulator to obtain a glass fiber/polyamide material; the auxiliary agent is a coupling agent KH550, and the dosage of the auxiliary agent is 2-8% of the weight of the glass fiber.

9. Use of the star polyamide according to claim 6, characterized in that: the preparation method of the carbon material solubilizer comprises the following steps: the star polyamide, the polyamide and the carbon material are blended by a double-screw extruder according to the weight ratio of 5-10% to 50-75% to 20-40%, the extrusion temperature is 230-260 ℃, and then the mixture is granulated by a granulator to obtain the carbon material/polyamide composite material.

10. The star polyamide as claimed in claim 9, wherein: the carbon material is fullerene, carbon nano tube, graphene, carbon black, graphene oxide, graphite ore powder or coal gangue powder.

Technical Field

The invention belongs to the technical field of polymer composite materials, and relates to star polyamide and application thereof.

Background

Since the last 30 s, polyamide was developed by dupont, and has excellent electrical and mechanical properties, and good solvent resistance, wear resistance, self-lubrication, and processing and forming properties, it is widely used in many fields such as automobiles, electronics, construction, machinery, and energy. Polyamides play an increasingly important role in saving energy, replacing metals, and the like. As one of five engineering plastics, the plastic plays a very important role in economic development.

However, in order to apply the polyamide to more prominent positions, it needs to be further subjected to reinforcing and toughening modification. The problem to be solved mainly by the reinforcing and toughening modification is the interface compatibility. In the past, the polyamide is subjected to enhanced modification, and coupling agents such as silane coupling agents, titanate coupling agents and aluminate coupling agents are mainly added to improve interface compatibility. The toughening modification is mainly added with a solubilizer, such as maleic anhydride grafted ABS and maleic anhydride grafted SEBS. The principles of the two methods are similar, and the added auxiliary agents are polar groups which contain hydroxyl, carboxyl, epoxy and the like at one end and can chemically react with polyamide, and the other end can be compatible with filling materials or other resins, so that the compatibility of the interface is obviously improved.

The polyamide modified by the materials such as glass fiber, carbon fiber, graphite ore, carbon black and the like makes an important breakthrough in the aspects of increasing the strength of the composite material and reducing the cost. However, as these inorganic fillers are increased, the processability of the composite material is also decreased. If high-fluidity star polyamide can be added in the modification process, the mechanical processing performance of the star polyamide is greatly modified, the cost is further reduced, and the strength of the composite material is increased.

Disclosure of Invention

The invention aims to provide the star polyamide, improve the performance of the polyamide, prepare a composite material with excellent performance and expand the application of polyamide products. Another object of the present invention is to provide the use for the preparation of fluorescent materials, polyamide modifiers and carbon material solubilisers.

The technical scheme of the invention is that dianhydride is added into polyamide polymerization process as an initiator or an amide exchanger to obtain star polyamide by initiating monomer polymerization or amide exchange, wherein the addition amount of dianhydride is 0.5-10% of the weight of the polymerization monomer. The preparation method of the star polyamide comprises the following steps:

adding dianhydride into an organic solvent, and ultrasonically mixing for 1-2 hours at 60-80 ℃ to obtain a dianhydride solution;

the method comprises the following steps of adding the dianhydride solution obtained in the step into a reaction system for preparing polyamide, wherein the adding mode is adding in the early stage of polymerization, adding in the middle stage of polymerization or adding in the later stage of polymerization, and reacting for 3-5 hours at 140-160 ℃ to obtain star polyamide. The structural formula of the star polyamide is as follows:

the organic solvent is dimethyl sulfoxide (DMSO), and the mass concentration of the dianhydride solution is 10-60 mg/mL. The polymerization method is polycondensation or anionic polymerization.

The polyamide is polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 46, polyamide 1010, poly (p-phenylene terephthalamide), poly (p-phenylene isophthalamide) or poly (hexamethylene terephthalamide), and copolymers thereof.

The polyamide monomer is caprolactam, adipic acid, hexamethylene diamine, sebacic acid, decamethylene diamine, 1, 4-butylene diamine, terephthalic acid or p-xylylenediamine. The dianhydride is pyromellitic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, perylene-3, 4,9, 10-tetracarboxylic dianhydride, 3',4,4' -benzophenone tetracarboxylic dianhydride, hexafluoroisopropyl phthalic anhydride, 3',4,4' -biphenyl tetracarboxylic dianhydride, 3',4,4' -diphenyl sulfone tetracarboxylic dianhydride or 4,4' -oxydiphthalic anhydride. The structural formula of the compound is as follows:

pyromellitic dianhydride:；

1,4,5, 8-naphthalene tetracarboxylic acid dianhydride:；

perylene-3, 4,9, 10-tetracarboxylic acid dianhydride:；

3,3',4,4' -benzophenone tetracarboxylic dianhydride:；

hexafluoroisopropylphthalic anhydride:；

3,3',4,4' -biphenyltetracarboxylic dianhydride:；

3,3',4,4' -diphenylsulfone tetracarboxylic dianhydride:and

4,4' -oxydiphthalic anhydride:。

the star polyamide is used for preparing a fluorescent material (glass fiber/polyamide material), a polyamide modifier and a carbon material solubilizer. The polyamide modifier is used as a lubricant to reduce the viscosity of the polyamide and ensure that the polyamide has higher fluidity. The carbon material solubilizer improves the compatibility of the carbon material with the polyamide matrix interface.

