  The coexistence curves of the liquid-liquid equilibria (LLE) for systems of
2-phenoxyethanol (2PhEE) with heptane, octane, cyclohexane, methylcyclohexane
or ethylcyclohexane have been determined by the method of the critical
opalescence using a laser scattering technique. All the curves show an upper
critical solution temperature (UCST), have a rather horizontal top and their
symmetry depends on the relative size of the mixture compounds. UCST values are
higher for systems with linear alkanes than for solutions including cyclic
alkanes. For these mixtures, the UCST increases with the size of the alkyl
group attached to the cyclic part of the molecule. It is shown that
interactions between alkoxyethanol molecules are stronger when the hydroxyether
contains an aromatic group. Data are used to determine the critical exponent
for the order parameter mole fraction. Values obtained are consistent with
those provided by the Ising model or by the renormalization group theory.
