Abstract: A process for polymerizing ethylene in the presence of a polymerization catalyst by copolymerizing ethylene with a comonomer selected from the group of C4-C10 alpha-olefins in three polymerization stages. The polymers produced in the three stages have different melt flow rates. The polymer composition produced by the process has good mechanical properties and can be used for making pipes. The process has a good productivity and provides a stable and economic operation.

Abstract: A process for polymerizing ethylene in the presence of a polymerization catalyst by copolymerizing ethylene with a comonomer selected from the group of C4-C10 alpha-olefins in three polymerization stages. The polymers produced in the three stages have different melt flow rates. The polymer composition produced by the process has good mechanical properties and can be used for making pipes. The process has a good productivity and provides a stable and economic operation.

Abstract: Polyethylene films having a good balance of optical and mechanical properties are disclosed. The films are derived from ethylene copolymer compositions made with a suitably substituted phosphinimine catalyst. The ethylene copolymers have very narrow molecular weight distributions and broadened comonomer distributions.

Abstract: Supported catalyst system for the polymerization of olefins, having at least two different monocyclopentadienyl transition metal compounds, one or more activators including an ionic compound having (i) a cation and (ii) an anion having up to 100 non-hydrogen atoms and the anion containing at least one substituent comprising a moiety having an active hydrogen, and one or more support materials. The supported “mixed or dual site” catalyst systems having different monocyclopentadienyl catalysts when activated by specific ionic activators lead to catalyst systems showing an improved balance of properties which may be used to prepare LLDPE polymers having broad melt flow ratios.

Abstract: Polyethylene films having a good balance of optical and mechanical properties are disclosed. The films are derived from ethylene copolymer compositions made with a suitably substituted phosphinimine catalyst. The ethylene copolymers have very narrow molecular weight distributions and broadened comonomer distributions.

Abstract: A supported catalyst for olefin polymerization comprises a selected ionic activator, a selected organometallic catalyst and a support material. The selected activator must contain an active hydrogen moeity. The organometallic catalyst is characterized by having a phosphinimine ligand and a substituted cyclopentadienyl ligand (which contains from 7 to 30 carbon atoms). The supported catalyst exhibits excellent activity in gas phase olefin polymerizations and may be used under substantially “non-fouling” polymerization conditions.

Abstract: The use of high activity “Single Site” polymerization catalysts often causes the fouling of polymerization reactors. The problem is particularly acute with gas phase polymerizations. While not wishing to be bound by theory it is believed that the fouling is initiated by the buildup of static charges in the reactor. The use of anti-static agents mitigates this problem, but typical antistatic agents contain polar species, which can deactivate the polymerization catalyst. We have now discovered that the use of a porous metal oxide support allows large levels of a selected antistatic agent to be used in a manner that reduces static/fouling problems in highly active polymerization catalysts.

Abstract: Supported catalyst systems for the polymerisation of olefins, comprise (a) at least two different monocyclopentadienyl transition metal compounds, (b) one or more activators comprising an ionic compound comprising (i) a cation and (ii) an anion having up to 100 non-hydrogen atoms and the anion containing at least one substituent comprising a moiety having an active hydrogen, and (c) one or more support materials. The, supported “mixed or dual site” catalyst systems comprising different monocyclopentadienyl catalysts when activated by specific ionic activators lead to catalyst systems showing an improved balance of properties which may be used to prepare LLDPE polymers having broad melt flow ratios.

Abstract: A supported catalyst for olefin polymerization comprises a selected ionic activator, a selected organometallic catalyst and a support material. The selected activator must contain an active hydrogen moeity. The organometallic catalyst is characterized by having a phosphinimine ligand and a substituted cyclopentadienyl ligand (which contains from 7 to 30 carbon atoms). The supported catalyst exhibits excellent activity in gas phase olefin polymerizations and may be used under substantially “non-fouling” polymerization conditions.

Abstract: The use of high activity “Single Site” polymerization catalysts often causes the fouling of polymerization reactors. The problem is particularly acute with gas phase polymerizations. While not wishing to be bound by theory it is believed that the fouling is initiated by the buildup of static charges in the reactor. The use of anti-static agents mitigates this problem, but typical antistatic agents contain polar species, which can deactivate the polymerization catalyst. We have now discovered that the use of a porous metal oxide support allows large levels of a selected antistatic agent to be used in a manner that reduces static/fouling problems in highly active polymerization catalysts.

