Physicochemical properties of switchable-hydrophilicity solvent systems: N,N-Dimethylcyclohexylamine, water and carbon dioxide

For switchable hydrophilicity solvent (SHS) systems ( N,N -Dimethylcyclohexylamine (DMCA), water, and carbon dioxide): the density, viscosity, refractive index and conductivity at (283.15–308.15) K and 0.1 Mpa, were measured. The apparent molar volumes were determined as a function of composition at each temperature from experimental data. Based on Masson’s equation limiting apparent molar volumes and Masson’s coefficient S V describing the character of interactions were calculated. The relative viscosity values were adjusted to obtain the viscosity B coefficients and dB/dT values. It has been observed that there exist strong solute-solvent and solute-solute interactions in these systems, and DMCAH-bicarbonate salt acts as structure-maker in aqueous solvent.