Mica tape and method of making same

Abstract

The application discloses a mica tape, which comprises a mica paper layer and a reinforcing fiber fabric layer, the mica paper layer is formed on one side surface of the reinforcing fiber fabric layer, and a modified polyimide film is further formed between the mica paper layer and the reinforcing fiber fabric layer; the two side surfaces of the modified polyimide film are coated with a glue permeation inhibitor layer, an adhesive powder layer is sprayed on the outer surface of the glue permeation inhibitor layer, the adhesive powder layer is formed into an adhesive layer through hot pressing, and the mica paper layers, the reinforcing fiber fabric layer and the modified polyimide film on the two sides are adhered and formed into an integrated body; meanwhile, the application further discloses a preparation method of the mica tape, the mica tape has a lower glue content, the glue has a smaller influence on the infiltration performance of the mica paper, and the mica tape has better VPI process performance.

Description

Technical Field

[0001] This invention relates to the fields of high voltage insulation technology and electrical insulation materials, specifically to a mica tape and its preparation method. Background Technology

[0002] In recent years, with the continuous development of my country's economy and the progress of science and technology, people's demand for electricity has gradually increased, and the application of insulating materials in electrical equipment has also attracted attention. Mica tape, as a type of insulating material, has advantages such as high temperature resistance, high pressure resistance, aging resistance, corrosion resistance, and insulation; it also possesses physical properties such as high shear strength and tensile strength, and is widely used in industry as an insulating wrapping material in cables and large electromechanical equipment.

[0003] Because the reduced-resin VPI main insulation increases the mica content, it can significantly reduce insulation thickness and improve various performance aspects of the motor, such as voltage withstand and corona resistance, resulting in a qualitative leap in high-voltage motor technology and thus a broader application prospect. Therefore, in the field of high-voltage motors, the use of reduced-resin mica tape can effectively improve the performance of electrical equipment while ensuring the insulation level, achieving goals such as increasing voltage, increasing capacitance, and reducing size. This allows the corresponding high-voltage motor equipment to operate reliably for a long time under harsh conditions such as high temperature and high load, thereby reducing operation and maintenance costs.

[0004] With the development of the power industry, modern power generation and transmission equipment are gradually developing towards high voltage, large capacity, and integration. The main insulation structure of some large high voltage generator sets with a capacity of one million kilowatts in my country has become larger, with a thickness of up to 5-7 mm. Therefore, higher requirements are placed on the high temperature resistance, strength performance, and insulation performance of electrical insulation paper. The existing low-adhesion mica tape mainly consists of mica paper, reinforcing fiber fabric layer, and adhesive. It uses solvent and resin to prepare mica tape adhesive solution, impregnates the reinforcing material, and then composites it with mica paper. The solvent is then removed by heating. Because mica paper itself has a strong adhesive absorption capacity, the mica paper prepared under this method will have excessive liquid adhesive filling the gaps between the mica particles, resulting in reduced air permeability of the mica tape. This is not conducive to VPI (Vibration Partial Insulation) and makes it difficult for the mica paper to meet the above-mentioned usage requirements. Under large-size insulation structure conditions, partial discharge will occur, making it difficult to meet the electrical insulation performance requirements and affecting the long-term operating life of the power generation equipment. In addition, the adhesive solution will also make the reinforcing fiber fabric layer brittle and gaps will appear after a certain period of use, which will also affect the usage requirements of the main insulation material. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a mica tape and its preparation method, so as to overcome the shortcomings in the above-mentioned background technology.

[0006] The technical problem solved by this invention is achieved by the following technical solution:

[0007] A mica tape includes a mica paper layer and a reinforcing fiber fabric layer. The mica paper layer is formed on one side surface of the reinforcing fiber fabric layer. A modified polyimide film is also formed between the mica paper layer and the reinforcing fiber fabric layer. The modified polyimide film has uniformly opened dot matrix holes. Both sides of the modified polyimide film are coated with an adhesive penetration inhibitor layer. An adhesive powder layer is correspondingly sprayed on the outer surface of the adhesive penetration inhibitor layer. The adhesive powder layer is formed into an adhesive layer by hot pressing, and the mica paper layer, the reinforcing fiber fabric layer and the modified polyimide film on both sides are bonded together to form a whole.

