Improving the Thermal Conductivity and Mechanical Properties of Two-component Room Temperature Vulcanized Silicone Rubber by Filling with Hydrophobically Modified SiO2-Graphene Nanohybrids

The SiO2 nanoparticles were coated on the surface of graphene oxide (GO) by sol-gel method to get the SiO2-G compound. The SiO2-G was restored and oleophylically modified to prepare hydrophobic modified SiO2-G (HM-SiO2-G) which was subsequently added to silicone rubber matrix to prepare two-component room temperature vulcanized (RTV-2) thermal conductive silicone rubber. The morphology, chemical structure and dispersity of the modified graphene were characterized with SEM, FTIR, Raman, and XPS methods. In addition, the heat-resistance behavior, mechanical properties, thermal conductivity, and electrical conductivity of the RTV-2 silicone rubber were also studied systematically. The results showed that the SiO2 nanoparticles were coated on graphene oxide successfully, and HM-SiO2-G was uniformly dispersed in RTV-2 silicone rubber. The addition of HM-SiO2-G could effectively improve the thermal stability, mechanical properties and thermal conductivity of RTV-2 silicone rubber and had no great influence on the electrical insulation performance.