Preparation of Thin Cation‐Exchanger Films from Benzenesulfonyl Fluoride by Glow Discharge Plasma Processes

Novel ultra‐thin films of a sulfonate cation exchanger were prepared by plasma polymerization followed by hydrolysis. The use of gas mixtures of 1,3‐butadiene and benzenesulfonyl fluoride or benzenesulfonyl chloride as starting monomers was investigated. Benzenesulfonyl fluoride was found to be adequate to introduce sulfonyl halide into plasma polymers, whereas benzenesulfonyl chloride tended to be decomposed during exposure to glow discharge plasma. The influence of the level of input RF power on the properties of the resulting cation‐exchange films was also investigated. The films produced using benzenesulfonyl fluoride has a cation‐exchange capacity of 1.45 meq g−1, which is comparable to those of commercially available cation exchange membranes.