CHARACTERIZATION FROM XPS, FT-IR AND RAMAN SPECTROSCOPIES OF FILMS OFPOLY(P-PHENYLENE) PREPARED BY ELECTROPOLYMERIZATION OF BENZENE DISSOLVED IN KETYL PYRIDINIUM CHLORIDE ALCL3 MELTING SALT

Films of poly(p-phenylene) have been synthesized by electrochemical ox idation of benzene dissolved in ketyl pyridinium chloride-AlCl3 (1:2) melting salt. These films have been characterized from X-ray photoelec tron, Raman, photoluminescence arid FT-IR spectroscopies. A small amou nt of residual chlorine is detected from XPS experiments. The shape an d strong intensity of the extrinsic part of the photoluminescence (2.0 eV) can be related to a large amount of structural defects in the fil ms; however, the distribution of these defects is relatively homogeneo us. Raman spectra clearly show the presence of segments with small con jugation lengths in the films under consideration. Finally, FT-IR spec tra reveal that the degree of polymerization is smaller (N(dp) = 15) t han those reported (N(dp) = 30) for electrochemical oxidation of benze ne in SO2 at low temperature. These results suggest that the films obt ained by this new method present some similarities with 'Kovacic compo unds'.