Dielectric analysis of binary systems of primary diols with 1-hexanol and 1,4-dioxane at various temperatures

Experimental relative permittivity data for polar-polar and polar-nonpolar binary systems of (1,3-propanediol + 1-hexanol or 1,4-dioxane) and (1,4-butanediol + 1-hexanol or 1,4-dioxane) were obtained as a function of composition at T = (298.15, 308.15, and 318.15) K and p = 101.32 +/- 0.40 kPa. The permittivity deviations were correlated using Redlich-Kister equation for the estimation of the binary coefficients and the standard errors. For the polar-non-polar systems, the permittivity increments become more negative in the order of the mixtures containing 1HA < 1,4BD < 1,3PD. The molecular dipole moments were determined using Guggenheim-Debye method. The Kirkwood-Frohlich equation was used to evaluate the effective dipole moments of the pure and their binary mixtures. In order to obtain valuable information about intermolecular interactions, the excess parameters such as the excess permittivity and the excess Helmholtz energy were estimated. The obtained data were interpreted in terms of homo- and hetero-interactions and structure of the investigated binary mixtures. (C) 2014 Elsevier B.V. All rights reserved.