Analysis of the Relaxor-Like Behavior in a Ferroelectric Copolymer P(VDF-TrFE)

The frequency dependence of real (epsilon ') and imaginary (epsilon '') components of the complex dielectric permittivity (epsilon*) of poly( vinylidene fluoride-triflouroethylene) copolymer has been determined in the temperature range from -40 to 140 degrees C including the transition to glassy state at T-g approximate to-25 degrees C and ferroelectric-to-paraelectric (F-P) transition. During the cooling, the relaxor-like behavior is observed up to T-C for enough high frequencies. Analysis of the dielectric dispersion spectra was carried out using the Havriliak-Negami empirical model. The observed peculiarities of the dielectric response are discussed on the basis of the coexistence of both the short range and long range interactions.