文献类型：期刊文献

中文题名：基于空气与蒸汽介质组成比及其压力调控的木材压缩变形永久固定

英文题名：Permanent Setting of Compressive Deformation in Surface-Compressed Wood through Regulation of Air-Steam Medium Composition and Pressure

作者：黄荣凤[1] 何啸宇[2] 王艳伟[2] 孙龙祥[2] 黎静[1] 侯晓鹏[1] 陈章景[3]

第一作者：黄荣凤

机构：[1]中国林业科学研究院木材工业研究所,国家林业和草原局木材科学与技术重点实验室,北京100091;[2]久盛地板有限公司,浙江南浔313009;[3]弗吉尼亚理工学院,美国布莱克斯堡VA24061

年份：2025

卷号：39

期号：4

起止页码：1-20

中文期刊名：木材科学与技术

外文期刊名：Chinese Journal of Wood Science and Technology

收录：;北大核心:【北大核心2023】；

基金：国家自然科学基金项目“基于过热蒸汽压力和介质组成的木材塑性变形永久固定机理及其适用性”(32071690);湖州市重点研发计划项目“劣质材增强及表面高质修饰地板关键技术研发”(2022ZD2049)。

语种：中文

中文关键词：毛白杨;压缩变形固定;空气介质;蒸汽介质;回复率;化学成分

外文关键词：white poplar;setting of compressive deformation;air medium;steam medium;set recovery;chemical components

分类号：S781.7;S792.117

摘要：压缩变形永久固定(定型)是木材密实化技术的关键科学技术问题之一。研究以空气、蒸汽以及两者混合气体为介质,在0.1、0.3和0.5 MPa的介质气体压力下,采用高温加压热处理方法,对表层压缩毛白杨(Populus tomentosa)木材实施180℃、2 h的定型处理。通过分析定型处理对压缩木材的回复率,以及其他物理、化学及力学性质的影响,阐明空气与蒸汽介质组成及其压力对木材压缩变形永久固定的作用机理。在180℃温度、0.5 MPa介质气体压力条件下,以纯蒸汽为介质时,有近80%的压缩变形被永久固定,但只以空气为介质时,仅约54%的压缩变形被永久固定。以空气为介质的热处理虽然会使半纤维素降解,但处理材中乙酸及醛类物质含量远远低于介质中加入50%以上蒸汽的混合介质处理材。说明介质中加入一定量的蒸汽,促进细胞壁组分化学反应,对木材压缩变形固定是至关重要的。基于所有检测样品统计分析结果,吸水回复率与相对结晶度之间的相关关系(r=0.921,p<0.01),比吸水回复率与羟基吸收强度之间相关关系(r=0.557,p<0.05)更密切,间接说明半纤维素降解过程使压缩应力释放,比羟基减少使吸湿性降低对压缩变形的永久固定的贡献更大。与空气介质相比,以蒸汽与空气的体积比为1∶1或蒸汽比例更高的混合气体为介质时,木材吸着水EMC和回复率降幅可以提高50%,木材硬度和表面硬度损失率降低4.6%及以上。空气与蒸汽混合介质处理不仅减少了处理过程中蒸汽的使用量,而且简化了压缩木材的定型处理过程,对降低压缩木的生产成本,实现木材压缩技术的商业化应用具有重要意义。
Permanent setting of compressive wood deformation has been a focus of wood modification.The heated and pressurized air only,steam only,and their mixture were applied as the heating media to treat surface-compressed poplar wood(Populus tomentosa)to study permanent setting.In the heat treatment process,the medium pressures were 0.1 MPa,0.3 MPa,and 0.5 MPa;the treatment temperature was 180℃;the treatment time was 2 hours.The effects of treatments on the set recovery,physical,chemical,and mechanical properties of compressed wood were recorded and analyzed.When steam-only treatment was used,at 0.5 MPa,around 80%of the compression was permanently set,compared to 54%of the compression deformation setting when air-only treatment was used.Although air-only treatment causes hemicellulose degradation,by-products of acetic acid and aldehyde compounds were significantly lower than that when steam-only treatment was applied.The correlation between set recovery induced from water absorption and crystallinity index(r=0.921,p<0.01)was closer than that between set recovery induced from water absorption and hydroxyl absorption strength based on the statistical analysis of the entire sample(r=0.557,p<0.05).It partially explained that hemicellulose degradation process contributed to permanent setting,greater than hygroscopicity decreased due to the reduction of hydroxyl groups.Compared with air-only,when the volume ratio of air and steam was 1∶1 or with steam ratio in the medium,the reduction rate of EMC and set recovery on the treated wood increased by 50%,and the loss rate of wood hardness and surface hardness decreased by more than 4.6%.The mixture of air and steam reduced the amount of steam used in the treatment process and simplified the treatment process.This process significantly reduces the production cost of compressed wood and accelerates the commercial application of wood compression technology.