ESR and conductivity on polypyrrole: effect of ageing

Abstract The correlation between conductivity and ESR characteristics is investigated in the case of aged polypyrrole samples. Polypyrrole powder was obtained by chemical oxidation ar 3°C with 1-naphthalen sulfonic acid as doping species and then heated to 140°C under either air or argon to accelerate the ageing process. Quantitative measurements have been carried out as a function of heating time. ESR data are discussed and compared to those of conductivity measurements obtained in the same conditions.