Modified polyphenylene sulfide composite material and preparation process thereof

Abstract

The invention relates to a modified polyphenylene sulfide composite material and a preparation process thereof, and belongs to the technical field of high polymer materials. The composite material is prepared from polyphenylene sulfide resin, modified reinforced fibers, a modified carbon nanotube-polyimide mixture, a compatilizer, a talcum powder / mica powder mixture and an antioxidant according to certain parts by mass. Wherein the modified reinforced fibers are prepared by oxidizing carbon fibers with potassium permanganate and reacting with glass fibers and the like; the modified carbon nanotube-polyimide mixture is prepared by acidifying the carbon nanotube, modifying with polyethylene glycol 400 and the like, and compounding with polyimide. The talcum powder / mica powder mixture is prepared by ball-milling and mixing. The preparation process comprises the following steps: treating the talcum powder / mica powder mixture and the silane coupling agent to form the activated filler, mixing the raw materials, performing melt extrusion through a twin-screw extruder, performing water-cooling granulation, and drying to obtain the product. The composite material has excellent performance, the preparation process is simple and controllable, and the composite material can be widely applied to the fields of electronics, automobiles and the like.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a modified polyphenylene sulfide composite material and its preparation process. Background Technology

[0002] Polyphenylene sulfide (PPS) is a high-performance thermoplastic resin with excellent heat resistance, corrosion resistance, and dimensional stability, and is widely used in automotive, electronics, aerospace, and other fields. However, PPS has some drawbacks, such as its brittleness and low impact strength, which limits its use in applications requiring high impact resistance. Therefore, modifying PPS to improve its performance and expand its application range is of great significance. Existing technologies often modify PPS by adding glass fibers, inorganic fillers, or blending with other polymers, but these methods suffer from poor interfacial bonding and insufficient thermal stability. Therefore, there is an urgent need to develop a modified PPS material with strong interfacial bonding and excellent overall performance. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a modified polyphenylene sulfide composite material and its preparation process, in order to solve the problem of low impact strength of existing polyphenylene sulfide composite materials, and to provide a modified polyphenylene sulfide composite material with high impact strength and its preparation process.

[0004] Technical solution: A modified polyphenylene sulfide composite material, characterized in that it contains the following raw materials in parts by weight: 60-80 parts of polyphenylene sulfide resin, 15-30 parts of modified reinforcing fiber, 5-10 parts of modified carbon nanotube-polyimide mixture, 1-3 parts of compatibilizer, 0.5-2 parts of talc / mica powder mixture, and 0.1-0.5 parts of antioxidant.

[0005] Preferably, the modified reinforcing fiber preparation method is as follows: carbon fiber is added to a reaction flask, deionized water with a weight of 4 times the weight of the carbon fiber is added, ultrasonic stirring is performed for 5 minutes, potassium permanganate with a weight of 0.1 times the weight of the deionized water is added, the mixture is heated to 60°C and stirred for 8 hours, filtered, washed with water until the washing water is colorless, and dried at 60°C to constant weight to obtain hydroxylated carbon fiber. The hydroxylated carbon fiber is added to a reaction flask, glass fiber with a weight of 2 times the weight of the hydroxylated carbon fiber is added, dichloromethane with a weight of 15 times the weight of the hydroxylated carbon fiber is added, and triethylamine with a weight of 2 times the weight of the hydroxylated carbon fiber is added under argon protection. Stirring is started, the system is cooled to 20°C, and terephthaloyl chloride with a weight of 3 times the weight of the hydroxylated carbon fiber is added dropwise at a temperature controlled below 40°C. After the addition is completed, the mixture is reacted at 40±5°C for 2 hours, filtered, the filter cake is washed with dichloromethane, and dried at 40°C to constant weight to obtain the final product.

