Experimental Investigation of Interactions and Thermodynamic Properties of Poly(ethylene glycol) 200/400 + Dimethyl Adipate/Dimethyl Phthalate Binary Mixtures

Abstract

Density ρ, viscosity η, and refractive index nD have been experimentally measured for four binary mixtures dimethyl adipate + poly(ethylene glycol) 200, dimethyl adipate + poly(ethylene glycol) 400, dimethyl phthalate + poly(ethylene glycol) 200, and dimethyl phthalate + poly(ethylene glycol) 400 in the temperature range T = (288.15 to 323.15) K with a temperature step of 5 K and at atmospheric pressure. Excess molar volumes VE, viscosity deviations Δη, and deviations of refractive index ΔnD were calculated from experimental data and fitted using Redlich–Kister polynomial. Fourier-transform infrared analysis of binary mixtures and corresponding pure components was performed at 298.15 K in order to gain insight into the molecular structure of mixtures and possible intra- and intermolecular interactions. Performed IR analysis confirms an absence of intermolecular interactions between unlike compounds. Consequently, the nonideal behavior of mixtures is contributed to geometrical packing or dispersion forces ...