Self-aggregation behaviour of cationic surfactant tetradecyltrimethylammonium bromide and bi-amphiphilic surface active ionic liquid 3-methyl-1-pentylimidazolium dodecylsulfate in aqueous solution

Abstract

Abstract In this article, we have investigated the micellization behaviour of cationic surfactant tetradecyltrimethylammonium bromide (TTAB) and imidazolium based biamphiphilic surface active ionic liquid (BAIL), 3-methyl-1-pentylimidazolium dodecylsulfate [C5mim][DS] in aqueous solution, by employing various state of art techniques such as conductometry, tensiometry, spectrofluorometry, turbidity, dynamic light scattering (DLS), zeta potential (ζ), 1H NMR, freeze scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The conductometry, and tensiometry measurements have revealed that the micelle formation takes place at lower concentration due to strong synergistic interactions. The aggregation number (Nagg) determined from fluorescence using pyrene as a probe confirms the presence of micelle/vesicles or micelles or vesicles together at different mole fraction ratio of pure components. The various surface parameters have been evaluated by using the tensiometry. Turbidity and DLS measurements have confirmed the formation of micelles as well as vesicles over an exceptionally wide range of concentration (mole fraction = 0.1–0.9). The shape and morphology of the aggregates has been studied by using the FE-SEM and TEM measurements. The 1H NMR measurements shed light on the type of interactions prevail in the two oppositely charged mixed system.