Polarization-field hysteresis measurements in ferroelectric polymers

Abstract

A new method is proposed to study polarization-field hysteresis in ferroelectric polymers based on the appropriate treatment of experimentally recorded kinetics of the electret potential during the constant current corona poling The apparent conductivity and the dielectric constant measured in the same experiments are considered As an example, the P(E) dependence for PVDF is obtained and values of the coercive field and the remanent polarization are found 1

Influence of the β-phase content and degree of crystallinity on the piezo- and ferroelectric properties of poly(vinylidene fluoride)

“…Considering that dipole orientation in the crystallite is achieved through the rotation of the polymer chain segments around the chain axis at the surface of the crystallite [8,14], this effect is explained due to the hindering rotation of β-phase dipoles dispersed in a non-polar matrix mostly formed by nonferroelectric α-phase material. By stretching above 120 • C, mostly oriented α-phase crystals aligned along the stretching direction are obtained [1,4,5,28], as previously suggested by Kepler and Anderson [8].…”

Deflection model for corner-supported plates with segmented in-plane actuators

“…The strain for the opposing PVDF layer will be equal and opposite due to its opposite poling, as illustrated in Figure 2. In the above equations, we assume that the piezoelectric effects are linear, which is a valid approximation over a broad range of excitation [19]. The actuation energy is…”