DIELECTRIC PROPERTIES OF INDUSTRIAL POLYMER COMPOSITE MATERIALS

Frequency and temperature dependence of dielectric constant (ε ) and dielectric loss (έ) in pure epoxy resin and polymer composites with glass fiber are studied in the frequency range 40Hz-110 MHz and in the temperature range (25-150)0C.The experimental results show that and increased with the addition of glass fiber in epoxy resin. The value of ( ε) decreased with increasing frequency which indicates that the major contribution to the polarization comes from orientation polarization .Dielectric loss peaks were also observed in the composite materials at high temperature due to Tg of epoxy .The value of ( έ) increased with increasing temperature, and is due to greater freedom of movement of the dipole molecular chains within the epoxy at high temperature.