Xinqi Gao,Yafang Lei,Teng Sun,Yuanze Ma,Hao Guan,Li Yan
Enhancing the decay resistance ofPopulus tomentosawood through environmentally friendly methods is crucial for improving its durability and market competitiveness. Lignified twigs (LT), typically unsuitable as timber due to their small diameter, are rich in lignin, which degrades during thermal induction to produce antifungal organic compounds. In this context, the objective of this study was to develop a lignified twig preservative (LTP) by thermal induction from the LT ofActinidia chinensisvar.Jinyang. The antifungal activity of LTP under varying thermal conditions was analyzed, along with its chemical composition. Enzyme activity, cell membrane integrity, and respiratory metabolism in fungi treated with LTP were examined to elucidate antifungal mechanisms. Additionally, the decay resistance of LTP-treated wood was evaluated. Results revealed that LTP produced under N2at 220 °C exhibited robust antifungal activity againstTrametes versicolorandGloeophyllum trabeum, attributed to phenolic compounds such as syringaldehyde, syringone, vanillin, and vanillone. LTP inhibited fungal cellulases, hemicellulases, and ligninases by 30%–60%, disrupted cell membrane functionality, and suppressed respiratory metabolism. Poplar wood treated with LTP demonstrated significantly enhanced decay resistance (mass loss < 10%). This thermal-induced feedback pattern shows great potential for LT in wood preservation.
Zhenju Bi,Li Yan,Zhangjing Chen,Yafang Lei,Guangbin Li
The improvement of wood decay resistance is more inclined to eco-friendly methods such as the application of natural products, but the low durability of some natural products as wood preservatives limits their applications. In this study, vanillin catalyzed by laccase was grafted into poplar wood to increase wood decay resistance and can remain in wood for longer period. The reaction system of vanillin, ABTS, laccase and phosphate buffer solution was impregnated into poplar wood using vacuum-pressure method, and reacted at 40 °C for 6 h. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR) were used to confirm the grafting reaction actually occurring during the process. The decay resistance, leaching resistance and mechanical strength of grafted wood were evaluated. Energy-dispersive X-ray (EDX) mapping was used to characterize the vanillin distribution. The results indicated that vanillin grafted poplar wood had good decay resistance, leaching resistance and higher strength. The mass loss of grafted poplar wood exposed to white-rot fungi [ Trametes versicolor (L. ex Fr.) Quél.] and brown-rot fungi [ Gloeophyllum trabeum (Pers.: Fr.) Murr.] decreased from original 46 and 13% to 9 and 4%, respectively, even after leaching. The modulus of rupture (MOR) and modulus of elasticity (MOE) of the grafted poplar were 11 and 26% stronger than original poplar wood. Vanillin was found in wood cell wall. It was actually esterified onto wood catalyzed by the laccase.
Zhenju Bi,Xinqi Gao,Zhencui Bi,Li Yan,Yafang Lei,Chan Li
The wood used for construction should be able to cope with complex environments, especially water and decay fungi. To enhance the wood’s decay resistance and hydrophobicity, aromatic aldehydes such as vanillin, cinnamaldehyde, syringaldehyde, or protocatechualdehyde were grafted onto wood. The poplar ( Populus tomentosa Carr.) wood was impregnated with (3-aminopropyl) triethoxysilane (APTES) to aminate its cell wall, and then aromatic aldehydes were grafted onto the aminated wood through a Schiff base reaction. The findings indicated that this technique enhanced the leaching resistance of aromatic aldehydes in the wood. Furthermore, the durability level of wood grafted by vanillin or cinnamaldehyde was very durable (mass loss<5 %) even after the leaching test. Modified wood has hydrophobicity, manifested by strong anti-swelling efficiency (ASE), low equilibrium moisture content (EMC), and high water contact angle (>90°, air-dried) in 65 % relative humidity and saturated environments. The characterization of modified wood and its model compounds indicated that aromatic aldehydes were grafted onto the hydroxyl groups of wood through Schiff base under the mediation of APTES. This study obtained an outdoor green building wood with hydrophobic and decay resistance for outdoor use and expanded the application of aromatic aldehydes in wood.
危险品化学品经营许可证（带存储）