The interaction of three thermotropic liquid crystal substances (I), cholesteryl myristate, cholesteryl palmitate, or cholesteryl oleate, and various alkanes or alcohols (II) was studied by gas-liquid chromatography at various temperatures, its stationary phase being composed of 10% (w/w) of I on Chromosorb W. The logarithm of specific retention volume of II vs. reciprocal of temperature was found linear within each region of smectic, cholesteric, and isotropic liquid phases of I. From specific retention volume at various temperatures, the standard free energy, enthalpy, and entropy of the solution of II in I, Δ
soln G
Θ2, Δ
soln H
Θ2, and Δ
soln S
Θ2, were calculated. Δ
soln G
Θ2 lowered by ca. 2.5 kJ mol
-1 as II molecules became longer by one methylene group. The addition of hydroxyl group to II resulted in the lowering of Δ
soln G
Θ2 by ca. 10 kJ mol
-1. Higher values of Δ
soln H
Θ2 and Δ
soln S
Θ2 were obtained in liquid crystals than in isotropic liquid phase of I, showing an extensive destruction of liquid crystal structure of I. The difference of Δ
soln H
Θ2 and Δ
soln S
Θ2 between liquid crystal and isotropic liquid phase increased as molecules of II became longer. It was concluded that the greater solubility of longer molecules of II, as shown in lower Δ
soln G
Θ2, was mainly due to the contribution of Δ
soln S
Θ2.
抄録全体を表示