Investigation on some thermophysical properties of poly(ethylene glycol) binary mixtures at different temperatures

Densities ρ and viscosities η for the binary mixtures of poly(ethylene glycol) + water, + 1,2-ethanediol, + 1,3-propanediol, + 1,4-butanediol over the entire concentration range were determined at temperatures (298.15 to 308.15) K with 5 K interval. The experimental data were used to calculate the excess molar volume VmE, coefficient of thermal expansion α  , excess coefficient of thermal expansion αEαE, excess Gibbs free energy of activation ΔG∗EΔG∗E, and other activation parameters (i.e.  , ΔG∗,ΔH∗,ΔS∗ΔG∗,ΔH∗,ΔS∗). The values of excess properties were fitted to Redlich–Kister polynomial equation to estimate the binary coefficients. The excess refractive index nEnE and electronic polarizability αeαe of PEG + water binary mixtures were also determined from the experimental values of refractive indices. The viscosity data were correlated with Grunberg–Nissan and Tamura–Kurata equations. Moreover, the Prigogine–Flory–Patterson theory has been used to correlate the excess molar volumes of the studied mixtures.

► Measuring densities and viscosities for binary mixtures of PEG + water or alcohols.
► Finding excess molar volume, refractive index and coefficient of thermal expansion.
► Estimating binary coefficients using Redlich–Kister polynomial equation.
► Deducing excess Gibbs free energy of activation and other activation parameters.
► Correlation of viscosity data with Grunberg–Nissan and Tamura–Kurata equations.