Patents by Inventor Michael Patrick Farr

Michael Patrick Farr 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: 5675022
    Abstract: Processes are disclosed for the recovery of 1,4-dioxanone by melt crystallization from a feed containing impurities capable of initiating the polymerization of 1,4-dioxanone, e.g., diethylene glycol. The processes of the present invention utilize melt crystallization in a cyclic process involving the steps of (i) crystallizing the 1,4-dioxanone out of the feed at a temperature below its melting point and removing a liquid residue containing a higher concentration of impurities, (ii) partially melting the crystallized 1,4-dioxanone to further remove impurities and (iii) thereafter, melting the remaining crystallized 1,4-dioxanone and recovering the melted product. The crystallization process can be repeated as required to achieve the desired purity. The purity of the product obtained is typically 99.5 wt %, 1,4-dioxanone or higher. The purified 1,4-dioxanone is useful, for example, as a monomer in the production of polydioxanone.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: October 7, 1997
    Assignee: Union Carbide Chemicals & Plastics Technology Corporation
    Inventors: Charles Guthrie Moyers, Michael Patrick Farr