Abstract: Propylene and alpha olefin random copolymers are disclosed that have excellent flow characteristics. For instance, the copolymers can be formulated so as to have a melt flow rate of greater than about 45 g/10 min. While still retaining the above flow characteristics, the copolymer can also be formulated to have greater stiffness, low xylene soluble content, and excellent transparency characteristics especially when combined with one or more clarifying agents.

Abstract: Organosilicon compounds having a structure represented by the general formula and a method for using same are provided as electron donors in the Ziegler-Natta type catalyst system for the homo-polymerization or co-polymerization of alpha olefins. The organosilicon compounds may be used in the preparation of the solid catalyst component, thus serving as “internal electron donors”, or employed during or prior to polymerization as “external electron donors,” and therefore they can be used to prepare phthalate-free polyolefins.

Abstract: The present invention relates to a novel process for the synthesis of 9,9-bis(hydroxymethyl)fluorene. The syntheses from fluorene to 9,9-bis(hydroxy-methyl)fluorene via a hydroxymethylation and further to 9,9-bis(methoxymethyl)-fluorene via a etherification are known. 9,9-bis(methoxymethyl)fluorene is a compound that is used as an electron donor for Ziegler-Natta catalysts. The present invention is related to an improvement in the synthesis of 9,9-bis(hydroxymethyl)fluorene leading to a decrease in the amount of solvent used and an easier work up while achieving high yield and purity.

Abstract: A composite may include polylactic acid, polyethylene, and optionally a compatibilizer. The composite may be formed by combining the polylactic acid with the polyethylene. The composite may be formed into an extruded article.

Abstract: A method is provided to control the short chain branching (SCB) distribution of an ethylene-butene (EB) polyethylene resin that is prepared in a gas phase polymerization process using a specific type of magnesium-titanium Ziegler Natta catalyst. The method allows the level of short chain branching to be increased in the low molecular weight fraction of the resin by increasing the polymerization residence time. The polymers that are produced in accordance with this invention may be useful for the preparation of cast films and blown films, especially for stretch film applications.

Abstract: The present invention relates to a procatalyst comprising the compound represented by Formula (A), preferably the Fischer projection of formula (A) as an internal electron donor. The invention also relates to a process for preparing said procatalyst. Furthermore, the invention is directed to a catalyst system for polymerization of olefins comprising the said procatalyst, a co-catalyst and optionally an external electron donor; a process of making polyolefins by contacting at least one olefin with said catalyst system and to polyolefins obtainable by said process. The invention also relates to the use of said procatalyst in the polymerization of olefins. Moreover, the present invention relates to polymers obtained by polymerization using said procatalyst and to the shaped articles of said polymers.

Abstract: This disclosure provides for new catalyst systems and new methods for preparing and using the catalyst systems for generating a trimerization product. In an aspect, the new catalyst systems comprise a chromium carboxylate that is prepared by anhydrous metathesis. In another aspect, the catalyst system comprise a chromium carboxylate that is prepared by anhydrous metathesis and a metal pyrrolide compound. The catalyst systems imparts improved performance and/or reduced catalyst system cost to an olefin trimerization process.

Abstract: The present invention describes a process for controlling particle size of a catalyst composition. The process comprising the steps of contacting an internal donor with an organomagnesium precursor solution to form an intermediate solution and treating the intermediate solution with a transition metal compound to form a catalyst composition, wherein particle size of the catalyst composition is controlled by controlling a contact time of the internal donor with the precursor solution during formation of the intermediate solution.

Abstract: A solid adduct comprising magnesium chloride and ethanol in which the moles of ethanol per mole of magnesium chloride range from 2 to 5 and in which the ratio between the average pore radius measured in Angstrom of said adduct, determined by mercury porosity, and the moles of ethanol, is higher than 500.

Abstract: Procatalyst comprising an inorganic support, a chlorine compound carried on said support, a magnesium compound carried on said support, a titanium compound carried on said support, and a compound comprising two oxygen containing rings, wherein said two rings are linked via a bridge selected from the group consisting of carbon bridge, silicon bridge, ethane-1.2-diyl bridge, ethene-1,2-diyl bridge, alkylaminomethyl bridge and imine bridge.

Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a mono or dihalogenated hydrocarbon compound. Said catalyst systems have improved polymerization activity.

Abstract: Prepolymerized catalyst component for the polymerization of olefins CH2?CHR in which R is hydrogen or a hydrocarbyl radical with 1-12 carbon atoms, having average particle size equal to or lower than 30 ?m comprising a solid catalyst component comprising magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds one of which being selected from 1,3-diethers and the other one being selected from esters of aromatic mono or dicarboxylic acids, said solid catalyst component being prepolymerized with an olefin, having from 2 to 10 carbon atoms, to such an extent that the amount of the olefin prepolymer is equal to or lower than 50 g per g of solid catalyst component.

Abstract: Catalyst and solid component of catalyst for the (co)polymerization of ethylene, comprising titanium, magnesium, chlorine, a protic organo-oxygenated compound Dp and a neutral aprotic electron-donor compound D, in the following molar ranges: Mg/Ti=1.0-50; D/Ti=1.0-15; Cl/Ti=6.0-100; Dp/D=0.05-3; and a process for obtaining said component.

Abstract: Solid catalyst with a high thermal stability for the (co)polymerization of ?-olefins, comprising titanium, magnesium, at least one metal selected from hafnium and zirconium, aluminum and chlorine, wherein at least 60% of the titanium is in oxidation state +3, and, when examined by means of XPS spectroscopy, has an absorption band characteristic of a binding energy ranging from 455 to 458 eV. Said catalyst, used in combination with a suitable co-catalyst in (co)polymerization processes of ?-olefins at a high temperature, shows an improved productivity, a high incorporation of co-monomers in the copolymerization of ethylene and an increased thermal stability with respect to the systems so far in use.

Abstract: Multimodal polyethylene resins having improved stress crack resistance and melt strength rendering them useful for the manufacture of thick-walled pipe are produced in a process wherein the second stage of the process is a copolymerization conducted at a high temperature with a low comonomer to ethylene ratio and a low hydrogen to ethylene ratio.

Abstract: The present invention relates to a process for the production of propylene polymers in the presence of a blend of a first Ziegler-Natta catalyst, which comprises a titanium compound having at least one titanium-halogen bond and a diether compound as internal electron donor, and a second Ziegler-Natta catalyst, which comprises a titanium compound having at least one titanium-halogen bond and a succinate compound as internal electron donor.

Abstract: A process for producing a substituted metallocene compound comprises reacting a first compound with a transfer-agent, wherein the first compound comprises a complex of a transition metal atom selected from Group 3, 4, 5 or 6 of the Periodic Table of Elements, or a lanthanide metal atom, or actinide metal atom and at least one monocyclic or polycyclic ligand that is pi-bonded to M and is substituted with at least one halogen or sulfonate substituent and the transfer-agent comprises a hydrocarbyl, substituted hydrocarbyl, halocarbyl, substituted halocarbyl, silylcarbyl, or germylcarbyl radical capable of replacing said at least one halogen or sulfonate substituent of said first compound under reaction conditions.

Abstract: Polyolefin production using an improved catalyst system and, in particular, a method for production of a polyolefin is disclosed. One or more monomers are contacted with a catalyst system. The catalyst system includes titanium tetrachloride as a catalyst precursor and magnesium ethylate as a support for the catalyst precursor. The catalyst system also includes a hydrocarbyl aluminum cocatalyst represented by the formula R3Al, where R is an alkyl radical having 1 to 14 carbon atoms, and where the molar ratio of the hydrocarbyl aluminum cocatalyst to the titanium tetrachloride catalyst precursor ranges from 50:1 to 400:1. The catalyst system also includes a halogenated hydrocarbon as a promoter, where the molar ratio of the halogenated hydrocarbon promoter to the titanium tetrachloride catalyst precursor ranges from 0.001:1 to 300:1.

Abstract: The present invention relates to a process and to an apparatus for continuous living polymerization of cationically polymerizable monomers, in which at least three feedstocks are mixed in one or more mixers with microstructures and then polymerized in at least one reaction zone.

