Abstract: An ethylene polymerization process is disclosed. Ethylene is polymerized in two slurry reaction zones with a C6-C10 alpha-olefin in the presence of a single-site catalyst capable of making a high molecular weight polyolefin. The process yields medium density and linear low density polyethylene having a bimodal molecular weight distribution and a melt index from about 0.10 to about 0.80. Films from the polyethylene have superior impact properties.

Abstract: Disclosed is a novel bidentate pyridine transition metal catalyst having the general formula each R is independently selected from hydrogen or C1 to C6 alkyl, or C6 to C14 aryl, each R′ is independently selected from R, C1 to C6 alkoxy, C6 to C14 aryl, C7 to C20 alkaryl, C7 to C20 aralkyl, halogen, or CF3, M is a Group 3 to 10 metal, each X is independently selected from halogen, C1 to C6 alkyl, C6 to C14 aryl, C7 to C20 alkaryl, C7 to C20aralkyl, C1 to C6 alkoxy, or L is X, cyclopentadienyl, C1 to C6 alkyl substituted cyclopentadienyl, indenyl, fluorenyl, or “n” is 1 to 4; “a” is 1 to 3; “b” is 0 to 2; a+b≦3; “c” is 1 to 6; and a+b+c equals the oxidation state of M.

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.

Abstract: Disclosed is a novel bidentate pyridine transition metal catalyst having the general formula where each R is independently hydrogen, C1-6 alkyl, or C6-14 aryl; where each R′ is independently R, C1-6 alkoxy, C7-20 alkaryl, C7-20 aralkyl, halogen, or CF3; where M is a Group 3 to 10 metal; where each X is independently halogen, C1-6 alkyl, C6-14 aryl, C7-20 alkaryl, C7-20 aralkyl, C1-6 alkoxy, or  L is X, cyclopentadienyl, C1-16 alkyl-substituted cyclopentadienyl, fluorenyl, indenyl, or  where n is an integer from 1 to 4; a is an integer from 1 to 3; b is an integer from 0 to 2; the sum of a+b≦3; c is an integer from 1 to 6; and the sum a+b+c equals the oxidation state of M.

Abstract: Disclosed is a novel bidentate pyridine transition metal catalyst having the general formula 1

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.

Abstract: A process for preparing boratabenzene derivatives is provided. The process includes the hydrogenation of a compound containing a boranaphthalene functional group to form a boratabenzene-containing compound. Depending on the compound containing a boranaphthalene functional group, the resulting boratabenzene compound may be converted into a catalyst suitable for olefin polymerization. A process for forming a boratabenzene derivative from a halo-dioxaborolane is also provided. In this process, a halo-dioxaborolane is reacted with a piperylide salt for form a pentadienyl dioxaborolane. The pentadienyl-dioxaborolane is reacted with a strong base to form an intermediate boratacyclohexanediene salt. The intermediate boratacyclohexanediene salt is then reacted with a trialkylaluminum compound to form an alkylboratabenzene salt.

Abstract: A process for preparing boratabenzene derivatives is provided. The process includes the hydrogenation of a compound containing a boranaphthalene functional group to form a boratabenzene-containing compound. Depending on the compound containing a boranaphthalene functional group, the resulting boratabenzene compound may be converted into a catalyst suitable for olefin polymerization. A process for forming a boratabenzene derivative from a halo-dioxaborolane is also provided. In this process, a halo-dioxaborolane is reacted with a piperylide salt for form a pentadienyl dioxaborolane. The pentadienyl-dioxaborolane is reacted with a strong base to form an intermediate boratacyclohexanediene salt. The intermediate boratacyclohexanediene salt is then reacted with a trialkylaluminum compound to form an alkylboratabenzene salt.

Abstract: A blend comprising a high molecular weight, medium density polyethylene (HMW, MDPE) and a linear low density polyethylene (LLDPE) is disclosed. The blend comprises from about 20 wt % to about 80 wt % of HMW MDPE. The HMW MDPE has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. The blend also comprises about 20 wt % to about 80 wt % of LLDPE. The LLDPE has a density within the range of about 0.90 to about 0.925 g/cc and an MI2 within the range of about 0.50 to about 50 dg/min. The blend provides films with significantly improved toughness and tear strength compared to MDPE or HDPE, and high modulus compared to LLDPE.

Abstract: A constrained geometry single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an organometallic compound that includes a Group 3 to 10 transition or lanthanide metal, M, and a multidentate ligand characterized by an indolyl group that is covalently linked to an amido group, wherein the indolyl group is &pgr;-bonded to M and the amido group is &sgr;-bonded to M. The indolyl-amido ligand is formed from readily available organic compounds and allows easy synthesis of a constrained geometry catalyst system.

Abstract: A supported olefin polymerization catalyst system and a method of making it are disclosed. The catalyst system comprises: (a) a support chemically treated with an organoaluminum, organosilicon, organomagnesium, or organoboron compound; (b) a single-site catalyst that contains a polymerization-stable, heteroatomic ligand; and (c) an activator. Chemical treatment is a key to making supported heterometallocenes that have high activity and long shelf-lives, and can effectively incorporate comonomers.

