为提高MC尼龙的综合性能,采用KH-550硅烷偶联剂处理纳米SiO2,根据阴离子聚合反应制备MC尼龙SiO2纳米复合材料,探讨了表面处理纳米SiO2与熔体的作用机理,并进行复合材料的结构表征与性能测试.研究表明：纳米SiO2表面包覆硅烷偶联剂,其有机官能团氨基进攻聚合反应体系中酰亚胺结构的羰基,两者通过化学键实现界面结合;纳米SiO2粒子均匀分散在尼龙基体中,对尼龙6的结晶过程起到异相成核作用;当复合材料受到外力时,纳米粒子通过界面作用带动基体产生屈服耗散能量,阻碍裂纹扩展,实现增强增韧作用;纳米SiO2质量分数为1%时复合材料的力学性能最优.%To improve the comprehensive properties of MC nylon,nano-silica particles were pretreated with silane coupling agents KH-550,and silica reinforced monomer casting nylon composites were successfully prepared by anionic polymerization of ε-caprolactam.The structure and properties of MC nylon composites were investigated in detail.The results showed that lots of macromolecule chains with imide group were produced after sodium hydroxide was added into polymerization reaction system.The amido of silane coupling agent grafted on nana-silica particles could attack carbonyl group of imido group during polymerization reaction so that strong chemical bonds combined nano-silica and nylon matrix.The nano-silica particles were dispersed uniformly in nylon matrix.They played the role of heterogeneous nucleating agents,improved the crystallization rate of matrix,served as chemical cross-link points in the composite,droved matrix yield through interfacial interaction thus blocking tiny crack spreading and absorbed more energy.The optimum comprehensive mechanical properties could be achieved in case of the composite containing 1wt% silica.
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