纳米氧化铜木材防腐剂的防腐性能和抗流失性研究

以大青杨为试材,进行室内木材防腐试验和实验室水流失试验,研究纳米氧化铜木材防腐剂效果和抗流失性能.研究结果表明:经过纳米氧化铜防腐剂处理后,大青杨试样耐腐能力大大提高,失重率明显减少,当药剂浓度为1.6％时已经达到强耐腐等级.该防腐剂的耐褐腐能力与耐白腐能力相比稍差.不同浓度防腐剂处理后,大青杨试样中防腐剂的保持量随防腐剂浓度的增加而增加.另外,纳米氧化铜防腐剂具有很好的抗流失性能.     

植物源提取物木材防腐剂的研究现状与展望

自然界的许多植物中均含有抑菌性和防虫性物质, 如果将这部分资源开发并用于木材防腐, 来替代和部分替代现有的合成类木材防腐剂, 将会促进人居和生态环境的改善。随着发展绿色、环保型木材保护技术的呼声越来越高, 世界范围内的很多学者广泛开展了植物提取物木材防腐剂的研究。文中对国内外植物源木材防腐剂的研究及其在木材和木制品保护中的利用进行概述, 并对今后的植物源木材防腐剂研究进行展望。     

国外木材防腐技术和研究现状

从木材防腐剂、防腐处理工艺、改性处理及环境特性等几个方面对国外的木材防腐技术及研究现状进行较为系统、全面的介绍,并在此基础上指出木材防腐研究的几个主要方向.木材防腐剂的发展趋势是近期以水载防腐剂为主导,以开发综合性能优良的不含金属的有机防腐剂作为未来的发展方向;木材防腐处理工艺的重点在于增强防腐剂在木材中的渗透性,加速防腐剂与木材之间的固着反应以及开发新型的防腐处理工艺以适应新的防腐剂的需要.改性处理方面主要介绍木材的热处理和化学改性处理在防腐方面的应用现状.木材防腐处理的环境特性则着重介绍LCA技术(生命循环分析技术)以及防腐处理材的废弃处理问题.另外,还简要介绍木材防腐研究机构和协会、木材防腐标准等方面的情况.本文旨在使国内的木材研究者对当前木材防腐技术和研究有一个总体的认识,并在此基础上结合国内的实际情况,发展适于处理中国国内树种及适合市场需求的木材防腐技术,为更科学、更高效地利用国内木材资源提供新途径.     

新型水基防腐剂在木材中的固着机理研究进展

对几种主要的水基木材防腐在木材中的固着机理进行了介绍。其中,在胺/氨铜防腐剂体系中,防腐剂中有效成分与木材实质间的反应主要为木质素及半纤维素中的羧基及羟基发生离子交换反应;在微化铜木材防腐剂体系(MCQ/MCA)中,防腐剂中有效成分通过高分子分散剂与木材纤维间较强的附着力固着在处理材中;而在硼类防腐剂体系中,防腐剂中有效成分的固着机理与铜比较相似,但硼酸盐无法直接固着在羧基及羟基中,因此有效成分的固着研究主要涉及以下两个方面:1)增加硼类防腐处理材的疏水性;2)与有机化学物质复合生成稳定的化合物固着在木材中。     

水载型木材防腐剂中有效成分固着的影响因素

水载型木材防腐剂在木材防腐市场中占据着主导地位,然而其中的有效成分的抗水流失性差是其存在的主要缺点,这在很大程度上是由于防腐处理材在使用前防腐剂有效成分与木材成分之间的固着反应不充分而造成的,因此提高防腐有效成分在处理材中的固着质量是提高抗流失性的关键.笔者对国内外在水载型防腐剂中有效成分固着方面的研究进行了较为系统、全面的介绍,其中包括木材树种、固着的环境温度与相对湿度、固着时间、木材含水率、防腐剂的保持量、防腐剂成分组成等不同因素的影响,并在此基础上提出了今后的研究方向.     

