In-situ surface liquefaction strategy for bamboo bonding with high-performance

Abstract

Conventional adhesives employed in woody composites production have drawbacks such as formaldehyde-releasing or high price, with complex production processes. In this study, we developed an in-situ surface liquefaction strategy, liquefaction and re-condensation of bamboo are directly transferred to the bonding interface. the glycerol and NaOH aqueous solution were directly coated on the bamboo surface, followed by a conventional hot-pressing process, bamboo trips were tightly bonded with a maximum bonding strength of 10.61 MPa, and the performance rivals that of phenolic resin. The bonding mechanism results revealed that glycerol initiates the ether bond cleavage of lignin on the bamboo surface and makes it from solid to flowing deformation, penetrating and filling the porous structure of the bamboo. Subsequently, the lignin condensation by the C–C bond and solidifies in these pores creating a robust cross-linked interlocking. Due to the absence of formaldehyde introduction and the elimination of the complex adhesive synthesis process, we have successfully achieved an environmentally friendly, straightforward, cost-effective, and high-performance bamboo gluing solution, making this strategy great potential for industrial production.