Patents by Inventor David J. Freeman

David J. Freeman 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).

  • Polymeric Materials
    Publication number: 20080214726
    Abstract: Copolymers, desirably having a molecular weight of from 500 to 20000, of aminoesters or aminoamides of (meth)acrylic acid and (meth)acrylamides at a molar ratio of from 10:1 to 60:1, particularly from 12:1 to 50:1 and especially about 20:1, can act as gas hydrate inhibitors in water containing hydrocarbon gas streams. Desirably the aminoesters or aminoamides are N-alkyl-amino(esters or amides) in particular of the formula (I): H2C?CR1 C(O)XR2NR3R4 (I) where R1, R2, R3, R4 and X have defined meanings and the (meth)acrylamides are of the formula (II): H2C?CR6C(O)NR7R8 (II) where R6, R7 and R8 have defined meanings. Methods of treating gas water mixtures using the copolymers to inhibit gas hydrate formation are described.
    Type: Application
    Filed: November 2, 2005
    Publication date: September 4, 2008
    Applicant: Croda International Plc
    Inventors: David J. Freeman, Derek J. Irvine, Jane Kitching, Stephen C. Rogers