Salt effect on surface modification of silica by interpolyelectrolyte complexes

Abstract

AbstractThe effect of a low‐molecular‐mass salt on the properties of interpolyelectrolyte complexes formed as a result of interactions between poly(diallyldimethylammonium chloride) and copolymers of maleic acid with propylene or α‐methylstyrene in their salt containing non‐stoichiometric mixtures has been studied. Properties of such interpolyelectrolyte complexes were found to be determined by the chemical nature of the polyelectrolytes and by the salt concentration. The effect of salt on the surface modification of silica particles via their interactions with interpolyelectrolyte complexes has been examined. Two different ways of the surface modification of silica particles were used: (i) silica particles were contacted with previously prepared interpolyelectrolyte complexes and (ii) silica particles were contacted with cationic polyelectrolyte at first and then anionic polyelectrolyte was added. The efficiency of the surface modification was shown to be also dependent on the salt concentration and the chemical nature of polyelectrolytes. Turbidimetry, quasi‐elastic light scattering, laser microelectrophoresis, and polyelectrolyte titration were used to characterize studied systems.