A multifunctional lignin-based composite ultra-adhesive for wood processing

Phenolic resin adhesives are usually synthesized using phenol and formaldehyde. Both of them are fossil-based and the resins are not biodegradable. Replacing them with whole biomass-based lignin and furfural is attractive. However, it is still difficult to wholly replace them, especially lignin due to its low reactivity. In this paper, a preparation method for a composite adhesive was presented. A lignin-based composite adhesive was prepared by using a deep eutectic solvent (DES), lignin, and furfural. The lignin-based composite adhesive is a machinable adhesive for wood, and the adhesive strength for the paulownia plate reached 5.71 MPa. The adhesive also possessed outstanding flame retardance performance with a V0 grade and the ultimate oxygen index of the adhesive-coated wood was 30%. Interestingly, it also had excellent thermal insulation and photothermal performances. Importantly, wood chips can also be processed into strong regenerated wood using the adhesive. A high-strength lignin-based composite adhesive has been prepared by the reaction of lignin and furfural in a green DES, and the adhesive has excellent flame retardance, thermal insulating, and photothermal properties.

Automated summary

A preparation method for a lignin-based composite adhesive was presented in this paper. The adhesive showed excellent performance, including high adhesive strength, good flame retardance, and outstanding thermal insulation and photothermal properties. It can also be used to process wood chips into regenerated wood.