Insulated wire and preparation method thereof, coil and electronic / electrical equipment

Abstract

The invention discloses an insulated wire and a preparation method thereof, a coil and electronic / electrical equipment, the insulated wire comprises a conductor and an insulating layer arranged at the periphery of the conductor, the material of the insulating layer is obtained by mixing and granulating two resins, namely resin A and resin B, and the material obtained after mixing comprises units shown in the following formulas 1-3: # imgabs 0 # formula 1, # imgabs 1 # formula 2 and # imgabs 2 # formula 3; the molar ratio of the unit as shown in the formula 1 is 3-17%, the molar ratio of the unit as shown in the formula 2 is 37-77%, and the molar ratio of the unit as shown in the formula 3 is 20-47%. According to the invention, the adhesiveness of the pure PEEK resin and a copper conductor can be improved, and the flexibility of the insulating material is improved; and the PEK-C and the PEEK both belong to polyarylether ketones and have the same ether bond and ketone group, so that the compatibility of the PEK-C and the PEEK is good, and the overall strength and stability of the blended material can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of insulated wires, and more particularly to an insulated wire and a preparation method thereof, a coil and an electronic / electrical device. Background Art

[0002] At present, in the field of new energy vehicles, 800V high-voltage drive systems have become the first choice for new energy vehicles due to their efficient charging capabilities and excellent endurance performance. However, with the increase in voltage levels, the requirements for insulation materials have become more stringent. In high-voltage and high-temperature working environments, insulated wires must maintain their excellent insulation properties to ensure the safe and reliable operation of electrical systems.

[0003] In the prior art, polyetheretherketone (PEEK) is a resin with excellent electrical insulation performance, and its volume resistivity is about 10 15 -10 16 Ω·cm, it still has a low dielectric constant and small dielectric loss in the high frequency range. For example, at room temperature, 4 The dielectric constant at Hz is 3.2, and the dielectric loss is only 0.02. At the same time, this PEEK resin also has excellent heat resistance and mechanical properties as well as excellent chemical stability and excellent resistance to hot water and steam. Therefore, PEEK resin is an ideal insulation material for magnet wire.

[0004] However, PEEK resin is too resistant to chemical solvents and is insoluble in general organic solvents. It cannot be prepared into a coating for coating electromagnetic wires and can only be coated on the electromagnetic wires by high-temperature melt extrusion. However, the high melt viscosity and fast cooling rate of PEEK resin result in unstable adhesion between the PEEK resin coating and the copper surface of the electromagnetic wire, which often has the risk of falling off the tube and breaking; and the flexibility of PEEK resin is also poor. Summary of the invention

[0005] In view of this, one of the objectives of the present invention is to provide an insulated wire to improve the adhesion and flexibility of the insulating material in the prior art.

[0006] To achieve the above object, the technical solution of the present invention is as follows: An insulated wire comprises a conductor and an insulating layer arranged on the outer periphery of the conductor, wherein the insulating layer is made by mixing and granulating two resins, resin A and resin B, and the mixed material contains the units shown in the following formulas 1 to 3: Formula 1, Formula 2: Formula 3; Among them, the molar proportion of the unit shown in formula 1 is 3-17%, the molar proportion of the unit shown in formula 2 is 37-77%, and the molar proportion of the unit shown in formula 3 is 20-47%.

[0007] Furthermore, the crystallinity of the material is 15-26%.

[0008] Furthermore, the resin A is polyetheretherketone resin (PEEK).

[0009] Furthermore, the structural formula of the polyetheretherketone resin is shown in Formula 4 below:

[0010] Formula 4; Among them, m is 50~200.

[0011] Furthermore, the resin B is phenolphthalein polyaryletherketone resin (PEK-C).

[0012] Furthermore, the structural formula of the phenolphthalein polyaryletherketone resin is shown in Formula 5 below:

[0013] Formula 5; Wherein, n is 50-150, preferably 50-100.

[0014] Phenolphthalein polyaryletherketone (PEK-C), also known as phenolphthalein type polyaryletherketone, refers to a polymer material formed by connecting phenylene rings through ether bonds and carbonyl groups. Phenolphthalein polyaryletherketone has the advantages of high modulus, high strength, impact resistance, good thermal stability, good electrical insulation, corrosion resistance, and good dimensional stability. It is widely used in high-performance composite materials, water treatment, electronics and electrical, aerospace, automobile manufacturing, rail transportation and other fields.

