Patents Assigned to Polywood Inc.
  • Use of recycled plastics for preparing high performance composite railroad ties
    Patent number: 6191228
    Abstract: A method of maintaining proper distance between railroad rails is disclosed. The method utilizes railroad ties manufactured from a composite of polystyrene and polyolefin components, preferably obtained from recycled plastics. The composite exhibits a dual phase morphology wherein the two phases, polystyrene and polyolefin, intertwine and remain continuous throughout the material.
    Type: Grant
    Filed: January 27, 1999
    Date of Patent: February 20, 2001
    Assignee: Polywood Inc.
    Inventors: Thomas Nosker, Richard Renfree, James Kerstein