GAS-TRANSPORT PROPERTIES OF POLY(PHENYLENE THIOETHERIMIDE)S

Gas transport of carbon dioxide, oxygen, nitrogen and methane gases in a series of poly(phenylene thioether imide)s based on 2,2-bis(3,4-dec arboxyphenyl) hexafluoropropane dianhydride and diamine-terminated oli go(phenylene thioether)s has been investigated. The effects of the oli go(phenylene thioether) length on the gas permeabilities and diffusivi ties were determined and correlated with chain packing of the polymers . The incorporation of a long oligo(phenylene thioether) segment in th e polymer backbone decreases gas permeability and permselectivity simu ltaneously. The decreases in permeability coefficients can be related to decreases in both the diffusion coefficients and the solubility coe fficients of all the gases. Finally, the physical and gas transport pr operties are simply compared between poly(phenylene thioether imide)s and poly(phenylene thioether). (C) 1997 Elsevier Science Ltd.