Dielectric behaviour of polycarbonate/poly(styrene-co-acrylonitrile) and polycarbonate/poly(methyl methacrylate) two-phase blends

Frequency and temperature dependencies of the complex permittivity epsilon* were investigated for two-phase blends polycarbonate/poly(styrene-co-acryl onitrile) (PC/SAN) and PC/poly(methyl methacrylate). The frequency dependen cies of the epsilon* at all temperatures were described by the Havriliak-Ne gami (HN) equation and the conductivity contribution. The effect of mutual miscibility on the HN shape parameters and temperature dependencies of the peak frequences fm (at which loss component epsilon " attains its maximum v alue) is discussed. The Bottcher equation is used for describing the effect of the blend composition on the reduced dielectric strength Delta epsilonT , the dipole moment mu and epsilon* values measured at the highest temperat ures (in the conductivity region). The role of Maxwell-Wagner-Sillars polar ization due to interfaces between ordered and disordered domains in PC is m entioned.