A high-protection mica composite material for cable wrapping and filling and a preparation method thereof

Abstract

The present application relates to the field of mica composite materials for cable wrapping filling, in particular to a high-protection mica composite material for cable wrapping filling and a preparation method thereof. A high-protection mica composite material for cable wrapping filling, comprising a flexible composite mica matrix, a ceramic modified reinforced silicone rubber, an adhesive and a release paper; the ceramic modified reinforced silicone rubber is respectively compounded on the upper and lower surfaces of the flexible composite mica matrix; the adhesive is compounded on the surface of one of the ceramic modified reinforced silicone rubber facing away from the flexible composite mica matrix; the release paper is compounded with the adhesive; the thickness ratio of the flexible composite mica matrix to the ceramic modified reinforced silicone rubber is controlled at 100:(60‑120); the thickness of the flexible composite mica matrix is ​​controlled at 0.5‑0.8mm. The present application can play an excellent fire retardant role when used as a filling material for cable wrapping, and effectively improves the overall fire resistance and heat resistance and flame retardancy of the cable.

Description

Technical Field

[0001] The present application relates to the field of cable winding and filling mica composite materials, and in particular to a high-protection mica composite material for cable winding and filling and a preparation method thereof. Background Art

[0002] With the rapid development of the economy, the installed kilometers of cables increase year by year. As the "transmission blood vessels" of electric power and electronic information, it is particularly important to provide fire and flame retardant safety protection for cables. The importance of fire and flame retardant safety protection for cables lies in that power cable fire accidents occur frequently at home and abroad, causing a certain degree of economic losses and related negative social impacts. In the densely laid cable channels, how to effectively prevent the spread of cable fires and the expansion of accidents is an urgent problem to be solved.

[0003] Currently, in order to improve the flame retardant and fire safety coefficient of cables, related technologies use mica wrapping tapes to wrap cable wires, and then obtain fire-resistant cables with fire protection performance. The mica wrapping tapes used have advantages such as high electrical insulation, high fire resistance, large dielectric constant, small loss, high dielectric strength, and high chemical stability, which can improve the flame retardant and fire protection performance of the wrapped cables.

[0004] Regarding the mica wrapping tapes in the above related technologies, the applicant found that the following defects exist in this solution: Although the mica wrapping tapes are used to wrap cable wires to improve the flame retardant and fire protection performance of the wrapped cables, due to the flexible requirements of the mica wrapping tapes, the glue content is relatively high (between 15% - 25%). When the mica wrapping tapes are affected by external heat sources, the silicone resin in them thermally decomposes, resulting in the destruction of the overall structure. The obtained residue is brittle and hard, and can no longer play a good anti-external force protection effect, and the overall fire resistance effect needs to be improved. Summary of the Invention

[0005] In order to solve the above technical problems, the present application provides a high-protection mica composite material for cable winding and filling and a preparation method thereof.

[0006] In the first aspect, a high-protection mica composite material for cable winding and filling provided by the present application is achieved through the following technical solutions:

[0007] A high-protection mica composite material for cable winding and filling, comprising a flexible composite mica matrix, a ceramized modified reinforced silicone rubber, an adhesive, and a release paper; the ceramized modified reinforced silicone rubber is respectively compounded on the upper and lower surfaces of the flexible composite mica matrix; the adhesive is compounded on the surface of one of the ceramized modified reinforced silicone rubbers facing away from the flexible composite mica matrix; the release paper is compounded with the adhesive; the thickness ratio of the flexible composite mica matrix to the ceramized modified reinforced silicone rubber is controlled at 100:(60-120); the thickness of the flexible composite mica matrix is controlled at 0.5-0.8 mm; the thickness of the flexible composite mica matrix is controlled at 0.5-0.8 mm; the flexible composite mica matrix includes a flexible mica roll unit and a reinforcing mesh cloth, and the reinforcing mesh cloth is hot-pressed and compounded between the flexible mica roll units.

[0008] By adopting the above technical solutions, the flexible composite mica matrix adopted endows the whole with good fireproof and flame-retardant properties and relatively good flexibility, and can be applied to cable winding and filling materials. During the actual winding process, the flexible composite mica matrix in this application is not prone to cracks, fissures, and fractures. After further formula improvement of the ceramized modified reinforced silicone rubber in this application, it has excellent fire and heat resistance properties, which can not only ensure the overall fireproof and flame-retardant properties, but also improve the overall flexibility and reduce the probability of cracks, fissures, and fractures during the overall use process. To sum up, the cable winding and filling material prepared in this application can play an excellent fireproof and flame-retardant role, effectively improve the overall fire resistance and heat-resistant flame-retardant properties of the cable, and improve the use safety of the wire and cable.

[0009] Secondly, a preparation method of a high-protection mica composite material for cable winding and filling provided by this application is realized through the following technical solutions:

[0010] A preparation method of a high-protection mica composite material for cable winding and filling includes the following steps:

[0011] Step 1, preparation of a semi-finished flexible composite mica matrix;

[0012] At the same time, preparation of the ceramized modified reinforced silicone rubber;

[0013] Step 2, compound the ceramized modified reinforced silicone rubber on the upper and lower surfaces of the semi-finished flexible composite mica matrix, place it in a hot-pressing device for hot-pressing and compounding treatment, and cool to obtain a semi-finished product; the semi-finished product includes a finished flexible composite mica matrix and the ceramized modified reinforced silicone rubber hot-pressed and compounded on the finished flexible composite mica matrix;

[0014] Step 3, scrape and coat an organosilicon glue on the upper surface of the semi-finished product to form an adhesive, compound a release paper on the adhesive, and wind and cut to obtain a finished high-protection mica composite material.

[0015] The preparation method of this application is relatively simple, with low operation difficulty, and is convenient for realizing industrial production and manufacturing. Moreover, the prepared material for cable wrapping and filling can play an excellent fireproof and flame-retardant role, effectively improving the overall fire resistance and heat-resistant and flame-retardant properties of the cable.

[0016] Preferably, the flexible mica roll unit is mainly prepared from surface-modified phlogopite powder aggregate, silicone resin liquid, and toughening agent; the glue content of the flexible mica roll unit is controlled at 16-18%; the content of the toughening agent in the flexible mica roll unit is controlled at 1-3%; the toughening agent is at least one of zinc oxide whiskers and silicon carbide whiskers in combination with at least one of alumina short fibers and aramid short fibers; the surface-modified phlogopite powder aggregate is obtained by dry stirring with γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane.

[0017] By adopting the above technical solution, controlling the glue content of the flexible mica roll unit can improve the flexibility of the flexible composite mica matrix and take into account better fireproof and flame-retardant properties. However, too much glue content will not only lead to a decrease in fireproof and flame-retardant performance but also cause a decrease in mechanical properties. Too low a glue content will result in a too hard composite mica matrix, and problems such as cracks, fissures, and fractures are likely to occur during the wrapping process. The glue content of the flexible mica roll unit in this application is preferably controlled at 17±0.2%. In addition, in this application, a toughening agent is used to repair the defects of the matrix resin and improve the overall structural regularity, thereby improving the flexibility and mechanical strength of the prepared flexible composite mica matrix and overcoming the problems of cracks, fissures, and fractures that are likely to occur during the wrapping process. The surface-modified phlogopite powder aggregate enables it to be more evenly dispersed in the matrix, and the modified matrix carried on the phlogopite powder aggregate forms chemical bonds with the molecular chains generated by the polymerization of the specific resin, which can further ensure the mechanical strength, flame-retardant, fire-resistant, and heat-resistant properties of the flexible composite mica material prepared in this application.

