Highly conjugated alternated poly(3-octylthiophene-co-thiophene)

A soluble copolymer formed by thiophene and 3-octylthiophene has been obtained by using nickel catalyst polymerization. The nearly alternated structure allows the formation of a highly conjugated system although the copolymer microstructure is not regioregular. H-1-NMR, GPC characterization and pyrolysis experiments support the alternated structure of the copolymer. Moreover, theoretical calculations indicate that the average angle between adjacent monomeric units has been reduced, in agreement with the observed shift towards lower energy of the electronic spectra of this alternated structure.