Evaluation of insulation properties of epoxy resin with nano-scale silica particles

Epoxy resin containing nano-scale silica particles was prepared to evaluate partial discharge degradation and insulation breakdown strength. This material showed superior partial discharge resistance and breakdown strength to epoxy resin without silica particles. Moreover, the focus was on dimension of silica particles and a silane coupling agent to investigate the influence of epoxy/silica interface. Interface bonding by the coupling agent between the nano-scale silica particles and the epoxy resin played more important role on breakdown strength than that of micro-scale silica particles. This result was explained by simple models of nano- and micro-composites.