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CN-118496759-B - Insulating varnish, enameled wire and preparation method of insulating varnish

CN118496759BCN 118496759 BCN118496759 BCN 118496759BCN-118496759-B

Abstract

The invention relates to the technical field of enameled wires, in particular to enameled wire insulating varnish and an enameled wire suitable for high-frequency electricity. The insulating paint comprises, by mass, 25-40% of polyimide, 15-25% of polyethylene terephthalate, 5-15% of a fluorine-containing polymer, 5.0-10% of a phenolic resin, 3.0-8.0% of a melamine formaldehyde resin, 3.0-8.0% of a silicone resin, 5.0-15% of nano alumina, 5.0-15% of nano silica, 3.0-8.0% of ceramic particles, 1.0-5.0% of a hindered amine light stabilizer and 2.0-8.0% of dioctyl phthalate. The invention has excellent high-frequency electrical performance, heat resistance and mechanical strength, and is suitable for high-frequency and high-efficiency application in modern electronic equipment, such as 5G communication equipment, high-speed motors, power electronic devices and the like.

Inventors

  • FANG XIAOYAN

Assignees

  • 浙江优耐特新材料有限公司

Dates

Publication Date
20260505
Application Date
20240520

Claims (6)

  1. 1. The wire enamel suitable for high-frequency electricity is characterized in that the dry components of the wire enamel comprise the following components in percentage by mass: Polyimide 25-40% 15-25% Of polyethylene terephthalate 5-15% Of fluorine-containing polymer Phenolic resin 5.0-10% 3.0 To 8.0 percent of melamine formaldehyde resin 3.0 To 8.0 percent of silicon resin Nanometer alumina 5.0-15% 5.0 To 15 percent of nano silicon dioxide 3.0 To 8.0 percent of ceramic particles 1.0 To 5.0 percent of hindered amine light stabilizer 2.0 To 8.0 percent of dioctyl phthalate; The fluorine-containing polymer is selected from one or more of polytetrafluoroethylene, polyvinylidene fluoride, perfluoroalkoxy polymer, ethylene-tetrafluoroethylene copolymer and fluoroethylene propylene copolymer; The silicone resin is one or more of methyl silicone resin, phenyl silicone resin and methyl phenyl silicone resin; The average grain diameter of the nano silicon dioxide is 50-100 nanometers, the specific surface area is 100-150 m2/g, the average grain diameter of the nano aluminum oxide is 10-50 nanometers, and the specific surface area is 200-300 m2/g; The ceramic particles are boron nitride with the particle diameter of 20-100 nanometers and the specific surface area of 100-200 m2/g.
  2. 2. The wire enamel as claimed in claim 1, characterized in that the dry composition of the wire enamel consists of the following components in mass percent: Polyimide 30-35% 18-22% Of polyethylene terephthalate 8.0 To 12 percent of fluorine-containing polymer Phenolic resin 5.0-8.0% Melamine formaldehyde resin 4.0-6.0% 4.0 To 6.0 percent of silicon resin 6.0 To 10 percent of nano alumina 6.0 To 10 percent of nano silicon dioxide 4.0 To 6.0 percent of ceramic particles 1.5 To 3.0 percent of hindered amine light stabilizer 3.0 To 5.0 percent of dioctyl phthalate.
  3. 3. The method for preparing wire enamel according to any of claims 1 to 2, characterized in that it comprises the following steps: 1) Dissolution and mixing of matrix resins Weighing polyimide, polyethylene terephthalate and fluorine-containing polymer according to the formula proportion, adding a proper amount of N-methyl pyrrolidone serving as a solvent into a stirrer, adding the resin, and stirring at the speed of 600-800 rpm for 2-3 hours to ensure that the resin is completely dissolved and uniformly mixed; 2) Addition of curing agent Gradually adding the curing agent into the matrix resin solution, and continuously stirring at 600-800 rpm for 1-1.5 hours to ensure uniform mixing; 3) Dispersion of fillers and additives The preparation method comprises the steps of weighing nano alumina, nano silicon dioxide and ceramic particles according to a formula proportion, gradually adding fillers into a mixture of matrix resin and a curing agent by using high-shear dispersing equipment, carrying out high-shear dispersion for 20-30 minutes after each filler is added to ensure uniform dispersion, and finally adding a hindered amine light stabilizer and dioctyl phthalate and continuously stirring for 30-40 minutes.
  4. 4. The method according to claim 3, wherein the high-shear dispersing device comprises an ultrasonic disperser or a high-shear mixer, the ultrasonic power of the ultrasonic disperser is 200-300W, and the high-shear stirring speed of the high-shear mixer is 3000-5000 rpm.
  5. 5. An enameled wire suitable for high-frequency electricity, which is characterized in that the enameled wire insulating varnish is uniformly coated on a copper wire by a coating device, and is prepared by high-temperature drying and curing.
  6. 6. The method for manufacturing an enamel wire for high frequency electricity according to claim 5, wherein the coated copper wire is dried and solidified at a high temperature in the following stages: pre-baking at 80-100deg.C for 10-12 min; medium temperature drying at 150-180 deg.c for 15-18 min; High-temperature curing at 250-300 deg.c for 30-40 min.

