高绝缘室温硫化导热硅橡胶的制备及性能

Preparation and Properties of Room Temperature Vulcanized Thermal-conductive Silicone Rubber with High Electrical Insulation

以端羟基聚二甲基硅氧烷为基体硅油,Al_2O_3为基础导热填料,以二氧化硅(SiO_2)部分代替Al_2O_3,制得高绝缘室温硫化导热硅橡胶,再用纳米Al_2O_3对高绝缘室温硫化导热硅橡胶进行改性,并对其绝缘性能、导热性能、力学性能等进行测试分析。结果表明:当SiO_2、Al_2O_3的配比为60∶40、总填充量为65%时,硅橡胶的电气强度可达27.1 k V/mm。当纳米Al_2O_3填充量占粉体总量的1.5%时,硅橡胶的电气强度达到28.0 k V/mm,渗油率为0.9%,综合性能良好。

A room temperature vulcanized （RTV） thermalconductive silicone rubber was prepared by using terminal hydroxyl dimethylpolysiloxane as substrate, Al2O3 as thermal conductive filler. Then a RTV thermalconductive silicone rubber with high electrical insulation was prepared by using SiO2 instead of part of Al2O3, and the silicone rubber was modified by nano Al2O3. The insulating properties, thermal conductivity, and mechanical properties of the silicone rubber were tested and analyzed. The results show that when the ratio of SiO2 and Al2O3 is 60：40 and the total filling amount is 65%, the electric strength of the silicone rubber reaches 27.1 kV/mm. When the filling amount of nano Al2O3 is 1.5% of the total filler, the electric strength of the silicone rubber reaches 28.0 kV/mm, the oil penetration rate is 0.9%, and the comprehensive performance is good.