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Updated: Jul 10, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Polymerization of aniline in the solutions of strong and weak acids: the evolution of infrared spectra and their
I Sedenková1, M Trchová, J Stejskal
1Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague 6, Czech Republic. sedenko@imc.cas.cz
Abstract:
The progress of the oxidative polymerization of aniline with ammonium peroxydisulfate in an aqueous medium has been monitored in situ by attenuated total reflection Fourier transform infrared spectroscopy. The growth of polyaniline film at the crystal surface, as well as the changes proceeding in the surrounding aqueous medium, are reflected in the spectra. The evolution of the spectra during aniline polymerization in the presence of acetic or sulfuric acid was studied with the aim of understanding the influence of acidity on the observed morphology of the final polyaniline films, granular or nanotubes. The changes occurring during polymerization are discussed with the help of differential spectra. Several processes connected with the various stages of aniline oxidation, the evolution of film morphology, or protonation, were distinguished by using factor analysis applied to a large number of spectra obtained in the course of aniline polymerizations on the crystal.
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