Patents by Inventor Stephan Rodewald

Stephan Rodewald 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: 6479601
    Abstract: This invention is based upon the unexpected discovery that certain catalyst systems which are comprised of (A) a transition metal compound selected from the group consisting of iron (II) compounds, iron (III) compounds, cobalt (II) compounds, cobalt (III) compounds, and nickel (II) compounds; (B) a ligand selected from the group consisting of certain azopyridines and certain iminopyridines; and (C) methylalumoxane can be used to catalyze the polymerization of diene monomers, such as 1,3-butadiene and isoprene, into polymers, such as high cis-1,4-polybutadiene rubber. Some representative examples of azopyridines that can be utilized in the catalyst systems of this invention include 2-phenylazopyridine, 4-methyl-2-phenylazopyridine, and 2,6-diphenylazopyridine. The subject invention more specifically discloses a process for synthesizing a polybutadiene rubber which comprises polymerizing 1,3-butadiene at a temperature which is within the range of about 10° C. to about 100° C.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: November 12, 2002
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: Michael Lester Kerns, Daniel Edward Bowen, III, Stephan Rodewald
  • Patent number: 6362292
    Abstract: Transition metal complexes suitable for use for the polymerization of olefins having Lewis Base functionality. Preferred groups are dienes having dialkylamino functionality. The complexes may suitably be supported by the use of the functionalized dienes to give transition metal complexes which in the presence of activators are particularly suitable for gas phase processes.
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: March 26, 2002
    Assignee: BP Chemicals Limited
    Inventors: Eliane Garcia, Ian Raymond Little, Stephan Rodewald
  • Patent number: 5495035
    Abstract: A process of preparing in high yield ansa-metallocene complexes and rac-ansa-metallocene complexes by reacting an ansa-bis-cyclopentadiene compound with a metal amide complex.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: February 27, 1996
    Assignee: University of Iowa Research Foundation
    Inventors: Richard F. Jordan, Stephan Rodewald, Gary M. Diamond