Novel and Inexpensive Polymer Electrolyte Membranes for Fuel Cells

Styrene was grafted onto ultrahigh molecular weight polyethylene powder (UHMWPE) by gamma irradiation using a 60Co source. Compression moulded films of selected pre-irradiated styrene-grafted ultrahigh molecular weight polyethylene (UHMWPE-g-PS) were post-sulfonated to the sulfonic acid derivative (UHMWPE-g-PSSA) for use as proton exchange membranes (PEMs). The resulting membranes were characterizes by means of various advance and relevant techniques such as Fourier Transform Infra-Red spectroscopy, Thermal Gravimetric Analysis, Differential Scanning Calorimetry, X-ray Diffraction, X-ray Photoelectron Spectroscopy, Transmission Electron Microscopy, Impedance Spectroscopy using a Solartron 1260 gain phase analyzer for proton conductivity, Nuclear Magnetic Resonance spectroscopy for determining methanol permeability, and an Instron 5565 electromechanical tester for mechanical properties. At the conclusion of experimental work, several PEM materials having a good combination of proton conductivity and low methanol permeability were selected and fabricated a Membrane Electrode Assembly (MEA) by applying it in a Direct Methanol Fuel Cell (DMFC) that ensures it has practical application.