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Study on physical and Mechanical properties of poplar Modified by phenol-formaldehyde resin

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chinese forestry Science and Technology 2008年第1期7卷 82-87页

作者： chai yubo1 {2. Huanrong1 {2. junliang1 LI Longzhe2.TANG Deguo3 1.research institute of wood industry, chinese academy of forestry, beijing 100091, p.r.china 2. Construction Bureau of Yanbian Korean Autonomous prefecture, Yanji 133000, p.r.china 3. forestry Bureau of wangqing County, wangqing 1332.0, p.r.china

Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concentration of 30% under vacuum-pressure process, and then dried and machined according to the related standards. The results show that the physical and mechanical properties of poplar can be improved by the treatment, except for toughness. The average density of poplar increases from 0.397 to 0.710 g/cm3, the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain of treated specimens increase by 56.71%, 112.97% and 87.69%, respectively, compared to the untreated. And the hardness values on radial and tangential sections, and nail holding power as well as abrasion resistance of treated specimens improve by 2.3.87%, 82.78%, 71.43% and 2..06%, respectively; while toughness decreases by 48.80%.

关键词： phenol-formaldehyde modification impregnation I-72.poplar (populus xeuramericana) density strength plantion physical mechanical property

Impact of Drying Methods on Wettability of populus tomentosa

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chinese forestry Science and Technology 2008年第3期7卷 56-60页

作者： ZHOU Yongdong JIANG Xiaomei liu junliang {2. yubo wang Jing wang Shu Key Lab of wood Science and Technology of State forestry Administration research institute of wood industry, {12., beijing 100091, p. r. china

plantation poplar is one of the most important resources for wood industry, its utilization field is vast. The wettability of populus tomentosa with different drying methods was judged by measurement of contact angle using distilled water in this paper. The results showed that the specimens from conventional drying have the biggest contact angle, and the air dried have the smallest contact angle, air dried lumbers have a better wettability than the kiln dried. The changes of contact angle in a period of time showed wettability sequence of lumber with different drying methods: air drying > high temperature drying > conventional drying. The basic property for high value-added plantation poplar lumber products was provided to the wood industry.

关键词： air drying conventional drying high temperature drying poplar (populus tomentosa) contact angle wettability

review on resin-treated wood

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chinese forestry Science and Technology 2007年第1期6卷 19-24页

作者： chai yubo {2. Huanrong {2. junliang research institute of {2. industry. chinese academy of Foresty Beijing 100091. P.R.China

Adding low molecular weight resins into wood can overcome wood intrinsic defects, which is a new approach for the high efficient utilization of plantation. This paper reviews the {2.es on low molecular weight resins modifying wood, including different impregnating resins, impregnation technologies, properties of treated wood and mechanism of modifying wood. In the end, some suggestions and prospects are put forward.

关键词： wood low molecular weight resin impregnation modify

Characteristics of Larch Bark pyrolysis and Analyses on Liquid pyrolyzate Components

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chinese forestry Science and Technology 2007年第1期6卷 14-18页

作者： YAN Zhen ZHAO Yong chai yubo {2. Yurong wang Shu School of Material Science and Technology. Beijng forestry University Beijing 100083 P.R.China research institute of {2. industry Chinese Academy of Forestry. Beijing 100091 P.R. China

This paper studies the characteristics of larch bark pyrolysis and analyzes factors that affect the pyrolysis and the liquid pyrolytic component. The results are as follows: TG curve shows that the pyrolysis can be divided into three parts: drying process, pyrolytic process, and carbonate and calcinated process. Both the size of grain and the temperature rising rate affect the shape of TG and DTG. Vinegar and sedimentary tar are main components of pyrolyzate products. GC-MS is applied to analyze vinegar. It is shown that the vinegar is a highly complex compound which is composed of phenol and its derivatives (45.62.%), organic acid (13.851%), keto derivatives (9.754%), aldehydic derivatives (8.573%), alcoholic derivatives (1.794%), ester and its derivatives (0.2.5%).

关键词： bark pyrolysis vinegar larch Larix gmelini

利用红外成像和纳米压痕测试技术研究热处理落叶松管胞性能

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林业工程学报 2022年第3期7卷 67-72页

作者：王喆孙柏玲柴宇博刘君良中国林业科学研究院木材工业研究所北京100091 浙江农林大学化学与材料工程学院杭州311300

以我国主要用材树种日本落叶松木材为研究对象,采用物理改性方法真空热处理技术对其材质进行改良。利用场发射扫描电子显微镜和傅里叶变换红外成像显微镜研究不同热处理条件(160~2.0℃温度范围,处理4 h)下落叶松木材晚材管胞细胞壁形态... 详细信息

以我国主要用材树种日本落叶松木材为研究对象,采用物理改性方法真空热处理技术对其材质进行改良。利用场发射扫描电子显微镜和傅里叶变换红外成像显微镜研究不同热处理条件(160~2.0℃温度范围,处理4 h)下落叶松木材晚材管胞细胞壁形态、化学组分结构和分布的变化规律,并结合纳米压痕测试系统研究热处理木材细胞壁力学性能变化趋势。结果表明:木材热处理过程中,随着热处理温度的升高,晚材管胞细胞壁出现裂纹并增加;半纤维素发生降解,细胞壁红外成像中半纤维素相对高浓度分布区域逐渐减少,木质素高浓度分布区域呈现先增加后降低的趋势,表明该过程中木质素发生了热解并进行了重新分布。木材细胞壁压痕弹性模量和硬度随着真空热处理温度的增加呈先增大后降低的趋势,其中当热处理温度为2.0℃时,压痕弹性模量和硬度相比素材分别增大54.57%和45.69%,达到最大值,该变化规律与木材细胞壁中木质素分布变化趋势相吻合。以上研究结果有助于深入理解真空热处理木材性能的变化,为真空热处理改性木材工艺优化提供理论依据。

关键词：日本落叶松晚材管胞真空热处理红外成像纳米压痕

苯酚-三聚氰胺脲醛树脂浸渍改性人工林杨木的性能分析

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中国人造板 2019年第12期26卷 15-18页

作者：柴宇博唐召群刘君良中国林科院木材工业研究所

为提高人工林杨木的物理、力学、阻燃及防腐性能,采用不同浓度的苯酚-三聚氰胺脲醛(pMUF)树脂浸渍处理人工林杨木,并对改性材的各项性能进行评价。结果表明:相比未处理材,经过不同浓度pMUF树脂浸渍处理后的改性材,其密度、抗胀率、抗弯... 详细信息

为提高人工林杨木的物理、力学、阻燃及防腐性能,采用不同浓度的苯酚-三聚氰胺脲醛(pMUF)树脂浸渍处理人工林杨木,并对改性材的各项性能进行评价。结果表明:相比未处理材,经过不同浓度pMUF树脂浸渍处理后的改性材,其密度、抗胀率、抗弯弹性模量、抗弯强度、氧指数及耐腐性均随pMUF树脂浓度的增大而提高,吸湿率随pMUF树脂浓度的增大而降低,游离甲醛释放量均≤0.3 mg/L。

关键词：杨木苯酚-三聚氰胺脲醛树脂浸渍改性