[0008] The modification process of the modified polyimide film is as follows:

[0009] First, the sample was modified by soaking in a weakly acidic solution of citrate and sodium dimethyl isophthalate-5-sulfonate (SIPM). Then, it was removed, dried, and modified by soaking in a graphene oxide solution for the second time.

[0010] The single pore diameter of the lattice holes does not exceed 3 mm, and the area ratio of the lattice holes in the modified polyimide film per unit area is 27-35%.

[0011] As a further limitation, the mica paper layer is preferably synthetic fluoromica paper or phlogopite paper.

[0012] As a further limitation, the reinforcing fiber fabric layer is an alkali-free glass fiber cloth layer.

[0013] As a further limitation, the reinforcing fiber fabric layer is a high-performance fabric layer, which is a polyacrylonitrile fiber fabric layer or a carbon fiber fabric layer, and a TiN layer is formed on the surface of the high-performance fabric layer by magnetron sputtering technology.

[0014] As a further limitation, the adhesive powder used in the adhesive powder layer is prepared from a base resin material, and contains not less than 5 wt% polyvinyl alcohol (PVA), 0.7 to 1.5 wt% graphene oxide (GO), and not more than 0.3 wt% sodium carboxymethyl cellulose (CMC); the base resin material is epoxy resin or silicone resin.

[0015] As a further limitation, the amount of adhesive powder used in the adhesive powder layer is 8-15 g / m³. 2 .

[0016] As a further limitation, the polyimide film is a polyimide film with a thickness not exceeding 0.08 mm that has undergone corona resistance treatment.

[0017] As a further limitation, when performing polyimide film modification treatment:

[0018] In a weakly acidic solution of citrate and sodium dimethyl isophthalate-5-sulfonate, the mass concentration of citrate is 3.5–5 wt%, the mass concentration of sodium dimethyl isophthalate-5-sulfonate is 1.5–3 wt%, the pH value is 6.3–6.7, and the treatment time is 30–45 s.

[0019] The graphene oxide solution is an exfoliated graphene oxide solution prepared by directly adding graphene oxide obtained by the Hummers method to deionized water. The mass concentration of the graphene oxide solution is 3-5 g / L, and the treatment time is 120-180 s.

[0020] As a further limitation, the adhesive penetration inhibitor is a composite reagent, wherein the main inhibitor is glycine and the auxiliary inhibitor is citric acid or citrate; the concentration of the main inhibitor is 1.75 to 3.50 wt% and the concentration of the auxiliary inhibitor is 0.15 to 0.30 wt%.

[0021] A method for preparing mica tape, which specifically includes the following steps:

[0022] S1 selects a polyimide film with a thickness of 0.05-0.08 mm as raw material, punches holes in its surface to obtain a polyimide film intermediate with a dot matrix on the surface, and then spreads the polyimide film intermediate with a dot matrix on the surface into a weakly acidic solution of citrate and sodium dimethyl isophthalate-5-sulfonate for the first soaking modification, then takes it out, dries it, and then uses a graphene oxide solution for the second soaking modification. After taking it out, draining it and air drying it, the modified polyimide film is obtained.

[0023] S2 lays the mica paper layer flat, and then uses electrostatic spraying to coat the surface of the mica paper layer with a layer of adhesive powder; then coats both sides of the modified polyimide film with an adhesive penetration inhibitor layer, and covers one side of the above-mentioned mica paper layer.

[0024] S3 uses high-pressure spraying to sequentially spray adhesive onto the corresponding dot matrix holes of the modified polyimide film on the other side, controlling the amount and position of the adhesive to ensure that the adhesive powder can completely cover the corresponding dot matrix holes.

[0025] S4 Then, a reinforcing fiber fabric layer with a release film is laid flat on the surface of the adhesive powder layer on the other side of the modified polyimide film. After being fed into the equipment for preheating, it is hot-pressed to melt the adhesive powder layer and form it into an adhesive layer. After cooling and curing, it is wound up and slit to obtain the finished mica tape.

[0026] Beneficial effects: The mica tape with the above-mentioned structural features obtained by the method of the present invention has the advantages of high air permeability and good impregnation, as well as good electrical properties. It has low adhesive content, good flexibility, and low cost of use. It can replace traditional low-adhesion mica tape in high-voltage electromechanical equipment. When using the VPI process for high thermal conductivity insulation impregnation, it can significantly shorten the processing time of the VPI process and improve the impregnation ratio and impregnation effect, thereby improving the insulation density. The insulation structure after VPI treatment can remain undelaminated and free of dust during long-term use, which can greatly improve the electrical performance and operational reliability of the motor and reduce the manufacturing cost of the motor. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a preferred embodiment of the present invention.

