摘要
为了提高木材的防水性和尺寸稳定性,以过氧化二异丙苯(DCP)为自由基引发剂,通过硅烷偶联剂的作用,制备出蒙脱土稳定石蜡基Pickering乳液;采用真空-加压方式浸渍处理青杨(Populus cathayana)边材,考察了DCP质量分数对乳液粒径分布和静置稳定性的影响,分析了处理材增重率、表面硬度、表面润湿性、吸水性和尺寸稳定性的变化,并采用扫描电子显微镜(SEM)对处理材的微观结构进行了分析与表征。结果表明:1)制备出的乳液平均粒径达到微米级(≤2μm),DCP为0.05%质量分数时乳液平均粒径最小,随着DCP质量分数进一步增加,乳液粒径有所增大;2)乳液浸渍处理后,处理材的表面硬度、表面润湿性和防水性均有所提高,其中DCP为0.05%质量分数时的改性效果较好;3)连续、均一的蜡状物附着在木材细胞壁纹孔表面,从而使木材具有较高的疏水性。
Wood is a kind of porous material composed of cellulose, hemicellulose and lignin. It contains a large number of hydrophilic hydroxyl groups that are easy to absorb and adsorb water, which may cause deformation and crack- ing. Therefere it is necessary to improve its dimensional stability through wood waterproofing treatment. Picketing e- mulsions are emulsions of any type, either oil-in-water （O/W）, water-in-oil （W/O）, or even multiple, stabilized by solid particles in place of surfactants. Compared with the traditional emulsion with surfactants as emulsifier, Picker- ing emulsion has a wide application prospect due to reducing the amount of surfactants, saving cost and reducing envi- ronmentai pollution. In this study, a kind of paraffin wax based Pickering emulsion stabilized by montmorillonite was prepared by using the silane coupling agent and dicumyl peroxide （DCP） as a free radical initiator. The sapwood of poplar （ Populus cathayana） was impregnated by the emulsion through the vacuum-pressure process. The effect of the mass fraction of DCP on the particle size distribution and the stability of the emulsion were investigated. In addition, the change of weight percent gain, surface hardness, surface wettability, water absorption and dimensional stability of the treated wood were analyzed, and the microstructures of the treated woods were characterized by the scanning elec- tron microscope （SEM）. The results showed that： （ 1 ） The average particle size of the emulsion reached micron （ less than 2 Ixm）. The particle size of the emulsion was minimal when the content of the DCP was 0. 05%. With the in- crease of the mass fraction of the DCP, the particle size of the emulsion increased. （2） The surface hardness, wetta- bility and water resistance of the treated wood were improved after the emulsion impregnation, and the modification effect was the best when the mass fraction of the DCP was 0. 05%. （3） Since the continuous and uniform wax was attached on the surfaces of the w
出处
《林业工程学报》
北大核心
2017年第5期36-40,共5页
Journal of Forestry Engineering
基金
国家自然科学基金(31570542)