Abstract: An interpolymer of ethylene and at least one alpha-olefin is claimed, wherein the ethylene interpolymer is characterized as having an average Mv and a valley temperature between the interpolymer and high crystalline fraction, Thc, such that the average Mv for a fraction above Thc from ATREF divided by average Mv of the whole polymer from ATREF (Mhc/Mp) is less then about 1.95 and wherein the interpolymer has a CDBI of less than 60%. The interpolymer of ethylene and at least one alpha-olefin can also be characterized as having a high density (HD) fraction and an overall density such that % HD fraction<?2733.3+2988.7x+144111.5 (x?0.92325)2 where x is the density in grams/cubic centimeter. Fabricated articles comprising the novel interpolymers are also disclosed.

Abstract: The invention relates to a process for the production of bimodal polyethylene in a two-step polymerisation process in the presence of a catalyst system comprising: (I) the solid reaction product obtained by reacting of: a) a hydrocarbon solution containing 1) an organic oxygen containing magnesium compound or a halogen containing magnesium compound and 2) an organic oxygen containing titanium compound and b) an aluminium halogenide having the formula AIRnX3-n in which R is a hydrocarbon radical containing 1-10 carbon atoms, X is halogen and 0<n<3 (II) an aluminium compound having the formula AIR3 in which R is a hydrocarbon radical containing 1-10 carbon atom and (III) an electron donor selected from the group of 1,2-dialkoxyalkanes and 1,2-dialkoxyalkenes wherein in the first step a low molecular weight polyethylene is produced which has a MFI190/1.

Abstract: A pre-polymerized catalyst component for the polymerization of olefins endowed with high activity and morphological stability comprises a non-stereospecific solid catalyst component containing Ti, Mg and a halogen, and an amount of an ethylene/alpha-olefin block (co)polymer ranging from 0.1 up to 5 g per g of said solid catalyst component, said prepolymerized catalyst component being characterized by a mercury porosity, due to pores having radius up to 1 ?m, ranging from 0.15 to 0.5 cm3/g and by the fact that at least 55% of said porosity is due to pores having pore radius up to 0.2 ?m.

Abstract: A solid catalyst component for olefin polymerization, comprising titanium atoms, magnesium atoms, halogen atoms and hydrocarbyloxy groups, wherein the following filtrate contains titanium atoms in a concentration of 0.08 mg-Ti/ml-filtrate or lower, measured according to a method comprising the steps of (1) preparing a suspension of the solid catalyst component for olefin polymerization in heptane having a concentration of 0.1 g-solid catalyst component/ml-suspension, (2) heating the suspension at 70° C. for 30 minutes under stirring, (3) filtering the suspension, thereby obtaining a filtrate, and (4) measuring a concentration of titanium atoms contained in the filtrate; and a production process of the solid catalyst component.

Abstract: An olefin polymer that is obtained using an olefin polymerization catalyst that includes a solid catalyst component for olefin polymerization that includes titanium, magnesium, a halogen, and an ester compound (A) represented by the following formula (1): R1R2C?C(COOR3)(COOR4), an organoaluminum compound, and an optional external electron donor compound, exhibits primary properties (e.g., molecular weight distribution and stereoregularity) similar to those of an olefin polymer obtained using a solid catalyst component that includes a phthalic ester as an electron donor.

Abstract: New ethylene polymers having broad molecular weight distribution and long-chain branching, above all at high molecular weight fractions; the polymers have strain hardening equal or higher than 1.4 (at constant elongational rate of 0.5 s?1, at 150° C.), branching index g? equal or lower than 0.9 (at Mw of 2·106 g/mol). The polymers are prepared by using a mixed catalyst system comprising a polymerization catalyst based on a late transition metal component having a tridentate ligand, and a Ziegler polymerization catalyst annealed at a temperature higher than 100° C., for a time of at least 10 minutes.

