Understanding Activation Volume in Glass-Forming Polymer Melts via Generalized Entropy Theory

The generalized entropy theory (GET) of glass formation provides an analytic framework for the structural relaxation time and thermodynamic properties of glass-forming polymers in terms of molecular parameters and variable thermodynamic conditions (e.g., variable pressure). Here, we utilize the GET to elucidate the physical nature of the activation volume ΔV# estimated from the leading pressure dependence of the structural relaxation time. We...