A high temperature resistant composite material and its preparation method and application

Abstract

The present invention relates to the field of motor thermal insulation technology, and specifically to a high-temperature resistant composite material, a preparation method thereof, and an application thereof. The raw materials for preparing the high-temperature resistant 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, 24-36 parts of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 10-15 parts of nano-silica, 8-15 parts of (3-chloropropyl)triethoxysilane, and 20-30 parts of anhydrous potassium carbonate; the obtained high-temperature resistant composite material has low thermal conductivity, high thermal stability, and strong thermal insulation.

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 operating under high load, automotive motors generate localized high temperatures, reaching 200-400°C. Prolonged high temperatures can damage the motor wrapping, necessitating the use of high-temperature-resistant materials for localized insulation. These materials must meet high-temperature resistance and thermal insulation requirements to extend their service life. Existing automotive motor wrapping materials often use phenolic resins, which exhibit poor adhesion to the motor wrapping and easily release hazardous substances at high temperatures, making them less safe. Furthermore, some conventional insulation materials, such as fiber-reinforced aerogel insulation composites, while offering low thermal conductivity and excellent insulation performance, require improvement in strength and high-temperature resistance. Fiber-porous ceramic insulation materials offer good high-temperature resistance and moderate strength, but their thermal conductivity is relatively high. Fiber-reinforced oxide ceramic matrix composites offer high strength and good temperature resistance, but their thermal conductivity needs to be further reduced. With technological advancements, the demand for high-temperature-resistant composite materials for automotive motor insulation is increasing. A single material often struggles to meet the diverse performance requirements for automotive motor insulation, leading to the development of composite insulation materials. By combining 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:

[0005] A high-temperature resistant composite material is prepared from raw materials comprising 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-silica, 8-15 parts of (3-chloropropyl)triethoxysilane, and 20-30 parts of anhydrous potassium carbonate.

[0006] Furthermore, the mineral fiber includes any one of rock wool and glass wool.

[0007] Furthermore, the isocyanate includes any one of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and toluene diisocyanate (TDI).

[0008] Furthermore, the preparation method of the high temperature resistant composite material comprises the following steps:

[0009] S1: Preparation of modified mineral fibers:

[0010] S11: Add mineral fiber to toluene, sonicate at 300 W for 10 min, add isocyanate and stannous octoate, sonicate at 300 W for 10 min, react at 80°C for 4-5 h, wash with toluene, and dry in vacuum;

[0011] S12: adding the vacuum-dried product of step S11 to toluene, ultrasonically treating at 300-400 W for 10 min, adding caprolactam and stannous octoate, ultrasonically treating at 300-400 W for 10 min, reacting at 80° C. for 6-8 h, washing with toluene, and vacuum drying to obtain pretreated mineral fibers;

[0012] S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane were added to a reactor containing NMP, and ultrasonicated at 300W for 30 min. 3,3',4,4'-biphenyltetracarboxylic dianhydride was added in batches, with the addition amount of each batch being 25wt% and the time interval being 25-35 min. After the addition was completed, the reaction was carried out at room temperature for 8-10 h, the temperature was raised to 80°C and kept for 1 h, the temperature was raised to 150°C and kept for 6-8 h, the temperature was cooled, washed with NMP, and dried to obtain modified mineral fiber;

[0013] S2: Preparation of modified silica:

[0014] S21: Adjust the pH of anhydrous 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 minutes, and let stand for 1 hour;

[0015] S22: Add nano-silica to the solution after standing in step S21, stir magnetically for 10-15 minutes, stir in a water bath at 300 rpm and 80°C for 3-4 hours, cool to room temperature, filter, wash the filter cake with ethanol, and vacuum dry to obtain modified silica;

[0016] S3: Under a nitrogen atmosphere, modified mineral fiber, modified silica and anhydrous potassium carbonate were added to DMAc, heated and refluxed at 160°C until no water was taken out, kept at 160°C for 3-4 hours, added to a mold with an aluminum foil on the bottom, hot pressed at 2 MPa and 250°C for 1-2 minutes, and dried at 80-100°C to obtain a high-temperature resistant composite material.

[0017] Furthermore, in step S11, the mass concentration of the isocyanate in toluene is 20-25 mg / mL.

[0018] Furthermore, in step S11 and step S12, the amount of stannous octoate added is 0.6-0.8 wt % of the isocyanate, respectively.

[0019] Furthermore, in step S12, the mass concentration of the caprolactam in toluene is 20-25 mg / mL.

[0020] Furthermore, in step S13, the mass concentration of the 3,3',4,4'-biphenyltetracarboxylic dianhydride in NMP is 80-100 mg / mL.

[0021] Furthermore, in step S3, the mass concentration of the anhydrous potassium carbonate in DMAc is 40-50 mg / mL.