The preparation method of the polyamide modifier comprises the following steps: the star polyamide and the polyamide are blended by a double-screw extruder according to the weight ratio of 30-50% to 50-70%, and then are granulated by a granulator to obtain the polyamide modifier. The preparation method of the fluorescent material comprises the following steps: adding an auxiliary agent into the prepared polyamide modifier and the glass fiber according to the weight ratio of 60-80% to 20-40%, blending by using a double-screw extruder at the extrusion temperature of 230-260 ℃, and then granulating by using a granulator to obtain the glass fiber/polyamide material. The auxiliary agent is a coupling agent KH550, and the dosage of the auxiliary agent is 2-8% of the weight of the glass fiber. The preparation method of the carbon material solubilizer comprises the following steps: the star polyamide, the polyamide and the carbon material are blended by a double-screw extruder according to the weight ratio of 5-10% to 50-75% to 20-40%, the extrusion temperature is 230-. The carbon material is fullerene, carbon nano tube, graphene, carbon black, graphene oxide, graphite ore powder or coal gangue powder.

The star polyamide is prepared by adding single dianhydride or a mixture thereof in the early stage, the middle stage or the later stage of polymerization by adopting a polycondensation or anionic polymerization method. The star polyamide and the corresponding polyamide and carbon materials such as glass fiber and graphene are blended according to a certain proportion by adopting a melt blending extrusion mode to prepare the glass fiber/polyamide composite material and the carbon material/polyamide composite material with excellent performance.

In the invention, dianhydride is added as an initiator or an amide exchanger at the early stage, the middle stage or the later stage of the polyamide polymerization process, and the star polyamide is obtained by initiating the polymerization or amide exchange of monomers, so that the performance of the polyamide is improved, and the composite material with excellent performance is prepared. The fluorescent material, the polyamide modifier or the carbon material prepared from the star polyamide has good performance, and the application of the polyamide product is expanded.

Drawings

FIG. 1 is a diagram showing the appearance of the fluorescence of star-shaped polyamide under 365nm light irradiation;

FIG. 2 is an appearance diagram of the fluorescence of star-shaped polyamide without 365nm light irradiation;

FIG. 3 is a fluorescent spectrum of star polyamide;

FIG. 4 is a graph showing the appearance of the fluorescence of perylene anhydride/polyamide 6 star polymer under 365nm light irradiation;

FIG. 5 is a graph showing the appearance of the fluorescence of perylene anhydride/polyamide 6 star polymer in the absence of 365nm light.

Detailed Description

The present invention will be described in detail with reference to the following examples and drawings. The scope of protection of the invention is not limited to the embodiments, and any modification made by those skilled in the art within the scope defined by the claims also falls within the scope of protection of the invention.

Example 1:

adding 1,4,5, 8-naphthalene tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 2 hours at 70 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 20 mg/mL;

the dianhydride solution obtained in the step is added into a polymerization reactor of polyamide 6 in the early stage of polymerization, namely before the polymerization reaction is started, and the addition amount is 2% of the weight of the raw materials of the polymerization monomers. Reacting for 3 h at the temperature of 150 +/-5 ℃ to obtain star polyamide 6;

blending the star polyamide 6 and the polyamide 6 obtained in the step II according to the weight ratio of 30% to 70% by using a double-screw extruder, wherein the extrusion temperature is 230 ℃, and then granulating by using a granulator to obtain the polyamide modifier, namely the high-fluidity polyamide material;

fourthly, adding an auxiliary agent into the high-fluidity polyamide material obtained in the step three and the glass fiber according to the weight ratio of 60% to 40%, blending by using a double-screw extruder at the extrusion temperature of 260 ℃, and then granulating by using a granulator to obtain the glass fiber/polyamide material; the auxiliary agent is a coupling agent KH550, and the dosage of the auxiliary agent is 8% of the weight of the glass fiber.

