Netsu Sokutei, 32 (3), p. 133, (2005)


サーモトロピック液晶とリオトロピック液晶 - 統一的視点の可能性 -

Thermotropic and Lyotropic Liquid Crystals: Are They So Different?

Through thermodynamic analyses and considerations on the existing experimental results on cubic mesophases, the unexpected sharing of the common properties by thermotropic and lyotropic liquid crystals is demonstrated. In some thermotropic liquid crystals, the terminal alkyl chain attached to the molecular core is highly disordered as indicated by the magnitude of configurational entropy. The melt chain serves as intramolecular solvent (self-solvent), as evidenced by the close similarity between phase diagrams against chain-length and composition in binary system with n-alkane. These facts lead to the quasi-binary (QB) picture of thermotropic liquid crystals. The QB picture affords the basis to establish the structural models of cubic mesophases in classic cubic mesogens, and that to deduce the entropy difference between flat surfaces and complex surface(s) having complicated geometry such as Gyroid, a triply periodic minimal surface (TPMS).