Role of the Anilinium Ion on the Selective Polymerization of Anilinium 2-Acrylamide-2-methyl-1-propanesulfonate

Alain Salvador Conejo-Dávila; Marco Armando Moya-Quevedo; David Chávez-Flores; Alejandro Vega-Rios; Erasto Armando Zaragoza-Contreras

doi:10.3390/polym13142349

Role of the Anilinium Ion on the Selective Polymerization of Anilinium 2-Acrylamide-2-methyl-1-propanesulfonate

Polymers (Basel). 2021 Jul 17;13(14):2349. doi: 10.3390/polym13142349.

Authors

Alain Salvador Conejo-Dávila¹, Marco Armando Moya-Quevedo¹, David Chávez-Flores², Alejandro Vega-Rios¹, Erasto Armando Zaragoza-Contreras¹

Affiliations

¹ Department of Engineering and Materials Chemistry, Centro de Investigación en Materiales Avanzados, S.C., Miguel de Cervantes No. 120, Complejo Industrial Chihuahua, Chihuahua C.P. 31136, Mexico.
² Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Chihuahua C.P. 31125, Mexico.

Abstract

The development of anilinium 2-acrylamide-2-methyl-1-propanesulfonate (Ani-AMPS) monomer, confirmed by ¹H NMR, ¹³C NMR, and FTIR, is systematically studied. Ani-AMPS contains two polymerizable functional groups, so it was submitted to selective polymerization either by free-radical or oxidative polymerization. Therefore, poly(anilinium 2-acrylamide-2-methyl-1-propanesulfonic) [Poly(Ani-AMPS)] and polyaniline doped with 2-acrylamide-2-methyl-1-propanesulfonic acid [PAni-AMPS] can be obtained. First, the acrylamide polymer, poly(Ani-AMPS), favored the π-stacking of the anilinium group produced by the inter- and intra-molecular interactions and was studied utilizing ¹H NMR, ¹³C NMR, FTIR, and UV-Vis-NIR. Furthermore, poly(Ani-AMPS) fluorescence shows quenching in the presence of Fe²⁺ and Fe³⁺ in the emission spectrum at 347 nm. In contrast, the typical behavior of polyaniline is observed in the cyclic voltammetry analysis for PAni-AMPS. The optical properties also show a significant change at pH 4.4. The PAni-AMPS structure was corroborated through FTIR, while the thermal properties and morphology were analyzed utilizing TGA, DSC (except PAni-AMPS), and FESEM.

Keywords: benzenaminium salts; fluorescent polymer; free-radical polymerization; oxidative polymerization; polyaniline; selective polymerization; π-stacking interactions.