Abstract: Based on the binary system of ionic surfactant C₁₄TAB and water, the optical properties and phase behavior of them including isotropy/anisotropy, birefringence, and optical texture are studied by polarized light microscopy and visual observation. The structure and parameters of the lyotropic liquid crystal phase are characterized by small angle X-ray scattering (SAXS), and the binary phase diagram is constructed. This experiment expands the research system, reduces the experimental cost, and improves the experimental accuracy based on the original comprehensive chemistry experiment. It is helpful to understand the microstructure and properties of lyotropic liquid crystals; master the principles and methods of characterization techniques; stimulate the interests of students in physical chemistry. Further, it contributes to help students expand their scientific logic and improve their experimental skills.

Key words: Lyotropic liquid crystal, Surfactant, Birefringence, Small angle X-ray scattering