Researchers developed a bio-based adhesive using camellia meal (CM) and polyethyleneimine (PEI). The CM was first oxidized to increase its reactivity, and then combined with PEI to form a dual dynamic bonds network. The resulting adhesive, OCM/PEI, exhibited strong bonding behavior to various substrates, including wood, ceramic, and steel. The adhesive’s structure was characterized using techniques such as FTIR, XPS, and XRD, which revealed the formation of imine bonds and noncovalent interactions between OCM and PEI.
The adhesive’s adhesion properties were evaluated, and it was found to have high dry and wet adhesion strength, as well as excellent stability in various harsh environments, including water, seawater, and acidic and alkaline solutions. The adhesive also showed anti-mildew and reusable properties, with the ability to reform its structure and recover its adhesion strength after damage. The researchers attributed the adhesive’s excellent performance to the synergy between the dynamic covalent and noncovalent bonds, which provided a strong and adaptable network. Overall, the OCM/PEI adhesive shows great potential for use in various applications, including woodworking, construction, and packaging.