Structural aspects of piezo-electricity in the copolymer of vinylidene fluoride and tetrafluoroethylene

Abstract The piezomoduli d 31 of the copolymers of vinylidene fluoride and tetrafluoroethylene have been compared at different temperatures of uniaxial stretching. Rise in temperature leads to fall in d 31 with simultaneous increase in the intensity of the small angle meridional reflection, fall in the fraction of chains in the conformation of a flat zigzag and their disorientation. The fall noted is related to decrease in the contribution of the effect of electrostriction and change in the form of the orientation function β of the crystallites.