Preparation method of high-thermal-conductivity filler modified organic silicon pouring sealant

Abstract

The invention discloses a preparation method of a high-thermal-conductivity filler modified organic silicon pouring sealant, and relates to the technical field of organic silicon pouring sealants. When the high-thermal-conductivity filler modified organic silicon pouring sealant is prepared, flame-retardant modified cyclotetrasiloxane reacts with trifluoropropyl cyclotetrasiloxane, octamethyl cyclotetrasiloxane, tetramethyl tetravinyl cyclotetrasiloxane and deionized water to prepare hydroxyl-terminated polysiloxane, and the hydroxyl-terminated polysiloxane is added into the organic silicon pouring sealant to prepare the high-thermal-conductivity filler modified organic silicon pouring sealant. Then carrying out a reaction with 3-phenyl-7-coumarin isocyanate to prepare modified polysiloxane; the aminated boron nitride is subjected to a reaction with 4-pentenal, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl] propionic acid and methyl isocyano acetate, and modified boron nitride is prepared; and mixing the modified polysiloxane, the modified boron nitride, hydrogen-containing silicone oil and a platinum catalyst, and carrying out thermocuring to obtain the high-thermal-conductivity organic silicon pouring sealant. The high-thermal-conductivity filler modified organic silicon pouring sealant prepared by the invention has good flame retardance, thermal conductivity, aging resistance, super-hydrophobicity and mechanical properties.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of silicone pouring sealant, in particular to a preparation method of high-thermal-conductivity filler modified silicone pouring sealant. BACKGROUND

[0002] With the upgrading of electronic products, the internal electronic components gradually develop towards miniaturization, integrated circuit, high integration and multi-level, the assembly conditions between components become more and more harsh, which leads to a sharp rise in heat generated by power electronic devices and equipment during operation, shortens the service life and seriously affects the performance. Therefore, materials with high thermal conductivity and high thermal stability are needed to meet the high heat dissipation performance requirements of complex electronic integrated modules.

[0003] Silicone materials have excellent heat resistance, electrical insulation, air permeability and chemical stability, and are the preferred material for electronic and electrical assembly pouring. However, the thermal conductivity of silicone materials is very low, usually only about 0.2 W / (m*K); and with the continuous development of electronic industry, aerospace and other fields, the performance of traditional silicone materials has been difficult to meet the requirements of such special environments. How to improve the thermal conductivity and aging resistance of silicone materials has become a hot and difficult point in the field of silicone pouring sealant research. Therefore, the application prepares a high-thermal-conductivity filler modified silicone pouring sealant, which has good thermal conductivity, aging resistance and flame retardance. SUMMARY

[0004] The application aims to provide a preparation method of high-thermal-conductivity filler modified silicone pouring sealant to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the application provides the following technical scheme:

[0006] A preparation method of high-thermal-conductivity filler modified silicone pouring sealant, comprising the following preparation steps:

[0007] (1) Under a nitrogen atmosphere, tetramethyltetavinylcyclotetrasiloxane, 4-(diphenyl phosphine) butanethiol and azobisisobutyronitrile are uniformly mixed, stirred and reacted at 65-75 DEG C for 4-6 hours, cooled to room temperature, added with cyclohexane, washed, distilled under reduced pressure and dried to obtain flame-retardant modified cyclotetrasiloxane;

[0008] (2) Under the atmosphere of nitrogen, the flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, tetramethyl tetravinylcyclotetrasiloxane are mixed uniformly, stirred and mixed at 80-90℃ for 20-40min, heated to 105-110℃, added with tetramethyl ammonium hydroxide and deionized water, stirred and reacted for 6-8h, heated to 150-160℃, stirred for 2-3h, distilled under reduced pressure to prepare a hydroxyl-terminated polysiloxane; under the atmosphere of nitrogen, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are mixed uniformly at a molar ratio of isocyanate group to hydroxyl group of 1: (1-1.02), added with dibutyltin dilaurate and N,N-dimethylformamide, stirred and reacted at 80-90℃ for 6-8h, distilled under reduced pressure to prepare a modified polysiloxane;

[0009] (3) The hydroxylated boron nitride and 98wt% ethanol aqueous solution are mixed uniformly, added with 3-aminopropyl triethoxysilane and ultrasonically dispersed, stirred and reacted at 80℃ for 6-8h, centrifuged, washed and dried to prepare the aminated boron nitride; the aminated boron nitride, 4-pentenal, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanacetate and N,N-dimethylformamide are mixed uniformly, stirred and reacted at room temperature for 10-12h, centrifuged, washed and dried to prepare the modified boron nitride;

[0010] (4) The modified polysiloxane, the modified boron nitride, hydrogen-containing silicone oil and platinum catalyst are mixed uniformly, injected into a mold, vacuum degassed at room temperature, cured at 80-90℃ for 10-12h to prepare a high-thermal-conductivity filler modified organic silicone potting sealant.

[0011] As an optimization, the preparation step of the flame-retardant modified cyclotetrasiloxane in step (1) is as follows: under the atmosphere of nitrogen, tetramethyl tetravinylcyclotetrasiloxane, 4-(diphenyl phosphinyl) butanethiol and azobisisobutyronitrile are mixed uniformly at a mass ratio of 1: (3.5-4): (0.002-0.004), stirred and reacted at 65-75℃ for 4-6h, cooled to room temperature, added with cyclohexane at 0.8-1.2 times of the mass of the tetramethyl tetravinylcyclotetrasiloxane, washed with 0.35mol / L sodium hydroxide aqueous solution for 3-5 times, washed with distilled water until neutral, distilled under reduced pressure, vacuum dried at 50-60℃ for 10-12h to prepare the flame-retardant modified cyclotetrasiloxane.

