【摘要】 用溶胶-凝胶法制备了表面含可聚合官能团的亚微米SiO2粒子,利用在其表面的乳液聚合成功制备了具有核-壳结构的SiO2-聚甲基丙烯酸甲酯(PMMA)-甲基丙烯酸缩水甘油酯(GMA)复合粒子,通过TEM、FTIR和TGA对其结构进行了表征;然后制备了SiO2-PMMA-GMA/环氧树脂复合材料,利用SEM观察其断裂形貌,并分析了复合粒子增韧环氧树脂的机制。结果表明:SiO2为复合粒子的内核,粒径约为180nm,其表面被PMMA-GMA聚合物包覆,厚度约为20nm;PMMA-GMA聚合物与SiO2的质量比为87.4%,PMMA-GMA聚合物对SiO2的接枝率及PMMA-GMA聚合物的有效接枝率分别为77.0%和88.1%;当SiO2-PMMA-GMA复合粒子在环氧树脂中的含量为4wt%时,其固化后的冲击强度可由19.2kJ/m2增加到42.0kJ/m2。更多还原

【Abstract】 Based on the sol-gel method,the submicron SiO2 particles with the polymerizable group on the surface were prepared.The SiO2-poly(methyl methacrylate)(PMMA)-glycidyl methacrylate(GMA)composite particles with the core-shell structure were successfully prepared by emulsion polymerization on the surface of SiO2,the structure of the composite particles was characterized by TEM,FTIR and TGA.In succession,the SiO2-PMMAGMA/epoxy composite materials were prepared and SEM was used to observe the fracture morphology,then the toughness mechanism of composite particles to epoxy was also put forward.The results indicate that SiO2 is the core in the composite particles with about 180 nm diameter,the surface of SiO2 is encapsulated by PMMA-GMA polymer with about 20 nm thickness.The mass ratio of PMMA-GMA polymer to original SiO2 is 87.4%,the grafting ratio of PMMA-GMA polymer to original SiO2 and effective grafting ratio of PMMA-GMA polymer are 77.0%and 88.1%,respectively.The impact strength of epoxy after curing increases to 42.0kJ/m2 from 19.2kJ/m2 when the content of the SiO2-PMMA-GMA composite particles is 4wt%in the epoxy matrix.更多还原