Two-component heat-conducting gel with low expansion coefficient and preparation method of two-component heat-conducting gel

Abstract

The invention discloses double-component heat-conducting gel with a low expansion coefficient and a preparation method of the double-component heat-conducting gel. A component A of the gel comprises 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.01-0.05 part of a coloring agent, 5-15 parts of a negative thermal expansion agent, 5-10 parts of small-particle-size aluminum oxide, 20-35 parts of medium-particle-size aluminum oxide, 40-60 parts of large-particle-size aluminum oxide and 0.01-0.05 part of a platinum catalyst; the component B comprises 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.3-1.5 parts of side hydrogen-containing silicone oil, 0.3-1.5 parts of end hydrogen-containing silicone oil, 5-15 parts of a negative thermal expansion agent, 5-10 parts of small-particle-size aluminum oxide, 20-35 parts of medium-particle-size aluminum oxide and 40-60 parts of large-particle-size aluminum oxide. According to the gel, the silicon resin, the hydrogen-containing silicone oil, the negative thermal expansion agent, the aluminum oxide and other components are reasonably matched, so that the heat-conducting gel with excellent mechanical properties and lower thermal expansion coefficient is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of thermal conductive materials, and in particular to a two-component thermal conductive gel with a low expansion coefficient and a preparation method thereof. Background Art

[0002] In the electronic equipment industry, two-component thermally conductive gel is widely used as part of the heat sink, especially on high-performance processors that are sensitive to temperature changes. It can effectively transfer heat from the chip surface to a larger heat sink or housing, thereby maintaining stable operation of the device.

[0003] Currently, the more commonly used two-component silicone thermally conductive gels generally pursue high thermal conductivity, low thermal resistance or high dispensing efficiency, and their thermal expansion coefficients are generally around 200ppm / ℃. In the field of mid-to-high-end electronic equipment, which pursues the trend of thinness, smallness and high precision, the influence of thermal expansion of two-component thermally conductive gels in addition to stable and efficient heat dissipation is becoming more and more prominent. The smaller the thermal expansion coefficient of the two-component thermally conductive gel, the smaller the degree of deformation at different temperatures, so it can better protect the stability of electronic components. In precision electronic equipment, the thermal expansion coefficient of the material must be strictly controlled to ensure that the size of the device remains stable when the temperature changes, to avoid deformation or functional failure of the device due to thermal expansion.

[0004] At present, there are related reports in China, such as CN114538888A discloses a polymer hydrogel with extremely low expansion rate in physiological environment, which has a low expansion coefficient, but it is mainly composed of a single component and is used in biological direction, not electronic equipment. For example, CN108777304A discloses a special gel for battery zinc paste, which is made of cationic polyacrylamide, homemade composite gel and modified sodium alginate, etc., which has a low expansion coefficient, but it is mainly composed of a single component, and its thermal conductivity is poor. In the two-component product, similar products have not yet appeared. Therefore, the development of such products is of great significance to the research and development of precision electronic equipment in my country. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, one of the objectives of the present invention is to provide a two-component thermally conductive gel with a low expansion coefficient to solve the above-mentioned traditional technical problems.

[0006] A second object of the present invention is to provide a method for preparing the above-mentioned two-component thermally conductive gel with a low expansion coefficient.

[0007] One of the purposes of the present invention is achieved by the following technical solution: A two-component thermally conductive gel with a low expansion coefficient, comprising a component A and a component B; The A component includes the following components in parts by weight: 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.01-0.05 parts of colorant, 5-15 parts of negative thermal expansion agent, 5-10 parts of small-particle alumina, 20-35 parts of medium-particle alumina, 40-60 parts of large-particle alumina, 0.01-0.05 parts of platinum catalyst; The B component includes the following components in parts by weight: 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.3-1.5 parts of side hydrogen-containing silicone oil, 0.3-1.5 parts of end hydrogen-containing silicone oil, 5-15 parts of negative thermal expansion agent, 5-10 parts of small particle size alumina, 20-35 parts of medium particle size alumina, 40-60 parts of large particle size alumina.

[0008] In the present invention, a two-component silicone thermally conductive gel with excellent mechanical properties and a low thermal expansion coefficient is obtained by rationally combining and using silicone resins such as vinyl silicone oil, MQ resin, side hydrogen-containing silicone oil, end hydrogen-containing silicone oil, negative thermal expansion agent, and aluminum oxide of different sizes.

