Wear-resistant enameled copper wire and preparation method thereof

Abstract

The invention provides a wear-resistant enameled copper wire and a preparation method thereof, and belongs to the technical field of enameled copper wires, and the preparation method comprises the following steps: coating a copper wire with wear-resistant paint for many times, curing to form a paint film, cooling, and taking up; the preparation method of the wear-resistant paint comprises the following steps: adding 4, 4 '-diamino-4' '-hydroxytriphenylmethane and 2, 2-bis-[4-(4-aminophenoxy) phenyl] propane into a polymerization bottle, then adding N, N-dimethylacetamide, stirring and dissolving, then adding 3, 3', 4, 4 '-benzophenonetetracarboxylic dianhydride, stirring and polymerizing to obtain a polyamide acid solution I; 4, 4 '-diaminodiphenyl ether is added into a polymerization bottle, then N, N-dimethylacetamide is added and stirred to be dissolved, then pyromellitic dianhydride is added and stirred to be polymerized, and a polyamide acid solution II is obtained; adding the polyamic acid solution I and the polyamic acid solution II into a polymerization bottle, then adding a silane coupling agent, stirring, then adding N, N-dimethylacetamide and a peroxide initiator, and uniformly stirring, so as to obtain the product. The wear resistance can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of enameled copper wires, and particularly relates to a wear-resistant enameled copper wire and a preparation method thereof. Background Art

[0002] Enameled wire is an important "electrical insulation material", which is prepared by coating a polymer insulating paint on metal wires such as copper, aluminum, and manganin alloy according to a specific production process, and this specific insulating paint is enameled wire paint. Enameled wire is mainly used as winding coils, and its function is to achieve the conversion of "electric" and "magnetic" energy during the operation of components. The insulating layer (i.e., the enameled wire film) coated on the enameled wire should have good thermal, electrical, mechanical, and chemical resistance properties.

[0003] Enameled wire is mainly used in electronics, electrical engineering, and electrical equipment, such as motors, household appliances, and electronic instruments. In some specific application scenarios, special specifications of enameled wire are required. For example, for walkmans, electronic watches, micro capacitors, electronic instruments, and palm computers, thinner enameled wire is needed; for artificial heart pacemakers, speaker voice coils, and microwave transformers, lighter enameled wire is required; for buzzers, micro electrical appliances, electronic transformers, and color TV deflectors, self-adhesive enameled wire is needed. With the rapid development of industry, the fields of electronics, electrical appliances, and electrical engineering have developed rapidly, and almost all equipment, instruments, and meters related to electricity are inseparable from enameled wire. Therefore, enameled wire paint is an irreplaceable industrial material.

[0004] In existing practical applications, the motors of new energy vehicles need to operate under high rotational speeds (>10,000 rpm) and frequent start-stop conditions. The enameled wire windings bear dynamic stress, and the surface film is prone to local peeling due to friction, affecting the insulation performance; wind turbines operate under strong wind loads and temperature differences (-40°C to 120°C) for a long time, and the enameled wire rubs against the stator slot wall at high frequencies, easily generating microcracks; industrial motors (such as machine tool spindle motors) operate under high dynamic loads and continuous vibration conditions, and the friction between the enameled wire and the core slot opening is intensified, resulting in an increased risk of film wear failure. It can be seen that in scenarios such as new energy vehicle drive motors, wind power generation sets, industrial high-speed equipment, high-frequency transformers, aerospace wire harnesses, and smart grid high-frequency cables, due to dynamic mechanical stress, high-frequency vibration, or extreme environmental effects, the requirement for wear resistance is particularly prominent. Therefore, improving wear resistance is a topic worthy of continuous research. Summary of the Invention

[0005] To solve the problems in the background art, the present invention provides a wear-resistant enameled copper wire and a preparation method thereof, which can effectively improve wear resistance.

