Ionic liquid induced alterations in the physicochemical properties of aqueous solutions of sodium dodecylsulfate (SDS)

Changes in the micellization behavior of an anionic surfactant sodium dodecylsulfate (SDS) in aqueous solutions have been investigated at varying concentration of hydrophobic ionic liquid 3-methy-1-pentylimidazolium hexafluorophosphate [C(5)mim][PF6] using techniques like conductometry, densiometry and speed of sound at a temperature range of 298.15-318.15 K. Critical micelle concentration (cmc) of SDS increases upon addition of [C(5)mim][PF6], which is also evidenced from fluorescence spectra of pyrene probe. Presence of solvophobic interactions is proposed to be the reason for these observations. (C) 2013 Elsevier B.V. All rights reserved.