【作者】 任晓峰；

【导师】 申士杰；

【作者基本信息】 北京林业大学 ， 木材科学与技术， 2008， 硕士

【摘要】 研究开发结构用集成材是实现木材高效利用的一种非常有效的手段,对木材工业的发展具有重要推动作用。本论文对常温固化型胶粘剂间苯二酚PRF和高分子异氰酸酯API落叶松集成材的胶合工艺技术进行了研究。采用正交试验法考察了压力、涂胶量以及加压时间三个因子对集成材剪切强度、木破率和剥离率的影响,并且确定了最佳工艺参数。研究结果表明:间苯二酚和异氰酸酯胶粘剂集成材的顺纹剪切强度均可以达到GB/T 50329-2002的要求,剪切强度和木破率的关系满足ISO/DIS 12578的要求。根据JAS1152号和ISO/DIS 12580标准对两种胶粘剂集成材进行浸渍剥离、煮沸剥离和减压加压剥离试验,试验结果表明,PRF和API落叶松集成材的剥离率完全可以满足使用环境3和使用环境2的要求。按照EN301和JAS1152的要求,将间苯二酚胶粘剂划归为Ⅰ类胶粘剂,将异氰酸酯胶粘剂划归为Ⅱ类胶粘剂。对于间苯二酚胶粘剂集成材的胶合性能,加压时间的影响最显著;对于高分子异氰酸酯胶粘剂集成材的胶合性能,涂胶量的影响作为显著。作者还对PRF和API两种胶粘剂落叶松结构用集成材的各胶合性能指标:剪切强度、木破率和剥离率进行了对比研究,结果表明:前者优于后者。初步研究分析PRF和API胶粘剂和木材的界面胶合机理。借助接触角测定仪和扫描电子显微镜研究了胶粘剂在木材表面的润湿和渗透情况,分别从机械结合理论和化学键理论角度对其进行了分析与解释。更多还原

【Abstract】 The research and development of structural glulam plays an important role for the efficient utilization of wood and sustainable development of wood industry.This paper focuses on the research of bonding technology of Chinese Larch Glulam (glued-laminated timber) with Phenol resorcinol formaldehyde(PRF) and Aqueous polymer Isocyanate(API)adhesives.Orthogonal Experimental Method.is adopted to study the effect of pressure, glue spread and pressing time on the shear strength parallel to grain, Wood Failure Percentage(WFP)and delamination. The results indicate that shear strength of the two adhesives could meet the requirements of GB/T 50329-2002, and the relationship of shear strength and WFP meet that of ISO/DIS 12578. Water soak, water boiling and Vacuum-Pressure delamination testing methods are conducted according to JAS1152 and ISO/DIS 12580. It shows that PRF and API should be used for service class 3 as typeⅠand for service class 2 as typeⅡadhesive respectively based on EN301 and JAS1152 standard. Besides, pressing time and glue spread are the most influential factor respectively on the bonding property of PRF and API adhesives with Larch Glulam. Comparison analysis is made between PRF and API adhesives structural glulam regarding bonding properties in terms of shear strength, wood failure percentage and delamination. It indicates that PRF is superior to API.The bonding mechanism:of the two adhesives with Larch Glulam are analyzed by means of contact angle and Scanning Electron microscope to learn the wettablility and penetrability property of adhesives on wood surfaces, and explanation is given in terms of mechanic combination theory and chemical bond theory.更多还原