Excess molar volumes and viscosities of binary liquid mixtures of (polyether plus ester) systems at 298.15, 308.15, and 318.15 K

Excess molar volumes, V-m(E) and viscosities (eta) for the binary liquid mixtures of ((polyether + methyl) acetate (C3H6O2), ethyl acetate (C4H8O2), and propyl acetate (C5H10O2)) have been measured as a function of composition at the temperatures of 298.15, 308.15, and 318.15 K and atmospheric pressure over the full range of composition. The polyethers were 2,5,8-trioxanonane, and 2,5,8,1 1-tetraoxadodecane, From these results deviations of the viscosity, ar from a mole fraction average, and excess free energies of activation of viscous flow, DeltaG*(E) have been calculated. The results for V-m(E), Delta eta, and DeltaG*(E) are discussed in terms of the molecular interactions between the components of the mixtures. Furthermore, activation enthalpies (DeltaH*) and entropies (DeltaS*) of viscous flow have been evaluated and their variation with concentration is discussed. (C) 2001 Elsevier Science B.V. All rights reserved.