[0028] The components are: 1. Release film; 2. Reinforcing fiber fabric layer; 3. Modified polyimide film; 4. Adhesive layer; 5. Mica paper layer. Detailed Implementation

[0029] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations and embodiments.

[0030] In the following embodiments, those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0031] In an embodiment, the mica tape includes a mica paper layer 5 and a reinforcing fiber fabric layer 2. A release film 1 is formed on the upper surface of the reinforcing fiber fabric layer 2, and a modified polyimide film 3 is formed between the mica paper layer 5 and the reinforcing fiber fabric layer 2. The modified polyimide film 3 has uniformly opened dot matrix holes, and adhesive penetration inhibitor layers are coated on both sides of the modified polyimide film 3.

[0032] Meanwhile, an adhesive layer 4 is formed between the modified polyimide film 3 and the reinforcing fiber fabric layer 2, and between the modified polyimide film 3 and the mica paper layer 5. The adhesive layer 4 is formed by hot pressing and stabilizing the adhesive powder.

[0033] In embodiments of the present invention, mica tape having the above-described structure can be prepared by the following different embodiments:

[0034] Example 1:

[0035] First, select and process the raw materials:

[0036] Includes a 0.05 mm thick polyimide film treated with corona resistance;

[0037] And synthetic fluoromica paper with a thickness of 0.12 mm;

[0038] And a polyacrylonitrile fiber fabric layer with a thickness of 0.15 mm, the surface of which is coated with a TiN layer by magnetron sputtering technology, and a release film is formed on the surface of the TiN layer;

[0039] Sodium citrate and sodium dimethyl isophthalate-5-sulfonate were dissolved in acetic acid solution, and the pH of the mixture was controlled at 6.4-6.5, the mass concentration of citrate was 3.5 wt%, and the mass concentration of sodium dimethyl isophthalate-5-sulfonate was 3 wt%, to obtain modified solution one. At the same time, graphene oxide prepared by the Hummers method was added to deionized water to prepare exfoliated graphene oxide solution, and the mass concentration of graphene oxide in the graphene oxide solution was controlled at 3.5 g / L, which is modified solution two.

[0040] Adhesive powder was prepared using epoxy resin as the base resin material. The epoxy equivalent of the resin was 970 g / equivalent. The adhesive powder also contained 7 wt% polyvinyl alcohol, 1.2 wt% graphene oxide, and 0.05 wt% sodium carboxymethyl cellulose. The adhesive powder was obtained by mixing the above powders evenly.

[0041] A mixture solution was prepared by adding glycine as the main inhibitor and sodium citrate as the auxiliary inhibitor to water, with the concentration of glycine at 1.75 wt% and the concentration of sodium citrate at 0.22 wt%.

[0042] Before proceeding with the specific preparation process, the polyimide film is first subjected to surface punching treatment to obtain a polyimide film with a lattice of holes on the surface. The punching equipment is controlled so that the single hole diameter of the lattice holes on the polyimide film does not exceed 3mm, and the area ratio of the lattice holes in the modified polyimide film per unit area is 32%, thus obtaining the intermediate polyimide film material.

[0043] The perforated polyimide film intermediate material is spread evenly in modification solution one and treated for 30 seconds. Then it is taken out, the surface liquid is blown off and then air-dried. After air-drying, it is added to modification solution two and treated for 150 seconds. After taking it out, it is drained and air-dried to obtain modified polyimide film 3. Then, a layer of adhesive penetration inhibitor is coated on both sides of the modified polyimide film 3.

[0044] Then, synthetic fluoromica paper, used as the raw material for mica paper, is laid flat as mica paper layer 5. A layer of adhesive powder is then coated onto the surface of mica paper layer 5 using electrostatic spraying, with the amount of adhesive powder controlled at 10-12 g / m². 2 Then, one side of the modified polyimide film 3 coated with the adhesive penetration inhibitor layer is placed on the surface of the mica paper layer 5. On the other side of the modified polyimide film 3, adhesive powder is sequentially sprayed onto the corresponding dot matrix positions of the modified polyimide film 3 using high-pressure spraying, while controlling the amount of adhesive powder to be 10-12 g / m². 2 The adhesive powder completely covers the corresponding lattice holes. Then, a reinforcing fiber fabric layer 2 with release film 1 is laid flat on the adhesive powder layer surface on the other side of the modified polyimide film 3. After being fed into the equipment for preheating, it is hot-pressed and laminated, so that the adhesive powder layer melts and is formed into adhesive layer 4 on both sides of the modified polyimide film 3 under pressure. Then, it is cooled down, so that the adhesive layer 4 is cured, and then wound and cut to obtain the finished mica tape.

