Prediction of phase equilibria in polymer systems

Abstract

A method for predicting the equilibrium of polymer-solvent and polymer-polymer systems is discussed: the Holten-Andersen Equation of State (H-A's EOS) for prediction of the thermodynamic properties of polymer and polymer mixtures with a low molecular weight solvent was applied to a wide variety of mixtures and extended to evaluate polymer compatibility. Excess volumes V E and heats of mixing, H E for binary mixtures of n-alkanes ranging from n-hexane to polyethylene were correctly predicted only using the physical properties of pure components. Lower critical solution temperatures, LCST of n-hexane, n-heptane and n-octane with polyethylene were calculated and the results were in agreement with the experimental data.