This thesis details approaches for the preparation of composite membranes derived from poly (vinylidene fluoride), PVDF, or copolymers thereof. It was expected that these membranes would withstand the harsh thermal oxidative conditions of a practical fuel cell and might exhibit high proton mobility. Sulfonated carbon black was used as the proton conducting component in the membrane. The advantages and the disadvantages of the materials used for fabrication of proton exchange membranes were reviewed. This thesis provides procedures for the preparation of composites of PVDF with sulfonated carbon black (CB) which might be employed as proton exchange membranes. Thin films from all compositions were prepared by compression molding or solution casting. All composites and films were thermally analyzed by differential scanning calorimetry. These studies indicated different crystallization behavior with different loadings of carbon black. Solution cast films containing PVDF, CB and Nafion® 1000 were also prepared and characterized by differential scanning calorimetry.
The electrical conductance of all solution cast films was evaluated at GM Fuel Cell Activities, Honeoye Falls, NY. Methods developed for fabrication of membranes were shown to work well. The membrane materials were however found to be electrically conductive. It is suggested that electrically conductive PVDF composites with sulfonated carbon black might have utility as electrodes. The processes and procedures employed to make the PVDF/sulfonated carbon black composites studied in this thesis might also be adapted to prepare PVDF composites with other purely proton conductive particles
