Filler, and process for the preparation thereof

摘要

The filler comprises silanised calcium sulphate anhydrite having a mean particle size of between 1 and 10 mu m, a maximum particle size of less than 30 mu m, preferably less than 20 mu m, obtainable from a sulphuric acid-moistened gypsum from flue gas desulphurisation. The filler is prepared by conventional silanisation of the anhydrite. It is particularly suitable for replacing talc in polypropylene-based plastics.