Two-component silicone heat-conducting gel and preparation method thereof

Abstract

The application specifically relates to a two-component silicone heat-conducting gel and a preparation method thereof, wherein the heat-conducting gel comprises component A and component B, the weight ratio of the component A and the component B is 1:0.8-1.5; the component A comprises the following raw materials in parts by weight: 90-110 parts of vinyl silicone oil A, 80-120 parts of heat-conducting filler, 5-10 parts of tackifier, 2-6 parts of fumed silica, 0.1-1 part of inhibitor and 0.01-0.1 part of platinum catalyst; the component B comprises the following raw materials in parts by weight: 50-60 parts of vinyl silicone oil B, 10-20 parts of hydrogen-containing silicone oil, 80-120 parts of heat-conducting filler and 5-10 parts of cage polysilsesquioxane. The silicone heat-conducting gel has the advantages of heat conduction and bonding performance, low specific gravity and convenient automatic dispensing operation. The preparation method of the heat-conducting gel is stable in process, high in production efficiency and convenient in operation control, and is beneficial to industrial production.

Description

Technical Field

[0001] This invention relates to the field of thermal conductive gel technology, specifically to a two-component organosilicon thermal conductive gel and its preparation method. Background Technology

[0002] With societal progress and technological advancements, electronic products are evolving towards lighter weight, higher integration, and greater power, placing higher demands on the heat dissipation capabilities of materials. However, during operation, the heat generated by the internal electronic components of electronic devices increases rapidly. If this heat cannot be dissipated effectively and promptly, the performance and durability of these components will be significantly affected. Therefore, achieving efficient heat dissipation technology has become an important research direction in the field of electronic equipment.

[0003] In existing technologies, thermally conductive gels, as an important thermal interface material, have been widely used. Thermally conductive gels can be used to bond different components, providing fixation and cushioning, and can fill the tiny gaps between electronic components such as chips and heat dissipation devices, effectively reducing thermal resistance and improving heat transfer efficiency. Currently, silicone thermally conductive gels are widely used in the field of electronic packaging due to their excellent high and low temperature resistance, electrical insulation properties, and chemical stability.

[0004] However, current silicone thermal conductive gels on the market still have many problems and cannot fully meet the growing technological demands. For example, some thermal conductive gels add a large amount of thermally conductive fillers to improve thermal conductivity. This not only significantly increases the specific gravity of the material, failing to meet the requirements of fields such as new energy vehicles that have strict requirements for lightweighting, but also increases the viscosity of the material, causing great difficulties in automated dispensing operations during production and processing, reducing production efficiency and increasing production costs. Moreover, existing thermal conductive gels often struggle to balance thermal conductivity, adhesion, and lightweight properties. For example, some thermal conductive gels have good thermal conductivity but unsatisfactory adhesion properties and a high specific gravity, making them prone to displacement and detachment during use. On the other hand, some thermal conductive gels have good adhesion properties but poor thermal conductivity and unsatisfactory aging resistance. Therefore, developing a thermal conductive gel that combines good thermal conductivity and adhesion properties with a low specific gravity is of great significance. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a two-component silicone thermally conductive gel and its preparation method. The thermally conductive gel possesses both good thermal conductivity and adhesion properties, and has a low specific gravity, facilitating automated dispensing. The preparation method of the two-component silicone thermally conductive gel is stable, has high production efficiency, and is easy to operate and control, thus benefiting industrial production.

[0006] The objective of this invention is achieved through the following technical solution: a two-component organosilicon thermally conductive gel, comprising component A and component B, wherein the weight ratio of component A to component B is 1:0.8-1.5; component A comprises the following raw materials in parts by weight: vinyl silicone oil A 90-110 parts, thermally conductive filler 80-120 parts, tackifier 5-10 parts, fumed silica 2-6 parts, inhibitor 0.1-1 parts, platinum catalyst 0.01-0.1 parts; component B comprises the following raw materials in parts by weight: vinyl silicone oil B 50-60 parts, hydrogen-containing silicone oil 10-20 parts, thermally conductive filler 80-120 parts, cage-type polysilsesquioxane 5-10 parts.

[0007] Furthermore, the vinyl silicone oil A is a vinyl-terminated polydimethylsiloxane, referred to as the first vinyl-terminated polydimethylsiloxane, which has a viscosity of 200-1000 mPa·s and a vinyl content of 0.3-1.3%.

