杉木苯酚液化产物及树脂的结构与性能表征
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。
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.
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。
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.
引文
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[4]傅深渊,赵广杰等.竹材液化物酚醛树脂胶固化及固化动力学研究.生物质化学工程,2009,43(4)：33～37
[5]顾继友,朱丽滨.脲醛树脂化学构造与胶接性能、甲醛释放量及固化特性关系的研究[J].中国胶黏剂,2003,13(3)
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[7]华毓坤主编.人造板工艺学.北京：中国林业出版社,2002
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[10]李改云,秦特夫,黄洛华.酸催化下苯酚液化木材的制备与表征[J].木材工业,2005,19(2)：28-31
[11]李坚,江泽慧,刘君良.水溶性低分子量酚醛树脂的合成[J].木材工业,2001,15(4)
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[17]任英杰,魏安岭等.煤加氢液化残渣的流变特性研究.燃料化学学报,2007,35(3)：262-267
[18]吴刚.材料结构表征及应用[M].北京：化学工业出版社,2002
[19]谢满华,赵广杰.化学处理过程中木材的分子构造变化与化学流变学特性.林业科学,2005,41(3)：158-163
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[21]余煜.材料结构分析基础[M],北京：科学出版社,2000.9：170～239
[22]杨淑蕙.植物纤维化学[M].3版.北京：中国轻工业出版社,2001：103-105.
[23]张晨霞,黄金田.两种沙生灌木的液化及其产物的FT-IR分析.生物质化学工程,2006,40(4)：15-18
[24]赵才贤,张平,袁军等.PA6/SiO2纳米复合材料的动态力学性能研究.湘潭大学自然科学 学报,2005,27(1)：106-111
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