Аннотация:The competing reactions of substitution of polyanion of sodium polymetharylate, which is involved in water-soluble nonstoichiometric interpolyelectrolyte complex containing alkylated poly(4-vinyl pyridinium cation), with anionic surfactants (sodium caprate, sodium dodecyl sulfate) were studied by luminescence quenching technique. Equilibrium of the competing reactions was shown to be primarily controlled by the chemical nature of polycation, in particular, by the presence of hydrophobic N-alkyl substituents in polycation chain.