[0045] The parameters of the finished mica tape obtained above are as follows:

[0046] Width: 25mm, thickness: 0.355mm, mica paper basis weight: 81.7g / mm² 2 Adhesive content 7.44%, air permeability: 384S / 100cm 3 The tensile strength is 119 N / 10 mm.

[0047] Example 2:

[0048] First, select and process the raw materials:

[0049] Includes a 0.06 mm thick polyimide film treated with corona resistance;

[0050] And synthetic fluoromica paper with a thickness of 0.2 mm;

[0051] A carbon fiber fabric layer with a thickness of 0.18 mm is formed on the surface of which a TiN layer is coated by magnetron sputtering technology, and a release film is formed on the surface of the TiN layer.

[0052] Sodium citrate and sodium dimethyl isophthalate-5-sulfonate were dissolved in acetic acid solution, and the pH of the mixture was controlled at 6.6-6.7, the mass concentration of citrate was 3.5-4 wt%, and the mass concentration of sodium dimethyl isophthalate-5-sulfonate was 2 wt%, to obtain modified solution one. At the same time, graphene oxide prepared by the Hummers method was added to deionized water to prepare an exfoliated graphene oxide solution, and the mass concentration of graphene oxide in the graphene oxide solution was controlled at 3.5 g / L, which is modified solution two.

[0053] An adhesive powder was prepared using epoxy resin as the base resin material. The epoxy equivalent of the resin was 1300 g / equivalent. The adhesive powder also contained 6 wt% polyvinyl alcohol and 1 wt% graphene oxide. The adhesive powder was obtained by mixing the above powders evenly.

[0054] A mixture solution was prepared by adding glycine as the main inhibitor and sodium citrate as the auxiliary inhibitor to water, with the concentration of glycine at 3.30 wt% and the concentration of sodium citrate at 0.28 wt%.

[0055] Before proceeding with the specific preparation process, the polyimide film is first subjected to surface punching treatment to obtain a polyimide film with a lattice of holes on the surface. The punching equipment is controlled so that the single hole diameter of the lattice holes on the polyimide film does not exceed 3mm, and the area ratio of the lattice holes in the modified polyimide film per unit area is 30%, thus obtaining the intermediate polyimide film material.

[0056] The perforated polyimide film intermediate material is spread evenly in modification solution one and treated for 45 seconds. Then it is taken out, the surface liquid is blown off and then air-dried. After air-drying, it is added to modification solution two and treated for 180 seconds. After taking it out, it is drained and air-dried to obtain modified polyimide film 3. Then, a layer of adhesive penetration inhibitor is coated on both sides of the modified polyimide film 3.

[0057] Then, synthetic fluoromica paper, used as the raw material for mica paper, is laid flat as mica paper layer 5. A layer of adhesive powder is then coated onto the surface of mica paper layer 5 using electrostatic spraying, with the amount of adhesive powder controlled at 13-15 g / m². 2 Then, one side of the modified polyimide film 3 coated with the adhesive penetration inhibitor layer is placed on the surface of the mica paper layer 5. On the other side of the modified polyimide film 3, adhesive powder is sequentially sprayed onto the corresponding dot matrix positions of the modified polyimide film 3 using high-pressure spraying, while controlling the amount of adhesive powder to be 13-15 g / m³. 2 The adhesive powder completely covers the corresponding lattice holes. Then, a reinforcing fiber fabric layer 2 with release film 1 is laid flat on the adhesive powder layer surface on the other side of the modified polyimide film 3. After being fed into the equipment for preheating, it is hot-pressed and laminated, so that the adhesive powder layer melts and is formed into adhesive layer 4 on both sides of the modified polyimide film 3 under pressure. Then, it is cooled down, so that the adhesive layer 4 is cured, and then wound and cut to obtain the finished mica tape.

