Gas permeabilities of polymers with indan groups in the main chain. 1: Poly(ether ketone)s

The gas permeabilities for hydrogen, carbon dioxide, oxygen and nitrogen of a series of poly(ether ketone)s containing indan groups were determined. The effects of structural variations on permeability coefficients and selectivities for the gas pairs H-2/N-2, CO2/N-2, O-2/N-2, H-2/O-2, CO2/O-2 and H-2/CO2 are discussed. Based on the results, it is suggested that gas permeation and hence selectivity in these polymers is controlled by a specific chain segment, which consists of a sequence of flexibly linked phenyl rings. These segments are connected by the bulky and immobile indan groups. (C) 1998 Elsevier Science B.V.