Cyclic electromechanical response of poly(vinylidene fluoride)

In this study, we present the results of cyclic electromechanical experiments conducted on uniaxially stretched poly(vinylidene fluoride) (PVDF) films. The experiments were carried out over a range of applied displacement amplitude ranging from 0.5 mm to 1.5 mm, superposed on an initial stretch on the test samples. The strains were calculated using non-contact speckle monitoring method. The hysteresis plots of mechanical and electromechanical cyclic responses are presented. Stress relaxation was observed up to 70% in orthogonal to stretch direction and 16% in the stretch direction. Observed piezoelectricity along both the directions is reported and discussed in the paper.