Novel sulfonated poly(arylene ether benzimidazole) Cardo proton conducting membranes for PEMFC

作者：Ng Feifei; Jones Deborah J^*; Roziere Jacques; Bauer Bernd; Schuster Michael; Jeske Michael

来源：Journal of Membrane Science, 2010, 362(1-2): 184-191.

DOI：10.1016/j.memsci.2010.06.033

• Polybenzimidazole
• Direct sulfonation
• Reaction rate
• Electrolyte membrane
• Conductivity
• PEMFC

A novel proton conducting poly(arylene ether benzimidazole), poly[(1-(3,3'-phthalido-p-phenylene)-5-oxybenzimidazole)-benzimidazole] (PBI-OPh) has been prepared by direct sulfonation in solution. A broad study of sulfonation reaction conditions has varied the nature of the sulfonating agent (concentrated and fuming sulfuric acid), temperature and duration of the reaction The site of sulfonation along the polymer repeat unit has been identified using 2D COSY (1)H NMR. At all reaction temperatures studied, only the sites located in proximity to the ether linkages of the polymer are sulfonated using concentrated H(2)SO(4), while the use of fuming sulfuric acid allows sulfonation also of less electrophilic sites, and the preparation of samples with a degree of sulfonation of >430%. This difference in the distribution of sulfonic acid groups in samples prepared by sulfonation in concentrated and fuming sulfuric acid affects the observed water uptake properties and proton conductivity, the most highly conducting samples (25 mS cm(-1) at 25 degrees C and 100% relative humidity) being those in which percolation is favoured through substitution concomitantly at the ether-linked and Cardo segments of the polymer Sulfonated sPBI-OPh shows no weight loss below 300 degrees C in dynamic the

• 出版日期2010-10-15