Design and Study of Azobenzene‐Modified <scp>AESO</scp> Photopolymerization Coating for Information Reversible Storage Performance

ABSTRACT The photo‐induced cis‐trans isomerization of azobenzene molecules, known for their significant color changes, is extensively utilized in the functional modification of polymeric materials. However, the research on the functionalization of biomass‐based polyesters with azobenzene is limited. A key raw material for biomass‐based coatings possess reactive double bonds and excellent film‐forming capabilities, offering significant advantages for azobenzene functionalization in biomass‐based polyester applications. In this study, AESO served as the polyester matrix and acrylate azobenzene derivatives as the functional molecules. Under ultraviolet radiation, AESO underwent a carbon–carbon crosslinking reaction with the azobenzene derivatives to synthesize a novel resin. The coating of this resin on a PET substrate exhibited excellent pencil hardness (3B), adhesion (5B), and solvent resistance. By alternating exposure to ultraviolet and blue light, the coating displayed reversible switching between cis and trans isomers, enabling reversible writing and erasing of patterns. Even after 20 cycles of writing and erasing, high‐resolution patterns could still be observed (clearly visible under a 12x microscope). Furthermore, the image could be retained for up to 2 h under sunlight irradiation. This study presents a new method for functionalizing biobased polyesters.