[0012] As optimization, the preparation step of the modified polysiloxane in step (2) is: under nitrogen atmosphere, mixing the flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane uniformly in a mass ratio of 1: (0.3-0.4): (0.4-0.5): (0.5-0.6), stirring and mixing at 80-90℃ for 20-40 min, increasing the temperature to 105-110℃, adding tetramethylammonium hydroxide in an amount of 0.001-0.002 times the mass of the flame-retardant modified cyclotetrasiloxane, deionized water in an amount of 0.006-0.008 times the mass of the flame-retardant modified cyclotetrasiloxane, stirring and reacting for 6-8 h, increasing the temperature to 150-160℃, stirring for 2-3 h, and distilling under reduced pressure to obtain a hydroxyl-terminated polysiloxane; under nitrogen atmosphere, mixing 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane uniformly in a molar ratio of isocyanate group to hydroxyl group of 1: (1-1.02), adding dibutyltin dilaurate in an amount of 0.002-0.004 times the mass of the 3-phenyl-7-coumarin isocyanate, N,N-dimethylformamide in an amount of 15-20 times the mass of the 3-phenyl-7-coumarin isocyanate, stirring and reacting at 80-90℃ for 6-8 h, and removing the N,N-dimethylformamide by distillation under reduced pressure to obtain the modified polysiloxane.

[0013] As optimization, the hydroxylated boron nitride in step (3) is hydroxylated boron nitride nanosheet with a sheet diameter of 0.1-0.4 μm, which is purchased from Nanjing Xianfeng Nanotechnology Co., Ltd.

[0014] As optimization, the preparation step of the modified boron nitride in step (3) is: mixing the hydroxylated boron nitride and 98 wt% ethanol aqueous solution uniformly in a mass ratio of 1: (10-12), adding 3-aminopropyltriethoxysilane in an amount of 0.06-0.08 times the mass of the hydroxylated boron nitride, ultrasonic dispersion for 20-30 min, stirring and reacting at 80℃ for 6-8 h, centrifugal separation, washing the obtained precipitate with anhydrous ethanol for 3-5 times, and vacuum drying at 50-60℃ for 4-6 h to obtain aminated boron nitride; mixing the aminated boron nitride, 4-pentenal, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanacetate, and N,N-dimethylformamide uniformly in a mass ratio of 1: (0.02-0.03): (0.1-0.12): (0.025-0.035): (10-12), stirring and reacting at room temperature for 10-12 h, centrifugal separation, washing the obtained precipitate with anhydrous ethanol for 3-5 times, and vacuum drying at 50-60℃ for 4-6 h to obtain the modified boron nitride.

[0015] As optimization, the hydrogen-containing silicone oil in step (4) has a hydrogen content of 0.5 wt%, which is purchased from Shandong Dayi Chemical Co., Ltd.

[0016] As optimization, the platinum content of the platinum catalyst in step (4) is 1000 ppm, which is purchased from Shanghai Siyou New Material Science and Technology Co., Ltd.

[0017] As optimization, the preparation steps of the high-thermal-conductivity filler modified organic silicon pouring sealant in step (4) are as follows: mixing modified polysiloxane, modified boron nitride, hydrogen-containing silicone oil and platinum catalyst uniformly according to a mass ratio of 1: (0.2-0.3): (0.4-0.5): (0.001-0.002), injecting into a mold, vacuum deaerating at room temperature for 20-30 min, and curing at 80-90 DEG C for 10-12 h to obtain the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0018] As optimization, the reaction process of the flame-retardant modified cyclotetrasiloxane is as follows:

[0019] .

[0020] As optimization, the reaction process of the modified boron nitride is as follows:

[0021] .

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] In the preparation of the high-thermal-conductivity filler modified organic silicon pouring sealant, the flame-retardant modified cyclotetrasiloxane is prepared by reacting tetramethyltetravinylcyclotetrasiloxane with 4-(diphenyl phosphine acyl) butanethiol; the hydroxyl-terminated polysiloxane is prepared by reacting the flame-retardant modified cyclotetrasiloxane with trifluoro propyl cyclotetrasiloxane, octamethyl cyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, tetramethyl ammonium hydroxide and deionized water; the modified polysiloxane is prepared by reacting the hydroxyl-terminated polysiloxane with 3-phenyl-7-coumarin isocyanate; the aminated boron nitride is prepared by reacting the hydroxylated boron nitride with 3-aminopropyl triethoxysilane; the modified boron nitride is prepared by reacting the aminated boron nitride with 4-penten aldehyde, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl] propionic acid and isocyanic acid methyl ester; the high-thermal-conductivity filler modified organic silicon pouring sealant is prepared by mixing the modified polysiloxane, the modified boron nitride, the hydrogen-containing silicone oil and the platinum catalyst, injecting into a mold and heat curing.

[0024] Firstly, tetramethyltetavinylcyclotetrasiloxane and 4-(diphenylphosphine) butanethiol undergo mercapto-alkene reaction to generate cyclotetrasiloxane containing phosphorus element. The phosphorus element can interfere with the active group H· in the combustion process, decompose to produce non-combustible gas, slow down the combustion reaction, and also produce phosphoric acid substances with dehydration effect, promote the formation of carbonized layer on the surface of the material, thereby improving the flame retardant performance of the high thermal conductivity filler modified silicone pouring sealant. Mercapto-alkene reaction can also form a sulfide bond, which can absorb ultraviolet light and convert energy into heat energy to release, thereby improving the anti-aging performance of the high thermal conductivity filler modified silicone pouring sealant. The flame-retardant modified cyclotetrasiloxane is reacted with trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, tetramethyltetavinylcyclotetrasiloxane, tetramethylammonium hydroxide and deionized water to obtain a hydroxyl-terminated polysiloxane. The flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane and tetramethyltetavinylcyclotetrasiloxane undergo anionic ring-opening polymerization under the catalysis of tetramethylammonium hydroxide, and deionized water is used as an end-capping agent to prepare a hydroxyl-terminated polysiloxane containing fluorine element, double bond and phosphorus element. Fluorine element has low surface energy, which gives the high thermal conductivity filler modified silicone pouring sealant good super-hydrophobic performance and flame retardant performance. The double bond on the polysiloxane and the double bond of the modified silicon nitride can undergo a silicon-hydrogen reaction with hydrogen-containing silicone oil to form a cross-linked network structure, thereby improving the mechanical properties and thermal conductivity of the high thermal conductivity filler modified silicone pouring sealant. The hydroxyl group on the hydroxyl-terminated polysiloxane reacts with the isocyanate group on 3-phenyl-7-coumarin isocyanate to introduce a coumarin group on the polysiloxane. The coumarin group can absorb ultraviolet light, thereby improving the anti-aging performance of the high thermal conductivity filler modified silicone pouring sealant.

