Univation Technologies, LLC

Union Carbide Chemicals & Plastics Technology Corporation

Union Carbide Corporation

Union Carbide Chemicals and Plastics Company, Inc.

Mark Gregory Goode

Kevin Joseph Cann

John H Moorhouse

John Francis Szul

Simon Mawson

Wesley R Mariott

Timothy R Lynn

Sun-Chueh Kao

Daniel Paul Zilker, Jr

Matthew Gary McKee

Ronald Steven Eisinger

Tae Hoon Kwalk

Clark Curtis Williams

Maria A Apecetche

Kersten Anne Terry

Robert J Jorgensen

Timothy Todd Wenzel

David H McConville

F David Hussein

John Henry Oskam

Robert Harold Vogel

Thomas Edward Spriggs

Kevin R Gross

Francois Alexandre

Dongming Li

Phuong Anh Cao

Thomas Oswald

William Albert Matthews

Ching-Tai Lue

Jose Fernando Cevallos-Candau

Cliff Robert Mure

Robert Darrell Olson

Francis Charles Rix

Chi-I Kuo

David James Schreck

Michael E Muhle

C Jeff Harlan

Leonard Sebastian Scarola

Duan-Fan Wang

Robert Lorenz Boysen

Minghui Zhang

Gary Harry Williams

Robert Cecil Brown

John Henry Moorhouse

Barbara J Kopp

Robert Olds Hagerty

Richard B Pannell

John Roberts Parrish

Kersten Anne Erickson

Paul T Daniell

Frederick John Karol

Agapios Kyriacos Agapiou

Bruce Jon Savatsky

Kiu H Lee

Garth Ronald Giesbrecht

Timothy Marlow Boller

R Eric Pequeno

Ping P Cai

Arthur E Marcinkowsky

Robert Converse Brady, Iii

Michael A Kinnan

Mark Williams Blood

Stephen Paul Jaker

Kefu Sun

Bo Liu

Robert J Bernier

C Dale Lester

James Leland Swecker, Ii

Abarajith S Hari

Natarajan Muruganandam

Thomas James McNeil

Jody Michael Moffett

Eugene H Theobald

Charles D Lester

Gregory George Smith

Gregory T Whiteker

Rainer Kolb

James McLeod Farley

Fathi David Hussein

Mark Bradley Davis

Lixin Sun

Fred David Ehrman

Stefan B Ohlsson

Ayush A Bafna

James D McCullough, Jr

William George Sheard

Isaac Jacob Levine

Robert Lynn Santana

Maria Pollard

Arakalgud V Ramamurthy

George W Schwarz, Jr

Laurence G Britton

Ian D Burdett

Jeffrey Brian Drabish

Parul A Khokhani

Dale A Wright

François Alexandre

Billy Jack Garner

Eric Lucas

Timothy Joseph Howley

Embodiments of the present disclosure are directed towards method for modifying a polymer flow index. As an example, a method for modifying a polymer flow index can include providing monomers to a polymerization reactor, providing a chromium catalyst to the polymerization reactor, and providing an active amount of a flow index modifier to the polymerization reactor, wherein the flow index modifier is selected from carbon dioxide, carbon monoxide, 2,4-hexadiene, and combinations thereof.

Polymer flow index modifier

Polymerization process control methods for making polyethylene are provided. The process control methods include performing a polymerization reaction in a polymerization reactor to produce the polyethylene, where ethylene, and optionally one or more comonomers, in the polymerization reaction is catalyzed by an electron donor-free Ziegler-Natta catalyst and an alkyl aluminum co-catalyst. A melt flow ratio (I/I) of the polyethylene removed from the polymerization reactor is measured and an amount of long chain branching (LCB) of the polyethylene from the polymerization reactor is controlled by adjusting a weight concentration of the alkyl aluminum co-catalyst present in the polymerization reactor. In addition, an electron donor-free Ziegler-Natta catalyst productivity of the polyethylene being produced in the polymerization reactor is measured from which the amount of LCB of the polyethylene from the polymerization reactor is determined using the measured electron donor-free Ziegler-Natta catalyst productivity and a predetermined relationship between the electron donor-free Ziegler-Natta catalyst productivity and the LCB.

Process control for long chain branching control in polyethylene production

The present disclosure provides for a system and method for producing a polyethylene polymer (PE) that includes measuring a melt flow index (MFI) of the PE, comparing the measured value of the MFI to a predetermined desired range for the MFI, changing a catalyst feed rate to the polymerization reactor based on the compared values of the MFI, where changes in the catalyst feed rate preemptively compensate for subsequent changes in an oxygen flow rate to the polymerization reactor that maintain a predetermined residence time and bring the MFI of the PE into the predetermined desired range for the MFI; and changing the oxygen flow rate to the polymerization reactor thereby maintaining both the predetermined residence time and bringing the MFI of the PE into the predetermined desired range for the MFI. The measuring and comparing steps are repeated to ensure the measured value of the MFI is within the predetermined desired range of the MFI at the predetermined residence time.