[0008] Furthermore, the vinyl silicone oil B is composed of vinyl-terminated polydimethylsiloxane and end-side vinyl silicone oil in a weight ratio of 3-4:1-2; the vinyl-terminated polydimethylsiloxane is referred to as the second vinyl-terminated polydimethylsiloxane.

[0009] Furthermore, the second vinyl-terminated polydimethylsiloxane has a viscosity of 2000-10000 mPa·s and a vinyl content of 0.1-0.3%. The end-side vinyl silicone oil has a viscosity of 100-500 mPa·s and a vinyl content of 0.6-1.5%.

[0010] Furthermore, the cage-like polysilsesquioxane is at least one of octavinyl cage-like polysilsesquioxane, octamethyl cage-like polysilsesquioxane, and octaepoxycyclohexylethyl cage-like polysilsesquioxane.

[0011] This invention utilizes a combination of first vinyl-terminated polydimethylsiloxane, second vinyl-terminated polydimethylsiloxane, and end-side vinyl silicone oil of different viscosities to balance rheological properties and crosslinking density, resulting in suitable curing hardness, good adhesion and strength, and facilitating automated dispensing. The cage-like polysilsesquioxane can synergistically work with the first vinyl-terminated polydimethylsiloxane, second vinyl-terminated polydimethylsiloxane, end-side vinyl silicone oil, and hydrogen-containing silicone oil to help improve the aging resistance and shear strength of the thermally conductive gel.

[0012] Furthermore, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and continuously stirring to carry out the reaction, and then centrifuging and drying to obtain the modified thermally conductive filler.

[0013] Furthermore, in the preparation method of the modified thermally conductive filler, the reaction temperature is 65-75℃, the reaction time is 60-120min, and the stirring speed is 1000-1500r / min.

[0014] Furthermore, in the preparation method of the modified thermally conductive filler, the weight ratio of the initial thermally conductive filler, coupling agent, stearic acid and ethanol is 40-60:1-4:1-4:80-120.

[0015] Furthermore, the initial thermally conductive filler is at least one of spherical alumina, aluminum nitride, and hollow glass microspheres.

[0016] Furthermore, the initial thermally conductive filler comprises the following raw materials in parts by weight: 40-60 parts of spherical alumina, 25-35 parts of aluminum nitride, and 15-25 parts of hollow glass microspheres.

[0017] Furthermore, the spherical alumina comprises 25-35 parts of micron-sized alumina and 15-25 parts of nano-sized alumina, wherein the particle size D50 of the micron-sized alumina is 5-10 μm, and the particle size of the nano-sized alumina is 100-150 nm. This invention, by combining micron-sized and nano-sized alumina, helps to fill the voids in the thermally conductive gel and improves the continuity of the thermal conduction path.

[0018] Furthermore, the aluminum nitride has a particle size D50 of 0.5-2 μm.

[0019] Furthermore, the hollow glass microspheres have a particle size D50 of 20-40 μm and a true density of 0.30-0.50 g / cm³. 3 .

[0020] This invention uses spherical alumina, aluminum nitride, and hollow glass microspheres as initial thermally conductive fillers, and modifies the thermally conductive fillers to form modified composite thermally conductive fillers. This effectively improves the compatibility and dispersibility of the thermally conductive fillers with the organosilicon matrix, helps to reduce interface defects, improves the thermal conductivity of the thermally conductive gel at low density, and also takes into account the adhesion performance.

[0021] Furthermore, the tackifier is at least one selected from γ-glycidoxypropyltrimethoxysilane, methacryloxypropyltrimethoxysilane, and MQ resin.

[0022] Furthermore, the inhibitor is at least one selected from 1-ethynyl-1-cyclohexanol, 3-methyl-1-butyn-3-ol, and diallyl maleate.

[0023] Furthermore, the platinum catalyst contains 2000-6000 ppm of platinum.

[0024] Furthermore, the hydrogen-containing silicone oil has a hydrogen mass fraction of 0.1-0.3% and a viscosity of 50-200 mPa·s.

[0025] This invention also provides a method for preparing a two-component organosilicon thermally conductive gel, comprising the following steps:

[0026] Preparation of component A:

[0027] The formulated amount of vinyl silicone oil A was added to a high-speed stirring vessel and stirred to fully disperse it; then, thermally conductive filler, fumed silica, thickener and inhibitor were added according to the ratio, and stirring was continued to ensure that the raw materials were mixed evenly; then, platinum catalyst was added and stirring was continued to obtain component A;

[0028] Preparation of component B:

[0029] Add the prescribed amount of vinyl silicone oil B to a high-speed mixing vessel and stir to fully disperse it; then add hydrogen-containing silicone oil and continue stirring to ensure that all raw materials are mixed evenly; finally, add the prescribed amount of cage-type polysilsesquioxane and thermally conductive filler.

