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Ferroelectric polarization switching experiments were carried out on Form I crystal of poly(vinylidene fluoride) over a temperature range from-76°C to 125oC and at applied electric fields E up to 200 MV m-1. At 25°C, notable polarization switching currents which decayed within a few ms were observed at MVm-1 These currents became more intensive with increasing applied electric field. The maximum switching current density ]max and the maximum switching time rmax could be expressed approximately by ]max (Am-2)=0.72 (£-75) and r.;;,;x (s-1) = 37 (£-75), respectively, as also in the case with common ferroelectric crystals such as BaTi0 3 and Rochelle salts. The polarization switching behavior changed remarkably with temperature and could be separated into three parts at about-44°C and 60oC. These temperatures coincide well with the reported fJ (glass transition) and a (crystalline) relaxation temperatures, respectively. This fact indicates that the polarization switching phenomenon in poly(vinylidene fluoride) has close correlation with molecular chain motions. Finally, molecular motions responsible for the polarization switching in the three temperature regions are discussed.

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