Patents by Inventor Li S. Nieh

Li S. Nieh 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).

  • Method of producing prepolymers from hydroxyalkyl lignin derivatives
    Patent number: 5102992
    Abstract: A method of producing prepolymeric materials from lignin is disclosed. The method uses lignin which has been hydroxyalkyl modified, such that the lignin is substantially non-phenolic and solvent soluble and/or liquid. The modified lignin is reacted with materials which yield prepolymers which may be polymerized according to known methods to produce useful polymers.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: April 7, 1992
    Assignees: Center for Innovative Technology, Virginia Polytechnic Institute and State University
    Inventors: Wolfgang G. Glasser, Willer De Oliveira, Stephen S. Kelley, Li S. Nieh
  • Method of producing star-like polymers from lignin
    Patent number: 5066790
    Abstract: A method of producing prepolymeric materials from lignin is disclosed. The method uses lignin which has been hydroxyalkyl modified, such that the lignin is substantially non-phenolic and solvent soluble and/or liquid. The modified lignin is reacted with materials which yield prepolymers which may be polymerized according to known methods to produce useful polymers.
    Type: Grant
    Filed: January 4, 1990
    Date of Patent: November 19, 1991
    Assignees: Center for Innovative Technology, Virginia Polytechnic Institute and State University
    Inventors: Wolfgang G. Glasser, Willer De Oliveira, Stephen S. Kelley, Li S. Nieh
  • Method of producing prepolymers from hydroxyalkyl lignin derivatives
    Patent number: 4918167
    Abstract: A method of producing prepolymeric materials from lignin is disclosed. The method uses lignin which has been hydroxyalkyl modified, such that the lignin is substantially non-phenolic and solvent soluble and/or liquid. The modified lignin is reacted with materials which yield prepolymers which may be polymerized according to known methods to produce useful polymers.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: April 17, 1990
    Assignee: Center for Innovative Technology
    Inventors: Wolfgang G. Glasser, Willer De Oliveira, Stephen S. Kelley, Li S. Nieh