Patents by Inventor Robert S. Cardwell

Robert S. Cardwell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6916883
    Abstract: A new process of interpolymerizing ethylene interpolymer products having improved properties, such as increased onset of crystallization temperature, is disclosed. Preferably, the process comprises interpolymerizing a first homogeneous ethylene/alpha-olefin interpolymer and at least one second homogeneous ethylene/alpha-olefin interpolymer using at least two constrained geometry catalysts having different reactivities such that the first ethylene/alpha-olefin interpolymer has a narrow molecular weight distribution (NMWD) with a very high comonomer content and relatively high molecular weight and the second ethylene/alpha-olefin interpolymer has a NMWD with a low comonomer content and a molecular weight lower than that of the first interpolymer. The resultant first homogeneous interpolymer is combined with the resultant second homogeneous interpolymer in appropriate weight ratios resulting in the desired finished polymer structure.
    Type: Grant
    Filed: September 1, 2004
    Date of Patent: July 12, 2005
    Assignee: Dow Global Technologies Inc.
    Inventors: Deepak R. Parikh, Brian W. S. Kolthammer, Robert S. Cardwell
  • Publication number: 20030166784
    Abstract: A new process of interpolymerizing ethylene interpolymer products having improved properties, such as increased onset of crystallization temperature, is disclosed. Preferably, the process comprises interpolymerizing a first homogeneous ethylene/alpha-olefin interpolymer and at least one second homogeneous ethylene/alpha-olefin interpolymer using-at least two constrained geometry catalysts having different reactivities such that the first ethylene/alpha-olefin interpolymer has a narrow molecular weight distribution (NMWD) with a very high comonomer content and relatively high molecular weight and the second ethylene/alpha-olefin interpolymer has a NMWD with a low comonomer content and a molecular weight lower than that of the first interpolymer. The resultant first homogeneous interpolymer is combined with the resultant second homogeneous interpolymer in appropriate weight ratios resulting in the desired finished polymer structure.
    Type: Application
    Filed: January 20, 2003
    Publication date: September 4, 2003
    Inventors: Deepak R. Parikh, Robert S. Cardwell, Brian W. S. Kolthammer
  • Publication number: 20030149181
    Abstract: Film, molded articles and fibers prepared from ethylene/&agr;-olefin interpolymer compositions are disclosed. The interpolymer compositions are blends prepared by combining specified amounts of a narrow molecular weight distribution, narrow composition distribution breadth index interpolymer, and a broad molecular weight distribution, broad composition distribution breadth index interpolymer, with each blend component having a specified density, melt index and degree of branching.
    Type: Application
    Filed: September 6, 2002
    Publication date: August 7, 2003
    Inventors: Brian W.S. Kolthammer, Robert S. Cardwell, Ronald P. Markovich, Bharat I. Chaudhary, Adam E. Laubach, Jesus Nieto
  • Patent number: 6566446
    Abstract: A new process of interpolymerizing ethylene interpolymer products having improved properties, such as increased onset of crystallization temperature, is disclosed. Preferably, the process comprises interpolymerizing a first homogeneous ethylene/alpha-olefin interpolymer and at least one second homogeneous ethylene/alpha-olefin interpolymer using at least two constrained geometry catalysts having different reactivities such that the first ethylene/alpha-olefin interpolymer has a narrow molecular weight distribution (NMWD) with a very high comonomer content and relatively high molecular weight and the second ethylene/alpha-olefin interpolymer has a NMWD with a low comonomer content and a molecular weight lower than that of the first interpolymer. The resultant first homogeneous interpolymer is combined with the resultant second homogeneous interpolymer in appropriate weight ratios resulting in the desired finished polymer structure.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: May 20, 2003
    Assignee: Dow Global Technologies Inc.
    Inventors: Deepak R. Parikh, Robert S. Cardwell, Brian W. S. Kolthammer
  • Patent number: 6545088
    Abstract: Ethylene, an &agr;-olefin and, optionally, a diene monomer are polymerized in a process comprising the step of contacting (1) ethylene, (2) at least one C3-C20 aliphatic &agr;-olefin, (3) optionally, at least one C4-C20 diene, (4) a catalyst comprising (a) a metallocene complex, and (b) an activator, and (5) a solvent. The process is conducted in either a single reactor or in multiple reactors, the latter configured either in series or parallel. Solvent is removed from the polymer stream in an anhydrous, first stage solvent recovery operation such that the solids concentration of the product stream is increased by at least 100 percent. Additional solvent is removed in an anhydrous, second stage solvent recovery operation from the product of the first stage solvent recovery operation such that the solids concentration of the product stream is in excess of 65 weight percent.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: April 8, 2003
    Assignee: Dow Global Technologies Inc.
