Methods for controlling dual catalyst olefin polymerizations with an alcohol compound
AssigneeChevron Phillips Chemical Company LP
InventorsQing Yang, Max P. McDaniel, Tony R. Crain, Albert P. Masino, Ted H. Cymbaluk, John D. Stewart
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Abstract
Methods for controlling properties of an olefin polymer using an alcohol compound are disclosed. The MI and the HLMI of the polymer can be decreased, and the Mw and the Mz of the polymer can be increased, via the addition of the alcohol compound.
Claims20
A method of controlling a polymerization reaction in a polymerization reactor system, the method comprising:
- (i) contacting a dual catalyst system with an olefin monomer and an optional olefin comonomer in the polymerization reactor system under polymerization conditions to produce an olefin polymer,
- wherein the dual catalyst system comprises a first metallocene catalyst component, a second metallocene catalyst component, an activator, and a co-catalyst;
- and
- (ii) introducing an amount of an alcohol compound into the polymerization reactor system to (I) reduce a melt index parameter of the olefin polymer;
- (II) increase a molecular weight parameter of the olefin polymer selected from Mw, Mz, or both;
- or (III) reduce a melt index parameter of the olefin polymer and increase a molecular weight parameter of the olefin polymer selected from Mw, Mz, or both.
A process for producing an olefin polymer with a target melt index parameter, a target molecular weight parameter, or a target melt index parameter and a target molecular weight parameter, the process comprising:
- (a) contacting a dual catalyst system with an olefin monomer and an optional olefin comonomer in a polymerization reactor system under polymerization conditions,
- wherein the dual catalyst system comprises a first metallocene catalyst component, a second metallocene catalyst component, an activator, and a co-catalyst;
- and
- (b) controlling an amount of an alcohol compound introduced into the polymerization reactor system to produce the olefin polymer with the target melt index parameter, the target molecular weight parameter, or the target melt index parameter and the target molecular weight parameter;
- wherein:
- the melt index parameter is MI, HLMI, or both;
- and
- the molecular weight parameter is Mw, Mz, or both.
Dependencies are inferred from the claim text.