A high-temperature and high-pressure resistant cable for new energy vehicles and a preparation method thereof

Abstract

The application discloses a high-temperature and high-pressure resistant cable for new energy vehicles and a preparation method thereof, and relates to the technical field of cables.The cable comprises a cable core, an insulation layer and a sheath layer from inside to outside; the sheath layer material comprises polyimide, polyethylene, modified polyether ether ketone, modified polyphenylene sulfide, a compatibilizer, an anti-wear agent and an antioxidant; the modified polyether ether ketone is enhanced in thermal stability and interfacial bonding force by introducing titanium elements, imide groups and hydroxyl groups; the modified polyphenylene sulfide is improved in toughness and processability by grafting siloxane segments; and the compatibilizer is crosslinked by reacting with active functional groups in the modified polyether ether ketone and the modified polyphenylene sulfide, so as to improve the performance of the sheath layer.The cable prepared by the application has excellent high-temperature resistance, flame resistance, mechanical strength and long-term service stability, and is suitable for new energy vehicles.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. Background Technology

[0002] With the rapid development of new energy vehicles, cables, as core connectors in their high-voltage electrical systems, must withstand high voltage, high current, and high temperatures in the engine compartment for extended periods, while also possessing excellent flame retardancy, mechanical strength, and durability. The cable sheath, as the outermost protective barrier, directly determines the reliability, safety, and service life of the entire cable system through its material properties.

[0003] Currently, the industry faces the following bottlenecks in improving the temperature resistance and overall performance of cables: High-performance engineering plastics have performance shortcomings: 1. Although polyetheretherketone (PEEK) has excellent high-temperature resistance and flame retardant properties, the pure resin has poor toughness and is prone to brittleness. It also has poor interfacial compatibility with other components in the sheath layer. Simple blending can easily lead to a rapid decline in the overall performance of the material, which cannot meet the long-term stable service requirements of new energy vehicle cables; 2. Polyphenylene sulfide (PPS) is relatively brittle and has poor impact resistance. It also faces the problem of poor compatibility with other components. These defects make it difficult for PPS to maintain a high mechanical property retention rate after long-term high-temperature aging, which cannot meet the long-term and stable service requirements of high-voltage cables for new energy vehicles in extreme environments.

[0004] Therefore, in order to solve the above problems, this invention proposes a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. Summary of the Invention

[0005] The purpose of this invention is to provide a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method, so as to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A high-temperature and high-voltage resistant cable for new energy vehicles comprises, from the inside out, a cable core, an insulation layer, and a sheath layer; the sheath layer is prepared from a sheath layer material, which includes the following components by mass: 40-60 parts polyimide, 20-30 parts polyethylene, 10-15 parts modified polyetheretherketone, 10-15 parts modified polyphenylene sulfide, 0.5-1 part compatibilizer, 10-20 parts abrasion resistant agent, and 0.2-0.5 parts antioxidant; The modified polyether ether ketone contains elemental titanium and imide groups; The modified polyphenylene sulfide is an organosilicon-modified polyphenylene sulfide.

[0007] Furthermore, the modified polyether ether ketone is prepared by the following process: adding polyether ether ketone polymer and potassium borohydride into a dimethyl sulfoxide solution, reacting, washing and drying to obtain hydroxyl-containing modified polyether ether ketone; The molar ratio of polyetheretherketone polymer and potassium borohydride is 100:(0.05-1); the ratio of polyetheretherketone polymer and dimethyl sulfoxide solution is 1g:(8-15)mL.

[0008] Furthermore, the polyetheretherketone polymer is prepared by the following process: (1) Hydroquinone was added to diphenyl sulfone, and then tetrabutyl titanate was added to react and obtain titanium-containing phenolic compounds; (2) Diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and toluene were added to N-methylpyrrolidone. After reacting at 120-150℃ for 3-5 h, potassium carbonate was added for purification. After heating to dehydrate, precipitation, washing and drying, an imide-containing compound was obtained. (3) Add biphenyl and sodium carbonate to N-methylpyrrolidone and react under nitrogen protection. Then add 30-40% of the total mass of 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds in sequence and react. Finally, add the remaining 4,4'-difluorobenzophenone and react. After precipitation, washing and drying, the reaction solution is used to obtain polyether ether ketone polymer.

