苎麻纤维增强原位阴离子聚合尼龙6复合材料的制备及性能研究

摘要

In this paper,textile-ramie fiber (RF) reinforced anionic polyamide-6 (APA6) composites were prepared successfully with the heat treated ramie fiber and caprolactam as monomer.The effects of the heat-treatment on the functional groups,the crystallization,the mechanical properties and the fracture morphology of the ramie fiber were studied.Meanwhile,the mechanical properties,thermal stability,as well as interfacial properties of the RF/APA6 composites were also investigated.The results showed that the hydroxyl groups covering on the ramie fiber surface decreased significantly,the crystallinity,the tensile strength and modulus decreased after the 280 ℃ heat-treatment,but no obvious changes in the morphology of the ramie fiber.The interfacial adhesion between the resin and the ramie fiber of the RF/APA6 composites was excellent.Compared with the neat APA6,the tensile strength of the composites increased slightly,while the tensile modulus,flexural property and the thermal stability were increased significantly.%以己内酰胺为单体,经热处理的苎麻纤维(RF)为增强材料,采用真空辅助树脂传递模塑成型工艺(VARTM)成功制备了苎麻纤维增强原位阴离子聚合尼龙6(APA6)复合材料.主要研究了热处理前后苎麻纤维表面官能团、结晶性能、力学性能和微观形貌的变化,并对复合材料的冲击断面、力学性能和热性能进行了考察.研究表明:当热处理温度为280℃时,苎麻纤维表面的羟基数量显著减少,结晶度略有降低,拉伸强度和模量有所下降,但苎麻纤维的形貌未有明显变化.RF/APA6复合材料中苎麻纤维与树脂的界面结合良好,与APA6相比,复合材料的拉伸强度略有提高,拉伸模量和弯曲性能得到明显提升,同时热稳定性显著提高.