预压缩处理施胶技术提高杨木重组木尺寸稳定性的研究  

Improvement of dimensional stability of poplar scrimber by pre⁃compression treatment gluing technology

作　　者：林秋琴 张亚梅[1] 于文吉[1] LIN Qiuqin;ZHANG Yamei;YU Wenji(Research Institute of Wood Industry,Chinese Academy of Forestry,Beijing 100091,China)

机构地区：[1]中国林业科学研究院木材工业研究所,北京100091

出　　处：《林业工程学报》2021年第1期58-67,共10页Journal of Forestry Engineering

基　　金：National Natural Science Foundation of China(31700482).

摘　　要：高性能重组木制造技术可将速生材制造成具有高强度和天然木材纹理结构的新型木材,从而提高速生材的附加值。然而,采用此技术制备的重组木虽然尺寸稳定性显著高于传统工艺制备的重组木,但是仍不能满足室外用材的需求。为提高室外用重组木的尺寸稳定性,采用预压缩处理施胶技术对木单板施胶后制备高性能重组木,通过扫描电镜、压汞仪、激光共聚焦显微镜和超景深显微镜,研究了预压缩处理施胶技术对木单板和重组木的形貌和胶液分布的影响,及其对重组木尺寸稳定性和力学性能的影响。研究结果表明:预压缩处理施胶技术增大了木单板的比表面积,使胶液在单板和重组木中分布更均匀,而且显著降低了重组木的吸水厚度膨胀率(TSR)和吸水宽度膨胀率(WSR)。在63℃/24 h的水煮测试中,TSR和WSR相比未处理材分别降低43.34%和12.82%;在28 h循环测试中,TSR和WSR相比未处理材分别降低50.94%和51.48%。因此,采用预压缩处理施胶技术制备的重组木尺寸稳定性相比未处理材显著提高。同时,重组木的静曲强度、弹性模量和剪切强度相比未处理材分别提高1.63%,12.15%和21.34%。As one of the fastest⁃growing wood resources,poplar wood is widely used in many fields.However,the uti⁃lization of the polar wood is limited due to its poor mechanical properties,high hygroscopicity and low dimensional stability.A novel technique for the manufacturing of wood scrimber was proposed by the Research Institute of Wood Industry,Chinese Academy of Forestry.The wood scrimber produced by this novel method had enhanced mechanical properties and an improved dimensional stability compared with solid wood and other wood⁃based composites.There⁃fore,it was a promising alternative to high⁃quality hard wood.However,the dimensional stability of the wood scrim⁃ber manufactured by this novel approach was still not good enough for outdoor products.The liquid penetration of pre⁃compressed technology was developed in the manufacture method of wood scrimber to improve the dimensional stabili⁃ty for outdoor applications.In the glue impregnation process,the oriented wood fiber mats(OWFMs)were immersed in the phenol formaldehyde(PF)resin with pre⁃compressed treatment by repeating several times and then were made for wood scrimber(WSP)by hot⁃pressing.The scanning electron microscope(SEM),mercury intrusion porosimetry(MIP),laser scanning confocal microscope(LSCM)and ultra⁃depth three⁃dimensional microscope(UTDM)were used to examine the changes of OWFMs and wood scrimber in the microstructure and resin distribution,as well as the physical and mechanical properties.The relationship between the internal structure,the distribution of PF resin,and the physical and mechanical properties of the wood scrimber were established.The results showed that the OWFMs with the pre⁃compressed treatment had higher specific surface area and the PF resin penetrated more deeply and distri⁃buted more uniformly in OWFMs and WSP.Meanwhile,the densification of the WSP increased compared with that of control samples at the same density.As a result,the thickness swelling rate(TSR)and the width swelling rate(WSR)of the WSP d

关 键 词：重组木 预压缩处理施胶技术 尺寸稳定性 力学性能 

分 类 号：S781.7[农业科学—木材科学与技术]