Humidity-responsive Janus polymer–inorganic films formed by evaporation-induced vertical segregation

Abstract

High-performance humidity-responsive actuators remain challenging to achieve. We report Janus polymer–inorganic composite films composed of poly((2-hydroxy-3-(methacryloyloxy)propyl)serine) and calcium phosphate oligomers prepared by solution casting. These films exhibit rapid, reversible bending under humidity gradients, functioning as efficient actuators due to differential water uptake and swelling across the Janus interface.