Synthesis and molecular weight dependent optical properties of mono-alkoxysubstituted polythiophenes

Poly (3-alkoxythiophene)s with moderately high molecular weights, which exh ibit good solubility and film-forming ability, were successfully synthesize d by the nickel (0) coupling reaction in good yields. The introduction of a branched side chain resulted in a molecular weight higher than that of the straight one. Broad photoluminescence (PL), ranging from 579 to 684 nm, wa s readily obtained by choosing the appropriate molecular weight sample of a mother polymer, This may provide a new method for evaluating organic lumin escent materials.