Abstract: The present invention relates to a magnesium compound-supported nonmetallocene catalyst, which is produced by directly contacting a catalytically active metallic compound with a nonmetallocene ligand-containing magnesium compound, or by directly contacting a nonmetallocene ligand with a catalytically active metal-containing magnesium compound, through an in-situ supporting process. The process is simple and flexible. In the process, there are many variables in response for adjusting the polymerization activity of the catalyst, and the margin for adjusting the catalyst load or the catalyst polymerization activity is broad. The magnesium compound-supported nonmetallocene catalyst according to this invention can be used for olefin homopolymerization/copolymerization, in combination with a comparatively less amount of the co-catalyst, to achieve a comparatively high polymerization activity. Further, the polymer product obtained therewith boasts high bulk density and adjustable molecular weight distribution.

Abstract: A catalyst composition that includes a support material having an improved particle-size distribution is provided. Processes for producing polyolefin composition also are provided. Polymers and films also are provided. An example of a catalyst composition is a supported multi-transition-metal catalyst composition that includes: (a) at least two catalyst components selected from the group consisting of: a nonmetallocene catalyst component and a metallocene catalyst component; (b) a support material that has a D50 of less than about 30 microns and a particle size distribution having a D90/D10 ratio of less than about 6; and (c) an activator.

Abstract: The present invention provides a process for producing an ?-olefin polymer comprising polymerizing or copolymerizing (a) C3 or higher ?-olefin(s) in the presence of an olefin polymerization catalyst comprising solid titanium catalyst component (I) containing titanium, magnesium, halogen, and a compound with a specific structure having two or more ether linkages and organometallic catalyst component (II) with high catalytic activity. In this process, particularly even in (co)polymerizing (a) higher olefin(s), demineralization is unnecessary. A 4-methyl-1-pentene-based polymer obtained by polymerization using the catalyst of the present invention is excellent in tacticity, transparency, heat resistance, and releasability, and the polymer is particularly suitable for a release film.

Abstract: Disclosed are procatalyst compositions having an internal electron donor which includes a substituted amide ester and optionally an electron donor component. Ziegler-Natta catalyst compositions containing the present procatalyst compositions exhibit improved catalyst activity and/or improved catalyst selectivity and produce propylene-based olefins with broad molecular weight distribution.

Abstract: Disclosed are catalyst compositions for isoprene polymerization formed from components comprising (A) at least one titanium halide; (B) at least one organic aluminum compound comprising at least one alkyl aluminum of formula AlR3, wherein each of the three Rs is independently chosen from linear and branched C1-6 alkyl groups; and (C) at least one electron donor comprising at least one polyether compound of formula (I) and/or at least one tetrahydro-furfuryl ether compound of formula (II). Also disclosed are processes for preparation of the catalyst compositions and processes using the catalyst compositions for isoprene polymerization.

Abstract: A catalyst system for the polymerization of olefins comprising (A) a catalyst component obtained by reacting a Mg(OR1)(OR2) compound, in which R1 and R2 are identical or different and are each an alkyl radical having 1 to 10 carbon atoms, with a tetravalent transition metal compound having at least a Metal-halogen bond, used in amounts such that the molar ratio Met-al/Mg is from 0.05 to 10; (B) an aluminum alkyl compound and (C) a linear or branched halogenated alkyl compound.

Abstract: The invention relates to a bimodal or multimodal polyethylene which comprises ethylene homopolymers and/or copolymers of ethylene with ?-olefins, has a polydispersity index Mw/Mn of the low molecular weight component of less than 10 and can be prepared using a polymerization catalyst based on a Ziegler component and a late transition metal component having a tridentate ligand which bears at least two ortho,ortho-disubstituted aryl radicals and also a catalyst system and a process for preparing the polyethylene and also fibers, moldings, films and polymer blends comprising this material.

Abstract: A solid catalyst component comprising Ti, Mg, halogen and a couple of monofunctional electron donor compounds MD1 and MD2 selected from esters and ethers, said donors being present in amounts such that the molar ratio MD1/MD2 ranges from 20 to 800. The so obtained catalyst component when converted into a catalyst is able to produce ethylene polymers with good morphological properties even under drastic polymerization conditions.

