title: Liquid crystal Janus emulsion droplets: preparation, tumbling, and swimming.
abstract: This study introduces liquid crystal (LC) Janus droplets. We describe a process for the preparation of these droplets, which consist of nematic LC and polymer compartments. The process employs solvent-induced phase separation in emulsion droplets generated by microfluidics. The droplet morphology was systematically investigated and demonstrated to be sensitive to the surfactant concentration in the background phase, the compartment volume ratio, and the possible coalescence of multiple Janus droplets. Interestingly, the combination of a polymer and an anisotropic LC introduces new functionalities into Janus droplets, and these properties lead to unusual dynamical behaviors. The different densities and solubilities of the two compartments produce gravity-induced alignment, tumbling, and directional self-propelled motion of Janus droplets. LC Janus droplets with remarkable optical properties and dynamical behaviors thus offer new avenues for applications of Janus colloids and active soft matter.
authors.affiliation: School of Natural Science, Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea. jjeong@unist.ac.kr.
authors.forename: Joonwoo
authors.initials: J
authors.lastname: Jeong
authors.forename: Adam
authors.initials: A
authors.lastname: Gross
authors.forename: Wei-Shao
authors.initials: WS
authors.lastname: Wei
authors.forename: Fuquan
authors.initials: F
authors.lastname: Tu
authors.forename: Daeyeon
authors.initials: D
authors.lastname: Lee
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Collings
authors.forename: A G
authors.initials: AG
authors.lastname: Yodh
mesh_terms: D004655:Emulsions; D057446:Hydrodynamics; D050866:Liquid Crystals / Q000737:chemistry*; D009038:Motion
chemical_list: D004655:Emulsions