Original Articles
S. Maarouf, B. Tazi and F. Gue
Abstract
Several new composite proton conducting polymer membranes of different thicknesses (50-500mm) based on polyvinylpyrolidone (PVP), polyvinyl alcohol (PVA), sulfosuccinic acid (SSA) and phosphomolybdic acid (PMA) with or without silica have been developed for polymer electrolyte membrane fuel cells (PEMFCs). The chemical characterization of the membranes has been studied by Fourrier Transform Infrared Spectroscopy (FT-IR). The thermal stability of the membranes has been studied using the techniques of thermogravimetric analysis (TGA) and differential thermal analysis (DTA) between room temperature and 600°C.The water uptake, ionic conductivity and ionic exchange capacity of these membranes were determined. Water uptake of these membranes ranged 25 % to 93 %. The ionic conductivities of these membranes ranged between 4, 65.10-3 S/cm to 1.33.10-2 S/cm. The best water uptake and ionic conductivity were those of the membrane PVA-SSA-PVP-PMA-7.69SiO2 based on 45.25 wt% of PVA, 10.86 wt% of SSA, 18.1 wt % PVP , 18.1 wt % PMA and 7.69 wt % SiO2 and the membrane PVA-SSA-PVP- 19,61PMA containing 49.02 wt % of PVA, 11.76 wt% of SSA, 19.61 wt % PVP and 19.61 wt % of PMA. The membrane PVA-SSA-PVP-19,61PMA gave ionic conductivity of about 4, 65 10-3 S/cm in 1M NaCl media and 4, 95 10-3 S/cm in 1M H2SO4 media. The membrane PVA-SSA-PVP-PMA -7.69SiO2 gave ionic conductivity of about 8.07 10-3 S/cm in 1M NaCl media and reach 1.35 10-2 S/cm in 1M H2SO4 media. The ion exchange capacity of the PVASSA- PVP-19.61PMA and PVA-SSA-PVP-PMA7.69 SiO2 membranes were 2.92 and 3.79mmol/g respectively.