Temperature Dependence of the Volumetric Properties of Binary Mixtures Containing Polyethers and 1-Propanol

Abstract

Excess molar volumes (VEm) were measured at 288.15, 298.15, and 308.15 K and atmospheric pressure as a function of composition with a continuous dilution dilatometer for the binary mixtures of 1-propanol [CH3CH2CH2OH] with glymes [CH3O(CH2CH2O)mCH3, m=1,2,3, and 4]. With these results and other thermodynamic data from the literature, the following mixing quantities have been reported over the complete range of concentration or at equimolar concentration: α, volume expansivity; αE, excess volume expansivity; (∂VEm/∂T)P, and (∂HE/∂P)T at 298.15 K. The Prigogine–Flory–Patterson theory (PFP) of liquid mixtures has been applied to estimate interaction, free-volume, and internal-pressure contributions to VEm and to estimate the different mixing quantities for the mixtures. The calculated values using the PFP theory were then compared at 298.15 K with the experimentally obtained results. The PFP theory predicts excess volume VEm values rather well, while the calculated value of (∂VEm/∂T)P and (∂HE/∂P)T by using the Flory theory show general variation with the chain length of the glyme. The (∂VEm/∂T)P and (∂HE/∂P)T show deviations between theoretical and experimental values that are slightly larger in systems with lower glyme.