Relaxer ferroelectric polymers for actuators and transducers

Ultra-high electrostrictive strains, both longitudinal and transverse strains, were observed in polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) copolymers under a proper electron irradiation treatment. In addition, in DC electric field biased states, the material also exhibits a high effective piezoelectric coefficient, comparable to those in piezoceramic PZT. The material also has a high dielectric constant and relative low dielectric loss. Moreover, these properties can be tailored in a broad range by the processing conditions. These features indicate that the material is attractive for high performance actuators and transducers. In this paper, electrostrictive strain, effective piezocoefficients, elastic, dielectric properties and polarization behavior of the material are reported. We will also show that the material exhibits typical relaxor ferroelectric behavior.