Polyphenyl ether-nylon 6 composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of engineering composite materials, and particularly discloses a polyphenyl ether-nylon 6 composite material and a preparation method and application thereof.The polyphenyl ether-nylon 6 composite material creatively realizes modification of polyphenyl ether by introducing grafted nylon 6 into a side group of polyphenyl ether, so that the polyphenyl ether and the nylon 6 have good compatibility, and the polyphenyl ether-nylon 6 composite material is prepared. The negative influence of the auxiliary agent on the performance of the polyphenyl ether / nylon 6 alloy is effectively avoided. In addition, the polyphenyl ether / nylon 6 composite material is prepared in an in-situ hydrolytic polymerization mode, the raw materials are simple and easy to obtain, the overall process is short, the technological process is easy to control, the production efficiency is high, and the obtained product has excellent mechanical properties and thermal stability, is low in moisture absorption rate and has a wide application range and market economic benefits.

Description

Technical Field

[0001] The present invention relates to an engineering composite material, in particular to a polyethersulfone-nylon composite material and a preparation method and application thereof, belonging to the technical field of engineering composite materials. Background Art

[0002] PA6, commonly known as nylon 6 or polycaprolactam, is one of the two most in-demand polyamide varieties in engineering plastics, and its output occupies an absolute dominant position. PA6 is a milky white or slightly yellow transparent solid with a high crystallinity of up to 33%. It is insoluble in general organic solvents and has excellent solvent resistance. However, due to the presence of amide bonds, pure PA6 has a high hygroscopicity, resulting in poor dimensional stability and heat resistance, and is easily aged in outdoor environments, which in turn leads to a decrease in mechanical properties. Unmodified PA6 is difficult to meet the needs of certain applications. In order to improve its comprehensive performance, Wang Yu (Textile Science Research, 2020, (1): 78-80) reported common modification methods for nylon 6, including blending modification, copolymerization modification, filling reinforcement modification and nanocomposite modification. These methods improve the performance of nylon 6 by blending one or more polymers, inorganic materials, nanomaterials, etc. with nylon 6 through physical or chemical reactions.

[0003] Polyphenylene ether, like nylon 6, is one of the five major engineering plastics. As early as the 1960s, General Electric Company of the United States began industrial production of polyphenylene ether. Compared with PA6, polyphenylene ether has obvious advantages in mechanical properties, with higher rigidity, good thermal stability, excellent dimensional stability, and excellent properties such as hydrolysis resistance, radiation resistance and flame retardancy. Blending of polyphenylene ether with PA6 can effectively improve the hygroscopicity, dimensional stability and mechanical properties of PA6. However, due to the huge difference in chemical structure between polyphenylene ether and PA6, their compatibility is poor. Therefore, when preparing polyphenylene ether / nylon 6 alloys, it is usually necessary to add a compatibilizer. Fan Yuwei et al. ("Engineering Plastics Application", 2021, Vol. 42, No. 10, 50-54) reported a method for toughening modification of polyphenylene ether and nylon 6 blends. This method compatibilizes and toughens PA6 / PPE alloys by adding a compatibilizer, maleic anhydride grafted polyphenylene ether (PPE-g-MAH), and further adding toughening agents, such as maleic anhydride grafted ethylene-octene copolymer (POE-g-MAH) and maleic anhydride grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH). Ma Mei et al. (Journal of Synthetic Materials, 2014, Vol. 43, No. 5, pp. 19-21, 77) reported a method for compatibilizing and modifying polyphenylene ether (PPE) blends with nylon 6. By adding a self-made compatibilizer, a well-compatible polyphenylene ether / nylon 6 alloy was prepared. Yang Junzhong et al. (CN201710311520.8) reported a nylon 6 / PPE composition and its preparation method. By adding a commercially available compatibilizer, a polyphenylene ether / nylon 6 alloy with excellent mechanical properties was obtained. In addition, Zhao Yanan (CN201110407228.9, CN201110407257.5) proposed a polyphenylene ether / nylon 6 alloy material, its preparation method, and applications, as well as a halogen-free flame-retardant polyphenylene ether / nylon 6 alloy, its preparation method, and applications. By adding additives such as compatibilizers, toughening agents, and flame retardants, they successfully prepared a polyphenylene ether / nylon 6 alloy with excellent performance. However, using these additives to improve the properties of the polyphenylene ether / nylon 6 alloy may result in a decrease in the crystallization rate and even a reduction in its flexural and tensile properties. Summary of the Invention

[0004] In order to solve the problem in the prior art that the poor compatibility between polyphenylene ether and nylon 6 (PA6) leads to a decrease in the performance of the composite material due to the addition of additives, the present invention provides a polyphenylene ether-nylon 6 composite material, a preparation method and use thereof. By introducing carboxyl groups into the side groups of polyphenylene ether and performing in-situ polymerization to prepare a polyphenylene ether / nylon 6 alloy (PPO-g-PA6), the compatibility of polyphenylene ether and nylon 6 can be significantly improved without the addition of additional additives, avoiding the negative impact of the additives on the performance of the polyphenylene ether / PA6 alloy, thereby obtaining a composite material with excellent overall performance.

