Excess molar volumes and viscosity behaviour of binary mixtures of aniline/or N,N-dimethylaniline with imidazolium ionic liquids having triflate or bistriflamide anion

In this study, densities and viscosities of four binary systems {aniline/N,N-dimethylaniline + 1-butyl-3-methylimidazolium triflate ([bmim][OTf])} and {aniline/N,N-dimethylaniline + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][NTf2])} were measured at atmospheric pressure and within the temperature range T = (288.15 to 333.15) K. Excess molar volumes VE, viscosity deviations Δη and excess molar Gibbs energies of activation of viscous flow ∆G∗E were calculated and the results were fitted to a Redlich-Kister polynomial equation. Also, enthalpic and entropic parts of the ∆G∗E function were determined, at the same composition, for three studied systems that exhibit complete miscibility, since {aniline + [bmim][OTf]} is a partially miscible system. Considering the calculated thermodynamic properties, molecular interactions in the investigated binary systems were analysed and are discussed.