Temperature-Induced Liquid Crystal Microdroplet Formation in a Partially Miscible Liquid Mixture

The controlled formation of microdroplets through temperature variation is an intriguing concept for binary liquid mixtures with a critical solution temperature. Here, we investigate this phenomenon for a blend of methanol (MeOH) and a thermotropic liquid crystal (LC) 4-Cyano-4’-pentylbiphenyl (5CB). A near-room-temperatureinduced phase separation leads to nucleation, growth and coalescence of mesogen-rich droplets. The size and number of the droplets is tunable on the microscopic scale by variation of temperature quench depth and cooling rate. Further cooling induces a phase transition to nematic droplets with radial configuration, well-defined sizes and stability over the course of an hour. This fully reversible process is an interesting material system with relevance in diagnostics, optoelectronics, materials templating and extraction processes.