[0005] In order to achieve the above technical objectives, the technical solutions adopted by the present invention are specifically described as follows:

[0006] According to a first embodiment of the present invention, a polyphenylene ether-nylon 6 composite material is provided:

[0007] A polyphenylene ether-nylon 6 composite material, comprising or consisting of nylon 6 and a polymer having a general structural formula (I). The polymer having a general structural formula (I) is as follows:

[0008] (I).

[0009] In the general structural formula (I), 0<x<1, 0<y<1, and x+y=1. The value of n is 1-200, preferably 50-150, and more preferably 80-120.

[0010] Preferably, in the composite material, the mass content of the polymer having the general structural formula (I) is not less than 0.5%, preferably 5 to 30%, and more preferably 10 to 25%.

[0011] Preferably, the tensile strength of the composite material is not less than 60 MPa, preferably not less than 65 MPa, and more preferably not less than 70 MPa.

[0012] Preferably, the flexural strength of the composite material is not less than 80 MPa, preferably not less than 85 MPa, and more preferably not less than 90 MPa.

[0013] Preferably, the heat deformation temperature of the composite material is not lower than 70°C, preferably not lower than 75°C, more preferably not lower than 80°C.

[0014] According to a second embodiment of the present invention, a method for preparing a polyphenylene ether-nylon 6 composite material is provided:

[0015] A method for preparing a polyphenylene ether-nylon 6 composite material or a method for preparing the polyphenylene ether-nylon 6 composite material as described in the first embodiment, the method comprising:

[0016] 1) Under a protective atmosphere, polyphenylene ether and a strong base are first subjected to a hydrogen extraction reaction in a solvent, and then dry ice is added to continue the reaction. Finally, after acidification, beating, filtering, and drying, a pendant carboxyl polyphenylene ether resin having the general structural formula (II) is obtained:

[0017] .

[0018] 2) Adding a pendant carboxyl polyphenylene ether resin having the general structural formula (II), caprolactam, and water into an autoclave, first performing a hydrolysis reaction under a protective atmosphere, and then sequentially performing heating and exhausting, reduced pressure polymerization, water washing, and drying to obtain a composite material containing a polymer having the general structural formula (I):

[0019] .

[0020] Wherein: 0<x<1, 0<y<1, and x+y=1. The value of n is 1-200, preferably 50-150, and more preferably 80-120.

[0021] Preferably, in step 1), the strong base is an organic strong base. Preferably, the strong organic base is one or more of n-butyllithium, sec-butyllithium, and tert-butyllithium (more preferably n-butyllithium).

[0022] Preferably, in step 1), the solvent is a mixed solvent consisting of a good solvent and a poor solvent for polyphenylene ether. Preferably, the good solvent is one or more of benzene, anisole, and tetrahydrofuran (more preferably tetrahydrofuran). The poor solvent is an alkane and / or a cycloalkane (more preferably one or more of n-hexane, cyclohexane, and cycloheptane). The volume ratio of the good solvent to the poor solvent is 1-10:1-10.

[0023] Preferably, in step 1), the molar ratio of the strong base to the polyphenylene ether structural unit is 0.01 to 1:1, preferably 0.05 to 0.2:1. The mass ratio of the solvent to the polyphenylene ether is 100:1 to 100, preferably 100:3 to 30. The molar weight of the polyphenylene ether structural unit is calculated by dividing the mass of the polyphenylene ether by the relative molecular weight of the structural unit (approximately 121 g / mol).

[0024] Preferably, in step 1), the carboxylation degree of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) is 1 to 40%, preferably 5 to 30%.

[0025] Preferably, in step 2), the mass ratio of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) to caprolactam is 2-30:70-98, preferably 5-25:75-95, and more preferably 10-20:80-90. The mass of water is 3-8%, preferably 4-6%, of the total mass of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) and caprolactam.

[0026] Preferably, in step 1) to step 2), the protective atmosphere is a nitrogen atmosphere or an inert gas atmosphere, preferably a nitrogen atmosphere.

