Counter-ion induced processibility of conducting polymers: 2. Acid-assisted oxidative polymerization, doping and solubilization

A new mechanism for the polymerization, doping and solubilization of polypyrrole is presented and experimentally verified. The mechanism is based on acid-assisted oxidative polymerization, immediately followed by the oxidative doping using in both steps hydrogen peroxide as the oxidant and yielding only water as a side-product. The functionalized, deprotonated acid (e.g. camphorsulfonate) serves as a counter-ion providing solubility of the polymeric complex. Electrical conductivities of 0.1 S cm−1 are obtained for pressed pellets. The polypyrrole–camphorsulfonate complexes can be fully dissolved in organic solvents, but are unstable in solution.