Cross-Linked Chitosan as an Eco-Friendly Binder for High-Performance Wood-Based Fiberboard

Abstract

High-performance wood-based fiberboards with high strength and dimensional stability were fabricated by hot-pressing method using 2,5-dimethoxy-2,5-dihydrofuran (DHF) cross-linked chitosan (CS) as an eco-friendly binder. The effects of cross-linked chitosan on the mechanical properties and dimensional stability of wood-based fiberboards were investigated. It is evident that cross-linked chitosan addition was effective in improving mechanical properties and dimensional stability of wood-based fiberboards. The prepared wood-based fiberboard bonded by DHF cross-linked CS displayed optimum modulus of rupture (MOR) of 42.1 MPa, modulus of elasticity (MOE) of 3986.0 MPa, internal bonding (IB) strength of 1.4 MPa, and thickness swelling (TS) value of 16.3%. The improvement of physical and mechanical properties of wood-based fiberboards could be attributed to the amide linkages and hydrogen bonds between wood fibers and cross-linked chitosan. The high-performance wood-based fiberboards fabricated in this study may be a promising candidate for eco-friendly wood-based composites.

Wood impregnation in relation to its mechanisms and properties enhancement

“…The utilization of lignin is expected to ensure efficient reactivity by providing abundant phenolic hydroxyl groups and free aromatic C3 or C5 position, as well as the ability to undergo hydroxymethylation and polymerization by condensation with formaldehyde (Rodrigues et al 2023). In addition, biological-based compounds used as impregnants have included by-products of biological activity, such as chitosan from crustacean shells (Larnøy et al 2005;Huang et al 2021), propolis extract produced by Apis mellifera (Woźniak et al 2020), and beeswax. There is also a possible variation between those compounds due to differences in species of biological organisms, source of food especially for propolis and beeswax, and extraction method.…”

Preparation and Properties of Medium-Density Fiberboards Bonded with Vanillin Crosslinked Chitosan

“…However, the poor mechanical properties of the chitosan linear structure limit the expansion of its application. In order to overcome this defect, a stable three-dimensional network structure is formed by chemical crosslinking [13,14]. JI et al [15] prepared a lignosulfonate/chitosan-based adhesive by making use of glutaraldehyde as a crosslinking agent.…”

“…Through the mechanical property test, results showed that the MDF prepared with the mass ratio of glutaraldehyde/chitosan between 0.25~0.75 met China's MDF national standard. Huang et al [14] utilized 2, 5-dimethoxy-2, 5-dihydrofuran-crosslinked CS as an environmentally-friendly binder to prepare environmentally-friendly mediumdensity fiberboard through the hot-pressing method. The results indicated that crosslinked chitosan could effectively improve the mechanical properties and dimensional stability of wood-based panels.…”