Characterization of electrostrictive P(VDF-TrFE) copolymers film for high frequency and high load applications

In order to characterize the electromechanical properties of newly developed electrostrictive poly(vinylidene fluoride-trifluorethylene) copolymers for practical device applications, the following results are presented. 1), The driving field amplitude dependence of the material response. It was found that,M(S=ME2) exhibits the driving field amplitude dependence and that the apparent piezoelectric coefficient for the material under DC bias depends on both the driving field amplitude and DC field. 2). Load capability. The copolymer film has a high mechanical load capability. For example, the transverse strain remains 0.6% at 47MV/m under a tensile load of 45 MPa. The load dependence of the material response prove that the electric field induced strain in the copolymer films mainly originates from the electric field induced phase transition in the crystal regions. 3). Frequency dependence of the material response. Although the strain response decreases with increasing frequency, it is found that the strain response at 1 kHz can reach more than 80% of the response at 1Hz.