Ethaline and Glyceline binary eutectic mixtures: characteristics and intermolecular interactions

Deep eutectic solvents (DESs) are ionic liquids analogs that have been the subject of a growing interest in the scientific community. Governed by their favorable chemical and physical properties, they were utilized in a wide variety of fields. DESs possessing both desirable and undesirable properties for a specific application are not uncommon. As such, investigation into the variation of their properties upon mixing, in order to understand and improve their properties for a specific application, seems promising. In this study, the measurement of the physical and selected excess thermodynamic properties of Ethaline upon addition of Glyceline was carried out. The deviation of excess molar volume as a function of Glyceline molar fraction was observed to be alternating between negative and positive. This implies that the predominant interactions is due to either the difference in the sizes and shapes of the constituent molecules or to the effect dispersion forces. The highest deviations of the excess molar volume were observed at 30 and 90 mol% Glyceline. Density, viscosity, pH, RI and conductivity of the pure and DES mixtures were measured at different Glyceline molar fractions within the temperature range of 20 to 80 °C.