Ziegler-natta catalyst for polyolefins
A Ziegler-Natta type catalyst component can be produced by a process comprising contacting a magnesium dialkoxide compound with a halogenating agent to form a reaction product A, and contacting reaction product A with a first, second and third halogenating/titanating agents. Catalyst components, catalysts, catalyst systems, polyolefin, products made therewith, and methods of forming each are disclosed. The reaction products can be washed with a hydrocarbon solvent to reduce titanium species [Ti] content to less than about 100 mmol/L.
1. A process for making a catalyst component comprising:
a) generating a reaction product A by contacting a magnesium dialkoxide compound with a halogenating agent;
b) contacting reaction product A with a first halogenating/titanating agent to form reaction product B;
c) contacting reaction product B with a second halogenating/titanating agent to form reaction product C; and
d) contacting reaction product C with a third halogenating/titanating agent to form catalyst component D.
2. The process of claim 1 wherein the halogenating agent is of the general formula ClAR′″ x , wherein A is a nonreducing oxyphilic compound, R′″ is a hydrocarbyl moiety having from about 2 to 6 carbon atoms, and x is the valence of A minus 1.
3. The process of claim 1 wherein the halogenating agent is ClTi(O i Pr) 3 .
4. The process of claim 1 wherein the first halogentating/titanating agent is a blend of two tetra-substituted titanium compounds with all four substituents being the same and the substituents being a halide or an alkoxide or phenoxide with 2 to 10 carbon atoms.
5. The process of claim 4 wherein the first halogentating/titanating agent is a blend of a titanium halide and an organic titanate.
6. The process of claim 5 wherein the first halogentating/titanating agent is a blend of TiCl 4 and Ti(OBu) 4 in a range from 0.5:1 to 6:1 TiCl 4 /Ti(OBu) 4 .
7. The process of claim 1 wherein the second and third halogenating/titanating agents comprise titanium tetrachloride.
8. The process of claim 7 wherein steps c) and d) each comprise a titanium tetrachloride to magnesium ratio in the range of about 0.1 to about 5.
9. The process of claim 1 wherein reaction products A, B, and C are washed with a hydrocarbon solvent prior to subsequent halogenating/titanating steps.
10. The process of claim 9 wherein reaction products A, B, and C are washed with a hydrocarbon solvent until titanium species [Ti] content is less than about 100 mmol/L prior to subsequent halogenating/titanating steps.
11. The process of claim 1 wherein the reaction product D is washed with a hydrocarbon solvent until titanium species [Ti] content is less than about 20 mmol/L.
12. The process of claim 1 wherein an electron donor is present in any one or more of steps a), b), c), or d), and wherein the ratio of electron donor to metal is in the range of about 0:1 to about 10:1.
13. The process of claim 1 further comprising placing the catalyst of the invention on an inert support.
14. The process of claim 13 wherein the inert support is a magnesium compound.
15. The process of claim 1 further comprising: e) contacting D with an organometallic preactivating agent to form a preactivated catalyst system.