Description

Insulating varnish, enameled wire and preparation method of insulating varnish Technical Field The invention relates to the technical field of enameled wires, in particular to enameled wire insulating varnish and an enameled wire suitable for high-frequency electricity. Background Enameled wire (ENAMELLED WIRE) is an important wire widely applied to motors, electric appliances, transformers and electronic equipment, and has the main function of realizing conduction and insulation of current through combination of conductive wire cores and insulating layers. Enamelled wires are usually made of copper or aluminum as conductors, the outer layers being coated with one or more layers of insulating varnish. With the continuous development of electronic devices, particularly, the demands for high frequency, high efficiency and miniaturization are increasing, and the performance requirements of enameled wires are also continuously increasing. Conventional enamelled wires are prone to problems of increased dielectric loss and reduced insulation performance in high-frequency applications, resulting in reduced power transmission efficiency. Meanwhile, as the power of equipment is increased, the temperature of the working environment is continuously increased, and the heat resistance of the traditional enameled wire is difficult to meet the long-term stable operation requirement in a high-temperature environment. In addition, in high frequency equipment and miniaturized applications, the enameled wire needs to have high mechanical strength to resist various mechanical stresses and abrasion, and the conventional material often cannot simultaneously achieve both insulation performance and mechanical strength. In order to meet the requirements of modern high frequency electrical equipment, enamelled wires must possess the following characteristics: 1. The enameled wire needs to keep low dielectric constant and low dielectric loss under a high-frequency working environment so as to ensure high efficiency and stability of electric energy transmission; 2. the enameled wire must have the ability to withstand high temperature environment, keep insulating property and mechanical strength stable for a long time, and is suitable for high temperature application occasions; 3. High mechanical strength in high frequency and miniaturized devices, the enamel wire needs to have good mechanical strength and wear resistance to ensure reliability and durability during operation. Disclosure of Invention In order to solve the technical problems, the invention aims to provide the enamelled wire insulating varnish suitable for high-frequency electricity, which has excellent high-frequency electrical performance, heat resistance and mechanical strength, and is suitable for high-frequency and high-efficiency applications in modern electronic equipment, such as 5G communication equipment, high-speed motors, power electronic devices and the like. In order to achieve the above purpose, the present invention adopts the following technical scheme: The wire enamel suitable for high-frequency electricity comprises the following dry components in percentage by mass: Polyimide 25-40% 15-25% Of polyethylene terephthalate 5-15% Of fluorine-containing polymer Phenolic resin 5.0-10% 3.0 To 8.0 percent of melamine formaldehyde resin 3.0 To 8.0 percent of silicon resin Nanometer alumina 5.0-15% 5.0 To 15 percent of nano silicon dioxide 3.0 To 8.0 percent of ceramic particles 1.0 To 5.0 percent of hindered amine light stabilizer 2.0 To 8.0 percent of dioctyl phthalate. The components in the formula of the invention have the following functions: Polyimide (PI) provides excellent heat resistance, mechanical strength and electrical insulation properties. The polyimide material has good stability at high temperature and is suitable for high-temperature environment. Polyethylene terephthalate (PET) is used for enhancing the mechanical strength and thermal stability of the material, improving the molding processability of the material and having good heat resistance and insulating property; polytetrafluoroethylene (PTFE) provides extremely low dielectric constants and dielectric losses, enhancing the electrical insulation properties of the material, and is particularly useful in high frequency applications. PTFE also has excellent chemical and high temperature resistance; phenolic resin is used as a curing agent to strengthen the mechanical strength and heat resistance of the material and provide excellent thermal stability and insulating property; melamine formaldehyde resin, which further improves the mechanical strength and heat resistance of the material and enhances the wear resistance and surface hardness of the material; methyl phenyl silicone resin, which enhances the heat resistance and electrical insulation performance of the material and improves the weather resistance and chemical stability of the material; nano alumina (Al 2O3) provides high mechanical