Influence of triple-bonded alcohol structure on the thermo physical properties of amino-functionalized DES binary systems

The use of DESs as green solvents has been demonstrated owing to some interesting physicochemical characteristics and flexible structural compositions. In this research, the effect of structure of triple-bonded alcohol on the thermo physical properties of binary mixtures of amino-functionalized DESs, namely, tetraethyl ammonium chloride (TEAC) + 3-amino-1-propanol, was studied. Propargyl alcohol, 3-butyn-1-ol, and 2-methyl-3-butyn-2-ol were chosen as the model alkynols. Measurements of density, viscosity, and speed of sound were conducted in whole composition ranges at 303.15, 308.15, and 313.15 K. Calculation of excess molar volume, viscosity deviation, and excess isentropic compressibility values provided valuable information regarding intermolecular interactions. It was found that there was considerable deviation from ideality, demonstrating that there were significant specific interactions between the components. It has been established that the values of excess properties depend significantly on the position of the hydroxyl group and branching of the alkynol structure. The presence of negative excess molar volumes demonstrated good packing and attractive interactions in mixtures. To correlate the experimental data, the Jouyban–Acree model was successfully applied to density, speed of sound, and viscosity, yielding satisfactory agreement between experimental and calculated values.