[0027] Preferably, step 1) comprises the following steps: Under a protective atmosphere, polyphenylene ether and a solvent are first added to a mechanically stirred reaction vessel and stirred until swollen. A strong base solution is then added dropwise to the reaction vessel to carry out a hydrogen extraction reaction. The reaction temperature is 30-60°C and the reaction time is 0.5-3 hours. After the reaction is complete, the reaction system is added to dry ice (generally 1.5-5 times the mass of the reaction system). After the dry ice evaporates naturally, hydrochloric acid (preferably 5-15 mol / L) is added to adjust the reaction system to an acidic state (preferably a pH of 1-3) for acidification (preferably for 10-30 minutes). After the acidification is completed, the acidified liquid is added dropwise to a pulping solvent (preferably one or more of methanol, ethanol, and petroleum ether) for pulping. After the pulping is completed, filtration (preferably suction filtration) is performed to obtain a filter cake, and the filter cake is washed (preferably with methanol and water in sequence) and dried (preferably at a drying temperature of 60 to 100° C. and a drying time of 5 to 12 hours) to obtain a side carboxyl polyphenylene ether resin having the general structural formula (II).

[0028] Preferably, step 2) is specifically as follows: adding a side carboxyl polyphenylene ether resin having the general structural formula (II), caprolactam and water into a high-pressure reactor, then introducing a protective gas to replace the air in the reactor 1 to 10 times, then heating to 180 to 280° C. (preferably 200 to 260° C.) for hydrolysis reaction for 0.5 to 6 hours (preferably 1 to 4 hours), and then heating to 220 to 300° C. (preferably 240 to 280° C.) for further reaction for 0.5 to 6 hours. (preferably 1-4 hours), after the reaction is completed, the pressure is exhausted to normal pressure, and then reduced pressure polymerization is carried out until the viscosity is qualified (preferably, the reduced pressure polymerization is gradually carried out within 0.5-6 hours until the negative pressure value is -0.05 MPa to -0.09 MPa), and then pelletized to obtain solid particles, and the solid particles are washed with deionized water 1-10 times, and finally dried (preferably at a drying temperature of 60-100° C. and for 6-15 hours) to obtain a composite material containing a polymer having the general structural formula (I).

[0029] According to a third embodiment of the present invention, there is provided a use of a polyphenylene ether-nylon 6 composite material:

[0030] A use of a polyphenylene ether-nylon 6 composite material, or the use of the polyphenylene ether-nylon 6 composite material as described in the first embodiment, or the use of the polyphenylene ether-nylon 6 composite material prepared by the method described in the second embodiment, wherein the polyethersulfone-nylon composite material is used as a plastic.

[0031] In the present invention, research has found that the poor compatibility of polyphenylene ether and PA6 after blending is primarily due to the significant difference in their polarity, making them difficult to mix well. Furthermore, to avoid the negative impact of additives on the properties of the polyphenylene ether / PA6 alloy and thereby produce a composite material with excellent overall performance, the present invention considers improving the compatibility of the two phases by directly enhancing the interaction at the interface between the polyphenylene ether and PA6 phases, without the addition of additives. The inventors conducted in-depth research and discovered that by introducing carboxyl groups into the pendant groups of polyphenylene ether and then copolymerizing them with caprolactam to produce the polyphenylene ether / PA6 alloy through in-situ polymerization, the compatibility of the polyphenylene ether and PA6 can be significantly improved without the use of additives.

[0032] In the present invention, carboxyl groups are introduced into the pendant groups of polyphenylene ether to produce a pendant carboxyl polyphenylene ether resin. Subsequently, during copolymerization with caprolactam, the pendant carboxyl groups can be used as bridges to graft PA6 onto the polyphenylene ether segments, resulting in a polyphenylene ether-grafted PA6 material. While retaining the excellent thermal stability, dimensional stability, and hydrolysis, radiation, and flame retardancy properties of polyphenylene ether, the grafted PA6 side chains significantly reduce the polarity difference between the polyphenylene ether and PA6, resulting in excellent compatibility between the polyphenylene ether-grafted PA6 material and PA6. In a preferred embodiment, the carboxyl groups introduced into the pendant groups of the polyphenylene ether ensure a carboxylation degree of 1 to 40% (preferably 5 to 30%). Within this range, the subsequent grafting with PA6 ensures that the original properties of the polyphenylene ether are retained as much as possible, thereby ensuring the production of a composite material with excellent overall performance. It should be noted that, in the present invention, the degree of carboxylation of polyphenylene ether refers to the molar ratio of the number of structural units containing carboxyl groups to the total number of structural units, which can be calculated by 1 The peak area of ​​methylene and benzene ring in the HNMR graph is calculated using the formula x=a / b, where x is the degree of carboxylation of the polyphenylene ether, a refers to the peak area of ​​the nuclear magnetic shift of hydrogen on the methylene, and b refers to the peak area of ​​the nuclear magnetic shift of hydrogen on the benzene ring. Figure 1 For example: Figure 1 As shown, using deuterated chloroform as solvent, the side carboxyl polyphenylene ether obtained in Example 1 has a methylene peak connected to the carboxyl group at a chemical shift of around 3.5 ppm, indicating that the carboxyl group is successfully introduced into the side methyl group of the polyphenylene ether; the degree of carboxylation of the polyphenylene ether is x=a / b, wherein: the peak area a of the nuclear magnetic shift of hydrogen on the methylene is about 1, and the peak area b of the nuclear magnetic shift of hydrogen on the benzene ring is about 20, that is, the degree of carboxylation of the polyphenylene ether is about 5%.

