Glass transition temperatures and Charge Transport Characteristics of Epoxy/SiO2 Composites

Epoxy resin based composite insulation materials are widely used in power equipment, and they have also received extensive research. But the effects of the fillers on physical properties of epoxy resin has not yet formed a consistent law, and the mechanism has not been finalized. So, it is necessary to continue to study the characteristics of epoxy resin composites. In this paper, the epoxy/SiO₂ composites were studied. By comparing the effects of different nano-SiO₂ contents and the effects of the same content of micro-SiO₂ and nano-SiO₂, the results showed that the glass transition temperature, electrical conductivity and thermal stimulation current all exhibited novel trends. After the introduction of nano-silica, the glass transition temperature decreased, which indicated that the molecular chain was easier to move, and consequently the charge carriers were easier to migrate, leading a higher electrical conductivity. On the contrary, the effects of micro-SiO₂ were not obvious.