Investigations of mixed surfactant systems of lauryl alcohol-based bissulfosuccinate anionic gemini surfactants with conventional surfactants: A fluorometric study

Abstract

In this study, fluorescence techniques have been utilized to investigate the association and aggregation properties of aqueous solutions of a pure lauryl alcohol-based bis-sulfosuccinate anionic gemini surfactant (BSGSLA1,8) with a flexible methylene (CH2)8 spacer. In addition to the fluorescence interaction behaviour of surfactant solutions of BSGSLA1,8 mixed with conventional surfactants, surfactant formulations using the anionic (sodium dodecyl sulphate (SDS)), cationic (cetyl trimethyl ammonium bromide (CTAB)) and non-ionic surfactants (Triton X-100) used in industrial applications were also studied. The aggregation number and micropolarity of the pure and mixed surfactant systems were investigated using steady-state fluorescence spectroscopy. The electrolyte effect of different concentrations of sodium chloride (NaCl) on the aggregation number and micropolarity was also explored for pure BSGSLA1,8. The best synergistic behaviour of BSGSLA1,8 was obtained with SDS compared to CTAB and Triton X-100. The maximum reduction of the pyrene intensity ratio (I1/I3) was observed with a BSGSLA1,8 and SDS mixed surfactant solution. The enhanced I1/I3 value of the mixed gemini Triton X-100 solution showed that mixed system is not as compact as pure BSGSLA1,8 surfactant micelles in the non-ionic surfactant.