Dynamic mechanical testing of the creep and relaxation properties of polyvinylidene fluoride

The paper concerns material testing and characterizations of the time-dependent properties of polyvinylidene fluoride (PVDF), a thin film piezoelectric polymer. The study is based on the assumptions of linear viscoelastic theory of hereditary type and time-temperature equivalence principle. A developed experimental program involves quasi-static creep tests and dynamic mechanical tests. The results of this study validate the assumptions of linear viscoelasticity in application to PVDF thin films and provide consistent empirical database regarding the creep and relaxation properties of PVDF in the material directions parallel and perpendicular to the orientation of the aligned molecular chains of the polymer.