Lobster-Inspired Chitosan-Derived Adhesives with a Biomimetic Design

Polysaccharide-based adhesives, especially chitosan (CS)-derived adhesives, serve as promising sustainable alternatives to traditional adhesives. However, most demonstrate a poor adhesive strength. Inspired by the inherent layered structure of marine arthropods (lobsters), a core-shell structure (SiO₂-NH₂@OPG) with amine-functionalized silica (SiO₂-NH₂) as the core and oxidized pyrogallol (OPG) as the shell is prepared in this study. The compound is blended with CS to produce a structural biomimetic wood adhesive (SiO₂-NH₂@OPG/CS) with excellent performance. In addition to thermocompressive curing, this adhesive exhibits a water-evaporation-induced curing behavior at room temperature. With reference to the design mechanism of the lobster cuticle, this microphase-separated structure consists of clustered nanofibers with varying amounts of SiO₂-NH₂@OPG particles between the fibers. This intriguing microphase structure and its mechanical effects could offer a powerful solution for improving the functional modification of wood composites.