[0033] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0034] 1: The present application is based on the deficiency of the current polyphenyl ether modified nylon 6, and initiatively realizes the modification of polyphenyl ether by introducing grafted PA6 into the side group of polyphenyl ether, so that the modified polyphenyl ether (i.e. the polymer having the structural general formula (I)) has good compatibility with PA6, and completely does not need to add additional additives, effectively avoiding the negative influence of the additives on the performance of polyphenyl ether / PA6 alloy.

[0035] 2: The polyphenyl ether / nylon 6 composite material is prepared by in-situ hydrolysis polymerization, the raw materials are simple and easy to obtain, the overall process is short, the process is easy to control, and the production efficiency is high, the obtained product has excellent mechanical properties and thermal stability, and low moisture absorption rate, and has wide application range, such as in the fields of aerospace, automobile manufacturing, electronic communication and the like, and has great practical application value. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 It is a synthesis line diagram of the polyphenyl ether-nylon 6 composite material of the present application.

[0037] Figure 2 It is the nuclear magnetic resonance hydrogen spectrum diagram of the side carboxyl polyphenyl ether resin obtained in example 1 of the present application.

[0038] Figure 3 It is the GPC curve diagram of the side carboxyl polyphenyl ether resin obtained in example 1 of the present application.

[0039] Figure 4 It is the DSC curve diagram of the side carboxyl polyphenyl ether resin obtained in example 1 of the present application.

[0040] Figure 5 It is the thermal gravimetric curve diagram of the composite material obtained in examples 1-3 and comparative examples 1-2 of the present application.

[0041] Figure 6 It is the DSC curve diagram of the composite material obtained in examples 1-3 and comparative examples 1-2 of the present application.

[0042] Figure 7 It is the field emission scanning electron microscope diagram of the good solvent etched polyphenyl ether of the brittle fracture surface of the composite material obtained in example 2 of the present application.

[0043] Figure 8 It is the field emission scanning electron microscope diagram of the good solvent etched polyphenyl ether of the brittle fracture surface of the composite material obtained in comparative example 1 of the present application.

[0044] Figure 9 It is the field emission scanning electron microscope diagram of the good solvent etched polyphenyl ether of the brittle fracture surface of the PA6 material obtained in comparative example 2 of the present application. DETAILED DESCRIPTION

[0045] The technical solutions of the present invention are illustrated below with examples, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0046] Example 1

[0047] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 375 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.3). After acidification, the reaction solution was added dropwise to 5 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 5% as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0048] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 950 g of caprolactam, 50 g of the side carboxyl polyphenylene ether resin prepared above and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 6.3%).

[0049] Example 2

[0050] 1) Preparation of the side carboxyl polyphenyl ether resin: 484 g of polyphenyl ether, 1250 mL of benzene and 1250 mL of cyclohexane were first added to a 5 L four-necked flask with mechanical stirring under N2 atmosphere to swell; then 375 mL of n-butyllithium solution (1.6 mol / L) in n-hexane was slowly added dropwise to the reaction system, after the dropwise addition was completed, the reaction was carried out at 45°C for 1 hour, then the reaction liquid was poured into 5 kg dry ice, after the dry ice was naturally volatilized, 40 mL of concentrated hydrochloric acid with a concentration of about 12 mol / L was added for acidification (the pH during acidification was about 1.5); after the acidification was completed, the reaction liquid was added dropwise into 5 L of methanol for beating, after the beating was completed, the filter cake was obtained by suction filtration, the filter cake was washed with methanol and water for 3 times respectively, then the filter cake was dried at 80°C for 10 h to obtain the side carboxyl polyphenyl ether resin, and the carboxylation degree was about 5% calculated by nuclear magnetic resonance hydrogen spectrum.

