Equistar Chemicals, LP

Quantum Chemical Corporation

Mark K Reinking

Douglas D Klendworth

Karen E Meyer

Harilaos Mavridis

Albert P Masino

Raghu K Menon

Joel A Mutchler

Michael W Lynch

Charles S Holland

Sameer D Mehta

Ramesh N Shroff

Kiran M Gupte

Keta M Lindstrom

Michael H Treptau

Francis M Mirabella

Edward D Kist

Karl P Rufener

Giampiero Morini

Shaotian Wang

Gregory G Hlatky

Joachim T M Pater

Andrew J Scheie

A process for making an ethylene homopolymer in the presence of an oxide-supported chromium catalyst is disclosed. A small amount of an &#x3b1;-olefin contacted with the catalyst before polymerizing ethylene or introduced into an ethylene homopolymerization unexpectedly boosts process productivity. When used at part per million levels, the &#x3b1;-olefin improves productivity while maintaining desirable polymer properties. The invention is particularly valuable for making HDPE resins useful for blow molding applications.

Process for making ethylene homopolymers

A method for preparing a titanium-containing Ziegler-Natta catalyst is disclosed. A dialkyl magnesium compound, a trialkyl aluminum compound, and a polymethylhydrosiloxane are first combined in a hydrocarbon solvent. That product is then combined with dry, alcohol-free magnesium chloride. A solid product from the reaction with the magnesium chloride component is isolated and washed with a hydrocarbon solvent. The washed solid product is then combined with an alkyl aluminum dichloride or a dialkyl aluminum chloride to give the catalyst. The catalyst is suitable for both slurry and gas-phase olefin polymerizations. Polyolefins produced with the catalyst have broad molecular weight distributions and narrow distributions of relatively large particles.

Method for preparing a Ziegler-Natta catalyst

A process for the copolymerization of ethylene and &#x3b1;-olefins which utilizes a mixed modifier comprised of a conjugated diene and alkoxysilane is disclosed.

Process for the production of ethylene copolymers

The invention relates to supports comprising inorganic oxide particles coated with magnesium chloride and a method for making them. The inorganic oxide has a mean particle diameter of less than 5 microns and is used as a seed to crystallize magnesium chloride from solution. The magnesium chloride-coated inorganic oxide is useful for supporting transition metal compounds; the supported transition metal compounds are used as catalysts for polymerizing olefins.

Magnesium chloride support

A method of modifying a polyethylene is disclosed. In the method ethylene or a mixture of ethylene and a C3-C10 &#x3b1;-olefin is polymerized in an organic solvent with a Ziegler or single-site catalyst to form an initial polyethylene solution. The initial polyethylene solution is then reacted with a free radical initiator to produce a modified polyethylene. The modified polymer has an enhanced melt elasticity and increased long chain branching index, and is essentially free of gel.

Modifying polyethylene made by Ziegler or single-site catalyst with free radical initiator

A method for modifying polyolefin-clay nanocomposites is disclosed. The method comprises shearing a melt of solution-prepared nanocomposites at an effective shear rate. The modified nanocomposite shows significantly decreased complex melt viscosity, storage modulus, and loss modulus.

Shear modification of polyolefin-clay nanocomposites

An improved two-step polymerization process wherein ethylene homopolymer is produced in a first reactor and ethylene copolymer having narrowed short-chain branching distribution is prepared in a second reactor. Narrowed short-chain branching distribution of the copolymer is achieved by including specific silane modifiers in the second reactor.

Process for narrowing short-chain branching distribution in two-step ethylene polymerizations and products

A clay-filled polyolefin composition and process for making it are disclosed. The process involves treatment of a non-acid-treated smectite clay with a Ziegler-Natta catalyst in the presence of a hydrocarbon and subsequent polymerization of an olefin in the presence of the treated clay and an organoaluminum cocatalyst. Results indicate that filled compositions produced by this process contain exfoliated clay.

Process for making polyolefin compositions containing exfoliated clay

A process for polymerizing ethylene is disclosed. A magnesium chloride-alcohol is used to support an organometallic complex comprising a Group 3 to 10 transition metal and an indenoindolyl ligand. The supported organometallic complex is mixed with an activator and ethylene and the ethylene is polymerized. Use of magnesium chloride containing an alcohol as the support provides an unexpected boost in catalyst activity and improves polymer rheological properties.

Olefin polymerization process

A process for polymerizing olefins is disclosed. The process uses a hydrosilane in a polymerization catalyzed by an open architecture, bridged indenoindolyl organometallic complex and an activator. Polyolefins from the process have increased molecular weight.

Hydrosilane additives for increased polyolefin molecular weight

A process for copolymerizing ethylene with vinylsilanes is disclosed. The process uses a Ziegler-Natta catalyst and cocatalyst wherein the Ziegler-Natta catalyst is prepared from a Group 4-6 halogen-containing transition metal and a mixture of an organomagnesium compound and a silicon-containing compound. Silane-functionalized polyolefins produced using the process can be crosslinkable and can be used to bond polyolefins to polysiloxanes or other functionalized polymers.

Process for copolymerizing ethylene with vinylsilanes

A method for modifying a high-density polyethylene (HDPE)-clay nanocomposite is disclosed. The method comprises shearing a melt of the nanocomposite at an effective shear rate. The modified nanocomposite shows significantly increased complex melt viscosity, storage modulus, and loss modulus.

Shear modification of HDPE-clay nanocomposites

A method for producing propylene polymers having a broad molecular weight distribution (MWD) is disclosed. The method uses a Ziegler catalyst and one silane donor. The silane donor is selected from vinyltrimethoxysilane or dicyclohexyldimethoxysilane. The polymers made by the method have an MWD greater than or equal to 7.0.

Method for preparing propylene polymers having broad molecular weight distribution

A polyethylene having improved rheological properties is disclosed. The polyethylene has a melt index (MI ) from about 0.01 dg/min to about 50 dg/min and a melt strength (&eegr;) that satisfies MI &times;&eegr;&gE;3.5. A process for making the polyethylene is also disclosed. The process uses an azaborolinyl-containing single-site catalyst in the presence of hydrogen, where the hydrogen consumption is controlled to be less than 30%.

Preparation of polyethylene

The present invention provides an ethylene copolymer resin that has unique melt elastic properties not observed in ethylene copolymers heretofore known. Specifically, the ethylene copolymer resin of the present invention when in pelletized form has a reduction in melt elasticity (ER) of 10% or more to a final value of 1.0 or less upon rheometric low shear modification or solution dissolution. Moreover, the resin of the present invention when in reactor-made form exhibits at least a partially reversible increase of 10% or more in ER when pelletizing the same. An ethylene polymerization catalyst, a process of preparing the ethylene copolymer resin and a high-impact film are also provided herein.

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Mason, OH, United States of America

Mark K Reinking