[0030] Continue stirring to obtain component B;

[0031] Packaging and mixing:

[0032] The prepared components A and B are placed into separate packaging containers and sealed for storage; when ready for use, components A and B are mixed evenly in proportion.

[0033] This invention prepares component A and component B separately through raw material compounding and process optimization, ensuring uniform dispersion and good compounding of each raw material. Component A and component B are packaged separately. When using, components A and B can be mixed in proportion. The preparation method of the two-component organosilicon thermal conductive gel has the advantages of stable process, high production efficiency, and easy operation and control.

[0034] The beneficial effects of this invention are as follows: The two-component silicone thermally conductive gel of this invention is prepared by compounding raw materials such as vinyl silicone oil, thermally conductive filler, tackifier, fumed silica, inhibitor, and platinum catalyst to obtain component A, and compounding raw materials such as vinyl silicone oil, hydrogen-containing silicone oil, thermally conductive filler, and cage-type polysilsesquioxane to obtain component B. Component A and component B are mixed and then cured before use. The two-component silicone thermally conductive gel combines thermal conductivity and adhesion properties, and has a low specific gravity, facilitating automated dispensing. The preparation method of the two-component silicone thermally conductive gel is stable, has high production efficiency, and is easy to operate and control, which is beneficial for industrial production. Detailed Implementation

[0035] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0036] In some embodiments of the present invention, a two-component organosilicon thermal conductive gel includes component A and component B, wherein the weight ratio of component A to component B is 1:0.8-1.5.

[0037] Component A comprises the following raw materials in parts by weight: 90-110 parts vinyl silicone oil A, 80-120 parts thermally conductive filler, 5-10 parts tackifier, 2-6 parts fumed silica, 0.1-1 parts inhibitor, and 0.01-0.1 parts platinum catalyst;

[0038] Component B comprises the following raw materials in parts by weight: 50-60 parts of vinyl silicone oil B, 10-20 parts of hydrogen-containing silicone oil, 80-120 parts of thermally conductive filler, and 5-10 parts of cage-type polysilsesquioxane.

[0039] In some embodiments of the present invention, the vinyl silicone oil A is a first vinyl-terminated polydimethylsiloxane, the first vinyl-terminated polydimethylsiloxane having a viscosity of 200-1000 mPa·s (25°C) and a vinyl content of 0.3-1.3%.

[0040] In some embodiments of the present invention, the vinyl silicone oil B is composed of a second vinyl-terminated polydimethylsiloxane and an end-side vinyl silicone oil in a weight ratio of 3-4:1-2.

[0041] In some embodiments of the present invention, the viscosity of the second vinyl-terminated polydimethylsiloxane is 2000-10000 mPa·s (25°C), and the vinyl content is 0.1-0.3%. The viscosity of the end-side vinyl silicone oil is 100-500 mPa·s (25°C), and the vinyl content is 0.6-1.5%.

[0042] The two-component silicone thermal conductive gel of this invention is prepared by mixing components A and B, and can be cured by baking at 100°C for 15 minutes or longer while maintaining good adhesive strength. This two-component silicone thermal conductive gel combines good thermal conductivity, adhesion, and aging resistance, and has a low specific gravity, which helps reduce equipment weight, facilitates automated dispensing operations, and improves dispensing efficiency; for example, a pneumatic dispensing machine can be used. The thermal conductive gel can be used in scenarios such as heat sink and chip fixing and heat dissipation, reducing the steps of installing screws or clips; it can also be used in scenarios such as heat dissipation, cushioning, and fixing of battery packs, exhibiting a wide range of applications and promising market prospects.

[0043] In some embodiments of the present invention, the cage-like polysilsesquioxane is at least one of octavinyl cage-like polysilsesquioxane, octamethyl cage-like polysilsesquioxane, and octaepoxycyclohexylethyl cage-like polysilsesquioxane.

[0044] In some embodiments of the present invention, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and continuously stirring to carry out the reaction, the reaction temperature is 65-75℃, the reaction time is 60-120min, and the stirring speed is 1000-1500r / min; then centrifuging and drying are performed to obtain the modified thermally conductive filler.

[0045] In some embodiments of the present invention, in the preparation method of the modified thermally conductive filler, the weight ratio of the initial thermally conductive filler, coupling agent, stearic acid and ethanol is 40-60:1-4:1-4:80-120.