[0009] Furthermore, in step (1), the molar ratio of hydroquinone, diphenyl sulfone, and tetrabutyl titanate is (10-20):(100-130):(0.5-1); The reaction conditions are: temperature 60-80℃, time 4-8h.

[0010] Furthermore, in step (2), the molar ratio of diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and potassium carbonate is 1:(2-2.5):(2-2.5); the ratio of diphenyl ether tetracarboxylic dianhydride and N-methylpyrrolidone is 1g:(8-15)mL; and the volume ratio of toluene and N-methylpyrrolidone is (0.4-0.6):1.

[0011] Furthermore, in step (3), the molar ratio of biphenyl, sodium carbonate, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds is 1:(1-1.15):(0.9-1):(0.02-0.05):(0.03-0.08); the ratio of biphenyl to N-methylpyrrolidone is 1g:(6-10)mL.

[0012] Furthermore, the modified polyphenylene sulfide is prepared by the following process: Polyphenylene sulfide, acetyl chloride, and anhydrous ZnCl2 were added to a solvent and reacted to obtain acetylated polyphenylene sulfide; then, under nitrogen protection, acetylated polyphenylene sulfide, diamino-terminated polydimethylsiloxane, p-toluenesulfonic acid, and anhydrous magnesium sulfate were mixed and reacted to obtain modified polyphenylene sulfide. The solvent is dichloromethane; The molar ratio of polyphenylene sulfide, acetyl chloride and anhydrous ZnCl2 is 1:(0.5-1.5):(0.5-1); the ratio of polyphenylene sulfide to solvent is 1g:(10-20)mL; The molar ratio of acetylated polyphenylene sulfide, p-toluenesulfonic acid and anhydrous magnesium sulfate is 1:(0.05-0.1):(0.8-1.2); the ratio of acetylated polyphenylene sulfide and diamino-terminated polydimethylsiloxane is 1g:(2-3)mL.

[0013] Furthermore, the compatibilizer is maleic anhydride-grafted polyethylene.

[0014] Furthermore, the abrasion resistant agent is chopped aramid fiber; the antioxidant is a compound of antioxidant 1010 and antioxidant 168, with a mass ratio of antioxidant 1010 to antioxidant 168 of (0.8-1.2):1.

[0015] Furthermore, the thickness of the sheath layer is 1.5-3.0 mm.

[0016] Furthermore, the insulating layer is made of one or more of cross-linked polyethylene, ethylene-tetrafluoroethylene copolymer, polyolefin elastomer, and cross-linked polyolefin; the thickness of the insulating layer is 0.5-0.8 mm.

[0017] Furthermore, the cable core is obtained by winding mica tape around the conductor; the conductor is obtained by twisting multiple metal wires together; the metal wires are one of copper, aluminum, and aluminum alloy; the diameter of the cable core is 2.5-5mm.

[0018] A method for preparing a high-temperature and high-voltage resistant cable for new energy vehicles includes the following steps: Step 1: Twist multiple metal wires in the same direction to form a conductor, and spirally wrap mica tape around the conductor to obtain the cable core; Step 2: Use an extruder to extrude an insulation layer onto the surface of the cable core; Step 3: Use an extruder to extrude a sheath layer onto the surface of the insulation layer to prepare the cable.

[0019] Furthermore, in step three, the temperatures of each zone of the extruder are as follows: feeding zone 150-200℃, extrusion zone 1 230-250℃, extrusion zone 2 250-270℃, extrusion zone 3 270-290℃, die head temperature 270-290℃, and extrusion speed 30-50m / min.

