DIELECTRIC-RELAXATION STUDIES IN POLYMETHYL METHACRYLATE-MICA COMPOSITES

Dielectric properties have been studied in polymethyl methacrylate (PMMA) and composites of PMMA containing different weight ratios of mica at different temperatures and different frequencies. It has been observed that the dielectric constant (epsilon') and dielectric loss (epsilon") increase with the increasing amount of mica in the composites up to a certain percentage of mica. The activation energy values have been calculated. The results have been explained on the basis of the space charge effect, dipolar orientation and increase in the free volume of PMMA with the addition of mica in it.