    Inventors: Brian W. S. Kolthammer, Robert S. Cardwell, Deepak R. Parikh, Morris S. Edmondson, Stanley W. Smith
  • Patent number: 6538070
    Abstract: A new process of interpolymerizing ethylene interpolymer products having improved properties, such as increased onset of crystallization temperature, is disclosed. Preferably, the process comprises interpolymerizing a first homogeneous ethylene/alpha-olefin interpolymer and at least one second homogeneous ethylene/alpha-olefin interpolymer using at least two constrained geometry catalysts having different reactivities such that the first ethylene/alpha-olefin interpolymer has a narrow molecular weight distribution (NMWD) with a very high comonomer content and relatively high molecular weight and the second ethylene/alpha-olefin interpolymer has a NMWD with a low comonomer content and a molecular weight lower than that of the first interpolymer. The resultant first homogeneous interpolymer is combined with the resultant second homogeneous interpolymer in appropriate weight ratios resulting in the desired finished polymer structure.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: March 25, 2003
    Assignee: Dow Global Technologies Inc.
    Inventors: Robert S. Cardwell, Brian W. S. Kolthammer, Deepak R. Parikh
  • Patent number: 6448341
    Abstract: Film, molded articles and fibers prepared from ethylene/&agr;-olefin interpolymer compositions are disclosed. The interpolymer compositions are blends prepared by combining specified amounts of a narrow molecular weight distribution, narrow composition distribution breadth index interpolymer, and a broad molecular weight distribution, broad composition distribution breadth index interpolymer, with each blend component having a specified density, melt index and degree of branching.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: September 10, 2002
    Assignee: The Dow Chemical Company
    Inventors: Brian W. S. Kolthammer, Robert S. Cardwell, Ronald P. Markovich, Bharat I. Chaudhary, Adam E. Laubach, Jesus Nieto
  • Patent number: 5869575
    Abstract: Processes for polymerizing ethylene/.alpha.-olefin interpolymer compositions are disclosed. The interpolymer compositions have a controlled composition and a controlled molecular weight distribution. The processes utilize a highly-efficient homogeneous catalyst composition in at least one reactor to produce a first interpolymer having a narrow composition distribution and a narrow molecular weight distribution, and a highly-efficient heterogeneous Ziegler catalyst in at least one other reactor. The reactors can be operated sequentially or separately, depending upon the desired product. The novel compositions have good optical properties (e.g., clarity and haze) and good physical properties (e.g., modulus, yield strength, toughness and tear). Useful products which can be formed from these compositions include film, molded articles and fiber.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: February 9, 1999
    Assignee: The Dow Chemical Company
    Inventors: Brian W. S. Kolthammer, Robert S. Cardwell
  • Patent number: 5844045
    Abstract: Processes for polymerizing ethylene/.alpha.-olefin interpolymer compositions are disclosed. The interpolymer compositions have a controlled composition and a controlled molecular weight distribution. The processes utilize a highly-efficient homogeneous catalyst composition in at least one reactor to produce a first interpolymer having a narrow composition distribution and a narrow molecular weight distribution, and a highly-efficient heterogeneous Ziegler catalyst in at least one other reactor. The reactors can be operated sequentially or separately, depending upon the desired product. The novel compositions have good optical properties (e.g., clarity and haze) and good physical properties (e.g., modulus, yield strength, toughness and tear). Useful products which can be formed from these compositions include film, molded articles and fiber.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: December 1, 1998
    Assignee: The Dow Chemical Company
    Inventors: Brian W. S. Kolthammer, Robert S. Cardwell
  • Patent number: 5763547
    Abstract: A supported catalyst composition comprising a complex of a Group 4 metal cyclopentadienyl derivative reacted with silica treated with an aluminoxane demonstrates improved reactivity, especially for incorporating long chain alpha-olefins and also shows improved resistance to catalyst poisoning. The supported catalyst composition is adapted to produce homogeneous polymers, copolymers, terpolymers, etc., for example, homogeneous polyethylene, homogeneous poly(ethylene-octene) copolymers and the like. The invention further includes the process of preparing the supported catalyst compositions and a process for preparing olefinic polymers using these catalyst compositions.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: June 9, 1998
    Assignee: The Dow Chemical Company
    Inventors: Brian W. S. Kolthammer, John C. Tracy, Robert S. Cardwell, Robert K. Rosen
  • Patent number: 5453410
    Abstract: An addition polymerization catalyst comprising a cationic complex of a Group 4 metal cyclopentadienyl derivative and an alumoxane shows improved resistance to catalyst poisons.
    Type: Grant
    Filed: September 2, 1993
    Date of Patent: September 26, 1995
    Assignee: The Dow Chemical Company
    Inventors: Brian W. S. Kolthammer, Robert S. Cardwell, John C. Tracy