[0058] The parameters of the finished mica tape obtained above are as follows:

[0059] Width: 25mm, thickness: 0.473mm, mica paper basis weight: 88.6g / mm² 2Adhesive content 9.17%, air permeability: 436S / 100cm 3 The tensile strength is 131 N / 10 mm.

[0060] Example 3:

[0061] First, select and process the raw materials:

[0062] Includes a 0.08 mm thick polyimide film treated with corona resistance;

[0063] and phlogopite paper with a thickness of 0.1 mm;

[0064] And a polyacrylonitrile fiber fabric layer with a thickness of 0.15 mm, the surface of which is coated with a TiN layer by magnetron sputtering technology, and a release film is formed on the surface of the TiN layer;

[0065] Sodium citrate and sodium dimethyl isophthalate-5-sulfonate were dissolved in acetic acid solution, and the pH of the mixture was controlled at 6.5-6.6, the mass concentration of citrate was 4.3 wt%, and the mass concentration of sodium dimethyl isophthalate-5-sulfonate was 2.4 wt%, to obtain modified solution one. At the same time, graphene oxide prepared by the Hummers method was added to deionized water to prepare an exfoliated graphene oxide solution, and the mass concentration of graphene oxide in the graphene oxide solution was controlled at 4 g / L, which is modified solution two.

[0066] Adhesive powder was prepared using epoxy resin as the base resin material. The epoxy equivalent of the resin was 1100 g / equivalent. The adhesive powder also contained 6.5 wt% polyvinyl alcohol, 1.2 wt% graphene oxide, and 0.15 wt% sodium carboxymethyl cellulose. The adhesive powder was obtained by mixing the above powders evenly.

[0067] A mixture solution was prepared by adding glycine as the main inhibitor and sodium citrate as the auxiliary inhibitor to water, with the concentration of glycine at 2.85 wt% and the concentration of sodium citrate at 0.25 wt%.

[0068] Before proceeding with the specific preparation process, the polyimide film is first subjected to surface punching treatment to obtain a polyimide film with a lattice of holes on the surface. The punching equipment is controlled so that the single hole diameter of the lattice holes on the polyimide film does not exceed 3mm, and the area ratio of the lattice holes in the modified polyimide film per unit area is 35%, thus obtaining the intermediate polyimide film material.

[0069] The perforated polyimide film intermediate material is spread evenly in modification solution one and treated for 42 seconds. Then it is taken out, the surface liquid is blown off and then air-dried. After air-drying, it is added to modification solution two and treated for 160 seconds. After taking it out, it is drained and air-dried to obtain modified polyimide film 3. Then, a layer of adhesive penetration inhibitor is coated on both sides of the modified polyimide film 3.

[0070] Then, phlogopite paper, used as the raw material for mica paper, is laid flat as mica paper layer 5. A layer of adhesive powder is then coated onto the surface of mica paper layer 5 using electrostatic spraying, with the amount of adhesive powder controlled at 11-12 g / m². 2 Then, one side of the modified polyimide film 3 coated with the adhesive penetration inhibitor layer is placed on the surface of the mica paper layer 5. On the other side of the modified polyimide film 3, adhesive powder is sequentially sprayed onto the corresponding lattice positions of the modified polyimide film 3 using high-pressure spraying, while controlling the amount of adhesive powder to be 11-12 g / m². 2 The adhesive powder completely covers the corresponding lattice holes. Then, a reinforcing fiber fabric layer 2 with release film 1 is laid flat on the adhesive powder layer surface on the other side of the modified polyimide film 3. After being fed into the equipment for preheating, it is hot-pressed and laminated, so that the adhesive powder layer melts and is formed into adhesive layer 4 on both sides of the modified polyimide film 3 under pressure. Then, it is cooled down, so that the adhesive layer 4 is cured, and then wound and cut to obtain the finished mica tape.

[0071] The parameters of the finished mica tape obtained above are as follows:

[0072] Width: 25mm, thickness: 0.339mm, mica paper basis weight: 79.8g / mm² 2 Adhesive content 8.45%, air permeability: 354S / 100cm 3 The tensile strength is 117 N / 10 mm.

[0073] In the previous embodiment, the finished mica tape obtained can be repeatedly wrapped and folded without being easily damaged. The process of producing mica tape is relatively simple and is particularly suitable for manufacturing mica tape products with extremely low glue content for use in high-temperature and high-pressure motor electrical insulation. It can make up for the defects of ordinary mica tape being easily damaged during the wrapping process. Under VPI process conditions, it is theoretically and technologically feasible to replace traditional low-glue mica tape.

