Thermal analysis of molecular interactions in binary mixtures of propipohenone with isomeric cresols at various temperatures through thermophysical properties

Densities (rho), viscosities (eta) and speeds of sound (u) of binary mixtures of propiophenone with isomeric cresols (ortho-cresol, meta-cresol and para-cresol) including those of pure liquids, over the entire composition range, were measured at temperatures T = (303.15 K, 308.15 K and 313.15 K) and atmospheric pressure 0.1 MPa. Using these data, the excess volume and deviation in viscosity, excess isentropic compressibility, excess partial molar volumes and excess partial molar isentropic compressibilities of the components at infinite dilution were calculated. The variation of these excess properties with the composition of the mixtures suggests hydrogen bond interactions, acid-base interactions, pi-pi interactions and n-pi interactions between unlike molecules. The V-E results have been analysed in the light Prigogine-Flory-Patterson theory. An analysis of each of the three contributions, namely, interactional, free volume and characteristic pressure P* to V-E shows that free volume contribution is negative for all binary systems.