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A differential scanning calorimetric technique has been used to obtain solid–liquid equilibrium temperatures for the mixtures naphthalene or biphenyl + 1-tetradecanol, or + 1-hexadecanol. All the systems show a simple eutectic point, whose final composition was determined by means of the Tamman's plots using the needed values of the eutectic heat and of the heat of melting, which are also reported. DISQUAC interaction parameters for the OH/aromatic contacts in the selected systems are given. The present experimental SLE phase diagrams are similarly described by DISQUAC and UNIFAC (Dortmund) models. However, the comparison of DISQUAC and UNIFAC results for systems involving naphthalene and shorter 1-alkanols (methanol + 1-octanol) reveals that the temperature dependence of the interaction parameters is more suitable in DISQUAC. The systems are also investigated in terms of the concentration-concentration structure factor. It is shown that the positive deviations from the Raoult's law of the studied solutions become weaker when the homocoordination decreases. [ABSTRACT FROM AUTHOR]

Densities, ρ , and kinematic viscosities, ν , have been determined at atmospheric pressure and at 293.15–303.15 K for binary mixtures formed by methanol and one linear polyether of the type CH3–O–(CH2CH2O)n–CH3 (n = 2, 3, 4). Measurements on ρ and ν were carried out, respectively, using an Anton Paar DMA 602 vibrating-tube densimeter and an Ubbelohde viscosimeter. The ρ values were used to compute excess molar volumes, V m E , and, together with the ν results, dynamic viscosities (η ). Deviations from linear dependence on mole fraction for viscosity, Δ η , are also provided. Different semi-empirical equations have been employed to correlate viscosity data. Particularly, the equations used are the: Grunberg–Nissan, Hind, Frenkel, Katti–Chaudhri, McAllister and Heric. Calculations show that better results are obtained from the Hind equation. The V m E values are large and negative and contrast with the positive excess molar enthalpies, H m E , available in the literature, for these systems. This indicates that structural effects are dominant. The Δ η results are positive and correlate well with the difference in volumes of the mixture compounds, confirming the importance of structural effects. The temperature dependences of η and of the molar volume have been used to calculate enthalpies, entropies and Gibbs energies, Δ G ∗ , of viscous flow. It is demonstrated that Δ G ∗ is essentially determined by enthalpic effects. Methanol + CH3–O–(CH2CH2O)n–CH3 mixtures have been treated in the framework of the ERAS model. Results for H m E are acceptable, while the composition dependence of the V m E curves is poorly represented. This has been ascribed to the existence of strong dipolar and structural effects in the present solutions. [ABSTRACT FROM AUTHOR]