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杉木苯酚液化产物及树脂的结构与性能表征

Characterization of Structure and Properties of Liquefied Products from Chinese Fir with Phenol and Its Resin

【作者】 陈俊宏

【导师】 赵广杰;

【作者基本信息】 北京林业大学 , 木材科学与技术, 2010, 硕士

【摘要】 本论文选用杉木为原料,苯酚为反应试剂,浓硫酸为催化剂进行液化反应,研究了催化剂含量、液固比及液化时间对液化效率的影响;通过红外光谱、X射线衍射、扫描电镜等方法表征液化产物的结构,通过动态力学分析DMA、热重分析TGA的方法表征液化溶解物的性能,探讨了液化工艺对液化产物的结构及性能的影响;对不同条件的液化产物设定相同的树脂化工艺参数,进行树脂化试验,通过粘度、DMA、TGA等表征树脂的流变学特性,探讨液化工艺对树脂结构及性能的影响。主要结论如下:1.在一定范围内,液化效率随着液固比、液化时间、催化剂含量的增加而升高。2.木材经苯酚液化后,其产物的结晶状态变化如下:17。与22.5。处的衍射峰消失了,结晶形态发生改变;结晶度显著降低,且随液固比、催化剂含量的增大而降低。3.液化产物在测试温度-120~100℃内产生了玻璃态转化温度Tg;在0-50。C范围内观测到α`松弛过程,50~100℃范围内观测到一个α``松弛过程;E`随着催化剂含量的增加而升高;活化能随着液化时间的增加而升高。4.与杉木相比,液化残渣的结构变化如下:(1)22.5°处X射线衍射峰峰强显著增大,结晶区宽度降低,结晶度显著高于杉木的结晶度;(2)FTIR吸收峰的差异主要在2900 cm-1,1696 cm-1及750~818 cm-1附近。5.液化条件对液化物树脂的流变学特性的影响如下:(1)树脂的粘度随液化反应中的液固比的增加而迅速降低,随催化剂含量的升高而增大;(2)存储模量随温度的升高而降低;(3)液化工艺对树脂的热稳定性影响不大。

【Abstract】 In this research, Chinese fir was liquefied with phenol as reagent and sulfuric acid as catalyst. Effect of catalyst content, time and liquid ratio on liquefaction efficiency were studied. Structure of liquefied products was characterized using FTIR, XRD and SEM. Properties of acetone-soluble wood liquefaction were characterized using DMA and TGA. Effect of liquefaction factors on structure and properties of liquefied product were discussed. Resinfication research is done under same parameters using different liquefaction conditions products. Rheology properties were characterized with viscosity, DMA and TGA. Effect of liquefaction factors on structure and rheology properties of wood liquefied resin were discussed. The results are as follows:1. Within limits, liquefaction efficiency increases with the increase of catalyst content, time and liquid ratio.2. After liquefaction, some changes happened to the crystal state of acetone-soluble wood liquefaction:X-ray diffractogram peaks at 17°and 22.5°disappeared and crystal state changes, degree of crystillinity decreases dramatically with the increase of liquid ratio and catalyst content.3. Tg occurs to acetone-soluble liquefied wood at-120~100℃;α" relaxation peak exists between 50~100℃,α’ relaxation peak exists between 0~50℃; E’ increases as catalyst content increasest, activity energy increases as the liquefaction time increases.4. Changes between the structure of wood residue and that of Chinese fir are:a. X-ray diffractogram peak at 22.5°gets stronger, width of crystal area decreases, degree of crystillinity decreases dramatically. b. The differences in FT1R are around 2900 cm-1,1696 cm-1 and 750~818 cm-1.5. Effect of liquefaction parameters on rheology properties of wood liquefied resin is:a. Viscosity of resin decreases quickly with the increase of liquid ratio, while increases with the increase of catalyst content, b. E’ decreases with the increase of temperature and decreases more quickly under higher temperature. c. TGA curves of resin are almost parallel, difference of weight loss rate among the three stages is not obvious.

【关键词】 杉木液化树脂结构流变学
【Key words】 Chinese firliquefactionresinstructurerheology
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