New sulfonated polysulfone co-polymer membrane for low temperature fuel cells

Membranes based on a new sulfonated polysulfone co-polymer having a pending lactone cardo group in one of the structural units were characterized by ion-exchange capacity, water-up take, thermogravimetric analysis and differential scanning calorimetry. This sulfonated polysulfone co-polymer is characterized by a low glass transition temperature (138degreesC). Single cell tests in H-2/air fuel cells configuration at 30 and 60degreesC have shown for 120 mum membranes power densities of 140 and 210 mWcm(-2) respectively. A stable time performance was measured up to 250 hours.