Consideration of interface polarization in the modeling of dielectric property for ethylene vinyl acetate (EVA)/polyaniline conductive composites prepared through in-situ polymerization of aniline in EVA matrix

In this study conductive composite of ethylene vinyl acetate (EVA)/polyaniline (Pani) were prepared by in-situ polymerization technique. Dielectric properties (Permittivity) of the composites have been investigated with respect to concentration of Pani and frequency of electric field. For predicting permittivity of the composites, different mixing rules proposed by Lichtenecker, Bruggeman, Jaysundere–Smith, Maxwell–Wagner, and Yamada have been verified at 10, 103, and 106 Hz frequencies. It has been found that the theoretical permittivities predicted by different models differ largely from experimental permittivity when measured at 10 and 103 Hz frequencies. The limitations of the models as well as the cause of deviations between the theoretically predicted and experimentally observed results have been discussed. A new model for permittivity has been proposed by considering the generation of interface polarization between the EVA matrix and Pani particles. This model fits well with the experimentally observed results.