采用溶胶-凝胶法在经表面羟基活化处理的纳米Fe3O4颗粒表面包覆无定型态TiO2, 并用极性分子丙烯酰胺掺杂改性TiO2包覆层, 得到了Fe3O4/TiO2核壳复合微粒, 然后将其分散到甲基硅油中配制成复合微粒电流变液; 研究了复合微粒的物相和微观形貌, 以及电流变液的电流变性能。结果表明: TiO2能够均匀紧密地包覆于纳米Fe3O4颗粒表面, 并且包覆4次TiO2, 搅拌时间为4 h, 丙烯酰胺质量分数为25％时, 制得的复合微粒电流变液的电流变性能最好, 其剪切强度可达41.9 kPa。

Using sol-gel method to make the hydroxyl activated surface of nano Fe3O4 particles coated with amorphous TiO2, and the TiO2 coating layer was modified by doping polar molecular acrylamide to prepare Fe3O4/TiO2 core-shell composite particles. And then, the core-shell composite particles were distributed into methyl silicone oil to prepare composite particles electrorheological fluid. The phase and microstructure of composite particles, as well as the electrorheological characterization of electrorheological fluid were studied. The results show that TiO2 can be uniformly and intimately coated on the surface of nano Fe3O4 particles. When coating times were four, stirring time was 4 h, and mass fraction of acrylamide was 25wt%, the composite particles electrorheological fluide could obtained the best electrorheological characteristics, and its shear strength up to 41.9 kPa.