Preparation method and application of heat-resistant high-thermal-conductivity modified simethicone

Abstract

The invention relates to a preparation method and application of heat-resistant high-thermal-conductivity modified dimethyl silicone oil. Adding a certain proportion of phenylalkoxysilane into dimethyl silicone oil, blowing in water vapor, heating to 60-70 DEG C, stirring, adding zirconium caprylate, heating to 100-180 DEG C, continuously blowing in high-purity nitrogen, preserving heat, stirring and dispersing uniformly to obtain a heat-resistant additive; the preparation method comprises the following steps: adding a liquid metal composite material into dimethyl silicone oil while stirring, heating to 160-230 DEG C, dropwise adding a heat-resistant additive, continuously blowing high-purity nitrogen, and continuously stirring and homogenizing to obtain the metal bright-color modified dimethyl silicone oil. In the dimethyl silicone oil, the modified dimethyl silicone oil can be obtained by taking methyl phenyl alkoxy silane, zirconium octoate, a liquid metal composite material and the like as modifiers, the thermal conductivity can be improved to 4-8W / m.K, the weight loss mass fraction at 350 DEG C * 30min is less than 1.0%, and the heat-resistant stability and the thermal conductivity are greatly improved.

Description

Technical Field

[0001] The invention relates to a preparation method and production technology of modified dimethyl silicone oil, and in particular to a preparation method and application of heat-resistant and high-thermal-conductivity modified dimethyl silicone oil. Background Art

[0002] Silicone oil has good thermal oxidation resistance, low vapor pressure, and high flash point, and can be used as various high-temperature baths and high-temperature heat carriers. Dimethyl silicone oil can be used for a long time in the air at temperatures below 175°C, and can also be used for a long time at 200-250°C in a closed system.

[0003] In a closed system, the operating temperature of Dow's Syltherm 800 silicone oil heat transfer oil is -40 ℃ ~ 400 ℃, and the operating temperature of Germany's Wacker's HELISOL silicone oil heat transfer oil is currently -40 ℃ ~ 425 ℃. With the advancement and development of industrial technology, the application fields of high-temperature resistant silicone oil will continue to expand, such as automotive clutch oil, high-temperature resistant mold release agent, ultra-high temperature atomized silicone oil, solar power generation heat collection heat transfer oil carrier and other fields will also increase the demand for the use of high-temperature heat transfer silicone oil, and at the same time, the requirements for high-temperature thermal stability and service life of silicone oil will be further improved.

[0004] There are studies on phenyl silicone oil in the literature, and its temperature resistance is 20-50℃ higher than that of methyl silicone oil, but the industrial scale of phenyl monomer is limited.

[0005] Patent TW202126611A specifically introduces the preparation method of organic cerium heat-resistant agent, which is used by relevant researchers to modify silicone oil and silicone rubber. Patent CN111154141A adds organic metal salts to organic silicon oligomers to make heat-resistant agents, which are further used in polymer modification. Patent CN114752362A adds ionic liquids and nano-metal salts to carbon-based heat transfer oil to prepare wide-temperature carbon-based modified heat transfer oil.

[0006] Although the above patents and documents involve methods for preparing heat-resistant agents and heat-conducting oils, they do not yet involve modified dimethyl silicone oils that have both good temperature resistance and good thermal conductivity.

[0007] In order to improve the temperature resistance and thermal conductivity of dimethyl silicone oil, give it better functionality and expand its application areas, this patent provides a preparation method and application of a temperature-resistant and high-thermal-conductivity modified dimethyl silicone oil. Summary of the invention

[0008] In order to improve the temperature resistance and thermal conductivity of dimethyl silicone oil, give it better functionality and expand its application areas, this patent provides a preparation method and application of a temperature-resistant and high-thermal-conductivity modified dimethyl silicone oil.

