Abstract :
Excess molar enthalpies, HmE, 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 HmE 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.
