Patents Represented by Law Firm Cushman Darby & Cushman IP Group of Pollsbury Madison & Sutro LLP
  • Process for the fractionation of polyoxyalkylene block copolymers
    Patent number: 5800711
    Abstract: A process for the fractionation of polyoxyalkylene block copolymers wherein the polydispersity of the polyether is reduced. The fractionation process, which removes lower molecular weight species such as polyoxyalkylene homopolymer, truncated polyoxyalkylene diblock polymers, or other reaction byproducts, comprises salt extraction and liquid phase separation to provide a product with a narrower molecular weight distribution, lower degree of unsaturation, and distinctly different physical characteristics compared to the starting material.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: September 1, 1998
    Assignee: MDV Technologies, Inc.
    Inventors: Lorraine E. Reeve, Michael G. Hinsberg