[0006] To achieve the above object, in a first aspect, the present invention provides a method for preparing a wear-resistant enamelled copper wire, which is obtained by repeatedly coating a wear-resistant paint on a copper wire and curing it into a paint film, followed by cooling and winding; the method for preparing the wear-resistant paint is as follows:

[0007] S1. Add 4,4'-diamino-4"-hydroxytriphenylmethane and 2,2-bis-[4-(4-aminophenoxy)phenyl]propane into a polymerization flask, then add N,N-dimethylacetamide, stir and dissolve completely at room temperature, then add 3,3',4,4'-benzophenone tetracarboxylic dianhydride, and stir and polymerize in an ice-water bath for 3 - 3.5 h to obtain a polyamic acid solution I with a solid content of 20 - 22%;

[0008] S2. Add 4,4'-diaminodiphenyl ether into a polymerization flask, then add N,N-dimethylacetamide, stir and dissolve completely at room temperature, then add pyromellitic dianhydride, and stir and polymerize in an ice-water bath for 7.5 - 8 h to obtain a polyamic acid solution II with a solid content of 27 - 30%;

[0009] S3. Add the polyamic acid solution I obtained in S1 and the polyamic acid solution II obtained in S2 into a polymerization flask to obtain a polyamic acid mixed solution, then add a silane coupling agent, stir at room temperature, then add N,N-dimethylacetamide and a peroxide initiator, and stir evenly to obtain the wear-resistant paint; the silane coupling agent contains acryloyloxy groups.

[0010] Further, in S1, the molar ratio of 4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane and 3,3',4,4'-benzophenone tetracarboxylic dianhydride is 0.5:0.5:(1 - 1.05).

[0011] Further, in S2, the molar ratio of 4,4'-diaminodiphenyl ether and pyromellitic dianhydride is 1:(1 - 1.05).

[0012] Further, in S3, the mass ratio of the polyamic acid solution I to the polyamic acid solution II is (3 - 3.5):1.

[0013] Further, in S3, the mass of the silane coupling agent is 5 - 7% of the mass of the polyamic acid solution I.

[0014] Further, the silane coupling agent is γ-methacryloyloxypropyltrimethoxysilane.

[0015] Further, the mass of the peroxide initiator is 2 - 3% of the mass of the silane coupling agent.

[0016] Further, the peroxide initiator includes dicumyl peroxide or benzoyl peroxide.

[0017] Further, the solid content of the wear-resistant paint is 15-18%.

[0018] In a second aspect, the present invention provides a wear-resistant enamelled copper wire prepared by the above preparation method.

[0019] This application has the following beneficial effects:

[0020] In the present invention, diamines (4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane) and dianhydrides (3,3',4,4'-benzophenone tetracarboxylic dianhydride) undergo stepwise polymerization in a polar solvent (N,N-dimethylacetamide) to form polyamic acid I, which mainly contains hydroxyl groups (the side-chain hydroxyl groups of 4,4'-diamino-4"-hydroxytriphenylmethane are directly introduced into the polymer) and flexible chain segments (the ether bonds and propane spacer groups of 2,2-bis-[4-(4-aminophenoxy)phenyl]propane endow flexibility to the main chain);

[0021] Both 4,4'-diaminodiphenyl ether and pyromellitic dianhydride are aromatic monomers, which undergo stepwise polymerization in a polar solvent (N,N-dimethylacetamide) to form polyamic acid II. After polycondensation, the main chain is composed of continuous benzene rings and amide bonds, forming a rigid rod-like structure. The π-π conjugation of the benzene rings and the resonance effect of the amide bonds synergistically enhance the chain segment rigidity, making polyamic acid II mainly contain rigid chain segments;

[0022] When the mass ratio of polyamic acid solution I to polyamic acid solution II is (3-3.5):1, there are enough flexible chain segments for γ-methacryloxypropyltrimethoxysilane to bond and form a polyacrylate structure with a high crosslinking density during the subsequent curing process, fixing the molecular chain conformation, inhibiting the chain segment movement through steric hindrance effects, increasing the proportion of rigid (ified) chain segments, and thus synergistically improving the wear resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A comparative trend chart of the wear amount (g) test data of the enamelled copper wires prepared in Examples 1-3 and Comparative Examples 1-5 in the test example of the present invention under the test environment (temperature 25±2°C, humidity 50±5%) and test conditions (700 g load / 300 revolutions). DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following further elaborates on this application with reference to the embodiments.

[0025] The raw materials in the examples and comparative examples of this application are all commercially available as normal, unless otherwise specified.

[0026] Example 1: (1) Preparation of wear-resistant paint, and its preparation method is as follows:

[0027] S1. Add 4,4'-diamino-4"-hydroxytriphenylmethane and 2,2-bis-[4-(4-aminophenoxy)phenyl]propane into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add 3,3',4,4'-benzophenonetetracarboxylic dianhydride, and stir and polymerize uniformly at a stirring speed of 150 r / min in an ice-water bath for 3.2 h to obtain the first polyamic acid solution with a solid content of 21%. Among them, the molar ratio of 4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane and 3,3',4,4'-benzophenonetetracarboxylic dianhydride is 0.5:0.5:1.03.

