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Although cross-linking modification by polycarboxylic acid greatly improves dimensional stability and decay resistance, it causes severe brittleness and rigidity in wood. Introducing polyols into the cross-linking network could improve the flexibility of the modified wood, however, the related research is limited, especially the relationship between the strength and the reaction. In this study, poplar wood was modified by cross-linking with 1,2,3,4-butanetetracarboxylic acid (BTCA). D-sorbitol (SO) and sucrose (SU) used as the polyols were introduced to the modification system to esterify with BTCA. The physical and mechanical properties of the resulting wood were investigated. The effect mechanism and microstructure of the wood were also examined. The findings demonstrated that a cross-linked structure was formed in wood with increased ester bonds and ample polymer filling in the lumens. SU has lower leachability than SO. Although the incorporation of polyols has lowered anti-swelling efficiency, the reduction of modulus of rupture caused by BTCA treatment could be redeemed by reducing the degree of cross-linking between BTCA and wood components, especially SO-BTCA treatment. The addition of polyols has slight impact on the modulus of elasticity of BTCA treated wood. [ABSTRACT FROM AUTHOR]

Fabricating wood‐plastic composites (WPCs) using recycled plastic and wasted biomass materials is one of the effective approaches to alleviate the global energy crisis and reduce carbon emission. However, the unsatisfactory mechanical properties and fire safety hazards significantly limit the application of WPCs. Herein, recycled high density polyethylene (R‐PE), bean dregs and intumesce flame retardant (IFR) were melt‐blended into flame‐retardant WPC by mechanochemical crosslinking. The results show that the as‐prepared WPC within 22 wt% IFR achieves a satisfactory UL‐94 V‐0 rating and a limiting oxygen index of 31.0%, exhibiting a 40%, 27.6%, and 16.4% reduction in peak heat release rate, total heat release and total smoke production respectively compared to controlled WPC. The results also revealed an unexpected improvement in the mechanical performance of WPCs using the strategy (elevation of 73.6% in the elastic modulus and 75.9% in the breaking elongation, respectively), which can be attributed to the improved interfacial compatibility between R‐PE, bean dregs and IFR. This work offers an innovative and feasible approach for fabrication of high‐performance fire‐retardant WPC based on recycling waste plastics and agriculture wastes, and contributing to the circular economy and sustainability in accordance with the greening strategy in the world. [ABSTRACT FROM AUTHOR]

A green and sustainable soybean flour (SF) adhesive is considered as a potential alternative to toxic formaldehyde‐based resins. Nevertheless, poor bond stability and low bonding strength is caused by the uneven size distribution and low reactivity of SF. Herein, SF adhesives with excellent and stable performance are synthesized via the synergistic action of high‐pressure homogenization (HPH) treatment by incorporating a green crosslinker. Specifically, an even distribution of the SF particles is obtained after the HPH treatment, from which large soy protein molecules are broken to several small and even single protein molecules. In this way, the adhesion stability is improved. Additionally, more active groups buried in proteins are exposed after the HPH treatment due to the unfolding of the protein molecules. Therefore, a more reactive SF is obtained and thus forms a denser crosslinking structure of resultant the adhesive, providing an increase in bonding strength. Particularly, the effects of homogenizing pressure on the adhesive performance are investigated. The results show that a 215.6% increase of wet bonding strength (1.01 MPa) is obtained after the HPH treatment with a homogenizing pressure of 20 MPa, meeting the standards (GB/T 9846‐2015) for interior applications. [ABSTRACT FROM AUTHOR]