Properties of chemically prepared polypyrrole with an aqueous solution containing Fe 2(SO 4) 3, a sulfonic surfactant and a phenol derivative

Abstract

This paper describes chemically prepared polypyrrole (PPy) with an aqueous solution containing Fe 2(SO 4) 3 as an oxidant. PPy having enhanced conductivity and environmental stability was obtained under the coexistence of a sulfonic surfactant and a phenol derivative with an electron-withdrawing group. The effect of the sulfonic surfactant was ascribed to a large-sized sulfonic anion being selectively incorporated into PPy as dopant, because an increase in the yield of PPy depended on the concentration of the surfactant. For PPy synthesized with a solution containing p-nitrophenol (pNPh), a clear increase in the doping ratio was recognized from elemental analysis. Moreover, the conductivity of PPy increased with increasing strength of the electron-withdrawing force of the substituent. The electron-withdrawing substituent of the phenol derivative seems to prevent undesirable side reactions so as to improve the regularity of the PPy backbone.