Water-trifluoroethanol mixtures: Some physicochemical properties

The-physicochemical properties of water-2,2,2 trifluoroethanol mixtures have been investigated, at 25 degreesC, by density, viscosity, surface tension, and relative permittivity. An analysis based on the Kirkwood theory for the dielectric polarization of mixtures has been performed and the g(K) correlation factor has been related to the occurrence of hydrogen bonding networks. Data on the above system have been analyzed and compared to data on water-ethanol mixtures, to obtain information on the role that partial fluorination plays in the interactions of alcohols with water molecules. As inferred from excess properties, nonideality contributions are smaller than in the corresponding water-ethanol solutions. Accordingly, the extension of hydrogen bond networks and/or van der Waals contributions to the overall system stability are less significant than in simple alcohols.