Synthesis of fully and partially sulfonated polyanilines derived from ortanilic acid: An electrochemical and electromicrogravimetric study

• Published in: Electrochimica acta 2007-04, Vol.52 (16), p.5294-5303
• Main Authors: Cano Márquez, Abraham Guadalupe, Torres Rodríguez, Luz María, Montes Rojas, Antonio
• Format: Article
• Language: English
• Subjects: 2-Aminobenzene sulfonic acid; Charge compensation process; Chemistry; Electrochemistry; Electrodes: preparations and properties; EQCM study; Exact sciences and technology; General and physical chemistry; Other electrodes; Polyaniline; Sulfonated
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2007.02.048

The electrochemical polymerization of 2-aminobenzene sulfonic acid, also called ortanilic acid ( o-ASA), on a gold electrode precoated with polyaniline (PANI), has been carried out. We proved that the electropolymerization of o-ASA is enhanced on PANI electrodes, resulting in thicker films obtained in aqueous media at room temperature. The electrosynthesized film (P( o-ASA)) was characterized by cyclic voltammetry, FTIR and nuclear magnetic resonance. The compensation of P( o-ASA) charge was evaluated using electrochemical quartz crystal microbalance combined with cyclic voltammetry, which showed that the electroneutralization process mainly involves cations. Additionally, copolymers of aniline and o-ASA were electrosynthesized, using a metallic electrode modified with PANI also as a working electrode. The degree of sulfanation of copolymers has been modulated with the proportions of monomers in the electrosynthesis solution. The studies reveal a more important participation of cations in fully sulfonated polyaniline than in partially sulfonated polyaniline.