Measurement of space charge distribution in hydrocarbon-based thermosetting resin with heat treatments at high temperature under high DC stress

Abstract

Recently, high performance electronic device is required insulating materials to show an excellent characteristic even at high temperature under high DC stress. In this study, we focused on insulating properties of Dicyclopentadiene (DCP) resin and Tricyclopentadiene (TCP) resin which are hydrocarbon-based thermosetting resins. These resins exhibit stable dielectric properties at high temperature [1]. Furthermore, these resins are characterized by high formability because of their low viscosity. On the other hand, polymer insulation material has a possibility of dielectric breakdown induced by accumulation of a space charge under high DC stress. Furthermore, the space charge behavior of hydrocarbon-based thermosetting resins may be affected by a heating degradation. So, we investigated the space charge accumulation behavior in a heat treated resin at high temperature under high DC stress using the PEA (Pulsed Electro-Acoustic) method, and use also evaluated the influence of high temperature on the insulating properties in the resins. Three kinds of samples with different blending ratios of DCP and TCP were used for the investigation. In this experiment, we observed the space charge distribution in untreated and heat treated samples. Furthermore, to confirm the change in the molecule structure of the heat treated sample, an IR absorption spectrum in the samples were measured using FTIR. As a result, in the samples with high TCP blending ratio, it wasn't observed any large change in space charge accumulation behavior and IR spectra based on the heat treatment. Therefore, hydrocarbon-based thermosetting resin is considered to be capable of suppressing degradation by increasing the blending ratio of TCP.