Abstract: A method for transitioning from a Ziegler-Natta to a Phillips catalyst system for the olefin polymerization reaction in one reactor, preferably a gas phase reactor, is described. The method comprises the steps of a) discontinuing a first olefin polymerization reaction performed in the presence of the Ziegler-Natta catalyst system; b) performing a second olefin polymerization reaction in the presence of a further catalyst system comprising catalyst components (A) and (B) producing, respectively, a first and a second polyolefin fraction, wherein the Mw of the first polyolefin fraction is less than the Mw of the second polyolefin fraction and the initial activity of catalyst component (A) exceeds the initial activity of catalyst component (B); and c) performing a third olefin polymerization reaction the presence of the Phillips catalyst system.

Abstract: A catalyst for olefin polymerization and method of preparing the same are disclosed.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing an internal electron donor, a support made by contacting substantially equal molar amounts of a magnesium compound and an epoxy compound in the presence of an aprotic solvent and subsequent treatment with a halogenating agent to provide a magnesium based catalyst support. The catalyst system can further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of polymerizing or copolymerizing an alpha-olefin. The methods involve contacting an olefin with a catalyst system containing the solid titanium catalyst component.

Abstract: The present invention relates to a process for the production of fibres and filaments with polypropylene having a broad polydispersity index. The present invention also relates to high elongation nonwoven prepared from such fibres and filaments. It further relates to films and laminates prepared from high elongation nonwoven.

Abstract: A solid, hydrocarbon-insoluble, catalyst component useful in polymerizing olefins containing magnesium, titanium, and halogen further contains an internal electron donor comprising a compound containing electron donating substituents with a structure: wherein D1 and D2 are selected individually from and R, R1, R2, R3, R4, R5, R6, and R7 individually are hydrocarbon or substituted hydrocarbon groups containing 1 to 20 carbon atoms and R1, R2, R3, R4, R6, and R7 may be hydrogen; R4 may be —NR2; and wherein groups R1 and R2, R2 and R3, R3 and R4, R3 and R5, and groups R6 and R7 may be joined to form a cyclic structure.

Abstract: Adducts are provided comprising MgCl2, ethanol and a Lewis base (LB), said compounds being present in molar ratios defined by the following formula MgCl2.(EtOH)n(LB)p in which n is from 2 to 6 and p has values satisfying the following equation p/(n+p)?0.1. The said adducts can be used as precursor in the preparation of high activity ZN catalysts.

Abstract: A solid catalyst component for olefin polymerization comprising a titanium atom, a magnesium atom, a halogen atom, and a cycloheptapolyenedicarboxylic diester; a production method of the solid catalyst component, by contacting with one another a titanium compound, a magnesium compound, and the cycloheptapolyenedicarboxylic diester; a production method of a solid catalyst, by contacting the solid catalyst component with an organoaluminum compound; and a production method of an olefin polymer by polymerizing an olefin in the presence of the solid catalyst.

Abstract: A process for the preparation of 1-butene homopolymers or 1-butene/alpha olefin copolymers wherein the alpha olefins are selected from ethylene, propylene or alpha olefins of formula CH2?CHZ wherein Z is a C3-C20 alkyl radical, comprising contacting 1-butene or 1-butene and one or more alpha olefins under polymerization conditions in the presence of a catalyst system comprising: (a) a solid component comprising a Ti compound and an internal electron-donor compound supported on MgCl2 (b) an alkylaluminum cocatalyst; and (c) a compound of formula (I) as external donor Wherein: R1, R2, R3 and R4, equal to or different from each other, are hydrogen atoms or C1-C20 hydrocarbon radicals optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; or two R1, R2, R3 and R4 can be joined to form a C5-C20, saturated or unsaturated ring.

Abstract: The invention refers to a process for preparing a Group 2 metal/transition metal olefin polymerization catalyst component in particulate form having improved polymerization properties due to the use of H2 during catalyst component preparation and the use of such catalyst components in a process for polymerizing olefins.

Abstract: The present invention relates to an ultrahigh-molecular-weight ethylene copolymer powder having an intrinsic viscosity (?) of 10 dl/g to 34 dl/g, obtainable by copolymerizing ethylene and at least one olefin selected from the group consisting of ?-olefins having 3 to 20 carbon atoms, cyclic olefins having 3 to 20 carbon atoms, compounds represented by the formula CH2?CHR1 wherein R1 is an aryl group having 6 to 20 carbon atoms, and linear, branched or cyclic dienes having 4 to 20 carbon atoms, wherein (1) a molded article of the copolymer powder has a haze of from 30% to 80% and (2) the copolymer powder has a bulk density of from 0.35 g/cm3 to 0.6 g/cm3.