[0006] Preferably, the modified carbon nanotube-polyimide mixture is prepared as follows: carbon nanotubes are added to a mixed acid of concentrated H2SO4 and concentrated HNO3 in a volume ratio of 3:1 (one times the weight of the carbon nanotubes) and heated to 60–70°C for 2–4 hours. The reaction solution is then slowly added dropwise to ice water (ten times the weight of the carbon nanotubes). The mixture is filtered, and the filter cake is washed until neutral and dried at 70°C to constant weight to obtain the corresponding hydroxyl-carboxyl carbon nanotubes. The hydroxyl-carboxyl carbon nanotubes are dispersed in DCM (five times the weight of the hydroxyl-carboxyl carbon nanotubes). Triphenylphosphine (1.2 times the weight of the hydroxyl-carboxyl carbon nanotubes) is added and stirred until dissolved. The mixture is then cooled to 0±5°C and then added dropwise at a controlled temperature of 5±5°C. DEAD, at a weight of 1.5 times the weight of hydroxy-carboxylated carbon nanotubes, was added dropwise. After the addition was complete, a DCM solution of polyethylene glycol 400, at a weight of 0.5 times the weight of hydroxy-carboxylated carbon nanotubes (DCM weight is twice the weight of polyethylene glycol 400), was slowly added dropwise at a temperature controlled at 5±5℃. The mixture was stirred at room temperature for 2 hours, centrifuged, and washed to obtain polyethylene glycol 400 modified carbon nanotubes. Polyimide powder, at a weight of 1 times the weight of polyethylene glycol 400 modified carbon nanotubes, was dissolved in THF, at a weight of 10 times the weight of polyimide. Polyimide 400 modified carbon nanotubes were added under stirring, and the mixture was concentrated under reduced pressure at 40℃ to 20% of its original volume under stirring. The solution was cooled to 10℃, filtered, and dried at 50℃ with a forced airflow until constant weight was obtained.

[0007] Preferably, the compatibilizer is either a polyepoxy silicone oil or a glycerol triepoxypropyl ether.

[0008] Preferably, the talc / mica powder mixture is prepared by adding talc powder and mica powder (0.5 times the weight of talc powder) to a ball mill for ball milling and mixing.

[0009] Preferably, the antioxidant is any one of antioxidant 1010, antioxidant 1076, or antioxidant 3114.

[0010] A preparation process for a modified polyphenylene sulfide composite material, the preparation process of the modified polyphenylene sulfide composite material includes: S1. Treat the talc / mica powder mixture with the silane coupling agent in a high-speed mixer at 80°C for 10 minutes to form an activated filler; S2. Add PPS resin, activated filler obtained in step S1, modified reinforcing fiber, modified carbon nanotube-polyimide mixture, antioxidant, and compatibilizer to a high-speed mixer and mix for 5 minutes under nitrogen protection, with the temperature controlled at 50-60℃. S3. The premixed material is fed from the main feed port of the twin-screw extruder, melt-extruded, water-cooled and granulated, and the granules are dried at 80°C to constant weight to obtain modified PPS composite material granules.

[0011] Preferably, in step S1, the amount of silane coupling agent used is 1.5% of the mass of the talc / mica powder mixture.

[0012] Preferably, in step S3, the screw temperature zones are set as follows: Zone 1 280℃, Zone 2 300℃, Zone 3 310℃, Zone 4 305℃, and the screw speed is 200-300 rpm. Beneficial effects

[0013] 1. Through a stepwise modification process, carbon fibers are first oxidized, and then terephthaloyl chloride is co-grafted with glass fibers. Polar groups and polymer chains are introduced on the fiber surface, so that the modified fibers and PPS resin form chemical bonds, which greatly improves the interfacial compatibility, increases the tensile strength and impact toughness of the composite material, and solves the problem of interfacial delamination in traditional fiber-reinforced PPS.

