Self-adhesion lignin bonding for the production of particleboards from low-grade wood

Abstract

Classical production of construction particleboards with high-grade wood and formaldehyde-based binders induces forest depletion and pollution, calling for alternatives. Here, we designed in situ lignin bonding to transform low-grade woods into high-performance and formaldehyde-free particleboards. This method involves the deconstruction of fine wood particles to soften cell walls, eliminating undesirable water-soluble components while preserving lignin, followed by a thermo-compression molding procedure to facilitate the formation of a compact and cross-linked structure within softened wood particles. Results show that particleboard displays high mechanical strength with a rupture modulus of 66.7 MPa and excellent water resistance with a thickness swelling of 2.1%. The performance of particleboards is enhanced by low wood hardness, small particle size, removal of water-soluble fractions, and preservation of lignin. The self-adhesion technique is straightforward, practical, and scalable.