Within a PEM fuel cell, the polymer electrolyte membrane serves as the ion conducting medium between the anode and cathode, and as a result is a central, and often performance-limiting component of the fuel cell. The most common polymer electrolyte membrane fuel cells operate under acidic conditions and are therefore proton conducting. Nafion®, a proton exchange membrane (PEM), has dominated the field due its good processability, chemical and thermal stability, and proton conductivity (when properly hydrated). Although PEM fuel cells can perform well, they rely almost exclusively on platinum, a very expensive and scarce noble metal. A major advantage of alkaline fuel cells, relative to acidic fuel cells, is their enhanced reaction kinetics for both oxygen reduction and fuel oxidation permitting the use of less costly, non-noble metal catalysts (e.g. Ni). As a result, there is now considerable interest in hydroxide conducting polymer electrolyte membranes, also known as alkaline anion exchange membranes (AAEMs), for fuel cells operating under basic conditions.

Ionomers have been developed for use as both anion exchange membranes and ionomer interface materials. The functionalized material exhibit excellent mechanical strength and remarkable hydroxide conductivity, in addition to being solvent processable. This solvent processablity extends the potential utility of this system for use as both an AAEM and ionomer interface material from a single polymer composition.

File Number: 4957