Order Character and Lamellar Structure of TritonX-100/n-C10H21OH/H2O Lamellar Liquid Crystal

Order character and lamellar structure of TritonX100/nC10H21OH/H2O lamellar liquid crystal were investigated. Partial phase diagram of TritonX100/C10H21OH/H2O was measured at 25℃ by the polarizing microscope, and lamellar structure of the lamellar liquid crystal was verified by the 2H NMR spectra. The ESR spin probe method was used to detect the changes in the lamellar liquid crystal. A stearic acid, 5doxylstearic acid, was used as the spin probe. The values of hyperfine coupling constant and order parameter of lamellar liquid crystal in the phase diagram were calculated. The values of the hyperfine coupling constant with different composition were almost unchanged. It indicates that the micropolarity of the lamellar liquid crystal is very similar. The order parameter decreases with the increasing water content in lamellar liquid crystal. It can be explained by considering that: First， though the penetration is determined at the given weight ratio of C10H21OH to TritonX100, the absolute water content penetrated into the amphiphile bilayer increases with the increasing of the water content. Second， the thickness of the solvent also increases, which makes the force between layers weaker. The results also showed that order parameter of lamellar liquid crystal increased with TritonX100 content, which may be explained from the fact that the water content penetrated into the amphiphile bilayer decreases relatively and the molecules in the amphiphile bilayer are made tighten. The interlayer spacing of lamellar liquid crystal was determined by small angle Xray diffraction. The penetration ratio of water in the lamellar liquid crystal was calculated. It was about 50%.