Crosslinked poly(arylene ether sulfone) block copolymers containing quinoxaline crosslinkage and pendant butanesulfonic acid groups as proton exchange membranes. (21st September 2020)

• Record Type: Journal Article
• Authors: He, Fugang; Wang, Shouping; Yuan, Diao; Weng, Qiang; Chen, Pei; Chen, Xinbing; An, Zhongwei
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 46(2020)
• Page Start: 25262
• Page End: 25275
• Publication Date: 2020-09-21
• Subjects: Crosslinkable poly (arylene ether sulfone) block copolymer -- Pendant butanesulfonic acid -- Quinoxaline-based crosslinking -- Proton conductivity -- Fuel cell performance -- Microphase separation; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.06.149
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Crosslinkable poly (arylene ether sulfone) block copolymers (bSPAES (x/y)) containing pendant butanesulfonic acid and ethanedione groups were prepared from a new side-chain difluoro aromatic monomer 1-(2, 6-difluorophenyl)-2-(3, 5-dimethoxyphenyl)-1, 2-ethanedione via block copolycondensation, demethylation, and further nucleophilic substitution of 1, 4-butane sultone. Meanwhile, quinoxaline-based crosslinked block copolymers (C-bSPAES (x/y)) were obtained via cyclocondensation. The corresponding block copolymer membranes have high mechanical properties and anisotropic membrane swelling for either crosslinked or uncrosslinked ones. bSPAES (5/10) with ion exchange capacity (IEC) of 2.05 mequiv. g −1 has low water uptake ( WU ) of 59.1% at 80 °C but relatively high conductivity of 225 mS cm −1, which is ascribed to its good microphase separation. Meanwhile, the crosslinked C-bSPAES (5/10) with IEC of 1.76 mequiv. g −1 exhibits a decreased WU by half, an improved oxidative stability by 200% and a reduced membrane swelling by 40% than the uncrosslinked bSPAES (5/10). The results suggest that quinoxaline-based crosslinking can obviously improve properties of bSPAES (x/y). In addition, even though maximum power density of C-bSPAES (5/10) is lower than that of Nafion 212, C-bSPAES (5/10) still has an acceptable good single-cell performance, indicating a possible fuel cell application. Graphical abstract: Image 1 Highlights: Crosslinkable and crosslinked SPAE block copolymers are developed. DFDMED-based side-chain block ionomer membranes exhibit good microphase separation. Crosslinking contributes to enhance oxidative stability and restrain PEM swelling. Good performance is joint result of crosslinking, side-chain and block copolymer.