Patents by Inventor Jan A. J. Hendrix

Jan A. J. Hendrix 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: 6495682
    Abstract: The present invention relates to a process for purifying an impure stream of caprolactam while recovering not only pure caprolactam but also medium-to-high pressure steam. Preferably, the stream of impure or crude caprolactam, which comprises at a minimum a substantial portion of water, is obtained from depolymerization of a polyamide-containing composition. The resulting purified caprolactam will have a purity greater than 90 weight percent and the recovered steam will have a temperature sufficiently high to provide a driving force for use with other equipment, for instance, heat exchange equipment.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: December 17, 2002
    Assignee: DSM N.V.
    Inventors: Peter W. H. Cheng, Jan A. J. Hendrix, Leonardus J. G. Raets
  • Patent number: 5668277
    Abstract: One or more polyamides can be depolymerized in the presence of at least one nitrogen-containing compound. The depolymerization takes place at a pressure between about 0.5 and about 5 atm. The polyamide may be in the form of carpet waste or other heterogeneous form. Advantages include better selectivity towards the polyamide monomeric components and use of low pressure equipment to effect depolymerization.
    Type: Grant
    Filed: April 15, 1996
    Date of Patent: September 16, 1997
    Assignee: DSM N.V.
    Inventors: Jan A. J. Hendrix, Martin Booij, Yvonne H. Frentzen
  • Patent number: 5626912
    Abstract: The present invention relates to a tufted fabric and a method of manufacturing the same. The tufted fabric generally comprises a primary backing and tufts mounted in the primary backing to form a fabric with a faceside having piles and a backside having loops. A thermoplastic polymer adhesive, which bonds the tufts to the primary backing, is formed by applying a reactive mixture comprising a polymerizable monomer to the backside of the tufted fabric and in-situ polymerizing the monomers to form the thermoplastic polymer adhesive. The process is particularly advantageous for the manufacture of recyclable tufted fabrics in which the adhesive polymer and tufts are formed from substantially the same polymer. The tufted fabric can be used in articles, such as, for example carpets, rugs and upholstery.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: May 6, 1997
    Assignees: DSM N.V., AlliedSignal Inc.
    Inventors: Jan A. J. Hendrix, Arnoldus M. Kerssemakers, Yousef Mohajer, Forrest E. Sloan
  • Patent number: 5556890
    Abstract: The present invention is for a method of preparing purified .epsilon.-caprolactam from carpet waste containing nylon-6. Contaminated .epsilon.-caprolactam is obtained by depolymerizing nylon-6 from carpet waste. A mixture of the contaminated .epsilon.-caprolactam and water is then hydrogenated in the presence of hydrogen and a hydrogenation catalyst in order to produce purified .epsilon.-caprolactam. The amount of contaminated .epsilon.-caprolactam in the mixture can be between 10 and 95% by weight.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: September 17, 1996
    Assignee: DSM N.V.
    Inventors: Antoon H. T. Halderit, Martin Booij, Jan A. J. Hendrix, Yvonne H. Frentzen