Polarization behaviour in polymers

Dielectric polarization may be induced in polar and nonpolar electrically insulating polymers by externally applied electric fields. Such polarization may arise from dipolar orientation and injected space charges in polar and nonpolar materials respectively. Present work reports the results of a study of the nature of field induced polarization in cross-linked polyethylene (XLPE) by laser intensity modulation method (LIMM) and dielectric spectroscopy. An analysis of the data obtained by these two techniques, together with FTIR and DSC results, shows that the induced polarization may originate from a simultaneous presence of both the dipolar orientation and injected space charges.