Nonionic Surfactant Behavior in Ionic Liquids

Ionic liquids are attracting increasing attention in many fields, including organic chemistry, electrochemistry, catalysis, physical chemistry, and engineering because of their distinctive properties. Due to their high polarity and their weak coordination ability, reactions carried out in ionic liquids may lead to enhanced reaction rates and higher yields. This research was designed to investigate the nonionic surfactant performance in ionic liquids. 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF6]) was used as the model ionic liquid and polyoxyethyleneglycol dodecyl ethers were used as nonionic surfactants. [Bmim] [PF6] surface tension was observed to drop linearly with regard to the increase of the nonionic surfactant concentration until critical micelle concentration (CMC) was reached. In addition, interaction free energy between nonionic surfactant molecules immerged in ionic liquids was found to be the driving force for the aggregation potential of nonionic surfactant molecules at CMC.