MOF particles are surface-functionalized to achieve an improved polymer–particle interaction in mixed matrix membranes. Compared to the neat polymer, the membranes have 3 times higher CO2 permeability with ~25% improvement in CO2/N2 selectivity.

Poly(ionic liquid)s (PILs) are an important class of technologically relevant materials. However, characterization of well-defined polyionic materials remains a challenge. Herein, we have developed a simple and versatile gel permeation chromatography (GPC) methodology for molecular weight (MW) characterization of PILs with a variety of anions. PILs with narrow MW distributions were synthesized via atom transfer radical polymerization, and the MWs obtained from GPC were further confirmed via nuclear magnetic resonance end group analysis.