[0025] Secondly, the hydroxylated boron nitride is reacted with 3-aminopropyl triethoxysilane to obtain aminated boron nitride. The boron nitride has good thermal conductivity, flame retardation and mechanical properties. The boron nitride is modified by the silane coupling agent to improve the compatibility of the boron nitride and the matrix, thereby improving the thermal conductivity, flame retardation and mechanical properties of the high-thermal-conductivity filler modified silicone pouring sealant. Meanwhile, the addition of the boron nitride forms a rough structure on the surface of the silicone pouring sealant, thereby endowing the high-thermal-conductivity filler modified silicone pouring sealant with super-hydrophobicity. The aminated boron nitride is subjected to Ugi multi-component reaction with 4-pentenyl aldehyde, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid and methyl isocyanoacetate to introduce double bonds and benzotriazole ultraviolet absorbers on the boron nitride. The benzotriazole ultraviolet absorbers can convert absorbed light energy into heat energy or radiation energy, thereby further improving the anti-aging properties of the high-thermal-conductivity filler modified silicone pouring sealant. Meanwhile, the benzotriazole contains a large amount of nitrogen elements, which can synergistically flame retard with phosphorus elements, thereby further improving the flame retardation of the high-thermal-conductivity filler modified silicone pouring sealant. The double bonds on the modified boron nitride and the double bonds on the modified polysiloxane are subjected to silicon hydrogen reaction with hydrogen-containing silicone oil to form a crosslinked network structure, thereby further improving the mechanical properties and thermal conductivity of the high-thermal-conductivity filler modified silicone pouring sealant. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0027] Embodiment 1

[0028] A preparation method of a high-thermal-conductivity filler modified silicone pouring sealant comprises the following preparation steps:

[0029] (1) Under a nitrogen atmosphere, tetramethyltetravinylcyclotetrasiloxane, 4-(diphenyl phosphinyl) butanethiol and azobisisobutyronitrile are uniformly mixed in a mass ratio of 1:3.5:0.002, and are stirred and reacted at 65°C for 4h. After being cooled to room temperature, 0.8 times the mass of the tetramethyltetravinylcyclotetrasiloxane of cyclohexane is added, and the mixture is washed with a 0.35 mol / L sodium hydroxide aqueous solution for 3 times and distilled water until neutral. The mixture is subjected to vacuum distillation at 50°C for 10h to obtain a flame-retardant modified cyclotetrasiloxane;

[0030] (2) Under the atmosphere of nitrogen, the flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane are mixed uniformly according to the mass ratio of 1:0.3:0.4:0.5, stirred and mixed at 80℃ for 20 min, heated to 105℃, 0.001 times of tetramethylammonium hydroxide of the mass of the flame-retardant modified cyclotetrasiloxane and 0.006 times of deionized water of the mass of the flame-retardant modified cyclotetrasiloxane are added, stirred and reacted for 6 h, heated to 150℃, stirred for 2 h, and distilled under reduced pressure to prepare a hydroxyl-terminated polysiloxane; under the atmosphere of nitrogen, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are mixed uniformly according to the molar ratio of isocyanate group to hydroxyl group of 1:1, 0.002 times of dibutyltin dilaurate of the mass of the 3-phenyl-7-coumarin isocyanate and 15 times of N,N-dimethylformamide of the mass of the 3-phenyl-7-coumarin isocyanate are added, stirred and reacted at 80℃ for 6 h, and N,N-dimethylformamide is removed by distillation under reduced pressure to prepare a modified polysiloxane;

[0031] (3) Hydroxylated boron nitride and 98wt% ethanol aqueous solution are mixed uniformly according to the mass ratio of 1:10, 0.06 times of 3-aminopropyl triethoxysilane of the mass of the hydroxylated boron nitride is added, ultrasonic dispersion is performed for 20 min, stirred and reacted at 80℃ for 6 h, centrifugal separation is performed, the obtained precipitate is washed with anhydrous ethanol for 3 times, vacuum drying is performed at 50℃ for 4 h to prepare aminated boron nitride; the aminated boron nitride, 4-pentenal, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanacetate, N,N-dimethylformamide are mixed uniformly according to the mass ratio of 1:0.02:0.1:0.025:10, stirred and reacted at room temperature for 10 h, centrifugal separation is performed, the obtained precipitate is washed with anhydrous ethanol for 3 times, vacuum drying is performed at 50℃ for 4 h to prepare a modified boron nitride;

[0032] (4) The modified polysiloxane, the modified boron nitride, hydrogen-containing silicone oil and platinum catalyst are mixed uniformly according to the mass ratio of 1:0.2:0.4:0.001, injected into a mold, vacuum debubbling is performed at room temperature for 20 min, and curing is performed at 80℃ for 10 h to prepare a high-thermal-conductivity filler modified silicone potting adhesive.

