A thermally conductive and insulating liquid silicone rubber, its preparation method and application

Abstract

The present application relates to the field of silicone rubber technology, and specifically discloses a thermally conductive insulating liquid silicone rubber and its preparation method and application. A thermally conductive insulating liquid silicone rubber includes dimethyl vinyl silicone rubber, terminal hydroxyl silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler and 5-7 parts of titanate coupling agent; its preparation method includes mixing and vulcanization. The thermally conductive insulating liquid silicone rubber of the present application can be used in the preparation of thermal interface materials, which has good mechanical properties and aging resistance, and has good insulation and thermal conductivity, and can meet the heat dissipation and application requirements of high-power electronic devices.

Description

Technical Field

[0001] The present application relates to the technical field of silicone rubber, and more specifically, to a thermally conductive insulating liquid silicone rubber and a preparation method and application thereof. Background Art

[0002] At present, the circuit design of electronic products is becoming more and more complex, showing a trend of density and miniaturization. These electronic and electrical equipment will generate a lot of heat. If this heat cannot be discharged in time, it will accumulate to a certain extent and will inevitably cause damage to the components and equipment of the electronic and electrical equipment. Therefore, the excess heat generated must be transferred to the surrounding environment in a timely and effective manner. In the heat dissipation industry, traditional metal materials are greatly restricted by the geometric shape of their products, and there is a certain gap between such heat dissipation devices and the surface of electronic components, so they are increasingly being replaced by some thermal interface materials.

[0003] Thermally conductive rubber is a type of rubber-based composite material that focuses on thermal conductivity. It is mostly based on silicone rubber and has the characteristics of good elasticity, good electrical insulation, easy deformation under low pressure, and good sealing. When used for heat dissipation of components, it can effectively fill the gaps between interfaces and drive away the air between the hot and cold interfaces, which can improve the efficiency of the radiator by about 40%. Therefore, the study of thermally conductive rubber with high thermal conductivity is of great significance to the miniaturization and density of electronic and electrical equipment, as well as to improve their precision and lifespan.

[0004] At present, the thermal conductive fillers used in common thermal conductive silicone rubber composite materials are mostly metal powders such as silver and aluminum, in addition to alumina, silicon carbide, quartz powder, etc. The cost of using the above thermal conductive powders is relatively high, and the thermal conductivity of the thermal conductive silicone rubber obtained is not well improved, and the overall performance is relatively poor. Summary of the invention

[0005] In order to improve the thermal conductivity and insulation performance of silicone rubber, the present application provides a thermally conductive and insulating liquid silicone rubber and a preparation method and application thereof.

[0006] In a first aspect, the present application provides a thermally conductive insulating liquid silicone rubber, which adopts the following technical solution:

[0007] A thermally conductive insulating liquid silicone rubber comprises the following raw materials in parts by weight:

[0008] 100 parts of dimethyl vinyl silicone rubber;

[0009] 8-15 parts of hydroxyl-terminated silicone oil;

[0010] 10-20 parts of liquid crystal polymer;

[0011] 10-15 parts of hexagonal boron nitride;

[0012] 50-70 parts of modified graphene-based filler;

[0013] 1-3 parts of vulcanizing agent;

[0014] 5-7 parts of titanate coupling agent;

[0015] The modified graphene-based filler is obtained by loading zinc oxide particles on the graphene-based filler.

[0016] By adopting the above technical scheme, hexagonal boron nitride and modified graphene-based fillers are compounded and used as thermally conductive fillers. Hexagonal boron nitride and modified graphene-based fillers can form a three-dimensional cross-linked thermally conductive network in silicone rubber, thereby improving the thermal conductivity of silicone rubber. After loading zinc oxide particles, the modified graphene-based filler can increase the number of thermal conductive pathways in silicone rubber. Compared with a single graphene filler, the modified graphene-based filler is easier to increase the filling density, form a dense stack, improve thermal conductivity, and the thermal resistance has a positive temperature coefficient, thereby effectively improving the thermal conductivity of silicone rubber.