[0020] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention describes a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. The invention uses polyimide as the matrix resin, combined with polyethylene, modified polyetheretherketone (PEEK), and modified polyphenylene sulfide (PPS) as auxiliary reinforcing components. Polyimide itself possesses excellent flame retardancy and electrical insulation properties, which can improve the safety level of the material system. Polyethylene improves the flexibility of the sheath layer. Through molecular design and surface treatment, modified PEEK not only significantly improves the upper limit of high temperature resistance and thermal stability of the material system but also enhances the interfacial bonding with other components. Modified PPS, by introducing flexible siloxane segments, effectively improves the melt processing performance and toughness of the material system and forms a synergistic reinforcing effect with modified PEEK, creating a high-performance resin blend system that significantly improves the upper limit of high temperature resistance, mechanical strength, and long-term service stability of the sheath layer.

[0021] 2. This invention describes a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. The polyetheretherketone polymer prepared by this invention is obtained by copolymerizing biphenyl, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds, and imide-containing compounds. During the polymerization of the titanium-containing phenolic compounds, elemental titanium is embedded into the main chain; during the polymerization of the imide-containing compounds, imide groups are introduced into the polymer main chain, thus obtaining a polyetheretherketone polymer containing elemental titanium and imide. Then, hydroxyl groups are introduced by potassium borohydride reducing agent to obtain modified polyetheretherketone. The elemental titanium, imide groups, and hydroxyl groups introduced into the molecular chain significantly enhance the rigidity and thermal stability of the molecular chain, giving the cable sheath excellent long-term high-temperature resistance, enabling the cable to maintain good mechanical properties and dimensional stability even in high-temperature environments.

[0022] 3. The present invention describes a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. The modified polyphenylene sulfide of the present invention introduces long chains of siloxane through chemical grafting. Siloxane itself has extremely high thermal stability, and its introduction also improves the melt flow and flexibility of polyphenylene sulfide. It can effectively toughen the sheath material and construct a rigid-flexible reinforcing network, so that the material can maintain excellent mechanical properties and dimensional stability at high temperatures.

[0023] 4. The present invention describes a high-temperature and high-voltage resistant cable for new energy vehicles and its preparation method. The anhydride groups in the compatibilizer used in the present invention can chemically react with the active functional groups (such as hydroxyl, mercapto, and amino groups) in modified polyether ether ketone and modified polyphenylene sulfide to form a chemically bonded three-dimensional network in the matrix. On the one hand, this network acts as a "skeleton structure," significantly improving the overall heat resistance and long-term service stability of the material; on the other hand, it acts as a "molecular bridge," greatly improving the compatibility between modified polyether ether ketone, modified polyphenylene sulfide, and polyethylene. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] In the following specific implementation: The production of this invention is shown in the following laboratory pilot test, which can be scaled up proportionally.

[0026] The raw materials involved in this invention are not subject to any special limitations, and exemplary components include: The polyetheretherketone (PEEK) grade is 450G; potassium borohydride has a CAS number of 13762-51-1 and a purity of 99%; dimethyl sulfoxide has a CAS number of 67-68-5 and a purity of 99%; hydroquinone has a CAS number of 123-31-9 and a purity of 99%; diphenyl sulfone has a CAS number of 127-63-9 and a purity of 99%; tetrabutyl titanate has a CAS number of 5593-70-4 and a purity of 99%; 3-amino-4-fluorophenol has a CAS number of 62257-16-3 and a purity of 99%. Toluene's CAS number is 108-88-3, and its purity is 99.8%; N-methylpyrrolidone's CAS number is 872-50-4, and its purity is 99.5%; potassium carbonate's CAS number is 584-08-7, and its purity is 99.9%; biphenyl hydroquinone's CAS number is 92-88-6, and its purity is 99%; sodium carbonate's CAS number is 497-19-8, and its purity is 99%; 4,4'-difluorobenzophenone's CAS number is 345-92-6, and its purity is 99%; dichloromethane's CAS number is... 75-09-2, purity 99%; polyphenylene sulfide grade CZ-1030; acetyl chloride CAS 75-36-5, purity 99%; anhydrous ZnCl2 CAS 7646-85-7, purity 99%; diamino-terminated polydimethylsiloxane CAS 106214-84-0, purity 98%, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; anhydrous magnesium sulfate CAS 7487-89-2, purity 99%; p-toluenesulfonic acid CAS 10 4-15-4, purity 99%; maleic anhydride grafted polyethylene grade TY1053H; chopped aramid fiber length 3mm, aspect ratio 50; antioxidant 1010 CAS 6683-19-8, purity 99%; antioxidant 168 CAS 31570-04-4, purity 98.5%; ethylene-tetrafluoroethylene copolymer grade EP-620; metal wire is aluminum wire, diameter 0.6mm; mica tape purchased from Yangzhou Shengkai Electrical Insulation Co., Ltd.

