Raman spectroscopic study of oxidation of aniline and N-methylaniline with dichromate

Chemical oxidative polymerization of aniline and N-methylaniline was studied with in situ time-resolved near-infrared (785 nm excitation wavelength) Raman spectroscopy. As an oxidant, dichromate anion at a molar ratio of 1:4.7 (oxidant to monomer) has been used. The results obtained have been analysed both in terms of kinetics, and changes in molecular structure. It has been shown that different features of reaction products possess different kinetic behavior. For aniline as a monomer, the relative content of reduced molecular fragments of the reaction product increases somewhat faster than that of oxidized products. For N-methylaniline, no remarkable differences have been found.