[0028] S2. Add 4,4'-diaminodiphenyl ether into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add pyromellitic dianhydride, and stir and polymerize uniformly at a stirring speed of 150 r / min in an ice-water bath for 7.8 h to obtain the second polyamic acid solution with a solid content of 28%. Among them, the molar ratio of 4,4'-diaminodiphenyl ether and pyromellitic dianhydride is 1:1.03.

[0029] S3. Add the first polyamic acid solution obtained in S1 and the second polyamic acid solution obtained in S2 into a polymerization flask according to a mass ratio of 3.3:1, stir uniformly at 200 r / min for 10 min to ensure that the two solutions are fully miscible to obtain a polyamic acid mixed solution; then add γ-methacryloyloxypropyltrimethoxysilane, and its mass is 6% of the mass of the first polyamic acid solution. Stir at room temperature, increase the stirring speed to 320 r / min, and stir uniformly for 20 min to promote the bonding reaction between γ-methacryloyloxypropyltrimethoxysilane and hydroxyl groups; then add N,N-dimethylacetamide and diisopropylbenzene peroxide, and the mass of diisopropylbenzene peroxide is 2.5% of the mass of γ-methacryloyloxypropyltrimethoxysilane. Maintain the stirring speed of 320 r / min and stir for 10 min to stir evenly to ensure that the initiator is completely dissolved and uniformly dispersed, and the wear-resistant paint is obtained with a solid content of 16%.

[0030] (2) Prepare the wear-resistant enameled copper wire. The existing preparation method is as follows: After applying the wear-resistant paint on the copper wire multiple times and curing it into a paint film, then cooling and taking up the wire, the wear-resistant enameled copper wire is obtained.

[0031] Specifically, a large-capacity wire pay-off device is adopted, and the tension control system is used to ensure the smooth release of the copper wire, avoiding the wire being thinned or jittered due to uneven tension. The tension is controlled below 50% of the yield strength of the copper wire material. The inert gas protection annealing furnace is used for annealing treatment at about 450°C (12 seconds corresponding to a wire diameter of 0.1 mm), eliminating the cold working hardening of the copper wire, restoring its softness and removing the residual surface lubricant. After annealing, the surface of the copper wire is ultrasonically cleaned with deionized water to ensure no oil stain or oxide residue. Then, the wear-resistant paint prepared in (1) is coated by dipping. After each coating, preliminary curing is required. The total number of coating times is 5 times. The film thickness tolerance is ≤1 μm, and there are no bubbles or stripes on the surface. Then, it is baked and cured in sections, air-cooled, and wound up.

[0032] Example 2: The difference between this example and Example 1 is: (1) Preparation of the wear-resistant paint, and its preparation method is as follows:

[0033] S1. Add 4,4'-diamino-4"-hydroxytriphenylmethane and 2,2-bis-[4-(4-aminophenoxy)phenyl]propane into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add 3,3',4,4'-benzophenone tetracarboxylic dianhydride, and stir and polymerize in an ice-water bath for 3 h to obtain the first polyamic acid solution with a solid content of 20%. Among them, the molar ratio of 4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane and 3,3',4,4'-benzophenone tetracarboxylic dianhydride is 0.5:0.5:1.02.

[0034] S2. Add 4,4'-diaminodiphenyl ether into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add pyromellitic dianhydride, and stir and polymerize in an ice-water bath for 7.5 h to obtain the second polyamic acid solution with a solid content of 27%. Among them, the molar ratio of 4,4'-diaminodiphenyl ether and pyromellitic dianhydride is 1:1.02.

[0035] S3. Add the first polyamic acid solution obtained in S1 and the second polyamic acid solution obtained in S2 into a polymerization flask according to a mass ratio of 3:1 to obtain a polyamic acid mixed solution; then add γ-methacryloyloxypropyltrimethoxysilane, and its mass is 5% of the mass of the first polyamic acid solution, and stir at room temperature; then add N,N-dimethylacetamide and diisopropylbenzene peroxide, and the mass of diisopropylbenzene peroxide is 2% of the mass of γ-methacryloyloxypropyltrimethoxysilane, and stir evenly to obtain the wear-resistant paint with a solid content of 15%.

