A Lignin‐Based Phenolic Resin With a Rapid Curing Rate and High Bonding Strength

ABSTRACT Inspired by the adhesive mechanism of mussel adhesive protein (DOPA), lignin was oxidized under mild conditions to mimic catechol and ortho‐quinone structures. The resulting oxidized lignin (ODL) was subsequently employed to prepare fast‐curing lignin‐based phenolic resins (ODLPF). Structural characterizations confirmed that the phenolic rings in lignin were transformed into ortho‐quinone and/or catechol following the oxidation reaction. The reactive functional groups in ODL facilitated cross‐linking reactions with the phenolic resin networks, while catechol underwent a reverse dismutation reaction with ortho‐quinone. The ODLPF resins demonstrated enhanced performance, including a faster curing rate, improved bonding strength, higher debonding work, and superior thermal stability compared to unmodified lignin‐based phenolic resins. This biomimetic modification strategy offers a sustainable approach to developing high‐performance biomass‐based phenolic resins with significant potential for industrial applications.