[0027] Example 1: A high-temperature and high-voltage resistant cable for new energy vehicles, comprising, from the inside out, a cable core, an insulation layer, and a sheath layer; the sheath layer is prepared from a sheath layer material, which includes the following components by mass: 50 parts polyimide, 25 parts polyethylene, 15 parts modified polyetheretherketone, 15 parts modified polyphenylene sulfide, 1 part compatibilizer, 15 parts abrasion resistant agent, and 0.2 parts antioxidant; The modified polyetheretherketone (PEEK) is prepared by the following process: adding the PEEK polymer and potassium borohydride to a dimethyl sulfoxide solution, reacting, washing and drying to obtain hydroxyl-containing modified PEEK; the molar ratio of PEEK polymer to potassium borohydride is 100:1; the ratio of PEEK polymer to dimethyl sulfoxide solution is 1g:10mL. Polyetheretherketone polymers are prepared by the following process: (1) Hydroquinone was added to diphenyl sulfone, and then tetrabutyl titanate was added. The reaction was carried out at 70°C for 6 hours to obtain a titanium-containing phenolic compound. The molar ratio of hydroquinone, diphenyl sulfone and tetrabutyl titanate was 10:100:1. (2) Diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and toluene were added to N-methylpyrrolidone. After reacting at 130°C for 4 h, potassium carbonate was added for purification. After heating to dehydrate, precipitation, washing and drying, an imide-containing compound was obtained. The molar ratio of diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and potassium carbonate was 1:2:2.2; the ratio of diphenyl ether tetracarboxylic dianhydride to N-methylpyrrolidone was 1 g:8 mL; the volume ratio of toluene to N-methylpyrrolidone was 0.5:1. (3) Bisphenol and sodium carbonate were added to N-methylpyrrolidone and reacted under nitrogen protection. Then, 35% of the total mass of 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds were added sequentially and reacted. Finally, the remaining 4,4'-difluorobenzophenone was added and reacted. After precipitation, washing and drying, polyetheretherketone polymer was obtained. The molar ratio of bisphenol, sodium carbonate, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds was 1:1:1:0.02:0.05. The ratio of bisphenol to N-methylpyrrolidone was 1g:8mL. Modified polyphenylene sulfide (PPS) is prepared by the following process: PPS, acetyl chloride, and anhydrous ZnCl2 are added to dichloromethane and reacted to obtain acetylated PPS; then, under nitrogen protection, acetylated PPS, diamino-terminated polydimethylsiloxane, p-toluenesulfonic acid, and anhydrous magnesium sulfate are mixed and reacted to obtain modified PPS; the molar ratio of PPS, acetyl chloride, and anhydrous ZnCl2 is 1:0.5:0.5; the ratio of PPS to dichloromethane is 1 g:15 mL; the molar ratio of acetylated PPS, p-toluenesulfonic acid, and anhydrous magnesium sulfate is 1:0.05:0.8; and the ratio of acetylated PPS to diamino-terminated polydimethylsiloxane is 1 g:2 mL. The compatibilizer is maleic anhydride-grafted polyethylene; the abrasion resistant agent is chopped aramid fiber; the antioxidant is a compound of antioxidant 1010 and antioxidant 168, with a mass ratio of antioxidant 1010 to antioxidant 168 of 1:1. The thickness of the sheath layer is 2mm; The insulating layer is made of ethylene-tetrafluoroethylene copolymer and has a thickness of 0.5 mm. The diameter of the cable core is 5mm; A method for preparing a high-temperature and high-voltage resistant cable for new energy vehicles includes the following steps: Step 1: Twist multiple metal wires in the same direction to form a conductor, and spirally wrap mica tape around the conductor to obtain the cable core; Step 2: Use an extruder to extrude an insulation layer onto the surface of the cable core; Step 3: Use an extruder to extrude the sheath layer onto the surface of the insulation layer to prepare the cable; the temperatures of each zone of the extruder are: 180℃ for the feeding zone, 240℃ for the first extrusion zone, 260℃ for the second extrusion zone, 280℃ for the third extrusion zone, 280℃ for the die head, and the extrusion speed is 40m / min.

