Application Studies of Ionic Liquid Based Microemulsions

Room temperature ionic liquids (RTILs) are being increasingly studied as environmentally benign media or catalysts for chemical reactions and new-style functional materials with promising applications in many fields, due to their unique and attractive physicochemical properties including negligible vapor pressure, nonflammability, high chemical/thermal stability, low toxicity and favorable conductivity. In recent years, great attention has been paid to ionic liquid based microemulsions due to their potential application prospects in biology, pharmaceutical, catalysis and material preparation. The recent studies in ionic liquid based microemulsions wherein ionic liquid is substituted for the oil component, for the polar or water component and for the surfactant component are reviewed in this paper. A series of influencing factors in the properties of ionic liquid based microemulsions are summarized, such as water, organic solvent, polymer, cosurfactant and temperature. The hot applications of ionic liquid based microemulsions in synthesis of nano-materials, biocatalysis, and organic reactions are also summarized. Foe enzyme in IL microemulsions, the improvement in activity is attributed to the safe environment created by IL-based reaction systems, in which enzyme molecules are entraped into aqueous microdroplets formed in W/IL microemulsions. The IL/O microemulsion systems are widely used as a medium to prepare porous or hollow nano materials.