异氰酸酯对竹材液化发泡材料性能的影响

以苯酚和聚乙二醇-400为液化剂合成竹材液化树脂，并加入表面活性剂、固化剂、发泡剂和异氰酸酯制备了竹材液化发泡材料。通过电子扫描显微镜和压缩强度、氧指数及耐候性等测试，分析了不同异氰酸酯添加量对竹材液化发泡材料结构与性能的影响。结果表明：随着异氰酸酯添加量的增加，材料泡孔结构更加均匀，材料压缩强度得到增强，最高可以达到0.399 MPa，材料的氧指数呈先增大后减小的趋势，最高可以达到48.8%。此外，材料中异氰酸酯使用量的增加，可降低材料的质量损失率，缩小材料压缩强度变化幅度，但是添加过量的异氰酸酯会导致材料变脆。
Liquefied bamboo resin was synthesized by using phenol and polyethylene glycol (PEG-400) as liquefied reagent. Liquefied bamboo foam (LBF) was then prepared by adding surface active agent, curing agent, foaming agent and isocyanate to the resin. The effects of isocyanate content on the structure and properties of LBF were studied by means of scanning electron microscopy (SEM) and tests of compressive strength, oxygen index and weatherability. The results showed that with the increasing of isocyanate content, the bubble structure of LBF became more uniform. The compressive strength increased to 0.399 MPa, the oxygen index first increased to 48.8% and then decreased, while the rate of mass loss was lowered and the compressive strength variation was narrowed. However, the excess of isocyanate addition will make the LBF become fragile