Chemical synthesis of highly electrically conductive polymers by control of oxidation potential

We report a new method for synthesizing highly electrically conducting polypyrrole and polythiophenes by control of the oxidation potential. The surface morphology and structural order of polypyrrole which was prepared by control of the oxidation potential have been investigated. A quite smooth, homogeneous and aligned fibril-like surface morphology was observed in the scanning electron micrographs of polypyrrole prepared by control of the oxidation potential, while those obtained by conventional chemical polymerization showed rough and globular structures. X- ray diffraction pattern of these two types of polypyrrole was also remarkably different. The high electrical conductivity and flexibility of polypyrrole obtained by controlling the oxidation potential may result from its homogeneous and ordered structure. The oxidation potential control technique was also applied to the polymerization of thiophene and its derivatives. Poly(3- methylthiophene)prepared by this technique exhibited electrical conductivity as high as 170 S/cm.