Example 2

Adding perylene-3, 4,9, 10-tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 1.5h at 75 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 30 mg/mL;

adding adipic acid and hexamethylenediamine into a reaction kettle, and polymerizing through a polycondensation mechanism, wherein the dianhydride solution obtained in the step is added into a polymerization reactor of polyamide 66 in the middle stage of polymerization, namely 2h after the polymerization reaction begins, and the addition amount is 5% of the weight of the raw materials of the polymerization monomers. Reacting for 4 hours at the temperature of 145 +/-5 ℃ to obtain star polyamide 66;

blending the star polyamide 66 and the polyamide 66 obtained in the step II according to the weight ratio of 40% to 60% by using a double-screw extruder, wherein the extrusion temperature is 240 ℃, and then granulating by using a granulator to obtain a polyamide modifier, namely the high-fluidity polyamide material;

fourthly, adding an auxiliary agent into the high-fluidity polyamide material obtained in the step three and the glass fiber according to the weight ratio of 70% to 30%, blending by using a double-screw extruder at the extrusion temperature of 260 ℃, and then granulating by using a granulator to obtain the glass fiber/polyamide material; the auxiliary agent is a coupling agent KH550, and the dosage of the auxiliary agent is 5% of the weight of the glass fiber.

Example 3

Adding 3,3',4,4' -benzophenone tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 1.5 hours at 75 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 40 mg/mL;

adding adipic acid and decamethylene diamine into a reaction kettle, polymerizing by an anionic polymerization mechanism, and adding the dianhydride solution obtained in the step into a polymerization reactor of poly (p-phenylene terephthalamide) in the later polymerization stage, namely adding the dianhydride solution when the polymerization reaction is about to end, wherein the addition amount is 8% of the weight of the raw materials of the polymerization monomers. Reacting for 5h at the temperature of 155 +/-5 ℃ to obtain star polyamide 610;

blending the star polyamide 610 and the polyamide 610 obtained in the step II according to the weight ratio of 50% to 50% by using a double-screw extruder, wherein the extrusion temperature is 240 ℃, and then granulating by using a granulator to obtain a polyamide modifier, namely the high-fluidity polyamide material;

fourthly, adding an auxiliary agent into the high-fluidity polyamide material obtained in the step three and the glass fiber according to the weight ratio of 80% to 20%, blending by using a double-screw extruder at the extrusion temperature of 260 ℃, and then granulating by using a granulator to obtain the glass fiber/polyamide material; the auxiliary agent is a coupling agent KH550, and the dosage of the auxiliary agent is 2% of the weight of the glass fiber.

The melt index of the high-flow polyamide materials prepared in examples 1 to 3 was measured according to the international standard ISO 1133, and the results are shown in table 1, and the results of the tests of the polyamides PA6, PA66 and PA610 used are shown in table 1. The glass fiber/polyamide materials prepared in examples 1 to 3 were tested for tensile strength according to the national standard GB/T1040-2006, the test results are shown in Table 2, and the test results of the polyamides PA6, PA66 and PA610 used are shown in Table 2.

TABLE 1 test results of the properties of the high-flow polyamide materials prepared in examples 1 to 3 and comparative examples

Performance index

Test standard

Example 1

Example 2

Example 3

PA6

PA66

PA610

Melt index (g/10 min)

ISO 1133

47

45

52

35

32

37

Table 2 shows the performance test results of the glass fiber/polyamide materials prepared in examples 1 to 3 and comparative examples

Performance index	Test standard	Example 1	Example 2	Example 3	PA6	PA66	PA610
								Tensile Strength (MPa)	GB/T1040-2006	185	190	150	80	85	60
Flexural Strength (MPa)	GB/T9341-2006	252	245	210	128	133	90
								Notched impact strength (kJ/m)2）	GB/T1043-2008	15	13	11	5.5	5	5.5

The data in tables 1 and 2 show that the tensile strength, flexural strength and notched impact strength specifications of the star polyamide of the invention are significantly higher than those of the prior art PA6 PA66 PA 610. The star polyamide prepared in example 1, nylon 6, was subjected to a fluorescence irradiation test, and FIG. 1 shows that the star polyamide did not emit light under 365nm light irradiation, and FIG. 2 shows that the star polyamide did not emit light under 365nm light irradiation. FIG. 3 is a fluorescent spectrum of star polyamide. FIG. 4 and FIG. 5 are the appearance of the fluorescence of the perylene anhydride/nylon 6 star polymer, wherein: FIG. 4 shows luminescence under 365nm light irradiation, and FIG. 5 shows no luminescence without 365nm light irradiation.

Example 4

Adding hexafluoroisopropyl phthalic anhydride into DMSO, and ultrasonically mixing for 1.5h at 75 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 20 mg/mL;

the dianhydride solution obtained in the step is added into a polymerization reactor of polyamide 6 in the early stage of polymerization, namely before the polymerization reaction is started, and the addition amount is 2% of the weight of the raw materials of the polymerization monomers. Reacting for 3 h at the temperature of 150 +/-5 ℃ to obtain star polyamide 6;

the star polyamide 6, the polyamide 6 and the graphene obtained in the step II are blended by a double-screw extruder according to the weight ratio of 5% to 85% to 10%, the extrusion temperature is 250 ℃, and then the carbon material/polyamide composite material is obtained through granulation by a granulator.