[0028] Example 2: A high-temperature and high-voltage resistant cable for new energy vehicles, comprising, from the inside out, a cable core, an insulation layer, and a sheath layer; the sheath layer is prepared from a sheath layer material, which includes the following components by weight: 40 parts polyimide, 20 parts polyethylene, 12 parts modified polyetheretherketone, 12 parts modified polyphenylene sulfide, 0.8 parts compatibilizer, 10 parts abrasion resistant agent, and 0.3 parts antioxidant; The modified polyetheretherketone (PEEK) was prepared by the following process: adding the PEEK polymer and potassium borohydride to a dimethyl sulfoxide solution, reacting, washing and drying to obtain hydroxyl-containing modified PEEK; the molar ratio of the PEEK polymer to potassium borohydride was 100:0.05; the ratio of the PEEK polymer to the dimethyl sulfoxide solution was 1g:8mL. Polyetheretherketone polymers are prepared by the following process: (1) Hydroquinone was added to diphenyl sulfone, and then tetrabutyl titanate was added. The reaction was carried out at 60°C for 8 hours to obtain a titanium-containing phenolic compound. The molar ratio of hydroquinone, diphenyl sulfone and tetrabutyl titanate was 15:110:0.8. (2) Diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and toluene were added to N-methylpyrrolidone. After reacting at 120°C for 5 h, potassium carbonate was added for purification. After dehydration by heating, precipitation and washing and drying, an imide-containing compound was obtained. The molar ratio of diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and potassium carbonate was 1:2.2:2; the ratio of diphenyl ether tetracarboxylic dianhydride to N-methylpyrrolidone was 1 g:8 mL; the volume ratio of toluene to N-methylpyrrolidone was 0.4:1. (3) Bisphenol and sodium carbonate were added to N-methylpyrrolidone and reacted under nitrogen protection. Then, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds were added in sequence and reacted. Finally, the remaining 4,4'-difluorobenzophenone was added and reacted. After precipitation, washing and drying, polyetheretherketone polymer was obtained. The molar ratio of bisphenol, sodium carbonate, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds was 1:1.1:0.9:0.03:0.03. The ratio of bisphenol to N-methylpyrrolidone was 1g:6mL. Modified polyphenylene sulfide (PPS) is prepared by the following process: PPS, acetyl chloride, and anhydrous ZnCl2 are added to dichloromethane and reacted to obtain acetylated PPS; then, under nitrogen protection, acetylated PPS, diamino-terminated polydimethylsiloxane, p-toluenesulfonic acid, and anhydrous magnesium sulfate are mixed and reacted to obtain modified PPS; the molar ratio of PPS, acetyl chloride, and anhydrous ZnCl2 is 1:1:0.8; the ratio of PPS to dichloromethane is 1 g:10 mL; the molar ratio of acetylated PPS, p-toluenesulfonic acid, and anhydrous magnesium sulfate is 1:0.08:1; and the ratio of acetylated PPS to diamino-terminated polydimethylsiloxane is 1 g:2.5 mL. The compatibilizer is maleic anhydride-grafted polyethylene; the abrasion resistant agent is chopped aramid fiber; the antioxidant is a compound of antioxidant 1010 and antioxidant 168, with a mass ratio of antioxidant 1010 to antioxidant 168 of 0.8:1. The thickness of the sheath layer is 1.5mm; The insulating layer is made of ethylene-tetrafluoroethylene copolymer and has a thickness of 0.6 mm. The diameter of the cable core is 2.5mm; A method for preparing a high-temperature and high-voltage resistant cable for new energy vehicles includes the following steps: Step 1: Twist multiple metal wires in the same direction to form a conductor, and spirally wrap mica tape around the conductor to obtain the cable core; Step 2: Use an extruder to extrude an insulation layer onto the surface of the cable core; Step 3: Use an extruder to extrude the sheath layer onto the surface of the insulation layer to prepare the cable; the temperatures of each zone of the extruder are: 150℃ for the feeding zone, 230℃ for the first extrusion zone, 250℃ for the second extrusion zone, 270℃ for the third extrusion zone, 270℃ for the die head, and the extrusion speed is 30m / min.