[0036] Example 3: The difference between this example and Example 1 is: (1) Preparation of the wear-resistant paint, and its preparation method is as follows:

[0037] S1. Add 4,4'-diamino-4"-hydroxytriphenylmethane and 2,2-bis-[4-(4-aminophenoxy)phenyl]propane into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add 3,3',4,4'-benzophenonetetracarboxylic dianhydride, and stir and polymerize in an ice-water bath for 3.5 h to obtain Polyamic acid solution I with a solid content of 22%. Among them, the molar ratio of 4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane and 3,3',4,4'-benzophenonetetracarboxylic dianhydride is 0.5:0.5:1.05.

[0038] S2. Add 4,4'-diaminodiphenyl ether into a polymerization flask, then add N,N-dimethylacetamide. After stirring and dissolving completely at room temperature, add pyromellitic dianhydride, and stir and polymerize in an ice-water bath for 8 h to obtain Polyamic acid solution II with a solid content of 30%. Among them, the molar ratio of 4,4'-diaminodiphenyl ether and pyromellitic dianhydride is 1:1.05.

[0039] S3. Add Polyamic acid solution I obtained in S1 and Polyamic acid solution II obtained in S2 into a polymerization flask according to a mass ratio of 3.5:1 to obtain a polyamic acid mixed solution; then add γ-methacryloxypropyltrimethoxysilane, and its mass is 7% of the mass of Polyamic acid solution I, and stir at room temperature; then add N,N-dimethylacetamide and diisopropylbenzene peroxide, and the mass of diisopropylbenzene peroxide is 3% of the mass of γ-methacryloxypropyltrimethoxysilane, and stir evenly to obtain a wear-resistant paint with a solid content of 18%.

[0040] Comparative Example 1: The difference between this comparative example and Example 1 is that γ-methacryloxypropyltrimethoxysilane and diisopropylbenzene peroxide are deleted; and the mass ratio of Polyamic acid solution I and Polyamic acid solution II is 2:1.

[0041] Specifically, in the preparation of the wear-resistant paint, in S3, add Polyamic acid solution I obtained in S1 and Polyamic acid solution II obtained in S2 into a polymerization flask according to a mass ratio of 2:1 to obtain a polyamic acid mixed solution; then add N,N-dimethylacetamide and stir evenly to obtain a wear-resistant paint with a solid content of 16%.

[0042] Comparative Example 2: The difference between this comparative example and Example 1 is that γ-methacryloxypropyltrimethoxysilane and diisopropylbenzene peroxide are deleted.

[0043] Specifically, in the preparation of the wear-resistant paint, in S3, add Polyamic acid solution I obtained in S1 and Polyamic acid solution II obtained in S2 into a polymerization flask according to a mass ratio of 3.3:1 to obtain a polyamic acid mixed solution; then add N,N-dimethylacetamide and stir evenly to obtain a wear-resistant paint with a solid content of 16%.

[0044] Comparative Example 3: The difference between this comparative example and Example 1 is that the mass ratio of polyamic acid solution one to polyamic acid solution two is 2:1.

[0045] Specifically, in the preparation of the wear-resistant paint, in S3, the polyamic acid solution one obtained in S1 and the polyamic acid solution two obtained in S2 are added to a polymerization flask at a mass ratio of 2:1 to obtain a polyamic acid mixed solution; then γ-methacryloyloxypropyltrimethoxysilane is added, and its mass is 6% of the mass of the polyamic acid solution one, and stirred at room temperature; then N,N-dimethylacetamide and diisopropylbenzene peroxide are added, and the mass of diisopropylbenzene peroxide is 2.5% of the mass of γ-methacryloyloxypropyltrimethoxysilane, and stirred evenly to obtain the wear-resistant paint, and its solid content is 16%.

[0046] Comparative Example 4: The difference between this comparative example and Example 1 is that diisopropylbenzene peroxide is deleted.

[0047] Specifically, in the preparation of the wear-resistant paint, in S3, the polyamic acid solution one obtained in S1 and the polyamic acid solution two obtained in S2 are added to a polymerization flask at a mass ratio of 3.3:1 to obtain a polyamic acid mixed solution; then γ-methacryloyloxypropyltrimethoxysilane is added, and its mass is 6% of the mass of the polyamic acid solution one, and stirred at room temperature; then N,N-dimethylacetamide is added and stirred evenly to obtain the wear-resistant paint, and its solid content is 16%.

[0048] Comparative Example 5: The difference between this comparative example and Example 1 is that γ-methacryloyloxypropyltrimethoxysilane is replaced by γ-aminopropyltriethoxysilane.

