(283a) The Perfluoropolymer Upper Bound

Perfluoropolymers have unique thermodynamic gas-phase partitioning properties relative to their hydrocarbon-based counterparts. For membrane-based gas separations, these properties result in perfluoropolymers having the best membrane-based separation performance for many gas pairs, including N₂/CH₄, He/H₂, He/N₂, He/CH₄, and He/CO₂. However, current polymer upper bound theory, which defines limits in permeability and selectivity for a given gas pair, does not account for these effects. In this work, solubility relationships for upper bound theory have been modified to reflect the chemical composition of the polymer. In doing so, new theoretical upper bounds have been proposed for perfluorinated polymers, and these limits are compared to data found in the literature. Our findings reveal that leveraging solubility relationships for gas-phase partitioning provides a beneficial route for surpassing current membrane performance limits. A detailed analysis of this theoretical framework and the implications related to new membrane materials design will be presented in this presentation.