IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control   2016 年 63 卷 10 期

2016.10.01

Different thermal treatments were used to obtain various crystal structures of hydrogenated poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] films synthesized by an atom transfer radical chain transfer and controllable elimination reaction route. After analyzing the results of X-ray diffraction and differential scanning calorimeter, we found that these P(VDF-TrFE) samples possessed mixed crystal phases of ?±, ??, and ?? with various compositions depending on the TrFE content and processing temperature, and this characteristic was also demonstrated by the dielectric temperature curves. After polarizing the P(VDF-TrFE) samples at different electric fields, the effect of crystal structure on their ferroelectric and piezoelectric properties was illustrated and conformed by field emission scanning electronic microscopy morphology, which was found that large TrFE content and high temperature processing were responsible for the large remnant polarization. As a result, the annealed P(VDF-TrFE) 80/20 mol% possessed a high remnant polarization of 9.2 ??C/cm