High-temperature-resistant composite material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of motor heat insulation, in particular to a high-temperature-resistant composite material and a preparation method and application thereof. The high-temperature-resistant composite material is prepared from the following raw materials in parts by weight: 20 to 30 parts of mineral fiber, 3 to 5 parts of isocyanate, 2 to 4 parts of caprolactam, 20 to 30 parts of 3, 3 ', 4, 4'-biphenyltetracarboxylic dianhydride, 24 to 36 parts of 2, 2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 10 to 15 parts of nano silicon dioxide, 8 to 15 parts of (3-chloropropyl) triethoxysilane and 20 to 30 parts of anhydrous potassium carbonate. The prepared high-temperature-resistant composite material is low in heat conductivity, high in heat stability and high in heat insulation property.

Description

Technical Field

[0001] The present invention relates to the technical field of motor thermal insulation, and in particular to a high temperature resistant composite material and a preparation method and application thereof. Background Art

[0002] When the automobile motor is running at high load, it will generate local high temperature, and the motor temperature can reach 200-400℃. Long-term high temperature will damage the motor package. Therefore, it is necessary to use high-temperature resistant materials for local heat insulation. The automobile motor package materials must meet the requirements of high temperature resistance and heat insulation performance to increase the service life of the motor package materials. Existing automobile motor package materials mostly use phenolic resin materials, which have poor fit with the motor package, and are easy to volatilize harmful substances under high temperature conditions, and have low safety; in addition, some traditional thermal insulation materials in the prior art, such as fiber-reinforced aerogel insulation composite materials, although they have low thermal conductivity and excellent thermal insulation performance, their strength and high temperature resistance need to be improved; fiber porous ceramic insulation materials have good high temperature resistance and certain strength, but their thermal conductivity is high; fiber-reinforced oxide ceramic-based composite materials have high strength and good temperature resistance, but the thermal conductivity also needs to be further reduced. With the development of technology, the requirements for high-temperature resistant composite materials used for automobile motor insulation are getting higher and higher. A single material is often difficult to meet the various performance requirements of automobile motor insulation, so composite insulation materials have become a development trend. By compounding materials with different properties, we can give full play to the advantages of each component material and obtain a composite material with better performance. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a high temperature resistant composite material and a preparation method and application thereof.

[0004] The present invention is achieved through the following technical solutions: A high-temperature resistant composite material, wherein the raw materials for preparing the composite material include the following components in parts by weight: 20-30 parts of mineral fiber, 3-5 parts of isocyanate, 2-4 parts of caprolactam, 20-30 parts of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 24-36 parts of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP), 10-15 parts of nano-silicon dioxide, 8-15 parts of (3-chloropropyl)triethoxysilane, and 20-30 parts of anhydrous potassium carbonate.

[0005] Furthermore, the mineral fiber includes any one of rock wool and glass wool.

[0006] Furthermore, the isocyanate includes any one of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and toluene diisocyanate (TDI).