[0033] Example 2

[0034] A preparation method of a high-thermal-conductivity filler modified silicone potting adhesive, comprising the following preparation steps:

[0035] (1) Under nitrogen atmosphere, tetramethyltetavinylcyclotetrasiloxane, 4-(diphenylphosphinyl)butanethiol, azobis isobutyronitrile were mixed uniformly in a mass ratio of 1:3.8:0.003, stirred and reacted at 70°C for 5h, cooled to room temperature, 1 times mass of cyclohexane of tetramethyltetavinylcyclotetrasiloxane was added, washed with 0.35 mol / L sodium hydroxide aqueous solution for 4 times, washed with distilled water until neutral, distilled under reduced pressure, dried at 55°C under vacuum for 11h, to obtain flame-retardant modified cyclotetrasiloxane;

[0036] (2) Under nitrogen atmosphere, flame-retardant modified cyclotetrasiloxane, trifluoropropylcyclotetrasiloxane, octamethylcyclotetrasiloxane, tetramethyltetavinylcyclotetrasiloxane were mixed uniformly in a mass ratio of 1:0.35:0.45:0.55, stirred and mixed at 85°C for 30min, heated to 108°C, 0.0015 times mass of tetramethylammonium hydroxide of flame-retardant modified cyclotetrasiloxane was added, 0.007 times mass of deionized water of flame-retardant modified cyclotetrasiloxane was added, stirred and reacted for 7h, heated to 155°C, stirred for 2.5h, distilled under reduced pressure, to obtain hydroxyl-terminated polysiloxane; under nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate, hydroxyl-terminated polysiloxane were mixed uniformly in a molar ratio of isocyanate group to hydroxyl group of 1:1.01, 0.003 times mass of dibutyltin dilaurate of 3-phenyl-7-coumarin isocyanate was added, 18 times mass of N,N-dimethylformamide of 3-phenyl-7-coumarin isocyanate was added, stirred and reacted at 85°C for 7h, distilled under reduced pressure to remove N,N-dimethylformamide, to obtain modified polysiloxane;

[0037] (3) Hydroxylated boron nitride, 98wt% ethanol aqueous solution were mixed uniformly in a mass ratio of 1:11, 0.07 times mass of 3-aminopropyltriethoxysilane of hydroxylated boron nitride was added, ultrasonic dispersed for 25min, stirred and reacted at 80°C for 7h, centrifuged, the obtained precipitate was washed with anhydrous ethanol for 4 times, dried at 55°C under vacuum for 5h, to obtain aminated boron nitride; aminated boron nitride, 4-pentenal, 3-[3-(benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanacetate, N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:0.025:0.11:0.025:10, stirred and reacted at room temperature for 11h, centrifuged, the obtained precipitate was washed with anhydrous ethanol for 4 times, dried at 55°C under vacuum for 5h, to obtain modified boron nitride;

[0038] (4) Modified polysiloxane, modified boron nitride, hydrogen-containing silicone oil, platinum catalyst were mixed uniformly in a mass ratio of 1:0.25:0.45:0.0015, injected into a mold, vacuum degassing at room temperature for 25min, cured at 85°C for 11h, to obtain high-thermal-conductivity filler modified silicone potting sealant.

[0039] Example 3

[0040] A preparation method of a high-thermal-conductivity filler modified silicone pouring sealant, comprising the following preparation steps:

[0041] (1) Under a nitrogen atmosphere, tetramethyltetavinylcyclotetrasiloxane, 4-(diphenyl phosphine) butanethiol, and azobis isobutyronitrile are uniformly mixed in a mass ratio of 1:4:0.004, stirred and reacted at 75°C for 6h, cooled to room temperature, 1.2 times the mass of tetramethyltetavinylcyclotetrasiloxane of cyclohexane is added, washed with 0.35 mol / L sodium hydroxide aqueous solution for 5 times, washed with distilled water until neutral, distilled under reduced pressure, and dried at 60°C under vacuum for 12h to obtain a flame-retardant modified cyclotetrasiloxane;

[0042] (2) Under a nitrogen atmosphere, the flame-retardant modified cyclotetrasiloxane, trifluoropropylcyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetavinylcyclotetrasiloxane are uniformly mixed in a mass ratio of 1:0.4:0.5:0.6, stirred and mixed at 90°C for 40min, heated to 110°C, 0.002 times the mass of the flame-retardant modified cyclotetrasiloxane of tetramethylammonium hydroxide and 0.008 times the mass of the flame-retardant modified cyclotetrasiloxane of deionized water are added, stirred and reacted for 8h, heated to 160°C, stirred for 3h, distilled under reduced pressure, to obtain a hydroxyl-terminated polysiloxane; under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are uniformly mixed in a molar ratio of isocyanate group to hydroxyl group of 1:1.02, 0.004 times the mass of the 3-phenyl-7-coumarin isocyanate of dibutyltin dilaurate and 20 times the mass of the 3-phenyl-7-coumarin isocyanate of N,N-dimethylformamide are added, stirred and reacted at 90°C for 8h, N,N-dimethylformamide is removed by distillation under reduced pressure, to obtain a modified polysiloxane;

[0043] (3) Hydroxylated boron nitride and 98wt% ethanol aqueous solution are uniformly mixed in a mass ratio of 1:12, 0.08 times the mass of the hydroxylated boron nitride of 3-aminopropyl triethoxysilane is added, ultrasonic dispersed for 30min, stirred and reacted at 80°C for 8h, centrifuged, the obtained precipitate is washed with anhydrous ethanol for 5 times, and dried at 60°C under vacuum for 6h to obtain aminated boron nitride; the aminated boron nitride, 4-pentenal, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanacetate, and N,N-dimethylformamide are uniformly mixed in a mass ratio of 1:0.03:0.12:0.035:12, stirred and reacted at room temperature for 12h, centrifuged, the obtained precipitate is washed with anhydrous ethanol for 5 times, and dried at 60°C under vacuum for 6h to obtain a modified boron nitride;

[0044] (4) The modified polysiloxane, modified boron nitride, hydrogen-containing silicone oil, platinum catalyst were mixed uniformly according to the mass ratio of 1:0.3:0.5:0.002, injected into a mold, vacuum degassing at room temperature for 30 min, and cured at 90°C for 12 h to obtain a high-thermal-conductivity filler modified silicone potting sealant.

