To facilitate an understanding of the dielectric dynamics in the ferroelectric relaxor terpolymers, the dynamics of the normal ferroelectric copolymer [25–27] having a similar VDF/TrFE ratio was investigated initially. Fig. 6 presents dielectric spectra (measured during the heating run) for the P(VDF-TrFE) copolymer in the temperature range from−60 to 140◦C. Dielectric data acquired at temperatures from−150 to−60◦C will be presented later. In the temperature range from−150 t o140◦C,four dielectric relaxation processes can be identified. As has been pointed out earlier, the peak in the dielectric constant at 110◦C corresponds to the F-P transition. In the DSC thermo-gram, the same process is also observed as an end otherm with H=25 J/g. Reflecting its first-order phase transition nature, a large thermal hysteresis is observed and the reverse transition during cooling occurs at a temperature 50◦C lower than that measured on heating.