Catalyst component for the preparation of nucleated polyolefins

Process for the production of a nucleated polypropylene composition, comprising:

• A) obtaining a catalyst composition containing a catalyst component through the steps of:
• a1) providing a solution of at least a Group 2 metal alkoxy compound (Ax) being the reaction product of a Group 2 metal compound (MC) and a monohydric alcohol (A) comprising in addition to the hydroxyl moiety at least one ether moiety optionally in an organic liquid reaction medium;
• or
• a2) providing a solution of at least a Group 2 metal alkoxy compound (Ax′) being the reaction product of a Group 2 metal compound (MC) and an alcohol mixture of the monohydric alcohol (A) and a monohydric alcohol (B) of formula ROH, optionally in an organic liquid reaction medium;
• or
• a3) providing a solution of a mixture of the Group 2 metal alkoxy compound (Ax) and a Group 2 metal alkoxy compound (Bx) being the reaction product of a Group 2 metal compound (MC) and the monohydric alcohol (B), optionally in an organic liquid reaction medium;
• or
• a4) providing a solution of Group 2 metal alkoxy compound of formula M(OR1)n(OR2)mX2−n−m or mixture of Group 2 alkoxides M(OR1)n′X2−n′ and M(OR2)m′X2−m′, where M is Group 2 metal, X is halogen, R1 and R2 are different alkyl groups of C2 to C16 carbon atoms, and 0<n<2, 0<m<2 and n+m+(2−n−m)=2, provided that both n and m≠0, 0<n′<2 and 0<m′<2;
• and
• b) adding said solution from step a1, a2, a3, or a4 to at least one compound (TC) of a transition metal of Group 4 to 6, and
• c) obtaining the solid catalyst component particles,
• d) washing said solidified particles,
• e) recovering the solidified particles of the olefin polymerisation catalyst component,
• wherein an electron donor is added at any step prior to step c) and is a non-phthalic internal electron donor,
• wherein the catalyst component is washed in step d) at least three times with at least one toluene and at least one TiCl4 washing step and 1 to 3 further washing steps with an aromatic and/or aliphatic hydrocarbon selected from toluene heptane, or pentane;
• wherein internal donor is added to either the toluene washing step and/or the TiCl4 washing step in an amount of 10 to 60 wt % of the total amount of donor used in catalyst preparation steps a) to d);
• wherein the catalyst component is further modified by a polymeric nucleating agent comprising vinyl compound units, and wherein the catalyst modification is performed until the concentration of unreacted vinyl compound is less than 0.1 wt %;
• and
• B) polymerizing propylene, optionally with co-monomers selected from C2 or C4 to C12 monomers in the presence of the catalyst composition obtained from step A), wherein the nucleated polypropylene composition comprises a polymeric nucleating agent in an amount in the range from 15 to 500 ppm.