[0045] Comparative Example 1

[0046] The preparation method of a high-thermal-conductivity filler modified silicone potting sealant of Comparative Example 1 is different from that of Example 2 in that step (3) is modified as follows: the hydroxylated boron nitride and 98wt% ethanol aqueous solution were mixed uniformly according to the mass ratio of 1:11, 0.07 times the mass of the hydroxylated boron nitride was added with 3-aminopropyl triethoxysilane, ultrasonic dispersion was performed for 25 min, stirring reaction was performed at 80°C for 7 h, centrifugal separation was performed, the obtained precipitate was washed with anhydrous ethanol for 4 times, and vacuum drying was performed at 55°C for 5 h to obtain the modified boron nitride. The remaining steps are the same as those of Example 2.

[0047] Comparative Example 2

[0048] The preparation method of a high-thermal-conductivity filler modified silicone potting sealant of Comparative Example 2 is different from that of Example 2 in that step (3) is not performed, and step (4) is modified as follows: the modified polysiloxane, hydroxylated boron nitride, hydrogen-containing silicone oil, platinum catalyst were mixed uniformly according to the mass ratio of 1:0.25:0.45:0.0015, injected into a mold, vacuum degassing at room temperature for 25 min, and cured at 85°C for 11 h to obtain a high-thermal-conductivity filler modified silicone potting sealant. The remaining steps are the same as those of Example 2.

[0049] Comparative Example 3

[0050] The preparation method of a high-thermal-conductivity filler modified silicone potting sealant of Comparative Example 3 is different from that of Example 2 in that step (3) is not performed, and step (4) is modified as follows: the modified polysiloxane, hydrogen-containing silicone oil, platinum catalyst were mixed uniformly according to the mass ratio of 1:0.25:0.45:0.0015, injected into a mold, vacuum degassing at room temperature for 25 min, and cured at 85°C for 11 h to obtain a high-thermal-conductivity filler modified silicone potting sealant. The remaining steps are the same as those of Example 2.

[0051] Comparative Example 4

[0052] The preparation method of the high-thermal-conductivity filler modified silicone potting adhesive of Comparative Example 4 is different from that of Example 2 in that step (2) is modified. In step (2), the flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are mixed in a mass ratio of 1:0.35:0.45:0.55, stirred and mixed at 85°C for 30 min, heated to 108°C, 0.0015 times the mass of the flame-retardant modified cyclotetrasiloxane of tetramethylammonium hydroxide is added, 0.007 times the mass of the flame-retardant modified cyclotetrasiloxane of deionized water is added, stirred and reacted for 7 h, heated to 155°C, stirred for 2.5 h, and distilled under reduced pressure to obtain the modified polysiloxane. The remaining steps are the same as those of Example 2.

[0053] Comparative Example 5

[0054] The preparation method of the high-thermal-conductivity filler modified silicone potting adhesive of Comparative Example 5 is different from that of Example 2 in that step (2) is modified. In step (2), the flame-retardant modified cyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are mixed in a mass ratio of 1:0.45:0.55, stirred and mixed at 85°C for 30 min, heated to 108°C, 0.0015 times the mass of the flame-retardant modified cyclotetrasiloxane of tetramethylammonium hydroxide is added, 0.007 times the mass of the flame-retardant modified cyclotetrasiloxane of deionized water is added, stirred and reacted for 7 h, heated to 155°C, stirred for 2.5 h, and distilled under reduced pressure to obtain the hydroxyl-terminated polysiloxane; under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are mixed uniformly in a molar ratio of isocyanate group to hydroxyl group of 1:1.01, 0.003 times the mass of 3-phenyl-7-coumarin isocyanate of dibutyltin dilaurate is added, 18 times the mass of 3-phenyl-7-coumarin isocyanate of N,N-dimethylformamide is added, stirred and reacted at 85°C for 7 h, N,N-dimethylformamide is removed by distillation under reduced pressure, and the modified polysiloxane is obtained. The remaining steps are the same as those of Example 2.

[0055] Comparative Example 6

[0056] The preparation method of the high thermal conductive filler modified silicone potting adhesive of Comparative Example 6 is different from that of Example 2 in that step (2) is modified. In step (2), under a nitrogen atmosphere, flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, and octamethylcyclotetrasiloxane are uniformly mixed in a mass ratio of 1:0.35:0.45, stirred and mixed at 85°C for 30 min, heated to 108°C, 0.0015 times the mass of the flame-retardant modified cyclotetrasiloxane is added to tetramethylammonium hydroxide, 0.007 times the mass of the flame-retardant modified cyclotetrasiloxane is added to deionized water, stirred for 7 h, heated to 155°C, stirred for 2.5 h, and distilled under reduced pressure to obtain a hydroxyl-terminated polysiloxane. Under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are uniformly mixed in a molar ratio of isocyanate group to hydroxyl group of 1:1.01, 0.003 times the mass of the 3-phenyl-7-coumarin isocyanate is added to dibutyltin dilaurate, 18 times the mass of the 3-phenyl-7-coumarin isocyanate is added to N,N-dimethylformamide, stirred and reacted at 85°C for 7 h, and N,N-dimethylformamide is removed by distillation under reduced pressure to obtain a modified polysiloxane. The remaining steps are the same as in Example 2.