[0029] Example 3: A high-temperature and high-voltage resistant cable for new energy vehicles, comprising, from the inside out, a cable core, an insulation layer, and a sheath layer; the sheath layer is prepared from a sheath layer material, which includes the following components by weight: 60 parts polyimide, 30 parts polyethylene, 10 parts modified polyetheretherketone, 10 parts modified polyphenylene sulfide, 0.5 parts compatibilizer, 20 parts abrasion resistant agent, and 0.5 parts antioxidant; The modified polyetheretherketone (PEEK) is prepared by the following process: adding the PEEK polymer and potassium borohydride to a dimethyl sulfoxide solution, reacting, washing and drying to obtain hydroxyl-containing modified PEEK; the molar ratio of the PEEK polymer to potassium borohydride is 100:1; the ratio of the PEEK polymer to the dimethyl sulfoxide solution is 1g:15mL. Polyetheretherketone polymers are prepared by the following process: (1) Hydroquinone was added to diphenyl sulfone, and then tetrabutyl titanate was added. The reaction was carried out at 80°C for 4 hours to obtain a titanium-containing phenolic compound. The molar ratio of hydroquinone, diphenyl sulfone and tetrabutyl titanate was 20:130:0.5. (2) Diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and toluene were added to N-methylpyrrolidone. After reacting at 150°C for 3 h, potassium carbonate was added for purification. After heating to dehydrate, precipitation, washing and drying, an imide-containing compound was obtained. The molar ratio of diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and potassium carbonate was 1:2.5:2.5; the ratio of diphenyl ether tetracarboxylic dianhydride to N-methylpyrrolidone was 1 g:15 mL; the volume ratio of toluene to N-methylpyrrolidone was 0.6:1. (3) Bisphenol and sodium carbonate were added to N-methylpyrrolidone and reacted under nitrogen protection. Then, 40% of the total mass of 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds were added sequentially and reacted. Finally, the remaining 4,4'-difluorobenzophenone was added and reacted. After precipitation, washing and drying, the reaction solution was used to obtain polyether ether ketone polymer. The molar ratio of bisphenol, sodium carbonate, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds was 1:1.15:1:0.05:0.08. The ratio of bisphenol to N-methylpyrrolidone was 1g:10mL. Modified polyphenylene sulfide (PPS) is prepared by the following process: PPS, acetyl chloride, and anhydrous ZnCl2 are added to dichloromethane and reacted to obtain acetylated PPS; then, under nitrogen protection, acetylated PPS, diamino-terminated polydimethylsiloxane, p-toluenesulfonic acid, and anhydrous magnesium sulfate are mixed and reacted to obtain modified PPS; the molar ratio of PPS, acetyl chloride, and anhydrous ZnCl2 is 1:1.5:1; the ratio of PPS to dichloromethane is 1 g:20 mL; the molar ratio of acetylated PPS, p-toluenesulfonic acid, and anhydrous magnesium sulfate is 1:0.1:1.2; and the ratio of acetylated PPS to diamino-terminated polydimethylsiloxane is 1 g:3 mL. The compatibilizer is maleic anhydride-grafted polyethylene; the abrasion resistant agent is chopped aramid fiber; the antioxidant is a compound of antioxidant 1010 and antioxidant 168, with a mass ratio of antioxidant 1010 to antioxidant 168 of 1.2:1. The thickness of the sheath layer is 3mm; The insulating layer is made of ethylene-tetrafluoroethylene copolymer and has a thickness of 0.8 mm. The diameter of the cable core is 4mm; A method for preparing a high-temperature and high-voltage resistant cable for new energy vehicles includes the following steps: Step 1: Twist multiple metal wires in the same direction to form a conductor, and spirally wrap mica tape around the conductor to obtain the cable core; Step 2: Use an extruder to extrude an insulation layer onto the surface of the cable core; Step 3: Use an extruder to extrude the sheath layer onto the surface of the insulation layer to prepare the cable; the temperatures of each zone of the extruder are: 200℃ for the feeding zone, 250℃ for the first extrusion zone, 270℃ for the second extrusion zone, 290℃ for the third extrusion zone, 290℃ for the die head, and the extrusion speed is 50m / min.

