FACTORS INFLUENCING THE COMPETITION BETWE EN POLYMETHACRYLATE ANIONS AND ANIONIC SURFACTANTS FOR BINDING TO DODECYLPYRIDINIUM CATIONS

Using luminescence quenching and UV-VIS spectroscopy it was shown that the low-molecular-mass anionic surfactants can effectively compete wi th polymethacrylate anions for binding the cationic surfactant dodecyl pyridinium chloride. The effect of the chemical nature and the structu re of the anionic surfactant on the equilibrium in the corresponding s ubstitution reaction was studied. The ability to displace polyanion fr om its complex with the cationic surfactant changes in the a series of alkyl sulfonates: sodium bis(2-ethylhexyl)sulfosuccinate > sodium tet radecyl sulfonate > sodium decyl sulfonate > sodium octyl sulfonate. A ll other conditions being equal, the anionic surfactants bearing sulfo nate groups have higher affinity for the cationic surfactant than the carboxyl-containing surfactants and correspondingly they displace poly anions from their complexes with dodecylpyridinium chloride more easil y.