PROCESS FOR PREPARING A PROCATALYST COMPOSITION BY IMPREGNATION OF A CARRIER WITH A MAGNESIUM ALKOXIDE, A TITANIUM ALKOXIDE AND AN ALCOHOL SOLUTION

摘要

The present invention concerns a process for preparing a procatalyst composition suitable for the polymerization of ethene and other α-olefins, which comprises the steps of: (a) contacting an inorganic oxide carrier, having a low content of surface hydroxyls, with an impregnation solution containing a magnesium compound, an alcohol, and a tetravalent titanium compound, (b) chlorinating the contacted inorganic oxide carrier with a chlorinating agent, and (c) recovering the chlorination product to yield the procatalyst composition. Prior similar processes have the disadvantage of using polar solvents of low volatility and titanium tetrachloride as the source of active centers. Both materials make the process more difficult and contaminate its product. These problems have now been solved in such a manner that the impregnation solution comprises a magnesium alkoxide, a titanium alkoxide and a lower alcohol.