Nonlinear Resistivity in Epoxy Composites Containing ZnO Particles and Secondary Particles

Abstract

Nonlinear resistivity of epoxy polymer composites containing ZnO particles and secondary particles was investigated. Epoxy composites containing ZnO particles are known to exhibit large nonlinear resistivity. These composites are composed of amorphous shaped ZnO surface-treated with silane (s-ZnO). Epoxy composites with 20 vol% s-ZnO including various concentrations of secondary particles were prepared. The effect of the secondary particles on the nonlinear resistivity of the epoxy composites was investigated. Measurement of the average particle-to-particle distance revealed that the average distance between s-ZnO particles was shortened by the addition of t-ZnO secondary particles. The average distance between s-ZnO particles affects the electric properties of the composite, i.e., the effect of t-ZnO as secondary particle addition on the nonlinear resistivity and electric breakdown field of epoxy composites containing s-ZnO was confirmed.