Synthesis and properties of ceramic - Polymer composits

The microwave plasma process is capable to produce nanoparticulate powders with mean particle sizes in the range from 5 to 20 nm. The products may be oxides, nitrides, sulphides, selenides, or even metals. Additional, it is p ossible to coat these particles with a layer of a second ceramic or a polym er. The powder with the polymer coating can be densified by hot pressing at 100 degrees C. The resulting body may be used because of their special opt ical or magnetic properties. As an example of application the synthesis and the magnetic properties of a composite consisting of gamma-Fe2O3 as kernel and PMA as coating are given. The resulting material is superparamagnetic. This is demonstrated by the magnetisation curves and Mossbauer spectroscop y. (C) 1999 Acta Metallurgica Inc.