Electrosynthesis and characterization of o-phenylenediamine oligomers

• Published in: Polymer international 2005-03, Vol.54 (3), p.526-532
• Main Authors: Angélica del Valle, M, Díaz, Fernando R, Bodini, Mario E, Alfonso, Geraldo, Soto, Giovanny M, Borrego, Euddy D
• Format: Article
• Language: English
• Subjects: Applied sciences; dimer; Exact sciences and technology; o-phenylenediamine; oligomer electrosynthesis; oligomers; Organic polymers; Physicochemistry of polymers; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts; tetramer
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/pi.1700

The contribution of electrochemical methods to the development of conducting polymers has been most relevant, although the electropolymerization mechanism has not yet been totally elucidated. The formation of a high‐density oligomeric region in the electrode–solution interface has been clearly established as formed by oligomers with different chain lengths. It has been confirmed that, depending on the variables governing the process (applied potential, electrolysis time, concentration, etc), it is possible to control to some extent the oligomer to be generated. In this present work, the electrosynthesis of oligomers of o‐phenylenediamine is proposed. A saturated solution of the monomer was electrolysed at 0.95 V versus SCE over 1 min, using stainless steel as the working electrode material. Under these conditions, a mixture of the dimer and tetramer, relatively easy to separate by thin layer chromatography, was deposited. The products were characterized by mass spectrometry, UV–vis spectroscopy, elemental analysis and 1H NMR spectroscopy. This approach allows the synthesis of oligomers in a fast and simple way. In addition, the product is directly obtained on the electrode surface, hence making its separation and purification very straightforward. Copyright © 2004 Society of Chemical Industry