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家具和地板用浸渍改性杉木研究进展 总被引：2，自引：0，他引：2
《林业工程学报》2016,(5)
杉木是我国南方重要的速生林树种之一,但其木材存在诸多缺陷,极大地限制了其在家具、地板中的进一步开发利用。将杉木进行浸渍改性以提高综合利用率是解决全球木材的供需矛盾和家具、地板用材短缺的重要手段之一。浸渍改性目前主要应用的树脂有UF树脂、PF树脂、聚乙烯醇缩甲醛、MF树脂等,其中以PF应用较常见,其改性效果较为显著。浸渍改性过程中,主要有真空处理、真空加压、抽提后常压浸渍或真空浸渍等浸注方法,辊压浸注作为常温常压条件下高效快速浸注处理木材的方法也可用于杉木的浸渍改性,真空-叠压法既能保证改性药剂完全渗入杉木木材,也能防止杉木试材在压力下被压溃。不同的浸渍工艺参数和树脂固化条件对改性后杉木性能影响不同:浸渍时间对浸渍材的吸水率及吸水厚度膨胀率影响较大,热压温度、热压时间与压缩变形恢复率、静曲强度密切相关,各工艺因素间存在一定的相互关系和影响。最后讨论了浸渍改性杉木在家具、地板业中的发展方向与应用前景,为杉木浸渍改性的进一步研究和应用提供参考。 相似文献
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木材是绿色环保可再生材料，固碳、降碳优势明显；但部分木材渗透性差，极大制约了木材的干燥、改性、浸渍处理等后续加工。改善木材渗透性可以节省加工成本，降低加工难度，有效提高木材的性能和功能。木材渗透性的物理改性方法是指通过外力破坏木材的薄弱结构，因其属于环境友好型且效率较高，近些年的研究也相对较多。文中总结了木材渗透性的影响因素(木材结构、加工工艺、流体性质)及改性方法，重点阐述了近几年研究较多的微波处理、超临界CO2处理、超声波处理等物理改性方法的机理及研究进展，分析比较了不同物理改性方法之间的差异和研究中存在的问题，最后指出未来关于木材渗透性物理改性方法研究的潜在领域及发展方向，以期为木材渗透性改善技术的后续研究和应用提供参考。 相似文献
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以杉木、马尾松木材和中密度纤维板、刨花板为试材,利用超临界CO2携带戊唑醇对试材进行防腐处理,研究超临界CO2流体辅助防腐处理工艺对戊唑醇的留着率以及分布状况的影响。结果表明,随着处理压力的增大,试材中戊唑醇的平均留着率和分布梯度都增大;温度对戊唑醇剂的留着率影响较复杂,处理温度45℃,留着率最高,同时温度与戊唑醇分布梯度没有明显的相关性;处理时间以30 min为宜。 相似文献
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超临界 CO2 萃取落叶松木材挥发油的工艺研究 总被引：1，自引：0，他引：1
采用超临界CO2萃取技术萃取落叶松木材挥发油,以得率为考察指标,研究了萃取压力、萃取温度、CO2流量和萃取时间对得率的影响.确定了超临界CO2萃取落叶松木材挥发油的最佳工艺参数:萃取压力35MPa,萃取温度60℃,CO2流量10kg/h,萃取时间2h,在此条件下挥发油得率可达0.57%. 相似文献
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为探讨浸注工艺对木材增重率的影响,以PF树脂为浸注材料,以树脂浓度、压缩次数、保压时间、浸渍时间和压缩率为试验因素,采用单因素试验方法在平压浸注装置上对杨木试件进行了浸注填充。结果显示:2次压缩较1次压缩,杨木木材增重率增加了20. 2%;保压时间从0 min延长至10 min,杨木木材增重率增加了11. 5%;浸渍时间从1 h延长至2 h,杨木木材增重率提高了8. 8%;再增加压缩次数、延长保压时间和浸渍时间,杨木木材增重率均变化不大;而杨木木材增重率随PF树脂浓度和杨木木材压缩率增加呈线性增加,PF树脂浓度与压缩率对杨木木材增重率具有显著影响。因此选择压缩次数为2次,保压时间为10 min,浸渍时间为1 h,PF树脂浓度与杨木木材压缩率由改性木材的用途决定。 相似文献
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Richard Wascher Christian Kühn Georg Avramidis Sascha Bicke Holger Militz Gisela Ohms Wolfgang Viöl 《Journal of Wood Science》2017,63(4):338-349
This study investigates the dimensional stability and mechanical properties of plywood boards made of thermally modified and unmodified beech veneers that have undergone plasma pre-treatment before melamine resin impregnation. The water and melamine resin uptake and resulting weight percent gain of the veneers were investigated, whereby the air plasma pre-treated veneers showed improved liquid uptake. Five-layer plywood boards were then manufactured and tested for their dimensional stability, compressive strength, bending strength, and tensile strength. Plywood boards made of thermally modified and plasma pre-treated veneers showed a significantly improved dimensional stability, along with small influences on their mechanical properties. 相似文献
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Thomas Walther S. Nami Kartal Won Joung Hwang Kenji Umemura Shuichi Kawai 《Journal of Wood Science》2007,53(6):481-486
The development of oriented fiberboards made from kenaf (Hibiscus cannabinus L.) and their suitability as a construction material has been investigated. Three different types of boards consisting of
