Reversible recovery of nanoimprinted polymer structures.

A shape memory polymer, Nafion, has its shape memory simultaneously programmed and patterned with micro- and nanometer-scale surface textures using a nanoimprint process. Highly ordered and well-defined micro- and nanometer surface textures, for example, high aspect ratio (~5) micropillars, form the permanent shape memory of the Nafion films. When damaged, these permanently shaped micro- and nanostructures possess repair ability through a heat treatment. Reversible recoveries of the damages caused by mechanical and irradiation exposure have been demonstrated. The recovery retains above 90% of the structural fidelity, which is comparable to the shape recovery in bulk film.