Patents by Inventor Chi Sham

Chi Sham 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: 6576715
    Abstract: The invention relates to a process for the production of a polyamide molded part from a polyamide composition comprising 0.01-5 wt. % polyamide-4.6 and 99.99-95 wt. % of a polyamide with a melting point that is lower than that of polyamide-4.6. The polyamide composition is obtained by mixing in the melt of a blend of granules of the polyamide with the low melting point (A) and a composition (B) of the polyamide-4.6 in the polyamide with the low melting point, the polyamide-4.6 content of (B) amounting to 2-50 wt. % and B having been obtained at a temperature above the melting point of polyamide-4.6. The polyamide with a low melting point is preferably polyamide-6. The process results in a permanent 15° C. increase in the crystallisation onset temperature of nylon-6. A 30% gain in cycle time relative to polyamide-6 nucleated with the aid of microtalc was realised for injection-molding of relatively large articles.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: June 10, 2003
    Assignee: DSM N.V.
    Inventors: Ted. Brink, Chi Sham, Jacob L. Cohen