High-performance self-bonding bio-composites from wood fibers

Green and low-carbon bio-composites from wood fibers are in great demand in the further due to the global sustainable development. In this work, we successfully manufactured the fully bio-composites with excellent mechanical properties and improved water resistance using the dialdehyde wood fibers as the “glue” and untreated poplar wood fibers with lower particle size. The high reactive aldehyde groups provided internal chemical connection between fiber compositions and uniform size offered tightly connected structure and physical winding, which were synergistically contributed to superior performances of self-bonding bio-composites. The self-adhesive bio-composites owned outstanding flexural strength (105.2 MPa), tensile strength (35.6 MPa), internal bond strength (5.1 MPa), and hardness (0.3 GPa), better than most of the reported non-adhesive biomass materials. An innovative hydrobromic acid destruction method was used to prove the self-assembly mechanism and contributions. Both of the direct characterization and reverse destruction illustrated the covalent and hydrogen bond synergistic self-adhesive contribution of dialdehyde oxidation and homogenization. The self-bonding bio-composites have the potential to be applied to high strength outdoor household materials and structural buildings, which corresponds with the notions of carbon storage, eco-friendly, and degradation.