(487f) A Theoretically Self – Consistent Netgp Approach for the Solubility of Vapors and Liquids in Glassy Polymers Based on the Perturbation of a Dry Glassy Reference State

The non-equilibrium thermodynamics of glassy polymers (NETGP) provides a formalism to calculate solubilties of volatile species in glassy polymers by way of equilibrium free energies. The classic NETGP approach of Sarti and Doghieri [Chemical Engineering Science. 1998;53(19):3435-3447] assumes the glassy polymer density of a solvent swollen polymer is known a priori. In the modified approach developed in this work, this density is calculated self-consistently the theory. The self-consistent calculation of the swollen polymer density has profound implications on both the theoretical and practical aspects of the theory. This is accomplished by means of a new class of perturbation theory, which assumes the sorption of volitile species in a glassy polymer can be treated as a perturbation to a dry polymer reference state. The new approach is then validated against sorption data in several glassy polymers.