[0009] In the present invention, the weight parts of the vinyl silicone oil can be 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, etc.

[0010] The weight proportions of MQ resin can be 0.5 parts, 0.8 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc.

[0011] The weight percentage of the colorant can be 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part, etc.

[0012] The weight proportions of the negative thermal expansion agent may be 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, etc.

[0013] The weight proportion of small particle size alumina can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0014] The weight proportions of medium particle size alumina can be 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts, etc.

[0015] The weight proportion of large particle size alumina can be 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, etc.

[0016] The weight proportion of the platinum catalyst can be 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part, etc.

[0017] The weight proportion of the side hydrogen-containing silicone oil can be 0.3 parts, 0.5 parts, 0.8 parts, 1 parts, 1.2 parts, 1.5 parts, etc.

[0018] The weight proportion of the terminal hydrogen-containing silicone oil can be 0.3 parts, 0.5 parts, 0.8 parts, 1 parts, 1.2 parts, 1.5 parts, etc.

[0019] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0020] Furthermore, the vinyl silicone oil is vinyl-terminated polydimethylsiloxane, and its viscosity at 25° C. is 300 Pa.s-1000 Pa.s, for example, it can be 300 Pa.s, 400 Pa.s, 500 Pa.s, 600 Pa.s, 700 Pa.s, 800 Pa.s, 900 Pa.s, 1000 Pa.s, etc.

[0021] Furthermore, the MQ resin is polyvinyl silicone oil, and the vinyl content thereof is 2wt%-6wt%, for example, 2wt%, 3wt%, 4wt%, 5wt%, 6wt% and the like.

[0022] Among the above, silicone resins such as polyvinyl silicone oil and terminal vinyl polydimethylsiloxane can provide branching and cross-linking points to form a cross-linking network, so that the gel has the ability to retain its shape, while hydrogen-containing silicone oils such as side hydrogen-containing silicone oil and terminal hydrogen-containing silicone oil can extend the chain, reduce the cross-linking density and reduce the modulus.

[0023] Furthermore, the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm-5000ppm, for example, it can be 1000ppm, 2000ppm, 3000ppm, 4000ppm, 5000ppm, etc.

[0024] Furthermore, the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%-0.5wt%, for example, it can be 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt% and the like.

[0025] Furthermore, the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%-0.1wt%, for example, it can be 0.05wt%, 0.07wt%, 0.09wt%, 0.1wt% and the like.

[0026] Furthermore, the colorant is an inorganic filler with a coloring effect, specifically at least one of carbon black, red iron oxide, and mica iron oxide gray.

[0027] Furthermore, the negative thermal expansion agent is at least one of zirconium tungstate and yttrium tungstate, and its average particle size is 0.4 μm-2 μm, for example, 0.4 μm, 0.8 μm, 1 μm, 1.5 μm, 2 μm, etc. The content and particle size of the negative thermal expansion agent are strictly controlled, and then combined with silicone resin, hydrogenated silicone oil and alumina to obtain a gel with a lower expansion coefficient.

[0028] Furthermore, the small-particle aluminum oxide is spherical aluminum oxide with an average particle size of 0.4 μm-1 μm, for example, 0.4 μm, 0.8 μm, 1 μm, etc.

[0029] Furthermore, the medium-sized alumina is spherical alumina with an average particle size of 5 μm-10 μm, for example, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm, etc.

[0030] Furthermore, the large-particle aluminum oxide is spherical aluminum oxide with an average particle size of 40 μm-50 μm, for example, 40 μm, 45 μm, 50 μm, etc.

[0031] In the above, the use of alumina with different particle sizes can increase the filling volume of the gel, make it have a higher thermal conductivity system, reduce thermal resistance, and thus make the gel have higher tensile strength, elongation at break and thermal conductivity.

[0032] The second object of the present invention is achieved by adopting the following technical solution: A method for preparing a two-component thermally conductive gel with a low expansion coefficient comprises the following steps: S1: Vinyl silicone oil, MQ resin, negative thermal expansion agent, small-particle alumina, medium-particle alumina, large-particle alumina, colorant and platinum catalyst are mixed uniformly by planetary stirring at room temperature to obtain premix A; S2: Vinyl silicone oil, MQ resin, side hydrogen silicone oil, end hydrogen silicone oil, negative thermal expansion agent, small-particle alumina, medium-particle alumina and large-particle alumina are mixed uniformly by planetary stirring at room temperature to obtain premix B; S3: When in use, premix A and premix B are mixed to obtain a two-component thermally conductive gel with a low expansion coefficient.