[0017] By adding liquid crystal polymer, the coverage area and extension path of the heat conduction network in the silicone rubber can be further improved through the liquid crystal polymer, thereby greatly enhancing the thermal conductivity of the silicone rubber, and the liquid crystal polymer has good insulation performance. The liquid crystal polymer can enter the interlayer structure of graphene, thereby reducing the conductivity of graphene. Embedding the liquid crystal polymer in the heat conduction network can effectively enhance the insulation of the heat conduction network, thereby improving the insulation performance of the silicone rubber. The liquid silicone rubber prepared from the above raw materials has good mechanical properties and aging resistance, and has good insulation and thermal conductivity, which can meet the heat dissipation and application requirements of high-power electronic devices.

[0018] Optionally, the graphene-based filler is a reduced graphene oxide filler.

[0019] By adopting the above technical scheme, the reduced graphene oxide contains a large number of oxygen-containing functional groups, thus giving the reduced graphene oxide good dispersibility and reactivity, which is beneficial to the uniform dispersion of the reduced graphene oxide in the silicone rubber, and further beneficial to the formation of a three-dimensional cross-linked thermal conductive network with a uniform and stable structure inside the silicone rubber, which is beneficial to improving the thermal conductivity of the silicone rubber.

[0020] Optionally, the modified graphene-based filler is prepared by a method comprising the following steps:

[0021] S1: Mix the reduced graphene oxide powder and the zinc oxide colloidal solution, raise the temperature to 60-70° C., and then stir at a constant temperature for 1-1.5 hours to obtain a mixed solution;

[0022] S2: Add a β-alanine solution with a mass concentration of 20-25% to the mixed solution, then heat it to 60-70° C., stir it at a constant temperature for 2-3 hours, and obtain a modified graphene-based filler after filtering and calcining.

[0023] By adopting the above technical scheme, during the reaction process, the oxygen-containing functional groups on the surface of the reduced graphene oxide can react with β-alanine containing amino and carboxyl groups, so that a stable covalent bond is formed between the reduced graphene oxide and the β-alanine crystals. In addition, since there is an N atom and a pair of unshared electrons in the β-alanine molecule, it is easy to form a covalent bond with the residual Zn2+, thereby complexing with Zn2+ to form a relatively stable complex, thereby improving the stability of the zinc oxide particles loaded on the reduced graphene oxide, which is conducive to the modified graphene-based filler to exert the best thermal conductivity and insulation effect.

[0024] Optionally, the mass ratio of reduced graphene oxide powder to zinc oxide colloidal solution in S1 is 1:(1-1.5); the mass ratio of the mixed solution to β-alanine solution in S2 is 1:(0.3-0.5).

[0025] By adopting the above technical scheme and selecting the raw materials in the above ratio to prepare the modified graphene-based filler, it is beneficial to load a layer of evenly dispersed zinc oxide particles on the surface of the reduced graphene oxide, so that the modified graphene-based filler can exert better thermal conductivity and insulation effects.

[0026] Optionally, the zinc oxide colloidal solution is prepared by the following method: dissolving zinc acetate solution in glycerol ether, stirring for 20-30 minutes, then adding ethylenediamine in an amount equal to the molar number of the zinc acetate solution, and stirring at a constant temperature of 70-80° C. for 0.5-1 hour to obtain the zinc oxide colloidal solution.

[0027] By adopting the above technical solution, the prepared zinc oxide colloidal solution has the advantages of good dispersibility and uniform distribution. No waste gas and waste liquid are generated in the above preparation process, which is beneficial to improving the environmental protection of the production process.

[0028] Optionally, the molecular weight of the terminal hydroxyl silicone oil is 15,000-20,000, and the hydroxyl content is 0.17-0.23%.

[0029] In a second aspect, the present application provides a method for preparing a thermally conductive insulating liquid silicone rubber, using the following technical solution:

[0030] A method for preparing a thermally conductive insulating liquid silicone rubber comprises the following steps:

[0031] Step 1: Mixing: Mix dimethyl vinyl silicone rubber, hydroxyl-terminated silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler, vulcanizer and titanate coupling agent according to the ratio and mix them on a mixer. After mixing evenly, place them at room temperature for 6-8 hours to obtain a mixed rubber;

[0032] Step 2: Vulcanization: The mixed rubber obtained in step 1 is vulcanized at 170-180° C. and 6-8 MPa for 10-20 min, and then cooled at room temperature and 4-6 MPa for 10-20 min to obtain silicone rubber.