[0051] 2) Side carboxyl polyphenyl ether / caprolactam hydrolysis polymerization: 900 g of caprolactam, 100 g of the side carboxyl polyphenyl ether resin prepared above and 45 mL of water were added to a high-pressure reaction kettle, after the air in the reaction kettle was replaced 3 times by nitrogen, it was first heated to 220°C for hydrolysis for 2 hours, then heated to 260°C for reaction for 2 hours; after the reaction was completed, the exhaust and pressure reduction polymerization were carried out within 2 h until the negative pressure value was -0.07 MPa, then the discharge was carried out for pelletizing to obtain solid particles; finally, the solid particles were first washed with deionized water for 3 times, then dried at 80°C for 12 h to obtain polyphenyl ether-nylon 6 composite material particles (after detection, the mass content of the polymer with structural formula (I) therein was about 11.4%).

[0052] Example 3

[0053] 1) Preparation of the side carboxyl polyphenyl ether resin: 484 g of polyphenyl ether, 1250 mL of benzene and 1250 mL of cyclohexane were first added to a 5 L four-necked flask with mechanical stirring under N2 atmosphere to swell; then 375 mL of n-butyllithium solution (1.6 mol / L) in n-hexane was slowly added dropwise to the reaction system, after the dropwise addition was completed, the reaction was carried out at 45°C for 1 hour, then the reaction liquid was poured into 5 kg dry ice, after the dry ice was naturally volatilized, 40 mL of concentrated hydrochloric acid with a concentration of about 12 mol / L was added for acidification (the pH during acidification was about 1.5); after the acidification was completed, the reaction liquid was added dropwise into 5 L of methanol for beating, after the beating was completed, the filter cake was obtained by suction filtration, the filter cake was washed with methanol and water for 3 times respectively, then the filter cake was dried at 80°C for 10 h to obtain the side carboxyl polyphenyl ether resin, and the carboxylation degree was about 5% calculated by nuclear magnetic resonance hydrogen spectrum.

[0054] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen gas. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 16.3%).

[0055] Example 4

[0056] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.6). After acidification, the reaction solution was added dropwise to 5 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0057] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 950 g of caprolactam, 50 g of the side carboxyl polyphenylene ether resin prepared above and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 7.5%).

[0058] Example 5

[0059] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of cycloheptane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 40 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 2.0). After acidification, the reaction solution was added dropwise to 5 L of methanol to slurry. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0060] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 900 g of caprolactam, 100 g of the side carboxyl polyphenylene ether resin prepared above, and 45 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen, and then the temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 12.7%).

[0061] Example 6

[0062] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 45 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.8). After acidification, the reaction solution was added dropwise to 5 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0063] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen gas. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 17.6%).

[0064] Example 7

[0065] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 75 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 5 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 2.6). After acidification, the reaction solution was added dropwise to 5 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was calculated by hydrogen nuclear magnetic resonance spectroscopy to be approximately 1%.

[0066] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen gas. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 15.1%).

[0067] Example 8

[0068] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 1125 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 50°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 60 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 2.1). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 8 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 15%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0069] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen gas. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 10 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 18.7%).

[0070] Example 9

[0071] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 10-L four-necked flask with a mechanical stirrer and stirred to dissolve. 1500 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 55°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 100 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.5). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 12 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 20%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0072] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 14 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 19.9%).

[0073] Example 10

[0074] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 10-L four-necked flask with a mechanical stirrer and stirred to dissolve. 2250 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the reaction was incubated at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 120 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the solution (the pH during acidification was approximately 1.8). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the solution was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 30%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0075] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 21.6%).

[0076] Example 11

[0077] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 10-L four-necked flask with a mechanical stirrer and stirred to dissolve. 3000 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 150 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.9). After acidification, the reaction solution was added dropwise to 10 L of methanol to slurry. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain the side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 30%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0078] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 850 g of caprolactam, 150 g of the side carboxyl polyphenylene ether resin prepared above and 42.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the pressure was gradually exhausted and polymerized within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 22.8%).

[0079] Example 12

[0080] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.6). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0081] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 800 g of caprolactam, 200 g of the side carboxyl polyphenylene ether resin prepared above, and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen, and then the temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 21.1%).

[0082] Example 13

[0083] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.6). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0084] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 750 g of caprolactam, 250 g of the side carboxyl polyphenylene ether resin prepared above and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 26.3%).

[0085] Example 14

[0086] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.6). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0087] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 700 g of caprolactam, 300 g of the side carboxyl polyphenylene ether resin prepared above, and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen, and then the temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 31.2%).