[0046] In some embodiments of the present invention, in the preparation method of the modified thermally conductive filler, the coupling agent is at least one selected from γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, dodecyltrimethoxysilane, and hexadecyltriethoxysilane.

[0047] In some embodiments of the present invention, the initial thermally conductive filler is at least one of spherical alumina, aluminum nitride, and hollow glass microspheres.

[0048] In some embodiments of the present invention, the initial thermally conductive filler comprises the following raw materials in parts by weight: 40-60 parts of spherical alumina, 25-35 parts of aluminum nitride, and 15-25 parts of hollow glass microspheres.

[0049] In some embodiments of the present invention, the spherical alumina comprises 25-35 parts of micron-sized alumina and 15-25 parts of nano-sized alumina, wherein the particle size D50 of the micron-sized alumina is 5-10 μm and the particle size of the nano-sized alumina is 100-150 nm.

[0050] In some embodiments of the present invention, the aluminum nitride has a particle size D50 of 0.5-2 μm.

[0051] In some embodiments of the present invention, the hollow glass microspheres have a particle size D50 of 20-40 μm and a true density of 0.30-0.50 g / cm³. 3 .

[0052] In some embodiments of the present invention, the tackifier is at least one selected from γ-glycidoxypropyltrimethoxysilane, methacryloyloxypropyltrimethoxysilane, and MQ resin.

[0053] In some embodiments of the present invention, the fumed silica is hydrophobic. The fumed silica exhibits good compatibility with the organosilicon matrix and possesses excellent thickening thixotropic efficiency, which helps improve the process applicability and overall product performance of the thermally conductive gel.

[0054] In some embodiments of the present invention, the inhibitor is at least one selected from 1-ethynyl-1-cyclohexanol, 3-methyl-1-butyn-3-ol, and diallyl maleate.

[0055] In some embodiments of the present invention, the platinum catalyst contains 2000-6000 ppm of platinum. The platinum catalyst is preferably, but not limited to, a Karstedt catalyst.

[0056] In some embodiments of the present invention, the hydrogen-containing silicone oil has a hydrogen mass fraction of 0.1-0.3% and a viscosity of 50-200 mPa·s (25°C).

[0057] In some embodiments of the present invention, a method for preparing a two-component organosilicon thermally conductive gel includes the following steps:

[0058] Preparation of component A:

[0059] Add the prescribed amount of vinyl silicone oil A to a high-speed stirred tank and stir at 300-500 r / min for 10-20 min to fully disperse it; then add thermally conductive filler, fumed silica, thickener, and inhibitor according to the formula, and continue stirring for 30-60 min to ensure that the raw materials are mixed evenly; then add platinum catalyst, and stir for 10-20 min under a vacuum of -0.07 to -0.09 MPa to obtain component A.

[0060] Preparation of component B:

[0061] Add the prescribed amount of vinyl silicone oil B to a high-speed stirred tank and stir at 300-500 r / min for 10-20 min to fully disperse it; then add hydrogen-containing silicone oil and stir for 15-30 min to ensure that all raw materials are mixed evenly; then add the prescribed amount of cage-type polysilsesquioxane and thermally conductive filler, and stir under a vacuum of -0.07 to -0.09 MPa for 20-40 min to obtain component B;

[0062] Packaging and mixing:

[0063] The prepared components A and B are placed into separate packaging containers and sealed for storage; when ready for use, components A and B are mixed evenly in proportion.

[0064] In the following embodiments of the present invention, the first vinyl-terminated polydimethylsiloxane is vinyl silicone oil NV500 from Zhejiang Chuanhe Chemical Co., Ltd. The second vinyl-terminated polydimethylsiloxane is vinyl silicone oil NV5000 from Zhejiang Chuanhe Chemical Co., Ltd. The end-side vinyl silicone oil is JP-02V-300 from Shenzhen Jipeng Silicon Fluorine Materials Co., Ltd. The hydrogen-containing silicone oil is purchased from Shanghai Siyou New Materials Technology Co., Ltd., with a viscosity of 100-200 mPa·s. The MQ resin is vinyl MQ silicone resin 5202S purchased from Jining Tangyi Chemical Co., Ltd. The octamethyl cage-type polysilsesquioxane is purchased from Xi'an Qiyue Biotechnology Co., Ltd. Fumed silica is Evonik Degussa R202 fumed silica.

[0065] Example 1

[0066] In this embodiment, a two-component silicone thermal conductive gel includes component A and component B, wherein the weight ratio of component A to component B is 1:1.