[0033] Further, in step S1, the mixing of premix A is carried out under vacuum conditions; wherein the vacuum degree of the vacuum condition is 0.08 MPa-0.1 MPa (for example, it can be 0.08 MPa, 0.085 MPa, 0.09 MPa, 0.095 MPa or 0.1 MPa, etc.), and the mixing time is 20 min-60 min (for example, it can be 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min or 60 min, etc.).

[0034] Further, in step S2, the mixing of premix B is carried out under vacuum conditions; wherein the vacuum degree of the vacuum condition is 0.08 MPa-0.1 MPa (for example, it can be 0.08 MPa, 0.085 MPa, 0.09 MPa, 0.095 MPa or 0.1 MPa, etc.), and the mixing time is 20 min-60 min (for example, it can be 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min or 60 min, etc.).

[0035] Further, in step S3, the mixing time of premix A and premix B is 1 min-20 min, for example, it can be 1 min, 2 min, 4 min, 6 min, 8 min, 10 min, 12 min, 14 min, 16 min, 18 min or 20 min.

[0036] Compared with the prior art, the present invention has the following beneficial effects: 1. The two-component thermally conductive gel of the present invention is obtained by rationally using components such as vinyl silicone oil, silicone resin such as MQ resin, hydrogen-containing silicone oil such as side hydrogen-containing silicone oil and end hydrogen-containing silicone oil, negative thermal expansion agent and aluminum oxide of different sizes to obtain a two-component silicone thermally conductive gel with excellent mechanical properties and low thermal expansion coefficient.

[0037] 2. The two-component silicone thermally conductive gel of the present invention has the following properties: tensile strength 0.4 Mpa -1.0 Mpa, thermal conductivity 2.0 W / m•K-4.0 W / m•K, thermal expansion coefficient <100 ppm / ℃, hardness 70 Shore oo-75 Shore oo, and is very suitable for the field of mid-to-high-end electronic equipment, especially for filling and heat dissipation of precision electronic equipment. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0039] The sources of some components in the embodiments and comparative examples are as follows: Vinyl-terminated polydimethylsiloxane: Hubei Handafei Biotechnology Co., Ltd., CAS 68083-19-2; Polyvinyl silicone oil: Wuhan Kemik Biopharmaceutical Technology Co., Ltd.; Custer Catalyst: Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.; Side chain hydrogen-containing silicone oil: Jining Fangyu Chemical Co., Ltd.; End-chain hydrogenated silicone oil: Jining Fangyu Chemical Co., Ltd.; Zirconium tungstate or yttrium tungstate: Wuhan Huaxiang Kejie Biotechnology Co., Ltd.; Spherical alumina: Qinghe County Dingze Wear-Resistant Materials Co., Ltd.

[0040] In the following embodiments, the preparation method of the two-component thermally conductive gel is: S1: Vinyl silicone oil, MQ resin, negative thermal expansion agent, small-particle alumina, medium-particle alumina, large-particle alumina, colorant and platinum catalyst are mixed under vacuum conditions with a vacuum degree of 0.08 MPa and planetary stirring for 30 min to obtain premix A; S2: Vinyl silicone oil, MQ resin, side hydrogen silicone oil, end hydrogen silicone oil, negative thermal expansion agent, small-particle alumina, medium-particle alumina and large-particle alumina are mixed under vacuum conditions with a vacuum degree of 0.08 MPa and planetary stirring for 30 min to obtain premix B; S3: When in use, premix A and premix B are mixed for 5 minutes.

[0041] A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0042] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0043] Example 2 Changing the amount of vinyl silicone oil A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 15 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 10 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0044] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0045] Example 3 Changing the amount of MQ resin A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 3 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 3 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0046] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0047] Example 4 Changing the amount of negative thermal expansion agent A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 15 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 15 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0048] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0049] Example 5 Changing the amount of side hydrogen silicone oil A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1.5 parts of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0050] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0051] Example 6 Changing the amount of terminal hydrogen-containing silicone oil A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 1.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0052] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 0.4μm; the medium particle size alumina is spherical alumina with an average particle size of 8μm, and the large particle size alumina is spherical alumina with an average particle size of 40μm.