five layers with individual orientations were prepared using a combination of low molecular weight and high molecular weight
phenol-formaldehyde (PF) resin for impregnation and adhesion purposes. Additional boards with the same structure were prepared
using high molecular weight PF resin only. The mechanical properties of the boards have been examined as well as their resistance
against fungal decay and termite attack. All kenaf fiberboards showed elevated mechanical properties compared with medium-density
fiberboard made from wood fibers, and showed increased decay and termite resistance. Differences in the decay and termite
resistance between the board types were caused by the presence of the low molecular weight PF resin for the impregnation of
the fibers. No significant difference was found for the mechanical properties. The effect of the PF resin for impregnation
was much clearer in fungal decay resistance than for termite resistance; however, fiber orientation had no effect on both
decay and termite resistance of the specimens. 相似文献
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利用广义神经网络建立了树脂浸渍模型,该模型可实现常压浸渍和辊压浸渍中树种、单板纹理、单板,厚度。树脂固体含量、浸渍时间或辊筒间隙等几方面因素与单板增重率之间的高精度映射,从而进行树脂浸渍量的实时调控。模型相关系数均大于93％,平均相对误差均小于10．2％。 相似文献
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To improve the impregnation of wood, the pre-treatment by compression was systematically studied in terms of effects of compression ratio, compression direction, compression speed and compression-unloading place on the liquid impregnation in poplar and Chinese fir. The results showed: the impregnation increased 0.0065 or 0.0074 g/cm3 for every 1% increase of compression ratio when the compression ratio was lower or equal to 50 and 40% for poplar and Chinese fir, respectively; it continued to increase afterwards while the variation was quite big. There existed a significant difference of the impregnation of wood compressed at different directions in Chinese fir, but not in poplar. There existed a significant difference of the impregnation of wood compressed at different speed in both species. The impregnation of wood is likely to be in favor of radial compression in terms of the amount of impregnation. 5 and 10 mm/min were recommended as a compromise of impregnation and pre-treatment efficiency. The impregnation of wood that the compression unloaded in water was about 18.2 (poplar) and 9.2% (Chinese fir) higher in amount and was much quicker in speed than that the compression unloaded in air, and the difference between them was significant, suggesting that compression unloaded in water is significant to improve the impregnation. 相似文献
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介绍了单板层积材、密实型单板层积材在国内外的研究和利用概况.探讨了采用低分子量酚醛树脂浸渍处理杨木单板的方法制备杨木单板层积材的生产技术.结果表明:施胶量相当时,浸渍方式与涂胶方式生产的单板层积材相比,密度相当,吸水厚度膨胀(24hTS)降低了24%,胶合强度提高了:16%,弹性模量(MOE)和静曲强度(MOR)分别提高了20.17%和44.76%.采用浸渍树脂方式生产的密实型强化杨木单板层积材随着吸药量的增多,密度增大;24hTS减小;胶合强度随着吸药量的增加先增大而后趋于平稳;MOE和MOR先增大后减小.当吸药量为168%时,MOE、MOR达到最大,分别为15.34GPa和135.31 MPa.密实型强化单板层积材能够满足建筑和木结构等结构材要求,具有良好的发展空间. 相似文献
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