The effect of plasticizer on the piezoelectric properties of unoriented polyvinylidene fluoride films

Abstract

Abstract The effects of the addition of small amounts (up to 3% by weight) of a low molecular weight plasticizer—tricresyl phosphate—on the piezoelectric, dielectric and dynamic mechanical response of initially unoriented poly(vinylidene fluoride) films was determined. For one set of films, the plasticizer was added after poling. Another set of films was plasticized before poling. As expected, the dynamic mechanical modulus of the films decreased while the dielectric constant of the films increased with increasing plasticizer content. The piezoelectric strain coefficient, d 31, increased for both sets of films, while the piezoelectric stress coefficient, e 31, decreased for the poled then plasticized films and increased for the plasticized then poled films.