Chromatographic studies on the properties of polypyrrole and polyaniline

This thesis describes a study of the physicochemical properties of conductive polymers. Although these polymers have been investigated extensively for more than a decade, studies of their properties employing chromatographic methods are still very limited. In this work high performance liquid chromatography was employed to investigate the properties of polypyrrole and polyaniline. Their performance as a chromatographic stationary phase was also examined. For the purpose of this study polypyrrole containing chloride and dodecylsulfate, and polyaniline with chloride, were chemically synthesized and deposited on to silica particles. The surface coating was determined by elemental analysis. Series of standard test compounds were used for chromatographic characterisation. The effect of the exposure of the polymers to redox reagents was also chromatographically examined. Both reversed-phase and anion exchange chromatographic behaviour were observed on the polymeric stationary phases. It was found that the incorporated dodecylsulfate counterions induced unique microstructure in the polypyrrole matrix, as reflected by its chromatographic behaviour toward planar molecules. The results also indicated that the interaction mechanism involved during chromatographic elution for each of the polymers investigated might be different from each other. There was indication that the polymer exposure to redox reagents changed its properties. This study indicated that it is possible for conductive polymers to b e used for chromatographic applications. The problem of low efficiency, however, should be addressed first