[0022] Furthermore, the present invention also provides application of the high-temperature resistant composite material in motor wrapping.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 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. The motor temperature of new energy vehicle motors may reach 300-400°C during practical use. Long-term high temperature will cause damage to the motor wrapping. The high-temperature resistant composite material of the present invention can effectively perform local thermal insulation. The present invention uses mineral fiber as a base material, which has good high-temperature resistance and provides basic heat resistance for the composite material. Through means such as mineral fiber surface modification, polyimide polymer design, and nano-silica modification, the stability of the material in high-temperature environments is achieved and the thermal insulation performance is improved. The present invention adopts mineral fiber as a skeleton material, and its three-dimensional network structure forms a stable support at high temperature. The hydroxyl group on the fiber surface reacts with isocyanate, and the reinforcing phase is anchored by a covalent bond. The isocyanate is introduced as a cross-linking agent, which significantly enhances the binding affinity between the mineral fiber and the subsequently added raw materials. The -NCO group thereof first reacts with the hydroxyl group on the surface of the mineral fiber to form a prepolymer, and then undergoes a grafting reaction with the subsequently added caprolactam to perform caprolactam end-capping modification, thereby improving the compatibility of the mineral fiber with the polyimide, and copolymerizing with 3,3',4,4'-biphenyltetracarboxylic dianhydride and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. 3,3',4,4'-biphenyltetracarboxylic dianhydride is used as an anhydride monomer, and is reacted with 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. The invention relates to a novel fluorinated polyimide (SF6) polymerized with hexafluoropropane (HFPA) and modified with polyimide monomers. The polyimide is connected to mineral fibers via caprolactam and isocyanate to form a three-dimensional cross-linked structure. This reduces molecular chain slippage at high temperatures and inhibits thermal motion of the molecular chains. Biphenyltetracarboxylic dianhydride provides a rigid biphenyl structure, enhancing the thermal stability of the molecular chains. The hexafluoropropane group introduces fluorine atoms, which enhances the thermal stability of the molecular chains through the high bond energy of the C-F bond and inhibits high-temperature degradation. The Si-C bond in SIDA has higher stability at high temperatures. In the fluorinated polyimide system, the synergistic effect of the hexafluoropropane group can further inhibit thermal degradation. The invention constructs a special polymer structure, greatly improving the upper limit of the high-temperature resistance of the material, making its performance lasting and stable at high temperatures. The present invention uses hydrolysis and condensation of (3-chloropropyl)triethoxysilane under acidic conditions to graft chloropropyl groups onto the surface of SiO2, effectively increasing the dispersibility of SiO2 in the resin matrix and improving interfacial compatibility. The introduction of modified silica significantly enhances the material's mechanical properties and improves its high-temperature resistance. In the preparation of polyimide, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane is used as a monomer. Phenolic hydroxyl groups are introduced into modified mineral fibers, which then covalently bond with the chlorine atoms of the modified nanosilica under the catalysis of potassium carbonate to form a cross-linked structure that fills the matrix. The physical constraint effect suppresses thermal motion of the matrix molecular chains, enhancing high-temperature resistance. The resulting high-temperature resistant composite thermal insulation material has promising application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is the thermal conductivity of the composite materials described in Examples 1-3 and Comparative Examples 1-3 of the present invention;

[0027] Figure 2 The high temperature stability of the composite materials described in Example 1 and Comparative Examples 1-3 of the present invention;

[0028] Figure 3 The thermal insulation performance of the high temperature materials described in Example 1 and Comparative Examples 1-3 of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific examples, but the present invention is not limited to the following examples. It should be noted that, unless otherwise specified, the chemical reagents involved in the present invention were purchased through commercial channels.

[0030] Example 1: A high-temperature resistant composite material, prepared by raw materials including 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.

[0031] A method for preparing a high-temperature resistant composite material comprises the following steps:

[0032] S1: Preparation of modified mineral fibers:

[0033] S11: Add 30 g of glass wool to 200 mL of toluene, sonicate at 300 W for 10 min, add 5 g of HDI and 40 mg of stannous octoate, sonicate at 300 W for 10 min, react at 80°C for 5 h, wash with toluene, and dry in vacuum.

[0034] S12: The product after vacuum drying in step S11 was added to 160 mL of toluene, and ultrasonicated at 400 W for 10 min. 4 g of caprolactam and 40 mg of stannous octoate were added, and ultrasonicated at 400 W for 10 min. The product was reacted at 80° C. for 8 h, washed with toluene, and vacuum dried to obtain pretreated mineral fibers.