Abstract: Single site catalysts which contain a transition metal, a cyclopentadienyl may be activated with alumoxanes in the gas, solution or group-containing ligand, and a phosphinimine ligand slurry phase polymerization of olefin. Alumoxanes contain residual aluminum alkyls which may poison the catalysts. The residual aluminum alkyls may be bound and/or removed from the alumoxanes by treatment with carbohydrates such as cellulose, starch or sugar.

Abstract: New group 4 organometallic complexes are characterized by having a phosphinimine ligand and two or more cyclopentadienyl ligands. Certain of these complexes exhibit unusual behavior when examined by nuclear magnetic resonance (NMR) techniques. Well defined crystals of the inventive complexes have been isolated and analyzed by x-ray crystallography. The complexes have also been found to be polymerization catalysts which are surprisingly more active than their simple metallocene analogs.

Abstract: A catalyst system comprises an organometallic complex of a group 4 metal having a ketimide ligand. The organometallic complex preferably also contains a cyclic ligand which forms a delocalized pi-bond with the metal (such as a cyclopentadienyltype ligand). Preferred organometallic complexes may be activated with a so-called “substantially non coordinating anion” to form a low cost cocatalyst system which is excellent for the preparation of olefin copolymers having both high molecular weight and very low density.

Abstract: Aluminoxanes are used as activators for the gas, solution or slurry phase polymerization of olefins in the presence of single site catalysts. Aluminoxanes contain residual aluminum alkyls which may poison the catalysts. The residual aluminum alkyls may be bound an/or removed from the aluminoxanes by treatment with carbohydrates such as cellulose, starch or sugar.

Abstract: Organometallic complexes of titanium or zirconium having only three ligands (namely a cyclopentadienyl ligand, a phosphinimine ligand and an activatable ligand) are catalyst components for olefin polymerization. Preferred polymerization systems are prepared by combining the organometallic complexes with an ionic activator and/or an alumoxane. Preferred catalyst components contain titanium (III) and are used in ethylene polymerization.

Abstract: A catalyst which is useful in slurry or gas phase olefin polymerizations and which is prepared by depositing a combination of an organometallic complex of a group 4 metal and a so-called ionic activator on a metal oxide support. The organometallic complex is characterized by being unbridged and by having a cyclopentadienyl ligand, a phosphinimine ligand and an activatable ligand. The “ionic activator” (for example, triphenylcarbenium tetrakis (pentafluorophenyl) boron) is co-deposited with the organometallic complex. The metal oxide support is pre-treated with, for example, an aluminum alkyl in an amount which is at least equivalent to the molar concentration of surface hydroxyls on the support.

Abstract: Aluminoxanes are used as activators for the gas, solution or slurry phase polymerization of olefins in the presence of single site catalysts. Aluminoxanes contain residual aluminum alkyls which may poison the catalysts. The residual aluminum alkyls may be bound an/or removed from the aluminoxanes by treatment with carbohydrates such as cellulose, starch or sugar.

Abstract: An organometallic complex of a group 4 metal having a cyclopentadienyl ligand and a heterosubstituted phosphinimine ligand is a catalyst component for olefin polymerization. The heterosubstituted phosphinimine ligand may be conveniently and inexpensively synthesized using readily available precursors which are comparatively non-pyrophoric. The resulting catalysts are highly active for ethylene copolymerization, particularly when activated with an alumoxane or ionic activator.

Abstract: A slurry polymerization process uses an unsupported catalyst component which is an organometallic complex having a phosphinimine ligand and a cyclopentadienyl-type ligand. The use of the unsupported catalyst component allows simple, inexpensive catalyst addition techniques to be used in a slurry polymerization process. The catalyst component is highly active for ethylene (co)polymerization in the process of this invention.

Abstract: The present invention provides a novel process for preparing a catalyst, preferably free of electron donor, useful in gas phase polymerization of olefins having a broad polydispersity.