Thermodynamic and spectroscopic studies for aqueous solution of ethylene glycol monomethyl ether

As a continuation of thermodynamic study on aqueous solution of glycol ether, this paper reports new measurements of densities and viscosities for the binary liquid mixture of ethylene glycol monomethyl ether (CH3O(CH2)2OH) + water as a function of composition at T = (293.15, 303.15, 313.15, 323.15, and 333.15) K under atmospheric pressure. Density and viscosity were determined by using capillary pycnometer and Ubbelohde capillary viscometer, respectively. Surface tension was measured by drop volume method at 293.15 K. Fluorescence emission of pyrene in aqueous solution of ethylene glycol monomethyl ether was recorded in a Hitachi F-4500 spectrofluorometer at room temperature with the purpose of investigating the polarity change of solution environment. The excess molar volumes, viscosity deviations, and the excess energies of activation for viscous flow were calculated according to the experimental results. These data have been correlated by the Redlich-Kister type equations to obtain their coefficients and standard deviations. The results indicate that molecular interaction between ethylene glycol monomethyl ether and water is weaker than that between diethylene glycol monomethyl ether and water, and triethylene glycol monomethyl ether and water. Ethylene glycol monomethyl ether has marked surface activity.