Patents by Inventor Margaretha J. C. M. Koppes

Margaretha J. C. M. Koppes 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).

  • Polymer process
    Patent number: 5268429
    Abstract: An improved process for the production of linear block copolymers of vinylaromatic hydrocarbon and conjugated alkadiene comprises the coupling of living polymer chains containing at least one block of polymerized vinylaromatic hydrocarbon and at least one block of polymerized conjugated alkadiene wherein the coupling agent is an aromatic phosphonite.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: December 7, 1993
    Assignee: Shell Oil Company
    Inventors: Margaretha J. C. M. Koppes, Johannes A. Van Doorn, Judith J. B. Walhof
  • Process for production of alkadiene-based polymer of increased vinyl content
    Patent number: 5194535
    Abstract: An improved process for the production of conjugated alkadiene-based polymers of higher vinyl content employs as a structure modifier a compound of the formula ##STR1## wherein R is alkylene, R' alkyl and R" is hydrogen or hydrocarbyl.
    Type: Grant
    Filed: June 4, 1992
    Date of Patent: March 16, 1993
    Assignee: Shell Oil Company
    Inventors: Margaretha J. C. M. Koppes, Johannes C. M. van der Arend