Abstract:

To improve the structure and properties of the cation-modified ferric oxide in air atmosphere, the preparation process of polydiallyldimethylammonium chloride (PDDA) modified ferric oxideis further optimized. Ferric oxide was prepared by chemical co-precipitation, and was modified with PDDA at different grain forming stages, and the influence of modification on the product quality was investigated. The prepared modified ferric oxide was characterized and tested by of X-ray diffraction, particle size analyzer, transmission electron microscopy and vibrating sample magnetometer. The result shows that the modification is carried out directly after the formation of crystalline iron oxide. The coating thickness is suitable and the coating ratio is 2.01%. The ferric oxide nanoparticles are uniformly dispersed in the PDDA. The magnetic properties of composite particles are strongest up to 3.47×10⁵ A/m.

Key words: ferric oxide, poly diallyl dimethyl ammonium chloride, cationic modification, structure and property