Recent progresses in lyotropic chromonic liquid crystal research: elasticity, viscosity, defect structures, and living liquid crystals

ABSTRACT Lyotropic chromonic liquid crystals (LCLCs) are formed by linear stacks of disc-shaped molecular in water. Combined by weak, non-covalent forces, these aggregates are reversible, flexible and polydisperse. The self-assembly nature of the basic building units gives nematic LCLCs interesting physical properties, such as very small twist constant as compared with splay and bend constants, very large splay and twist viscosities, strong temperature dependence of , , and , diverse responses to different ionic additives, and large and azimuthally asymmetric disclination cores. We discuss our experimental studies on the viscoelastic properties and the fine structure of disclinations of LCLCs and attribute their unusual properties to the fact that LCLC aggregates are not fixed in size, but vary in response to changes of temperature, concentration and ionic content in the system. We further use these properties to explain intriguing phenomena in the ‘living liquid crystals’ composed of chromonic liquid crystal and motile bacteria Bacillus Subtilis.