Preparation method of 12W single-component curable heat-conducting gel with high extrusion rate

Abstract

The invention relates to the technical field of preparation of heat-conducting gel, in particular to a preparation method of 12W single-component curable heat-conducting gel with a high extrusion rate. The preparation method comprises the following steps: carrying out hydrosilylation reaction on trimethoxy single-end-capped vinyl-side silicone oil and end hydrogen-containing silicone oil, adding a heat-conducting filler to form a mixture, carrying out high-temperature treatment to hydrolyze hydroxyl and trimethoxy on the surface of mixture powder to generate methanol, and volatilizing at high temperature; meanwhile, D3-D20 in the organic matter is also removed in a high-temperature environment, so that the vinyl silicone oil can directly wrap the surface of the heat-conducting powder, the viscosity of an oil-powder mixture is reduced, and the heat conductivity coefficient is further improved. The invention provides a preparation method of 12W single-component curable heat-conducting gel with a high extrusion rate.

Description

Technical Field

[0001] The invention relates to the technical field of thermal conductive gel preparation, and in particular to a method for preparing a single-component curable thermal conductive gel with a high extrusion rate of 12W. Background Art

[0002] The existing 12W thermal conductive gels on the market have the problem of too low extrusion rate, which is usually lower than the industry standard, which directly affects its efficiency and convenience in practical applications. In addition, the existing thermal conductive gels contain a large amount of D3-D20 small molecule volatiles, whose chemical names are hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, etc. These volatiles will have adverse effects on reliability and long-term use. Due to the presence of these volatiles, the thermal conductive gel is easy to dry and harden after reliability testing, resulting in performance degradation and failure to meet the requirements of high-quality applications.

[0003]

[0004]

[0005] The main problems of the existing 12W thermal conductive gel are: (1) Low extrusion rate: This makes it difficult to operate in actual applications, affecting production efficiency. (2) High content of D3-D20 small molecule volatiles: They are easy to evaporate in high temperature environments, causing the thermal conductive gel to dry and harden after reliability testing, thereby reducing the reliability and service life of the product. (3) Insufficient reliability: The presence of these volatiles will also affect the long-term performance of the thermal conductive gel, making it easy to fail in harsh environments such as high temperature and high humidity. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a method for preparing a single-component curable thermally conductive gel with a high extrusion rate of 12W.

[0007] The technical scheme adopted by the present invention is: a preparation method of a high extrusion rate 12W single-component curable thermally conductive gel, wherein trimethoxy mono-terminated side vinyl silicone oil and end hydrogen silicone oil are subjected to a silylation reaction, a thermally conductive filler is added to form a mixture, and then the hydroxyl group and the trimethoxy group on the surface of the mixture powder are hydrolyzed to generate methanol and volatilize at high temperature after high temperature treatment, and D3-D20 in the organic matter is also removed under high temperature environment, so that the vinyl silicone oil can directly wrap the surface of the thermally conductive powder, reduce the viscosity of the oil-powder mixture, and then improve the thermal conductivity.

[0008] As a further improvement of the present invention, the thermal conductive filler includes nano-aluminum oxide, aluminum nitride, and diamond.

[0009] As a further improvement of the present invention, the particle size of the nano-aluminum oxide is less than 1 micron, the particle size of the aluminum nitride is 10 microns, and the particle size of the diamond is 60 microns.

[0010] As a further improvement of the present invention, the viscosity of the vinyl silicone oil is 100 cps, and the viscosity of the hydrogen-containing silicone oil is 50 cps.

[0011] As a further improvement of the present invention, the vinyl silicone oil, hydrogen-containing silicone oil, nano-alumina, aluminum nitride, and diamond are counted in parts by weight: vinyl silicone oil accounts for 96-100 parts, hydrogen-containing silicone oil accounts for 1-3 parts, nano-alumina accounts for 250-750 parts, aluminum nitride accounts for 250-750 parts, and diamond accounts for 1250-1500 parts.

[0012] As a further improvement of the present invention, the temperature of the high temperature treatment is controlled between 120° C. and 180° C., and the duration is not less than 4 hours.

