Enhancing performance of sustainable biomass-based adhesive through supramolecular crosslinked networks

With the increasing depletion of petroleum resources and the significant increase in global environmental awareness, traditional petroleum-based resins have been difficult to meet the needs of industry and consumers, and the development of biomass-based adhesives has become the research focus in the field of adhesives. Here, a multiple crosslinked network-enhanced biomass-based adhesive was constructed by multiple cross-linking of aminated cellulose (AC) with citric acid (CA) and polyamide 651 (PA651). The three-layer plywood prepared with this adhesive exhibited a dry strength of 4.5 MPa with a wet strength of 3.54 MPa, which remained at 3.11 MPa after 3 h of boiling water treatment. Furthermore, the adhesive exhibited excellent adhesive performance on wood, while also demonstrated effective bonding capabilities for bamboo, steel, aluminum, copper, glass, polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), and other engineering materials. This work innovatively adopts formaldehyde-free cross-linking technology to replace the traditional formaldehyde-based cross-linking agent through the green chemical process technology route, which effectively solves the key technical problems such as insufficient water resistance and low bonding strength of biomass-based adhesives. In this work, cellulose was used as a biomass raw material to provide a new technological solution for the sustainable development of biomass adhesives in the field of industrial adhesives through a synergistic enhancement strategy of covalent/non-covalent crosslinking networks. • Bio-based wood adhesive for sustainable industrial applications was prepared. • Bonding properties were enhanced by building multiple crosslinked networks. • The adhesive can be used to bond metallic and non-metallic substrates. • This work solved the poor water resistance problem of biomass adhesive.