[0035] S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 36 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane were added to a reactor containing 300 mL of NMP, and ultrasonicated at 300 W for 30 min. 3,3',4,4'-biphenyltetracarboxylic dianhydride was added in batches, with the addition amount of each batch being 25 wt% and the time interval being 35 min. After the addition was completed, the reaction was carried out at room temperature for 10 h, the temperature was raised to 80° C. and kept warm for 1 h, the temperature was raised to 150° C. and kept warm for 8 h, the temperature was cooled, washed with NMP, and dried to obtain modified mineral fiber;

[0036] S2: Preparation of modified silica:

[0037] S21: Adjust the pH of anhydrous ethanol to 4 with 10 wt% citric acid solution, add 15 g of (3-chloropropyl)triethoxysilane to a concentration of 3 v / v%, stir magnetically for 5 min, and let stand for 1 h;

[0038] S22: Add 15 g of nano-silica to the solution after standing in step S21, stir under magnetic stirring for 15 min, stir in a water bath at 300 rpm and 80°C for 4 h, cool to room temperature, filter, wash the filter cake with ethanol, and vacuum dry to obtain modified silica;

[0039] S3: Under a nitrogen atmosphere, modified mineral fiber, modified silica and 30 g of anhydrous potassium carbonate were added to 600 mL of DMAc, heated under reflux at 160°C until no water was taken out, kept at 160°C for 4 h, added to a mold with aluminum foil on the bottom, hot pressed at 2 MPa and 250°C for 2 min, and dried at 100°C to obtain a high-temperature resistant composite material.

[0040] Example 2: A high-temperature resistant composite material, prepared by raw materials including 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, and 20 parts of anhydrous potassium carbonate.

[0041] A method for preparing a high-temperature resistant composite material comprises the following steps:

[0042] S1: Preparation of modified mineral fibers:

[0043] S11: Add 20 g of rock wool to 150 mL of toluene, sonicate at 300 W for 10 min, add 3 g of IPDI and 18 mg of stannous octoate, sonicate at 300 W for 10 min, react at 80°C for 4 h, wash with toluene, and dry in vacuum.

[0044] S12: The vacuum-dried product of step S11 was added to 100 mL of toluene, and ultrasonicated at 300 W for 10 min. 2 g of caprolactam and 18 mg of stannous octoate were added, and ultrasonicated at 300 W for 10 min. The mixture was reacted at 80° C. for 6 h, washed with toluene, and vacuum-dried to obtain pretreated mineral fibers.

[0045] S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 24 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane were added to a reactor containing 250 mL of NMP, and ultrasonicated at 300 W for 30 min. 20 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added in batches, with the addition amount of each batch being 25 wt% and the time interval being 25 min. After the addition was completed, the reaction was carried out at room temperature for 8 h, the temperature was raised to 80° C. and kept warm for 1 h, the temperature was raised to 150° C. and kept warm for 6 h, the temperature was cooled, washed with NMP, and dried to obtain modified mineral fiber;

[0046] S2: Preparation of modified silica:

[0047] S21: Adjust the pH of anhydrous ethanol to 3 with 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;

[0048] S22: Add 10 g of nano-silica to the solution after standing in step S21, stir under magnetic stirring for 10 min, stir in a water bath at 300 rpm and 80°C for 3 h, cool to room temperature, filter, wash the filter cake with ethanol, and vacuum dry to obtain modified silica;

[0049] S3: Under a nitrogen atmosphere, modified mineral fiber, modified silica and 20 g of anhydrous potassium carbonate were added to 500 mL of DMAc, heated under reflux at 160°C until no water was taken out, kept at 160°C for 3 h, added to a mold with an aluminum foil on the bottom, hot pressed at 2 MPa and 250°C for 1 min, and dried at 80°C to obtain a high-temperature resistant composite material.

[0050] Example 3: A high-temperature resistant composite material, prepared by raw materials including 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, and 25 parts of anhydrous potassium carbonate.

[0051] A method for preparing a high-temperature resistant composite material comprises the following steps:

[0052] S1: Preparation of modified mineral fibers:

[0053] S11: Add 25 g of glass wool to 180 mL of toluene, sonicate at 300 W for 10 min, add 4 g of TDI and 28 mg of stannous octoate, sonicate at 300 W for 10 min, react at 80°C for 4.5 h, wash with toluene, and dry in vacuum.

[0054] S12: The product after vacuum drying in step S11 was added to 130 mL of toluene, and ultrasonicated at 350 W for 10 min. 3 g of caprolactam and 28 mg of stannous octoate were added, and ultrasonicated at 350 W for 10 min. The reaction was carried out at 80° C. for 7 h, and the product was washed with toluene and vacuum dried to obtain pretreated mineral fibers.

