Patents by Inventor Laurence W. Chang

Laurence W. Chang 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).

  • Substituted urea and oxime modified amino crosslinking agents, curable compositions containing the same and process for preparing pyrrolidone urea
    Patent number: 5665852
    Abstract: Novel substituted urea and oxime carbamate modified amino crosslinking agents, curable compositions containing the same, including curable powder coating compositions, are disclosed. Also disclosed is a novel process for preparing pyrrolidone urea.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 9, 1997
    Assignee: Cytec Technology Corp.
    Inventors: Balwant Singh, Laurence W. Chang, Larry S. Anderson, Stephen F. Donovan
  • Surface-modified polyacrylonitrile beads
    Patent number: 5418284
    Abstract: A bead composition is disclosed herein which comprises a core of a polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: May 23, 1995
    Assignee: Cytec Technology Corp.
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile fibrous substrates
    Patent number: 5306782
    Abstract: A surface-modified fibrillated fiber composition is disclosed herein which comprises polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: April 26, 1994
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile fibrous substrates
    Patent number: 5284910
    Abstract: A surface-modified fibrillated fiber composition is disclosed herein which comprises polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: February 8, 1994
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile substrates
    Patent number: 5284911
    Abstract: A composition is disclosed herein which comprises a core of a polyacrylonitrile homopolymer or copolymer and a surface of N-haloamides. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: November 18, 1992
    Date of Patent: February 8, 1994
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile fibrous substrates
    Patent number: 5270384
    Abstract: A surface-modified fibrillated fiber composition is disclosed herein which comprises polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: June 8, 1992
    Date of Patent: December 14, 1993
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile beads
    Patent number: 5268421
    Abstract: A bead composition is disclosed herein which comprises a core of a polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: December 7, 1993
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile fibrous substrates
    Patent number: 5155174
    Abstract: A surface-modified fibrillated fiber composition is disclosed herein which comprises polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: July 13, 1990
    Date of Patent: October 13, 1992
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile beads
    Patent number: 5137983
    Abstract: A bead composition is disclosed herein which comprises a core of a polyacrylonitrile homopolymer or copolymer and a surface of pendant N-haloamide groups. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: August 11, 1992
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Surface-modified polyacrylonitrile substrates
    Patent number: 5082904
    Abstract: A composition is disclosed herein which comprises a core of a polyacrylonitrile homopolymer or copolymer and a surface of N-haloamides. Also disclosed is a process for the production of said composition.
    Type: Grant
    Filed: April 13, 1990
    Date of Patent: January 21, 1992
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Larry S. Anderson, David A. Ley
  • Preparation of primary aralkyl urethanes and ureas and isocyanates derived therefrom
    Patent number: 4879410
    Abstract: A process is disclosed for the preparation of aralkyl mono- and diurethanes or ureas by carbamylmethylation, or acid-catalyzed addition at a temperature of 40.degree. C. to about 100.degree. C. of formaldehyde and esters of carbamic acid to aromatic hydrocarbons. Aralkyl carbamates and ureas formed by this process can be cracked directly to produce aralkyl diisocyanates, or hydrogenated and then cracked to produce aliphatic diisocyanates, or reacted directly with polyols to produce polyurethanes by functioning as blocked isocyanates.
    Type: Grant
    Filed: November 3, 1986
    Date of Patent: November 7, 1989
    Assignee: American Cyanamid Company
    Inventors: Balwant Singh, Laurence W. Chang, William A. Henderson, Jr.
  • Substituted N-hydroxyphthalimides and their use as detergent additives
    Patent number: 4863636
    Abstract: N-hydroxyimide compounds derived from substituted phthalic anhydride are provided which exhibit strong metal ion chelating ability, making them useful as detergent additives, in boiler water systems, as reaction intermediates, etc. A detergent composition containing N-hydroxyimide and/or carboxy hydroxamic acid detergent additives is also disclosed.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: September 5, 1989
    Assignee: American Cyanamid Company
    Inventors: Laurence W. Chang, Robert G. Fischer
  • Urethanes from tertiary aralkyl diols
    Patent number: 4570012
    Abstract: Production of tertiary aralkyl urethanes, such as tetramethyl xylylene diurethanes, by addition of corresponding diols and carbamic acid esters at moderate temperatures and in the presence of acid catalyst.
    Type: Grant
    Filed: February 24, 1984
    Date of Patent: February 11, 1986
    Assignee: American Cyanamid Co.
    Inventors: Balwant Singh, Peter S. Forgione, Laurence W. Chang
  • Tertiary aralkyl urethanes and isocyanates derived therefrom
    Patent number: 4439616
    Abstract: Production of tertiary aralkyl isocyanates, such as tetramethyl xylylene diisocyanates, by thermal cracking of corresponding urethanes formed by addition of corresponding olefins and carbamic acid esters at moderate temperatures and in the presence of acid catalyst.
    Type: Grant
    Filed: July 22, 1982
    Date of Patent: March 27, 1984
    Assignee: American Cyanamid Company
    Inventors: Balwant Singh, Laurence W. Chang, Peter S. Forgione
  • Manufacture of isocyanates
    Patent number: 4379767
    Abstract: A process for the production of tertiary benzyl isocyanates by reaction of the corresponding olefin with a carbamoyl halide to form the benzyl halide followed by the reaction of the benzyl halide with an excess of isocyanic acid to form the isocyanate and carbamoyl halide which can be recovered and recycled.
    Type: Grant
    Filed: March 8, 1982
    Date of Patent: April 12, 1983
    Assignee: American Cyanamid Company
    Inventors: Vazken A. Alexanian, Peter S. Forgione, Laurence W. Chang