[0014] 2. A three-step method of "acid oxidation → Mitsunobu grafting PEG400 → polyimide coating" is adopted, in which the long chain of PEG400 improves the dispersion stability of carbon nanotubes in the resin; the polyimide shell inhibits the aggregation of carbon nanotubes and improves heat resistance; thus, the concentration threshold for the formation of conductive network in the composite material is reduced and the heat distortion temperature is increased.

[0015] 3. After ball milling and mixing talc / mica powder, the surface of the silane coupling agent is activated, which enhances the bonding force with the resin. Low-temperature premixing (50-60℃) avoids resin preplasticization and ensures component uniformity. Low-temperature drying at 80℃ prevents PPS particle crystallization and ensures the consistency of subsequent injection molding melt. The flexural modulus of the composite material is improved and the warpage of the injection molded product is reduced.

[0016] 4. Twin-screw extrusion employs stepped heating (280→310℃) and high rotation speed (200-300rpm) to achieve high shear dispersion while preventing PPS degradation, thereby improving the yield of extruded granules and production capacity. Attached Figure Description

[0017] Figure 1 This is a schematic SEM image of the modified reinforcing fiber of the present invention.

[0018] Figure 2 This is a schematic SEM image of the reinforcing fiber before modification according to the present invention.

[0019] Figure 3 This is a comparison of the infrared spectra of the reinforcing fibers before and after modification according to the present invention.

[0020] Figure 4 This is a SEM image of the modified carbon nanotube-polyimide mixture of the present invention. Detailed Implementation

[0021] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Example

[0022] Raw material ratio: PPS resin: 70 parts Modified reinforcing fiber: 22 parts Modified carbon nanotube-polyimide mixture: 7 parts Compatibilizer (polyepoxy silicone oil): 2 parts Talc / mica powder mixture (2:1): 1 part Antioxidant 1010 hindered phenol: 0.3 parts Preparation process: Preparation of modified reinforcing fibers: Add 100g of carbon fiber to a reaction flask, add 400g of deionized water, sonicate for 5 min, add 40g of potassium permanganate, heat to 60℃ and stir for 8 h, filter, wash with water until the wash water is colorless, and dry at 60℃ to constant weight to obtain hydroxylated carbon fiber. Add 100g of hydroxylated carbon fiber to a reaction flask, add 200g of glass fiber, add 1500g of dichloromethane, and under argon protection, add 200g of triethylamine, start stirring, cool the system to 20℃, and add 300g of terephthaloyl chloride dropwise while maintaining the temperature below 40℃. After the addition is complete, react at 40±5℃ for 2 h, filter, wash the filter cake with dichloromethane, and dry at 40℃ to constant weight to obtain the modified fiber. See attached SEM image of the modified fiber. Figure 1 The SEM image before modification is attached. Figure 2 The infrared spectra of the reinforced fibers before and after modification are shown in the appendix. Figure 3 .

[0023] Preparation of modified carbon nanotube-polyimide: 100g of carbon nanotubes were added to 100g of a mixed acid solution of concentrated H₂SO₄ and concentrated HNO₃ (volume ratio 3:1) and heated to 65℃ for 3 hours. The reaction solution was then slowly added dropwise to 1000g of ice water. The mixture was filtered, and the filter cake was washed until neutral and then dried at 70℃ to constant weight to obtain the corresponding hydroxy-carboxylated carbon nanotubes. 100g of the hydroxy-carboxylated carbon nanotubes were dispersed in 500g of DCM, and 120g of triphenylphosphine was added and stirred until dissolved. The mixture was then cooled to 0±5℃, and 150g of DEAD was added dropwise at a controlled temperature of 5±5℃. After the addition was complete... A DCM solution of polyethylene glycol 400 (100g DCM, 50g polyethylene glycol 400) was slowly added dropwise at 5℃. The mixture was stirred at room temperature for 2 hours, centrifuged, and washed to obtain polyethylene glycol 400-modified carbon nanotubes. 100g of polyimide powder was dissolved in 1000g THF, and 100g of polyethylene glycol 400-modified carbon nanotubes were added with stirring. The mixture was concentrated under reduced pressure at 40℃ with stirring to 200g, cooled to 10℃, filtered, and dried at 50℃ with forced air until constant weight was obtained. A SEM image of the modified carbon nanotube-polyimide mixture is attached. Figure 4 .