[0007] Further, the preparation method of the high-temperature resistant composite material comprises the following steps: S1: Prepare modified mineral fiber: S11: Add mineral fiber into toluene, ultrasonicate at 300 W for 10 min, add isocyanate and stannous octoate, ultrasonicate at 300 W for 10 min, react at 80 °C for 4 - 5 h, wash with toluene, and dry under vacuum; S12: Add the product after vacuum drying in step S11 into toluene, ultrasonicate at 300 - 400 W for 10 min, add caprolactam and stannous octoate, ultrasonicate at 300 - 400 W for 10 min, react at 80 °C for 6 - 8 h, wash with toluene, and dry under vacuum to obtain pretreated mineral fiber; S13: Under a nitrogen atmosphere, take the pretreated mineral fiber obtained in step S12 and 2,2 - bis(3 - amino - 4 - hydroxyphenyl)hexafluoropropane and add them into a reaction kettle containing NMP, ultrasonicate at 300 W for 30 min, add 3,3',4,4'-biphenyltetracarboxylic dianhydride in batches, the feeding amount of each batch is 25 wt%, the time interval is 25 - 35 min, after the feeding is completed, react at room temperature for 8 - 10 h, raise the temperature to 80 °C and keep warm for 1 h, raise the temperature to 150 °C and keep warm for 6 - 8 h, cool, wash with NMP, and dry to obtain modified mineral fiber; S2: Prepare modified silica: S21: Adjust the pH of absolute ethanol to 3 - 4 with 10 wt% citric acid solution, add (3 - chloropropyl)triethoxysilane to a concentration of 2 - 3 v / v%, stir magnetically for 3 - 5 min, and let stand for 1 h; S22: Add nano - silica to the solution after standing in step S21, stir magnetically for 10 - 15 min, stir in a water bath at 300 r / min and 80 °C for 3 - 4 h, cool to room temperature, filter by suction, wash the filter cake with ethanol, and dry under vacuum to obtain modified silica; S3: Under a nitrogen atmosphere, add the modified mineral fiber, modified silica and anhydrous potassium carbonate into DMAc, heat - reflux at 160 °C until no water is carried out, keep warm at 160 °C for 3 - 4 h, add into a mold with aluminum foil laid at the bottom, hot - press at 2 MPa and 250 °C for 1 - 2 min, and dry at 80 - 100 °C to obtain the high - temperature resistant composite material.

[0008] Further, in step S11, the mass concentration of the isocyanate in toluene is 20 - 25 mg / mL.

[0009] Further, in steps S11 and S12, the addition amounts of stannous octoate are respectively 0.6 - 0.8 wt% of the isocyanate.

[0010] Further, in step S12, the mass concentration of caprolactam in toluene is 20 - 25 mg / mL.

[0011] Further, in step S13, the mass concentration of 3,3',4,4'-biphenyltetracarboxylic dianhydride in NMP is 80 - 100 mg / mL.

[0012] Further, in step S3, the mass concentration of anhydrous potassium carbonate in DMAc is 40 - 50 mg / mL.

[0013] Further, the present invention also provides an application of the high-temperature resistant composite material in motor wrapping.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a high-temperature resistant composite material, which significantly improves the high-temperature stability of the material through the synergistic effect of multiple components. During the practical use of the motor in new energy vehicles, the motor temperature may reach within the range of 300 - 400 °C, and the long-term high temperature may cause damage to the motor wrapping. The high-temperature resistant composite material of the present invention can effectively provide local heat insulation. The present invention uses mineral fiber as the base material, which has good high-temperature resistance characteristics and provides the basic heat resistance performance for the composite material. Through means such as surface modification of mineral fiber, design of polyimide polymer, and modification of nano-silica, the stability of the material in a high-temperature environment is achieved, and the heat insulation performance is improved. The present invention uses mineral fiber as the framework material, and its three-dimensional network structure forms a stable support at high temperature. The hydroxyl groups on the fiber surface react with isocyanate, and the reinforcing phase is anchored through covalent bonds. Isocyanate is introduced as a crosslinking agent, which significantly enhances the binding affinity between the mineral fiber and the subsequently added raw materials. Its -NCO group first reacts with the hydroxyl groups on the mineral fiber surface to form a prepolymer, and then undergoes a grafting reaction with the subsequently added caprolactam for caprolactam end-capping modification to improve the compatibility between the mineral fiber and polyimide. It copolymerizes with 3,3',4,4'-biphenyltetracarboxylic dianhydride and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. Using 3,3',4,4'-biphenyltetracarboxylic dianhydride as the acid anhydride monomer, it reacts with 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and polymerization modification is carried out using polyimide monomers. The polyimide is connected to the mineral fiber through caprolactam and isocyanate to form a three-dimensional crosslinked structure, reducing the molecular chain slippage at high temperature and inhibiting the molecular chain thermal motion. The biphenyltetracarboxylic dianhydride provides a rigid biphenyl structure to enhance the thermal stability of the molecular chain; the hexafluoropropyl group introduces fluorine atoms, and the high bond energy of the C-F bond enhances the thermal stability of the molecular chain and inhibits high-temperature degradation. The Si-C bond in SIDA has higher stability at high temperature. In the fluorinated polyimide system, the synergistic effect of the hexafluoropropyl group can further inhibit thermal degradation. The present invention constructs a special polymer structure, greatly improving the upper limit of the high-temperature resistance of the material and making its performance durable and stable at high temperature. The present invention hydrolyzes and condenses (3-chloropropyl)triethoxysilane under acidic conditions to graft chloropropyl groups on the 2 surface, effectively improving the dispersibility of SiO 2 in the resin matrix, improving the interfacial compatibility. The introduction of modified silica significantly enhances the mechanical properties of the material and improves the high-temperature resistance performance. In the preparation of polyimide, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane is used as a monomer to introduce phenolic hydroxyl groups on the modified mineral fiber, and covalently combines with the chlorine atoms of the modified nano-silica under the catalysis of potassium carbonate to form a crosslinked structure, filling the matrix, and inhibiting the molecular chain thermal motion of the matrix through the physical constraint effect, enhancing the high-temperature resistance performance. The high-temperature resistant composite heat insulation material prepared by the present invention has good application prospects. Description of the Drawings