ACQ防腐剂对扭叶松蓝变部分木材力学性能的影响

本文利用三种不同浓度ACQ防腐剂对扭叶松蓝变木材进行浸注处理,其浓度分别为1.2%、2.0%和2.8%.研究其抗弯弹性模量、抗弯强度、冲击韧性和顺纹剪切强度(弦面)与未处理蓝变木材相应力学性能的差异,测试标准参照GB1927～1943-91.研究结果显示,经浸注处理后的试样均达到美国AWPA标准UC4A等级规定的药剂保持量;ACQ防腐处理大约降低了20%扭叶松蓝变木材的冲击韧性,与未防腐处理试样对比,在0.01水平上有显著差异,但不同浓度间差异不显著;三种浓度ACQ处理间以及与未处理的扭叶松蓝变木材的抗弯强度、抗弯弹性模量和顺纹剪切强度差异不显著;随着ACQ浓度的降低,冲击韧性、抗弯强度、抗弯弹性模量和顺纹弦面剪切强度有所增大,但影响都很小.图4表10参6.     

木材防腐剂登记药效试验方法和评价标准探讨

根据《农药管理条例》,对木材防腐剂实施登记管理,有利于提高木材防腐剂产品质量,规范市场秩序,保护人畜健康和环境安全。但由于防腐剂与大田农药存在一定的差异,要求其渗透到木材内部而且需在木材中保持尽可能长久的药效。笔者根据木材使用分类等相关标准的规定,探讨了木材防腐剂在登记时需要进行的试验方法和评价标准。     

木材保护领域7项标准通过专审

为加强对防腐木材质量的检验和监督,规范防腐木材市场,2008年9月,中国木材标准化技术委员会在北京进行了6项国家标准和1项行业标准的审定。《木材防腐剂》规定了水载型木材防腐剂的有效成分配比,适用于木材防腐剂的生产及使用。《防腐木材的使用分类和要求》根据木材及其制品在     

水载型木材防腐剂有效成分的加速固着方法

以铬化砷酸铜(CCA)为代表的水载型防腐剂,逐渐被其他主要有效成分为铜的水载型防腐剂取代,这类防腐剂中的.针对水载型防腐剂抗流失性差的缺点,介绍4种用于加速防腐剂中有效成分在木材中固着的方法,分析了这些方法对水载型防腐剂中有效成分的固着效果,并就如何加速ACQ中有效成分的固着研究进行了分析和展望.     

一种水载型有机木材防腐剂的制备及其性能研究

为了制取不含金属的水载型有机木材防腐剂,选择十二烷基二甲基苄基氯化铵(BAC)、多菌灵和吡虫啉作为木材防腐剂的组分,以5%BAC、2%多菌灵、1%吡虫啉和10%乳化剂的配方,在乳化时间30 min、乳化温度70℃、搅拌速度1 000r/min的条件下进行乳化,得到稳定的水载型有机木材防腐剂.对木材防腐剂进行防腐、防霉实...     

Distribution of preservatives in thermally modified Scots pine and Norway spruce sapwood

Studying the impregnation and distribution of oil-based preservative in dried wood is complicated as wood is a nonhomogeneous, hygroscopic and porous material, and especially of anisotropic nature. However, this study is important since it has influence on the durability of wood. To enhance the durability of thermally modified wood, a new method for preservative impregnation is introduced, avoiding the need for external pressure or vacuum. This article presents a study on preservative distribution in thermally treated Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) sapwood using computed tomography scanning, light microscopy, and scanning electron microscopy. Secondary treatment of thermally modified wood was performed on a laboratory scale by impregnation with two types of preservatives, viz. Elit Träskydd (Beckers) and pine tar (tar), to evaluate their distribution in the wood cells. Preservative solutions were impregnated in the wood using a simple and effective method. Samples were preheated to 170 °C in a drying oven and immediately submerged in preservative solutions for simultaneous impregnation and cooling. Tar penetration was found higher than Beckers, and their distribution decreased with increasing sample length. Owing to some anatomical properties, uptake of preservatives was low in spruce. Besides, dry-induced interstitial spaces, which are proven important flow paths for seasoned wood, were not observed in this species.     

