Abstract: The present invention relates to a polymerization process using improved metallocene catalyst systems. Specifically, the catalyst systems of the present invention relate to a metallocene compound having optimized metals loading and activator concentration, and demonstrate improved operability and productivity. In an exemplary embodiment, the improved metallocene catalyst system of the present invention comprises a metallocene catalyst compound activated by methylaluminoxane, and a support material, the methylaluminoxane being present in the range of from 3 to 9 mmole methylaluminoxane per gram of support material, and the metallocene being present in the range of from 0.01 to 1.0 mmole metallocene per gram of support material.

Abstract: In some embodiments, a method in which at least one continuity additive (“CA”) and a seed bed are pre-loaded into a reactor, and a polymerization reaction is optionally then performed in the reactor. In other embodiments, at least one flow improver, at least one CA, and a seed bed are pre-loaded into a reactor. Pre-loading of a reactor with a CA can significantly improve continuity of a subsequent polymerization reaction in the reactor during its initial stages, including by reducing sheeting and fouling. The CA can be pre-loaded in dry form (e.g., as a powder), or in liquid or slurry form (e.g., as an oil slurry). To aid delivery of a dry CA to the reactor and combination of the dry CA with a seed bed in the reactor, the dry CA can be combined with a flow improver and the combination of CA and flow improver then loaded into the reactor.

Abstract: A supported catalyst composition having improved flow properties is disclosed comprising an alkylalumoxane, a metallocene-alkyl an inorganic oxide support having an average particle size of from 0.1 to 50 ?m and calcined at a temperature greater than 600° C., and optionally an antifoulant agent and. In one embodiment, the metallocene-alkyl is a Group 4, 5 or 6 metallocene-alkyl, and in another embodiment is a hafnocene-alkyl. Also disclosed is a method of polymerization using such a supported catalyst composition.

Abstract: Embodiments of our invention relate to processes for transitioning among polymerization catalyst systems including processes for transitioning among olefin polymerization reactions using Ziegler-Natta catalysts systems and chromium-based catalyst systems. Among embodiments contemplated are a method of transitioning from a first catalyst to a second catalyst in an olefin polymerization reactor, comprising: adding to the reactor a deactivating agent (DA) selected from one of carbon monoxide, carbon dioxide, or combinations thereof; adding to the reactor a cocatalyst adsorbing agent (CAA), comprising an inorganic oxide selected from one of silica, alumina or combinations thereof; wherein the first catalyst comprises at least one conventional Ziegler-Natta catalyst, and a cocatalyst, wherein the second catalyst comprises at least one chromium-based catalyst, wherein the reactor is a gas-phase, fluidized bed reactor, and wherein the CAA is substantially free of transition metals.

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: 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: 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: Embodiments of the present invention relate to measuring and controlling static in a gas phase reactor polymerization. In particular, embodiments relate to monitoring carryover static in an entrainment zone during gas phase polymerization to determine the onset of reactor discontinuity events such as chunking and sheeting. Embodiments also relate to monitoring carryover static to determine the need for effective additions of continuity additives that minimize reactor static activity and thereby preventing discontinuity events.

Abstract: A method of producing a polymerization catalyst component suitable for use in the polymerization of alpha-olefins, which method comprises forming an active component by co-comminuting an inorganic Lewis acid, a first organic electron donor, a support base selected from the group consisting of the Group IIA & IIIA salts and the salts of the multivalent metals of the first transition series with the exception of copper, and a polymerization active tri-, tetra-, or penta- valent transition metal compound of a Group IVB-VIB metal, and heating the active component in an inert hydrocarbon solvent to produce the polymerization catalyst component. The active component can be heated in the inert hydrocarbon solvent in the presence of an additional polymerization active tri-, tetra-, or penta- valent transition metal compound of a group IVB-VIB metal. In addition, a second organic electron donor may be incorporated in the active component.

Abstract: A method of producing a polymerization catalyst component suitable for use in the polymerization of alpha-olefins, which method comprises forming an active component by co-comminuting an inorganic Lewis acid, a first organic electron donor, a support base selected from the group consisting of the Group IIA and IIIA salts and the salts of the multivalent metals of the first transition series with the exception of copper, and a polymerization active tri-, tetra-, or penta- valent transition metal compound of a Group IVB-VIB metal, and heating the active component in an inert hydrocarbon solvent to produce the polymerization catalyst component. The active component can be heated in the inert hydrocarbon solvent in the presence of an additional polymerization active tri-, tetra-, or penta- valent transition metal compound of a group IVB-VIB metal. In addition, a second organic electron donor may be incorporated in the active component.

Abstract: A storage stable, improved catalyst is obtained when an aluminum-reduced titanium trichloride catalyst which has been modified by treatment with an electron donor is heated at a temperature and for a period of time sufficient to drive the reaction to completion. In some instances this will involve the removal of gas which has been generated during the modification. In the usual practice a temperature of about 90.degree. C. and a period of about 90 minutes will be employed.