CTAB-based microemulsions with ionic liquids

The formation of microemulsions in presence of toluene, pentanol, CTAB and the ionic liquid (IL) 1-ethyl-3-methylimidazolium-ethylsulfate (EMIM-EtOSO3) or 1-ethyl-3-methylimidazolium-hexylsulfate (EMIM-HexOSO(3)) Was Studied. Due to the interface stabilizing properties of the co-surfactant pentanol the range of the isotropic microemulsion phase and microemulsion properties can be tuned by increasing the amount of co-surfactant. In addition, the microemulsion formation process can be influenced by the temperature and the counterion hydrophobicity of the ionic liquid. Therefore, bicontinuous microemulsions become available at higher temperatures. Conductometric titrations in combination to dynamic light scattering and rheological measurements show characteristic changes in the droplet size and droplet-droplet interactions by increasing the amount of the ionic liquid in the reverse IL-in-oil microemulsions. The droplet structure can be identified by means of Cryo-Scanning Electron Microscopy. (C) 2009 Elsevier B.V. All rights reserved.