[0009] The present invention adopts the following technical solution: (1) Preparation of heat-resistant additives: add a certain proportion of phenyl alkoxy silane to dimethyl silicone oil, blow in a small amount of water vapor, gradually raise the temperature to 60-70°C and stir for 0.5-2h, add a certain proportion of zirconium octanoate, raise the temperature to 100-180°C, continue to blow in a small amount of high-purity nitrogen, keep warm for 1-3h and stir to disperse evenly to obtain a heat-resistant additive.

[0010] (2) Preparation of modified dimethyl silicone oil: add a certain proportion of liquid metal composite material to dimethyl silicone oil while stirring, heat to 160-230°C, gradually add a certain proportion of heat-resistant additives, continue to blow in a small amount of high-purity nitrogen, continue stirring and homogenizing for 2-6 hours, and obtain modified dimethyl silicone oil with a metallic bright color.

[0011] The dimethyl silicone oil has a viscosity of 20-500 cSt and a volatile matter of less than 0.20%.

[0012] The phenylalkoxysilane includes one or more of methylphenyldialkoxysilane, phenyltrialkoxysilane, diphenyldialkoxysilane, etc., accounting for 1-5wt% of the heat-resistant additive.

[0013] The zirconium octanoate accounts for 0.5-2 wt % of the heat-resistant additive A.

[0014] The high-purity nitrogen has a dew point not higher than -60°C and a water content not higher than 10ppm.

[0015] The liquid metal composite material can be one or more of a gallium-based alloy composite material (Fill-LM 2500), a bismuth-based alloy composite material (Fill-LMS 7200), and an indium-based alloy composite material (Fill-LM SW8000) (Suzhou Taijinuo New Material Technology Co., Ltd.), accounting for 0.5-2 wt % of the amount of dimethyl silicone oil used.

[0016] The heat-resistant additive accounts for 0.1-2 wt % of the amount of dimethyl silicone oil used. Through the above technical solutions, the present invention has the following technical effects: Heat-resistant additives with phenyl alkoxysilane added can effectively remove hydroxyl groups in silicone oil and zirconium octanoate, improve the compatibility of zirconium octanoate with silicone oil, increase the storage stability of heat-resistant additives and maintain fluidity. Heat-resistant additives modified with phenyl alkoxysilane and zirconium octanoate are added to dimethyl silicone oil. First, hydroxyl groups in silicone oil can be eliminated to increase temperature stability; second, zirconium octanoate can inhibit the production of cyclosiloxane, increase the flash point of silicone oil and improve heat resistance; third, liquid metal composite materials are added to silicone oil. Liquid metal composite materials are better dispersed in silicone oil, which can greatly improve the thermal conductivity of silicone oil. DETAILED DESCRIPTION

[0017] Example 1 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenyl dimethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, continue to blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A1.

[0018] Example 2 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenyldiethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A2.

[0019] Example 3 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg diphenyldiethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A3.

[0020] Example 4 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg phenyltriethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A4.

[0021] Example 5 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.2kg methylphenyldiethoxysilane and 0.2kg diphenyldimethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A5.

[0022] Comparative Example 1 In the heat-resistant additive A1, no phenyl alkoxy silane was added, and the rest was the same as in Example 1.

[0023] The experimental results of Examples 1-5 and Comparative Example 1 and the heat-resistant addition A are shown in Table 1.

[0024] Table 1 Results of heat-resistant additive A of Examples 1-5 and Comparative Example 1

[0025] Note: 1. For heat-resistant additive A, the lower the viscosity, the better; and the smaller the relative value of 1440h hydroxyl group, the better.

[0026] Example 6 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenylethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.1kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, continue to blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A6.

[0027] Example 7 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenylethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.2kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A7.

[0028] Example 8 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenylethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.3kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A8.

[0029] Example 9 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenylethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.4kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A9.