[0015] In the present invention, by mixing a proper amount of PEK-C resin into the PEEK resin, the adhesion, flexibility and static friction coefficient of the entire insulating layer can be effectively improved.

[0016] In the present invention, the tensile strength of PEK-C is 94-100 MPa, the tensile modulus is 2.4-2.8 GPa, the flexural strength is 132-150 MPa, and the flexural modulus is 2.7-3.1 GPa.

[0017] During specific mixing, the mass proportion of PEK-C is 10%-49%, and the mass proportion of PEEK is 51%-90%.

[0018] The phenolphthalein polyaryletherketone described in Formula 5 can be a conventional commercially available product, such as the phenolphthalein polyaryletherketone (Mw is about 52,000) produced by Xuzhou Engineering Plastics Factory of Changchun Institute of Applied Chemistry, Chinese Academy of Sciences.

[0019] In addition, the present invention also obtains PEK-C by laboratory synthesis. Phenolphthalein and dichlorobenzophenone are added to a mixed solution of DMAC and ethylbenzene in an equivalent ratio, and the temperature is gradually increased from 150 to 200° C. under alkaline catalytic conditions for 2 hours. After the reaction, the viscosity of the system is about 1.1 dL / g, and the weight average molecular weight Mw of the product is about 50,000.

[0020] The second object of the present invention is to provide a method for preparing any of the above-mentioned insulated wires, comprising: mixing polyetheretherketone resin and phenolphthalein polyaryletherketone resin in a predetermined weight ratio, and stirring so that the polyetheretherketone resin material and the phenolphthalein polyaryletherketone resin material are evenly distributed to form a mixed resin, adding the mixed resin material into a twin-screw extruder barrel, and heating it to a molten state of 370 to 400° C., then mixing it through a twin-screw extruder, and after cooling, granulating it through a pelletizer to obtain a mixed resin material with a particle size of 2 to 3 mm, i.e., the material of the insulating layer, and then coating the obtained material on the periphery of the conductor.

[0021] Among them, the material of polyetheretherketone resin is a 2-3mm particle material, with a glass transition temperature (Tg): 143°C and a melting point (Tm): 334°C; PEK-C material is: 2-3mm particle material, glass transition temperature (Tg): 230-232℃, thermal decomposition temperature above 450℃.

[0022] The mixed resin material, i.e. the wire insulation material, is added to a single screw extruder, heated to a molten state at 370-400°C, coated on a conductor after extrusion, and cooled to form an insulation layer to obtain an insulated wire.

[0023] During coating, the conductor may be preheated at a temperature of 280-330°C.

[0024] Another object of the present invention is to provide a coil composed of the above-mentioned insulated wire.

[0025] The present invention also aims to provide an electrical or electronic device prepared by the coil.

[0026] Compared with the prior art, the present invention has the following advantages: The wire insulation material provided by the present invention is used to prepare the insulation layer of the wire, which can improve the adhesion between the pure PEEK resin and the copper conductor and improve the flexibility of the insulation material; and PEK-C and PEEK both belong to polyaromatic ketones and have the same ether bond and ketone group, so the two have good compatibility, which helps to improve the overall strength and stability of the blended material; PEK-C has a lower static friction coefficient, so the insulation surface of the wire is smoother, making it easier to insert into the stator during use and avoiding friction with the stator. DETAILED DESCRIPTION

[0027] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the connotation of the present invention, so the present invention is not limited to the specific implementation disclosed below.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] Example 1: (Conductor size is 1.90ⅹ2.90mm) This embodiment provides an insulated wire, including a conductor and an insulating layer arranged on the outer periphery of the conductor. The material of the insulating layer is obtained by mixing and granulating polyetheretherketone and phenolphthalein polyaryletherketone. Specifically, the structure of polyetheretherketone (PEEK) is shown in Formula 4 below:

[0030] Formula 4; The structural formula of phenolphthalein polyaryletherketone (PEK-C) is shown in Formula 5 below:

[0031] Formula 5; Among them, n is 150 and m is 100.

[0032] The mass proportion of PEEK is 90%, the mass proportion of PEK-C is 10%, and the crystallinity of the insulating layer is 26%.

[0033] When applied, the total thickness of the insulating layer is 100 μm.

[0034] Example 2 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 80%, the mass proportion of PEK-C is 20%, and the crystallinity of the insulating layer is 23%.