[0018] Preferably, in Step 1, the preparation of the semi-finished flexible composite mica matrix is as follows:

[0019] S1.1, Use γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane to perform dry stirring on the prepared phlogopite powder aggregate to obtain surface-modified phlogopite powder aggregate;

[0020] S1.2, Prepare a surface-modified aqueous solution with a concentration of 4-8 g / L of γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane, place the toughening agent in the surface-modified aqueous solution for ultrasonic treatment for 30-60 minutes, and drain and dry to obtain the finished toughening agent;

[0021] S1.3, mix the silicone resin liquid and the organic solvent that acts as a diluent, then add the surface modified phlogopite powder aggregate and the finished toughening agent and mix them evenly to obtain the finished mica slurry;

[0022] S1.4, mica slurry is placed in a molding mold, heated to remove the organic solvent in the silicone resin liquid and the organic solvent added for dilution, and then preheated and pressed, and release paper is laminated on the upper and lower surfaces to obtain a semi-finished flexible composite mica matrix. The release paper on the laminate needs to be peeled off when in use.

[0023] The preparation method of the semi-finished flexible composite mica matrix provided in this application is relatively simple, with low operating difficulty, which is convenient for industrial mass production and manufacturing, and reduces the production cost of the semi-finished flexible composite mica matrix. In addition, it is also convenient for the production of high-protection mica composite materials used for cable wrapping and filling in this application.

[0024] Preferably, the silicone resin in the silicone resin liquid is an epoxy-modified silicone resin; the epoxy-modified silicone resin is mainly prepared from silicone resin and epoxy-modified resin, and the molar ratio of the silicone resin to the epoxy-modified resin is controlled at 100:(18-20); the epoxy-modified resin is composed of bisphenol S epoxy resin, 4.4-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane epoxy resin; the molar ratio of the bisphenol S epoxy resin, 4.4-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane epoxy resin is 78:(10-12):15:5; the silicone resin is methyl vinyl siloxane with a number average molecular weight of 10 3 -10 4 double-terminal vinyl reaction silicone; the methyl vinyl siloxane is matched with a number average molecular weight of 10 3 -10 4 The molar ratio of double-terminal vinyl-reactive silicone is 1:(20-30).

[0025] By adopting the above technical solution, it is ensured that the flexible composite mica matrix has good flame retardant and fireproof properties and has a certain flexibility. At the same time, the mechanical strength of the prepared flexible composite mica matrix can be improved, thereby improving the mechanical strength of the overall wrapping filling material and making up for the defect of weak mechanical properties of the silicone rubber matrix material.

[0026] ​​Preferably, the preparation of the epoxy-modified silicone resin: Mix accurately metered bisphenol S-type epoxy resin, 4,4'-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane-type epoxy resin evenly, then add xylene to dilute the viscosity. After mixing evenly, add DMP-30 catalyst, flush with nitrogen to exhaust air, and then heat up to 110-115°C. Dropwise add silicone resin at a dropping rate controlled at 4-6 g / min. After the silicone resin is added dropwise, maintain the reaction at 110-115°C for 120-150 min. After the reaction is completed, cool to room temperature to obtain the finished epoxy-modified silicone resin.

[0027] The preparation method of the epoxy-modified silicone resin provided in this application is relatively simple, the equipment used is relatively conventional and the operation difficulty is low, which is convenient for reducing the production difficulty and improving the batch production efficiency.

[0028] Preferably, the ceramized modified reinforced silicone rubber (2) is mainly made of the following raw materials in parts by weight: 100 parts of methyl vinyl silicone oil, 0.5-0.8 parts of crosslinking agent, 100-120 parts of porcelain-forming filler, 35-45 parts of reinforcing agent, 15-20 parts of flux, and 2-4 parts of vulcanizing agent;

[0029] The crosslinking agent is at least one of methyl tributanone oxime silane, phenyl tributanone oxime silane, vinyl tributanone oxime silane, γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, N,N'-1,3-phenylene bismaleimide, N,N'-(4,4'-methylenediyl)bismaleimide;

[0030] The porcelain-forming filler is one or a combination of hybrid or unhybrid fluorophlogopite powder aggregate, wollastonite aggregate, diatomite aggregate, kaolin aggregate, montmorillonite aggregate that have been surface-modified;

[0031] The reinforcing agent is one or a combination of fumed silica, boron trioxide, yttrium trioxide, alumina fiber, quartz fiber, carbon fiber, fumed silica hybrid alumina fiber, and hydroxy silicone oil;

[0032] The flux is at least one of glass powder, zinc oxide, boron oxide, and zinc borate;

[0033] The vulcanizing agent is one or a combination of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, and dicumyl peroxide.

[0034] By adopting the above technical scheme, the ceramized modified reinforced silicone rubber prepared has good flame retardancy and fire and heat resistance, and can play a good protective role for the wrapped cable.

[0035] Preferably, the porcelain-forming filler is an aggregate, which is composed of fillers with different particle sizes in the following mass percentages: 10-15% of the filler screened through a 1000-mesh sieve, 35-40% of the filler with a particle size of 800-1000 meshes, 25-30% of the filler with a particle size of 500-800 meshes, and the balance of the filler with a particle size of 300-500 meshes; the filler is at least one of fluorophlogopite powder, wollastonite powder, diatomite powder, kaolin powder, and montmorillonite powder.

[0036] By adopting the above technical solution, the porcelain-forming filler is an aggregate. When the silicone rubber matrix is completely decomposed by heat, the decomposition product is amorphous SiO 2 powder, which is convenient for accelerating the formation of a "bridging" structure between the flux in the molten state and the decomposition residue of the silicone rubber and the porcelain-forming filler, so that each part is combined into a porous but hard whole. On the premise of ensuring the overall refractory and heat-resistant effect, the amount of the porcelain-forming filler can be appropriately reduced, thereby reducing the overall production cost and improving the flexibility and elasticity of the prepared ceramized modified reinforced silicone rubber.

[0037] Preferably, the cross-linking agent is composed of vinyltri(t-butanone oxime)silane, γ-methacryloxypropyltrimethoxysilane, and N,N'-(4,4'-methylenediyl)bismaleimide; the porcelain-forming filler is a hybrid or unhybridized fluorophlogopite powder aggregate, wollastonite aggregate, or diatomite aggregate that has undergone surface modification treatment; the reinforcing agent is composed of fumed silica, boron trioxide, fumed silica hybrid alumina fiber, and hydroxy silicone oil; the flux is composed of glass powder and zinc borate.

