Methods of controlling ziegler-natta pre-catalyst particles formation and use for olefin polymerization

A solid pre-catalyst system comprising solid particles of a reaction product of a complex of Formula I with a halogenated compound or a mixture of halogenated compounds;

• wherein:
• XTiClp(OR1)4-p.YMg(OR2)q(OR3)t (I)
• a molar ratio of X to Y (X/Y) is from 0.2 to 5.0;
• p is 0 or 1;
• 0<q<2;
• 0<t<2;
• the sum of q and t is 2;
• R1, R2, and R3 are each independently a linear or branched alkyl, a linear or branched heteroalkyl, a cycloalkyl, a substituted cycloalkyl, a substituted heterocycloalkyl, a substituted aryl, or a (heteroaryl)alkyl;
• R2 is not the same as R3;
• and
• the solid particles exhibit a D50 from about 3 μm to about 12 μm.

A method of polymerizing or co-polymerizing an olefin monomer, the method comprising:

• contacting a solid pre-catalyst system comprising solid particles of a composite of a reaction product of a halogenated compound and a colloidal suspension of a complex of Formula I with a reducing agent, optionally a chain transfer agent, and the olefin monomer or monomers:
• XTiClp(OR1)4-p.YMg(OR2)q(OR3)t (I)
• wherein:
• a molar ratio of X to Y (X/Y) is from 0.2 to 5.0;
• p is 0 or 1;
• 0<q<2;
• 0<t<2;
• the sum of q and t is 2;
• R1, R2, and R3 are each independently a linear or branched alkyl, a linear or branched heteroalkyl, a cycloalkyl, a substituted cycloalkyl, a substituted heterocycloalkyl, a substituted aryl, or a (heteroaryl)alkyl;
• R2 is not the same as R3;
• and
• the solid particles exhibit a D50 from about 3 μm to about 12 μm.