[0035] Example 3 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 70%, the mass proportion of PEK-C is 30%, and the crystallinity of the insulating layer is 20%.

[0036] Example 4 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 60%, the mass proportion of PEK-C is 40%, and the crystallinity of the insulating layer is 17%.

[0037] Example 5 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 51%, the mass proportion of PEK-C is 49%, and the crystallinity of the insulating layer is 15%.

[0038] Comparative Example 1 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 40%, the mass proportion of PEK-C is 60%, and the crystallinity of the insulating layer is 12%.

[0039] Comparative Example 2 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 20%, the mass proportion of PEK-C is 80%, and the crystallinity of the insulating layer is 6%.

[0040] Comparative Example 3 In this embodiment, the difference from Embodiment 1 is that the mass proportion of PEEK is 100%, the mass proportion of PEK-C is 0, and the crystallinity of the insulating layer is 29%.

[0041] Performance Testing The following tests were performed on the insulated wires prepared in Examples 1-5 and Comparative Examples 1-3: 1. Adhesion test The adhesion test method provided by IEC-60851-3 2019 Test Method 8 is used for testing. The specific steps are as follows: Take 300 mm of the insulated wire obtained in the embodiment and the comparative example as a sample, cut a circle of the sample in the middle position until the conductor, and then place the sample between two clamps. The sample and the clamp are placed on the same axis, clamp both ends, stretch 15% at a rate of 300 mm / min, and measure the length of the sample paint film that loses adhesion.

[0042] 2. Flexibility test The insulated wires of the embodiments and comparative examples were tested for flexibility according to the following methods.

[0043] The flexibility test is carried out using the flexibility test method provided by IEC60851-3 2019 test method 8. The specific steps are as follows: Take two 500mm long straight insulated wires, bend them 180±2° around a polished test core, one for flat winding (core diameter = 2 times wire thickness), the other for vertical winding (core diameter = 2 times wire width). In this test, after flat winding and vertical winding, the product with smooth surface and no cracks is recorded as "qualified"; the surface cracks are recorded as "unqualified".

[0044] The test results are shown in the following table:

[0045] It can be seen from the test results that, compared with pure PEEK resin insulating materials, the insulating wire provided by the present invention can improve its adhesion to the conductor and its flexibility by adding an appropriate amount of PEK-C and blending and granulating the insulating material, thereby effectively improving the adhesion and flexibility of pure PEEK resin.

[0046] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An insulated wire, characterized in that: It includes a conductor and an insulating layer arranged on the periphery of the conductor, wherein the insulating layer is made by mixing and granulating two resins, resin A and resin B, and the mixed material contains the units shown in the following formulas 1 to 3: Formula 1, Formula 2: Formula 3; Among them, the molar proportion of the unit shown in formula 1 is 3-17%, the molar proportion of the unit shown in formula 2 is 37-77%, and the molar proportion of the unit shown in formula 3 is 20-47%.

2. The insulated wire according to claim 1, wherein: The crystallinity of the material is 15-26%.

3. The insulated wire according to claim 1, wherein: The resin A is polyetheretherketone resin.

4. The insulated wire according to claim 3, wherein: The structural formula of the polyetheretherketone resin is shown in Formula 4 below: Formula 4; Among them, m is 50~200.

5. The insulated wire according to claim 1, wherein: The resin B is a phenolphthalein-based polyaryletherketone resin.

6. The insulated wire according to claim 5, characterized in that The structural formula of the phenolphthalein polyaryletherketone resin is shown in Formula 5 below: Formula 5; Among them, n is 50~150.

7. The method for preparing the insulated wire according to any one of claims 1 to 6, characterized in that: include: The polyetheretherketone resin and the phenolphthalein polyaryletherketone resin are mixed in a predetermined weight ratio and stirred so that the polyetheretherketone resin material and the phenolphthalein polyaryletherketone resin material are evenly distributed to form a mixed resin. The mixed resin material is added into a barrel of a twin-screw extruder and heated to a molten state of 370 to 400°C. The mixed resin material is then blended through a twin-screw extruder to form a uniform mixed system. After cooling, the mixed resin material is granulated through a pelletizer to obtain a mixed resin material with a particle size of 2 to 3 mm, i.e., the material of the insulating layer. The obtained material is then coated on the periphery of the conductor.

8. A coil, characterized in that: The insulated wire is composed of any one of claims 1 to 6.

9. An electronic / electrical device, characterized in that: The invention comprises the coil as claimed in claim 8.

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