[0038] The formula of the ceramized modified reinforced silicone rubber can further improve the performance of the prepared ceramized modified reinforced silicone rubber and ensure the overall production stability and the quality stability of the same batch.

[0039] Preferably, the preparation method of the ceramized modified reinforced silicone rubber is as follows:

[0040] S1.01, preparation of the porcelain-forming filler; and accurately weighing the remaining raw materials at the same time;

[0041] S1.02, uniformly mixing the accurately weighed porcelain-forming filler, reinforcing agent, and flux, adding them to the accurately weighed methyl vinyl silicone oil and cross-linking agent, stirring evenly, and placing the obtained material in a mixer for mixing and blending;

[0042] S1.03, adding a vulcanizing agent and placing it in an open mill for mixing and blending, and vulcanizing and molding: placing it in a flat vulcanizer, vulcanizing at 175-178 °C and 10 ± 0.5 MPa for 10-12 min, and then placing it in an oven at 198-204 °C for 120-135 min to obtain the finished ceramized modified reinforced silicone rubber.

[0043] The preparation method of the ceramized modified reinforced silicone rubber provided in this application is relatively simple. The equipment used in production and manufacturing is relatively conventional, and the operation difficulty of the equipment is relatively low, which is convenient for reducing the production difficulty, improving the batch production efficiency, and achieving the purpose of industrial production and manufacturing of ceramized modified reinforced silicone rubber sheets.

[0044] In summary, this application has the following advantages:

[0045] 1. The cable wrapping and filling material of this application can play an excellent fireproof and flame-retardant role, effectively improving the overall fire resistance and heat-resistant flame-retardant performance of the cable.

[0046] 2. The preparation method of this application is relatively simple and has a low operation difficulty, which is convenient for realizing industrial production and manufacturing. Brief Description of the Drawings

[0047] Figure 1 It is a schematic diagram of the overall structure of Embodiment 1 in this application.

[0048] In the figure, 1. Flexible composite mica matrix; 11. Flexible mica roll unit; 12. Reinforcing mesh cloth; 2. Ceramized modified reinforced silicone rubber; 3. Adhesive; 4. Release paper. Detailed Description of the Embodiments

[0049] The following further elaborates on this application in combination with comparative examples and embodiments.

[0050] Embodiment

[0051] Embodiment 1

[0052] Refer to Figure 1 , a high-protection mica composite material for cable wrapping and filling disclosed in this application, includes a flexible composite mica matrix 1 and a ceramized modified reinforced silicone rubber 2. The ceramized modified reinforced silicone rubber 2 is thermally pressed and compounded on the upper and lower surfaces of the flexible composite mica matrix 1 respectively. An adhesive 3 and a release paper 4 are sequentially compounded upward on the surface of the ceramized modified reinforced silicone rubber 2 facing away from the flexible composite mica matrix 1. Among them, the flexible composite mica matrix 1 and the ceramized modified reinforced silicone rubber 2 are self-made. The adhesive 3 is a commercially available high-temperature resistant silicone adhesive, and the release paper 4 is a commercially available conventional release paper.

[0053] The thickness ratio of the flexible composite mica matrix 1 to the ceramized modified reinforced silicone rubber 2 is controlled at 100:(60 - 120). In this embodiment, the thickness ratio of the two is controlled at 100:60.

[0054] The thickness of the flexible composite mica matrix 1 is controlled at 0.5 - 0.8 mm. In this embodiment, the thickness of the flexible composite mica matrix 1 is controlled at 0.65 ± 0.05 mm.

[0055] Reference Figure 1 Figure 1 , the flexible composite mica substrate 1 includes a flexible mica roll unit 11 and a reinforcing mesh cloth 12, and the reinforcing mesh cloth 12 is thermally pressed and compounded between the flexible mica roll units 11. The commercially available reinforcing mesh cloth 12 used in this application is a fiberglass mesh cloth.

[0056] The flexible mica roll unit 11 is mainly prepared from surface-modified phlogopite powder aggregate, silicone resin liquid, and toughening agent. Among them, the glue content of the flexible mica roll unit 11 is controlled at 16-18%; in this embodiment, the glue content of the flexible mica roll unit 11 is controlled at 17% ± 0.2%. The content of the toughening agent in the flexible mica roll unit 11 is controlled at 1-3%, and in this embodiment, the toughening agent is controlled at 2.4%. The silicone resin liquid used is Shin-Etsu KR 242A of Japan (solid content 50%, organic solvents - xylene, isopropanol).

[0057] The toughening agent is at least one of zinc oxide whiskers and silicon carbide whiskers combined with at least one of alumina short fibers and aramid short fibers. In this application, the toughening agent is composed of zinc oxide whiskers combined with alumina short fibers (3M Nextel alumina fiber, length controlled at 43-46 mm), and the mass ratio of zinc oxide whiskers (tetrapod zinc oxide whiskers ZnO, length: 10-50 um; diameter: 0.5-5 um) combined with alumina short fibers is controlled at 2:8.

[0058] The surface-modified phlogopite powder aggregate is obtained by dry stirring with γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane. Specifically, in this embodiment, the surface-modified phlogopite powder aggregate is obtained by dry stirring with γ-methacryloxypropyltrimethoxysilane K570.

[0059] Before modification, the phlogopite powder aggregate is composed of 15% of phlogopite powder screened by a 1000-mesh sieve, 40% of phlogopite powder with a mesh size of 800-1000, 25% of phlogopite powder with a mesh size of 500-800, and 20% of phlogopite powder with a mesh size of 300-500.

[0060] The ceramized modified reinforced silicone rubber 2 is made from the following raw materials in parts by weight: 100 parts of methyl vinyl silicone oil, 0.5-0.8 parts of crosslinking agent, 100-120 parts of porcelain-forming filler, 35-45 parts of reinforcing agent, 15-20 parts of flux, and 2-4 parts of vulcanizing agent.

[0061] The preferred formulation is as follows: The ceramized modified reinforced silicone rubber 2 is made from the following raw materials in parts by weight: 100 parts of methyl vinyl silicone oil, 0.5 - 0.6 parts of crosslinking agent, 100 - 102 parts of porcelain-forming filler, 36 - 38 parts of reinforcing agent, 16 - 17 parts of flux, and 2 - 2.2 parts of vulcanizing agent.

[0062] The crosslinking agent is at least one of methyltributanoneoxime silane, phenyltributanoneoxime silane, vinyltributanoneoxime silane, γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, N,N'-1,3-phenylene bismaleimide, N,N'-(4,4'-methylenediyl)bismaleimide.

[0063] The porcelain-forming filler is one or a combination of hybrid or non-hybrid fluorophlogopite powder aggregate, wollastonite aggregate, diatomite aggregate, kaolin aggregate, montmorillonite aggregate that have been surface-modified.

[0064] The porcelain-forming filler is an aggregate, which is composed of fillers with different particle sizes in the following mass percentages: 10 - 15% of the filler screened through a 1000-mesh sieve, 35 - 40% of the filler with a particle size of 800 - 1000 meshes, 25 - 30% of the filler with a particle size of 500 - 800 meshes, and the balance is the filler with a particle size of 300 - 500 meshes. The filler is at least one of fluorophlogopite powder, wollastonite powder, diatomite powder, kaolin powder, montmorillonite powder.

