Unusual and Superfast Temperature-Triggered Actuators.

A superfast actuator based on a bilayer fibrous mat shows folding/unfolding and the formation of 3D structures in a fraction of a second. The actuation is reversible for many cycles without losing its form and size, with unfolding at room temperature and folding above 35 °C. The system is promising for making 3D bioscaffolds, electrodes, and micro-/macroactuators.