OXIDIZED MODEL COMPOUNDS OF POLYANILINE STUDIED BY RESONANCE RAMAN-SPECTROSCOPY

The emeraldine salt structure, the only conducting form of polyaniline is not well-known. This is why, we have carried out resonance Raman s pectra (RRS) on one of these models compounds oxidized electrochemical ly in-situ in order to elucidate the electronic structure of this poly mer partially oxidized in an acidic medium. A phenyl end-capped dimer of polyaniline, N,N' diphenyl-p-phenylenediamine (named PCD), was sele cted. This dimer has been electrochemically oxidized in acetonitrile c ontaining 0,2 M tetrabutylammonium tetrafluoroborate as ground salt an d 0.1 M diphenyl phosphate as acid. The choice of laser excitation wav elength was fixed by UV-Vis absorption measurements on PCD in the acid ic medium. Numerous similarities between emeraldine salt and radical s pecies created were observed and are discussed in this paper.