[0065] The reinforcing agent is one or a combination of fumed silica, boron trioxide, yttrium trioxide, alumina fiber, quartz fiber, carbon fiber, fumed silica hybrid alumina fiber, hydroxy silicone oil.

[0066] The flux is at least one of glass powder, zinc oxide, boron oxide, zinc borate.

[0067] The vulcanizing agent is one or a combination of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, dicumyl peroxide.

[0068] The formulation of the ceramized modified reinforced silicone rubber in this example is as follows: 100 parts of methyl vinyl silicone oil, 0.15 parts of crosslinking agent - γ-methacryloxypropyltrimethoxysilane, 0.2 parts of crosslinking agent - vinyltributanoneoxime silane, 0.2 parts of crosslinking agent - N,N'-(4,4'-methylenediyl)bismaleimide, 100 parts of porcelain-forming filler, 20 parts of fumed silica, 3 parts of boron trioxide, 10 parts of fumed silica hybrid alumina fiber, 5 parts of hydroxy silicone oil 107, 5 parts of glass powder, 12 parts of zinc borate, 2 parts of vulcanizing agent - 2,4-dichlorobenzoyl peroxide.

[0069] The porcelain-forming filler is composed of surface-modified fluorophlogopite powder aggregate, wollastonite aggregate, and diatomite aggregate. The mass ratio of the surface-modified fluorophlogopite powder aggregate, wollastonite aggregate, and diatomite aggregate is 45:30:25.

[0070] The particle sizes of the fluorophlogopite powder aggregate, wollastonite aggregate, and diatomite aggregate are the same, specifically as follows: 15% of the filler sieved through a 1000-mesh sieve, 40% of the filler with a particle size of 800 - 1000 meshes, 25% of the filler with a particle size of 500 - 800 meshes, and the balance is the filler with a particle size of 300 - 500 meshes.

[0071] The surface modification method of the porcelain-forming filler is as follows: Prepare an aqueous solution of K570 siloxane with a concentration of 6 g / L, place the porcelain-forming filler in the aqueous solution of K570 siloxane, perform ultrasonic dispersion treatment for 30 min, drain and dry to obtain the finished porcelain-forming filler.

[0072] Preparation method of fumed silica hybrid alumina fiber: Weigh 50 g of fumed silica and mix it evenly with 1000 g of commercially available aqueous polyurethane (aqueous PU polyurethane resin MR-711 polyurethane emulsion) with a solid content of 48 - 50% to obtain a fumed silica treatment solution; Spray the fumed silica treatment solution on the surface of alumina fiber (3M Nextel alumina fiber), and the mass ratio of the sprayed fumed silica treatment solution to the alumina fiber is 10:100. After spraying, place it in an oven at 60 °C for 40 min, take it out and let it cool naturally to room temperature to obtain fumed silica hybrid alumina fiber.

[0073] A preparation method of a high-protection mica composite material for cable wrapping and filling includes the following steps:

[0074] Step 1, preparation of semi-finished flexible composite mica matrix 1;

[0075] S1.1, specific preparation method of surface-modified phlogopite powder aggregate, as follows:

[0076] First, weigh the phlogopite powder sieved through a 1000-mesh sieve, phlogopite powder with a particle size of 800 - 1000 meshes, phlogopite powder with a particle size of 500 - 800 meshes, and phlogopite powder with a particle size of 300 - 500 meshes respectively for standby;

[0077] Then, place the phlogopite powder sieved through a 1000-mesh sieve, phlogopite powder with a particle size of 800 - 1000 meshes, phlogopite powder with a particle size of 500 - 800 meshes, and phlogopite powder with a particle size of 300 - 500 meshes into γ-methacryloyloxypropyltrimethoxysilane K570 respectively for dry grinding and mixing. The mass ratio of phlogopite powder to γ-methacryloyloxypropyltrimethoxysilane K570 is 100:8. Stir at 360 rpm for 30 min, drain, and finally dry to obtain the finished surface-modified phlogopite powder aggregate;

[0078] S1.2. Prepare an aqueous solution for surface modification. The aqueous solution for surface modification contains 6 g of vinyltriethoxysilane per liter. Place the toughening agent in the aqueous solution for surface modification and perform ultrasonic treatment for 40 min. Drain and dry to obtain the finished toughening agent.

[0079] S1.3. Mix 300 g of organosilicon resin solution KR 242A evenly with 160 g of xylene, an organic solvent for dilution. Then add 806 g of surface-modified phlogopite powder aggregate and 24 g of the finished toughening agent and mix evenly to obtain the finished mica slurry. S1.4. Place the mica slurry in a molding die, heat to remove the organic solvent in the organosilicon resin solution and the added organic solvent for dilution. Preheat and press: hot press at 85.0 °C and 0.35 MPa for 60 s to obtain a prefabricated mica piece. Then, attach release paper to the upper and lower surfaces of the prefabricated mica piece to obtain a semi-finished flexible composite mica matrix 1. When used in subsequent processes, only need to uncover the release paper attached to the prefabricated mica piece.

[0080] At the same time, prepare a ceramized modified reinforced silicone rubber, and the specific preparation steps are as follows;

[0081] S1.01. Preparation of the ceramic-forming filler: Prepare a fluorophlogopite powder aggregate, a wollastonite aggregate, and a diatomite aggregate, and place them in a 6 g / L K570 siloxane aqueous solution. Perform ultrasonic dispersion treatment for 30 min, drain, and dry to obtain the finished ceramic-forming filler.

[0082] At the same time, accurately weigh the raw materials: methyl vinyl silicone oil, crosslinking agent, reinforcing agent, fluxing agent, and vulcanizing agent, and accurately measure according to the formula for standby.

[0083] S1.02. Mix the accurately measured ceramic-forming filler, reinforcing agent, and fluxing agent evenly and add them to the accurately measured methyl vinyl silicone oil and crosslinking agent. Stir evenly. Place the obtained material in a mixer and perform co-mixing in the mixer at 100 ± 0.5 °C for 30 min.

[0084] S1.03. Add the vulcanizing agent and perform open mixing and co-mixing on an open mill, and pass through thinly to produce sheets.

[0085] S1.04. Vulcanization and molding: Place it in a flat vulcanizer and vulcanize at 175 °C and 10 MPa for 10 min. Then place it in an oven and place it at 200 °C for 120 min to obtain the finished ceramized modified reinforced silicone rubber.

[0086] Step 2. Compound the ceramized modified reinforced silicone rubber on the upper and lower surfaces of the semi-finished flexible composite mica matrix 1, and place it in a hot pressing device for hot pressing and compounding treatment:

[0087] The first step, the hot pressing temperature is 110 °C, the pressure is 0.5 MPa, hot press for 20 s, then vent for 3 s and then hot press for 5 s. The total hot pressing time is 25 s.

