화학공학소재연구정보센터
Journal of Power Sources, Vol.267, 714-722, 2014
A facile synthesis of highly stable multiblock poly(arylene ether)s based alkaline membranes for fuel cells
Herein, we are disclosing simple route for the preparation of alkaline membranes (AMs) based on aminated multiblock poly(arylene ether)s (AMPEs) synthesized by nucleophilic substitution-poly condensation followed by quaternization and alkalization reactions. In this procedure, four quaternary ammonium groups are successfully introduced without use of carcinogenic reagents such as chloromethylmethyl ether (CMME). Hydrophilic/hydrophobic phase separation is responsible for their high hydroxide conductivity (similar to 150 mS cm(-1) at 80 degrees C) due to development of interconnected ion transport pathway. AMs are exhibiting good alkaline stability due to the presence of two vicinal quaternary ammonium groups and avoid degradation such as Sommelet-Hauser rearrangement and Hofmann elimination. Vicinal quaternary ammonium groups also resist nucleophilic (OH-) attack and suppress the Stevens rearrangement as well as S(N)2 substitution reaction due to stearic hindrance. Optimized AM (AMPE-M20N15 (55% DCM)) exhibits about 0.95 V open circuit voltage (OCV) and 48.8 mW cm(-2) power density at 65 degrees C in alkaline direct methanol fuel cell (ADMFC) operation. These results suggest promising begin for the preparation of stable and conductive AMs for ADMFC applications and useful for developing hydroxide conductive materials. (C) 2014 Elsevier B.V. All rights reserved.