Effect of self-assemblies on the dynamics of phloroglucinol-based Belousov-Zhabotinsky reaction: analytical approach

The response of the phloroglucinol-BrO₃ ⁻-Ce³⁺-H₂SO₄ Belousov-Zhabotinsky (BZ) reaction to the addition of increasing amounts of some surfactants like anionic sodium dodecyl sulphate (SDS), cationic cetyltrimethylammonium bromide (CTAB), neutral TritonX-100 {4-(1,1,3,3-tetramethylbutyl) phenyl polyethylene glycol} and zwitterionic CHAPS{3[(3cholamidopropyl)dimethylammonio]-1-propanesulphonate} is monitored potentiometrically at 30 °C under stirred batch conditions. The presence of these surfactants influences the oscillatory dynamics to an extent that depends on the nature and concentration of the surfactant added. The experimental results suggest that the oscillatory behaviour of the BZ reaction in presence of surfactants owes their behaviour to the peculiar capability of organized surfactant assemblies by selectively partitioning the key species involved in the reaction and their electrostatic interaction with the charged micellar surface in case of ionic micelles. The perturbation effects in case of TritonX-100 have been ascribed to the reaction of alcoholic groups with key species involved in the reaction. For each surfactant, the evolution of oscillations has been found to be characteristic of the surfactant.