(376g) Effects of Regiochemistry on the Properties and Gas Separation Performances of Ionic Polyimides

A bis(imidazole) monomer synthesized from 6-FDA and 1-(3-aminopropyl) imidazole can be used to form "ionic polyimides" through condensation polymerizations with benzylic dihalides such as dichloroxylenes, and subsequent ion-exchange with lithium bistriflimide (LiTf₂N). Our synthetic techniques have yielded ionenes with M_N values typically > 75,000 and as high as 100,000 amu. Ionic polyimides can also absorb and incorporates ionic liquids (ILs) within their structures which can have distinct effects on ordering the ionic polyimide. This work explores how the regiochemistry of the xylene linkage (i.e., para, meta, ortho) affects polymer properties and their performances as gas separation membranes for the separation of CO₂ from species such as H₂, CH₄ and N₂.