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提出了一种在室温、大气环境等温和条件下通过酯化反应将端羧基聚合物链接枝到纳米SiO2微球表面从而制备有机/无机复合纳米微粒的新方法.该方法通过以下两个步骤得以实现,即第一,用3-环氧丙基三甲氧基硅烷对纳米SiO2微球表面进行改性处理,接着将引入到纳米SiO2表面的环氧基团转化为烷羟基基团;第二,通过引入到纳米SiO2微球表面的烷羟基与聚合物中的端羧基在室温下发生酯化反应,从而将聚合物接枝到纳米SiO2表面制得复合微球.利用XPS、FTIR、TEM和TGA等测试手段对纳米SiO2的改性过程以及聚合物接枝后得到的复合微球进行了表征.研究结果表明,该室温酯化接枝方法具有较高的接枝率,接枝到无机纳米微粒表面的聚合物占复合微球质量的55wt%～70wt%;接枝聚合物后,纳米SiO2微球的粒径从40nm增加到64～75nm,从而得到了以SiO2为核、以聚合物为壳的有机-无机复合微球.
A new method for preparing organic / inorganic nanocomposites by grafting end-carboxyl polymer chains onto the surface of nanosilica microspheres through esterification under mild conditions such as room temperature and atmospheric environment was proposed in this paper, Firstly, the surface of nano-SiO2 microspheres was modified with 3-epoxypropyltrimethoxysilane, then the epoxy groups introduced onto the surface of nano-SiO2 were converted into the alkyl hydroxyl groups. Secondly, The microspheres were grafted onto the surface of nano-SiO2 by esterification reaction between the hydroxyl groups introduced into the surface of the nano-SiO2 microspheres and carboxyl groups in the polymer at room temperature. XPS, FTIR, TEM and TGA And other testing methods were used to characterize the modification process of nano-SiO2 and the composite microspheres obtained after polymer grafting.The results show that the room-temperature esterification grafting method has a higher grafting rate, grafted to inorganic nanoparticles The surface of the polymer composite microspheres accounted for 55wt% ~ 70wt%; after grafting the polymer, the particle size of the nano-SiO2 microspheres increased from 40nm to 64 ~ 75nm, resulting in SiO2 as the core, the polymer shell Organic-inorganic composite Ball.