[0049] Specifically, in the preparation of the wear-resistant paint, in S3, the polyamic acid solution one obtained in S1 and the polyamic acid solution two obtained in S2 are added to a polymerization flask at a mass ratio of 3.3:1 to obtain a polyamic acid mixed solution; then γ-aminopropyltriethoxysilane is added, and its mass is 6% of the mass of the polyamic acid solution one, and stirred at room temperature; then N,N-dimethylacetamide and diisopropylbenzene peroxide are added, and the mass of diisopropylbenzene peroxide is 2.5% of the mass of γ-aminopropyltriethoxysilane, and stirred evenly to obtain the wear-resistant paint, and its solid content is 16%.

[0050] Test Example: Test object: The enameled copper wires prepared in Examples 1 - 3 and Comparative Examples 1 - 5.

[0051] Test items and methods: According to the conventional wear-resistant test standard for enameled wires (GB / T 6109 series), a reciprocating wear tester is used to test the wear amount (g) under the test environment (temperature 25 ± 2°C, humidity 50 ± 5%) and test conditions (700 g load / 300 revolutions); the smaller the wear amount value, the better the wear resistance.

[0052] Test results: See Table 1.

[0053] Table 1. Test data of test examples

[0054] Wear amount (g) Example 1 0.011 Example 2 0.013 Example 3 0.013 Comparative Example 1 0.018 Comparative Example 2 0.025 Comparative Example 3 0.021 Comparative Example 4 0.023 Comparative Example 5 0.022

[0055] Result analysis: Analyze Examples 1 - 3 and combine with the data in Table 1 and Figure 1 , it can be seen that the wear test data of the enameled copper wire prepared by the present invention (Examples 1 - 3) is as low as below 0.013 g under the test environment (temperature 25 ± 2 °C, humidity 50 ± 5%) and test conditions (700 g load / 300 revolutions), indicating that the enameled copper wire prepared by the present invention (Examples 1 - 3) has excellent wear resistance.

[0056] Analyze Example 1 and Comparative Examples 1 - 5 and combine with the data in Table 1 and Figure 1 , and the specific analysis is as follows:

[0057] By comparing Comparative Example 1 and Comparative Example 2, it can be known that compared with the mass ratio of polyamic acid solution one and polyamic acid solution two being 2:1 (Comparative Example 1), increasing the mass ratio of polyamic acid solution one and polyamic acid solution two to 3.3:1 (Comparative Example 2) will cause the wear resistance of the enameled copper wire prepared to decrease instead of increase. This is because the polymer in polyamic acid solution one mainly contains hydroxyl groups (-OH) and flexible chain segments, while the polymer in polyamic acid solution two mainly contains rigid chain segments. The flexible chain segments can absorb frictional energy through elastic deformation. However, once the proportion increases too much, it will lead to surface softening and increased wear, resulting in a decrease in wear resistance instead.

[0058] By comparing Comparative Example 1 and Comparative Example 3, it can be known that when the mass ratio of polyamic acid solution one and polyamic acid solution two is 2:1, compared with Comparative Example 1, γ-methacryloxypropyltrimethoxysilane and diisopropylbenzene peroxide are introduced in Comparative Example 3, and the result also causes the wear resistance of the enameled copper wire prepared to decrease instead of increase. This is because, on the one hand, the carboxylic acid groups (-COOH) in the polyamic acid mixed solution provide an acidic environment (pH ≈ 4 - 5), which can directly catalyze the condensation of methoxy groups (-OCH3) in γ-methacryloxypropyltrimethoxysilane with hydroxyl groups (-OH) on the surface of the flexible chain segments to form Si - O bonds, realizing chemical bonding; on the other hand, the rigid structural group acryloxy in γ-methacryloxypropyltrimethoxysilane forms a polyacrylate structure with a high crosslinking density during the subsequent curing process, fixing the molecular chain conformation and inhibiting the movement of chain segments through steric hindrance effects, making the chain segments rigid. When the mass ratio of polyamic acid solution one and polyamic acid solution two is 2:1, the proportion of flexible chain segments themselves is not high enough, and if they are rigidified (consumed) like this, the ability to absorb frictional energy will decrease too much, resulting in a decrease in wear resistance instead.