[0030] Example 10 20kgKM-50LV dimethyl silicone oil (Yichang Kelin Silicon Material Co., Ltd., brand KM-50LV, viscosity 51cSt, volatile matter 0.10%), add 0.4kg methylphenylethoxysilane under stirring, blow in water vapor at 1-5L / min, heat to 65℃ at 3-5℃ / min, and stir at constant temperature for 1h. Continue to add 0.6kg zirconium octanoate, heat to 165-170℃ at 3-5℃ / min, blow in 99.99% nitrogen at 10-15L / min, keep stirring for 2h, and obtain heat-resistant additive A10.

[0031] Comparative Example 2 In the heat-resistant additive A, no zirconium octanoate is added, and the rest is the same as in Example 6.

[0032] The experimental results of Examples 6-10 and Comparative Example 2 and the heat-resistant additive A are shown in Table 2.

[0033] Table 2 Results of heat-resistant additive A of Examples 6-10 and Comparative Example 2 Test method: Refer to the authoritative work in the silicone industry, Huang Wenrun. Silicone oil and its applications [M]. Chengdu: Sichuan Science and Technology Press, 2018, P87-91.

[0034] Table 2 Results of heat-resistant additive A of Examples 6-10 and Comparative Example 2

[0035] Embodiment 11 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.2kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F11 with metallic bright color.

[0036] Example 12 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.6kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F12 with metallic bright color.

[0037] Embodiment 13 Preparation of heat-resistant additives is the same as in Example 1. Take 40 kg of KM-50LV dimethyl silicone oil, add 0.8 kg of gallium-based alloy composite material (density 5-6 g / cm3, thermal conductivity 24.5 W / mK, viscosity 4500 cP) under stirring, heat to 185-190°C, slowly add 0.4 kg of heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15 L / min, continue stirring and homogenizing for 4 hours, and obtain modified dimethyl silicone oil F13 with metallic bright color.

[0038] Embodiment 14 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 1.0kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F14 with metallic bright color.

[0039] Embodiment 15 Preparation of heat-resistant additives is the same as in Example 1. Take 40 kg of KM-50LV dimethyl silicone oil, add 0.6 kg of bismuth-based alloy composite material (density 7.5-8.1 g / cm3, thermal conductivity 68.3 W / mK, viscosity 7200 cP) under stirring, heat to 185-190°C, slowly add 0.4 kg of heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15 L / min, continue stirring and homogenizing for 4 hours, and obtain modified dimethyl silicone oil F14 with metallic bright color.

[0040] Example 16 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.6kg indium-based alloy composite material (density 6.5-7.5g / cm3, thermal conductivity 82.0W / mK) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F14 with metallic bright color.

[0041] Comparative Example 3 After the gallium-based alloy composite material is added, stirring is performed at room temperature without heating, and conventional stirring is performed without homogenization. Other aspects are the same as those of Example 12.

[0042] Comparative Example 4 No liquid metal gallium-based alloy composite material is added, and the rest is the same as in Example 12.

[0043] The results of the modified dimethyl silicone oil F of Examples 11-14 and Comparative Examples 3-4 are shown in Table 3. Table 3 Results of modified dimethyl silicone oil F of Examples 11-14 and Comparative Examples 3-4

[0044] Note: 1. For the non-uniform fluid in Example 3, the viscosity difference increases at different locations, and the thermal conductivity varies greatly at different points.

[0045] 2. The higher the temperature when TGA weight loss is 10%, the better the heat resistance.

[0046] Embodiment 15 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.6kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.04kg heat-resistant additive A1, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F15 with metallic bright color.

[0047] Example 16 Preparation of heat-resistant additives is the same as in Example 1. Take 40 kg of KM-50LV dimethyl silicone oil, add 0.6 kg of gallium-based alloy composite material (density 5-6 g / cm3, thermal conductivity 24.5 W / mK, viscosity 4500 cP) under stirring, heat to 185-190°C, slowly add 0.4 kg of heat-resistant additive A4, continue to blow 99.99% nitrogen at 10-15 L / min, continue stirring and homogenizing for 4 hours, and obtain modified dimethyl silicone oil F16 with metallic bright color.

