Evaluation of methanol crossover in proton-conducting polyphosphazene membranes

A diffusion cell was developed to evaluate the methanol crossover for a novel class of polyphosphazene electrolyte membranes. It was found that the methanol diffusion coefficients of phenyl phosphonic acid functionalized poly[aryloxyphosphazene] membranes in an aqueous methanol solution (50% v/v) were similar to40 times lower than for Nafion 117, and similar to10-20 times lower than for sulfonated polyphosphazene membranes. (C) 2002 Elsevier Science B,V. All rights reserved.