摘要 |
The present invention relates to a procatalyst composition for the polymerization of alpha-olefines, which has been prepared in steps, in which is arranged a carrier agent based on at least one inorganic oxide, having few or no hydroxyl groups on its surface, and the carier agent is reacted with the magnesium compound and one or more transition metal compounds of the groups IVB and VB of the periodic table. It has been observed that such a catalyst is most-advantageous when a) this carrier agent is impregnated with a mixture of the Mg compound and one or more compounds of a transition metal of the groups IVb or Vb of the periodic table, which dissolves the Mg compound, and b) by chlorinating with a compound that does not contain titanium so that 1) the carrier is first treated with a mixture in the form of a solution of the Mg compound and the transition metal compound and the product thus obtained is chlorinated, or 2) the carrier is first chlorinated and subsequently treated with the above mixture in the form of a solution, or 3) the Mg compound and the transition metal compound are impregnated into the carrier without any separate dissolving and the product thus obtained is chlorinated.
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