Patents by Inventor Graham R. Lief

Graham R. Lief 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).

  • Process for reducing the light oligomer content of polypropylene oils
    Patent number: 9951158
    Abstract: Disclosed herein are dual catalyst compositions containing an unbridged metallocene compound, a bridged metallocene compound, a chemically-treated solid oxide, and an optional co-catalyst. These catalyst compositions can be used for the oligomerization of propylene to produce an oligomer product. For example, a heavy propylene oligomer can be recovered from the oligomer product, and the heavy propylene oligomer can be characterized by a high flash point and viscosity index, and a low pour point.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: April 24, 2018
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Graham R. Lief, Uriah J. Kilgore, Eric J. Haschke
  • Process for Reducing the Light Oligomer Content of Polypropylene Oils
    Publication number: 20180105478
    Abstract: Disclosed herein are catalyst systems containing an alpha-diimine nickel halide complex, a chemically-treated solid oxide, and an optional co-catalyst. These catalyst systems can be used to reduce the light oligomer content of propylene oligomer streams, for instance, by oligomerizing olefin feedstocks containing C6 to C27 propylene oligomers to produce oligomer compositions having higher molecular weights.
    Type: Application
    Filed: October 19, 2016
    Publication date: April 19, 2018
    Inventors: Graham R. Lief, Uriah J. Kilgore, Eric J. Haschke
  • Process for Reducing the Light Oligomer Content of Polypropylene Oils
    Publication number: 20180044446
    Abstract: Disclosed herein are dual catalyst compositions containing an unbridged metallocene compound, a bridged metallocene compound, a chemically-treated solid oxide, and an optional co-catalyst. These catalyst compositions can be used for the oligomerization of propylene to produce an oligomer product. For example, a heavy propylene oligomer can be recovered from the oligomer product, and the heavy propylene oligomer can be characterized by a high flash point and viscosity index, and a low pour point.
    Type: Application
    Filed: August 12, 2016
    Publication date: February 15, 2018
    Inventors: Graham R. Lief, Uriah J. Kilgore, Eric J. Haschke
  • Liquid propylene oligomers and methods of making same
    Patent number: 9732300
    Abstract: Disclosed herein are oligomerization processes using feedstocks containing propylene to produce an oligomer product, and methods for recovering a propylene oligomer from the oligomer product. The resultant propylene oligomer can be characterized by a Mn in a range from 250 to 10,000 g/mol, a viscosity index of at least 85, and a pour point in a range from ?5 to ?60° C.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: August 15, 2017
    Assignee: Chevron Phillipa Chemical Company LP
    Inventors: Uriah J. Kilgore, Graham R. Lief, Eric J. Haschke
  • High Melt Flow Polypropylene Homopolymers for Fiber Applications
    Publication number: 20170198413
    Abstract: Disclosed herein are high melt flow polypropylene homopolymers generally characterized by a melt flow rate ranging from 200 g/10 min to 3000 g/10 min, a ratio of Mw/Mn ranging from 2 to 5, and a peak melting point ranging from 138° C. to 151° C. These polypropylene homopolymers can be produced by catalyst systems containing a racemic ansa-bis(indenyl)zirconocene compound, an activator-support, and an organoaluminum co-catalyst.
    Type: Application
    Filed: January 12, 2016
    Publication date: July 13, 2017
    Inventors: Graham R. Lief, Eric J. Haschke
  • Liquid Propylene Oligomers and Methods of Making Same
    Publication number: 20170022439
    Abstract: Disclosed herein are oligomerization processes using feedstocks containing propylene to produce an oligomer product, and methods for recovering a propylene oligomer from the oligomer product. The resultant propylene oligomer can be characterized by a Mn in a range from 250 to 10,000 g/mol, a viscosity index of at least 85, and a pour point in a range from ?5 to ?60° C.
    Type: Application
    Filed: July 23, 2015
    Publication date: January 26, 2017
    Inventors: Uriah J. Kilgore, Graham R. Lief, Eric J. Haschke
  • System and method for deterring fouling in a polymerization reactor
    Patent number: 9353202
    Abstract: A catalyst composition may include a precontacted mixture of an olefin polymerization catalyst and an agent including an ammonium salt. The catalyst activity of the catalyst composition in the presence of water may be greater than if no ammonium salt were present in the catalyst composition. The ammonium salt may include a tetraalkylammonium salt, and the olefin polymerization catalyst may include a metallocene compound.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: May 31, 2016
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Albert P. Masino, Randall S. Muninger, Max P. McDaniel, Eric D. Schwerdtfeger, Qing Yang, Graham R. Lief
  • SYSTEM AND METHOD FOR DETERRING FOULING IN A POLYMERIZATION REACTOR
    Publication number: 20150259447
    Abstract: A catalyst composition may include a precontacted mixture of an olefin polymerization catalyst and an agent including an ammonium salt. The catalyst activity of the catalyst composition in the presence of water may be greater than if no ammonium salt were present in the catalyst composition. The ammonium salt may include a tetraalkylammonium salt, and the olefin polymerization catalyst may include a metallocene compound.
    Type: Application
    Filed: May 28, 2015
    Publication date: September 17, 2015
    Inventors: Albert P. Masino, Randall S. Muninger, Max P. McDaniel, Eric D. Schwerdtfeger, Qing Yang, Graham R. Lief
  • System and method for deterring fouling in a polymerization reactor
    Patent number: 9073029
    Abstract: A catalyst composition may include a precontacted mixture of an olefin polymerization catalyst and an agent including an ammonium salt. The catalyst activity of the catalyst composition in the presence of water may be greater than if no ammonium salt were present in the catalyst composition. The ammonium salt may include a tetraalkylammonium salt, and the olefin polymerization catalyst may include a metallocene compound.
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: July 7, 2015
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Albert P. Masino, Randall S. Muninger, Max P. McDaniel, Eric D. Schwerdtfeger, Qing Yang, Graham R. Lief
  • SYSTEM AND METHOD FOR DETERRING FOULING IN A POLYMERIZATION REACTOR
    Publication number: 20150087793
    Abstract: A catalyst composition may include a precontacted mixture of an olefin polymerization catalyst and an agent including an ammonium salt. The catalyst activity of the catalyst composition in the presence of water may be greater than if no ammonium salt were present in the catalyst composition. The ammonium salt may include a tetraalkylammonium salt, and the olefin polymerization catalyst may include a metallocene compound.
    Type: Application
    Filed: September 25, 2013
    Publication date: March 26, 2015
    Inventors: Albert P. Masino, Randall S. Muninger, Max P. McDaniel, Eric D. Schwerdtfeger, Qing Yang, Graham R. Lief