[0088] Example 15

[0089] 1) Preparation of side-carboxyl polyphenylene ether resin: Under a nitrogen atmosphere, 484 g of polyphenylene ether, 1250 mL of tetrahydrofuran, and 1250 mL of n-hexane were added to a 5 L four-necked flask with a mechanical stirrer and stirred to dissolve. 750 mL of a 1.6 mol / L n-butyllithium solution in n-hexane was then slowly added dropwise to the reaction system. After the addition was complete, the mixture was reacted at 45°C for 1 hour. The reaction solution was then poured into 5 kg of dry ice. After the dry ice evaporated naturally, 50 mL of approximately 12 mol / L concentrated hydrochloric acid was added to acidify the mixture (the pH during acidification was approximately 1.6). After acidification, the reaction solution was added dropwise to 10 L of methanol for slurrying. After slurrying, the mixture was filtered to obtain a filter cake. The filter cake was washed three times with methanol and three times with water. The filter cake was then dried at 80°C for 10 h to obtain side-carboxyl polyphenylene ether resin. The degree of carboxylation was approximately 10%, as calculated by hydrogen nuclear magnetic resonance spectroscopy.

[0090] 2) Hydrolysis polymerization of side carboxyl polyphenylene ether / caprolactam: 980 g of caprolactam, 20 g of the side carboxyl polyphenylene ether resin prepared above and 47.5 mL of water were added to a high-pressure reactor. The air in the reactor was replaced three times by nitrogen. The temperature was first raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After completion of the reaction, the reaction was gradually vented and decompressed within 2 hours until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed three times with deionized water and then dried at 80°C for 12 hours to obtain polyphenylene ether-nylon 6 composite material pellets (after testing, the mass content of the polymer with structural formula (I) was approximately 4.6%).

[0091] Comparative Example 1

[0092] Polyphenylene ether / caprolactam hydrolysis polymerization: 900 g of caprolactam, 150 g of polyphenylene ether resin and 45 mL of water were added to a high-pressure reactor. Nitrogen was introduced to replace the air in the reactor three times, and then the temperature was raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the gas was gradually exhausted and the pressure was reduced within 2 hours to polymerize until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed with deionized water three times and then dried at 80°C for 14 hours to obtain polyphenylene ether-nylon 6 composite material pellets.

[0093] Comparative Example 2

[0094] 1000 g of caprolactam and 50 mL of water were added to a high-pressure reactor. Nitrogen was introduced to replace the air in the reactor three times, and then the temperature was raised to 220°C for hydrolysis for 2 hours, and then the temperature was raised to 260°C for reaction for 2 hours. After the reaction was completed, the air was gradually exhausted and the pressure was reduced within 2 hours to polymerize until the negative pressure value was -0.07 MPa, and then the material was discharged and pelletized to obtain solid particles. Finally, the solid particles were washed with deionized water three times and then dried at 80°C for 12 hours to obtain nylon 6 material pellets.

[0095] Performance testing:

[0096] The pellets prepared in Examples 1-6 and Comparative Examples 1-2 were subjected to tensile strength, flexural strength, notched impact strength, heat distortion temperature, and water absorption tests. Tensile properties were tested according to GB / T 1040.2-2006, using a 50 mm gauge length, an initial distance between clamps of 115 mm, a preferred thickness of 4 mm, a narrow portion of 10 mm, I-type test strips, and a testing rate of 10 mm / min.

[0097] The bending properties were tested according to GB / T 9341-2008, with a sample size of 80 × 10 × 4 mm, a support span of 64 mm, and a test rate of 2 mm / min.

[0098] The notched impact strength is measured according to the national standard GB / T 1043-1993. Five samples are taken from each group of test specimens for testing, and the average value is taken as the final test result.

[0099] The heat deformation temperature is tested according to the national standard GB / T1634-2004. The sample is placed flat, the sample size is 80mm×10mm×4mm, the pressure is 1.8 MPa, and the heating rate is 50℃ / hour.

[0100] Water absorption was tested according to ASTM D570. The sample was dried in an oven at 80°C until its mass stopped changing. The mass of the dried sample was recorded as the initial mass W0. The dried sample was then immersed in room temperature water for 24 hours. The sample was removed, the surface moisture was wiped off, and the sample was allowed to stand in air for 24 hours. This was recorded as the wet weight W. t .

[0101] Water absorption (%) = (W t -W0) / W0×100%.

[0102] The test results are shown in Table 1 below:

[0103] Table 1 Results of performance test data of pellets in various embodiments and comparative examples

[0104]

[0105] The molecular weight of polyphenylene ether was characterized using a gel permeation chromatography instrument model 1515 produced by Waters, Germany. Chromatographic grade tetrahydrofuran was used as the solvent at a concentration of 10-20 mg / mL to obtain the GPC curve. Polystyrene with different molecular weights was used as the standard sample to draw the standard calibration curve.