Example 5

Adding 3,3',4,4' -biphenyl tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 1.5 hours at 75 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 30 mg/mL;

adding adipic acid and hexamethylene diamine into a reaction kettle, and polymerizing through a polycondensation mechanism; the dianhydride solution obtained in the step is added into a polymerization reactor of polyamide 66 in the middle of polymerization, namely 2 hours after the polymerization reaction is started, and the addition amount is 4% of the weight of the raw materials of the polymerization monomers. Reacting for 4 hours at the temperature of 150 +/-5 ℃ to obtain star polyamide 66;

the star polyamide 66, the polyamide 66 and the carbon nano tube obtained in the step II are blended by a double-screw extruder according to the weight ratio of 8% to 82% to 10%, the extrusion temperature is 250 ℃, and then the carbon material/polyamide composite material is obtained through granulation by a granulator.

Example 6:

adding 3,3',4,4' -diphenyl sulfone tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 1.5h at 67 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 40 mg/mL;

adding terephthalic acid and hexamethylene diamine into a reaction kettle, and polymerizing by an anionic polymerization mechanism; the dianhydride solution obtained in the step is added into a polymerization reactor of poly-p-phenylene terephthamide in the later polymerization stage, namely, the dianhydride solution is added when the polymerization reaction is about to end, and the adding amount is 6% of the weight of the raw materials of the polymerization monomers. Reacting for 5 hours at the temperature of 145 +/-5 ℃ to obtain star polyamide;

and thirdly, blending the star polyamide, the poly (p-phenylene terephthalamide) and the graphite ore obtained in the second step according to the weight ratio of 10% to 60% to 30% by using a double-screw extruder, wherein the extrusion temperature is 250 ℃, and then granulating by using a granulator to obtain the carbon material/polyamide composite material.

Example 7:

adding pyromellitic dianhydride and 4,4' -oxydiphthalic anhydride into DMSO, and ultrasonically mixing for 1.5h at 67 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 50 mg/mL;

adding adipic acid and decamethylene diamine into a reaction kettle, and polymerizing through a polycondensation mechanism; the dianhydride solution obtained in the step is added into a polyamide 610 polymerization reactor in the middle polymerization stage, namely after 2.5 hours of polymerization reaction, and the adding amount is 8% of the weight of the raw materials of the polymerization monomers. Reacting for 5h at the temperature of 155 +/-2 ℃ to obtain star polyamide 610;

the star polyamide 610, the polyamide 610 and the carbon black obtained in the step II are blended by a double-screw extruder according to the weight ratio of 10% to 55% to 35%, the extrusion temperature is 260 ℃, and then the carbon material/polyamide composite material is obtained through granulation by a granulator.

Example 8

Adding perylen-3, 4,9, 10-tetracarboxylic dianhydride and 3,3',4,4' -benzophenone tetracarboxylic dianhydride into DMSO, and ultrasonically mixing for 1.5 hours at 65 +/-2 ℃ to prepare a dianhydride solution with the mass concentration of 50 mg/mL;

adding terephthalic acid and hexamethylene diamine into a reaction kettle, and polymerizing through a polycondensation mechanism; the dianhydride solution obtained in the step is added into a poly (hexamethylene terephthalamide) polymerization reactor in the middle polymerization stage, namely after the polymerization reaction 2, and the adding amount is 10% of the weight of the raw materials of the polymerization monomers. Reacting for 5 hours at the temperature of 155 +/-2 ℃ to obtain star-shaped poly (hexamethylene terephthalamide);

and thirdly, blending the star poly (hexamethylene terephthalamide), the poly (hexamethylene terephthalamide) and the carbon black obtained in the second step according to the weight ratio of 10% to 55% to 35% by using a double-screw extruder, wherein the extrusion temperature is 260 ℃, and then granulating by using a granulator to obtain the carbon material/polyamide composite material.

The carbon material/polyamide composite material prepared in examples 4 to 8 was tested for tensile strength according to the national standard GB/T1040-2006, for flexural strength according to the GB/T9341-2006 standard, and for notched impact strength according to the GB/T1043-2008, and the test results are shown in Table 3.

Table 3 Performance test results provided by Polyamide materials prepared in examples 4 to 7 and comparative examples

Performance index	Test standard	Example 4	Example 5	Example 6	Example 7	Example 8
							Tensile Strength (MPa)	GB/T1040-2006	132	128	120	112	137
Flexural Strength (MPa)	GB/T9341-2006	175	182	190	150	201
							Notched impact strength (kJ/m)2）	GB/T1043-2008	14.5	16	9	11	9.5