氯丁橡胶胶黏剂对多层胶合板韧性的影响

摘要

The impact toughness of multi-layer plywood was improved by the mixtures of urea formaldehyde resin ( UF) and chloroprene rubber adhesive ( CR) in wood industry. The effects of the ratio of CR to UF (0/6, 1/5, and 2/4) , lay-up structure (UF313, CR151, and UF511) and load direction (UF61 , CR16, UF511, and CR115 ) on the mechanical properties were studied. Results showed that the impact strength of multi-layer plywood increased with increasing content of CR, while the emission of formaldehyde from plywood reduced. However, the addition of CR could decrease the bonding strength and bending properties. The multi-layer plywood had the optimum mechanical strength when CR was applied to tensile load, and UF to compress load.%采用木材工业常用的脲醛树脂(UF)胶黏剂和氯丁橡胶(CR)胶黏剂复合压制多层胶合板,用以改善胶合板的冲击韧性.主要探讨在7层胶合板中不同的CR与UF比例(CR、UF胶层比分别为0/6,1/5和2/4),相同CR与UF比例时(2/4),CR胶在板材结构中所处位置的不同(UF313,CR151和UF511)以及不同受力状态(UF61和CR16,UF511和CR115)等对多层胶合板性能的影响.结果表明:使用CR胶可以提高胶合板的冲击强度,同时能降低板材的甲醛释放量,且CR胶用量越大,板材的冲击强度越高,甲醛释放量越低,但对板材的胶合强度和弯曲性能则有负面影响.将CR胶层侧作为板材的拉伸面,UF胶层侧作为受压面,有利于充分发挥两种胶黏剂各自的优势,使复合板材的性能达到最佳.