Densities, viscosities, and refractive indices of binary mixtures containing n-hexane + components of pine resins and essential oils

Densities, rho, viscosities, eta, and refractive indices, n(D), of binary mixtures containing n-hexane + alpha-pinene (2,6,6-trimethylbicyclo[3.1.1]hept-2-ene), + beta-pinene (6,6-dimethyl-2-methylene bicyclo[3.1.1]heptane), + p-cymene (1-methyl-4-[1-methylethyl]benzene), + (S)-(-)-limonene [(-)-1-methyl-4-(l-methylethenyl)cyclohexene], + 1,8-cineole (1,3,3-trimethyl-2-oxabicyclo[2.2.2]octane), and + linalool (3,7-dimethyl-1,6-octadien-3-ol) were determined at 298.15 K and at atmospheric pressure using a digital density meter, a Schott viscosity measuring system, and an Abbe refractometer, respectively. The excess molar volumes, V-m(E), deviations in viscosities, Deltaeta, and deviations in molar refractions, DeltaR, calculated from experimental measurements, are always negative, with the exception of the V-m(E) curve referring to the hexane + linalool mixture, which shows an inversion of sign. Results were fitted to the Redlich-Kister polynomial and qualitatively discussed in terms of molecular interactions. The McAllister multibody interaction model was used to correlate the kinematic viscosities of liquid mixtures with mole fractions.