Equistar Chemicals, LP

Quantum Chemical Corporation

Lyondell Petrochemical Company

Leonard V Cribbs

Bradley P Etherton

Sandor M Nagy

John A Tyrell

Ramesh Krishnamurti

Michael W Lynch

Jean A Merrick-Mack

Mary K Cocoman

Philip J Garrison

Paula L Nygard

James H Meas

Raymond E Hoff

Mark P Mack

Linda N Winslow

Lawrence R Wallace

Danny L Wise

Shaotian Wang

Charles S Holland

Jia-Chu X Liu

Stephen M Imfeld

Karen E Meyer

Venki Chandrashekar

James Ronald Clark

Kelly L Williams

Everett O Lewis

An ethylene polymerization process is disclosed. Ethylene is polymerized in two slurry reaction zones with a C-Calpha-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.

Polyethylene process

Transition metal catalysts containing bidentate ligands and method of using and preparing same

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 C &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI 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 MI 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.

High molecular weight, medium density polyethylene

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 C -C &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI 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 MI 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.

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.

Method for preparation of boratabenzene derivatives

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 MI 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 MI 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.

Polyethylene blends and films

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.

Olefin polymerization catalysts containing indolyl-amido ligands

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.

Supported olefin polymerization catalysts

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&deg; C., while maintaining high catalyst activity.

Process for making polyolefins

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.

Olefin polymerization process

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;

Modified polysiloxane catalysts and a method of using the same

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.

Catalyst system containing reaction product of liquid silicone and

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.

Polymerization of .alpha.-olefins with transition metal catalysts based

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.

Growing community of inventors

Hamilton, OH, United States of America

Leonard V Cribbs