Synthesis and characterization of fully disulfonated poly(arylenethioethersulfone)s containing hexafluoroisopropylidene moiety

✍ Scribed by Thuy D. Dang; Zongwu Bai; Joseph Shumaker; Narayanan Venkatasubramanian

• Book ID: 104088139
• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 535 KB
• Volume: 51
• Category: Article
• ISSN: 0032-3861
• DOI: 10.1016/j.polymer.2009.11.060

✦ Synopsis

High molecular weight sulfonated poly(arylenethioethersulfone) homopolymer containing hexafluoroisopropylidene moiety (6F-SPTES-100) was synthesized from the monomers 3, 3 0 -disulfonated-4, 4 0difluorodiphenylsulfone and 4, 4 0 -(hexafluoroisopropylidene) diphenylthiol, using 4-fluorobenzophenone as the end-capping agent in polar aprotic solvents at temperatures up to 180 C to provide the desired polymeric composition for utilization as proton exchange membrane (PEM) in fuel cells applications. Tough, ductile freestanding membranes were fabricated from N, N-dimethylacetamide (DMAc) by solventcasting. The end-capped 6F-SPTES-100 polymer was fully characterized and the membrane was found to have proton conductivity as high as 180 mS/cm which was measured at 85 C and 65% relative humidity. The proton conductivity of 6F-SPTES-100 was approximately two and half times higher than that of Nafion-117 under comparable conditions. The swelling and solubility characteristics of the 6F-SPTES-100 polymer in water are directly related to the high degree of sulfonation of the polymer backbone.