Patents by Inventor Tao C. Chang

Tao C. 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).

  • High performance epoxy resin modified by a polysulfide polymer derived from the heavy ends waste of chlorinated hydrocarbon production
    Patent number: 5466763
    Abstract: A process is disclosed for preparing a polysulfide-epoxy prepolymer and cured co-polymer using a heavy ends waste generated in chlorinated hydrocarbon production. The process comprises first distilling the heavy ends waste to form an enriched heavy ends waste with an ethylene dichloride content less than about 10% by weight. The enriched heavy ends waste is then reacted with an alkaline polysulfide within a temperature range of about 50.degree. C. to about 150.degree. C. to form a polysulfide polymer mixture. Next, between about 5 and about 300 parts of the polysulfide polymer mixture is co-reacted with a hundred parts by weight of an epoxy resin to form a polysulfide-epoxy prepolymer or a cured co-polymer if a curing agent is present.
    Type: Grant
    Filed: November 8, 1994
    Date of Patent: November 14, 1995
    Assignee: Formosa Plastics Corporation
    Inventors: Chester C. Lee, Tao C. Chang, Yung-Hui Huang
  • Process for manufacturing a polysulfide polymer from the heavy ends waste of chlorinated hydrocarbon production
    Patent number: 5432257
    Abstract: A process is disclosed for preparing a polysulfide polymer using a heavy ends waste generated in chlorinated hydrocarbon production. The process involves first pretreating the heavy ends waste by an enriching process to form an enriched heavy ends waste with an ethylene dichloride content less than 10% by weight. The enriched heavy ends waste is then reacted with alkaline polysulfide within a temperature range of 50.degree. C. to 150.degree. C. to form a polysulfide polymer.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: July 11, 1995
    Assignee: Formosa Plastics Corporation
    Inventors: Chester Lee, Tao C. Chang, Yung-Hui Huang