通过氢氧化铝和十二烷基苯磺酸钠(SDBS)对纳米SiO2进行表面包覆和改性处理,改善纳米SiO2的表面结构和分散性。使用IR、FESEM、EDS、Malvem Zetasize 3000HSA自动电位粒度仪等表征手段,对表面包覆改性后纳米SiO2的表面结构、形貌及等电点等进行了测试和分析。结果表明,经Al(OH)3表面包覆后,纳米SiO2粉体等电点(IPE)的pH值从1.58变为7.1;经SDBS对表面包覆Al(OH)3的纳米SiO2进行改性后,纳米SiO2粉体团聚现象减少,单个纳米SiO2颗粒的粒径约为30nm。
Nano-SiO2 are uniformly coated with Al(OH)3, and then modified by neopelex, and this method can improve the surface structure and dispersibility. The surface structure, and isoelectric point of specimens are characterized by IR, FESEM, EDS and Malvern Instruments Zetasizer systems. The results show that the IPE of as-received SiO2 is pH 1.58, that of Al(OH)3-coated SiO2 shifts to pH 7.1. After surface modification by SDBS, the aggregate phenomenon of nano-SiO2 particle is reduced, the grain size of single SiO2 particle is about 30nm.