Patents by Inventor William A. St. Laurent

William A. St. Laurent 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).

  • Recovery of cyclic arylene sulfide oligomers
    Patent number: 5440009
    Abstract: A method for recovering cyclic oligomers from a poly(arylene sulfide) polymer or poly(arylene sulfide) polymerization reaction mixture is provided in which the cyclic oligomers are maintained in a solution comprising a suitable solvent and the cyclic oligomers; then the solution is contacted with water to cause the formation of a suspension; then the suspension is acidified to cause the flocculation of cyclic oligomers which can then be more easily recovered.
    Type: Grant
    Filed: December 30, 1993
    Date of Patent: August 8, 1995
    Assignee: Phillips Petroleum Company
    Inventors: Carlton E. Ash, William A. St. Laurent