[0055] S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 30 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane were added to a reactor containing 300 mL of NMP, and ultrasonicated at 300 W for 30 min. 25 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added in batches, with the addition amount of each batch being 25 wt% and the time interval being 30 min. After the addition was completed, the reaction was carried out at room temperature for 9 h, the temperature was raised to 80° C. and kept warm for 1 h, the temperature was raised to 150° C. and kept warm for 7 h, the mixture was cooled, washed with NMP, and dried to obtain modified mineral fiber;

[0056] S2: Preparation of modified silica:

[0057] S21: Adjust the pH of anhydrous ethanol to 3.5 with 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;

[0058] S22: Add 12 g of nano-silica to the solution after standing in step S21, stir under magnetic stirring for 12 min, stir in a water bath at 300 rpm and 80°C for 3.5 h, cool to room temperature, filter, wash the filter cake with ethanol, and vacuum dry to obtain modified silica;

[0059] S3: Under a nitrogen atmosphere, modified mineral fiber, modified silica and 25 g of anhydrous potassium carbonate were added to 550 mL of DMAc, heated under reflux at 160°C until no water was taken out, kept at 160°C for 3.5 h, added to a mold with an aluminum foil on the bottom, hot pressed at 2 MPa and 250°C for 1.5 min, and dried at 90°C to obtain a high-temperature resistant composite material.

[0060] The only difference between Comparative Example 1 and Example 1 is that the modified mineral fiber is replaced by mineral fiber.

[0061] The only difference between Comparative Example 2 and Example 1 is that no modified silicon dioxide is added.

[0062] The only difference between Comparative Example 3 and Example 1 is that 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane is replaced by 2,2′-bis(trifluoromethyl)diaminobiphenyl.

[0063] Experimental Example 1: The high temperature resistant composite materials of Examples 1-3 and Comparative Examples 1-3 were measured for thermal conductivity using a thermal conductivity meter. The results are as follows: Figure 1 shown.

[0064] The smaller the thermal conductivity of the material, the better the thermal insulation effect. Figure 1 It can be seen from the results that the thermal conductivity of the high-temperature resistant composite materials prepared in Examples 1-3 and Comparative Examples 1-3 is small, the heat transfer capacity is poor, and the thermal insulation performance is good, which can be used for thermal insulation of motors. Among them, the thermal conductivity of Examples 1-3 is the smallest. Comparative Example 1 does not modify the mineral fiber and lacks polyimide modification, so the thermal conductivity increases and the thermal insulation effect decreases. Comparative Example 2 does not add sensitive silica, and the thermal conductivity increases. Comparative Example 3 replaces 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and the thermal conductivity increases, but the thermal insulation effect decreases.

[0065] Experimental Example 2: The high temperature resistant composite materials prepared in Example 1 and Comparative Examples 1-3 were heated from 30°C to 800°C at a rate of 10°C / min using a thermogravimetric analyzer in a nitrogen atmosphere to measure the initial decomposition temperature T d,5% (℃) and the retention rate R at 800℃ 800 (%), the thermal stability of high temperature resistant composite materials was determined. The results are as follows Figure 2 shown.

[0066] Figure 2 The results show that the initial decomposition temperature and the residual rate at 800°C in Example 1 were higher than those in Comparative Examples 1-3. Comparative Example 1 did not modify the mineral fiber and lacked polyimide modification, resulting in reduced thermal stability. Comparative Example 2 did not add modified silica, resulting in reduced heat resistance. Comparative Example 3 replaced 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, resulting in reduced thermal stability and high-temperature resistance. The high-temperature resistant composite material prepared by the present invention has excellent thermal stability, does not decompose at a motor surface temperature of 300°C, and does not produce odor, smoke, or open flames, meeting the motor insulation requirements.

[0067] Experimental Example 3: The performance of the high temperature resistant composite materials prepared in Example 1 and Comparative Examples 1-3 was tested using a hot plate as a heating instrument. The hot plate was heated to 300°C, and the sample was placed in the center of the hot plate and heated for 30 minutes. Finally, the top surface temperature was recorded using an infrared thermal imager. The results are as follows: Figure 3 shown.

[0068] Figure 3The results show that the upper surface temperature of Example 1 is lower than that of Comparative Examples 1-3. Comparative Example 1 does not modify the mineral fiber and lacks polyimide modification, resulting in reduced thermal insulation. Comparative Example 2 does not add modified silica, resulting in reduced thermal insulation. Comparative Example 3 replaces 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, resulting in reduced thermal insulation and thermal insulation performance. The high-temperature resistant composite material produced by the present invention has excellent thermal insulation properties and can be effectively used for motor wrapping.

[0069] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

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 preparation method of 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 to toluene, performing sonication, adding caprolactam and stannous octoate, performing sonication, reacting, washing, and drying to obtain pretreated mineral fibers; S13: Under a nitrogen atmosphere, the pretreated mineral fiber obtained in step S12 and 6FAP were added to NMP, ultrasonicated, BPDA was 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: Add nano-silica to the solution after standing in step S21, stir, stir in a water bath, cool, filter, wash the filter cake, and dry to obtain modified silica; S3: Under 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 an 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 amount of stannous octoate added is 0.6-0.8 wt % of the isocyanate.

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.

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