[0053] Example 7 Changing the particle size of alumina A two-component thermally conductive gel comprises a component A and a component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0054] Among them, the vinyl silicone oil is terminal vinyl polydimethylsiloxane, and its viscosity at 25°C is 400Pa.s; the MQ resin is polyvinyl silicone oil, and its vinyl content is 3wt%; the platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm; the side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%; the terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%; the colorant is carbon black; the negative thermal expansion agent is yttrium tungstate, and its average particle size is 0.4μm; the small particle size alumina is spherical alumina with an average particle size of 1μm; the medium particle size alumina is spherical alumina with an average particle size of 10μm, and the large particle size alumina is spherical alumina with an average particle size of 50μm.

[0055] The comparative examples are shown below: Comparative Example 1 Different from Example 1, component A of the thermally conductive gel of comparative document 1 does not contain MQ resin and negative thermal expansion agent, and component B does not contain MQ resin, negative thermal expansion agent and terminal hydrogen-containing silicone oil.

[0056] Specifically, the thermally conductive gel includes component A and component B; The A component includes the following components in parts by weight: 9 parts of vinyl silicone oil, 0.01 parts of colorant, 16 parts of small-particle aluminum oxide, 30 parts of medium-particle aluminum oxide, 45 parts of large-particle aluminum oxide, and 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 7.7 parts of vinyl silicone oil, 1.3 parts of hydrogenated silicone oil, 16 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0057] The other component requirements and preparation methods are the same as those of Example 1.

[0058] Comparative Example 2 Different from Example 1, component A of the thermal conductive gel of Comparative Document 2 does not contain MQ resin, and component B does not contain MQ resin.

[0059] Specifically, the thermally conductive gel includes component A and component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle aluminum oxide, 30 parts of medium-particle aluminum oxide, 45 parts of large-particle aluminum oxide, and 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0060] The other component requirements and preparation methods are the same as those of Example 1.

[0061] Comparative Example 3 Different from Example 1, component A of the thermally conductive gel of Comparative Document 3 does not contain a negative thermal expansion agent, and component B does not contain a negative thermal expansion agent.

[0062] Specifically, the thermally conductive gel includes component A and component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 7 parts of small-particle aluminum oxide, 30 parts of medium-particle aluminum oxide, 45 parts of large-particle aluminum oxide, and 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0063] The other component requirements and preparation methods are the same as those of Example 1.

[0064] Comparative Example 4 Different from Example 1, component B of the thermal conductive gel of Reference Document 4 does not contain terminal hydrogen-containing silicone oil.

[0065] Specifically, the thermally conductive gel includes component A and component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 9 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogen silicone oil, 9 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0066] The other component requirements and preparation methods are the same as those of Example 1.

[0067] Comparative Example 5 Different from Example 1, the content of the negative thermal expansion agent in the thermally conductive gel of Reference Document 5 is increased.

[0068] Specifically, the thermally conductive gel includes component A and component B; The A component includes the following components in parts by weight: 7.5 parts of vinyl silicone oil, 1.5 parts of MQ resin, 0.01 parts of colorant, 20 parts of negative thermal expansion agent, 7 parts of small-particle alumina, 30 parts of medium-particle alumina, 45 parts of large-particle alumina, 0.02 parts of platinum catalyst; The B component includes the following components in parts by weight: 6 parts of vinyl silicone oil, 1.5 parts of MQ resin, 1 part of side hydrogenated silicone oil, 0.5 parts of end hydrogenated silicone oil, 20 parts of negative thermal expansion agent, 7 parts of small particle size alumina, 30 parts of medium particle size alumina, and 45 parts of large particle size alumina.

[0069] The other component requirements and preparation methods are the same as those of Example 1.

[0070] Performance Testing 1. Test objects: Examples 1-7, Comparative Examples 1-5.

[0071] 2. During the test, the thermal conductivity is measured in accordance with "ASTM D 5470-01 Characterization test for testing the thermal conductivity properties of thin thermally conductive solid electrical insulating materials", the tensile strength is measured in accordance with "GBT 528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", the test standard of Shore 00 hardness is mainly based on ASTM D2240 standard, and the thermal expansion coefficient is measured in accordance with "ASTM E831-06".

[0072] 3. The test results are shown in Table 1 below.

