Synthesis and characterization of poly-o-toluidine: Kinetic and structural aspects

• Autor(a) principal: De Moraes Cordeiro, Maria Angela [UNESP]
• Data de Publicação: 2005
• Outros Autores: Gonçalves, Débora, De Sousa Bulhões, Luis Otavio, Cordeiro, João Manuel Marques [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1590/S1516-14392005000100003; http://hdl.handle.net/11449/68089
• topic: Open-circuit potential; Poly-o-toluidine; Polyaniline derivatives; Polymerization mechanism; Characterization; Electrodes; Molecular structure; Polymerization; Reaction kinetics; Synthesis (chemical); Nitrogen compounds

Poly(o-methylaniline) (poly-o-toluidine, PTOL) was synthesized by chemical oxidation of o-toluidine with ammonium peroxydisulfate in an aqueous 1.0 mol L -1 HCl solution. The progress of polymerization was followed by measuring the open-circuit potential (OCP) of a Pt electrode immersed in the reaction medium with the polymerization time. The chemical synthesis of PTOL was carried out at different monomer:oxidant (M:O) molar ratios (4:1, 2:1, 1.5:1, 1:1, and 0.66:1), and the products obtained were characterized by infrared spectroscopy, gel permeation chromatography, and X-ray diffraction. The molecular weight and percentage of crystallinity of PTOL are higher for samples synthesized in an excess of the monomer, i.e. at higher M:O ratios. However, the yield of PTOL prepared at higher M:O ratios is considerably low, in particular at a 4:1 M:O ratio, which is the M:O ratio most commonly used in the literature to synthesize polyaniline and its derivatives.