Patents by Inventor Yu-sung Jung

Yu-sung Jung 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).

  • Patent number: 8299175
    Abstract: Disclosed is a method for preparing a thermoplastic resin with superior impact resistance, chemical resistance and processability as well as excellent gloss and whiteness. The method includes emulsion-polymerizing a conjugated diene compound monomer to prepare a rubber latex having an average particle diameter of 1,800 ? to 5,000 ?, a polymerization conversion ratio of at least 90% and a swelling index of 12 to 40, an average gel content of 70 to 95%, emulsion-polymerizing 45 to 75 parts by weight of the rubber latex with 17 to 40 parts by weight of an aromatic vinyl compound and 4 to 20 parts by weight of a vinyl cyanide compound to prepare a graft copolymer latex, and coagulating the graft copolymer latex with a coagulant at 60 to 80° C., and aging the graft copolymer latex at 80 to 99° C. to obtain a graft copolymer powder.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: October 30, 2012
    Assignee: LG Chem, Ltd.
    Inventors: Keun-hoon Yoo, Chan-hong Lee, Jin-hyoung Lee, Joo-byung Chai, Yu-sung Jung, Bong-keun Ahn, Won-deok Han
  • Publication number: 20090118393
    Abstract: Disclosed is a method for preparing a thermoplastic resin with superior impact resistance, chemical resistance and processability as well as excellent gloss and whiteness. The method includes emulsion-polymerizing a conjugated diene compound monomer to prepare a rubber latex having an average particle diameter of 1,800 ? to 5,000 ?, a polymerization conversion ratio of at least 90% and a swelling index of 12 to 40, an average gel content of 70 to 95%, emulsion-polymerizing 45 to 75 parts by weight of the rubber latex with 17 to 40 parts by weight of an aromatic vinyl compound and 4 to 20 parts by weight of a vinyl cyanide compound to prepare a graft copolymer latex, and coagulating the graft copolymer latex with a coagulant at 60 to 80° C., and aging the graft copolymer latex at 80 to 99° C. to obtain a graft copolymer powder.
    Type: Application
    Filed: November 5, 2008
    Publication date: May 7, 2009
    Applicant: LG Chem, Ltd.
    Inventors: Keun-hoon Yoo, Chan-hong Lee, Jin-hyoung Lee, Joo-byung Chai, Yu-sung Jung, Bong-keun Ahn, Won-deok Han
  • Publication number: 20060079649
    Abstract: The present invention relates to a method for preparing rubber latex. The method of the present invention is characterized in that hard polymer seed is fed into a polymerization reactor equipped with a condenser before the commencement of polymerization and that the condenser is operated from the start of the polymerization, so that the condensate containing the conjugated diene compound is fed into the polymerization reactor with the commencement of the polymerization. In accordance with the method for preparing rubber latex of the present invention, it is possible to prepare core-shell type rubber latex capable of maximizing surface grafting ratio of rubber latex without sacrificing uniformity of polymerization system and particle stabilization and prepare resin having superior impact resistance, coloring property and appearance property(luster), when applied to ABS resins.
    Type: Application
    Filed: June 21, 2005
    Publication date: April 13, 2006
    Inventors: Yu-sung Jung, Dong-jin Park, Keun-hoon Yoo, Chan-hong Lee