[0015] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 Thermal conductivity of the composite materials described in Examples 1-3 and Comparative Examples 1-3 of the present invention; Figure 2 High-temperature stability of the composite materials described in Example 1 and Comparative Examples 1-3 of the present invention; Figure 3 Heat insulation performance of the high-temperature materials described in Example 1 and Comparative Examples 1-3 of the present invention. Detailed implementation manners

[0017] To make the objectives, technical solutions and advantages of the present invention more clearly understood, the following further details the present invention with reference to specific embodiments, but the present invention is not limited to the following embodiments. It should be noted that unless otherwise specified, the chemical reagents involved in the present invention are purchased through commercial channels.

[0018] Example 1: A high-temperature resistant composite material, the preparation raw materials include the following components in parts by weight: 30 parts of glass wool, 5 parts of HDI, 4 parts of caprolactam, 30 parts of 3,3',4,4'-biphenyltetracarboxylic dianhydride, 36 parts of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 15 parts of nano-silica, 15 parts of (3-chloropropyl)triethoxysilane, and 30 parts of anhydrous potassium carbonate.

[0019] Preparation method of the high-temperature resistant composite material, including the following steps: S1: Prepare modified mineral fiber: S11: Add 30 g of glass wool to 200 mL of toluene, ultrasonicate at 300 W for 10 min, add 5 g of HDI and 40 mg of stannous octoate, ultrasonicate at 300 W for 10 min, react at 80°C for 5 h, wash with toluene, and dry under vacuum; S12: Add the product after vacuum drying in step S11 to 160 mL of toluene, ultrasonicate at 400 W for 10 min, add 4 g of caprolactam and 40 mg of stannous octoate, ultrasonicate at 400 W for 10 min, react at 80°C for 8 h, wash with toluene, and dry under vacuum to obtain pretreated mineral fiber; S13: Under a nitrogen atmosphere, add the pretreated mineral fiber obtained in step S12 and 36 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane to a reaction kettle containing 300 mL of NMP, ultrasonically treat for 30 min at 300 W, add 30 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride in batches, with the feeding amount of each batch being 25 wt%, the time interval being 35 min. After the feeding is completed, react at room temperature for 10 h, raise the temperature to 80 °C and keep warm for 1 h, then raise the temperature to 150 °C and keep warm for 8 h, cool, wash with NMP, and dry to obtain the modified mineral fiber; S2: Prepare modified silica: S21: Adjust the pH of anhydrous ethanol to 4 with a 10 wt% citric acid solution, add 15 g of (3-chloropropyl)triethoxysilane to a concentration of 3 v / v%, magnetically stir for 5 min, and let stand for 1 h; S22: Add 15 g of nano-silica to the solution after standing in step S21, magnetically stir for 15 min, stir in a water bath at 80 °C at 300 r / min for 4 h, cool to room temperature, filter by suction, wash the filter cake with ethanol, and dry under vacuum to obtain the modified silica; S3: Under a nitrogen atmosphere, add the modified mineral fiber, modified silica and 30 g of anhydrous potassium carbonate to 600 mL of DMAc, heat and reflux at 160 °C until no water is carried out, keep warm at 160 °C for 4 h, add to a mold with aluminum foil laid at the bottom, hot press at 2 MPa and 250 °C for 2 min, and dry at 100 °C to obtain the high-temperature resistant composite material.

