It is still a challenge to reproduce the shape diversity and controlled re-configurability of closed surfaces and filamentous structures, which are generally found in cellular colonies and living tissues. In this work, liquid crystal (LC) droplets are self-shaped into anisotropic and three-dimensional superstructures, including LC fibres, LC helices, and differently shaped LC vesicles by mixing two surfactants with an LC dispersed phase and an aqu- eous continuous phase. The authors tune the bulk LC elasticity and interfacial energy through thermal stimuli, thus transforming an emulsion of polydispersed, spheri- cal nematic droplets into a number of uniform-diameter fibres with multiple branches. Furthermore, when the nematic LC is cooled to the smectic-A phase, the nematic fibres are broken into monodispersed microdroplets with a tunable diameter dictated by the cooling rate. The experimental findings are further supported by a theoretical model of equilibrium interface shapes. The shape transformation is induced by negative inter- facial energy, which promotes a spontaneous increase of the interfacial area at a fixed LC volume. This method is successfully applied to many different LC materials and phases, demonstrating a universal mechanism for shape transformation in complex fluids.
展开▼
