PIEZOELECTRIC, DIELECTRIC, AND ELASTIC PROPERTIES OF POLY(VINYLIDENE FLUORIDE TRIFLUOROETHYLENE)

The symmetry-predicted nonzero components of the piezoelectric coeffic ient, dielectric constant, and elastic compliance matrices have been d etermined on poly(vinylidene fluoride/trifluoroethylene)(75/25) copoly mer at room temperature and a frequency of 500 Hz. The temperature dep endence of each of the complex piezoelectric coefficients and complex dielectric constants has been measured in the temperature range of -10 0 to 65-degrees-C. The frequency dependence of these coefficients has also been measured at room temperature. It is found that the relaxatio n observed in the tensile piezoelectric coefficients of this material is different from that of the dielectric constants, whereas the relaxa tion of the piezoelectric shear constants shows behavior similar to th at of the dielectric constants.