title: Aggregation behavior modulation of 1-dodecyl-3-methylimidazolium bromide by organic solvents in aqueous solution.
abstract: Material preparation in ionic liquids and environmental pollution control by ionic liquids are often closely dependent on the aggregation behavior of ionic liquids in solution. In the present work, conductivity, fluorescence probe, and dynamic light scattering techniques have been used to study the effect of organic solvents on the aggregation behavior of 1-dodecyl-3-methylimidazolium bromide in water. It was shown that the critical aggregation concentration (CAC), the ionization degree of the aggregates (α), and the standard Gibbs energy of aggregation (ΔG(m)°) of the ionic liquid increase, while its aggregation number (N(agg)) and aggregates' size decrease with increasing concentration of organic additives in water. These results have been discussed from the favorable interactions of alkyl chain of the ionic liquid with the mixed solvents. It is suggested that the solvophobic parameter, characterized quantitatively by Gibbs energy of transfer of hydrocarbon from gas into a given solvent, can be used to account for the effect of organic additives on the formation and growth of the ionic liquid aggregates in water. Aggregation behavior of ionic liquids in aqueous organic solutions can be modulated simply by the solvophobic parameters of hydrocarbon in the mixed solvents.
authors.affiliation: School of Chemical and Environmental Sciences, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Henan Normal University, Xinxiang, Henan 453007, People's Republic of China. jwang@henannu.edu.cn
authors.forename: Jianji
authors.initials: J
authors.lastname: Wang
authors.forename: Lamei
authors.initials: L
authors.lastname: Zhang
authors.forename: Huiyong
authors.initials: H
authors.lastname: Wang
authors.forename: Changzeng
authors.initials: C
authors.lastname: Wu
mesh_terms: D000433:1-Propanol / Q000737:chemistry; D000096:Acetone / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D001965:Bromides / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D019855:Ethylene Glycol / Q000737:chemistry; D005026:Ethylene Glycols / Q000737:chemistry; D005559:Formamides / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry; D000432:Methanol / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: C521425:1-dodecyl-3-methylimidazolium; D000097:Acetonitriles; D001965:Bromides; D005026:Ethylene Glycols; D005559:Formamides; D007093:Imidazoles; D052578:Ionic Liquids; D012996:Solutions; D012997:Solvents; D014867:Water; D000096:Acetone; D000431:Ethanol; C028914:triethylene glycol; D011092:Polyethylene Glycols; C031066:formamide; C013484:diethylene glycol; D000433:1-Propanol; D019855:Ethylene Glycol; D000432:Methanol; D004121:Dimethyl Sulfoxide; C032159:acetonitrile