Can Dumbbells Make Smart Materials? Optical and Interfacial Properties of Nonspherical Janus Particles

We have developed a new approach to the synthesis of polymer colloids that produces large quantities of uniform particles with flexible control of particle geometry and surface chemistry. Specifically, we produce dumbbell shaped particles with sub-micron dimensions. The surface chemistry of each of the particles lobes can be controlled somewhat independently. Exploiting the asymmetric dielectric polarizability of these particles, we create suspensions that combine attractive properties of liquid crystals and photonic crystals. By manipulating the wetting properties of the two lobes, we create amphiphilic particles behaving as surfactants that robustly stabilize oil-water interfaces.