[0088] Step 2: The hot pressing temperature is 145°C, the pressure is 0.8 MPa. After hot pressing for 25 s, vent for 3 s, then hot press for 25 s and vent for 3 s, then hot press for 25 s and vent for 3 s, then hot press for 25 s and vent for 3 s. The total hot pressing time is 100 s;

[0089] Step 3: The hot pressing temperature is 205°C, the pressure is 1.0 MPa, and the hot pressing duration is 180 s;

[0090] Step 4: The hot pressing temperature is 130°C, the pressure is 0.6 MPa, and the duration is 80 s

[0091] Step 5: The hot pressing temperature is 95°C, the pressure is 0.40 MPa, and the duration is 120 s. After completing the five-step hot pressing to form a semi-finished mica plate, place it at 80°C and keep it warm for 120 min, then cool to obtain the semi-finished product;

[0092] The obtained semi-finished product includes a finished flexible composite mica matrix 1 and a ceramized modified reinforced silicone rubber 2 hot-pressed and compounded on the finished flexible composite mica matrix 1;

[0093] Step 3: Scrape and coat the upper surface of the semi-finished product prepared in Step 2 with commercially available silicone rubber to form an adhesive 3, compound a release paper 3 on the adhesive 3, and wind and cut to obtain a finished high-protection mica composite material.

[0094] Example 2

[0095] The difference between Example 2 and Example 1 is that the diatomaceous earth powder sieved through a 1000-mesh sieve in the diatomaceous earth powder aggregate in the porcelain-forming filler is replaced with active zinc hybrid diatomaceous earth with a particle size D50 = 500 nm.

[0096] Example 3

[0097] The difference between Example 3 and Example 1 is that the silicone resin solution used is a self-made silicone resin solution.

[0098] The silicone resin is prepared from 45% KR-242A silicone resin, 5% fluorosilicone, 0.1% diethylenetriamine, and the balance is methanol.

[0099] The fluorosilicone is prepared from perfluorohexylethyl mercaptan (CAS No.: 34451-26-8, molecular formula: C8H5F13S, molecular weight: 380.17), FM-0721 silicone with a number average molecular weight of 5000, and azobisisobutyronitrile.

[0100] The preparation of the silicone resin includes the following steps:

[0101] Step 1, Preparation method of fluorosiloxane: 19.01 g of perfluorohexylethyl mercaptan and 250 g of FM-0721 siloxane are placed in a three-necked flask, heated in a water bath to 45 °C, 0.1 g of azodiisobutyronitrile is added, stirred at 240 rpm, and subjected to a thiolation reaction for 2 h to obtain fluorosiloxane;

[0102] Step 2, After mixing and stirring the fluorosiloxane prepared in Step 1 with 2560.1 g of KR-242A silicone resin at 160 rpm for 3 min, the temperature is raised to 72 °C, and a pre-reaction is carried out for 150 s;

[0103] Step 3, Cool down to between 0 - 4 °C with ice water, then add 2555.0 g of methanol, stir at 200 rpm for 10 min, add 5.12 g of diethylenetriamine, and stir at 80 rpm for 60 s to obtain an organosilicon resin.

[0104] Example 4

[0105] The difference between Example 4 and Example 1 is that: the organosilicon resin liquid uses a self-made organosilicon resin liquid.

[0106] The organosilicon resin in the organosilicon resin liquid is an epoxy-modified organosilicon resin.

[0107] The epoxy-modified organosilicon resin is mainly prepared from an organosilicon resin and an epoxy-modified resin, and the molar ratio of the organosilicon resin to the epoxy-modified resin is controlled at 100:18.

[0108] The epoxy-modified resin is composed of bisphenol S-type epoxy resin combined with 4,4'-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol A-type epoxy resin. Among them, the molar ratio of bisphenol S-type epoxy resin, 4,4'-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol A-type epoxy resin is 78:12:15:5.

[0109] The organosilicon resin is methyl vinyl siloxane 110-2 combined with a bis-terminal vinyl reactive silicone FM-7711 (JNC) with a number average molecular weight of 10 3 The molar ratio of methyl vinyl siloxane combined with a bis-terminal vinyl reactive silicone FM-7711 (JNC) with a number average molecular weight of 10 3 is 1:20.

[0110] Preparation of epoxy-modified silicone resin: Accurately measure bisphenol S-type epoxy resin, 4,4'-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane-type epoxy resin, mix them evenly, then add xylene to dilute the viscosity. After mixing evenly, add DMP-30 catalyst, flush with nitrogen to exhaust air, and then heat up to 110 °C. Dropwise add silicone resin at a dropping rate controlled at 5.0 g / min. After the silicone resin is added dropwise, maintain the reaction at 110 - 112 °C for 120 min. After the reaction is completed, cool to room temperature to obtain the finished epoxy-modified silicone resin.

[0111] Example 5

[0112] The difference between Example 5 and Example 4 is that the molar ratio of silicone resin to epoxy-modified resin is controlled at 100:20.

[0113] Example 6

[0114] The difference between Example 6 and Example 4 is that the molar ratio of methyl vinyl siloxane to the bifunctional vinyl reactive silicone FM-077 (JNC) with a number average molecular weight of 10 3 is 1:25.

[0115] Example 7

[0116] The difference between Example 7 and Example 4 is that the molar ratio of methyl vinyl siloxane to the bifunctional vinyl reactive silicone FM-077 (JNC) with a number average molecular weight of 10 3 is 1:30.

[0117] Example 8

[0118] The difference between Example 8 and Example 4 is that the silicone resin is a combination of methyl vinyl siloxane 110-2 and the bifunctional vinyl reactive silicone FM-7711 (JNC) with a number average molecular weight of 1.0×10 3 , the bifunctional vinyl reactive silicone FM-7721 (JNC) with a number average molecular weight of 5.0×10 3 , and the bifunctional vinyl reactive silicone FM-7725 (JNC) with a number average molecular weight of 1.0×10 4 . The molar ratio of methyl vinyl siloxane 110-2 to the bifunctional vinyl reactive silicone FM-7711 (JNC) with a number average molecular weight of 1.0×10 3 , the bifunctional vinyl reactive silicone FM-7721 (JNC) with a number average molecular weight of 5.0×10 3 , and the bifunctional vinyl reactive silicone FM-7725 (JNC) with a number average molecular weight of 1.0×10 4 is 100:12:8:4.

[0119] Comparative Example

[0120] The difference between Comparative Example 1 and Example 1 lies in that the porcelain-forming filler is only the fluorophlogopite powder aggregate after surface modification treatment, and wollastonite aggregate and diatomite aggregate are not added.

[0121] The difference between Comparative Example 2 and Example 1 lies in that the porcelain-forming filler is composed of surface-modified fluorophlogopite powder (particle size D50 = 40 - 50 μm), wollastonite powder (particle size D50 = 40 - 50 μm), and diatomite powder (particle size D50 = 40 - 50 μm). The mass ratio of the surface-modified fluorophlogopite powder, wollastonite powder, and diatomite powder is 45:30:25.

