Polyaniline: The infrared spectroscopy of conducting polymer nanotubes (IUPAC Technical Report)

Abstract

Polyaniline (PANI), a conducting polymer, was prepared by the oxidation of aniline with ammonium peroxydisulfate in various aqueous media. When the polymerization was carried out in the solution of strong (sulfuric) acid, a granular morphology of PANI was obtained. In the solutions of weak (acetic or succinic) acids or in water, PANI nanotubes were produced. The oxidation of aniline under alkaline conditions yielded aniline oligomers. Fourier transform infrared (FTIR) spectra of the oxidation products differ. A group of participants from 11 institutions in different countries recorded the FTIR spectra of PANI bases prepared from the samples obtained in the solutions of strong and weak acids and in alkaline medium within the framework of an IUPAC project. The aim of the project was to identify the differences in molecular structure of PANI and aniline oligomers and to relate them to supramolecular morphology, viz. the nanotube formation. The assignment of FTIR bands of aniline oxidation products is reported.

Removal of Orange-G and Alizarin Red S from Aqueous Solution by CuCl2 Doped Polyaniline Composite Assisted by UV light

“…The strong wide peak at 1137 cm -1 corresponds to in-plane bending of the C-H band disappeared after dye adsorption. New bands observed at 1012.67 cm -1 in Orange-G and 1020.89 cm -1 in Alizarin Red S may be due to interaction of sulphonic acid group of the dyes with adsorbent material [21]. These results demonstrate physical forces are participated in the adsorption.…”

Photocatalyzed Anionic Dye Adsorption from Synthetic Wastewater by Using Polyaniline-CuCl2

“…In the present study, the experimental data was fitted into Freundlich linearized equation and the plot of ln Ce versus ln qe wasfound to be linear which From Langmuir isotherm study, the adsorption of two dyes on PANI-CuCl2 is a favourable process for the concentration range studied (figures not shown) from the calculated RL value to the C-C aromatic ring stretching of benzenoid unit. The peaks at 1302.82 and 811.68 cm -1 can be assigned to C-N stretching of the secondary aromatic amine and aromatic C-H outof-plane bending vibration, respectively [22]. FTIR spectra of the composite after the adsorption of Eosin yellowish and Congo red has showed no significant changes observed indicating that the removal of these two dyes occurred via physisorption.…”

Formation of poly-Phenylporphyrin Film Activated by Superoxide Anion Radical

“…[29][30][31][32] Интенсивная полоса 803 см -1 , обусловленная коллективными внеплоскостными коле-баниями связей С-Н в фенильном заместителе, исчезает при формировании поли-порфириновой пленки, что указывает на изменение типа замещения фенильного кольца. Полоса 3452 см -1 , относящаяся к валентным колебаниям связей N-H в фенильном заместителе, также исчезает, в то время как полосы валентных N-H колебаний тетрапиррольного цикла сохраняются.…”

“…В результате рекомбинации между порфиринами образуются мостики феназинового типа, на что указы-вает появление в спектре поли-порфириновой пленки полос с частотами около 1117, 1365, 1411 и 1454 см -1 . [31][32][33] Феназиновые фрагменты образуются при окислении гидрофеназинового мостика, показанного на Схеме 1. Изменение эффективной массы заместителя при фор-мировании пленки закономерно смещает положение деформационных колебаний тетрапиррольного цикла в область более низких частот.…”