[0033] By adopting the above technical solution, a three-dimensional cross-linked thermal conductive network is formed in the silicone rubber by modifying the graphene-based filler, which can effectively improve the thermal conductivity and insulation properties of the silicone rubber. The above preparation method is simple and easy to operate and can be suitable for large-scale industrial production.

[0034] In a third aspect, the present application provides an application of a thermally conductive insulating liquid silicone rubber in the preparation of a thermal interface material.

[0035] By adopting the above technical solution, the thermally conductive insulating liquid silicone rubber provided by the present application has good mechanical properties and aging resistance, as well as good insulation and thermal conductivity, and can meet the heat dissipation and application requirements of high-power electronic devices.

[0036] 1. Since the present application adopts modified graphene-based fillers, hexagonal boron nitride and modified graphene-based fillers can form a three-dimensional cross-linked thermal conductive network in silicone rubber, thereby improving the thermal conductivity of silicone rubber. After loading zinc oxide particles, the modified graphene-based fillers can increase the number of thermal conductive pathways in silicone rubber, thereby effectively improving the thermal conductivity of silicone rubber. By adding liquid crystal polymers, the coverage area and extension path of the thermal conductive network in silicone rubber can be further improved by the liquid crystal polymers, thereby greatly enhancing the thermal conductivity of silicone rubber. In addition, liquid crystal polymers have good insulating properties. Liquid crystal polymers can enter the interlayer structure of graphene, thereby reducing the conductivity of graphene. Embedding liquid crystal polymers in the thermal conductive network can effectively enhance the insulation of the thermal conductive network, thereby improving the insulating properties of silicone rubber.

[0037] 2. In the present application, reduced graphene oxide filler is preferably used as the modified carrier. Reduced graphene oxide contains a large number of oxygen-containing functional groups, thus giving reduced graphene oxide good dispersibility and reactivity, which is beneficial for the uniform dispersion of reduced graphene oxide in the silicone rubber, and further beneficial for the formation of a three-dimensional cross-linked thermal conductive network with a uniform and stable structure inside the silicone rubber, thereby helping to improve the thermal conductivity of the silicone rubber.

[0038] 3. The preparation method of the present application forms a three-dimensional cross-linked thermal conductive network in silicone rubber by modifying the graphene-based filler, which can effectively improve the thermal conductivity and insulation properties of silicone rubber. The preparation method of the present application is simple and easy to operate, and can be applied to large-scale industrial production. DETAILED DESCRIPTION

[0039] The present application is further described in detail below in conjunction with embodiments.

[0040] The reduced graphene oxide powder, β-alanine solution, zinc acetate solution, glycerol ethyl ether and ethylenediamine reagent in the examples of the present application are all commercially available;

[0041] The average particle size of the hexagonal boron nitride and liquid crystal polymer in the present embodiment is 25 microns, and the specific surface area is 0.24 m 2 / g; the vulcanizing agent is double 25.

[0042] Preparation example of modified graphene-based filler

[0043] Preparation Example 1

[0044] S1: Dissolve 1 kg of 37% zinc acetate solution in 1.5 kg of glycerol ether, centrifuge and stir for 20 min, then add 0.305 mol of ethylenediamine, and stir at a constant temperature of 70°C for 0.5 h to obtain a zinc oxide colloidal solution;

[0045] S2: 2 kg of reduced graphene oxide powder was mixed with 2 kg of zinc oxide colloidal solution, the temperature was raised to 60° C., and then stirred at a constant temperature for 1 h to obtain a mixed solution;

[0046] S3: Add 1.2 kg of 20% mass concentration β-alanine solution to the mixed solution, then heat to 60° C., and then stir at constant temperature for 2 hours. After filtering, take the filter residue and calcine it at 250° C. to obtain a modified graphene-based filler.

[0047] Preparation Example 2

[0048] S1: Dissolve 1 kg of 37% zinc acetate solution in 1.5 kg of glycerol ether, centrifuge and stir for 25 min, then add 0.305 mol of ethylenediamine, and stir at a constant temperature of 75°C for 0.7 h to obtain a zinc oxide colloidal solution;

[0049] S2: 2 kg of reduced graphene oxide powder was mixed with 2.5 kg of zinc oxide colloidal solution, the temperature was raised to 65° C., and then stirred at a constant temperature for 1.2 h to obtain a mixed solution;

[0050] S3: Add 1.8 kg of β-alanine solution with a mass concentration of 22% to the mixed solution, then heat it to 65° C., and then stir it at a constant temperature for 2.5 hours. After filtering, take the filter residue and calcine it at 250° C. to obtain a modified graphene-based filler.

