Impact of organic solvents on the micellization and interfacial behavior of ionic liquid based surfactants

To elucidate the role of organic solvents, in altering the micellization and interfacial behavior of Ionic Liquid based Surfactants (ILBSs), we had investigated the effect of formamide (FA), glycerol (GLY), ethylene glycol (EG) and 1-propanol (PRO) on the micellization and interfacial behavior of 1-tetradecyl-3methylimidazolium bromide (C(14)mimBr) and 1-hexadecyl-3-methylimidazolium bromide (C(16)mimBr) ILs, in aqueous solution by conductometric and tensiometric techniques at 298.15 K. The micellization behavior has been determined by studying the changes in critical micelle concentration (cmc), degree of counter ion binding (beta), gibbs free energy of micellization (Delta G(m)(0)) and interfacial behavior by studying various surface parameters. Micellization behavior was mainly studied in light of altering the relative permittivity of the medium and displacement of water layer, which disfavors the micellization and as a result increases cmc. Effect of solvophobic parameter (S-p) and packing parameter (P) on the micellization was also examined. Results have been compared with the conventional cationic surfactants with identical alkyl chain. (C) 2016 Elsevier B.V. All rights reserved.