Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The excess volume VE, speed of sound u, and viscosity c have been measured for the binary mixtures of dipropylene glycol monobutyl ether with butylamine, dibutylamine, and tributylamine across their entire composition ranges, at a temperature of 298.15 K and atmospheric pressure. The density values derived from the excess molar volumes were converted to molar volumes, V, which are combined with the speed of sounds to obtain estimates of the product KS,m, and their excess counterparts KS,E m. The deviation of the speeds of sound uD from their ideal values uid in an ideal mixtures were calculated for all estimated values of mole fraction x1. Viscosities have also been measured for mixtures of dipropylene glycol monomethyl ether and butylamine, dibutylamine, or tributylamine at the same temperature. From the experimental data, deviations in viscosity (Alnc) and excess energies of activation for viscous flow (AG*E) have been derived for all systems. The Flory theory of mixtures provides a useful basis for a qualitative interpretation of the viscosity results. The theoretical values of molar isentropic compressibility of KS,m and of speed of sound u have been calculated using the Prigogine Flory Patterson (PFP) theory with the van der Waals (vdW) potential energy model and the results have been compared with experimental values.