CAJ | 학술논문

为提高速生材的应用品质,以速生杨木为研究对象,利用交联型木材改性剂对其进行化学改性,对改性前后速生杨木的应力松弛及断面密度进行了测定,采用 X 射线衍射仪(X-ray diffraction,XRD)、傅里叶红外光谱分析仪(fourier transform infrared spectroscopy(FTIR))、X射线光电子能谱仪(X-ray photoelectron spectroscopy, XPS)和扫描电镜-能谱分析仪(scanning electron microscope with energy dispersive X-Ray analysis(SEM-EDXA))对改性机理进行分析.结果表明,经过化学改性,木材应力松弛随着改性剂用量的增加而降低,木材的相对应力松弛值从95%下降到90%和88%,并且配方F 的相对应力松弛值达到了最小值(74%),木材塑性提高,同时平均密度由429.18 kg/m3提高到669.93 kg/m3.XRD谱图显示改性后纤维素晶体结构并未遭到破坏,木材特征峰在衍射角2θ为17°、23°和37.5°的峰位置并没有改变,但是木材的结晶度显著提高.FTIR谱图显示改性剂中的功能性基团与木材结构发生了化学交联反应.XPS结果表明,改性后的木材氧与碳的原子浓度比增加,说明改性剂与木材发生化学交联反应从而含氧官能团增加.SEM-EDAX显示改性材横切面上的导管及木纤维的微孔结构被木材改性剂填充,并且碳元素和氮元素均匀地分布在木材细胞壁及细胞间隙,甚至细胞腔内.
위제고속생재적응용품질,이속생양목위연구대상,이용교련형목재개성제대기진행화학개성,대개성전후속생양목적응력송이급단면밀도진행료측정,채용 X 사선연사의(X-ray diffraction,XRD)、부리협홍외광보분석의(fourier transform infrared spectroscopy(FTIR))、X사선광전자능보의(X-ray photoelectron spectroscopy, XPS)화소묘전경-능보분석의(scanning electron microscope with energy dispersive X-Ray analysis(SEM-EDXA))대개성궤리진행분석.결과표명,경과화학개성,목재응력송이수착개성제용량적증가이강저,목재적상대응력송이치종95%하강도90%화88%,병차배방F 적상대응력송이치체도료최소치(74%),목재소성제고,동시평균밀도유429.18 kg/m3제고도669.93 kg/m3.XRD보도현시개성후섬유소정체결구병미조도파배,목재특정봉재연사각2θ위17°、23°화37.5°적봉위치병몰유개변,단시목재적결정도현저제고.FTIR보도현시개성제중적공능성기단여목재결구발생료화학교련반응.XPS결과표명,개성후적목재양여탄적원자농도비증가,설명개성제여목재발생화학교련반응종이함양관능단증가.SEM-EDAX현시개성재횡절면상적도관급목섬유적미공결구피목재개성제전충,병차탄원소화담원소균균지분포재목재세포벽급세포간극,심지세포강내.
@@@@Wood is one of the oldest renewable resources used by human activity because of its many excellent material properties, such as good mechanical strength, aesthetic appearance, and easy processing. The main components of wood are cellulose, hemicelluloses, and lignin, accompanied by minor contributions of low molecular weight compounds and mineral salts. The major drawback of wood, intrinsically connected with the structure of its three main macromolecular components, is that it is easily affected by environmental factors, such as light, water, temperature, and biological organisms. Wood modification is a generic term describing the application of chemical, physical, and biological methods to improve its’properties. The aim is to improve the performance of the wood, including improvements in dimensional stability against moisture and bio-deterioration, mechanical property, and weathering resistance. In the case of chemical modification, this involves treatment with various chemical polymers to reduce the content of hydroxyl groups. To enhance the applied quality, the functional wood modifier was used to modify the fast-growing poplar. The stress relaxation and the profile density of fast-growing poplar were analyzed. Moreover, the fast-growing poplar was characterized by the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Scanning Electron Microscope with Energy Dispersive X-Ray Analysis (SEM-EDXA). The results demonstrated that the plasticity of wood enhanced for stress relaxation dropped with increasing amounts of modifier. The XRD analysis showed that the crystalline properties of wood obviously increased, but the ordered structure of the crystalline region on the remaining cellulose was not disrupted after modification. FTIR data confirmed the cross-link reaction between wood fiber and modifier. The XPS analysis results indicated that the content of carbon elements decreased while of oxygen elements increased. The SEM-EDXA showed that the wood modifier dispersed in wood fiber and other vertical cells and the N and C had better interfacial adhesion and dispersion between cell wall, intercellular space and even the nucleus of wood cells. The originality of this paper is in the modification of fast-growing wood using the method of vacuum-pressure-vacuum impregnation with a chemical multi-solution. Moreover, the chemical modification overcomes the uneven distribution of modifier in the wood inner structure. The reaction between wood and modifier is a netted site reaction, depicted as two steps. First, the pre-polymer, urea, and catalyst were sufficiently mixed before impregnation. Then, the fresh, natural wood was soaked in water. It also can be seen that the vessels and cell walls of the wood were open. After the impregnation of the wood cross-section, the wood modifier was evenly distributed in wood fiber and other vertical cells after thermal treatment. The wood modifier reacted with the wood fibers, forming networks and exhibiting higher physical properties and dimensional stability. Further work should be performed to develop the multi-function modifier, and is currently under investigation in our laboratory.