Solubility, mutual diffusivity, specific volume and interfacial tension of molten PCL/CO2 solutions by a fully experimental procedure: effect of pressure and temperature

Abstract

Solubility, diffusivity, specific volume and interfacial tension of molten poly(ɛ-caprolactone)/CO2 solutions have been simultaneously measured by using a fully experimental technique. This technique, based on the coupling of a gravimetric measurement with the Axisymmetric Drop Shape Analysis (ADSA), provides all of the aforementioned properties in a single experiment, without relying on any theoretical assumption or equation of state at any stage of the properties evaluation. Measurements have been performed at three different temperatures (80, 90 and 100°C) and at CO2 pressures up to 4.2MPa. Dependencies of the aforementioned properties upon temperature and CO2 pressure have been highlighted. Sorption isotherms have been modeled using the Sanchez–Lacombe lattice theory, while the interfacial tension data have been interpreted by using empirical correlations.