[0030] Comparative Example 1: Based on Example 1, the modified polyether ether ketone was replaced with a polyether ether ketone polymer. The only difference from Example 1 is that the sheath material includes the following components by weight: 50 parts polyimide, 25 parts polyethylene, 15 parts polyether ether ketone polymer, 15 parts modified polyphenylene sulfide, 1 part compatibilizer, 15 parts abrasion resistant agent, and 0.2 parts antioxidant.

[0031] Comparative Example 2: Based on Example 1, the modified polyphenylene sulfide was replaced with polyphenylene sulfide. The only difference from Example 1 is that the sheath material includes the following components by weight: 50 parts polyimide, 25 parts polyethylene, 15 parts modified polyether ether ketone, 15 parts polyphenylene sulfide, 1 part compatibilizer, 15 parts abrasion resistant agent, and 0.2 parts antioxidant.

[0032] Comparative Example 3: Based on Example 1, without the addition of compatibilizer, the only difference from Example 1 is that the sheath material includes the following components by weight: 50 parts polyimide, 25 parts polyethylene, 15 parts modified polyether ether ketone, 15 parts modified polyphenylene sulfide, 15 parts abrasion resistant agent, and 0.2 parts antioxidant.

[0033] Comparative Example 4: Based on Example 1, the modified polyetheretherketone was replaced with polyetheretherketone, and the modified polyphenylene sulfide was replaced with polyphenylene sulfide. The only difference from Example 1 is that the sheath material includes the following components by weight: 50 parts polyimide, 25 parts polyethylene, 15 parts polyetheretherketone, 15 parts polyphenylene sulfide, 1 part compatibilizer, 15 parts abrasion resistant agent, and 0.2 parts antioxidant.

[0034] Experiment: Samples were prepared from the sheath layers of the cables obtained in Examples 1-3 and Comparative Examples 1-4. Their performance was tested, and the results were recorded. Tensile strength and elongation at break tests: The mechanical properties of the samples were tested according to GB / T 2951.11-2008, with a tensile speed of 200 mm / min. Tensile strength retention rate test: The sample was aged at 200℃ for 30 days. According to the standard GB / T 2951.11-2008, the initial tensile strength and the tensile strength after 30 days of aging were measured, and the tensile strength retention rate was calculated. Tensile strength retention rate = tensile strength after 30 days of aging / initial tensile strength × 100%; Limiting Oxygen Index (LOI) Test: Refer to standard GB / T 2406.2-2009 to conduct a limiting oxygen index test on the cable. The sample size is 100mm×6.5mm×3mm.

[0035]

[0036] Conclusion: As can be seen from the data comparison in Table 1, the performance of the sheath layers prepared in Comparative Examples 1-4 is significantly reduced compared to those prepared in Examples 1-3.

[0037] Comparative Examples 1-4, based on Example 1, showed significantly worse performance of the sheath layer after adjusting its formulation and preparation method. Comparative Example 1 (replacing modified polyetheretherketone with a polyetheretherketone polymer): The worse performance of the sheath layer indicates that the hydroxyl groups introduced in the modified polyetheretherketone chemically bond with the compatibilizer, thereby improving the material's thermal stability and interfacial bonding. Comparative Example 2 (replacing modified polyphenylene sulfide with polyphenylene sulfide): Its mechanical properties and thermal stability decreased, confirming that the introduction of siloxane segments effectively improved the material's toughness. Comparative Example 3 (no compatibilizer added): The worse performance of the sheath layer indicates that the compatibilizer chemically interacts with the active functional groups in the modified polyetheretherketone and modified polyphenylene sulfide, further enhancing the material system's thermal stability and interfacial bonding. Comparative Example 4 (unmodified polyetheretherketone and polyphenylene sulfide): The significantly worse performance of the sheath layer confirms the necessity of modifying polyetheretherketone and polyphenylene sulfide.

