Patents by Inventor Israel D. Fridman

Israel D. Fridman 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 the production of water-absorbing compositions
    Publication number: 20020086956
    Abstract: A process for producing a copolymer of an &agr;,&bgr;-unsaturated monomer having at least one pendant unit selected from a carboxylic acid group and derivatives thereof, and a copolymerizable monomer is described in which the process is carried out in a single solvent which is particularly an aromatic solvent. Processes of controlling the reaction and the particle size of the polymer produced are also described.
    Type: Application
    Filed: November 9, 2001
    Publication date: July 4, 2002
    Inventors: Israel D. Fridman, John C. Lamont, Ervin Dan
  • Process for the production of water-absorbing compositions
    Patent number: 6316554
    Abstract: A process for producing a copolymer of an a, &bgr;-unsaturated monormer having at least one pendant unit selected from a carboxylic acid group and derivatives thereof, and a copolymersable monomer is described in which the process is carried out in a single solvent which is particularly an aromatic solvent. Processes of controlling the reaction and the particle size of the polymer produced are also described.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: November 13, 2001
    Assignee: Camelot Superabsorbents Limited
    Inventors: Israel D. Fridman, John C. Lamont, Ervin Dan
  • Lactide polymerization
    Patent number: 5357034
    Abstract: High molecular weight polylactic acid is generally produced by the polymerization of lactide. Lactide is prepared by the depolymerization of low molecular weight polylactic acid. There are difficulties in the preparation of high molecular weight polylactic acid and high purity lactide isomers due to the equilibrium between lactic acid, low molecular weight polylactic acid, high molecular weight polylactic acid, lactide and water. Further it has never been proposed to provide a continuous process to produce high molecular weight polylactic acid from lactic acid. The present invention overcomes the equilibrium problem and provides a continuous process.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: October 18, 1994
    Assignee: Camelot Technologies Inc.
    Inventors: Israel D. Fridman, John Kwok, Ronald J. Downey, Speros P. Nemphos
  • Lactide melt recrystallization
    Patent number: 5264592
    Abstract: Generally, polylactic acid is prepared by the ring opening polymerization of lactide. However, to obtain a high molecular weight polylactic acid it is necessary to start with a lactide having a high degree of purity. Lactide may be economically brought to the required degree of purity using melt recrystallization techniques.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: November 23, 1993
    Assignee: Camelot Technologies Inc.
    Inventors: Israel D. Fridman, John Kwok
  • Continuous lactide polymerization
    Patent number: 5136017
    Abstract: Lactide monomers and copolymers may be polymerized by a continuous process using one or more continuous stirred tank reactors. The process offers productivity and product quality advantages over the batch process of polymerization.
    Type: Grant
    Filed: February 22, 1991
    Date of Patent: August 4, 1992
    Assignee: Polysar Financial Services S.A.
    Inventors: Gregory B. Kharas, Israel D. Fridman, Speros P. Nemphos