Electrochemical characterization of soluble conducting polymers as ion exchangers

We prepared soluble conducting polymer colloids consisting of a conducting polymer (polyaniline or polypyrrole), appropriate dopant (perchlorate, benzenesulfonate, or polystyrene sulfonate), and surfactant stabilizer (poly(vinyl alcohol)). The colloid took up anionic substrates in an oxidized state and ejected them in a reduced form or in a deprotonated form, Thus, uptake and release were controlled externally by varying the redox potential or pH in solution, The exchange selectivity for inorganic substrates increased in the sequence of Cl- < Br- < BF4- < ClO4- < SCN- for the colloids doping ClO4- and benzenesulfonate. In the case of uptake of organic anions, dopant worked as a template for size recognition, and the uptake was strongly dependent on the size of the dopant. Duroquinone-polypyrrole composite was prepared to disperse the quinone in aqueous media to see if it works as a redox mediator.