Shape Memory Behaviors of Micro- and Nano-Particles

The behaviors of shape memory polymers to be programmed into temporary shapes and recovery their original geometries have been well investigated at the macro-scale. Here, we examine the shape memory behaviors of micro- and nano-particles. The programming of these particles with nanoimprint lithography and the recovery of these particles were systematically investigated. Particularly, the overall shape memory effect is influenced by the substrate-particle adhesion, mechanical constraints of the metal capping layer, particle sizes, and programing conditions. By controlling these factors, particles (including Janus particles) with systematically varying morphology and properties can be achieved.