[0013] Beneficial effects of the present invention: (1) Improving extrusion rate: The present invention uses trimethoxy mono-terminated side vinyl silicone oil and end hydrogen silicone oil to carry out silylation reaction, and then undergoes high-temperature treatment to make the hydroxyl groups on the surface of the thermal conductive filler react with the trimethoxy groups to generate methanol and volatilize, thereby significantly reducing the viscosity of the mixture, so that the prepared thermal conductive gel has a higher extrusion rate of up to or exceeding 40 g / min, greatly improving production efficiency and ease of application.

[0014] (2) Removal of D3-D20 small molecule volatiles: The high temperature treatment step of the present invention can effectively remove D3-D20 small molecule volatiles in organic matter, making its content less than 30 ppm, significantly improving the reliability and long-term performance of the thermal conductive gel, and avoiding the performance degradation and failure problems caused by the presence of volatiles in harsh environments such as high temperature and high humidity.

[0015] (3) Optimizing the ratio and particle size of thermally conductive fillers: The present invention selects nano-alumina with a particle size of less than 1 micron, aluminum nitride with a particle size of 10 microns, and diamond with a particle size of 60 microns, and optimizes their ratio so that the thermally conductive fillers can be better distributed and wrapped in the mixture, which not only improves the thermal conductivity of the thermally conductive gel to more than 12 W / mK, but also enhances its overall performance and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural diagram of trimethoxy mono-terminated side vinyl silicone oil in a method for preparing a high extrusion rate 12W single-component curable thermally conductive gel of the present invention;

[0017] Figure 2 It is a structural diagram of the end-hydrogenated silicone oil of a method for preparing a 12W single-component curable thermally conductive gel with a high extrusion rate of the present invention;

[0018] Figure 3 It is a schematic diagram of the hydrosilylation reaction of a method for preparing a 12W single-component curable thermally conductive gel with a high extrusion rate according to the present invention;

[0019] Figure 4 It is a reaction principle diagram of a method for preparing a single-component curable thermally conductive gel with a high extrusion rate of 12W according to the present invention. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] The invention provides a preparation method of a single-component curable thermally conductive gel with a high extrusion rate of 12W. The method is characterized in that: trimethoxy mono-terminated side vinyl silicone oil and end hydrogen silicone oil are subjected to a silylation reaction, a thermally conductive filler is added to form a mixture, and then a hydroxyl group and a trimethoxy group on the surface of the mixture powder are hydrolyzed to generate methanol after high-temperature treatment and volatilized at high temperature, and D3-D20 in organic matter is also removed under high-temperature environment, so that the vinyl silicone oil can directly wrap the surface of the thermally conductive powder, reduce the viscosity of the oil-powder mixture, and further improve the thermal conductivity.

[0022] The thermal conductive filler in the present invention includes nano-alumina, aluminum nitride, and diamond. The particle size of nano-alumina is less than 1 micron, the particle size of aluminum nitride is 10 microns, and the particle size of diamond is 60 microns. The viscosity of vinyl silicone oil is 100 cps, and the viscosity of hydrogen silicone oil is 50 cps. The temperature of high temperature treatment is controlled between 120°C and 180°C, and the duration is not less than 4 hours.

[0023] The weight proportions of vinyl silicone oil, hydrogenated silicone oil, nano-alumina, aluminum nitride and diamond in the present invention are as follows: vinyl silicone oil accounts for 96-100 parts, hydrogenated silicone oil accounts for 1-3 parts, nano-alumina accounts for 250-750 parts, aluminum nitride accounts for 250-750 parts and diamond accounts for 1250-1500 parts.

[0024] Preparation tests were carried out according to the above method, and the test cases included Example 1, Example 2, Example 3, Example 4, Example 5 and Comparative Example 1, as shown in the following table.