[0106] The glass transition temperatures of polyphenylene ether, nylon 6 and composite materials were characterized using a differential scanning calorimeter (DSC25) from TA Company in the United States. Under a nitrogen atmosphere, the temperature was first increased from room temperature to 300°C at a rate of 20°C / min, then cooled to 25°C at a rate of 10°C / min, and finally heated to 250°C at a rate of 10°C / min. The second heating curve was recorded and the glass transition temperature was obtained by analysis.

[0107] from Figure 3 It can be seen that the molecular weight of PPO does not change much before and after the side carboxyl modification. Figure 4 It can be seen that the PPO modified with side carboxyl groups still has excellent thermal properties.

[0108] The thermal stability of the composite material was characterized using a TA-Q50 thermogravimetric analyzer from TA Company of the United States. 3-8 mg of sample was weighed and heated from 30°C to 800°C at a heating rate of 10°C / min in a nitrogen atmosphere to obtain a thermogravimetric curve. Figure 5 It can be seen that the composite materials obtained in Examples 1 to 3 of the present invention all have excellent thermal stability, and the thermal decomposition temperature is higher than that of pure nylon 6.

[0109] Characterization of the compatibility of the composite material: The etched surface was photographed using a JEOL model JSM-IT800 field emission scanning electron microscope. The composite material bending strength test specimen was placed in liquid nitrogen for cooling, and then fractured to obtain a flat brittle fracture surface. The etched surface was obtained by soaking in chloroform for 3 hours and then drying. Figures 7-9 As shown, Figure 8 There are many large voids in Comparative Example 1, while Figure 7 and Figure 9 The surface of Example 2 and PA6 is relatively smooth, and Figure 7 Only small voids exist in Example 2, indicating that the compatibility of the side chain carboxylated polyphenylene ether with nylon 6 is better than that of the unmodified polyphenylene ether.

[0110] In the present invention, the sources of the raw materials used in the embodiments and comparative examples are as follows:

[0111] Polyphenylene ether was purchased from Nantong Xingchen Synthetic Materials Co., Ltd.

[0112] Tetrahydrofuran was purchased from Tianjin Kemeiou Chemical Co., Ltd.

[0113] n-Hexane was purchased from Tianjin Fuyu Fine Chemical Co., Ltd.

[0114] Cyclohexane was purchased from Tianjin Fuyu Fine Chemical Co., Ltd.

[0115] Benzene was purchased from Tianjin Fuyu Fine Chemical Co., Ltd.

[0116] Cycloheptane was purchased from Tianjin Fuyu Fine Chemical Co., Ltd.

[0117] n-Butyl lithium was purchased from Anhui Zesheng Technology Co., Ltd.

[0118] Dry ice was purchased from Changsha Bohan Biotechnology Co., Ltd.

[0119] Concentrated hydrochloric acid was purchased from Hunan Huihong Reagent Co., Ltd.

[0120] Methanol was purchased from Hunan Huihong Reagent Co., Ltd.

[0121] Caprolactam was purchased from Sinopec Hunan Petrochemical Co., Ltd.

[0122] Nitrogen was purchased from Hunan Zhongtai Hongyuan Gas Co., Ltd.

Claims

1. A polyphenylene ether-nylon 6 composite material, characterized by: The composite material includes or consists of nylon 6 and a polymer having a general structural formula (I); wherein the polymer having a general structural formula (I) is as follows: （I）； In the general structural formula (I), 0<x<1, 0<y<1, and x+y=1; n is 1-200, preferably 50-150, and more preferably 80-120.

2. The composite material according to claim 1, characterized in that: In the composite material, the mass content of the polymer having the general structural formula (I) is not less than 0.5%, preferably 5 to 30%, and more preferably 10 to 25%.

3. The composite material according to claim 1 or 2, characterized in that: The tensile strength of the composite material is not less than 60 MPa, preferably not less than 65 MPa, more preferably not less than 70 MPa; and / or The flexural strength of the composite material is not less than 80 MPa, preferably not less than 85 MPa, and more preferably not less than 90 MPa.

4. The composite material according to any one of claims 1 to 3, characterized in that: The heat deformation temperature of the composite material is not lower than 70°C, preferably not lower than 75°C, and more preferably not lower than 80°C.

