【作者】 刘聪；

【导师】 张洋；

【作者基本信息】 南京林业大学 ， 木材科学与技术， 2011， 硕士

【摘要】 我国森林资源缺乏,随着我国经济快速发展和人民生活水平的提高,木材供需矛盾日益突出。大力发展人工速生林是缓减这一矛盾的有效措施,也是今后相当长时期内补充木材资源供应不足的重要形式。我国杨树资源丰富,速生杨树已经广泛用作人造板原料,有效缓减了我国木材供需矛盾。然而,速生杨木单板质地松软、密度低,限制了杨木胶合板的使用范围；此外,豆胶虽然价廉、量广、可再生、易于施胶操作且无毒无味试用期长,但普通大豆胶黏剂耐水性差、胶合强度低,而且耐腐蚀性差、易于生物降解,所以需要进行改性处理以期提高耐水性以及胶合强度。为此,本论文目的是通过采用杨木微纳纤丝改良豆胶和脲醛胶杨木胶合板的性能,使其能够适应更多的应用途径。本文选用杨木纸浆纤维为原料,研究了超声波破碎仪制备杨木微纳纤丝的工艺。并且,采用扫描电子显微镜、激光粒度分布仪和X射线衍射仪等现代分析仪器,对杨木微纳纤丝的形态、结晶度等性能进行了分析。运用傅里叶红外光谱仪FTIR、差示扫描量热仪DSC、动态热机械分析仪DMA等现代仪器分析方法,研究了杨木微纳纤丝对豆胶的影响。通过DMA分析微纳纤丝改性前后的豆胶,发现微纳纤丝显著改善了豆胶的抗弹性形变能力。通过脲醛树脂和三聚氰胺树脂胶粘剂固化反应的机理,分析杨木微纳纤丝对脲醛树脂和三聚氰胺树脂胶粘剂产生的作用。为了提高杨木胶合板的胶合性能,将杨木微纳纤丝作增强相,在豆胶中加入1%—5%,制造豆胶杨木胶合板,双面涂胶量为480 g/m2,热压温度160℃、热压时间80 s/mm(板厚)、热压压力1.6 MPa。试验结果表明：在豆胶中加入3%杨木微纳纤丝时,豆胶杨木胶合板的胶合强度最高,比未添加微纳纤丝的豆胶杨木胶合板的胶合强度提高了56%。将杨木微纳纤丝作增强相,在脲醛胶中加入1%-10%,制造脲醛胶杨木胶合板,双面涂胶量为280g/m2,热压温度115℃、热压时间75s/mm(板厚)、热压压力1.2 MPa。试验结果表明：在脲醛胶中加入1%-10%微纳纤丝,脲醛胶杨木胶合板的胶合强度提高了35%。为了提高杨木胶合板的表面性能,将杨木微纳纤丝作增强相,在三聚氰胺树脂中加入1%—5%,对杨木胶合板表面进行处理。试验结果表明：在三聚氰胺树脂中添加了3%-5%微纳纤丝后,染色杨木胶合板的色牢度有明显改善,色牢度增加了20%；在三聚氰胺树脂中添加微纳纤丝处理杨木胶合板后,可以不同程度的提高杨木胶合板的表面耐磨性能,其中,添加1%微纳纤丝三聚氰胺树脂处理的杨木胶合板表面耐磨性能最好。更多还原

【Abstract】 China is lack of forestry resources. With rapid development of economy and enhancement of civilian living condition,the contradiction between need and supply has become prominent. Making full development of fast-grown forest is a efficient measure to deduce the contrary and a important form to resolve the shortage of wood sources. Our country is rich in poplar,which can be used as the raw material of wood-based panel. It can relieve the contrary between need and supply effectively.However,fast-grown poplar is soft and of low density, limiting the use scope of poplar plywood. Besides, although soybean glue has many advantages such as cheap, abundant, recyclable, facilitative, harmless and lasting, it can’t reach the standard of GBⅡplywood as its bad waterproof capacity, low bonding strength and easy-to-be-decomposed character. As a result, the purpose of this paper is to improve the properties of poplar soybean adhesive plywood and UF resin plywood by micro/macro fibrils, making them available to more applications.In this paper,poplar pulp is processed to nano-fiber with ultrasonic crusher. Furthermore, the properties of morphology,molecular weight and crystal ratio were analyzed with electron microscope,granularity distributing machine and X-ray diffractor.FTIR,DSC,DMA is applied to analyze the influence of poplar macro/nano fibrils on soybean glue. The DMA figures of soybean glue illustrates that poplar macro/nano fibrils improve the elastic variety resistence of soybean glue.The curing reaction mechanism of UF and MF resin is analyzed to presume the influence of poplar macro/nano fibrils on UF and MF adhesive.To improve the adhesive strength of poplar plywood,add 1%-5% nano-fibre to soybean glue poplar plywood separately as reinforcement,and then spread glue on veneer on the amount of 480 g/m2. Hot press in the condition of 160℃,80 s/mm and 1.6 Mpa. It explicates soybean glue plywood with 3% nano-fibre addition performs highest adhesive strength,increasing by 56% in the strength than soybean glue plywood without nano-fibre. Add 1%-10% nano-fibre of spreading glue amount to urea-formaldehyde resin plywood to improve its adhesive properties. The parameter is as following:double-face spreading amount 280 g/m2,pressure 1.2Mpa,temperature 110 -120C,time 1-1.5min/mm. The adhesive strength raise with the increase of nano-fibre amount,and performs better.Add 1%-5% nano-fibre of spreading glue amount to MF adhesive,which is spread on the surface of plywood to improve the exterior performance of poplar plywood. Brushed MF with 3% and 5% nano-fibre,the color firmness of the veneer is improved prominently,20% higher than veneer brushed with blank MF. Adding nano-fiber can enhance surface abrading persistence distinctively,while 1% nano-fibre addition performs best.更多还原