Study Of Effect Of Anthracene Doping On EB-PAni

Anthracene doped emeraldine base polyaniline (EB-PAni) compounds were prepared through emulsion polymerization reaction. The difference of two orders of magnitude was observed in room temperature conductivity (σ) of bare and doped EB-PAni. For bare EB-PAni σ = 1.13×10^-3 Sm^-1 and σ = 15.0×10^-5 Sm^-1 for doped EB-PAni with highest dopant concentration. UV-VIS absorption studies indicate that with increasing dopant concentration the intensity of absorption at 600 nm increases. This is attributed to the change in population of quinoid imine units in the polymer backbone. Two significant changes were observed in the FTIR spectrum of bare and doped EB-PAni. First is appearance of a peak at 1140.0 cm^-1 in doped compounds, attributed to vibration mode of the -NH⁺= structure. It suggests oxidation of polymer backbone. And second is decrease in intensity in the peak at 1294.8 cm^-1 in doped EB-PAni, which is attributed to decrease in π electron delocalization across the polymer backbone. Therefore doping of anthracene in EB-PAni was observed to bring about conversion of benzenoid amine units into quinoid imine units leading to enhancement in the population of -NH⁺= units and decrease in charge carrier mobility across its backbone.