【作者】 艾军；

【导师】 陆仁书；

【作者基本信息】 东北林业大学 ， 木材科学与技术， 2001， 博士

【摘要】 我国农作物生产结构中，小麦是最主要的粮食作物之一，每年废弃的秸秆较多，在给环境带来了严重污染的同时，也造成了资源的浪费。因此，如何开发利用麦秆，早已引起人们的密切关注，更是目前所面临的一个重要研究课题。迄今为止，麦秆人造板的研究主要基于异氰酸酯麦秆人造板，但由于异氰酸酯的特性及成本等问题，使得用异氰酸酯生产的麦秆人造板，在国内、甚至国外，广泛实现工业化和被市场认同的速度极慢。为了适应市场需求，采用价格低廉的脲醛树脂胶生产合格的麦秆纤维板，可极大地缩短麦秆代替木材生产人造板的工业化进程。 为了达到上述目的，本研究首次对热磨法麦秆纤维的本体性能及表面性能进行了研究。利用化学分析法、傅立叶红外光谱（FT-IR）、化学光电子能谱（ESCA）等手段研究了麦秆纤维的化学组成在不同处理条件下的变化规律以及麦秆纤维中纤维素、半纤维素、木素在不同处理条件下的结构变化等。结果表明，在试验条件下，麦秆纤维的溶液抽提物随处理时间的延长有下降的趋势，而主要成分α-纤维素、半纤维素、木素的含量及结构无显著变化；热失重分析表明，在受热温度＜180℃时，麦种纤维及其主要成分无明显的热失重现象。以上研究表明热磨法麦秆纤维有可能代替木纤维作为纤维板原料。 利用ESCA分析方法，对麦秆、麦秆横截面不同层面以及麦秆纤维表面进行了元素和官能团及其含量的分析结果表明，麦秆经热磨法分离不仅去除了角质层，而且其表面具有比麦秆外、内表面都大的极性和反应活性，这些化学特性的研究，进一步表明了用脲醛树脂胶接麦秆纤维生产麦秆纤维板的可能性。 利用FT-IR、ESCA分析方法，证明通过化学接枝可以将单体支链引入麦秆纤维表面，使麦秆纤维表面性能发生变化。通过ESCA分析方法，证明利用plasma对麦秆纤维表面进行处理，可以在保证本体性能的前提下得到高活性的表面。这些开创性的研究结果为麦秆纤维与不同树脂复合，开拓更多的新型麦秆纤维复合材料提供了理论依据。 采用DSC分析技术，研究了麦秆纤维板用脲醛树脂的固化动力学。通过固化反应活化能及固化放热过程了解脲醛树脂的固化，从而为麦秆纤维板热压工艺提供了理论依据。 在麦秆纤维的研究及脲醛树脂固化动力学研究基础上，首次采用脲醛树脂胶接麦秆纤维制得了符合GB/T1718-1999室内型板物理力学性能指标（简称国家标准）的麦秆纤维板。并对脲醛树脂麦秆纤维板的主要工艺参数与性能的关系进行了研究。研究发现，由于麦秆纤维的物理化学特性所致，在设定的试验条件下，麦秆纤维板有着与木质纤维板不同的工艺。与木质纤维板相比，要使麦秆纤维板的性能达到国家标准，麦秆纤维板需要更高的施胶量和板坯含水率；热压温度需低于木质纤维板；在设定的麦秆热磨 东北林业人学博！：学位论义分离条件卜，采用 160℃卜分离的纤维，随着预热处理时间的延长，板性能有所改菩；与木质纤维板相同，密度增加、热压时间延长有利于麦秆纤维板性能的提高。 本文研究表明，麦秆纤维完全有可能代替木材与脏醛树脂胶接生产出合格的纤维板产品；同时由于麦秆纤维可以通过改性的方法，改善与其他树脂的相容性，有可能与其他树脂复合形成新型的上秆纤维复合材料，从而进一步扩人麦秆综合利用途径。更多还原

【Abstract】 Wheat is one of the most popular food plants that been cultivated in China. While providing food supply it also bring a large number of waste wheat straw yearly. Some old process on waste wheat straw such as burning can rise severe environmental problems. Thus, the exploitation of wheat straw has been becoming more and more concerned in China. Usually the isocyanate adhesive will be chosen in the manufacture of wheat straw panel. However, this kind of panel couldn抰 be widespread, especially in China, for the high cost and the characteristics of the isocyanate. Then the purpose of our research is to develop the qualified wheat straw fiber board with UF resin which is cheaper compared with isocyanate. By the way of using chemical analysis, FT-IR and ESCA, a comprehensive analysis have been focused on the bulk and the surface characters of Asplund defi bated wheat straw, which was the first trying in China. The results show that low pressure, longer time and high pressure, shorter time steam treatment were not found to have a large effect on the chemical composition of wheat straw. However, the steam treated wheat straw contains relatively low extracts. By TO analysis, weight loss of wheat straw was not found at 1 80C. All results reveal that wheat straw fiber may possibly replace wood fiber as raw material of fiber board. The surface of wheat straw fiber can be activated after Asplund defibration, because the cuticle have been removed from the surface and the polarity of the surface have been increased. Through ESCA, an analysis, which studies the element composition and functional groups that exist in different sections and on the surface of wheat straw, attests the above results. This process of Asplund defibration is very helpful to the adhesion between wheat straw fiber and UF resin. An other way to increase the activity of wheat straw fiber is to graft some monomer branched chain into the surface of wheat straw fiber. After plasma treatment, the surface of wheat straw fiber has been activated without any impairment on its bulk property. The new results provide a rationale fundament for developing other wheat straw composition. A study on curing dynamics of UF resin for wheat straw fiber board has been carried out by DSC analysis. By the change of the activation energy and the exotherm, the curing course of UF resin is comprehended further. It provides a rationale basis for technology of wheat straw fiber board manufacture. The qualified wheat straw fiber board with UF resin has made in Lab., which met the requirement of GB/T 11718-1999. The relationship between the properties and the technic parameters has been discussed. According to the particular physic and chemical characters of wheat straw fiber, the process of wheat straw fiber board is different to that of wood fiber 桰ll? board. To meet the nation抯 criteria, compared with wood fiber board, the wheat straw fiber board should have higher quantity of UF resin and mat moisture content, lower hot-pressing temperature. Under a setting of pre ?heating condition, the quality of wheat straw fiber board will be improved with the prolonging of pre ?heating time if the defibration carried on at 16OXD. Similar as wood fiber board, the increase in board抯 density and the extension in hot- pressing time will enhance the quality of the wheat straw fiber board on the setting conditions. In conclusion, wheat straw fiber is a qualified alternative of wood fiber in UF fiber board manufacture. Furthermore, after improving the compatibility wit更多还原