Ion-containing polymers, specifically semi-crystalline ionomers, exhibit a complex morphology stemming from the aggregation of covalently linked ionic functionality within a semi-crystalline matrix. By controlling the electrostatic interactions between ion-pairs and the conditions needed to order the crystallizable component, a wealth of technologically important properties may be developed. Recent findings from the ion-containing polymer membrane community have taught us the importance of controlled sequencing of ionic groups along polymer chains in the development of ordered polar domains for enhanced transport properties. When compared on an equal ion content basis, a blocked arrangement of ionic groups along polymer chains tends to produce more ordered nano-phase-separated domains while preserving the inherent properties of the unfunctionalized homopolymer over that of analogous random ionomers. Inspired by these demonstrated enhancements, we have begun to explore the impact of variable post-polymerization sulfonation reactions on the spatial distribution of functional groups in ionomers. Recently, we have discovered a non-functionalizing solvent for PEEK that allows for a homogeneous sulfonation reaction. Surprisingly, this new solvent also allows for the formation of a thermo-reversible gel. Following a method we previously developed to sulfonate syndiotactic polystyrene (sPS) in the gel state, we are now able to prepare a blocky form of sulfonated PEEK (SPEEK) that has a high degree of sulfonation and a high degree of crystallinity.

Morphology-Property Relationships in Ion-Containing Polymers

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.