SURFACE-MODIFIED SUPERPARAMAGNETIC OXIDIC PARTICLES

摘要

Surface-modified superparamagnetic oxidic particles, characterized by the following physicochemical characteristics : BET surface area 20 to 75 m2/g; Carbon content 0.5 to 6.0% by weight; Tamped density 150 to 500 g/1; Chlorine content 50 to 1000 ppm; Drying loss 0.1 to 4.0% by weight are prepared by contacting the oxides with the surface modifier either by spraying or vapour deposition and then heat-treating them. The surface-modified oxidic particles can be used as a filler in adhesives. Further fields of application are use for data carriers, as a contrast agent in imaging processes, for biochemical separation and analysis processes, for medical applications, as an abrasive, as a catalyst or as a catalyst support, as a thickener, for thermal insulation, as a dispersing assistant, as a flow assistant and in ferrofluids.