Use of Solvent Free-Volume Parameters from13C Relaxation to Study Polymer/Solvent Diffusion Behavior

Abstract

Variable temperature 13C nuclear magnetic resonance (NMR) spinlattice (T1) relaxation studies were carried out using pure ethylbenzene, tetrahydrofuran, and methanol samples. Single correlation times, determined from an isotropic rotational diffusion model, were correlated successfully using the free-volume equation. The solvent free-volume parameters estimated in this study were comparable with those determined from viscosity measurements. The solvent free-volume parameters estimated in this study were then used to correlate and predict diffusion behavior of polymer/solvent systems. The results were comparable with those using the parameters from viscometry when the Vrentas–Duda free-volume diffusion model was used.