Hafnocene-titanocene catalyst system
AssigneeDow Global Technologies LLC
InventorsLinfeng Chen, David M. Pearson, Michael W. Tilston, Mridula Babli Kapur, Robert N. Reib, Stephanie M. Whited
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Abstract
A hafnocene-titanocene catalyst system comprising a hafnocene catalyst and a titanocene catalyst; polyolefins; methods of making and using same; and articles containing same.
Claims12
A hafnocene-titanocene catalyst system comprising a hafnocene catalyst and a titanocene catalyst, wherein the hafnocene catalyst comprises a product of an activation reaction of ((R1)x-cyclopentadienyl)((R2)y-cyclopentadienyl)hafnium dichloride/dibromide/dialkyl and an alkylaluminoxane, wherein subscript x is 1 or 2;
- subscript y is 0, 1 or 2;
- and each R1 and R2 independently is methyl, ethyl, a normal-(C3-C10)alkyl (linear), or an iso-(C3-C10)alkyl;
- and wherein the titanocene catalyst comprises a product of an activation reaction of bis(cyclopentadienyl)titanium dichloride with a trialkylaluminum;
- wherein the hafnocene-titanocene catalyst system is characterized by a trialkylaluminum/Hf molar ratio from 0.1 to 50 and a Ti/Hf molar ratio from 0.1 to 5.
A method of making a hafnocene-titanocene catalyst system, the method comprising contacting the ((R1)x-cyclopentadienyl)((R2)y-cyclopentadienyl)hafnium dichloride/dibromide/dialkyl with an alkylaluminoxane and, optionally, a carrier material to give hafnocene catalyst, and then contacting the hafnocene catalyst with a titanocene catalyst made by an activation reaction of bis(cyclopentadienyl)titanium dichloride with a trialkylaluminum;
- thereby giving the titanium catalyst and the hafnocene-titanocene catalyst system.
Dependencies are inferred from the claim text.