Patents Represented by Attorney J. Ward

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  • Preparation of insoluble polyvinylpyrrolidone
    Patent number: 4139688
    Abstract: Insoluble cross-linked homopolymers of vinylpyrrolidone or copolymers of vinylpyrrolidone are prepared by reaction of the soluble homopolymer or copolymer with certain acid chlorides at a temperature between 75.degree. C. and about 140.degree. C., to obtain a precipitate. Alternately, the insoluble product may be prepared by heating a partial amide chloride of a homopolymer or copolymer of vinylpyrrolidone.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: February 13, 1979
    Assignee: GAF Corporation
    Inventor: Kenneth W. Dixon