Application areas of synchrotron radiation tomographic microscopy for wood research

Possible applications for synchrotron radiation tomographic microscopy in the field of wood research were tested and evaluated at the TOMCAT beamline (TOmographic Microscopy and Coherent rAdiology experimenTs) at the Swiss Light Source (SLS) at the Paul Scherrer Institute (Villigen, Switzerland). For this study, small cylindrical samples (∅ 1 and 3 mm) were examined with different experimental setups resulting in a nominal voxel size of approximately 1.48 × 1.48 × 1.48 and 3.7 × 3.7 × 3.7 μm³, respectively. Suitability of the TOMCAT microscope for 3D investigations of wood anatomy was tested on several softwood and hardwood species revealing microscopic features (e.g. tyloses, wall thickenings or pits) down to the nominal pixel size. The results suggest that even features in the sub-voxel range can be made visible. Tomographic microscopy was also tested for wood technological applications, i.e. penetration behaviour of a wood preservative and also of three wood adhesives (poly-urethane resins) with different viscosities. Although the experiments with the preservative yielded no clear results, the method seems suitable for examining the penetration of the different adhesives. The adhesive penetrates the wood mainly by the vessels where it can be easily discerned from the wood structure.     

木材保护剂分散体系及其液体渗透性研究概述

木材保护是节约木材资源、提高木材使用质量的重要手段。为了实现长期、高效的木材保护,通常需要对木材进行整体浸渍处理,即通过木材的多孔结构将包含有效成分的木材保护剂分散体系引入木材内部。随着技术的发展,出现了各种不同类型的木材保护剂分散体系,笔者介绍了其分类以及各类型的定义和基本特性,在此基础上分别对溶液、微乳液、乳浊液、溶胶、悬浊液型木材保护剂分散体系在木材中的液体渗透性方面研究进行了概述。对于水溶型木材保护剂而言,木材构造、木材抽提物及处理药剂的性质是影响其液体渗透性的主要因素;油溶型木材保护剂的液体渗透性在很大程度上取决于其溶剂的性质,轻油溶剂比重油溶剂的渗透性更优;乳浊液的液滴粒径与木材纹孔膜上孔隙尺寸相当,因此其渗透性与液滴粒径、树种密切相关;微乳液比乳浊液更易渗透,甚至可部分进入木材细胞壁;溶胶形成胶体粒子后在木材内的渗透与木材构造、胶体粒子粒径及p H等相关;悬浊液型木材保护剂由于粒径较大,在木材内的渗透性不佳,分布也不均匀。分析了该领域现有研究的不足,提出应系统、深入地开展研究,在此基础上改善分散体系在木材中的液体渗透性,并为木材保护分散体系的开发提供指导。     

非离子型石蜡乳液增强防腐木材尺寸稳定性的研究

以马尾松、厚荚相思木材为研究对象,将配方优化的非离子型石蜡乳液稀释液及其与木材防腐剂的混合液分别处理木材,增强木材的尺寸稳定性能。研究表明,制备的非离子石蜡乳液平均粒径0．107μm,木材渗透性能好;经石蜡乳液处理的马尾松木材尺寸稳定性可达85％;石蜡乳液能分别与CCA、ACQ木材防腐剂混溶达到稳定状态,耐强酸强碱;石蜡乳液对ACQ木材防腐剂的载药量影响不显著。     