[0048] Embodiment 17 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.6kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A5, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F17 with metallic bright color.

[0049] Embodiment 18 Preparation of heat-resistant additives is the same as in Example 1. Take 40 kg of KM-50LV dimethyl silicone oil, add 0.6 kg of gallium-based alloy composite material (density 5-6 g / cm3, thermal conductivity 24.5 W / mK, viscosity 4500 cP) under stirring, heat to 185-190°C, slowly add 0.4 kg of heat-resistant additive A8, continue to blow 99.99% nitrogen at 10-15 L / min, continue stirring and homogenizing for 4 hours, and obtain modified dimethyl silicone oil F18 with metallic bright color.

[0050] Embodiment 19 Preparation of heat-resistant additives is the same as in Example 1. Take 40kg KM-50LV dimethyl silicone oil, add 0.6kg gallium-based alloy composite material (density 5-6g / cm3, thermal conductivity 24.5W / mK, viscosity 4500cP) under stirring, heat to 185-190°C, slowly add 0.4kg heat-resistant additive A10, continue to blow 99.99% nitrogen at 10-15L / min, continue stirring and homogenizing for 4h, and obtain modified dimethyl silicone oil F19 with metallic bright color.

[0051] Comparative Example 5 No heat-resistant additive is added, and the rest is the same as in Example 15.

[0052] The experimental results of modified dimethyl silicone oil F of Examples 15-19 and Comparative Example 5 are shown in Table 4.

[0053] Table 4 Experimental results of modified dimethyl silicone oil F of Examples 15-19 and Comparative Example 5

[0054] From Tables 1-4, we can see that the modified dimethyl silicone oil F has a viscosity of 40-60 cSt, the thermal conductivity can be increased to 4-8 W / m·K, the weight loss mass fraction at 350℃*30min is less than 1.0%, and the heat resistance stability and thermal conductivity performance are greatly improved.

[0055] The specific embodiments in this application are merely explanations of this application and are not limitations of this application. After reading this specification, those skilled in the art may make modifications to the embodiments without creative contribution as needed.

Claims

1. A method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil, characterized in that: The steps include: (1) Preparation of heat-resistant additive A: Add a certain proportion of phenyl alkoxy silane to dimethyl silicone oil, blow in water vapor, heat to 60-70°C, stir, add zirconium octanoate, heat to 100-180°C, continue to blow in high-purity nitrogen, keep warm and stir until evenly dispersed, and obtain a heat-resistant additive; (2) Preparation of modified dimethyl silicone oil: Add liquid metal composite material to dimethyl silicone oil while stirring, heat to 160-230°C, add heat-resistant additives dropwise, continue to blow in high-purity nitrogen, continue to stir and homogenize, and obtain modified dimethyl silicone oil with a metallic bright color.

2. The method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil according to claim 1, characterized in that: The dimethyl silicone oil has a viscosity of 20-500 cSt and a volatile matter of less than 0.20%.

3. The method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil according to claim 1, characterized in that: The phenylalkoxysilane includes one or more of methylphenyldialkoxysilane, phenyltrialkoxysilane, and diphenyldialkoxysilane, accounting for 1-5wt% of the heat-resistant additive.

4. The method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil according to claim 1, characterized in that: The zirconium octoate accounts for 0.5-2 wt % of the heat-resistant additive.

5. The method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil according to claim 1, characterized in that: In the step (2), the liquid metal composite material is selected from one or more of a gallium-based alloy composite material, a bismuth-based alloy composite material, and an indium-based alloy composite material, and accounts for 0.5-2 wt % of the amount of dimethyl silicone oil used.

6. The method for preparing a heat-resistant and highly thermally conductive modified dimethyl silicone oil according to claim 1, characterized in that: In the step (2), the heat-resistant additive accounts for 0.1-2 wt % of the amount of dimethyl silicone oil used.

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