[0020] Example 2: A high-temperature resistant composite material, the preparation raw materials include the following components in parts by weight: 20 parts of rock wool, 3 parts of IPDI, 2 parts of caprolactam, 20 parts of 3,3',4,4'-biphenyltetracarboxylic dianhydride, 24 parts of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 10 parts of nano-silica, 8 parts of (3-chloropropyl)triethoxysilane, 20 parts of anhydrous potassium carbonate.

[0021] The preparation method of the high-temperature resistant composite material includes the following steps: S1: Prepare modified mineral fiber: S11: Add 20 g of rock wool to 150 mL of toluene, ultrasonically treat at 300 W for 10 min, add 3 g of IPDI and 18 mg of stannous octoate, ultrasonically treat at 300 W for 10 min, react at 80 °C for 4 h, wash with toluene, and dry under vacuum; S12: Add the product after vacuum drying in step S11 to 100 mL of toluene, ultrasonically treat at 300 W for 10 min, add 2 g of caprolactam and 18 mg of stannous octoate, ultrasonically treat at 300 W for 10 min, react at 80 °C for 6 h, wash with toluene, and dry under vacuum to obtain the pretreated mineral fiber; S13: Under a nitrogen atmosphere, take the pretreated mineral fiber obtained in step S12 and 24 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane and add them to a reaction kettle containing 250 mL of NMP. Ultrasonic at 300 W for 30 min, and add 20 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride in batches. The feeding amount of each batch is 25 wt%, and the time interval is 25 min. After the feeding is completed, react at room temperature for 8 h, heat up to 80 °C and keep warm for 1 h, then heat up to 150 °C and keep warm for 6 h, cool, wash with NMP, and dry to obtain modified mineral fiber; S2: Prepare modified silica: S21: Adjust the pH of anhydrous ethanol to 3 with a 10 wt% citric acid solution, add 8 g of (3-chloropropyl)triethoxysilane to a concentration of 2 v / v%, stir magnetically for 3 min, and let stand for 1 h; S22: Add 10 g of nano-silica to the solution after standing in step S21, stir magnetically for 10 min, stir in a water bath at 300 r / min and 80 °C for 3 h, cool to room temperature, filter by suction, wash the filter cake with ethanol, and dry in vacuum to obtain modified silica; S3: Under a nitrogen atmosphere, add the modified mineral fiber, modified silica and 20 g of anhydrous potassium carbonate to 500 mL of DMAc, heat and reflux at 160 °C until no water is carried out, keep warm at 160 °C for 3 h, add to a mold with aluminum foil laid at the bottom, hot press at 2 MPa and 250 °C for 1 min, and dry at 80 °C to obtain a high-temperature resistant composite material.

[0022] Example 3: A high-temperature resistant composite material, the preparation raw materials include the following components in parts by weight: 25 parts of glass wool, 4 parts of TDI, 3 parts of caprolactam, 25 parts of 3,3',4,4'-biphenyltetracarboxylic dianhydride, 30 parts of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 12 parts of nano-silica, 12 parts of (3-chloropropyl)triethoxysilane, 25 parts of anhydrous potassium carbonate.

