GAS PERMEATION PROPERTY OF POLYANILINE FILMS

We examined the influence of polyaniline (PAn)'s unit sequence and dop ing with low molecular weight dopants or polymer dopants on permeation property. It was found that CO2 permeability was increased by the for mation of a quinonediimine unit in PAn with the oxidation. CO2 sorptio n amount of PAn was decreased by oxidation. The increase of CO2 permea bility with oxidation, therefore, resulted from the increase of diffus ivity, which was attributable to morphological variation by the increa se of a quinonediimine unit. The permselectivity of PAn films was foun d to be remarkably improved by doping. In particular, the selectivity value of the PAn film doped with polyvinyl sulphonic acid as a polymer dopant went up to over 2,000. This remarkable increase of selectivity was found to result in the increase of selectivity, depending on diff usivity. It was also found that the permselectivity of the PAn film do ped by polymer dopants was surpassed, as compared with that doped by l ow molecular dopants. (C) 1995 John Wiley & Sons, Inc.