5. A method for preparing a polyphenylene ether-nylon 6 composite material or a method for preparing a polyphenylene ether-nylon 6 composite material according to any one of claims 1 to 4, characterized in that: The method includes: 1) Under a protective atmosphere, polyphenylene ether and a strong base are first subjected to a hydrogen extraction reaction in a solvent, and then dry ice is added to continue the reaction. Finally, after acidification, beating, filtering, and drying, a pendant carboxyl polyphenylene ether resin having the general structural formula (II) is obtained: ； 2) Adding a pendant carboxyl polyphenylene ether resin having the general structural formula (II), caprolactam, and water into an autoclave, first performing a hydrolysis reaction under a protective atmosphere, and then sequentially performing heating and exhausting, reduced pressure polymerization, water washing, and drying to obtain a composite material containing a polymer having the general structural formula (I): ； Wherein: 0<x<1, 0<y<1, and x+y=1; n is 1-200, preferably 50-150, more preferably 80-120.

6. The method according to claim 5, characterized in that: In step 1), the strong base is an organic strong base; preferably, the strong organic base is one or more of n-butyllithium, sec-butyllithium, and tert-butyllithium (more preferably n-butyllithium); and / or In step 1), the solvent is a mixed solvent consisting of a good solvent and a poor solvent for polyphenylene ether; preferably, the good solvent is one or more of benzene, anisole, and tetrahydrofuran (more preferably tetrahydrofuran); the poor solvent is an alkane and / or a cycloalkane (more preferably one or more of n-hexane, cyclohexane, and cycloheptane); the mixed volume ratio of the good solvent to the poor solvent is 1-10:1-10; Preferably, in step 1), the molar ratio of the strong base to the polyphenylene ether structural unit is 0.01-1:1, preferably 0.05-0.2:1; the mass ratio of the solvent to the polyphenylene ether is 100:1-100, preferably 100:3-30; Preferably, in step 1), the carboxylation degree of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) is 1 to 40%, preferably 5 to 30%.

7. The preparation method according to claim 5 or 6, characterized in that: In step 2), the mass ratio of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) to caprolactam is 2-30:70-98, preferably 5-25:75-95, and more preferably 10-20:80-90; the mass of water is 3-8%, preferably 4-6%, of the total mass of the pendant carboxyl polyphenylene ether resin having the general structural formula (II) and caprolactam; Preferably, in step 1) to step 2), the protective atmosphere is a nitrogen atmosphere or an inert gas atmosphere, preferably a nitrogen atmosphere.

8. The method according to any one of claims 5 to 7, characterized in that: Step 1) is specifically as follows: under a protective atmosphere, polyphenylene ether and a solvent are first added to a reaction vessel with mechanical stirring and stirred until swelling, and then a strong base solution is added dropwise to the reaction vessel for a hydrogen extraction reaction, the reaction temperature is 30-60°C, and the reaction time is 0.5-3h; after the reaction is completed, the reaction system is added to dry ice, and after the dry ice is naturally evaporated, hydrochloric acid (preferably 5-15 mol / L) is added to adjust the reaction system to acidity (preferably pH 1-3) for acidification (preferably acidification time is 10-30min); after the acidification is completed, the acidified liquid is added dropwise to a pulping solvent (preferably one or more of methanol, ethanol, and petroleum ether) for pulping treatment, and after the pulping is completed, filtering (preferably suction filtration) to obtain a filter cake, washing the filter cake (preferably using methanol and water in sequence) and drying (preferably drying temperature is 60-100°C, drying time is 5-12h) to obtain a side carboxyl polyphenylene ether resin having the general structural formula (II).

9. The method according to any one of claims 5 to 8, characterized in that: Step 2) is as follows: A side carboxyl polyphenylene ether resin having the general structural formula (II), caprolactam and water are added to an autoclave, and then a protective gas is introduced to replace the air in the autoclave 1 to 10 times. The reaction is then heated to 180 to 280° C. (preferably 200 to 260° C.) for a hydrolysis reaction for 0.5 to 6 hours (preferably 1 to 4 hours), and then heated to 220 to 300° C. (preferably 240 to 280° C.) for a further reaction for 0.5 to 6 hours (preferably 1 to 4 hours). After the reaction is completed, the reaction is evacuated to normal pressure and then polymerized under reduced pressure until the viscosity reaches a satisfactory level (preferably, the polymerization is gradually reduced under reduced pressure within 0.5 to 6 hours until the negative pressure reaches -0.05 MPa to -0.09 MPa). The reaction is then pelletized to obtain solid particles, and the solid particles are washed with deionized water 1 to 10 times. Finally, the composite material containing the polymer having the general structural formula (I) is obtained by drying (preferably at a drying temperature of 60 to 100° C. for 6 to 15 hours).

10. Use of a polyphenylene ether-nylon 6 composite material, or use of the polyphenylene ether-nylon 6 composite material according to any one of claims 1 to 4, or use of the polyphenylene ether-nylon 6 composite material prepared by the method according to any one of claims 5 to 9, characterized in that: The polyethersulfone-nylon composite material is used as the plastic.

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