Surface dynamics at photoactive liquid crystal polymer networks

\u3cp\u3eThe field of advanced and responsive soft materials is at the edge of a new era. After several decades during which liquid crystals generated new functions for information displays and could solve many problems in emerging fields such as (tele)communications, this material system is being utilized to reach out to completely new application fields with functions that can take over biological actions (cell growth and manipulation), change the way materials, machines, or robots interact with humans (haptics), and modulate surface properties, e.g., tribology and wettability. This Progress Report concentrates on creating surface movement in liquid crystal networks with an emphasis on the light-responsive dynamic surface topographies that transfer from a flat to a predesigned corrugated state via light illumination, e.g., UV and visible light. Within this framework, the interaction between dynamic surfaces and the environment, such as controlled friction, wettability, and material transport, are illustrated. In addition, the light-induced thermal effect is discussed. The article concludes with the existing challenges and an outlook on the opportunities.\u3c/p\u3