[0122] The difference between Comparative Example 3 and Example 1 lies in that the formulation of the ceramized and modified reinforced silicone rubber is as follows: 100 parts of methyl vinyl silicone oil, 0.55 parts of crosslinking agent - γ-methacryloxypropyltrimethoxysilane, 100 parts of porcelain-forming filler, 20 parts of fumed silica, 3 parts of boron trioxide, 10 parts of fumed silica hybrid alumina fiber, 5 parts of hydroxy silicone oil 107, 5 parts of glass powder, 12 parts of zinc borate, 2 parts of vulcanizing agent - 2,4-dichlorobenzoyl peroxide.

[0123] The difference between Comparative Example 4 and Example 1 lies in that the formulation of the ceramized and modified reinforced silicone rubber is as follows: 100 parts of methyl vinyl silicone oil, 0.15 parts of crosslinking agent - γ-methacryloxypropyltrimethoxysilane, 0.2 parts of crosslinking agent - vinyltri(t-butyldiketonoxime)silane, 0.2 parts of crosslinking agent - N,N'-(4,4'-methylenediyl)bismaleimide, 100 parts of porcelain-forming filler, 30 parts of fumed silica, 3 parts of boron trioxide, 5 parts of hydroxy silicone oil 107, 5 parts of glass powder, 12 parts of zinc borate, 2 parts of vulcanizing agent - 2,4-dichlorobenzoyl peroxide.

[0124] The difference between Comparative Example 5 and Example 1 lies in that the formulation of the ceramized and modified reinforced silicone rubber is as follows: 100 parts of methyl vinyl silicone oil, 0.15 parts of crosslinking agent - γ-methacryloxypropyltrimethoxysilane, 0.2 parts of crosslinking agent - vinyltri(t-butyldiketonoxime)silane, 0.2 parts of crosslinking agent - N,N'-(4,4'-methylenediyl)bismaleimide, 100 parts of un-surface-treated porcelain-forming filler, 20 parts of fumed silica, 3 parts of boron trioxide, 10 parts of fumed silica hybrid alumina fiber, 5 parts of hydroxy silicone oil 107, 17 parts of zinc borate, 2 parts of vulcanizing agent - 2,4-dichlorobenzoyl peroxide.

[0125] The difference between Comparative Example 6 and Example 4 lies in that the molar ratio of the silicone resin to the epoxy-modified resin is controlled at 100:15.

[0126] The difference between Comparative Example 7 and Example 4 lies in that the molar ratio of the silicone resin to the epoxy modified resin is controlled at 100:25.

[0127] The difference between Comparative Example 8 and Example 4 lies in that the silicone resin is only methyl vinyl siloxane.

[0128] The difference between Comparative Example 9 and Example 4 lies in that the molar ratio of methyl vinyl siloxane to the bifunctional vinyl reactive silicone FM-077 (JNC) with a number average molecular weight of 10 3 is 1:10.

[0129] The difference between Comparative Example 10 and Example 4 lies in that the molar ratio of methyl vinyl siloxane to the bifunctional vinyl reactive silicone FM-077 (JNC) with a number average molecular weight of 10 3 is 1:40.

[0130] Performance detection test

[0131] Detection method / Test method

[0132] 1. The tensile strength, elongation at break and tear strength are respectively tested on a universal testing machine according to GB / T 528-2009 and GB / T 529-2008. The test speed is 500 mm / min, and the average value is taken from 5 groups of tests. The tensile specimen is a standard type 3 dumbbell-shaped specimen, and the test specimen is a crescent-shaped specimen, and the average value is taken from 5 groups of tests.

[0133] 2. Fire resistance test: Test according to T / ZZB 1722-2020. Instruments: A gas burner that can generate different high-temperature flame temperatures by adjusting the flow rate of propane or butane, and a K-type thermocouple thermometer with a 1.5 m insulated stainless steel sheath. Specimen size and quantity: (200 mm ± 10 mm) * (280 mm ± 10 mm), 3 pieces. Measurement steps: Place the specimen vertically at a distance of 65 mm ± 5 m from the flame, ignite the flame, adjust the flow rate of propane or butane, so that the temperature of the middle part of the specimen facing the flame is 1100 ± 100 °C. Burn at this temperature and keep the burning time for 5 min, then remove the flame and check whether the specimen is burned through.

[0134] 3. Flame retardancy test: Test according to the provisions of UL 94.

[0135] 4. Electrical strength test: Test according to Article 22, "Electrical strength" in the test method for mica products of GB / T 5019.2-2009. The thickness of the specimen is 0.39 mm - 0.41 mm, and a Φ25 mm / Φ75 mm cylindrical electrode system is used. The rapid voltage rise method (voltage rise speed is 1.0 kV / s) is carried out in 25# transformer oil at 23 °C ± 2 °C.

[0136] 5. Tensile Strength Test: Test according to GB / T 1040.2-2022.

[0137] The ceramized modified reinforced silicone rubber is cut into splines of corresponding sizes and placed in a porcelain boat. Then, it is put into a muffle furnace. The temperature is raised to 1000 °C in 100 min, held for 30 min, and then cooled to room temperature and taken out to obtain a ceramic body. The mechanical properties and ceramic body yield of the obtained ceramic body are measured.

[0138] Determination of the Mechanical Properties of the Ceramic Body: Rubber splines with dimensions of 50 mm * 3 mm * 4 mm are placed in a muffle furnace for firing to obtain a ceramic body with a crisp ceramic sound. The test standard is GB / T 6569-2006 Precision Ceramics Bending Strength Test Standard, and the test speed is 0.5 mm / min.

[0139] Determination of the Ceramic Body Yield: Calculate based on the mass of the composite material before ablation and the mass of the ceramic body after ablation. Calculation formula: Y = (m 0 / m) * 100%, where Y is the ceramic yield; m is the mass of the rubber composite material before ablation; m 0 is the mass of the ceramic body after high-temperature ablation at 1000 °C.

[0140] Data Analysis

[0141] Table 1 is the test parameter table of the ceramized modified reinforced silicone rubber in Examples 1-2 and Comparative Examples 1-5

[0142]

[0143]

[0144] Table 2 is the test parameter table of the ceramic bodies formed by the ceramized modified reinforced silicone rubber in Examples 1-2 and Comparative Examples 1-5

[0145] Tensile strength MPa Elongation at break % Tear strength KN*m-1 Ceramic body yield % Example 1 4.86 158.91 12.36 60.69 Example 2 5.02 162.1 12.58 61.21 Comparative Example 1 3.98 148.3 9.21 59.12 Comparative Example 2 3.83 145.2 9.06 58.36 Comparative Example 3 4.53 155.4 11.32 59.01 Comparative Example 4 4.62 156.3 11.39 58.87 Comparative Example 5 4.69 155.8 11.56 59.45

[0146] Combining Examples 1-2 and Comparative Examples 1-5 and referring to Table 1, it can be seen that by comparing Example 1 with Comparative Example 1, the ceramized modified reinforced silicone rubber prepared with the porcelain-forming filler composed of fluorophlogopite powder aggregate, wollastonite aggregate, and diatomite aggregate has better mechanical strength and flame retardancy.

