Study of molecular interactions in binary mixtures of 2-ethyl-1-hexanol with primary alcohols (propan-1-ol, 2- propen-1-ol and 2- propyn-1-ol) at various temperatures

Abstract

ABSTRACT The densities (ρ), viscosities (η), and speeds of sound (u) were reported for binary mixtures of 2-ethyl-1-hexanol with aliphatic primary alcohols (propan-1-ol, 2-propen-1-ol, 2-propyn-1-ol) over the entire composition range from 303.15 K to 313.15 K and at atmospheric pressure 0.1 MPa. The excess parameters (VE,κs E), deviation in viscosity, excess partial molar volumes, ( and ) excess partial molar isentropic compressibility’s ( and ) of the components at infinite dilution were calculated from the densities, speeds of sound, and viscosities at experimental temperatures. The variation of these properties with composition of the mixtures suggests hydrogen bond and charge-transfer complex formation between 2-ethyl-1-hexanol and self-associated primary alcohols. The VE results have been analysed in the light of Prigogine-Flory-Patterson theory. An analysis of each of the three contributions, namely, interactional, free volume and P* to VE shows that interactional contribution was positive for all binary systems. The free volume effect and P* contribution were negative for all the mixtures. Furthermore, the FTIR spectra have been recorded at 298.15 K and found to be useful for understanding the presence of hydrogen bonding between dissimilar molecules in the liquid mixtures. A good agreement was obtained between excess quantities and spectroscopic data.