Abnormal polarization enhancement effects of P(VDF-TrFE) films during fatigue process

The effects of alternating electric field on the fatigue behaviors of poly(vinylidene fluoride–trifluoroethylene) copolymer films were investigated. The value of the remanent polarization ( P r ) reached a maximum with the increase of cycle number of alternating electric filed, and then decreased as observed from the curve of polarization vs. switching cycles. It was found that the maximum point is associated with the frequency of alternating electric field. Dual effects, i.e., polarization enhancement and degradation, were supposed to coexist during the process of fatigue. A model considering the two effects was proposed to describe the fatigue behaviors, and the simulated data fit well with the experimental data. ► Abnormal polarization enhancement effects were discovered during fatigue process. ► An effective quantitative model was presented to explain the abnormal enhancement. ► Our proposed mechanism is useful to optimize properties of ferroelectric polymers.