Abstract: The present invention provides polymerization catalyst compounds, catalyst systems including these catalyst compounds, and to their use in the polymerization of ethylene and at least one comonomer. In particular, the invention provides a catalyst system comprising a poor comonomer incorporating catalyst compound and a good comonomer incorporating catalyst compound. Preferably, the low comonomer incorporating catalyst compound is a metallocene containing at least one substituted or unsubstituted fused ring cyclopentadienyl based ligand which is substantially directed to the front of the molecule, contains a long bridging group, or which contains a methyl substitution pattern which correlates to poor comonomer incorporation. The invention also provides methods of selecting the poor comonomer incorporating metallocene to pair with the good comonomer incorporating metallocene to produce polymers that are easy to process into a variety of articles, especially polyethylene based film, having enhanced properties.

Abstract: Blends of very low density polyethylene produced using metallocene catalysts (mVLDPE) and high density polyethylene (HDPE) are disclosed. The polymer blends include a metallocene-catalyzed VLDPE polymer having a density of less than 0.916 g/cm3, the VLDPE polymer preferably being linear and without long chain branching, and a HDPE polymer having a density of greater than 0.940 g/cm3. The polymer blends are particularly suitable in blown and cast film applications.

Abstract: Linear low density polyethylenes (LLDPEs) that have relatively high melt index ratios (MIR) and relatively high melt strength (MS) are described. This combination of melt properties is achieved by a substantially non-blended LLDPE. Catalysts used to produce these polyethylenes are generally a blend of bridged bisindenyl zirconocene dichlorides, where one zirconocene contains saturated indenyls and the other unsaturated indenyls.

Abstract: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: Bimetallic catalyst for producing polyethylene resins with a bimodal molecular weight distribution, its preparation and use. The catalyst is obtainable by a process which includes contacting a support material with an organomagnesium component and carbonyl-containing component. The support material so treated is contacted with a non-metallocene transition metal component to obtain a catalyst intermediate, the latter being contacted with an aluminoxane component and a metallocene component, This catalyst may be further activated with, e.g., alkylaluminum cocatalyst, and contacted, under polymerization conditions, with ethylene and optionally one or more comonomers, to produce ethylene homo- or copolymers with a bimodal molecular weight distribution and improved resin swell properties in a single reactor. These ethylene polymers are particularly suitable for blow molding applications.

Abstract: A family of novel hetrocyclic-amide type catalyst precursors useful for the polymerization of olefins, such as ethylene, higher alpha-olefins, dienes, and mixtures thereof.

Abstract: Blends of very low density polyethylene produced using metallocene catalysts (mVLDPE) and linear low density polyethylene (LLDPE) are disclosed. The polymer blends include a metallocene-catalyzed VLDPE polymer having a density of less than 0.916 g/cm3, the VLDPE polymer preferably being linear and without long chain branching, and a LLDPE polymer having a density of from 0.916 to 0.940 g/cm3. The polymer blends are particularly suitable in blown and cast film applications.

Abstract: The present invention relates to a continuous gas phase process comprising polymerizing one or more hydrocarbon monomer(s) in a fluidized bed reactor in the presence of catalyst system or polymerization catalyst and a condensable fluid for a period of at least 12 hours where the bed temperature is less than the Critical Temperature and the dew point temperature of the gas composition in the reactor is within 25° C. of the bed temperature.

Abstract: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: A method of polymerizing olefins comprising combining in one embodiment ethylene and optionally one or more ?-olefins with a catalyst composition in a continuous polymerization reactor at a pressure of less than 10,000 kPa; wherein the catalyst composition comprises a hafnocene; and isolating a polyethylene having a density in the range of from 0.930 to 0.975 g/cm3. Also provided is a method of transitioning a continuous polymerization reactor from production of a low density polyethylene to a medium or high density polyethylene. Also provided is a medium to high density polyethylene suitable for injection or rotomolding applications. Also provided is a single catalyst composition suitable for such needs.

Abstract: Disclosed are methods of producing di-, tri- or tetrabenzyl-metal compounds comprising combining a metal salt with a (benzyl)nMgX2-n compound at from less than 30° C., wherein n is 1 or 2 and X is a monoanionic group; wherein the combining takes place in a diluent mixture comprising from 0 to 80% by volume of an ether diluent and a diluent selected from the group consisting of aromatic diluents, halogenated hydrocarbon diluents, and mixtures thereof. The methods are characterized by employing various mixtures of diluents, and in some cases, minimal to no ether diluent.

Abstract: The present invention provides polymerization catalyst compounds, catalyst systems including these catalyst compounds, and to their use in the polymerization of ethylene and at least one comonomer. In particular, the invention relates to identifying the comonomer incorporation behavior of metallocene polymerization catalyst compounds. More particularly, the invention relates to identifying metallocene catalyst compounds which incorporate comonomer poorly. Preferably, such metallocene catalyst compounds contain at least one substituted or unsubstituted fused ring cyclopentadienyl based ligand. The invention also relates to the use of these low comonomer incorporating metallocene catalyst compounds in catalyst systems to produce polymers that are easy to process into a variety of articles, especially polyethylene based film, having enhanced properties.

Abstract: Novel catalyst monoamide precursor compositions and the corresponding single site-like catalysts for olefin polymerization.

Abstract: The present invention relates to a catalyst composition and a method for making the catalyst composition which comprises a polymerization catalyst and at least one gelling agent. The invention is also directed to the use of the catalyst composition in the polymerization of olefin(s). In particular, the polymerization catalyst system is supported on a carrier.

Abstract: Films and methods of forming films comprising first combining in a reactor olefins, a catalyst composition and an activator; wherein the activator is present from less than 50 wt % in a diluent by weight of the activator and diluent; followed by isolating a polyolefin having a density of from 0.940 to 0.980 g/cm3; and finally, extruding the polyolefin into a film having a gel count of less than 200 gels/m2.

Abstract: Methods of preparing bimetallic catalysts are disclosed. The methods include the steps of providing a supported non-metallocene catalyst, contacting a slurry of the supported non-metallocene catalyst in a non-polar hydrocarbon with a solution of a metallocene compound and an alumoxane, and drying the contact product to obtain a supported bimetallic catalyst. The supported non-metallocene catalyst is prepared by dehydrating a particulate support material at a temperature of greater than 600° C., preparing a slurry of the dehydrated support in a non-polar hydrocarbon, contacting the slurry with an organomagnesium compound and an alcohol, contacting the resulting slurry with a non-metallocene compound of a Group 4 or Group 5 transition metal, and drying the contact product to obtain a supported non-metallocene catalyst as a free-flowing powder. The bimetallic catalysts show increased activity relative to catalysts prepared using support materials dehydrated at lower temperatures.

Abstract: Processes for transitioning among polymerization catalyst systems, preferably catalyst systems that are incompatible with each other. In particular, the processes relate to transitioning from olefin polymerizations utilizing metallocene catalyst systems to olefin polymerizations utilizing traditional Ziegler-Natta catalyst systems.

Abstract: A polymerization catalyst system and process, which utilizes a Group 14 and Group 16 containing non-crystalline compound to solubilize or emulsify polymerization catalyst components, is disclosed.

Abstract: The present invention is directed to the use of aluminum alkyl activators and co-catalysts to improve the performance of chromium-based catalysts. The aluminum alkyls allow for the variable control of polymer molecular weight, control of side branching while possessing desirable productivities, and may be applied to the catalyst directly or separately to the reactor. Adding the alkyl aluminum compound directly to the reactor (in-situ) eliminates induction times.