Synthesis and electrochemical and optical characterization of poly(3-octadecylthiophene)

The 3-octadecylthiophene has been synthesized and characterized by FTIR, UV–vis and 1H and 13C NMR. The correspondent polymer, the poly(3-octadecylthiophene) (PODT) has been chemically and electrochemically synthesized. The obtained polymer is soluble in common organic solvents, such as chloroform, tetrahydrofuran and toluene. IR and NMR spectra analysis confirm its regio-regularity. The electrochemical properties studied by cyclic voltametry of PODT electrochemically synthesized were characterized by a semi-reversible behavior with one anodic peak at 0.96 V and one cathodic peak at 0.77 V vs. Ag/AgNO3. Spectroelectrochemistry and optical properties, such as optical absorption and photoluminescence (PL) were studied at different temperatures for the PODT chemically synthesized. Spectroelectrochemical results clearly indicate the polaron formation. The results obtained from the analysis of the dependence on temperature of the optical properties of the PODT casting film corroborate the high regio-regular structure of the chains.