Patents by Inventor David N. Marks

David N. Marks 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).

  • Publication number: 20140275311
    Abstract: Disclosed are salt compositions of lysinol and dicarboxylic acids; and lysinol derived polymers including polyamide, polyimide, polyurea, cross-linked polyurea comprising urethane linkages, polyurea foams, cross-linked polyurea foams, and lysinol-epoxy thermoset.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: E I DU PONT DE NEMOURS AND COMPANY
    Inventors: DAVID N. MARKS, KENNETH GENE MOLOY, MARK A. SCIALDONE, MANXUE WANG
  • Patent number: 6509439
    Abstract: A process for producing polyamides from dinitriles and diamines in a continuous reaction using subsequent heating steps. In particular, the process involves contacting a dinitrile, a diamine, water, and optionally a catalyst to form a reaction mixture; heating the reaction mixture to a first elevated temperature of between about 180 to about 240° C., maintaining said temperature for about 0.10 to about 20 hours, and optionally controlling the pressure in this heating step by venting; heating the reaction mixture to a second elevated temperature of between about 250 to about 350° C., adding water to the reaction mixture before or after the second elevated temperature is reached, maintaining the pressure in the second heating step above atmospheric pressure by venting at least some of the water, and maintaining the second elevated temperature for a period of about 0.10 to about 10 hours; and recovering the polyamide.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: January 21, 2003
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Richard Allen Hayes, David N Marks, Maria Van Eijndhoven, Hari Babu Sunkara
  • Patent number: 6476181
    Abstract: Process for increasing the molecular weight of nylon 6 while reducing its content of caprolactam and other volatiles by a two-staged heating process.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: November 5, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Albert W. Alsop, David N. Marks
  • Patent number: 6437089
    Abstract: Process for making nylon 6 in which a feed stream containing a major portion of caprolactam and/or nylon 6 prepolymer and a minor portion of aminocapronitrile is fed to a multistage reactive distillation column in which the feed stream flows countercurrently to a steam stream.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: August 20, 2002
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Jeffrey D. Cohen, Stuart B. Fergusson, Ernest Keith Marchildon, David N. Marks, Ahmet Turgut Mutel
  • Patent number: 5292857
    Abstract: Nylon 66 polymer is prepared by condensation of a reaction mixture containing 1,8-diazacyclotetradecane-2,7-dione and nylon 66 salt and/or caprolactam.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: March 8, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David N. Marks
  • Patent number: 5270437
    Abstract: Polymers of aromatic diacids and 2-methylpentamethylenediamine are prepared in the presence of formic acid. The formic acid reduces the tendency of the 2-methylpentamethylenediamine to cyclize.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: December 14, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David N. Marks
  • Patent number: 5185427
    Abstract: Copolyamides are prepared by the non-catalytic polymerization of an omega-aminonitrile with a mixture of a diamine and a dicarboxylic acid. Not more than 40% by weight of the product is derived from the omega-aminonitrile.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: February 9, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David N. Marks
  • Patent number: 5185428
    Abstract: A copolyadipamide consisting essentially of between about 60 and about 99.5 mole percent hexamethyleneadipamide units and between about 0.5 and 40 mole percent pentamethyleneadipamide units, the copolyamide having an RV greater than about 25, and a melting point of greater than about 220.degree. C.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: February 9, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: James A. Hammond, Jr., David N. Marks
  • Patent number: 5162491
    Abstract: A copolyadiapamide consisting essentially of between about 60 and about 99.5 mole percent hexamethyleneadipamide units and between about 0.5 and 40 mole percent trimethylhexamethyleneadipamide units, the copolyamide having an RV greater than about 25, and a melting point of greater than about 220.degree. C.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: November 10, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: James A. Hammond, Jr., David N. Marks
  • Patent number: 5110900
    Abstract: A copolyadipamide consisting essentially of between about 60 and about 99.5 mole percent hexamethyleneadipamide units and between about 0.5 and 40 mole percent ethyltetramethyleneadipamide units, the copolyamide having an RV greater than about 5, and a melting point of greater than about 220.degree. C.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: May 5, 1992
    Assignee: E. I Du Pont de Nemours and Company
    Inventors: James A. Hammond, Jr., David N. Marks
  • Patent number: 5109104
    Abstract: High quality polyamides are prepared from a mixture of an omega-aminonitrile, an oxygenated phosphorous catalyst, and water. When the reactor temperature reaches about 200 degrees to about 260 degrees C. continuously adding water, and continuously removing water vapor and ammonia until 15 to 75 grams of water have been added per 100 grams of omega-aminonitile, and then stopping the water addition and continuing the reaction until a high molecular weight polyamide is obtained.
    Type: Grant
    Filed: October 4, 1990
    Date of Patent: April 28, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David N. Marks