Studies on the structure and electrical properties of poly(ortho-toluidine)

The conductivity of poly(ortho-toluidine) (POT), in which -CH3 groups are introduced into the benzene rings on the emeraldine chain of polyaniline (PANI), at room temperature is one or two orders of magnitude lower than that of PANI. Compared with PANI, the reasons for this reduced conductivity may be due to: (i) decrease in conjugation extent, which was supported by a blue shift of the peak position in the UV-Vis absorption spectra; (ii) decrease in extent of electron delocalization, which was proved by X-ray photoelectron spectroscopy, cyclic voltammograms and decomposition of the ESR signal; (iii) decrease in transport speed of charge carriers along and across the polymer chain, which was supported by X-ray diffraction and temperature dependence of conductivity.