[0059] Combined with Example 1 for comparison, it can be seen that when the mass ratio of polyamic acid solution one to polyamic acid solution two is 3.3:1, introducing γ-methacryloyloxypropyltrimethoxysilane and diisopropylbenzene peroxide can synergistically improve the wear resistance of the enameled copper wire obtained. This is because when the mass ratio of polyamic acid solution one to polyamic acid solution two is 3.3:1, there are enough flexible chain segments for γ-methacryloyloxypropyltrimethoxysilane to combine (rigidification consumption), resulting in an increase in the proportion of rigid (ified) chain segments, thereby synergistically improving the wear resistance.

[0060] Combined with Comparative Example 4 - Comparative Example 5 for comparison, it can be seen that when the mass ratio of polyamic acid solution one to polyamic acid solution two is 3.3:1, deleting diisopropylbenzene peroxide or replacing γ-methacryloyloxypropyltrimethoxysilane with γ-aminopropyltriethoxysilane cannot achieve the synergistic improvement effect on wear resistance in Example 1. This is because if diisopropylbenzene peroxide is deleted, the rigid structural group acryloyloxy in γ-methacryloyloxypropyltrimethoxysilane cannot smoothly form a polyacrylate structure with a high crosslinking density during the subsequent curing process; if γ-methacryloyloxypropyltrimethoxysilane is replaced with γ-aminopropyltriethoxysilane, there is a lack of acryloyloxy that can self-polymerize, and it is impossible to smoothly increase the proportion of rigidified chain segments.

[0061] In addition, it should be noted that among the various specific technical features described in the above specific embodiments, without contradiction, they can be combined in any suitable way. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0062] Furthermore, any combination can be made between various different embodiments of the present invention, as long as it does not violate the idea of the present invention, it should also be regarded as the content disclosed by the present invention.

Claims

1. A method for preparing a wear-resistant enameled copper wire, comprising applying a wear-resistant varnish on the copper wire for multiple times and curing the varnish into a varnish film, followed by cooling and winding the wire; characterized in that: The preparation method of the wear-resistant paint is as follows: S1. Add 4,4'-diamino-4"-hydroxytriphenylmethane and 2,2-bis-[4-(4-aminophenoxy)phenyl]propane into a polymerization bottle, then add N,N-dimethylacetamide, stir and dissolve completely at room temperature, then add 3,3',4,4'-benzophenone tetracarboxylic dianhydride, stir and polymerize in an ice water bath for 3-3.5h to obtain a polyamic acid solution 1 with a solid content of 20-22%; S2, add 4,4'-diaminodiphenyl ether into a polymerization bottle, then add N,N-dimethylacetamide, stir and dissolve completely at room temperature, then add pyromellitic anhydride, stir and polymerize in an ice water bath for 7.5-8h to obtain polyamic acid solution II, whose solid content is 27-30%; S3, adding the polyamic acid solution 1 obtained in S1 and the polyamic acid solution 2 obtained in S2 into a polymerization bottle to obtain a polyamic acid mixed solution, then adding a silane coupling agent, stirring at room temperature, then adding N,N-dimethylacetamide and a peroxide initiator, stirring evenly, to obtain the wear-resistant paint.

2. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: In S1, the molar ratio of 4,4'-diamino-4"-hydroxytriphenylmethane, 2,2-bis-[4-(4-aminophenoxy)phenyl]propane and 3,3',4,4'-benzophenonetetracarboxylic dianhydride is 0.5:0.5:(1-1.05).

3. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: In S2, the molar ratio of 4,4'-diaminodiphenyl ether to pyromellitic dianhydride is 1:(1-1.05).

4. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: In S3, the mass ratio of the polyamic acid solution 1 to the polyamic acid solution 2 is (3-3.5):

1.

5. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: In S3, the mass of the silane coupling agent is 5-7% of the mass of the polyamic acid solution 1.

6. The method for preparing the wear-resistant enameled copper wire according to claim 1 or 5, characterized in that: The silane coupling agent is γ-methacryloxypropyltrimethoxysilane.

7. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: The mass of the peroxide initiator is 2-3% of the mass of the silane coupling agent.

8. The method for preparing the wear-resistant enameled copper wire according to claim 1 or 7, characterized in that: The peroxide initiator includes dicumyl peroxide or benzoyl peroxide.

9. The method for preparing the wear-resistant enameled copper wire according to claim 1, characterized in that: The solid content of the wear-resistant paint is 15-18%.

10. A wear-resistant enameled copper wire, characterized in that: The method is prepared according to any one of claims 1 to 9.

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