Catalyst systems and methods for making and using the same. A method of polymerizing olefins to produce a polyolefin polymer with a multimodal composition distribution, includes contacting ethylene and a comonomer with a catalyst system. The catalyst system includes a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system. The first catalyst compound includes a compound with the general formula (C.sub.5H.sub.aR.sup.1.sub.b)(C.sub.5H.sub.cR.sup.2.sub.d)HfX.sub.2. The second catalyst compound comprises the following formula:

##STR00001##

wherein each R.sup.3 or R.sup.4 is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R.sup.3 or R.sup.4 may be the same or different, and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R.sup.3 group.

Ethylene-based polymers having a density of 0.952 to 0.968 g/cm.sup.3, a ratio of HLMI/MI from 185 to 550, an IB parameter from 1.46 to 1.80, a tan δ at 0.1 sec.sup.−1 from 1.05 to 1.75 degrees, and a slope of a plot of viscosity versus shear rate at 100 sec.sup.−1 from 0.18 to 0.28 are described, with low melt flow versions having a HLMI from 10 to 30 g/10 min and a Mw from 250,000 to 450,000 g/mol, and high melt flow versions having a HLMI from 30 to 55 g/10 min and a Mw from 200,000 to 300,000 g/mol. These polymers have the processability of chromium-based resins, but with improved stress crack resistance and topload strength for bottles and other blow molded products.

Catalyst systems and methods for making and using the same. A method of methylating a catalyst composition while substantially normalizing the entiomeric distribution is provided. The method includes slurrying the organometallic compound in dimethoxyethane (DME), and adding a solution of RMgBr in DME, wherein R is a methyl group or a benzyl group, and wherein the RMgBr is greater than about 2.3 equivalents relative to the organometallic compound. After the addition of the RMgBr, the slurry is mixed for at least about four hours. An alkylated organometallic is isolated, wherein the methylated species has a meso/rac ratio that is between about 0.9 and about 1.2.

This invention relates to catalyst systems comprising a catalyst compound having a bridged group 4 metal metallocene (where the bridge preferably contains an (Me.sub.2Si).sub.2 group, an activator, and a support material. In some embodiments, the present disclosure provides for polyolefins and a process for producing a polyolefin composition comprising contacting at least one olefin with a catalyst system.

The present invention provides polyolefin resin composition exhibiting excellent long term durability as well as improved properties, and an article prepared using the same.

A transition metal compound having a novel structure is disclosed herein. The transition metal compound can have improved structural stability by forming a stable coordination site of a transition metal through controlling a bond angle formed by the amido group of a phenylene bridge, a cyclopentadienyl ring, and a transition metal. The transition metal compound has excellent copolymerization properties and may produce an olefin polymer having a high molecular weight in a ultra low density region.

Catalyst system for producing ethylene copolymers in a high temperature solution process, the catalyst system comprising: (i) a metallocene complex of formula (I) ##STR00001## wherein M is Hf or a mixture with Zr, provided that more than 50% by moles of the complex of Formula I has M=Hf; X is a sigma ligand; R are the same or different from each other and can be saturated linear or branched C.sub.1-C.sub.10 alkyl, C.sub.6-C.sub.10 aryl, C.sub.4-C.sub.10 heteroaryl, C.sub.6-C.sub.20 alkylaryl or C.sub.6-C.sub.20 arylalkyl groups, which can optionally contain up to 2 heteroatoms or silicon atoms; R.sup.1 is a C.sub.6-C.sub.10 aryl or C.sub.6-C.sub.20 alkylaryl group optionally containing up to 2 heteroatoms or silicon atoms or a C.sub.4-C.sub.10 heteroaryl group; R.sup.2 is a C.sub.4-C.sub.20 cycloalkyl group, optionally carrying alkyl substituents in beta-positions, of formula (II) ##STR00002## in which R′ can be the same or can be different from each other and can be hydrogen or is defined as R and n is 1 to 17; and (ii) a boron containing cocatalyst.

Provided is a hybrid catalyst composition including a first transition metal compound represented by Formula 1 and a second transition metal compound represented by Formula 2, the compounds being different from each other in the Formulae. The hybrid catalyst composition including the first and second transition metal compounds may exhibit high catalytic activity and may prepare a polyolefin having processability and mechanical properties.

The invention relates to a metallocene complex according to formula A, wherein R1-R10 are independently selected from H, C1-C10 alkyl, C7-C20 Aralkyl groups, and C1-C10 alkoxy groups; wherein R11 is selected from methyl, ethyl, propyl, isopropyl, butyl, phenyl; wherein R1 and R2, R3 and R4, R4 and R5, R5 and R6, R7 and R8, R8 and R9, and/or R9 and R10 can be connected to form a ringstructure; wherein R0 is selected from a C1-C10 alkyl group or an aryl group wherein M is selected from Ti, Zr and Hf, X is an anionic ligand to M, z is the number of X groups and equals the valence of M minus 2. The invention further relates to a catalyst for preparing polyolefins, a process for polymerizing olefins and to polymers prepared by said catalyst system. ##STR00001##

Catalyst systems and methods for making and using the same. A method of methylating a catalyst composition while substantially normalizing the entiomeric distribution is provided. The method includes slurrying the organometallic compound in dimethoxyethane (DME), and adding a solution of RMgBr in DME, wherein R is a methyl group or a benzyl group, and wherein the RMgBr is greater than about 2.3 equivalents relative to the organometallic compound. After the addition of the RMgBr, the slurry is mixed for at least about four hours. An alkylated organometallic is isolated, wherein the methylated species has a meso/rac ratio that is between about 0.9 and about 1.2.