Synthesis, physicochemical characteristics and antimicrobial studies of ethyl-substituted imidazolium-based surface active ionic liquids (SAILs)

Abstract

A series containing higher members of ethyl-substituted imidazolium-based surface active ionic liquids (SAILs) [Cneim]Br, (n = 12, 14, 16) has been synthesized by a two-step reaction pathway. They were characterized by FT-IR, 1H NMR and 13C NMR and their effect on self-aggregation behavior in aqueous solution has been examined, employing conductometric and tensiometric methods besides fluorescence measurements and UV-visible spectroscopy. The conductivity data were recorded at different temperatures and thermodynamic parameters of micelle formation such as, standard Gibbs free energy (∆Gmo), standard enthalpy (∆Hmo), standard entropy (∆Smo) were evaluated. The process of micellization is entropy driven and supported by Gibbs free energy measurements. Interfacial parameters have also been evaluated by employing surface tension technique. The SAILs were also analyzed for their antimicrobial activity by taking eleven kinds of bacterial strains.