I-V characteristic and mechanism of carbon black filled epoxy resin matrix composites

Abstract

The I-V characteristic of the epoxy resin matrix composites containing conductive carbon black (CB) and sprayed CB is experimentally studied. The test results indicate that the I-V characteristic of the CB filled epoxy resin matrix composites is affected by the CB diameter. The composites containing sprayed CB with the diameter of 123nm have a linear relation between current and voltage and no variation in resistance post-exposed to an electric field. However, the composites containing conductive CB with the diameter of 33nm have a nonlinear I-V characteristic and the resistance of the composites post-exposed to an electric field decreases dramatically. A DC circuit model based on the experimental research is proposed. The occurrence of the electrical breakdown induces the nonlinear I-V characteristic and the dramatic decrease of the electrical resistance of the composites post-exposed to an electric field.