[0024] Composite material preparation: S1. 100g of talc / mica powder mixture (66.7g talc powder, 33.3g mica powder) and 1.5g silane coupling agent are treated in a high-speed mixer at 80℃ for 10 minutes to form an activated filler; S2. Add 700g PPS resin, 10g activated filler obtained in step S1, 220g modified reinforcing fiber, 70g modified carbon nanotube-polyimide mixture, 3g antioxidant, and 20g compatibilizer to a high-speed mixer and mix for 5 minutes under nitrogen protection, with the temperature controlled at 55℃. S3. The premixed material is extruded from the main feed port of the twin-screw extruder through twin-screw extrusion (280 / 300 / 310 / 305℃, 250rpm), water-cooled and granulated, and the granules are dried at 80℃ to constant weight to obtain modified PPS composite material granules. Example

[0025] Raw material ratio: PPS resin: 60 parts Modified reinforcing fiber: 30 parts Modified carbon nanotube-polyimide mixture: 10 parts Compatibilizer (glyceryl trioxypropyl ether): 1 part Talc / mica powder mixture: 0.5 parts Antioxidant 1076: 0.1 parts Preparation process: Preparation of modified reinforcing fibers: Add 100g of carbon fiber to a reaction flask, add 400g of deionized water, sonicate for 5 minutes, add 40g of potassium permanganate, heat to 60℃ and stir for 8 hours, filter, wash with water until the washing water is colorless, and dry at 60℃ to constant weight to obtain hydroxylated carbon fiber. Add 100g of hydroxylated carbon fiber to a reaction flask, add 200g of glass fiber, add 1500g of dichloromethane, and under argon protection, add 200g of triethylamine, start stirring, cool the system to 20℃, and add 300g of terephthaloyl chloride dropwise while controlling the temperature below 40℃. After the addition is complete, react at 40±5℃ for 2 hours, filter, wash the filter cake with dichloromethane, and dry at 40℃ to constant weight to obtain the final product.

[0026] Preparation of modified carbon nanotube-polyimide: 100g of carbon nanotubes were added to 100g of a mixed acid solution of concentrated H₂SO₄ and concentrated HNO₃ (volume ratio 3:1) and heated to 60℃ for 4 hours. The reaction solution was then slowly added dropwise to 1000g of ice water. The mixture was filtered, and the filter cake was washed until neutral and dried at 70℃ to constant weight to obtain the corresponding hydroxy-carboxylated carbon nanotubes. 100g of hydroxy-carboxylated carbon nanotubes were dispersed in 500g of DCM, and 120g of triphenylphosphine was added and stirred until dissolved. The mixture was then cooled to 0±5℃, and 150g of [unspecified substance] was added dropwise at a controlled temperature of 5±5℃. DEAD: After the addition is complete, slowly add a DCM solution of polyethylene glycol 400 (100g DCM, 50g polyethylene glycol 400) at a controlled temperature of 5℃. Stir at room temperature for 2 hours, centrifuge and wash to obtain polyethylene glycol 400 modified carbon nanotubes. Dissolve 100g polyimide powder in 1000g THF, add 100g polyethylene glycol 400 modified carbon nanotubes while stirring, concentrate under reduced pressure at 40℃ to 200g while stirring, cool to 10℃ and filter, dry at 50℃ with forced air to constant weight to obtain the final product.