Abstract: A two-step olefin polymerization process is disclosed. A single-site catalyst precursor reacts with a boron-containing activator and a first olefin substantially in the absence of an alumoxane to produce a stable, prepolymer complex, which is then used to polymerize a second olefin in the presence of a scavenging amount of an alumoxane. The process gives high molecular weight polyolefins with low residual aluminum contents. Boron-containing activators can be used, even at reaction temperatures greater than 100° C., while maintaining high catalyst activity.

Abstract: A multiple stage or multiple zone process for making olefin polymers is disclosed. A single-site catalyst, preferably one that contains a heteroatomic ligand, is used in the first stage or zone, and a Ziegler-Natta catalyst is used at a higher temperature in later stages or zones. A parallel multiple zone process is also described. The processes, which can be performed adiabatically, give polymers with improved thermal processing ability.

Abstract: Catalysts for the polymerization of olefins contain units of the formula: wherein ##STR1## each R is independently selected from a C.sub.1 to C.sub.10 aliphatic or cycloaliphatic group or a C.sub.6 to C.sub.18 aryl, aralkyl, or alkaryl;each R.sup.2 is independently selected from hydride, R, and Q radicals wherein at least one R.sup.2 is Q;Q has the general formulaLM.sup.p L'.sub.r X.sub.p-r-1whereinL is a monoanionic aromatic ancillary ligand pi-bonded to M and covalently bonded to Si;L' is a monoanionic aromatic ancillary ligand pi-bonded to M and optionally bonded to L through a covalent bridging group;M is a metal selected from Groups 3-10 of the Periodic Table or lanthanides;X is independently selected from a hydride radical, halide radical, hydrocarbyl radical, halocarbyl radical, silahydrocarbyl, alkoxy radical, aryloxy radical, alkylsulfonate radical, arylsulfonate radical or (R).sub.

Abstract: A catalysis system containing an olefin polymerization catalyst having at least one Group 3 to Group 10 transition metal or one of the Lanthanide series of the Periodic Table and an organic support is homogeneous and has particular applicability in the production of polyolefins having narrow molecular weight distribution. The support of the catalysis system is the reaction product of a silicone and a polyamine. The catalysis system has high thermal stability.

Abstract: Disclosed is a novel bidentate pyridine transition metal catalyst having the general formula ##STR1## where Y is O, S, NR, ##STR2## each R is independently selected from hydrogen or C.sub.1 to C.sub.6 alkyl, each R' is independently selected from C.sub.1 to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkoxy, C.sub.6 to C.sub.16 aryl, halogen, or CF.sub.3, M is titanium, zirconium, or hafnium, each X is independently selected from halogen, C.sub.1 to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkoxy, or ##STR3## L is X, cyclopentadienyl, C.sub.1 to C.sub.6 alkyl substituted cyclopentadienyl, indenyl, fluorenyl, or ##STR4## and "n" is 1 to 4. Also disclosed is a method of making a poly-.alpha.-olefin comprising polymerizing an .alpha.-olefin monomer using that catalyst or a catalyst that has the general formula ##STR5## where Y, M, L, X, and R' were previously defined.

Abstract: A multiple site solid catalyst component capable of producing polyolefins having a broad or multimodal molecular weight distribution, such as a bimodal molecular weight distribution, is prepared by contacting a particulate solid support with a zirconium compound or complex to bind the zirconium compound or complex to the support, optionally followed by contacting the supported zirconium compound or complex with a Lewis acid to produce an intermediate product, optionally isolating and washing the supported zirconium compound or complex or resulting intermediate product to remove soluble by-products therefrom, and reacting the washed or unwashed supported zirconium compound or complex or intermediate product with a titanium or vanadium compound to produce a solid catalyst component.

Abstract: A method of using a catalyst with a suitable cocatalyst in the polymerization or copolymerization of 1-olefins are disclosed. The catalyst is prepared by: a) contacting a Group IIA organometallic compound, like 2-methylpentanoxymagnesium chloride, or a Group III organometallic compound, like triethylaluminum, or a combination thereof, with a porous or nonporous biodegradable substrate having active surface hydroxyl groups, like cellulose, to provide a modified biodegradable substrate; then b) contacting the modified biodegradable substrate with a transition metal compound, such as a transition metal halide or alkoxide, like titanium tetrachloride or vanadium (V) trichloride oxide, to form discrete catalyst particles. The catalyst particles are used in conjunction with a suitable cocatalyst, like triethylaluminum, in the homopolymerization or copolymerization of 1-olefins. During polymerization, porous biodegradable catalyst particles are fragmented into small solid particles that are trapped within polymer.

Abstract: A multiple site solid catalyst component capable of producing polyolefins having a broad or multimodal molecular weight distribution, such as a bimodal molecular weight distribution, is prepared by contacting a particulate solid support with a zirconium compound or complex to bind the zirconium compound or complex to the support, optionally followed by contacting the supported zirconium compound or complex with a Lewis acid to produce an intermediate product, optionally isolating and washing the supported zirconium compound or complex or resulting intermediate product to remove soluble by-products therefrom, and reacting the washed or unwashed supported zirconium compound or complex or intermediate product with a titanium or vanadium compound to produce a solid catalyst component.