ON EQUIVALENCE OF DIELECTRIC AND MECHANICAL DISPERSIONS IN SOME POLYMERS - EG POLY(NORMAL-OCTYL METHACRYLATE)

In a comparative study of dielectric and mechanical dispersions in polymers, the usual procedure is to compare the complex dielectric constant with the complex compliance. Using this procedure one finds that the parameters used to represent these quantities are different. However, Scaife has suggested that the polarization representation is the more fundamental way to represent dielectric relaxation processes in simple polar liquids. When his recommendations were applied to the dielectric and viscoelastic data of polymers by constructing an empirical transformation procedure for the viscoelastic process, we found that, if the viscoelastic data were so treated, a significant change in the shape of the relaxation curve occurred; although the transformed dielectric and viscoelastic data had nearly the same time parameters, the equilibrium parameters proved to be quite different. However, since in that work the dispersion data were not for the same polymer specimens, some differences in the time parameters can be expected. In this paper, we consider the dielectric data of Strella and Chinai and the viscoelastic data of Child, Dannhauser and Ferry obtained for the same sample of poly(n-octyl methacrylate). In general, the time parameters are the same and the equilibrium parameters are quite different. © 1969.