Polymeric proton conducting systems based on commercial polymers: Crossover analysis and single cell testing



Continuing with the work published previously (Escribano et al., J Appl Polym Sci 2004, 93, 2394; Escribano et al., J Appl Polym Sci 2006, 102, 13) this article shows the final part of the characterization of the films object of our study, containing hydrogenated poly(butadiene-styrene) block copolymer, ethylene-propylene terpolymer, and a third component, polypropylene, polystyrene or silica, crosslinked with peroxides and heterogeneously sulfonated. Water uptake and methanol crossover were determined, and the results were compared with those of Nafion prepared by casting. A complete Membrane electrode Assembly was tested in a single cell obtaining the polarization and power curves at different temperatures and pressures, and modeling it by an electrical equivalent circuit in the symmetrical mode configuration using the electrochemical impedance spectroscopy technique. This study offers a physical interpretation relating physical parameters to several processes occurring in the system. Methanol crossover is lower than in Nafion, and power density values are in some cases higher than in Nafion. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011