Aggregation behavior of 1-dodecyl-3-methylimidazolium bromide ionic liquid in non-aqueous solvents

In this work, aggregation behavior of [C12mim]Br in acetonitrile, ethylene glycol, N,N-dimethylformamide, formamide and dimethylsulfoxide solvents was investigated by conductivity and volume measurements. The critical aggregation concentration CAC, degree of anion binding β, and the standard Gibbs energy of aggregation ΔGo have been derived from the experimental data. Solvophobic parameters have been introduced to account for the interaction between alkyl chain of the IL and the solvents. It is shown that solvophobic effect and the hydrogen-bonding interaction between the IL anion and the solvents are the main factors affecting the aggregation of ILs in non-aqueous solvents. The aggregation of ILs in non-aqueous solvents can be controlled and regulated by solvent properties.