【作者】 王鹏；

【导师】 顾正彪；

【作者基本信息】 江南大学 ， 制糖工程， 2012， 硕士

【摘要】 论文针对目前人造板生产过程中广泛使用的甲醛系列胶粘剂存在有毒有害的现状,研究了一种可以应用于人造板生产的高浓低黏并有一定粘合强度的淀粉基胶粘剂。同时参考目前无胶纤维板制备的研究,探讨了漆酶处理木质原料压制刨花板的工艺条件,并对淀粉胶粘剂与漆酶处理木质原料相结合压制刨花板的工艺参数及粘结机理进行了研究。最后本文还对刨花板的热压工艺进行了探讨,确定了较为经济高效的热压工艺条件。首先,对应用于人造板生产的高浓低黏淀粉胶粘剂的制备及应用进行了研究。以淀粉胶粘剂的黏度和所制刨花板的内结合强度为指标,对淀粉胶粘剂制备过程中酸解氧化预处理工艺、六羟树脂交联改性工艺进行了探讨。最终结合人造板生产工艺的特点选择了最优制备工艺参数,在最优条件下制得的胶粘剂黏度为300.33 mPa·s,将其应用于刨花板的压制,所制刨花板的内结合强度达到0.29 MPa。其次,对单独使用漆酶处理木质原料并压制成刨花板进行了研究。实验发现单独使用漆酶处理木质原料并压制刨花板,所制刨花板的内结合强度仅为0.095 MPa,与无胶纤维板的内结合强度相差较大。文中对产生差别的原因进行了分析,认为刨花板与纤维板的生产原料、生产工艺差别是造成所制板材内结合强度有较大差别的原因。再次,对淀粉胶粘剂和漆酶处理木质原料两种手段相结合压制刨花板进行了研究。实验结果显示,两种手段相结合所制的刨花板内结合强度高于单独使用两种手段压制的刨花板内结合强度之和,具有协同效应。再则,对刨花板生产中的相关粘结机理进行了探讨。结果表明,淀粉与六羟树脂发生了交联反应;漆酶处理使得木材的加工性能发生了有利于刨花板生产的变化。最后对刨花板的热压工艺参数进行了探讨,得到了较为经济、高效的热压参数:热压温度为190℃,采用两段式热压法,先在8 MPa条件下保温3 min,然后加压到12 MPa保温3 min。在最优条件下压制的刨花板内结合强度达到0.42 MPa,达到了刨花板国家标准中要求的0.4 MPa,且所制刨花板无毒无污染,有利于人造板加工业的长远发展和人民群众的切身利益。更多还原

【Abstract】 Now the formaldehyde-based adhesives are widely used in the production of wood-based panels. While in the use of formaldehyde-based adhesives, formaldehyde would relase and be hazardous to human health. Considering of this, we developed a kind of starch-based adhesive with high-concentration and low-viscosity. Besides, process conditions of laccase treatment of the raw material for the production of particleboard was studied, referring to the present study of non-gel fiberboard. And then the starch-based adhesive together with laccase treatment of wood materials were used in the production of particleboard, and the mechanism was also studied. Finally, we foud a more economical and efficient process parameters for hot-pressing.Firstly, the starch-based adhesive with high-concentration and low-viscosity was studied. The pretreatment process of acid hydrolysis-oxidation and cross-linking modification by hexamethoxy methyl melamine were discussed, with viscosity of the starch adhesive and the internal bond strength of particleboard as indicators. The viscosity of the adhesive produced with the optimize conditions was 300.33 mPa·s, and the internal bond strength of particleboard was 0.28 MPa.Secondly, the treatment of wood materials by laccase for the production of particleboard was studied. The results showed that the internal bond strength of particleboard produced by the laccase-treated wood materials was 0.1 MPa, which is much lower than non-gel fiberboard treated by laccase. We think that the differences of raw materials and production process between particleboard and fiberboard were the causes.Thirdly, the production of particleboard by means of starch-based adhesive together with laccase-treated materials was studied. The result showed that the the final internal bond strength of particleboard was stronger than the sum of internal bond strength of particleboards produced by starch-based adhesive or laccase-treated materials alone.Fourthly, the bonding mechanisms were studied. The result showed that a crosslinking reaction occurred between starch and hexamethoxy methyl melamine. Besides, the processing performances of wood materials were improved after being treated by laccase, and these property changes were conducive to particleboard production.Finally, parameters for hot-pressing process of particleboard were studied. Optimum curring temperature was 190℃, take two-stage hot-pressing method, that was keeping particleboard under 8 MPa for 3 minutes and then increase the pressure to 12 MPa and keep particleboard under 8 MPa for 3 minutes.The internal bond strength of particleboards prepared with optimal process parameters reached to 0.42 MPa, and the process and productions were non-toxic and pollution-free.更多还原