【摘要】 以表面含有氨基的可反应性纳米SiO2(RNS-A)和表面含有烷基碳链的可分散性纳米SiO2(DNS-3)作为填料,利用原位聚合法制备了尼龙6/SiO2纳米复合材料(相应的复合材料分别简记为RPA和DP3);采用透射电子显微镜观察了复合材料中纳米SiO2的表面形貌,并利用热失重分析仪测定了复合材料的热稳定性,进而考察了纳米SiO2表面功能基团对尼龙6力学性能和热稳定性的影响.结果显示,纳米SiO2能够很好地分散在尼龙6基体中,并使尼龙6的热分解温度提高10℃左右.与此同时,RPA的最大拉伸强度和冲击强度较纯尼龙6的分别提高34.5%和12.5%,DP3的最大拉伸强度和冲击强度分别提高18.2%和45.7%.这表明两种纳米SiO2均可以有效地提高尼龙6的力学性能和热稳定性;可以推测,纳米SiO2的增强效应与其在尼龙6基体材料中的分散和界面作用有关.更多还原

【Abstract】 Nylon 6/SiO2nanocomposites(denoted as RPA and DP3)were prepared by in situ polymerization method with reactable nano-SiO2 containing active amino group(denoted as RNS-A)and dispersible nano-SiO2 containing alkyl carbon chain(denoted as DNS-3)as the fillers.The surface morphology of as-prepared composites was observed with a transmission electron microscope,and their thermal stability was evaluated by thermogravimetric analysis.Furthermore,the effects of surface functional groups of nano-SiO2 on the mechanical properties and thermal stability of nylon-6matrix were investigated.Results indicate that the two kinds of nano-SiO2 can be uniformly dispersed in nylon 6matrix and increase the thermal decomposition temperature of nylon 6by about 10℃.In the meantime,the maximum tensile strength and impact toughness of as-prepared RPA composite are higher than that of neat nylon 6by 34.5%and 12.5%,while those of DP3 composite increase by 18.2%and 45.7%as compared with the polymer matrix.This demonstrates that both RNS-A and DP3 can effectively improve the mechanical properties and thermal stability of nylon 6,which could be closely related to their dispersion in the polymeric matrix and the interfacial effect as well.更多还原