[0067] Component A comprises the following raw materials in parts by weight: 100 parts vinyl silicone oil A, 90 parts thermally conductive filler, 8 parts tackifier, 4 parts fumed silica, 0.4 parts inhibitor, and 0.03 parts platinum catalyst.

[0068] Component B comprises the following raw materials in parts by weight: 55 parts vinyl silicone oil B, 15 parts hydrogen-containing silicone oil, 90 parts thermally conductive filler, and 6 parts cage-type polysilsesquioxane.

[0069] Furthermore, the vinyl silicone oil A is a first vinyl-terminated polydimethylsiloxane. The vinyl silicone oil B is composed of a second vinyl-terminated polydimethylsiloxane and an end-side vinyl silicone oil in a weight ratio of 3.5:1.5. The cage-like polysilsesquioxane is an octamethyl cage-like polysilsesquioxane.

[0070] Furthermore, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and continuously stirring, reacting at 70°C for 90 min, and stirring at 1200 r / min; then centrifuging and vacuum drying to obtain the modified thermally conductive filler.

[0071] Furthermore, in the preparation method of the modified thermally conductive filler, the weight ratio of the initial thermally conductive filler, coupling agent, stearic acid, and ethanol is 50:3:2:110. The coupling agent is composed of γ-glycidoxypropyltrimethoxysilane and dodecyltrimethoxysilane in a weight ratio of 1:1.

[0072] Furthermore, the initial thermally conductive filler comprises the following raw materials in parts by weight: 50 parts spherical alumina, 30 parts aluminum nitride, and 20 parts hollow glass microspheres.

[0073] Furthermore, the spherical alumina comprises 30 parts of micron-sized alumina and 20 parts of nano-sized alumina, wherein the particle size D50 of the micron-sized alumina is 5-10 μm, and the particle size of the nano-sized alumina is 100-150 nm. The particle size D50 of the aluminum nitride is 0.5-2 μm.

[0074] Furthermore, the tackifier is composed of γ-glycidoxypropyltrimethoxysilane and MQ resin in a weight ratio of 1:1.

[0075] Furthermore, the inhibitor is composed of 1-ethynyl-1-cyclohexanol and diallyl maleate in a weight ratio of 2:1. The platinum catalyst contains 3000 ppm of platinum.

[0076] In this embodiment, a method for preparing a two-component organosilicon thermally conductive gel includes the following steps:

[0077] Preparation of component A:

[0078] Add the formulated amount of vinyl silicone oil A to a high-speed stirred tank and stir at 400 r / min for 15 min to fully disperse it; then add thermally conductive filler, thickener, fumed silica and inhibitor according to the ratio, and continue stirring for 30 min under a vacuum of -0.085 MPa to make the raw materials evenly mixed; then add platinum catalyst and stir for 10 min to obtain component A.

[0079] Preparation of component B:

[0080] Add the formulated amount of vinyl silicone oil B to a high-speed stirring vessel and stir at 400 r / min for 15 min; then add hydrogen-containing silicone oil and stir for 20 min to ensure that the raw materials are mixed evenly; then add the formulated amount of cage-type polysilsesquioxane and thermally conductive filler, and stir for 30 min under a vacuum of -0.09 MPa to obtain component B.

[0081] Packaging and mixing:

[0082] The prepared components A and B are placed into separate packaging containers and sealed for storage; when ready for use, components A and B are mixed evenly in proportion.

[0083] Example 2

[0084] In this embodiment, a two-component silicone thermal conductive gel includes component A and component B, wherein the weight ratio of component A to component B is 1:1.

[0085] Component A comprises the following raw materials in parts by weight: 100 parts vinyl silicone oil A, 90 parts thermally conductive filler, 8 parts tackifier, 4 parts fumed silica, 0.4 parts inhibitor, and 0.03 parts platinum catalyst.

[0086] Component B comprises the following raw materials in parts by weight: 55 parts vinyl silicone oil B, 15 parts hydrogen-containing silicone oil, 90 parts thermally conductive filler, and 5 parts cage-type polysilsesquioxane.

[0087] Furthermore, the vinyl silicone oil A is a first vinyl-terminated polydimethylsiloxane. The vinyl silicone oil B is composed of a second vinyl-terminated polydimethylsiloxane and an end-side vinyl silicone oil in a weight ratio of 4:1. The cage-like polysilsesquioxane is an octamethyl cage-like polysilsesquioxane.