[0051] Preparation Example 3

[0052] S1: Dissolve 1 kg of 37% zinc acetate solution in 1.5 kg of glycerol ether, centrifuge and stir for 30 min, then add 0.305 mol of ethylenediamine, and stir at a constant temperature of 80°C for 1 h to obtain a zinc oxide colloidal solution;

[0053] S2: 2 kg of reduced graphene oxide powder was mixed with 3 kg of zinc oxide colloidal solution, the temperature was raised to 60° C., and then stirred at a constant temperature for 1 h to obtain a mixed solution;

[0054] S3: Add 2.5 kg of β-alanine solution with a mass concentration of 25% to the mixed solution, then heat it to 70° C., and then stir it at a constant temperature for 3 hours. After filtering, take the filter residue and calcine it at 250° C. to obtain a modified graphene-based filler.

[0055] Preparation Example 4

[0056] S1: Dissolve 1 kg of 37% zinc acetate solution in 1.5 kg of glycerol ether, centrifuge and stir for 30 min, then add 0.305 mol of ethylenediamine, and stir at a constant temperature of 80°C for 1 h to obtain a zinc oxide colloidal solution;

[0057] S2: 2 kg of reduced graphene oxide powder was mixed with 3 kg of zinc oxide colloidal solution, the temperature was raised to 60° C., and then stirred at a constant temperature for 1 h to obtain a mixed solution;

[0058] S3: The mixed solution was heated to 70° C., and then stirred at a constant temperature for 3 hours. After filtering, the filter residue was calcined at 250° C. to obtain a modified graphene-based filler.

[0059] Example

[0060] Example 1

[0061] A thermally conductive insulating liquid silicone rubber, the raw material components and their corresponding weights are shown in Table 1, and the preparation steps are as follows:

[0062] Step 1: Mixing: Mix dimethyl vinyl silicone rubber, hydroxyl-terminated silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler, vulcanizer and titanate coupling agent according to the ratio and mix them on a mixer. After mixing evenly, place them at room temperature for 6 hours to obtain a mixed rubber;

[0063] Step 2: Vulcanization: The mixed rubber obtained in step 1 was vulcanized at 170° C. and 6 MPa for 10 min, and then cooled at room temperature and 4 MPa for 10 min to obtain silicone rubber.

[0064] The modified graphene-based filler is the modified graphene-based filler prepared in Preparation Example 1.

[0065] Example 2

[0066] A thermally conductive insulating liquid silicone rubber, the raw material components and their corresponding weights are shown in Table 1, and the preparation steps are as follows:

[0067] Step 1: Mixing: Dimethyl vinyl silicone rubber, hydroxyl-terminated silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler, vulcanizing agent and titanate coupling agent are mixed according to a ratio and then mixed on a mixer. After mixing evenly, the mixture is placed at room temperature for 7 hours to obtain a mixed rubber;

[0068] Step 2: Vulcanization: The mixed rubber obtained in step 1 is vulcanized at 175° C. and 7 MPa for 15 min, and then cooled at room temperature and 5 MPa for 15 min to obtain silicone rubber.

[0069] The modified graphene-based filler is the modified graphene-based filler prepared in Preparation Example 2.

[0070] Example 3

[0071] A thermally conductive insulating liquid silicone rubber, the raw material components and their corresponding weights are shown in Table 1, and the preparation steps are as follows:

[0072] Step 1: Mixing: Dimethyl vinyl silicone rubber, hydroxyl-terminated silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler, vulcanizing agent and titanate coupling agent are mixed according to a ratio and mixed on a mixer. After mixing evenly, the mixture is placed at room temperature for 8 hours to obtain a mixed rubber;

[0073] Step 2: Vulcanization: The mixed rubber obtained in step 1 is vulcanized at 180° C. and 8 MPa for 20 min, and then cooled at room temperature and 6 MPa for 20 min to obtain silicone rubber.

