Patents by Inventor David J. Mitchell

David J. Mitchell 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).

  • Reduction of isomerization in solution process for polymerization of alpha-olefins
    Patent number: 4701504
    Abstract: A solution polymerization process for the preparation of high molecular weight polymers of alpha-olefins selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and C.sub.4 -C.sub.12 alpha-olefins is disclosed. The process comprises feeding monomer(s), coordination catalyst and inert hydrocarbon solvent to a reactor, polymerizing the monomers at a temperature of up to 320.degree. C. and a pressure of less than 25 MPa, and deactivating the catalyst in the solution so obtained. The catalyst is deactivated by sequentially admixing therewith a minor amount of a nitrogenous base, especially an aqueous solution of such a base, followed by a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The ratio of water:nitrogenous base should not be greater than 5.
    Type: Grant
    Filed: January 23, 1986
    Date of Patent: October 20, 1987
    Assignee: Du Pont Canada Inc.
    Inventors: David J. Mitchell, Vaclav G. Zboril