[0147] Combining Examples 1-8 and Comparative Examples 1-10 and referring to Tables 1-2, it can be seen that by comparing Example 1 with Comparative Example 2, when the porcelain-forming filler is the aggregate provided in this application, the ceramized modified reinforced silicone rubber prepared has better mechanical strength and flame retardancy.

[0148] It can be seen from combining Examples 1-8 and Comparative Examples 1-10 and in conjunction with Tables 1-2 that when comparing Example 1 with Comparative Example 3, the crosslinking agent consists of vinyltributanoneoxime silane, γ-methacryloxypropyltrimethoxysilane, and N,N'-(4,4-methylenediyl)bismaleimide. The ceramized modified reinforced silicone rubber prepared has good mechanical strength and flame retardant properties.

[0149] It can be seen from combining Examples 1-8 and Comparative Examples 1-10 and in conjunction with Tables 1-2 that when comparing Example 1 with Comparative Example 4, the reinforcing agent consists of fumed silica, boron trioxide, fumed silica hybrid alumina fiber, and hydroxy silicone oil. The ceramized modified reinforced silicone rubber prepared has good mechanical strength and flame retardant properties. The fumed silica hybrid alumina fiber prepared in this application can improve the fire resistance and flame retardant properties and mechanical strength.

[0150] It can be seen from combining Examples 1-8 and Comparative Examples 1-10 and in conjunction with Tables 1-2 that when comparing Example 1 with Comparative Example 5, for the porcelain-forming filler with surface modification, the ceramized modified reinforced silicone rubber prepared has good mechanical strength and flame retardant properties.

[0151] It can be seen from combining Examples 1-8 and Comparative Examples 1-10 and in conjunction with Tables 1-2 that when comparing Example 1 with Example 2, the porcelain-forming filler composed of fluorophlogopite powder aggregate, wollastonite aggregate, and diatomite aggregate is admixed with active zinc hybrid diatomite, which has a positive effect on the mechanical strength of the ceramized modified reinforced silicone rubber.

[0152] It can be seen from combining Examples 1-8 and Comparative Examples 1-10 and in conjunction with Tables 1-2 that the ceramic body formed by the ceramized modified reinforced silicone rubber in this application also has good flame retardant and fire prevention properties for the wrapped cable, that is, the high-protection mica composite material formed with flexible mica has excellent dual flame retardant and fire prevention properties, effectively improving the overall fire resistance and heat-resistant flame retardant properties of the cable.

[0153] Table 3 is the test parameter table of the flexible composite mica matrix in Examples 1, 3-8, and Comparative Examples 6-10

[0154] Electrical strength kv / mm Tensile strength MPa Refractory performance Flame retardant performance Example 1 27.8 143.4. Not burned through V0 Example 3 28.2 151.2 Not burned through V0 Example 4 28.6 162.4 Not burned through V0 Example 5 28.2 164.2 Not burned through V0 Example 6 28.5 165.5 Not burned through V0 Example 7 28.4 166.3 Not burned through V0 Example 8 28.7 169.4 Not burned through V0 Comparative Example 6 28.9 153.2 Not burned through V0 Comparative Example 7 27.0 166.1 Not burned through V0 Comparative Example 8 28.5 156.8 Not burned through V0 Comparative Example 9 28.3 159.4 Not burned through V0 Comparative Example 10 28.6 167.2 Not burned through V0

[0155] It can be seen from combining Examples 1, 3-8 and Comparative Examples 6-10 and in conjunction with Table 3 that when comparing Example 1 with Examples 3-4, the flexible composite mica matrix prepared by using epoxy-modified organic resin has relatively good mechanical strength and is also convenient for the composite bonding of the flexible composite mica matrix and the ceramized modified reinforced silicone rubber.

[0156] Combined with Examples 1, 3 - 8, Comparative Examples 6 - 10 and Table 3, it can be seen that by comparing Example 1, Example 4 with Comparative Examples 6 - 7, it is more appropriate to control the molar ratio of silicone resin to the epoxy - modified resin in the epoxy - modified silicone resin at 100:(18 - 20). This can ensure that the flexible composite mica matrix has good flame - retardant and fire - prevention properties and certain flexibility. At the same time, it can improve the mechanical strength of the prepared flexible composite mica matrix, and further improve the mechanical strength of the overall wrapping and filling material, making up for the defect of the relatively weak mechanical properties of the silicone rubber matrix material.

[0157] Combined with Examples 1, 3 - 8, Comparative Examples 6 - 10 and Table 3, it can be seen that by comparing Example 1, Examples 5 - 7 with Comparative Examples 8 - 10, the silicone resin is a combination of methyl vinyl siloxane and a difunctional vinyl - reactive silicone with a number - average molecular weight of 10 3 -10 4 and the molar ratio of methyl vinyl siloxane to the difunctional vinyl - reactive silicone with a number - average molecular weight of 10 3 -10 4 is 1:(20 - 30). The prepared flexible composite mica matrix has relatively good flexibility and relatively moderate mechanical strength. During the actual wrapping process of the prepared high - protection mica composite material for cable wrapping and filling, cracks, fissures, and fractures are not likely to occur, effectively improving the quality of the overall product and effectively enhancing the fire - resistant and flame - retardant performance and use safety performance of the wire and cable.

[0158] Combined with Examples 1, 3 - 8, Comparative Examples 6 - 10 and Table 3, it can be seen that by comparing Example 1 with Examples 5 - 8, the silicone resin is composed of methyl vinyl siloxane 110 - 2 and difunctional vinyl - reactive silicones FM - 7711 (JNC) with a number - average molecular weight of 1.0×10 3 , FM - 7721 (JNC) with a number - average molecular weight of 5.0×10 3 , and FM - 7725 (JNC) with a number - average molecular weight of 1.0×10 4 , and the molar ratio of methyl vinyl siloxane 110 - 2 to difunctional vinyl - reactive silicone FM - 7711 (JNC) with a number - average molecular weight of 1.0×10 3 , FM - 7721 (JNC) with a number - average molecular weight of 5.0×10 3 , and FM - 7725 (JNC) with a number - average molecular weight of 1.0×10 4The molar ratio of the double-end vinyl reactive silicone FM-7725 (JNC) is 100:12:8:4. The prepared flexible mica composite coil / tape has better flexibility than that of Example 1 and Examples 5-7, and similar mechanical strength and flame retardant and fireproof properties. It has better operability for the wrapping operation, improves the winding efficiency, that is, after increasing the winding speed of the equipment, the product in Example 8 is not likely to have problems such as cracks, fissures, and fractures due to too fast winding speed, improving the overall yield rate of the wrapped cable, and being well received by downstream wire and cable customers, with relatively good market prospects.

[0159] In summary, the cable wrapping filler material prepared in this application can play an excellent role in fire retardancy, effectively improving the overall fire resistance and heat-resistant flame retardant properties of the cable, and enhancing the use safety of the wire and cable. The preparation method of this application is relatively simple, with low operation difficulty, and is convenient for industrial production and manufacturing.

