ABSTRACT

Finger-joint is a technological process that uses small-dimension and low-quality lumber to obtain high-quality structural wood products. Curing time of an adhesive consists one of the most important factors on the final performance of finger-jointed wood. In this study, finger-jointed black pine (Pinus nigra L.) specimens were prepared to investigate the effect of finger length and adhesive type on the curing time of these assemblies, as specified by their static flexural properties. Two adhesive types (an emulsion polymer isocyanate and melamine-urea-formaldehyde adhesives), two finger lengths (12.5 and 20.0 mm) and four curing times (2.5, 7, 24 and 168 h) were used for this purpose. Statistical analysis results showed that finger length and curing time had a statistically influence on the bending behaviour of single finger-joint specimens. The necessary handling strength was attained between 7 and 24 h for the 12.5 mm specimens, while the 20.0 mm length finger-joints could be further processed after 2.5 h.

摘要

指接是一种利用小尺寸、劣质木材获得优质结构木制品的工艺流程。粘合剂的固化时间是影响指接木材最终性能的最重要因素之一。在这项研究中，指接黑松（Pinus nigraL.) 准备样品以研究手指长度和粘合剂类型对这些组件固化时间的影响，这些组件的固化时间由它们的静态弯曲特性指定。为此使用了两种粘合剂类型（乳液聚合物异氰酸酯和三聚氰胺-脲-甲醛粘合剂）、两种手指长度（12.5 和 20.0 毫米）和四个固化时间（2.5、7、24 和 168 小时）。统计分析结果表明，手指长度和固化时间对单指关节试样的弯曲行为有统计学影响。对于 12.5 毫米的试样，在 7 到 24 小时之间获得了必要的处理强度，而 20.0 毫米长的指关节可以在 2.5 小时后进一步加工。