[0074] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A mica tape, characterized in that, The device comprises a mica paper layer and a reinforcing fiber fabric layer, wherein the mica paper layer is formed on one side surface of the reinforcing fiber fabric layer; a modified polyimide film is also formed between the mica paper layer and the reinforcing fiber fabric layer, wherein the modified polyimide film has uniformly opened dot matrix holes; both sides of the modified polyimide film are coated with an adhesive penetration inhibitor layer, and an adhesive powder layer is correspondingly sprayed on the outer surface of the adhesive penetration inhibitor layer; the adhesive powder layer is formed into an adhesive layer by hot pressing, thereby bonding the mica paper layer, the reinforcing fiber fabric layer and the modified polyimide film on both sides into a single unit; The modification process of the modified polyimide film is as follows: The polyimide film with open pores was first modified by soaking it in a weakly acidic solution of citrate and sodium dimethyl isophthalate-5-sulfonate. Then it was taken out, dried, and modified by soaking it in a graphene oxide solution for the second time. The single pore diameter of the lattice holes does not exceed 3 mm, and the area ratio of the lattice holes in the modified polyimide film per unit area is 27-35%.

2. The mica tape according to claim 1, characterized in that, The mica paper layer is synthetic fluoromica paper or phlogopite paper.

3. The mica tape according to claim 1, characterized in that, The reinforcing fiber fabric layer is an alkali-free fiberglass cloth layer.

4. The mica tape according to claim 1, characterized in that, The reinforcing fiber fabric layer is a high-performance fabric layer, which is a polyacrylonitrile fiber fabric layer or a carbon fiber fabric layer, and a TiN layer is formed on the surface of the high-performance fabric layer by magnetron sputtering technology.

5. The mica tape according to claim 1, characterized in that, The adhesive powder used in the adhesive powder layer is prepared from a base resin material, and contains not less than 5 wt% polyvinyl alcohol, 0.7-1.5 wt% graphene oxide and not more than 0.3 wt% sodium carboxymethyl cellulose; the base resin material is epoxy resin or silicone resin.

6. The mica tape according to claim 1, characterized in that, The amount of adhesive powder used in the adhesive powder layer is 8-15 g / m2.

7. The mica tape according to claim 1, characterized in that, The polyimide film is a polyimide film with a thickness not exceeding 0.08 mm that has undergone corona resistance treatment.

8. The mica tape according to claim 1, characterized in that, The adhesive penetration inhibitor is a composite reagent, with glycine as the main inhibitor and citric acid or citrate as the auxiliary inhibitor; the concentration of the main inhibitor is 1.75-3.50 wt%, and the concentration of the auxiliary inhibitor is 0.15-0.30 wt%.

9. A method for preparing mica tape, used to prepare the mica tape according to claim 1, characterized in that, Specifically, the following steps are included: S1 selects a polyimide film with a thickness of 0.05-0.08 mm as raw material, punches holes in its surface to obtain a polyimide film intermediate with a dot matrix on the surface, and then spreads the polyimide film intermediate with a dot matrix on the surface into a weakly acidic solution of citrate and sodium dimethyl isophthalate-5-sulfonate for the first soaking modification, then takes it out, dries it, and then uses a graphene oxide solution for the second soaking modification. After taking it out, draining it and air drying it, the modified polyimide film is obtained. S2 lays the mica paper layer flat, and then uses electrostatic spraying to coat the surface of the mica paper layer with a layer of adhesive powder; then coats both sides of the modified polyimide film with an adhesive penetration inhibitor layer, and covers one side of the above-mentioned mica paper layer. S3 uses high-pressure spraying to sequentially spray adhesive onto the corresponding dot matrix holes of the modified polyimide film on the other side, controlling the amount and position of the adhesive to ensure that the adhesive powder can completely cover the corresponding dot matrix holes. S4 Then, a reinforcing fiber fabric layer with a release film is laid flat on the surface of the adhesive powder layer on the other side of the modified polyimide film. After being fed into the equipment for preheating, it is hot-pressed to melt the adhesive powder layer and form it into an adhesive layer. After cooling and curing, it is wound up and slit to obtain the finished mica tape.

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