[0160] This specific embodiment is only an interpretation of this application, and it is not a limitation of this application. Those skilled in the art can make modifications to this embodiment without creative contributions according to needs after reading this specification, but as long as it is within the scope of the claims of this application, it is protected by the patent law.

Claims

1. A method for preparing a high-protection mica composite material for cable wrapping and filling, characterized in that: The following steps are involved: Step 1, preparation of a semi-finished flexible composite mica substrate (1); At the same time, the ceramic modified and reinforced silicone rubber is prepared; Step 2: Compounding the ceramic modified reinforced organic silicone rubber on the upper and lower surfaces of the semi-finished flexible composite mica matrix (1), placing it in a hot pressing device for hot pressing compounding, and cooling to obtain a semi-finished product; the semi-finished product comprises the finished flexible composite mica matrix (1) and the ceramic modified reinforced organic silicone rubber (2) compounded on the finished flexible composite mica matrix (1) by hot pressing; Step three, applying organic silica gel on the upper surface of the semi-finished product to form an adhesive (3), compounding a release paper (4) on the adhesive (3), and rolling and cutting to obtain a finished high-protection mica composite material; the flexible composite mica matrix (1) comprises a flexible mica roll unit (11) and a reinforced mesh cloth (12), and the reinforced mesh cloth (12) is hot-pressed and compounded between the flexible mica roll units (11); The flexible mica roll unit (11) is mainly prepared from surface-modified phlogopite powder aggregate, silicone resin liquid, and toughening agent; the glue content of the flexible mica roll unit (11) is controlled at 16-18%; the content of the toughening agent in the flexible mica roll unit (11) is controlled at 1-3%; the toughening agent is at least one of zinc oxide whiskers and silicon carbide whiskers combined with at least one of aluminum oxide staple fibers and aramid staple fibers; the surface-modified phlogopite powder aggregate is obtained by dry stirring γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane; The ceramic modified reinforced silicone rubber (2) is mainly made of the following raw materials in parts by weight: 100 parts of methyl vinyl silicone oil, 0.5-0.8 parts of a cross-linking agent, 100-120 parts of a ceramic filler, 35-45 parts of a reinforcing agent, 15-20 parts of a flux, and 2-4 parts of a vulcanizing agent; the cross-linking agent is vinyl trisbutyl ketoxime silane combined with γ-methacryloxypropyl trimethoxy silane and N,N ， -(4.4-methylenediyl)bismaleimide; the ceramic filler is a hybrid or unhybridized fluorphlogopite powder aggregate, wollastonite aggregate, or diatomaceous earth aggregate that has been surface-modified; the reinforcing agent is composed of fumed silica, boron trioxide, fumed silica hybrid alumina fiber, and hydroxy silicone oil; the flux is composed of glass powder and zinc borate; the vulcanizing agent is one or more of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, and diisopropylbenzene peroxide.

2. The method for preparing a high-protection mica composite material for cable wrapping and filling according to claim 1, characterized in that: The step 1, preparation of the semi-finished flexible composite mica substrate (1), is specifically as follows: S1.1, dry-mixing the prepared phlogopite powder aggregate with γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane to obtain surface-modified phlogopite powder aggregate; S1.2, γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane are prepared into a surface modification aqueous solution with a concentration of 4-8 g / L, the toughening agent is placed in the surface modification aqueous solution for ultrasonic treatment for 30-60 min, and the toughening agent is drained and dried to obtain a finished toughening agent; S1.3, mixing the silicone resin liquid and the organic solvent for dilution, and then adding the surface modified phlogopite powder aggregate and the finished toughening agent and mixing them evenly to obtain the finished mica slurry; S1.4, mica slurry is placed in a molding mold, heated to remove the organic solvent in the silicone resin liquid and the organic solvent added for dilution, and then laminated with release paper on the upper and lower surfaces after preheating and pressing to obtain a semi-finished flexible composite mica substrate (1). The release paper on the laminate needs to be peeled off when in use.

3. The method for preparing a high-protection mica composite material for cable wrapping and filling according to claim 1, characterized in that: The organic silicone resin in the organic silicone resin liquid is an epoxy-modified organic silicone resin; the epoxy-modified organic silicone resin is mainly prepared from organic silicone resin and epoxy-modified resin, and the molar ratio of the organic silicone resin to the epoxy-modified resin is controlled at 100:(18-20); the epoxy-modified resin is composed of bisphenol S epoxy resin, 4.4-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane epoxy resin; the molar ratio of the bisphenol S epoxy resin, 4.4-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane epoxy resin is 78:(10-12):15:5; the organic silicone resin is methyl vinyl siloxane with a number average molecular weight of 10 3 -10 4 The double-terminal vinyl-reactive silicone; the methyl vinyl siloxane is matched with a number average molecular weight of 10 3 -10 4 The molar ratio of the double-terminal vinyl-reactive silicone is 1:(20-30).

4. The method for preparing a high-protection mica composite material for cable wrapping and filling according to claim 3, characterized in that: Preparation of the epoxy-modified silicone resin: accurately measured bisphenol S epoxy resin, 4.4-diaminodiphenylmethane tetraglycidylamine, polybutadiene epoxy resin, and tetrabromobisphenol propane epoxy resin are mixed evenly, xylene is added to dilute the viscosity, and after mixing evenly, a DMP-30 catalyst is added, nitrogen is injected to exhaust the air, and the temperature is raised to 110-115° C., and the silicone resin is added dropwise, and the dropping speed is controlled at 4-6 g / min. After the silicone resin is added dropwise, the temperature is maintained at 110-115° C. for 120-150 min. After the reaction is completed, the reaction is cooled to room temperature to obtain a finished epoxy-modified silicone resin.

5. The method for preparing a high-protection mica composite material for cable wrapping and filling according to claim 1, characterized in that: The porcelain-forming filler is an aggregate, which is composed of the following mass percentages of fillers of different particle sizes: 10-15% of fillers sieved through 1000 mesh, 35-40% of fillers of 800-1000 mesh, 25-30% of fillers of 500-800 mesh, and the remainder of fillers of 300-500 mesh; the filler is at least one of fluorphlogopite powder, wollastonite powder, diatomaceous earth powder, kaolin powder, and montmorillonite powder.

6. The method for preparing a high-protection mica composite material for cable wrapping and filling according to claim 1, characterized in that: The preparation method of the ceramic modified reinforced silicone rubber is as follows: S1.01, preparation of ceramic filler; at the same time, prepare other raw materials accurately; S1.02, uniformly mix the accurately measured porcelain-forming filler, reinforcing agent and flux, add them to the accurately measured methyl vinyl silicone oil and cross-linking agent, stir evenly, and place the obtained materials in an internal mixer for internal mixing and blending; S1.03, add vulcanizing agent and mix in an open mill, vulcanize and mold: place in a flat vulcanizer, vulcanize at 175-178℃, 10±0.5MPa for 10-12 min, then place in an oven at 198-204℃ for 120-135min to obtain the finished ceramic modified reinforced silicone rubber.

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