Patents by Inventor Kerstine Rabas

Kerstine Rabas 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 the preparation of copolymers
    Patent number: 4722958
    Abstract: Process for the preparation of copolymers from acrylamide and acrylic or methacrylic acid, wherein to prepare 100 parts by weight of the copolymer, (A) 10-90 parts by weight of acrylamide, (B) 90-100 parts by weight of acrylic acid and/or methacrylic acid or of a salt thereof, (C) 0-40 parts by weight of another copolymerizable monomer and (D) 0-5 parts by weight of a copolymerizable crosslinking agent which has two or more olefinic double bonds are polymerized in an alcohol having 1-4 carbon atoms by precipitation polymerization such that 10-90% by weight of the alcohol, 10-90% by weight of the total amount of monomers (A), (B) and (C) together with 100% by weight of the crosslinker substance are initially mixed, polymerization is started with 10-100% by weight of the initiator and then the remainder of the solvent, monomers, crosslinking agent and initiator to make up to 100% is metered in, as individual components or as a mixture, after the polymerization has started.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: February 2, 1988
    Assignee: Cassella Aktiengesellschaft
    Inventors: Josef Sauer, Friedrich Engelhardt, Kerstine Rabas, Ulrich Karsunky, Wolfram Schidlo, Jochen M. Quack, Alwin K. Reng, Werner Skrypzak