[0027] Composite material preparation: S1. 100g of talc / mica powder mixture (66.7g talc powder, 33.3g mica powder) and 1.5g silane coupling agent are treated in a high-speed mixer at 80℃ for 10 minutes to form an activated filler; S2. Add 600g PPS resin, 5g activated filler obtained in step S1, 300g modified reinforcing fiber, 100g modified carbon nanotube-polyimide mixture, 1g antioxidant, and 10g compatibilizer to a high-speed mixer and mix for 5 minutes under nitrogen protection, with the temperature controlled at 50℃. S3. The premixed material is extruded from the main feed port of the twin-screw extruder through twin-screw extrusion (280 / 300 / 310 / 305℃, 200rpm), water-cooled and granulated, and the granules are dried at 80℃ to constant weight to obtain modified PPS composite material granules. Example

[0028] Raw material ratio: PPS resin: 80 parts Modified reinforcing fiber: 15 parts Modified carbon nanotube-polyimide mixture: 5 parts Compatibilizer (polyepoxy silicone oil): 3 parts Talc / mica powder mixture: 2 parts Antioxidant 3114: 0.5 parts Preparation process: Preparation of modified reinforcing fibers: Add 100g of carbon fiber to a reaction flask, add 400g of deionized water, sonicate for 5 minutes, add 40g of potassium permanganate, heat to 60℃ and stir for 8 hours, filter, wash with water until the washing water is colorless, and dry at 60℃ to constant weight to obtain hydroxylated carbon fiber. Add 100g of hydroxylated carbon fiber to a reaction flask, add 200g of glass fiber, add 1500g of dichloromethane, and under argon protection, add 200g of triethylamine, start stirring, cool the system to 20℃, and add 300g of terephthaloyl chloride dropwise while controlling the temperature below 40℃. After the addition is complete, react at 40±5℃ for 2 hours, filter, wash the filter cake with dichloromethane, and dry at 40℃ to constant weight to obtain the final product.

[0029] Preparation of modified carbon nanotube-polyimide: 100g of carbon nanotubes were added to 100g of a mixed acid solution of concentrated H₂SO₄ and concentrated HNO₃ (volume ratio 3:1) and heated to 70°C for 2 hours. The reaction solution was then slowly added dropwise to 1000g of ice water. The mixture was filtered, and the filter cake was washed until neutral and dried at 70°C to constant weight to obtain the corresponding hydroxy-carboxylated carbon nanotubes. 100g of hydroxy-carboxylated carbon nanotubes were dispersed in 500g of DCM, and 120g of triphenylphosphine was added and stirred until dissolved. The mixture was then cooled to 0±5°C, and 150g of [unspecified substance] was added dropwise at a controlled temperature of 5±5°C. DEAD: After the addition is complete, slowly add a DCM solution of polyethylene glycol 400 (100g DCM, 50g polyethylene glycol 400) at a controlled temperature of 5℃. Stir at room temperature for 2 hours, centrifuge and wash to obtain polyethylene glycol 400 modified carbon nanotubes. Dissolve 100g polyimide powder in 1000g THF, add 100g polyethylene glycol 400 modified carbon nanotubes while stirring, concentrate under reduced pressure at 40℃ to 200g while stirring, cool to 10℃ and filter, dry at 50℃ with forced air to constant weight to obtain the final product.

[0030] Composite material preparation: S1. 100g of talc / mica powder mixture (66.7g talc powder, 33.3g mica powder) and 1.5g silane coupling agent are treated in a high-speed mixer at 80℃ for 10 minutes to form an activated filler; S2. Add 800g PPS resin, 20g activated filler obtained in step S1, 150g modified reinforcing fiber, 50g modified carbon nanotube-polyimide mixture, 5g antioxidant, and 30g compatibilizer to a high-speed mixer and mix for 5 minutes under nitrogen protection, with the temperature controlled at 60℃. S3. The premixed material is extruded from the main feed port of the twin-screw extruder through twin-screw extrusion (280 / 300 / 310 / 305℃, 300rpm), water-cooled and granulated, and the granules are dried at 80℃ to constant weight to obtain modified PPS composite material granules.

