Patents by Inventor Mark T. Nemeth

Mark T. Nemeth 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).

  • Patent number: 5502129
    Abstract: Solutions of triorganotin lithium are described having low residual concentrations (preferably less than 2,000 ppm) of halide. These are produced by a two-step process.Triorganotin halide is reacted with lithium to produce hexaorgano ditin and a precipitate of lithium halide. The lithium halide precipitate is removed by filtration and/or use of highly concentrated reaction conditions. Then the hexaorgano ditin is further reacted with lithium to form the triorgano substituted tin lithium. The lithium halide is less soluble in hot tetrahydrofuran (THF) and/or more concentrated solutions. THF is a preferred solvent for the reaction. The low-temperature reactions described result in low amounts of inactive and/or undesirable byproducts. These triorganotin lithium compounds are useful as anionic initiators that result in polymers with terminal tin compounds, e.g., triorganotin, attached to the terminal end of the polymer where initiation occurred.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: March 26, 1996
    Assignees: Bridgestone Corporation, Cyprus Foote Mineral Co.
    Inventors: William L. Hergenrother, W. Novis Smith, Anthony J. Muratore, III, Jay C. Sigle, Mark T. Nemeth