Abstract: The present techniques relate to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene compound comprising bridging ?5-cyclopentadienyl-type ligands, typically in combination with a cocatalyst, and a activator. The compositions and methods presented herein include ethylene polymers with low melt elasticity.

Abstract: A bimodal polyethylene having a high density ranging from about 0.955 to about 0.959 g/cc, an improved environmental stress cracking resistance (ESCR) of from about 400 to about 2500 hours, and an improved 0.4% flexural modulus of from about 180,000 to about 260,000 psi (1,200 MPa to about 1,800 MPa) may be formed using a Ziegler-Natta polymerization catalyst using two reactors in series. The bimodal polyethylene may have a high load melt index (HLMI) of from about 2 and about 30 dg/min and may be optionally made with a small amount of alpha-olefinic comonomer in the second reactor. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Low-viscosity drag reducers, systems for delivering low-viscosity drag reducers, and methods of making low-viscosity drag reducers are disclosed. The low-viscosity drag reducers have a viscosity less than 350 cP at a shear rate of 250 sec?1 and a temperature of 60° P. This low-viscosity allows the drag reducers to be delivered through a long and relatively small diameter conduit of a subsea umbilical line without an unacceptable level of pressure drop or plugging of the conduit. The low-viscosity drag reducers can be delivered to a subsea flowline carrying fluids produced from a subterranean formation to 10 thereby provide significant drag reduction in the flow line.

Abstract: Disclosed is a bimodal Ziegler-Natta catalyzed polyethylene, having a density of from 0.930 g/cc to 0.960 g/cc, and a molecular weight distribution of from 10 to 25, wherein an article formed therefrom has a PENT of at least 1500. Also disclosed is a method of preparing a tubular article including obtaining a bimodal polyethylene having a density of from 0.930 g/cc to 0.960 g/cc and a molecular weight distribution of from 10 to 25, and processing the polyethylene under conditions where a specific energy input (SEI) is less than 300 kW·h/ton, and wherein the article has a PENT of at least 1500. Further disclosed is a method for controlling the degradation of polyethylene including polymerizing ethylene monomer, recovering polyethylene, extruding the polyethylene, and controlling the degradation of polyethylene by measuring the SEI to the extruder and adjusting throughput and/or gear suction pressure keep SEI less than 300 kW·h/ton, and forming an article.

Abstract: A solid catalyst component for olefin polymerization containing a titanium atom, a magnesium atom, a halogen atom, and a defined internal electron donor such as dodecanedioyl dichloride; a production process of such a solid catalyst component, using a titanium compound, a magnesium compound, and the above internal electron donor, or using a solid component containing a titanium atom and a magnesium atom, and the above internal electron donor; a production process of a solid catalyst, using (i) the above solid catalyst component, (ii) an organoaluminum compound, and (iii) an external electron donor; and a production process of an olefin polymer using the above solid catalyst.

Abstract: A catalyst component comprising Ti, Mg, Al, Cl, and optionally ORI groups in which RI is a C1-C20 hydrocarbon group, optionally containing heteroatoms, up to an amount such as to give a molar ORI/Ti ratio lower than 0.5, characterized by the fact that substantially all the titanium atoms are in valence state of 4, that the porosity (PF), measured by the mercury method and due to pores with radius equal to or lower than 1 ?m, is at least 0.3 cm3/g, and by the fact that the Cl/Ti molar ratio is lower than 29. The said catalysts are characterized by high morphological stability under the low molecular weight ethylene polymerization conditions while at the same time maintaining characteristics of high activity.

Abstract: The present invention relates generally to catalysts, to methods of making catalysts, to methods of using catalysts, to methods of polymerizing, and to polymers made with such catalysts. More particularly, the present invention relates to polyolefin catalysts and to Ziegler-Natta catalysts, to methods of making such catalysts, to methods of using such catalysts, to polyolefin polymerization, and to polyolefins.