[0031] Same as Example 1, except that the unmodified fibers are used directly, with raw carbon fiber + glass fiber (1:2).

[0032] Same as Example 1, except that the unmodified carbon nanotubes are physically mixed with polyimide.

[0033] Same as Example 1, except that the drying temperature is 120°C (instead of 80°C).

[0034] Same as Example 1, except that the S1 silane activation step is omitted.

[0035] Same as Example 1, except that only carbon fiber is oxidized (without co-grafting with glass fiber).

[0036] Same as Example 1, except that the carbon nanotubes are only acidified (without PEG400 grafting).

[0037] Table 1 Test Results of the Example The examples and comparative examples show that Example 1 has a 40% increase in tensile strength and an 88% increase in impact toughness compared to Comparative Example 1, indicating that stepwise fiber modification improves interfacial bonding. Comparative Example 5 demonstrates that the strength decreases by 21% without co-grafted glass fibers, indicating that terephthaloyl chloride bridging of the two fibers is key to interfacial reinforcement. Example 1 has a 6-order-of-magnitude decrease in resistivity and a 20°C increase in heat resistance compared to Comparative Example 2, indicating that the three-step method for carbon nanotubes optimizes dispersion and function. Comparative Example 6 demonstrates that the resistivity deteriorates by 40 times without PEG400 grafting (compared to Example 1), indicating that long-chain PEG... It is the core of constructing a conductive network; the warpage rate of Example 1 decreased by 81% compared to Comparative Example 3, and the flexural modulus of Example 1 increased by 31% compared to Comparative Example 4. It can be seen that the low temperature process ensures processing stability, while high temperature drying (Comparative Example 3) causes PPS pre-crystallization, which leads to injection molding warpage, and the unactivated filler (Comparative Example 4) significantly reduces rigidity; the pass rate of Example 1 increased by 5% compared to the Comparative Example, which can be seen that the extrusion process improves production efficiency. The synergistic effect of high speed (200-300 rpm) and step temperature rise (280→310℃) avoids carbon nanotube agglomeration and PPS degradation; the examples and comparative examples prove that when fiber stepwise grafting, carbon nanotube PEG-PI dual modification, and filler activation + low temperature process are simultaneously satisfied, the composite material achieves a synergistic leap in performance, which is suitable for high-precision electronic packaging parts (warpage rate <1%) and heat-resistant structural parts (HDT>260℃).

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A modified polyphenylene sulfide composite material, characterized in that, It is composed of the following raw materials in parts by weight: 60-80 parts of polyphenylene sulfide resin, 15-30 parts of modified reinforcing fiber, 5-10 parts of modified carbon nanotube-polyimide mixture, 1-3 parts of compatibilizer, 0.5-2 parts of talc / mica powder mixture, and 0.1-0.5 parts of antioxidant.

2. The modified polyphenylene sulfide composite material according to claim 1, characterized in that, The modified reinforcing fiber preparation method is as follows: Carbon fiber is added to a reaction flask, followed by deionized water at 4 times the weight of the carbon fiber. The mixture is ultrasonically stirred for 5 minutes, then potassium permanganate at 0.1 times the weight of the deionized water is added. The mixture is heated to 60°C and stirred for 8 hours. After filtration, the mixture is washed with water until the washing water is colorless. The mixture is then dried at 60°C to constant weight to obtain hydroxylated carbon fiber. The hydroxylated carbon fiber is then added to a reaction flask, followed by glass fiber at 2 times the weight of the hydroxylated carbon fiber, and dichloromethane at 15 times the weight of the hydroxylated carbon fiber. Under argon protection, triethylamine at 2 times the weight of the hydroxylated carbon fiber is added. The mixture is stirred and cooled to 20°C. The temperature is controlled below 40°C, and terephthaloyl chloride at 3 times the weight of the hydroxylated carbon fiber is added dropwise. After the addition is complete, the temperature is controlled at 40±5°C and the reaction is carried out for 2 hours. The mixture is then filtered, and the filter cake is washed with dichloromethane and dried at 40°C to constant weight to obtain the final product.