[0073] Table 1 project Thermal conductivity W / mk Hardness Shoreoo Tensile strength MPa Thermal expansion coefficient ppm / ℃ Example 1 2.9 71 0.6 85 Example 2 (Enlarged Vinyl Silicone Oil) 2.5 73 0.8 90 Example 3 (Enlarged MQ resin) 2.3 73 0.9 98 Example 4 (Increasing negative thermal expansion agent) 4.0 74 1.0 62 Example 5 (Enlarged side hydrogen-containing silicone oil) 3.2 70 0.9 89 Example 6 (enlarged end hydrogen-containing silicone oil) 3.3 70 0.9 88 Example 7 (Increasing the particle size of alumina) 2.0 75 1.0 75 Comparative Example 1 (Component A does not contain MQ resin and negative thermal expansion agent, and component B does not contain MQ resin, negative thermal expansion agent and terminal hydrogen-containing silicone oil) 3.0 70 0.3 170 Comparative Example 2 (Component A does not contain MQ resin, and component B does not contain MQ resin) 2.8 71 0.4 106 Comparative Example 3 (no negative thermal expansion agent, component B does not contain a negative thermal expansion agent) 3.0 70 0.7 162 Comparative Example 4 (Component B does not contain terminal hydrogen-containing silicone oil) 2.8 71 0.5 168 Comparative Example 5 (increasing the negative thermal expansion agent to 20 parts) 1.6 82 0.3 82 The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A two-component thermally conductive gel with a low expansion coefficient, characterized in that: It includes component A and component B; The A component includes the following components in parts by weight: 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.01-0.05 parts of colorant, 5-15 parts of negative thermal expansion agent, 5-10 parts of small-particle alumina, 20-35 parts of medium-particle alumina, 40-60 parts of large-particle alumina, 0.01-0.05 parts of platinum catalyst; The B component includes the following components in parts by weight: 5-15 parts of vinyl silicone oil, 0.5-3 parts of MQ resin, 0.3-1.5 parts of side hydrogen-containing silicone oil, 0.3-1.5 parts of end hydrogen-containing silicone oil, 5-15 parts of negative thermal expansion agent, 5-10 parts of small particle size alumina, 20-35 parts of medium particle size alumina, 40-60 parts of large particle size alumina.

2. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The vinyl silicone oil is vinyl-terminated polydimethylsiloxane, and its viscosity at 25° C. is 300 Pa.s-1000 Pa.s.

3. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The MQ resin is polyvinyl silicone oil, and its vinyl content is 2wt%-6wt%.

4. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The platinum catalyst is a Custer catalyst, and its Pt content is 1000ppm-5000ppm.

5. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The side hydrogen-containing silicone oil is a side chain hydrogen-containing silicone oil, and its hydrogen content is 0.1wt%-0.5wt%.

6. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The terminal hydrogen-containing silicone oil is a terminal chain hydrogen-containing silicone oil, and its hydrogen content is 0.05wt%-0.1wt%.

7. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The colorant is an inorganic filler with a coloring effect. Preferably, the inorganic filler is at least one of carbon black, red iron oxide, and mica iron oxide gray.

8. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The negative thermal expansion agent is at least one of zirconium tungstate and yttrium tungstate, and its average particle size is 0.4 μm-2 μm.

9. The two-component thermally conductive gel with a low expansion coefficient according to claim 1, characterized in that: The small-particle alumina is spherical alumina with an average particle size of 0.4 μm-1 μm, the medium-particle alumina is spherical alumina with an average particle size of 5 μm-10 μm, and the large-particle alumina is spherical alumina with an average particle size of 40 μm-50 μm.

10. A method for preparing a two-component thermally conductive gel with a low expansion coefficient as claimed in any one of claims 1 to 9, characterized in that: The steps include: S1: Vinyl silicone oil, MQ resin, negative thermal expansion agent, small-particle alumina, medium-particle alumina, large-particle alumina, colorant and platinum catalyst are mixed uniformly by planetary stirring at room temperature to obtain premix A; S2: Vinyl silicone oil, MQ resin, side hydrogen silicone oil, end hydrogen silicone oil, negative thermal expansion agent, small-particle alumina, medium-particle alumina and large-particle alumina are mixed uniformly by planetary stirring at room temperature to obtain premix B; S3: When in use, premix A and premix B are mixed to obtain a two-component thermally conductive gel with a low expansion coefficient.