Impact of Gamma Irradiation on Surface Potential and Thermo-Mechanical Properties of Epoxy Micro-Nanocomposites

Use of epoxy based insulators in nuclear power plants and space equipment is gaining importance in recent years. Epoxy micro-nanocomposites reinforced with micro-sized silica fillers and IXEPLAS nanoparticles have been subjected to gamma irradiation of different dosages (4 kGy and 8 kGy). Surface potential decay studies reflected a marginal reduction in the initial surface potential along with increment in surface potential decay rate. Increase in carrier mobility is noticed with increment in gamma irradiation dose. From the Fourier-transform infrared spectroscopy (FTIR) studies, increased oxidation level and degradation as irradiation dosage increases was noticed compared to virgin specimen. As the irradiation dosage increases the thermal stability tends to decrease due to radiation induced degradation reactions. From dynamic mechanical analysis (DMA) results, the reduced glass transition temperature and reduced activation energy is observed in gamma irradiated specimens compared to virgin specimens.