3. The modified polyphenylene sulfide composite material according to claim 1, characterized in that, The modified carbon nanotube-polyimide mixture is prepared as follows: Carbon nanotubes are added to a mixed acid solution of concentrated H₂SO₄ and concentrated HNO₃ at a volume ratio of 3:1 (one times the weight of the carbon nanotubes). The mixture is heated to 60–70°C for 2–4 hours. The reaction solution is then slowly added dropwise to ice water at a weight of 10 times the weight of the carbon nanotubes. The mixture is filtered, and the filter cake is washed until neutral and then dried at 70°C to constant weight to obtain the corresponding hydroxyl-carboxyl carbon nanotubes. The hydroxyl-carboxyl carbon nanotubes are dispersed in DCM at a weight of 5 times the weight of the hydroxyl-carboxyl carbon nanotubes. Triphenylphosphine at a weight of 1.2 times the weight of the hydroxyl-carboxyl carbon nanotubes is added and stirred until dissolved. The mixture is then cooled to 0±5°C and controlled... DEAD, weighing 1.5 times the weight of hydroxy-carboxylated carbon nanotubes, was added dropwise at 5±5℃. After the addition was complete, a DCM solution of polyethylene glycol 400, weighing 0.5 times the weight of hydroxy-carboxylated carbon nanotubes, was slowly added dropwise at 5±5℃. The mixture was stirred at room temperature for 2 hours, centrifuged, and washed to obtain polyethylene glycol 400 modified carbon nanotubes. Polyimide powder, weighing 1 times the weight of polyethylene glycol 400 modified carbon nanotubes, was dissolved in THF, weighing 10 times the weight of polyimide. Polyimide 400 modified carbon nanotubes were added under stirring, and the mixture was concentrated under reduced pressure at 40℃ to 20% of its original volume. The solution was cooled to 10℃, filtered, and dried at 50℃ with a forced airflow until constant weight was obtained.

4. The modified polyphenylene sulfide composite material according to claim 1, characterized in that, The compatibilizer is either polyepoxy silicone oil or glyceryl triepoxypropyl ether.

5. The modified polyphenylene sulfide composite material according to claim 1, characterized in that, The method for preparing the talc / mica powder mixture is as follows: talc powder and mica powder with a weight of 0.5 times that of talc powder are added to a ball mill and mixed by ball milling.

6. The modified polyphenylene sulfide composite material according to claim 1, characterized in that, The antioxidant is any one of antioxidant 1010, antioxidant 1076, or antioxidant 3114.

7. A preparation process for the modified polyphenylene sulfide composite material according to any one of claims 1 to 6, characterized in that, include: S1. Treat the talc / mica powder mixture with the silane coupling agent in a high-speed mixer at 80°C for 10 minutes to form an activated filler; S2. Add PPS resin, activated filler obtained in step S1, modified reinforcing fiber, modified carbon nanotube-polyimide mixture, antioxidant, and compatibilizer to a high-speed mixer and mix for 5 minutes under nitrogen protection, with the temperature controlled at 50-60℃. S3. The premixed material is fed from the main feed port of the twin-screw extruder, melt-extruded, water-cooled and granulated, and the granules are dried at 80°C to constant weight to obtain modified PPS composite material granules.

8. The preparation process of the modified polyphenylene sulfide composite material according to claim 7, characterized in that, In step S1, the amount of silane coupling agent used is 1.5% of the mass of the talc / mica powder mixture.

9. The preparation process of the modified polyphenylene sulfide composite material according to claim 7, characterized in that, In step S3, the screw temperature zones are set as follows: Zone 1 280℃, Zone 2 300℃, Zone 3 310℃, Zone 4 305℃, and the screw speed is 200-300 rpm.

Images