[0088] Furthermore, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and continuously stirring, reacting at 70°C for 90 min, and stirring at 1200 r / min; then centrifuging and vacuum drying to obtain the modified thermally conductive filler.

[0089] Furthermore, in the preparation method of the modified thermally conductive filler, the weight ratio of the initial thermally conductive filler, coupling agent, stearic acid, and ethanol is 50:2:1.5:107. The coupling agent is composed of γ-aminopropyltrimethoxysilane and dodecyltrimethoxysilane in a weight ratio of 1:1.

[0090] Furthermore, the initial thermally conductive filler comprises the following raw materials in parts by weight: 45 parts spherical alumina, 35 parts aluminum nitride, and 20 parts hollow glass microspheres.

[0091] Furthermore, the spherical alumina comprises 30 parts of micron-sized alumina and 15 parts of nano-sized alumina, wherein the particle size D50 of the micron-sized alumina is 5-10 μm, and the particle size of the nano-sized alumina is 100-150 nm. The particle size D50 of the aluminum nitride is 0.5-2 μm.

[0092] Furthermore, the tackifier is composed of γ-glycidoxypropyltrimethoxysilane and MQ resin in a weight ratio of 1:1.

[0093] Furthermore, the inhibitor is composed of 1-ethynyl-1-cyclohexanol and diallyl maleate in a weight ratio of 2:1.

[0094] In this embodiment, a method for preparing a two-component organosilicon thermally conductive gel includes the following steps:

[0095] Preparation of component A:

[0096] Add the formulated amount of vinyl silicone oil A to a high-speed stirred tank and stir at 400 r / min for 15 min to fully disperse it; then add thermally conductive filler, thickener, fumed silica and inhibitor according to the ratio, and continue stirring for 30 min under a vacuum of -0.085 MPa to make the raw materials evenly mixed; then add platinum catalyst and stir for 15 min to obtain component A.

[0097] Preparation of component B:

[0098] Add the formulated amount of vinyl silicone oil B to a high-speed stirring vessel and stir at 400 r / min for 15 min; then add hydrogen-containing silicone oil and stir for 20 min to ensure that the raw materials are mixed evenly; then add the formulated amount of cage-type polysilsesquioxane and thermally conductive filler, and stir for 30 min under a vacuum of -0.08 MPa to obtain component B.

[0099] Packaging and mixing:

[0100] The prepared components A and B are placed into separate packaging containers and sealed for storage; when ready for use, components A and B are mixed evenly in proportion.

[0101] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0102] Example 3

[0103] In this embodiment, a two-component silicone thermal conductive gel includes component A and component B, wherein the weight ratio of component A to component B is 1:1.

[0104] Component A comprises the following raw materials in parts by weight: 110 parts vinyl silicone oil A, 120 parts thermally conductive filler, 10 parts tackifier, 6 parts fumed silica, 0.8 parts inhibitor, and 0.04 parts platinum catalyst.

[0105] Component B comprises the following raw materials in parts by weight: 60 parts vinyl silicone oil B, 18 parts hydrogen-containing silicone oil, 110 parts thermally conductive filler, and 5 parts cage-type polysilsesquioxane.

[0106] Furthermore, the vinyl silicone oil A is a first vinyl-terminated polydimethylsiloxane. The vinyl silicone oil B is composed of a second vinyl-terminated polydimethylsiloxane and an end-side vinyl silicone oil in a weight ratio of 4:1. The cage-like polysilsesquioxane is an octamethyl cage-like polysilsesquioxane.

[0107] Furthermore, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and continuously stirring, reacting at 70°C for 90 min, and stirring at 1200 r / min; then centrifuging and vacuum drying to obtain the modified thermally conductive filler.

[0108] Furthermore, the initial thermally conductive filler comprises the following raw materials in parts by weight: 55 parts spherical alumina, 30 parts aluminum nitride, and 15 parts hollow glass microspheres.

[0109] Furthermore, the spherical alumina comprises 25 parts micron-sized alumina and 20 parts nano-sized alumina, wherein the micron-sized alumina has a particle size D50 of 5-10 μm, and the nano-sized alumina has a particle size of 100-150 nm. The aluminum nitride has a particle size D50 of 0.5-2 μm.

[0110] Furthermore, the tackifier is composed of methacryloyloxypropyltrimethoxysilane and MQ resin in a weight ratio of 1:1.

[0111] Furthermore, the inhibitor is composed of 1-ethynyl-1-cyclohexanol and diallyl maleate in a weight ratio of 2:1. The platinum catalyst contains 2000 platinum particles.