Producing a polyethylene polymer

A system and method for charging a chromium-based catalyst to a mix vessel; introducing a reducing agent through an entrance arrangement into the mix vessel, and agitating a mixture of the chromium-based catalyst, the reducing agent, and a solvent in the mix vessel to promote contact of the reducing agent with the chromium-based catalyst to give a reduced chromium-based catalyst.

Polyolefin production with chromium-based catalysts

Disclosed herein are methods of controlling polymer properties in polymerization processes that use a chromium-based catalyst. An embodiment discloses a method of producing a polyolefin comprising: contacting a reaction mixture and a reduced chromium oxide catalyst in a gas-phase reactor to produce the polyolefin, wherein the reaction mixture comprises a monomer and a co-monomer; and changing a reaction temperature in the gas-phase reactor by about 1&#xb0; C. or more whereby a gas molar ratio of the co-monomer to the monomer is changed by about 2% or more and a co-monomer content of the polyolefin at substantially constant density is changed by about 2% or more. Additional methods and compositions are also provided.

Methods for controlling polymer properties

Embodiments of the present disclosure are directed towards methods for rating polymerization processes based upon a first cracking index value and a second cracking index value.

Rating polymerization processes

An ethylene/alpha-olefin copolymer that can be synthesized in a fluidized-bed, gas phase polymerization reactor and made into a blown film. The ethylene/alpha-olefin copolymer is characterized by a bubble stability-effective combination of properties comprising density, melt flow ratio ('I/I'), and melt storage modulus G' (G&#x2033;=3,000 Pa). The synthesis in the FB-GPP reactor is characterized by a property-imparting-effective combination of operating conditions comprising reactor bed temperature and H2/C2 gas molar ratio. An embodiment of the blown film consisting of the ethylene/alpha-olefin copolymer is characterized by enhanced bubble stability. A method of making the ethylene/alpha-olefin copolymer. A film comprising the ethylene/alpha-olefin copolymer. A method of making the film. A manufactured article comprising the film.

Polyethylene copolymer resins and films

A method of selectively transitioning a polymerization process making an ethylene/alpha-olefin copolymer in such a way that melt elasticity of the copolymer is substantially changed without changing comonomer and without substantially changing density of the copolymer. A method of compensating a reactor temperature-induced change in melt elasticity with an inverse change in H2/C2 gas molar ratio. Also, use of process control variable(s) to selectively change the melt elasticity.

Selectively transitioning polymerization processes

A film formed from a polyethylene copolymer using a reduced chromium oxide catalyst, ethylene monomers and a co-monomer selected from butene monomers or 1-hexene, where the polyethylene copolymer has a density in the range of from about 0.935 to about 0.950 g/cmand an I/Iin a range of about 18.0 to about 30.0. The film formed from the polyethylene copolymer has a dart drop impact (g/&#x3bc;m) that significantly greater as compared to a film of the polyethylene copolymer formed using a silyl chromate catalyst in place of the reduced chromium oxide catalyst. A method of making such films is also provided.

Polyolefin film with improved toughness

A method including contacting a chromium-based catalyst with a reducing agent in a solvent to lower an oxidation state of at least some chromium in the chromium-based catalyst to give a reduced chromium-based catalyst, drying the reduced chromium-based catalyst at a temperature, and adjusting the temperature to affect the flow index response of the reduced chromium-based catalyst.

A system and method for feeding a chromium-based catalyst to a polymerization reactor; adding a reducing agent to the chromium-based catalyst, and polymerizing an olefin into a polyolefin in the polymerization reactor in the presence of the chromium-based catalyst.

Polymerization process control methods for making polyethylene are provided. The process control methods include performing a polymerization reaction in a polymerization reactor to produce the polyethylene, where ethylene, and optionally one or more comonomers, in the polymerization reaction is catalyzed by an electron donor-free Ziegler-Natta catalyst and an alkyl aluminum co-catalyst. A melt flow ratio (I/I) of the polyethylene removed from the polymerization reactor is measured and an amount of long chain branching (LCB) of the polyethylene from the polymerization reactor is controlled by adjusting a weight concentration of the alkyl aluminum co-catalyst present in the polymerization reactor. In addition, an electron donor-free Ziegler-Natta catalyst productivity of the polyethylene being produced in the polymerization reactor is measured from which the amount of LCB of the polyethylene from the polymerization reactor is determined using the measured electron donor-free Ziegler-Natta catalyst productivity and a predetermined relationship between the electron donor-free Ziegler-Nana catalyst productivity and the LCB.

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Hurricane, WV, United States of America

Mark Gregory Goode