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The processing of natural wood into a high‐performance wood‐based composite to broaden the potential applications of wood can be achieved by various techniques using bulk wood as a raw material. However, attention has seldom been paid to the use of wood veneers for preparing high‐performance structural materials. In this study, delignified birch veneers are used as raw materials to fabricate high‐strength delignified wood‐based laminated composites (DWLCs) with phenol‐formaldehyde (PF) resin as adhesive. The DWLCs with a PF resin content of 40% had high mechanical properties and displayed flexural and tensile stress of 405.8 and 324.4 MPa, respectively. The flexural and tensile stress are 1.24 and 1.21 times higher than those of natural wood‐based laminated composites (WLCs). And we confirmed that partial delignification could contribute to enhancing the mechanical properties of high‐strength wood‐based composites. By using scanning electron microscopy (SEM), and energy‐dispersive spectroscopy (EDS), the strengthening mechanisms of the high‐performance DWLCs were investigated. Due to both the surface of the cell lumen and cell walls being filled with PF resin, the wood microstructure was cured under high pressure so that the DWLCs were enhanced. [ABSTRACT FROM AUTHOR]

High‐performance composites reinforced with natural fibers are next‐generation structural materials due to their recyclability and light weight. Manufacturing composites with high strength has been a challenge. Here, we describe the manufacture of novel composites reinforced with wood fibers using densification by hot‐pressing and fixing by curing reaction with phenolic resin. This composite with 1.4 g/cm3 had high mechanical properties, high water stability, and aging‐resistance, and exhibited a flexural strength and internal bonding strength of 102.4 and 7.5 MPa, respectively. The strength and modulus are 1.5–6.0 and 1.3–28.1 times higher than those of most of the wood fibers reinforced composites. After immersing in water for 24 h, the water absorption and thickness swelling are only 1.3% and 0.8%, respectively. Scanning electron microscope characterization indicates that the cell wall is totally collapsed and became complete densification. And the collapsed cells are fixed by phenolic resin. This production strategy for the composites was shown to be universally effective for various species of natural fibers. These novel wood fiber‐reinforced composites were suitable for commercial manufacture in the current production line, making them a low cost and high‐performance alternative to automotive and aerospace industries. [ABSTRACT FROM AUTHOR]

Highlights Natural fiber/resin composites exhibit poor fiber–matrix compatibility and easy combustion. In this study, jute‐fiber‐reinforced epoxy resin was used to prepare composite materials by adding marine shell powder, which is a natural non‐combustible inorganic filler that originates from a variety of sources. The morphology, composition, thermal stability, combustion performance, and mechanical properties of the prepared composites were tested using several characterization methods. The results show that the marine shell powder was evenly distributed in the epoxy resin and did not affect the adhesion between the epoxy resin and the jute fiber. When 20% marine shell powder (SMJF20) was added to the jute‐fiber‐reinforced epoxy resin composite, the pyrolytic residual content was 21.88% (60.2% higher than that without), and the maximum heat release rate was 350.75 kW/m2 (22.8% lower than that without). The total heat release and total smoke release of SMJF20 were also 13.9% and 30% lower than that of MJF, respectively. The addition of marine shell powder did not significantly affect the tensile strength, whereas the tensile modulus of SMJF20 increased by approximately 13.9%, the fracture strain decreased by approximately 13.4%, and the bending strength and modulus decreased by approximately 12.9% and 13.0%, respectively. Marine shell powder is an ideal biomass filler for jute‐fiber‐reinforced epoxy resins. Jute‐fiber‐epoxy composites fortified with non‐combustible marine shell powder. Effective filler distribution without compromising epoxy‐jute fiber adhesion. 20% marine shell powder significantly reduces heat release and smoke release. Tensile strength unaffected; tensile modulus and residual content increased. Marine shell powder proves ideal for enhancing epoxy resin with jute fibers. [ABSTRACT FROM AUTHOR]