Silicone Resin-Based Composite Materials for High Thermal Stability and Thermal Conductivity

Insulated silicone/alumina (Al2O3) composites with high thermal stability and thermal conductivity were fabricated, in which the silicone resin was fabricated by a hydrolysis and condensation reaction with triethoxysilane (MTES), dimethyldiethoxysilane (DMDES) and phenyltrimethoxysilane (PhTMS). When the Al2O3 loading was 80 wt.%, the composite had only a 1.2% weight loss at 390°C. When the volume ratio of the 10 μm Al2O3 powder to 0.5 μm Al2O3 powder was controlled at 7:3, the silicone resin-based composite had thermal conductivity of 1.18 W m−1 K−1, which is 6.2 times as high as that of the pure silicone resin. Furthermore, the silicone/Al2O3 composite had dielectric strength of 87.5 kV mm−1.