Influence of Moisture Absorption on Space Charge Behavior of Thermosetting Resin

Currently, epoxy resins are used as insulating materials for various electronic devices. However, when an epoxy resin is exposed to a high humidity environment, deterioration due to moisture absorption and ion migration occur, and it has been reported that the dielectric breakdown strength is greatly reduced. Therefore, it is important to investigate the influence of moisture absorption on insulating characteristics of the resin. In this study, space charge distribution measurement under DC stress was performed on hydrocarbon-based thermosetting resin, which is expected as a new insulating material instead of epoxy resin. We investigated how moisture absorption by humidification affects the space charge behavior in the resin. In addition, we also investigated the effect of oxidative degradation in the resin on change of moisture resistance.