The synthesis and characterization of soluble poly(isothianaphthene) derivative: poly(5,6-dihexoxyisothianaphthene)

Poly(5,6-dihexoxyisothianaphthene) (PDHOITN) is synthesized by introducing hexoxy groups on 5 and 6 positions on the repeat unit of poly(isothianaphthene) (PITN) in order to improve its solubility and processability. The PDHOITN film has a band gap of about 0.95 eV and exhibits a high contrast and reversible color change from bluish black at the neutral state to transparent light yellow (close to colorless) at the doped state. Both the neutral and doped states of this polymer can be dissolved in common organic solvents and cast into free standing film. After doping with ferric chloride, the conductivity of the film increases 5 x 10(-5) to 2 X 10(-2) S/cm. (C) 1999 Elsevier Science Ltd. All rights reserved.