The dielectric hysteresis behavior of polymer ferroelectrics has until now been described by an energy approach in which the redistribution of the crystal dipole orientation under an applied field is determined by the probability for the molecular dipoles to rotate about the long chain axes from one energetically stable position to the other. We propose an alternative approach in which the orientation of the dipole is determined by the equilibrium between the fieldhyphen;induced torque and the elastic restoring torque generated by the excursion of the dipoles from their initial stable positions. Measurements of hysteresis loops performed on both uniaxially and biaxially oriented films of form I poly(vinylidene fluoride) reveal that all the important features of the loops can be accounted for by our model. An added advantage of our model is that it allows for description of switching experiment where inertial effects become important.
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