The effects of humidity on gas transport properties of sulfonated copolyimides

✍ Scribed by F. Piroux; E. Espuche; R. Mercier

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 182 KB
• Volume: 232
• Category: Article
• ISSN: 0376-7388
• DOI: 10.1016/j.memsci.2003.12.004

✦ Synopsis

Hydrogen, oxygen and carbon dioxide transport properties are studied at various hydration rates for a large series of sulfonated copolyimides synthesized with a naphthalenic dianhydride, a sulfonated diamine and various non-sulfonated diamines. For all copolymers, the gas permeability coefficient decreases when the relative humidity increases in the range 0-70% and an increase of gas flux is observed at high hydration. The magnitude of the permeability coefficient variation depends on the gas polarity and on the copolymer composition. A detailed analysis of the gas transport properties at anhydrous state and of the water sorption mechanism as a function of the copolymers composition allows to explain all the gas permeability variations as a function of hydration.