Thermally stimulated depolarization currents of silicone rubbers immersed in water

Effects of water immersion on electrical conductivity and permittivity as well as thermally stimulated depolarization (TSD) currents of two types of silicone rubbers are reported. The rubbers were room temperature and high temperature vulcanized and had different filler particle concentrations. The material with lower concentrations of filler particles (RTV) showed weaker sensitivity to the water immersion on the electrical properties than the highly filled material (HTV). It was also clearly visible on the variation of the TSD current spectra. By assuming a gradual formation of water layer on the filler particles the spectra were modelled and obtained agreement with the experimental results was good