[0023] A method for preparing a high-temperature resistant composite material, comprising the following steps: S1: Prepare modified mineral fiber: S11: Add 25 g of glass wool to 180 mL of toluene, ultrasonic at 300 W for 10 min, add 4 g of TDI and 28 mg of stannous octoate, ultrasonic at 300 W for 10 min, react at 80 °C for 4.5 h, wash with toluene, and dry in vacuum; S12: Add the product after vacuum drying in step S11 into 130 mL of toluene, ultrasonicate at 350 W for 10 min, add 3 g of caprolactam and 28 mg of stannous octoate, ultrasonicate at 350 W for 10 min, react at 80 °C for 7 h, wash with toluene, and vacuum dry to obtain pretreated mineral fibers; S13: Under a nitrogen atmosphere, take the pretreated mineral fibers obtained in step S12 and 30 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane and add them to a reaction kettle containing 300 mL of NMP, ultrasonicate at 300 W for 30 min, add 25 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride in batches, with the feeding amount of each batch being 25 wt%, the time interval being 30 min. After the feeding is completed, react at room temperature for 9 h, raise the temperature to 80 °C and keep warm for 1 h, then raise the temperature to 150 °C and keep warm for 7 h, cool, wash with NMP, and dry to obtain modified mineral fibers; S2: Prepare modified silica: S21: Adjust the pH of absolute ethanol to 3.5 with a 10 wt% citric acid solution, add 12 g of (3-chloropropyl)triethoxysilane to a concentration of 2.5 v / v%, stir magnetically for 4 min, and let stand for 1 h; S22: Add 12 g of nano-silica to the solution after standing in step S21, stir magnetically for 12 min, stir in a water bath at 300 r / min and 80 °C for 3.5 h, cool to room temperature, filter by suction, wash the filter cake with ethanol, and vacuum dry to obtain modified silica; S3: Under a nitrogen atmosphere, add the modified mineral fibers, modified silica, and 25 g of anhydrous potassium carbonate to 550 mL of DMAc, heat and reflux at 160 °C until no water is carried out, keep warm at 160 °C for 3.5 h, add to a mold with aluminum foil laid at the bottom, hot press at 2 MPa and 250 °C for 1.5 min, and dry at 90 °C to obtain a high-temperature resistant composite material.

[0024] The difference between Comparative Example 1 and Example 1 is only that the modified mineral fibers are replaced with mineral fibers.

[0025] The difference between Comparative Example 2 and Example 1 is only that the modified silica is not added.

[0026] The difference between Comparative Example 3 and Example 1 is only that 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane is replaced with 2,2'-bis(trifluoromethyl)diaminobiphenyl.

[0027] Experimental Example 1: Take the high-temperature resistant composite materials of Examples 1-3 and Comparative Examples 1-3, and use a thermal conductivity meter to measure the thermal conductivity. The results are as Figure 1 shown.

[0028] The smaller the thermal conductivity coefficient of the material, the better the heat insulation effect. FromFigure 1 As can be seen from the results, the thermal conductivity of the high-temperature resistant composite materials prepared in Examples 1-3 and Comparative Examples 1-3 is relatively small, the heat transfer ability is poor, and the heat insulation performance is good. They can be applied to the heat insulation of motors. Among them, the thermal conductivity of Examples 1-3 is the smallest. In Comparative Example 1, the mineral fiber was not modified and lacked polyimide modification, resulting in an increase in thermal conductivity and a decrease in heat insulation effect. In Comparative Example 2, no modified silica was added, resulting in an increase in thermal conductivity. In Comparative Example 3, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane was replaced, resulting in an increase in thermal conductivity and a decrease in heat insulation effect.

[0029] Experimental Example 2: The high-temperature resistant composite materials prepared in Example 1 and Comparative Examples 1-3 were taken, and under a nitrogen atmosphere, using a thermogravimetric analyzer, they were heated from 30°C to 800°C at a rate of 10°C / min to measure the initial decomposition temperature T d,5% (°C) and the residue ratio R 800 (%) at 800°C to measure the thermal stability of the high-temperature resistant composite materials. The results are as Figure 2 shown.

[0030] Figure 2 The results show that the initial decomposition temperature and the residue ratio at 800°C of the Example 1 group are higher than those of Comparative Examples 1-3. In Comparative Example 1, the mineral fiber was not modified and lacked polyimide modification, resulting in a decrease in thermal stability. In Comparative Example 2, no modified silica was added, resulting in a decrease in heat resistance. In Comparative Example 3, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane was replaced, resulting in a decrease in thermal stability and a decrease in high-temperature resistance. The high-temperature resistant composite material prepared by the present invention has good thermal stability and will not decompose at a motor surface temperature of 300°C, and will not produce peculiar smell, smoke, or open fire, meeting the motor heat insulation requirements.

