Improved thermal, structural and electrical properties of epoxy for use at high voltages

In this paper, the epoxy elasticity factors were investigated by thermomechanical analysis (TMA), dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA) and field emission scanning electron microscope (FESEM) to improve toughness and reduce brittleness of existing epoxy resin. Dumbbell shaped specimens were made and tested at rates of 0, 20 and 35 parts per hundred resins (phr). TMA and DMTA temperatures ranged from -20 to 200 °C and TGA ranged from 0 to 600 °C. The glass transition temperature (Tg) of elastic epoxy was measured by thermal analysis. Also investigated were the thermal expansion coefficient (α), the high-temperature characteristics, modulus and the loss factor (Tan δ). We analyzed the structure using FESEM and have found elastomer particles (elastic-factors) in the elastic epoxy matrix. We have made elastic epoxy by adding elastomer particles to existing epoxy. Generally, the toughness of elastic epoxy can be improved by changing the structure of existing epoxy of poor impact-strength. In addition, we measured the permittivity and Tan δ for investigation of the electrical properties of elastic epoxy. The permittivity and Tan δ depend on the elastomer composition. Namely, the permittivity and Tan δ increase according to the elastomer contents. For experimental analysis results, 20 phr was considered an excellent specimen.