Patents by Inventor Douglas G. Powell

Douglas G. Powell 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).

  • Polycondensates which can be sterilized by .gamma.-radiation
    Patent number: 5382605
    Abstract: A thermoplastic molding composition resistant to the degradation induced by ionizing-radiation is disclosed. The composition contains an aromatic polycondensate and an agent which is a compound conforming structurally to formula (I) ##STR1## or which is a member selected from the group consisting of oligocarbonate, polycarbonate, copolycarbonate, polyestercarbonate and polyesters which contain structural units conforming to formula (Ia) ##STR2## wherein R.sup.1 to R.sup.10 and X are defined. The composition is suitable for the manufacture of shaped articles, especially articles useful in medical applications.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: January 17, 1995
    Assignees: Miles Inc., Bayer Aktiengesellschaft
    Inventors: Douglas G. Powell, Charles E. Lundy, Gerhard Fennhoff, Ralf Hufen, Klaus Kircher
  • Color-stable polycarbonate composition resistant to gamma-radiation
    Patent number: 5280050
    Abstract: A thermoplastic polycarbonate molding composition which is rendered resistant to deterioration induced by exposure to gamma radiation is disclosed. The composition is imparted an improved degree of color stability upon the incorporation of a minor amount of a poly(alkylene oxide) oligomer and a halogenated aromatic acid derivative therewith. In addition, the composition is characterized by its low initial color and the small change in its yellowness index after a waiting period of several weeks.
    Type: Grant
    Filed: May 19, 1992
    Date of Patent: January 18, 1994
    Assignee: Miles Inc.
    Inventors: Douglas G. Powell, Sivaram Kirshnan
  • Polycarbonate composition with reduced drip rate on burning
    Patent number: 5250635
    Abstract: A molding composition containing a blend of polycarbonate resin and a small amount of an aromatic dicyanate ester is disclosed. In comparison to the performance of the unmodified polycarbonate resin, the transparent composition of the invention exhibits a significantly reduced dripping rate upon burning. The composition is suitable for the preparation of thermoplastically molded articles.
    Type: Grant
    Filed: July 15, 1992
    Date of Patent: October 5, 1993
    Assignee: Miles Inc.
    Inventors: Douglas G. Powell, Sivaram Krishnan
  • Gamma radiation resistant polycarbonate composition
    Patent number: 5214078
    Abstract: A thermoplastic polycarbonate molding composition comprising a polycarbonate resin and a stabilizing agent is disclosed. Containing (i) a polyether polyol and (ii) an aromatic disulfide, the agent imparts to the composition improved resistance to gamma-radiation-induced color change. Articles molded from the composition of the invention are suitable for the preparation of gamma-radiation sterilizable medical equipment.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: May 25, 1993
    Assignee: Miles Inc.
    Inventors: Douglas G. Powell, Charles E. Lundy
  • Pigmented polycarbonate composition having high impact strength and good cosmetics
    Patent number: 5194495
    Abstract: A pigmented thermoplastic molding composition is disclosed comprising(i) about 90 to 98 percent of an aromatic polycarbonate,(ii) about 1 to 9 percent of ABS, and(iii) about 1 to 9 percent of a grafted olefinic copolymer which is a graft polymer of one or more unsaturated dicarboxylic acid or the anhydride of said acid on an olefinic copolymer backbone.The composition is noted to have good mechanical properties and the articles molded therefrom have good cosmetics.
    Type: Grant
    Filed: July 24, 1992
    Date of Patent: March 16, 1993
    Assignee: Miles Inc.
    Inventors: Charles E. Lundy, Douglas G. Powell, Sivaram Krishnan