[0031] Experimental Example 3: Using a hot stage as the heating instrument, the performance of the high-temperature resistant composite materials prepared in Example 1 and Comparative Examples 1-3 was tested. The hot stage was heated to 300°C, the sample was placed in the center of the hot stage and heated for 30 min, and finally the top surface temperature was recorded using an infrared thermal imager. The results are as Figure 3 shown.

[0032] Figure 3 The results show that the upper surface temperature of Example 1 is lower than that of Comparative Examples 1-3. In Comparative Example 1, the mineral fiber was not modified and lacked polyimide modification, resulting in a decrease in heat insulation. In Comparative Example 2, no modified silica was added, resulting in a decrease in heat insulation. In Comparative Example 3, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane was replaced, resulting in a decrease in heat insulation and a decrease in heat insulation performance. The high-temperature resistant composite material prepared by the present invention has good heat insulation performance and can effectively insulate when applied to motor wrapping.

[0033] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above, and they are not provided in detail for the sake of brevity.

Claims

1. A high temperature resistant composite material, characterized in that: The raw materials for preparation include the following components in parts by weight: 20-30 parts of mineral fiber, 3-5 parts of isocyanate, 2-4 parts of caprolactam, 20-30 parts of BPDA, 24-36 parts of 6FAP, 10-15 parts of nano-silicon dioxide, 8-15 parts of (3-chloropropyl)triethoxysilane, and 20-30 parts of anhydrous potassium carbonate; The method for preparing the high temperature resistant composite material comprises the following steps: S1: Preparation of modified mineral fibers: S11: adding mineral fiber to toluene, ultrasonicating, adding isocyanate and stannous octoate, ultrasonicating, reacting, washing, and vacuum drying; S12: adding the vacuum-dried product of step S11 into toluene, performing ultrasound, adding caprolactam and stannous octoate, performing ultrasound, reacting, washing, and drying to obtain pretreated mineral fibers; S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 6FAP are added to NMP, ultrasonicated, BPDA is added, reacted at room temperature, heated, cooled, washed, and dried to obtain modified mineral fiber; S2: Preparation of modified silica: S21: Adjust the pH of anhydrous ethanol to 3-4, add (3-chloropropyl)triethoxysilane, stir, and let stand; S22: adding nano-silicon dioxide to the solution after standing in step S21, stirring, stirring in a water bath, cooling, suction filtering, washing the filter cake, and drying to obtain modified silicon dioxide; S3: In a nitrogen atmosphere, the modified mineral fiber, modified silica and anhydrous potassium carbonate are added to DMAc, heated and refluxed until no water is taken out, kept warm, added to a mold with aluminum foil on the bottom, hot pressed, and dried to obtain a high temperature resistant composite material; The mineral fiber includes any one of rock wool and glass wool; the isocyanate includes any one of HDI, IPDI and TDI.

2. The high temperature resistant composite material according to claim 1, characterized in that: In step S11, the mass concentration of the isocyanate in toluene is 20-25 mg / mL.

3. The high temperature resistant composite material according to claim 2, characterized in that: In step S11 and step S12, the added amount of stannous octoate is 0.6-0.8 wt % of the isocyanate respectively.

4. The high temperature resistant composite material according to claim 3, characterized in that: In step S12, the mass concentration of caprolactam in toluene is 20-25 mg / mL.

5. The high temperature resistant composite material according to claim 4, characterized in that: In step S13, the mass concentration of BPDA in NMP is 80-100 mg / mL.

6. The high temperature resistant composite material according to claim 5, characterized in that: In step S3, the mass concentration of anhydrous potassium carbonate in DMAc is 40-50 mg / mL.

7. Use of the high temperature resistant composite material according to any one of claims 1 to 6 in motor wrapping.

Images