Electrogeneration and solubilities of oxidized poly(2,5-di-(-2-thienyl)-thiophene)

Solutions of 2,5-di-(-2-thienyl)-thiophene (SSS) were studied by cyclic voltammetry, chronoamperometry and chronopotentiometry in 0.1M LiClO4+acetonitrile solution. Very reproducible weights of polymer were electrogenerated by galvanostatic experiments. Studies performed at different current densities, ranging from 0.2 to 1 mAcm(-2), and for different concentrations of SSS, ranging from 5 to 20 mM, prove the faradaic nature of the electropolymerization process. The productivity of the current was 2.7x10(-3) mg mC(-1) and 1.15 electrons were consumed to incorporate one molecule of SSS into the oxidized polymer. Density, conductivity and solubilities of the oxidized poly(SSS) in DMF, CH2Cl2, CHCl3, acetone and acetonitrile were determined. UV-vis measurements of saturated solutions in such solvents indicate that the dimer is the most important soluble component. The elemental analysis shows the presence of 0.38 ClO4- counterions and 0.20 ionic couples of Li+ClO4- per monomeric unit in the oxidized polymer.