Patents by Inventor Douglas Radtke

Douglas Radtke 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).

  • Process for making an acrylic monomer having one or more quaternary ammonium groups and its polymers
    Patent number: 7858722
    Abstract: A method for making a monomer having an ethylenically unsaturated group and two or more quaternary ammonium groups per molecule, comprising: (a) reacting an excess of a monomeric reactant having at least one ethylenically unsaturated group and at least one tertiary amino group per molecule with a halohydroxyalkyl(trialkyl)quaternary ammonium salt, in an aqueous medium, (b) monitoring the pH of the aqueous medium from at least as early as the time when all reactants have been added to aqueous medium until completion of the reaction, and (c) adjusting the pH of the aqueous medium to and maintaining the pH of the aqueous medium at a value greater than or equal to 9, from the time, after all reactants have been added to aqueous medium, that the reaction mixture exhibits an apparent pH minimum until completion of the reaction.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: December 28, 2010
    Assignee: Rhodia Inc.
    Inventors: Leo Zhaoqing Liu, Jon D. Kiplinger, Douglas Radtke
  • Process for making an acrylic monomer having one or more quaternary ammonium groups and its polymers
    Publication number: 20080234432
    Abstract: A method for making a monomer having an ethylenically unsaturated group and two or more quaternary ammonium groups per molecule, comprising: (a) reacting an excess of a monomeric reactant having at least one ethylenically unsaturated group and at least one tertiary amino group per molecule with a halohydroxyalkyl(trialkyl)quaternary ammonium salt, in an aqueous medium, (b) monitoring the pH of the aqueous medium from at least as early as the time when all reactants have been added to aqueous medium until completion of the reaction, and (c) adjusting the pH of the aqueous medium to and maintaining the pH of the aqueous medium at a value greater than or equal to 9, from the time, after all reactants have been added to aqueous medium, that the reaction mixture exhibits an apparent pH minimum until completion of the reaction.
    Type: Application
    Filed: March 19, 2008
    Publication date: September 25, 2008
    Inventors: Leo Zhaoqing Liu, Jon D. Kiplinger, Douglas Radtke