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微波处理可以破坏木材的微观结构,有效提高木材的流体渗透性。为探究微波处理木材流体渗透性改善机理,同时为人工林木材的功能化改性研究提供理论依据,文章对杉木、落叶松、樟子松、毛白杨、泡桐及尾巨桉六种木材进行微波处理实验。从扫描电镜图片中可以看出,微波处理后,微波处理材会产生射线薄壁细胞之间或与轴向组织的胞间层处产生破坏、闭塞纹孔的打开、纹孔膜破坏、细胞壁破坏及内含物重新分布等变化。微观结构的破坏导致处理材力学性能下降。其中,微波处理后樟子松、杉木、落叶松、尾巨桉、毛白杨及泡桐的抗弯弹性模量(MOE)较处理前分别下降了31.1%、35.4%、45.6%、5.5%、24.4%和23.2%;抗弯强度(MOR)分别下降了38.4%、29.4%、67.2%、9.1%、34.0%和29.1%。同时,不同树种木材中不同的微观结构破坏形式造成处理材不同的吸水性测试结果。而根据微波处理材的吸水性及力学性能测试结果,可以选择适合用于微波处理后进行功能化改性处理的树种。
Microwave treatment can destroy the microstructure of wood, effectively improve the fluid permeability of wood. In order to explore the mechanism of improving the fluid permeability of wood by microwave treatment and to provide a theoretical basis for the functional modification of plantation wood, six kinds of wood, Chinese fir, larch, Pinus sylvestris, Populus tomentosa, Handle the experiment. It can be seen from the SEM images that after microwave treatment, the microwave treated materials will produce damage to the intercellular layer between the ray parenchyma cells or the axial tissue, the opening of the closed pits, the destruction of the pits, the destruction of the cell wall and Content redistribution and other changes. The destruction of the microstructure led to the reduction of the mechanical properties of the treated wood. The bending elastic modulus (MOE) of Pinus sylvestris, Cunninghamia lanceolata, Larix gmelinii, Eucalyptus urophylla, Populus tomentosa and Paulownia under microwave treatment decreased by 31.1%, 35.4%, 45.6%, 5.5% and 24.4 % And 23.2% respectively. The bending strength (MOR) decreased by 38.4%, 29.4%, 67.2%, 9.1%, 34.0% and 29.1% respectively. At the same time, different forms of microstructure destruction in different species of wood result in different water absorption test results for the treated material. According to the microwave treatment of water absorption and mechanical properties of the test results, you can choose suitable for microwave treatment functional modification of tree species.