| abstract |
A catalyst and a process for the preparation of homopolymers and copolymers of alpha monoolefins by means of a catalyst system comprising (1) a titanium halide of the formula n n TiCl.sub.3 m AlCl.sub.3 n n where m is a number from 0 to 0.5, (2) a coordination complexing agent, the use of which is optional, and (3) an appropriate conventional aluminum-alkyl, the titanium halide (1) and the complexing agent (2), if used, having been milled together before use, wherein the catalyst system employed contains, as a further component (4), a sterically unhindered phenolic compound. |