Dynamics of Polymer and Glass Transition in Partially Crystallized Polymer Solution Studied by Dielectric Spectroscopy

The local chain motion of poly(vinyl acetate) (PVAc) in 20 wt% PVAc benzene solution was observed by broadband dielectric spectroscopy in the frequency range of 10 mu Hz-10 GHz at various temperatures between -20 and +40 degrees C from the partially crystallized state, which is composed of a crystallized benzene phase and non-crystallized PVAc/benzene solution phase, below the melting temperature, T-m, of benzene to the liquid state above T-m. The relaxation time of the local chain motion of PVAc shows extremely strong temperature dependence below T-m. This chain motion of PVAc is the origin of the glass transition observed by differential scanning calorimetry for the partially crystallized state of the PVAc/benzene mixture below T-m. (C) Koninklijke Brill NV, Leiden, 2010