Fe3O4/PMMA纳米复合材料的制备及其磁流变性能

The preparation and magnetorheological characterization of Fe3O4/PMMA composite particles

采用水热法以简单原料一步合成出Fe3O4/PMMA纳米复合材料，由于聚甲基丙烯酸甲酯（PMMA）的作用，Fe3O4由十几纳米部分聚集形成几百纳米的粒子，并在PMMA中分散较为均匀．复合粒子具有较高的饱和磁化强度，为超顺磁性。由合成的复合粒子制备得到的磁流变液具有较高的剪切屈服应力和储能模量，分别可达十几kPa和几MPa，其值随外加磁场的增大而增大。

Fe3O4/PMMA nano composite particles were fabricated successfully by one-pot hydrothermal method using simple raw materials. About ten nanometers Fe3O4 assembled to hundreds nanometers big particles through poly methyl methacrylate （PMMA）, and dispersed uniformly in it. The composite particles display a higher saturated magnetization and superparamagnetic property. In addition, the magnetorheological fluids （MRFs） prepared with our composite particles has much higher shear yield stress and storage modulus which reached to several kPa and MPa respectively, and become much bigger along with the increase of magnetic field.