Green Strategy for Improving the Formation of Reconstituted Wood-Based Composites

Abstract

In this study, a novel strategy inspired by the low melting temperature of a deep eutectic system (DES) was proposed to improve the efficient formation of reconstituted wood-based composites prepared via hot pressing. Hydrogen bond acceptors were used to prepare DES with lignin and hemicelluloses in a wood matrix in situ to achieve this goal. The feasibility and performance mechanism of this method were investigated in depth. Results show that the glass-transition point, Tg, of the amorphous components could reduce by more than 30 °C after the formation of DES. The dimensional stability and mechanical performances of the reconstituted wood-based composites were synchronously improved. The uniform bonding structure formed due to the efficient distribution of amorphous components (lignin and hemicelluloses) between the bonded interface driven by low-temperature melting of DES was an important reason for this phenomenon. In addition, the re-condensation of the degradation products of the amorphous components in wood also contributed to this. The consumption of a synthetic adhesive for wood interface bonding will be reduced in this situation. This work created a revolutionary approach for the preparation of green wood-based composites.