[0057] Comparative Example 7

[0058] The preparation method of the high thermal conductive filler modified silicone potting adhesive of Comparative Example 7 is different from that of Example 2 in that step (1) is not performed. In step (2), under a nitrogen atmosphere, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are uniformly mixed in a mass ratio of 0.35:0.45:0.55, stirred and mixed at 85°C for 30 min, heated to 108°C, 0.000675 times the mass of the octamethylcyclotetrasiloxane is added to tetramethylammonium hydroxide, 0.00315 times the mass of the octamethylcyclotetrasiloxane is added to deionized water, stirred for 7 h, heated to 155°C, stirred for 2.5 h, and distilled under reduced pressure to obtain a hydroxyl-terminated polysiloxane. Under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and the hydroxyl-terminated polysiloxane are uniformly mixed in a molar ratio of isocyanate group to hydroxyl group of 1:1.01, 0.003 times the mass of the 3-phenyl-7-coumarin isocyanate is added to dibutyltin dilaurate, 18 times the mass of the 3-phenyl-7-coumarin isocyanate is added to N,N-dimethylformamide, stirred and reacted at 85°C for 7 h, and N,N-dimethylformamide is removed by distillation under reduced pressure to obtain a modified polysiloxane. The remaining steps are the same as in Example 2.

[0059] Test Example 1

[0060] Thermal conductivity test:

[0061] The high-thermal-conductivity filler modified silicone pouring sealant prepared in each example and the comparative examples was tested for thermal conductivity by using a laser thermal conductivity instrument LFA according to GB / T11205-2009 Rubber Determination of Thermal Conductivity Hot-Wire Method.

[0062] The results are shown in Table 1.

[0063] Table 1

[0064] Thermal conductivity [W / (m-K)] Thermal conductivity [W / (m-K)] Example 1 0.751 Comparative Example 1 0.607 Example 2 0.754 Comparative Example 2 0.423 Example 3 0.756 Comparative Example 3 0.258 Comparative Example 4 0.748 Comparative Example 5 0.741 Comparative Example 6 0.593 Comparative Example 7 0.745

[0065] As can be seen from the experimental data of Examples 1-3 and Comparative Examples 1-7 in Table 1, the high-thermal-conductivity filler modified silicone pouring sealant prepared in the application has good thermal conductivity.

[0066] By comparison, the thermal conductivity of Examples 1-3 is greater than that of Comparative Examples 1-3 and Comparative Example 6, which shows that boron nitride has good thermal conductivity performance, and modification by the silane coupling agent improves the compatibility of boron nitride with the matrix, thereby improving the thermal conductivity of the high-thermal-conductivity filler modified silicone pouring sealant; the double bonds on the modified boron nitride and the double bonds on the modified polysiloxane react with hydrogen-containing silicone oil to form a crosslinked network structure, further improving the thermal conductivity of the high-thermal-conductivity filler modified silicone pouring sealant.

[0067] Test Example 2

[0068] Flame Retardant Performance Test:

[0069] The high-thermal-conductivity filler modified silicone pouring sealant prepared in each example and the comparative examples was tested for limiting oxygen index by using an oxygen index instrument according to the standard of ASTM D2863, with a sample size of 120mm x 6.5mm x 3.2mm, 5 tests for each group, and the average value was calculated.

[0070] The results are shown in Table 2.

[0071] Table 2

[0072] Limiting oxygen index Limiting oxygen index Example 1 31.2% Comparative Example 1 28.7% Example 2 31.5% Comparative Example 2 28.4% Example 3 31.4% Comparative Example 3 26.9% Comparative Example 4 31.0% Comparative Example 5 27.3% Comparative Example 6 31.1% Comparative Example 7 25.6%

[0073] As can be seen from the experimental data of Examples 1-3 and Comparative Examples 1-7 in Table 2, the high-thermal-conductivity filler modified silicone pouring sealant prepared in the application has good flame retardant performance.

[0074] By comparison, the limiting oxygen index of examples 1~3 is greater than that of comparative examples 1~3, which indicates that boron nitride has good flame retardant performance, and the modification of boron nitride by silane coupling agent improves the compatibility of boron nitride with the matrix, thereby improving the flame retardant performance of the high-thermal-conductivity filler modified organic silicon pouring sealant; the Ugi multi-component reaction of aminoboron nitride with 4-pentenyl aldehyde, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid and methyl isocyanacetate introduces benzotriazole ultraviolet absorber on boron nitride, and the benzotriazole contains a large amount of nitrogen element, which synergistically retards flame with phosphorus element, thereby further improving the flame retardant performance of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0075] By comparison, the limiting oxygen index of examples 1~3 is greater than that of comparative example 5, which indicates that the flame-retardant modified cyclotetrasiloxane, trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane and tetramethyltetravinylcyclotetrasiloxane are subjected to an anionic ring-opening polymerization reaction under the catalysis of tetramethylammonium hydroxide, and deionized water is used as an end-capping agent to prepare fluorine-containing hydroxyl-terminated polysiloxane, and the fluorine element has good flame retardant performance, thereby giving the high-thermal-conductivity filler modified organic silicon pouring sealant good flame retardant performance.

[0076] By comparison, the limiting oxygen index of examples 1~3 is greater than that of comparative example 7, which indicates that tetramethyltetravinylcyclotetrasiloxane and 4-(diphenylphosphine) butanethiol are subjected to a mercapto-alkene reaction to generate cyclotetrasiloxane containing phosphorus element, the phosphorus element can interfere with the active group H· in the combustion process, decompose to generate non-combustible gas, slow down the combustion reaction, and also generate phosphoric acid substances with dehydration effect, thereby promoting the formation of a carbonized layer on the surface of the material, and thereby improving the flame retardant performance of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0077] Test example 3

[0078] Superhydrophobic performance test:

[0079] At room temperature, the contact angle of the high-thermal-conductivity filler modified organic silicon pouring sealant prepared in each example and comparative example is measured by using a contact angle tester, the volume of water is 2 μL, each group is tested 5 times, and the average value is calculated.

[0080] The results are shown in Table 3.