[0074] The modified graphene-based filler is the modified graphene-based filler prepared in Preparation Example 3.

[0075] Table 1 Weight of each raw material in Examples 1-3 (kg)

[0076] Raw material name Example 1 Example 2 Example 3 Dimethyl vinyl silicone rubber 10 10 10 Hydroxyl-terminated silicone oil 0.8 1.2 1.5 Liquid Crystal Polymer 1.0 1.5 2.0 Hexagonal Boron Nitride 1.0 1.2 1.5 Modified graphene-based fillers 7.0 6.0 5.0 Vulcanizing agent 1.0 2.0 3.0 Titanate coupling agent 0.5 0.6 0.7

[0077] Example 4

[0078] A thermally conductive insulating liquid silicone rubber, which differs from Example 3 in that the modified graphene-based filler is the modified graphene-based filler prepared in Preparation Example 4.

[0079] Comparative Example

[0080] Comparative Example 1

[0081] A JC-819 thermally conductive insulating liquid silicone rubber purchased from a new material company in Guangdong.

[0082] Comparative Example 2

[0083] A thermally conductive insulating liquid silicone rubber, which differs from Example 3 in that an equal amount of reduced oxide graphene powder is used in the raw materials to replace the modified graphene-based filler.

[0084] Comparative Example 3

[0085] A thermally conductive insulating liquid silicone rubber, which differs from Example 3 in that an equal amount of the modified graphene-based filler prepared in Preparation Example 3 is used as the raw material to replace the liquid crystal high molecular polymer.

[0086] Comparative Example 4

[0087] A thermally conductive insulating liquid silicone rubber, which is different from Example 3 in that: the raw materials contain 0.9 kg of modified graphene-based filler and 0.5 kg of liquid crystal high molecular polymer.

[0088] Performance testing

[0089] The thermally conductive insulating liquid silicone rubbers obtained in Examples 1-4 and Comparative Examples 1-4 were injection molded, cured, and subjected to performance testing. The specific testing method is as follows:

[0090] Thermal conductivity: Tested according to ASTM-D5470.

[0091] Volume resistivity: Tested according to GB / T1410.

[0092] The specific test results are shown in Table 2:

[0093] Table 2 Performance test results

[0094] project Thermal conductivity / W / (m·K) Volume resistivity / Ω·cm Example 1 3.24 <![CDATA[6.25×10 12 ]]> Example 2 3.23 <![CDATA[6.22×10 12 ]]> Example 3 3.25 <![CDATA[6.28×10 12 ]]> Example 4 2.85 <![CDATA[4.32×10 12 ]]> Comparative Example 1 0.17 <![CDATA[1.02×10 11 ]]> Comparative Example 2 2.55 <![CDATA[1.25×10 11 ]]> Comparative Example 3 3.20 <![CDATA[1.20×10 11 ]]> Comparative Example 4 3.33 <![CDATA[2.24×10 12 ]]>

[0095] Combining Examples 1-3, Comparative Example 1 and Table 2, it can be seen that the thermal conductivity of the thermally conductive insulating liquid silicone rubber prepared in Examples 1-3 of the present application is stable at 3.24 W / (m·K), and the volume resistivity is about 6.25×10 12 Ω·cm, while the thermal conductivity of the JC-819 thermally conductive insulating liquid silicone rubber in Comparative Example 1 is 0.17W / (m·K) and the volume resistivity is 1.02×10 11It is obvious that the thermally conductive and insulating liquid silicone rubber prepared in the present application has better thermal conductive and insulating properties.

[0096] Combining Example 3, Comparative Example 2 and Table 2, it can be seen that the thermal conductivity and insulation of the thermally conductive insulating liquid silicone rubber of Comparative Example 2 are much worse than those of the thermally conductive insulating liquid silicone rubber of Example 3. Since Comparative Example 2 uses unmodified reduced graphene oxide powder, although the thermal conductivity of the thermally conductive insulating liquid silicone rubber is improved to a certain extent, the number of thermal conductive pathways in the silicone rubber is small, so the thermal conductivity is not as good as that of Example 3, and the unmodified reduced graphene oxide powder has good conductivity, which leads to the poor insulation of the thermally conductive insulating liquid silicone rubber of Comparative Example 2.