[0112] In this embodiment, a method for preparing a two-component organosilicon thermally conductive gel includes the following steps:

[0113] Preparation of component A:

[0114] Add the formulated amount of vinyl silicone oil A to a high-speed stirred tank and stir at 400 r / min for 15 min to fully disperse it; then add thermally conductive filler, thickener, fumed silica and inhibitor according to the ratio, and continue stirring for 30 min under a vacuum of -0.085 MPa to make the raw materials evenly mixed; then add platinum catalyst and stir for 10 min to obtain component A.

[0115] Preparation of component B:

[0116] Add the formulated amount of vinyl silicone oil B to a high-speed stirring vessel and stir at 400 r / min for 15 min; then add hydrogen-containing silicone oil and stir for 20 min to ensure that the raw materials are mixed evenly; then add the formulated amount of cage-type polysilsesquioxane and thermally conductive filler, and stir for 30 min under a vacuum of -0.09 MPa to obtain component B.

[0117] Packaging and mixing:

[0118] The prepared components A and B are placed into separate packaging containers and sealed for storage; when ready for use, components A and B are mixed evenly in proportion.

[0119] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0120] Example 4

[0121] In this embodiment, a two-component silicone thermal conductive gel includes component A and component B, wherein the weight ratio of component A to component B is 1:1.2.

[0122] Component A comprises the following raw materials in parts by weight: 105 parts vinyl silicone oil A, 95 parts thermally conductive filler, 10 parts tackifier, 5 parts fumed silica, 0.5 parts inhibitor, and 0.04 parts platinum catalyst.

[0123] Component B comprises the following raw materials in parts by weight: 55 parts vinyl silicone oil B, 15 parts hydrogen-containing silicone oil, 100 parts thermally conductive filler, and 6 parts cage-type polysilsesquioxane.

[0124] Furthermore, the thermally conductive filler is a modified thermally conductive filler, and the preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and stirring continuously, reacting at 75°C for 80 min, and stirring at 1200 r / min; then centrifuging and vacuum drying to obtain the modified thermally conductive filler.

[0125] Furthermore, the initial thermally conductive filler comprises the following raw materials in parts by weight: 45 parts spherical alumina, 35 parts aluminum nitride, and 20 parts hollow glass microspheres. The spherical alumina includes 30 parts micron-sized alumina and 20 parts nano-sized alumina, wherein the micron-sized alumina has a particle size D50 of 5-10 μm, and the nano-sized alumina has a particle size of 100-150 nm. The aluminum nitride has a particle size D50 of 0.5-2 μm.

[0126] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0127] Comparative Example 1

[0128] The difference between this comparative example and Example 1 is that the thermally conductive filler used in the two-component silicone thermally conductive gel in this comparative example is an equal weight of unmodified initial thermally conductive filler.

[0129] Comparative Example 2

[0130] The difference between this comparative example and Example 1 is that component B in the two-component silicone thermal conductive gel in this comparative example does not contain cage-like polysilsesquioxane.

[0131] Comparative Example 3

[0132] The difference between this comparative example and Example 1 is that in the two-component silicone thermal conductive gel of this comparative example, the vinyl silicone oil B in component B is replaced by an equal weight of vinyl silicone oil A.

[0133] The two-component silicone thermal conductive gels prepared in Example 1 and Comparative Examples 1-3 were prepared and used immediately, cured at 100°C for 20 minutes, and then their performance was tested. The test results are shown in Table 1 below:

[0134]

[0135]

[0136] The extrusion rate test conditions were: 0.1-foot needle @ 75 PSI, equipment: EFD dispensing system, dispensing syringe capacity: 30 cm³. 3 The high-temperature aging resistance test involved aging the cured samples in a 150°C oven for 1000 hours, then cooling them to room temperature and calculating the rate of change from the initial shear strength, based on the tested shear strength. The double 85 test involved treating the cured samples at 85°C / 85% RH for 1000 hours, then placing them at 25°C / 50% RH for 4 hours, and calculating the rate of change from the initial shear strength. Referring to the UL 94 testing standard, the 1.6 mm samples from Examples 1-4 and Comparative Examples 1-3 were determined to meet the UL 94 V-0 rating.

