Dynamics of glassy clusters appearing by nonlinear dielectric effect studies

TLDR: In this paper, preliminary results of time-resolved nonlinear dielectric effect (NDE) studies in the liquid, glass-forming epoxy resin EPON 5 are presented.

Abstract: Preliminary results of time-resolved nonlinear dielectric effect (NDE) studies in the liquid, glassforming epoxy resin EPON 5 are presented. For all tested temperatures the NDE response of the sample parametrizes the stretched exponential function with exponent $\ensuremath{\beta}=0.38\ifmmode\pm\else\textpm\fi{}0.05.$ The temperature evolution of relaxation times can be parametrized by means of the Vogel-Fulcher-Tammann function ${\ensuremath{\tau}}^{\mathrm{NDE}}={\ensuremath{\tau}}_{0}^{\mathrm{NDE}}\mathrm{exp}{(D}_{\mathrm{NDE}}{T}_{0}^{\mathrm{NDE}}/T\ensuremath{-}{T}_{0}^{\mathrm{NDE}}),$ with ${\ensuremath{\tau}}_{0}^{\mathrm{NDE}}\ensuremath{\approx}0.3\mathrm{s},$ ${D}_{E}\ensuremath{\approx}1.2,$ and ${T}_{0}^{\mathrm{NDE}}\ensuremath{\approx}261\mathrm{K}.$ The latter value is, within the limit of the experimental error, equal to the glass temperature ${T}_{g}.$ The relaxation of ``nonlinear'' changes of the dielectric permittivity induced by a strong, steady electric field may be associated with the dynamic equilibrium of glassy clusters and the surrounding fluidlike region.