[0025]

[0026] From the test results of the above examples, it can be clearly seen that the preparation method of the high extrusion rate 12W single-component curable thermally conductive gel of the present invention has significant advantages:

[0027] (1) Example 1: When 98g of vinyl silicone oil with a viscosity of 100cps, 2g of hydrogenated silicone oil with a viscosity of 50cps, 500g of nano-alumina with a particle size of less than 1 micron, 750g of aluminum nitride with a particle size of 10 microns, and 1250g of diamond with a particle size of 60 microns were used and subjected to high temperature treatment (the temperature was controlled between 120°C and 180°C for a duration of not less than 4 hours), the thermal conductivity of the prepared thermally conductive gel reached 12.61W / mK, the extrusion rate reached 43g / min, and the content of D3-D20 was less than 30ppm. This result fully meets the performance requirements of the product, especially the high thermal conductivity and high extrusion rate, and greatly improves the production efficiency and application convenience.

[0028] (2) Comparison without heat treatment: Example 6 was not subjected to high temperature treatment, and its thermal conductivity was 12.58 W / mK, the extrusion rate was 38 g / min, and the content of D3-D20 was 267 ppm. Compared with Example 1, although its thermal conductivity was close, the extrusion rate and the content of D3-D20 were obviously not up to standard. This shows that the high temperature treatment step is crucial for removing D3-D20 small molecule volatiles and improving the extrusion rate.

[0029] (3) Optimizing the ratio of thermal conductive fillers: By comparing the various examples, it can be seen that the ratio of thermal conductive fillers has a significant effect on thermal conductivity and extrusion rate. For example, the ratio of thermal conductive fillers in Example 3 and Example 4 is quite different, resulting in unsatisfactory thermal conductivity and extrusion rate. The ratio and particle size selected in Example 1 and Example 6 are the best choices, which can ensure that the performance of the thermal conductive gel is optimal.

[0030] In summary, the preparation method of the 12W single-component curable thermally conductive gel with high extrusion rate of the present invention significantly improves the thermal conductivity, extrusion rate and reliability of the thermally conductive gel by optimizing the formula and process steps, especially removing the D3-D20 small molecule volatiles during the high temperature treatment process. This makes the thermally conductive gel of the present invention have a wider application prospect and better market competitiveness in high-performance application fields such as the optical communication industry, automotive radar, machine vision system, and security industry.

[0031] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a single-component curable thermally conductive gel with a high extrusion rate of 12W, characterized in that: The trimethoxy mono-terminated side vinyl silicone oil and the end hydrogen silicone oil are subjected to a silylation reaction, and a thermal conductive filler is added to form a mixture. The mixture is then treated at high temperature to hydrolyze the hydroxyl and trimethoxy groups on the surface of the mixture powder to generate methanol, which evaporates at high temperature. At the same time, D3-D20 in the organic matter is also removed under high temperature conditions, so that the vinyl silicone oil can directly wrap the surface of the thermal conductive powder, reduce the viscosity of the oil-powder mixture, and thus improve the thermal conductivity.

2. The method for preparing a 12W single-component curable thermally conductive gel with a high extrusion rate according to claim 1, characterized in that: The thermal conductive filler includes nano-aluminum oxide, aluminum nitride and diamond.

3. The method for preparing a high extrusion rate 12W single-component curable thermally conductive gel according to claim 2, characterized in that: The particle size of the nano-aluminum oxide is less than 1 micron, the particle size of the aluminum nitride is 10 microns, and the particle size of the diamond is 60 microns.

4. The method for preparing a high extrusion rate 12W single-component curable thermally conductive gel according to claim 1, characterized in that: The viscosity of the vinyl silicone oil is 100 cps, and the viscosity of the hydrogen-containing silicone oil is 50 cps.

5. The method for preparing a high extrusion rate 12W single-component curable thermally conductive gel according to claim 3, characterized in that: The vinyl silicone oil, hydrogen-containing silicone oil, nano-alumina, aluminum nitride and diamond are counted in parts by weight: vinyl silicone oil accounts for 96-100 parts, hydrogen-containing silicone oil accounts for 1-3 parts, nano-alumina accounts for 250-750 parts, aluminum nitride accounts for 250-750 parts, and diamond accounts for 1250-1500 parts.

6. The method for preparing a high extrusion rate 12W single-component curable thermally conductive gel according to claim 1, characterized in that: The temperature of the high temperature treatment is controlled between 120° C. and 180° C., and the duration is not less than 4 hours.

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