Smart Wetting Control on Shape Memory Polymer Surfaces.

Control of surface wettability is very important, and can be realized by controlling surface chemistry or microstructures. Compared with surface chemistry, smart control of surface microstructure is more difficult. Recently, shape memory polymers (SMPs) have advanced to allow control of the surface microstructure and wettability, and thus, demonstrate excellent controllability and many novel functions. In this Minireview, recent achievements in wetting control on SMP surfaces with general hydrophobic, superhydrophobic, superomniphobic and superslippery properties are presented. Particular attention is paid to superhydrophobic surfaces, which display many novel functions, such as switchable isotropic/anisotropic wetting and reprogrammable gradient wetting. Furthermore, a new strategy that combines responsive molecules with the SMP microstructure is also described; this can be used to realize precise wetting control based on coordinated regulation of both surface microstructure and chemistry.