双钩异翅长蠹生物学特性及用防腐剂TWP防治试验

双钩异翅长蠹是橡胶树锯材及其制品的严重害虫。在海南岛1年完成二至三代,约有16种阔叶材被害。用新的水溶性木材防腐剂TWP进行防治试验的结果:①TWP在木材中保持量1.0kg/m~3,初龄幼虫死亡率100％;②新鲜橡胶树锯材用2％TWP真空加压或振荡加压法处理,药剂保持量不少于3.7kg/m~3,可获得长久的保护效力;③TWP不含氯化酚化合物,对人畜和环境十分安全。     

Treatment of timber products with gaseous borate esters

Summary Several factors which influence the treatment of timber products with vapour phase preservatives such as borate esters are considered. Gas flow rate through the substrate was found to be a significant factor limiting both preservative penetration and its rate of deposition. A theoretical model of the treatment process was developed and tested experimentally to determine the influence of several factors on the retention and distribution of boric acid. Gas flow into the timber product was influenced by permeability, pressure gradient and substrate moisture content. The implications of the findings are considered with regard to the treatment of wood and wood products with gaseous reagents.The authors wish to thank the following for their financial support and interest in this research programme — Rentokil Ltd, Rhone-Poulenc/Manchem Ltd, Forestry Commission, UK and Ireland Particleboard Association (now Panel Products Association), Norbord Highland plc (formerly Highland Forest Products plc), IMPEL     

Impregnation of Scots pine and beech with tannin solutions: effect of viscosity and wood anatomy in wood infiltration

The impregnation process of Scots pine and beech samples with tannin solutions was investigated. The two materials involved in the process (impregnation solution and wood samples) are studied in depth. Viscosity of mimosa tannin solutions and the anatomical aspect of beech and Scots pine were analysed and correlated. The viscosity of tannin solutions presents a non-newtonian behaviour when its pH level increases, and in the case of addition of hexamine as a hardener, the crosslinking of the flavonoids turns out to be of great importance. During the impregnation of Scots pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.), the liquid and solid uptakes were monitored while taking into consideration the different conditions of the impregnation process. This method allowed to identify the best conditions needed in order to get a successful preservative uptake for each wooden substrate. The penetration mechanism within the wood of both species was revealed with the aid of a microscopic analysis. Scots pine is impregnated through the tracheids in the longitudinal direction and through parenchyma rays in the radial direction, whereas in beech, the penetration occurs almost completely through longitudinal vessels.     

短轮伐期菇木林栽培试验研究

马褂木具有较强的竞争能力 ,生态适应性强 ,生长快 ,成材早 ,在早期就可表现出速生丰产性能 ,是最佳的短轮伐期菇木树种 ;马褂木既可营造纯林 ,也可营造混交林 ,保存率高达 90 %～ 96 %,明显优于其它伴生树种。杜英、枫香也是适宜的菇木树种 ,杜英生长速度较快 ,与马褂木、厚朴分别混交 ,生长效果都较好。枫香与马褂木混交 ,种间关系协调 ,树种生物学特性互补 ,林分空间结构分布合理 ,是一种成功的混交模式。酸枣生长快 ,适应能力强 ,保持率较高 ,但侧枝多 ,冠幅庞大 ,适合营造混交林 ,且混交比例不宜太大 ;与马褂木混交 ,种间关系协调 ,相互促进生长。厚朴的生长潜力还没有充分发挥 ,需进一步观察。乐昌含笑、白玉兰初期生长缓慢 ,暂不适用作菇木树种。     

A vapour phase preservative treatment of manufactured wood based board materials

Summary The preservative treatment of four different wood based board materials using an esterified borate applied in the vapour phase was investigated. Under optimum conditions complete impregnation via the board faces was achieved in all boards treated. Board moisture content and treatment time had a major influence on retention and depth of penetration of the borate vapour.     

ACQ木材防腐剂及防腐处理木材

为使民众更多的了解和使用ACQ木材防腐剂和防腐处理木材，本文对其基本理化性质、防腐性能、对人、畜和环境的安全性、对木材性质的影响、处理工艺以及注意事项等作了详细的介绍。