Ziegler-Natta catalyst with an electron donor compound for increasing polymer molecular weight

A process for preparing a heterogeneous procatalyst, the process comprising contacting a magnesium chloride component with a chlorinating agent, a titanium species, wherein the titanium species is TiCl4-c(OR3)c or TiCl3-d(OR3)d, wherein R3 is (C1-C20)hydrocarbyl, c is 0, 1, 2, 3, or 4, and d is 0, 1, 2, or 3;

• and a metal-ligand complex, wherein:
• the magnesium chloride component is a preformed MgCl2 support with specific surface area of at least 100 m2/g;
• the chlorinating agent has a structural formula Al(Cl)x(R1)3-x or Si(Cl)y(R1)4-y, where:
• R1 is a (C1-C30) hydrocarbyl;
• x is 1, 2, or 3;
• and
• y is 1, 2, 3, or 4;
• and
• the metal-ligand complex has a structural formula (L)nM(Y)m(XR2)b, where:
• M is a metal cation;
• each L is a neutral ligand or (═O);
• each Y is a halide or (C1-C20)alkyl;
• each XR2 is an anionic ligand in which X is a heteroatom or a heteroatom-containing functional group and R2 is (C1-C20)hydrocarbyl or (C1-C20)heterohydrocarbyl;
• n is 0, 1, or 2;
• m is 0, 1, 2, 3, or 4;
• b is 1, 2, 3, 4, 5, or 6;
• and
• the metal-ligand complex is overall charge neutral;
• wherein the molar ratio of the total amount of chlorine in the chlorinating agent to the sum of the amounts of OR3 and XR2 in the heterogeneous procatalyst is from 0.33 to 1.45.

A process of preparing a heterogeneous procatalyst, the process comprising contacting components (1) and (2) without further chlorination, wherein:

• component (1) is a preformed heterogeneous procatalyst comprising:
• a titanium species;
• and
• a MgCl2 support;
• and
• component (2) is a metal-ligand complex having a structural formula (L)nM(Y)m(XR2)b, where:
• M is a metal cation;
• each L is a neutral ligand or (═O);
• each Y is a halide or (C1-C20)alkyl;
• each XR2 is an anionic ligand in which X is a heteroatom or a heteroatom-containing functional group and R2 is (C1-C20)hydrocarbyl or (C1-C20)heterohydrocarbyl;
• n is 0, 1, or 2;
• m is 0, 1, 2, 3, or 4;
• b is 1, 2, 3, 4, 5, or 6;
• and
• the metal-ligand complex is overall charge neutral;
• wherein the metal-ligand complex comprises at least one of vanadium(V) oxytripropoxide, vanadium(V) oxytributoxide, vanadium(V) oxytriisopropoxide, titanium(IV) isopropoxide, or combinations thereof.