Structure–properties relationship for the gas transport properties of new fluoro-containing aromatic polymers

Super acid catalysis offers the syntheses of a rich variety of similar but different polymer structures otherwise not easily attainable. By this synthetic method, a set of 22 polymers was prepared and their gas permeability coefficients for pure gases, with their associated ideal selectivity, were measured. An analysis of their selectivity and permeability combination protocol revealed that their membranes have combinations, specifically for the O2/N2, CO2/CH4 and CO2/N2 separations, that are in the same order of magnitude as those reported for the polysulfone and some polyimide families. For CO2/N2 separations, polymers CF3PhSO3H-T and CF3Ph-T offer membranes with CO2 permeability coefficients of 83 and 220 Barrer, with corresponding selectivity of 31 and 24. In addition, by the systematic incorporation of Me, Ph, flouro atoms or CF3 groups into their chemical structure it is possible to understand the structure/properties relationship of gas transport for this series of polymers.