[0097] Combining Example 3, Comparative Example 3 and Table 2, it can be seen that since liquid crystal polymer is not used in the raw materials of Comparative Example 3, although the thermal conductivity of the silicone rubber is slightly different from that of Example 3, the volume resistivity of Comparative Example 3 is much smaller than that of Example 3. Since liquid crystal polymer is not used, the thermal conductive network in the silicone rubber has better thermal conductivity and better electrical conductivity, resulting in poor insulation of the silicone rubber in Comparative Example 3.

[0098] Combining Example 3, Comparative Example 4 and Table 2, it can be seen that the thermal conductivity of the silicone rubber of Comparative Example 4 is better than that of Example 3, but the insulation performance is worse than that of Example 3. The silicone rubber raw material that is better than Comparative Example 4 uses more modified graphene-based fillers, while the amount of liquid crystal polymer is reduced, resulting in an inappropriate ratio of the silicone rubber. The liquid crystal polymer cannot be evenly embedded in the interlayer structure of the graphene, which leads to a decrease in the insulation performance of the silicone rubber.

[0099] Combining Example 3, Example 4 and Table 2, it can be seen that the thermal conductivity and insulation properties of the silicone rubber prepared in Example 3 are better than those in Example 4. Since the silicone rubber of Example 4 uses the modified graphene-based filler prepared in Preparation Example 4, and the modified graphene-based filler is prepared in Preparation Example 4 without adding β-alanine solution, the stability of the zinc oxide particles in the reduced graphene oxide load is poor, and the zinc oxide particles are very easy to fall off and become free, thereby destroying the continuity of the thermal conductive network, resulting in poor thermal conductivity of the silicone rubber. After the zinc oxide particles fall off, the conductivity of the reduced graphene oxide is improved, thereby reducing the insulation properties of the silicone rubber.

[0100] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A thermally conductive insulating liquid silicone rubber, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of dimethyl vinyl silicone rubber; 8-15 parts of hydroxyl-terminated silicone oil; 10-20 parts of liquid crystal polymer; 10-15 parts of hexagonal boron nitride; 50-70 parts of modified graphene-based filler; 1-3 parts of vulcanizing agent; 5-7 parts of titanate coupling agent; The modified graphene-based filler is obtained by loading zinc oxide particles on the graphene-based filler; The graphene-based filler is a reduced graphene oxide filler, and the modified graphene-based filler is prepared by a method comprising the following steps: S1: Mix the reduced graphene oxide powder and the zinc oxide colloidal solution, raise the temperature to 60-70° C., and then stir at a constant temperature for 1-1.5 hours to obtain a mixed solution; S2: adding a β-alanine solution with a mass concentration of 20-25% to the mixed solution, then heating to 60-70° C., stirring at a constant temperature for 2-3 hours, filtering and calcining to obtain a modified graphene-based filler; The mass ratio of reduced graphene oxide powder to zinc oxide colloidal solution in S1 is 1:(1-1.5); the mass ratio of the mixed solution to β-alanine solution in S2 is 1:(0.3-0.5); The zinc oxide colloidal solution is prepared by the following method: dissolving zinc acetate solution in glycerol ether, stirring for 20-30 minutes, then adding ethylenediamine in an amount equal to the molar number of the zinc acetate solution, and stirring at a constant temperature of 70-80° C. for 0.5-1 hour to obtain the zinc oxide colloidal solution; The molecular weight of the hydroxyl-terminated silicone oil is 15,000-20,000, and the hydroxyl content is 0.17-0.23%; Thermally conductive insulating liquid silicone rubber is prepared by the following preparation method: Step 1: Mixing: Mix dimethyl vinyl silicone rubber, hydroxyl-terminated silicone oil, liquid crystal polymer, hexagonal boron nitride, modified graphene-based filler, vulcanizer and titanate coupling agent according to the ratio and mix them on a mixer. After mixing evenly, place them at room temperature for 6-8 hours to obtain a mixed rubber; Step 2: Vulcanization: The mixed rubber obtained in step 1 is vulcanized at 170-180° C. and 6-8 MPa for 10-20 min, and then cooled at room temperature and 4-6 MPa for 10-20 min to obtain silicone rubber.

2. Use of the thermally conductive insulating liquid silicone rubber according to claim 1 in the preparation of thermal interface materials.