[0081] Table 3

[0082] Contact angle Contact angle Example 1 162.2° Comparative Example 1 158.1° Example 2 162.5° Comparative Example 2 154.8° Example 3 162.3° Comparative Example 3 127.3° Comparative Example 4 157.9° Comparative Example 5 139.6° Comparative Example 6 157.3° Comparative Example 7 157.5°

[0083] As can be seen from the experimental data of examples 1~3 and comparative examples 1~7 in Table 3, the high-thermal-conductivity filler modified organic silicon pouring sealant prepared in the present application has good superhydrophobic performance.

[0084] By comparison, the contact angle of examples 1-3 is greater than that of comparative example 3, which indicates that the addition of boron nitride forms a rough structure on the surface of the silicone potting adhesive, thereby imparting the high-thermal-conductivity filler modified silicone potting adhesive with superhydrophobic properties.

[0085] By comparison, the contact angle of examples 1-3 is greater than that of comparative example 5, which indicates that the flame-retardant modified cyclotetrasiloxane and the trifluoropropyl cyclotetrasiloxane, octamethylcyclotetrasiloxane and tetramethyltetravinylcyclotetrasiloxane undergo an anionic ring-opening polymerization reaction under the catalysis of tetramethylammonium hydroxide, and deionized water is used as an end-capping agent to prepare a fluorine-containing hydroxyl-terminated polysiloxane. Fluorine has a low surface energy, and the high-thermal-conductivity filler modified silicone potting adhesive has good superhydrophobic properties.

[0086] Test example 4

[0087] Mechanical property and anti-aging performance test:

[0088] Mechanical property test method: the high-thermal-conductivity filler modified silicone potting adhesive obtained in each example and the comparative examples are respectively prepared into a test sample with a size of 10mmx4mmx1mm, and the tensile strength M is tested by an Instron 5567 universal electronic tensile testing machine at a tensile rate of 200mm / min at room temperature, each test sample is tested 3 times, and the average value is calculated.

[0089] Anti-aging performance test method: the high-thermal-conductivity filler modified silicone potting adhesive obtained in each example and the comparative examples are respectively prepared into a test sample with a size of 10mmx4mmx1mm, and the tensile strength N is tested after the test sample is placed in an ultraviolet aging test box for 360h, the lamp tube is SANKYODENKI 15W UV-B, the lamp tube light intensity is 0.3mW / cm 2 , and the wavelength range of the lamp tube is 280-360nm.

[0090] The results are shown in Table 4.

[0091] Table 4

[0092] Tensile strength (MPa) Performance reduction rate Example 1 1.134 1.27% Example 2 1.140 1.25% Example 3 1.138 1.26% Comparative Example 1 0.973 4.36% Comparative Example 2 0.762 4.53% Comparative Example 3 0.648 4.58% Comparative Example 4 1.132 5.24% Comparative Example 5 1.131 1.34% Comparative Example 6 0.964 1.31% Comparative Example 7 1.133 2.84%

[0093] As can be seen from the experimental data of examples 1-3 and comparative examples 1-7 in Table 4, the high-thermal-conductivity filler modified silicone potting adhesive prepared by the present application has good mechanical properties and anti-aging performance.

[0094] By comparison, the tensile strength of examples 1~3 is greater than that of comparative examples 1~3, comparative example 6, which indicates that boron nitride has good mechanical properties, and the compatibility of boron nitride with the matrix is improved by modifying it with a silane coupling agent, thereby improving the mechanical properties of the high-thermal-conductivity filler modified organic silicon pouring sealant; the double bonds on the modified boron nitride and the double bonds on the modified polysiloxane react with hydrogen-containing silicone oil to form a crosslinked network structure, further improving the mechanical properties of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0095] By comparison, the performance degradation rate of examples 1~3 is less than that of comparative examples 1~3, which indicates that the Ugi multi-component reaction of aminated boron nitride with 4-pentenyl aldehyde, 3-[3-(benzotriazole-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, and methyl isocyanate occurs on the boron nitride, introducing a benzotriazole ultraviolet absorber, which can convert absorbed light energy into heat or radiation energy, thereby further improving the anti-aging properties of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0096] By comparison, the performance degradation rate of examples 1~3 is less than that of comparative example 4, which indicates that the reaction of the hydroxyl groups on the hydroxyl-terminated polysiloxane with the isocyanate groups on 3-phenyl-7-coumarin isocyanate introduces a coumarin group on the polysiloxane, which can absorb ultraviolet light, thereby improving the anti-aging properties of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0097] By comparison, the performance degradation rate of examples 1~3 is less than that of comparative example 7, which indicates that the thiol-ene reaction of tetramethyltetravinylcyclotetrasiloxane with 4-(diphenylphosphine)butanethiol forms a thioether bond, which can absorb ultraviolet light and convert the energy into heat energy, and cooperates with coumarin and benzotriazole to further improve the anti-aging properties of the high-thermal-conductivity filler modified organic silicon pouring sealant.

[0098] The above specific embodiments further illustrate the purpose, technical solutions, and beneficial effects of the present application, and it should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the protection scope of the present application, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing a high thermal conductivity filler-modified silicone potting compound, characterized in that, The preparation steps include the following: (1) Under a nitrogen atmosphere, tetramethyltetravinylcyclotetrasiloxane, 4-(diphenylphosphono)butyritol and azobisisobutyronitrile were mixed evenly and stirred at 65~75℃ for 4~6h. After cooling to room temperature, cyclohexane was added, washed, vacuum distilled and dried to obtain flame-retardant modified cyclotetrasiloxane. (2) Under a nitrogen atmosphere, flame-retardant modified cyclotetrasiloxane, trifluoropropylcyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are mixed evenly and stirred at 80-90℃ for 20-40 min. The temperature is raised to 105-110℃, tetramethylammonium hydroxide and deionized water are added, and the mixture is stirred for 6-8 h. The temperature is raised to 150-160℃ and stirred for 2-3 h. The mixture is then distilled under reduced pressure to obtain hydroxyl-terminated polysiloxane. Under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and hydroxyl-terminated polysiloxane are mixed evenly according to the molar ratio of isocyanate group to hydroxyl group of 1: (1-1.02). Dibutyltin dilaurate and N,N-dimethylformamide are added, and the mixture is stirred at 80-90℃ for 6-8 h. The mixture is then distilled under reduced pressure to obtain modified polysiloxane. (3) Hydroxylated boron nitride and 98wt% ethanol aqueous solution are mixed evenly, 3-aminopropyltriethoxysilane is added, ultrasonic dispersion is carried out, and the mixture is stirred at 80℃ for 6-8h. After centrifugation, washing and drying are performed to obtain aminolated boron nitride; aminolated boron nitride, 4-pentenal, 3-[3-(benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanate, and N,N-dimethylformamide are mixed evenly, and the mixture is stirred at room temperature for 10-12h. After centrifugation, washing and drying are performed to obtain modified boron nitride; (4) Mix the modified polysiloxane, modified boron nitride, hydrogen-containing silicone oil and platinum catalyst evenly, inject into the mold, remove bubbles under vacuum at room temperature, and cure at 80~90℃ for 10~12h to obtain high thermal conductivity filler modified organosilicon potting compound.

