Investigation of the Temperature Dependence of Activation Volume in Glass-Forming Polymer Melts under Variable Pressure Conditions

Motivated by empirical observations suggesting that changes in the activation volume ΔV# upon varying temperature (T), determined from the pressure (P) dependence of the segmental structural relaxation time τα, might be related to changes in the extent of collective motion in glass-forming liquids, we investigate the temperature dependence of ΔV# and the extent of collective motion in a coarse-grained polymer melt using molecular dynamics...