[0038] In summary, this invention constructs a high-performance sheath material system that combines rigidity and flexibility with strong interfacial bonding through the synergistic compounding of polyimide, polyethylene, modified polyetheretherketone, modified polyphenylene sulfide, and compatibilizer. This system not only achieves a balance between high mechanical strength and excellent heat resistance, but also possesses good flame retardancy and long-term service stability, fully meeting the stringent service requirements of high-voltage cables for new energy vehicles under high temperature, high voltage, and high mechanical stress environments.

[0039] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A high-temperature and high-voltage resistant cable for new energy vehicles, characterized in that: High-temperature and high-voltage resistant cables consist of a cable core, an insulation layer, and a sheath layer from the inside out. The sheath layer is prepared from a sheath layer material, which comprises the following components by weight: 40-60 parts polyimide, 20-30 parts polyethylene, 10-15 parts modified polyetheretherketone, 10-15 parts modified polyphenylene sulfide, 0.5-1 parts compatibilizer, 10-20 parts abrasion resistant agent, and 0.2-0.5 parts antioxidant; The modified polyphenylene sulfide is an organosilicon-modified polyphenylene sulfide; The modified polyether ether ketone is prepared by the following process: adding polyether ether ketone polymer and potassium borohydride into a dimethyl sulfoxide solution, reacting, washing and drying to obtain hydroxyl-containing modified polyether ether ketone; The polyetheretherketone polymer is prepared by the following steps: (1) Hydroquinone was added to diphenyl sulfone, and then tetrabutyl titanate was added to react and obtain titanium-containing phenolic compounds; (2) Diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and toluene were added to N-methylpyrrolidone. After reacting at 120-150℃ for 3-5 h, potassium carbonate was added for purification. After heating to dehydrate, precipitation, washing and drying, an imide-containing compound was obtained. (3) Biphenyl and sodium carbonate were added to N-methylpyrrolidone and reacted under nitrogen protection. Then, 4,4'-difluorobenzophenone, titanium-containing phenolic compounds and imide-containing compounds were added in sequence and reacted. Finally, 4,4'-difluorobenzophenone was added to continue the reaction. After precipitation, washing and drying, the reaction solution was used to obtain polyether ether ketone polymer.

2. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: In step (1), the molar ratio of hydroquinone, diphenyl sulfone and tetrabutyl titanate is (10-20):(100-130):(0.5-1).

3. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: In step (2), the molar ratio of diphenyl ether tetracarboxylic dianhydride, 3-amino-4-fluorophenol and potassium carbonate is 1:(2-2.5):(2-2.5).

4. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: The modified polyphenylene sulfide is prepared by the following process: Polyphenylene sulfide, acetyl chloride, and anhydrous ZnCl2 were added to a solvent and reacted to obtain acetylated polyphenylene sulfide. Then, under nitrogen protection, acetylated polyphenylene sulfide, diamino-terminated polydimethylsiloxane, p-toluenesulfonic acid, and anhydrous magnesium sulfate were mixed and reacted to obtain modified polyphenylene sulfide.

5. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: The compatibilizer is maleic anhydride-grafted polyethylene.

6. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: The wear-resistant agent is chopped aramid fiber.

7. The high-temperature and high-voltage resistant cable for new energy vehicles according to claim 1, characterized in that: The antioxidant is a combination of antioxidant 1010 and antioxidant 168.

8. A method for preparing a high-temperature and high-voltage resistant cable for new energy vehicles according to any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Twist multiple metal wires into a conductor, and spirally wrap mica tape around the conductor to obtain the cable core; Step 2: Use an extruder to extrude an insulation layer onto the surface of the cable core; Step 3: Use an extruder to extrude a sheath layer onto the surface of the insulation layer to prepare the cable.

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