Excess molar enthalpies of binary mixtures containing poly(ethylene glycol) 200+four cyclic ethers at (288.15, 298.15 and 313.15) K and at atmospheric pressure

Excess molar enthalpies, H_m^E, of binary mixtures containing poly(ethylene glycol) (PEG) 200+1,3-dioxolane, PEG 200+1,4-dioxane, PEG 200+oxolane and PEG 200+oxane were determined using a flow microcalorimeter at (288.15, 298.15 and 313.15) K and at atmospheric pressure. The H_m^E curves are always positive, with maxima varying from 393 J mol⁻¹ (1,3-dioxolane) to 658 J mol⁻¹ (oxolane), showing asymmetrical trends. The effect of the temperature is well marked on the calorimetric data that increase as the temperature is increased. The Redlich-Kister polynomial was used to estimate the binary fitting parameters. Root-mean-square deviations from the regression lines are reported.