A novel sulfonated poly（arylene ether） containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place ...A novel sulfonated poly（arylene ether） containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N＇-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton＇s reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly （MEA） prepared with the asmade film （706 EW, 100 μm dry thickness） shows better cell performance than Nation 115-MEA in the whole current density range.展开更多
A series of hydroxide conductive polymers QTBMs carrying dense aromatic side-chain quaternary ammonium groups has been synthesized by using a new monomer of 3,3＇-di（3＂,5＂-dimethylphenyl）-4,4＇-difluorodiphenyl su...A series of hydroxide conductive polymers QTBMs carrying dense aromatic side-chain quaternary ammonium groups has been synthesized by using a new monomer of 3,3＇-di（3＂,5＂-dimethylphenyl）-4,4＇-difluorodiphenyl sulfone and other commercial monomers via polycondensation reaction, and subsequent bromination, quaternization and alkalization. The chemical structures of the ionomers were confirmed by 1H- and 13C-NMR spectroscopy. Water uptake, swelling ratio, hydroxide conductivity, the number of bonded water per ammonium group （A）, volumetric ion exchange capacity （IECvwet）, mechanical and thermal properties, and chemical stability were systematically evaluated for the series of QTBMs membranes. QTBMs showed IECs ranging from 1.02 meq·g-1 to 2.11 meq·g-1; in particular, QTBM-60 membrane with the highest IEC （2.11 meq·g-1） had very high hydroxide ion conductivity of 131.9 mS·cm-1 at 80 ℃, which was attributed to the well assembled nano-channels with distinct phase separation evidenced by small-angle X-ray scattering （SAXS）. It was found that the hydrated QTBMs membranes were mechanically stable with moderate water uptakes and swelling ratios, high chemical stability under the harsh alkaline conditions. This work provides a facile way to prepare anion exchange membranes （AEMs） with high performances for the application in alkaline fuel cells.展开更多
基金This work was financially supported by the National Science Foundation of China (NSFC) (Key project, No. 29734120)the China High-Tech Development 863 Program (No. 2003AA302410)+1 种基金Natural Science Foundation of Guangdong Province (Excellent Team Project, No. 015007)Canton Province Sci & Tech Bureau (Key Strategic Project, No. A1100402) and Guangzhou Sci & Tech Bureau
文摘A novel sulfonated poly（arylene ether） containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N＇-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton＇s reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly （MEA） prepared with the asmade film （706 EW, 100 μm dry thickness） shows better cell performance than Nation 115-MEA in the whole current density range.
基金supported by the National Natural Science Foundation of China(No.51173045)Student Research Program(SRP) Funds of South China University of Technology(Nos.105612015S165 and 105612016S198)
文摘A series of hydroxide conductive polymers QTBMs carrying dense aromatic side-chain quaternary ammonium groups has been synthesized by using a new monomer of 3,3＇-di（3＂,5＂-dimethylphenyl）-4,4＇-difluorodiphenyl sulfone and other commercial monomers via polycondensation reaction, and subsequent bromination, quaternization and alkalization. The chemical structures of the ionomers were confirmed by 1H- and 13C-NMR spectroscopy. Water uptake, swelling ratio, hydroxide conductivity, the number of bonded water per ammonium group （A）, volumetric ion exchange capacity （IECvwet）, mechanical and thermal properties, and chemical stability were systematically evaluated for the series of QTBMs membranes. QTBMs showed IECs ranging from 1.02 meq·g-1 to 2.11 meq·g-1; in particular, QTBM-60 membrane with the highest IEC （2.11 meq·g-1） had very high hydroxide ion conductivity of 131.9 mS·cm-1 at 80 ℃, which was attributed to the well assembled nano-channels with distinct phase separation evidenced by small-angle X-ray scattering （SAXS）. It was found that the hydrated QTBMs membranes were mechanically stable with moderate water uptakes and swelling ratios, high chemical stability under the harsh alkaline conditions. This work provides a facile way to prepare anion exchange membranes （AEMs） with high performances for the application in alkaline fuel cells.
