title: Determination of cmc of imidazolium based surface active ionic liquids through probe-less UV-vis spectrophotometry.
abstract: In the first of its kind we herein report the results of our studies undertaken on the micellization behaviour of imidazolium based surface active ionic liquids (SAILs) to prove that their critical micelle concentration (cmc) can be estimated through ultraviolet-visible (UV-vis) spectroscopy without using any external probe. Tensiometric and spectrophotometric investigations of a series of freshly prepared SAILs viz. 1-octyl-3-methylimidazolium chloride ([OMIM][Cl]), 1-octyl-3-methylimidazolium dodecylsulphate ([OMIM][DS]), 1-octyl-3-methylimidazolium benzoate ([OMIM][Bz]), 1-octyl-3-methylimidazolium salicylate ([OMIM][Sc]), 1-octyl-3-methylimidazolium acetate ([OMIM][Ac]) are presented as a case study in support of the said claim. The cmcs estimated through spectrophotometric method were found to be close to the values estimated through tensiometry for the said SAILs. The cmcs for the investigated SAILS were found to vary in order of [OMIM][Cl]>[OMIM][Ac]>[OMIM][Bz]>[OMIM][Sc]>[OMIM][DS]. To the best of our knowledge the present communication will be the first report about the synthesis, characterization and micellization behaviour of [OMIM][Bz] and [OMIM][Sc].
authors.affiliation: Department of Chemistry, University of Kashmir, Srinagar-190006, J&K, India.
authors.forename: Mudasir Ahmad
authors.initials: MA
authors.lastname: Rather
authors.affiliation: Department of Chemistry, University of Kashmir, Srinagar-190006, J&K, India.
authors.forename: Ghulam Mohammad
authors.initials: GM
authors.lastname: Rather
authors.affiliation: Department of Chemistry, University of Kashmir, Srinagar-190006, J&K, India.
authors.forename: Sarwar Ahmad
authors.initials: SA
authors.lastname: Pandit
authors.affiliation: Department of Chemistry, University of Kashmir, Srinagar-190006, J&K, India.
authors.forename: Sajad Ahmad
authors.initials: SA
authors.lastname: Bhat
authors.affiliation: Department of Chemistry, University of Kashmir, Srinagar-190006, J&K, India. Electronic address: mohsinch@kashmiruniversity.ac.in.
authors.forename: Mohsin Ahmad
authors.initials: MA
authors.lastname: Bhat
mesh_terms: D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000032:analysis* / Q000737:chemistry*; D008823:Micelles; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013499:Surface Properties
chemical_list: C528768:1-octyl-3-methylimidazolium; D007093:Imidazoles; D052578:Ionic Liquids; D008823:Micelles
keywords: Micellization; Probe-less UV–visible spectrophotometry; Surface active ionic liquids; Tensiometry