Preparation and evaluation of sulfonated polysulfone membrane for proton exchange membrane fuel cells

Polysulfone is known as one of the most suitable polymers to use instead of commercial fluorinated membranes in proton exchange membrane fuel cells (PEMFCs). In this paper, a sulfonated polysulfone (SPSU) membrane was prepared and its physicochemical properties were investigated. To achieve this goal, at first, the polymer was sulfonated with chlorosulfonic acid in the presence of nitrogen at 50°C. The degree of sulfonation was obtained by H-NMR analysis. Sulfonated polysulfone membrane was prepared by a solution casting method using NMP as a solvent. Different properties of the prepared membrane were investigated by ion exchange capacity (IEC), water uptake (WU), and swelling ratio, and proton conductivity. The obtained results showed the prepared SPSU had appropriate properties to use as proton exchange membrane for fuel cell applications.