2. The preparation method of a high thermal conductivity filler-modified organosilicon potting compound according to claim 1, characterized in that, The preparation steps of the flame-retardant modified cyclotetrasiloxane in step (1) are as follows: under a nitrogen atmosphere, tetramethyltetravinylcyclotetrasiloxane, 4-(diphenylphosphono)butyritin and azobisisobutyronitrile are mixed evenly in a mass ratio of 1:(3.5~4):(0.002~0.004), stirred and reacted at 65~75℃ for 4~6h, cooled to room temperature, and cyclohexane of 0.8~1.2 times the mass of tetramethyltetravinylcyclotetrasiloxane is added. The mixture is washed 3~5 times with 0.35mol / L sodium hydroxide aqueous solution, washed with distilled water until neutral, distilled under reduced pressure, and dried under vacuum at 50~60℃ for 10~12h to obtain the flame-retardant modified cyclotetrasiloxane.

3. The preparation method of a high thermal conductivity filler-modified organosilicon potting compound according to claim 1, characterized in that, The preparation steps of the modified polysiloxane in step (2) are as follows: Under a nitrogen atmosphere, flame-retardant modified cyclotetrasiloxane, trifluoropropylcyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are mixed evenly at a mass ratio of 1:(0.3~0.4):(0.4~0.5):(0.5~0.6), stirred and mixed at 80~90℃ for 20~40 min, heated to 105~110℃, and added 0.001~0.002 times the mass of flame-retardant modified cyclotetrasiloxane tetramethylammonium hydroxide and 0.006~0.008 times the mass of flame-retardant modified cyclotetrasiloxane deionized water. The mixture is stirred and reacted for 6~8 h. The mixture was heated to 150-160℃ and stirred for 2-3 hours, then distilled under reduced pressure to obtain hydroxyl-terminated polysiloxane. Under a nitrogen atmosphere, 3-phenyl-7-coumarin isocyanate and hydroxyl-terminated polysiloxane were mixed evenly at a molar ratio of isocyanate group to hydroxyl group of 1:(1-1.02). 0.002-0.004 times the mass of 3-phenyl-7-coumarin isocyanate dibutyltin dilaurate and 15-20 times the mass of 3-phenyl-7-coumarin isocyanate N,N-dimethylformamide were added. The mixture was stirred at 80-90℃ for 6-8 hours, and N,N-dimethylformamide was removed by reduced pressure distillation to obtain modified polysiloxane.

4. The preparation method of a high thermal conductivity filler-modified organosilicon potting compound according to claim 1, characterized in that, The hydroxylated boron nitride in step (3) is hydroxylated boron nitride nanosheets with a diameter of 0.1~0.4μm.

5. The preparation method of a high thermal conductivity filler-modified silicone potting compound according to claim 1, characterized in that, The preparation steps of the modified boron nitride in step (3) are as follows: Hydroxylated boron nitride and 98wt% ethanol aqueous solution are mixed evenly at a mass ratio of 1:(10~12), and 0.06~0.08 times the mass of hydroxylated boron nitride with 3-aminopropyltriethoxysilane is added. The mixture is ultrasonically dispersed for 20~30 min, stirred at 80℃ for 6~8 h, centrifuged, and the resulting precipitate is washed 3~5 times with anhydrous ethanol and vacuum dried at 50~60℃ for 4~6 h to obtain aminolated boron nitride; aminolated boron nitride, 4- Pentenal, 3-[3-(benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl isocyanate, and N,N-dimethylformamide were mixed in a mass ratio of 1:(0.02~0.03):(0.1~0.12):(0.025~0.035):(10~12) until homogeneous. The mixture was stirred and reacted at room temperature for 10~12 h. After centrifugation, the precipitate was washed 3~5 times with anhydrous ethanol and dried under vacuum at 50~60℃ for 4~6 h to obtain modified boron nitride.

6. The preparation method of a high thermal conductivity filler-modified silicone potting compound according to claim 1, characterized in that, The hydrogen content of the hydrogen-containing silicone oil in step (4) is 0.5 wt%.

7. The preparation method of a high thermal conductivity filler-modified silicone potting compound according to claim 1, characterized in that, The platinum catalyst in step (4) has a platinum content of 1000 ppm.

8. The preparation method of a high thermal conductivity filler-modified organosilicon potting compound according to claim 1, characterized in that, The preparation steps of the high thermal conductivity filler modified silicone potting compound in step (4) are as follows: the modified polysiloxane, modified boron nitride, hydrogen-containing silicone oil and platinum catalyst are mixed evenly in a mass ratio of 1: (0.2~0.3): (0.4~0.5): (0.001~0.002), injected into the mold, vacuum defoamed at room temperature for 20~30 min, and cured at 80~90℃ for 10~12 h to obtain the high thermal conductivity filler modified silicone potting compound.