Yu Tian,Wenyan Guo,Zhuo Huang,Yunyan Peng,Junfeng Hou,Xiaolong Fang,Youming Yu,Wenbo Che
Wood is an attractive bio-based building material whose properties are often affected by environmental moisture, ultraviolet, and fungi. Chemical modification is an effective way to improve wood properties ( e.g. , dimensional stability and decay resistance) and thus extends the service life of its products. However, traditional chemical modifiers often contain mild toxicity or volatiles, which harms the operator and environment. Herein, a carboxylated sucrose (CS) was prepared by a green synthesis route using natural compounds (sucrose and malic acid) and used to enhance the properties of wood. The CS penetrated the wood through vacuum-pressure impregnation, which can self-polymerize and be deposited in the cell lumen and chemically bonded to cell wall components , thus efficiently sequestered within the wood. The CS treated wood (CS-wood) exhibited excellent dimensional stability with 41 % of ASE due to its cross-linking with cell walls. Besides, the modulus of elasticity and compressive strength of CS-wood increased by 21 % and 20 % compared with untreated wood, respectively. Notably, CS can help extend the wood service life by limiting the adsorption and migration of moisture in wood cells to improve the UV and decay resistance of the wood. This whole-process friendly approach to preparing biomass-derived CS modifiers effectively improved wood properties, which may provide innovative concepts and insights for wood modification research.
Dongyue Wang,Qiuhui Ling,Yujing Nie,Yan Zhang,Wenhao Zhang,Hui Wang,Fangli Sun
This paper describes the action mechanism of a waterborne epoxy resin (WEP) cross-linked inside wood and its influence on wood dimensional, thermal, and fungal stability. The WEP prepared by phase inversion was impregnated into wood under vacuum-pressure treatment, followed by in situ cross-linking upon heating to form a hydrophobic network inside wood porous structures. The weight gain and volume increment of the treated wood combined with the morphological observation indicated that the WEP components were able to penetrate into wood cell lumens as well as cell walls, cross-link, and finally fix stably inside them. The good fixation of the epoxy resin network formed in wood reduced the leaching into water. Results from Fourier transform infrared (FTIR) spectroscopy confirmed the reaction between the epoxy and wood. In addition, it was found that the dimensional stability, thermal stability, and decay resistance of wood were improved with the WEP modification. The scanning electron microscopy images clearly showed that brown-rot fungus caused more serious damage to the structure of wood than white-rot fungus.
危险品化学品经营许可证（带存储）