Azobenzene Based Photo-responsive Mechanical Actuator Fabricated by Intermolecular H-bond Interaction

摘要

Photo-responsive mechanical actuator is a class of stimuli-responsive materials transferring light to mechanical energy through macroscopic transformation.To fabricate photo-responsive mechanical actuator,soft polymeric materials crosslinked with functional bridging structures are desired.Supramolecular interaction is a relatively common way to fabricate crosslinked materials due to its excellent self-assembly performance.And azobenzene and derivatives are ideal candidates of photo-responsive materials because of the unique photo-induced trans-cis isomerization.Here,a new kind of crosslinked materials based on supramolecular interaction between 4,4'-dihydroxyazobenzene and chitosan is reported.Under 355 nm irradiation,the macroscopic bending of polymeric materials occurs rapidly due to the photo-isomerization of 4,4-dihydroxyazobenzene.Meanwhile,the photo-responsive mechanical actuator can also lift weight which is up to 200 times that of the actuator itself,and convert energy from light to mechanical work efficiently.This report suggests a new kind of photo-responsive actuator based on supramolecular interaction and may be helpful to contribute a theoretical basis to the design and synthesis of photo-responsive mechanical actuator suitable for large-scale manufacturing industrialization in future.