[0137] The two-component silicone thermally conductive gel of this invention is prepared by compounding vinyl silicone oil, thermally conductive filler, tackifier, fumed silica, inhibitor, and platinum catalyst to obtain component A, and compounding vinyl silicone oil, hydrogen-containing silicone oil, thermally conductive filler, and cage-type polysilsesquioxane to obtain component B. Component A and component B are mixed for rapid curing upon heating, resulting in suitable curing hardness. This two-component silicone thermally conductive gel exhibits good thermal conductivity, adhesion, and heat aging resistance, and has a low specific gravity, facilitating automated dispensing. Its preparation method is stable, efficient, and easy to control, making it suitable for industrial production.

[0138] The specific embodiments described above are further illustrations of the technical solution and beneficial effects of the present invention, and are not intended to limit the implementation methods. For those skilled in the art, any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. A two-component silicone thermally conductive gel, comprising component A and component B, wherein the weight ratio of component A to component B is 1:0.8-1.5; component A comprises the following raw materials in parts by weight: 90-110 parts of vinyl silicone oil A, 80-120 parts of thermally conductive filler, 5-10 parts of tackifier, 2-6 parts of fumed silica, 0.1-1 parts of inhibitor, and 0.01-0.1 parts of platinum catalyst; component B comprises the following raw materials in parts by weight: 50-60 parts of vinyl silicone oil B, 10-20 parts of hydrogen-containing silicone oil, 80-120 parts of thermally conductive filler, and 5-10 parts of cage-type polysilsesquioxane; The vinyl silicone oil A is a vinyl-terminated polydimethylsiloxane with a viscosity of 200-1000 mPa·s and a vinyl content of 0.3-1.3%. The vinyl silicone oil B is composed of vinyl-terminated polydimethylsiloxane and end-side vinyl silicone oil in a weight ratio of 3-4:1-2. The vinyl-terminated polydimethylsiloxane has a viscosity of 2000-10000 mPa·s and a vinyl content of 0.1-0.3%. The end-side vinyl silicone oil has a viscosity of 100-500 mPa·s and a vinyl content of 0.6-1.5%. The thermally conductive filler is a modified thermally conductive filler. The preparation method of the modified thermally conductive filler includes the following steps: adding the initial thermally conductive filler, coupling agent and stearic acid into ethanol, mixing and stirring continuously to carry out the reaction, and then centrifuging and drying to obtain the modified thermally conductive filler. The initial thermally conductive filler comprises the following raw materials in parts by weight: 40-60 parts of spherical alumina, 25-35 parts of aluminum nitride, and 15-25 parts of hollow glass microspheres; the spherical alumina comprises 25-35 parts of micron-sized alumina and 15-25 parts of nano-sized alumina; the particle size D50 of the micron-sized alumina is 5-10 μm, the particle size D50 of the nano-sized alumina is 100-150 nm, and the particle size D50 of the hollow glass microspheres is 20-40 μm; The cage-type polysilsesquioxane is at least one of octavinyl cage-type polysilsesquioxane, octamethyl cage-type polysilsesquioxane, and octaepoxycyclohexylethyl cage-type polysilsesquioxane.

2. The two-component organosilicon thermally conductive gel according to claim 1, characterized in that: In the preparation method of the modified thermally conductive filler, the reaction temperature is 65-75℃, the reaction time is 60-120min, and the stirring speed is 1000-1500 r / min.

3. The two-component organosilicon thermally conductive gel according to claim 1, characterized in that: The tackifier is at least one of γ-glycidoxypropyltrimethoxysilane, methacryloyloxypropyltrimethoxysilane, and MQ resin.

4. The two-component organosilicon thermally conductive gel according to claim 1, characterized in that: The inhibitor is at least one of 1-ethynyl-1-cyclohexanol, 3-methyl-1-butyn-3-ol, and diallyl maleate.

5. A method for preparing a two-component organosilicon thermally conductive gel as described in any one of claims 1-4, characterized in that: Includes the following steps: Preparation of component A: The prescribed amount of vinyl silicone oil A was added to a high-speed stirred tank and stirred to ensure thorough dispersion. Then, thermally conductive filler, thickener, fumed silica, and inhibitor were added according to the specified ratio, and stirring was continued until all raw materials were uniformly mixed. Finally, a platinum catalyst was added, and stirring was continued to obtain component A. Preparation of component B: Add the formulated amount of vinyl silicone oil B to a high-speed mixing vessel and stir to fully disperse it; then add hydrogen-containing silicone oil and continue stirring to mix the raw materials evenly; then add the formulated amount of cage-type polysilsesquioxane and thermally conductive filler, and continue stirring to obtain component B; Packaging and mixing: The prepared components A and B are placed into separate packaging containers and sealed for storage. When ready to use, mix components A and B thoroughly in the specified proportions.

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