Anodic oxidation of dipyrrolyls linked with conjugated spacers: study of electronic interactions between the polypyrrole chain and the spacers

In order to promote interchain electronic connections in conducting polymers, three dipyrrolyl monomers have been synthesized, with conjugated spacers mimicking chains of the oligo-phenylene, oligo-phenol and oligo-aniline type. The electrochemical behaviour of these molecules as well as the characteristics of the resulting polymers have been investigated, with the help of molecular modelling (AM1-SM2). Convergent results, obtained by cyclic voltammetry, quartz crystal microbalance and ESCA, demonstrate that both pyrrolyl moieties are involved in the polymerization process, leading therefore, to ladder-like structure polymers. FTIR studies show strong interactions between the polymer backbone and the conjugated bridges. (C) 1999 Elsevier Science S.A. All rights reserved.