Patents by Inventor Jan M. Stouffer

Jan M. Stouffer 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: 6069228
    Abstract: Disclosed is a process for the preparation of polyamide polymers via prepolymer formation in a reactor system comprising a reactor, flasher and separator, crystallization of the prepolymer under controlled temperature conditions and the subsequent conversion of these crystallized prepolymers to high molecular weight polymer.
    Type: Grant
    Filed: August 17, 1998
    Date of Patent: May 30, 2000
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Albert Walter Alsop, Elwood Neal Blanchard, Jeffrey D. Cohen, John Maurice Iwasyk, Clara Young Lin, David Neil Marks, Jan M. Stouffer
  • Patent number: 5990265
    Abstract: Disclosed herein is a novel physical form of low molecular weight poly(trimethylene terephthalate). This form may be produced from molten low molecular weight poly(trimethylene terephthalate) material by means of rapid heat transfer from the material. The poly(trimethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: November 23, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Elwood Neal Blanchard, Craig Robert Gochanour, Kenneth Wayne Leffew, Jan M. Stouffer
  • Patent number: 5830982
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight. A higher molecular weight polymer product having a unique physical form can be produced by solid-state polymerization of the low molecular weight poly(ethylene terephthalate).
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: November 3, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5763104
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(trimethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(trimethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(trimethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: June 9, 1998
    Assignee: E. I. du Pont de Nemours & Company
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5744074
    Abstract: This invention relates to a process and apparatus for forming a polyester polymer into particles. More particularly, this invention relates to a process and apparatus for forming crystalline, uniform pellets from an amorphous polyester melt. The polyester pellets have utility, for example, as feedstock for a process for producing higher molecular weight polyesters.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: April 28, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5730913
    Abstract: This invention relates to a process and apparatus for forming a polyester polymer into particles. More particularly, this invention relates to a process and apparatus for forming crystalline, uniform pellets from an amorphous polyester melt. The polyester pellets have utility, for example, as feedstock for a process for producing higher molecular weight polyesters.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: March 24, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5714262
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight. A higher molecular weight polymer product having a unique physical form can be produced by solid-state polymerization of the low molecular weight poly(ethylene terephthalate).
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: February 3, 1998
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5670606
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene 2,6-naphthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene 2,6-naphthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene 2,6-naphthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: September 23, 1997
    Assignee: E. I. Du Pont de Nemours and Compant
    Inventors: Jan M. Stouffer, Elwood Neal Blanchard, Kenneth Wayne Leffew
  • Patent number: 5633018
    Abstract: This invention relates to a process and apparatus for forming a polyester polymer into particles. More particularly, this invention relates to a process and apparatus for forming crystalline, uniform pellets from an amorphous polyester melt. The polyester pellets have utility, for example, as feedstock for a process for producing higher molecular weight polyesters.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: May 27, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood N. Blanchard, Kenneth W. Leffew
  • Patent number: 5540868
    Abstract: The present invention relates to a process for forming robust, uniform, low molecular weight crystalline polyester particles. Such particles are useful for forming higher molecular weight polyesters, for example, by solid-state polymerization. Either conventionally-formed, essentially amorphous, non-molten polyester pellets at ambient temperatures or, alternatively, essentially amorphous molten polyester droplets, can be crystallized by rapidly subjecting the droplets or pellets to a thermal shock according to the process of the present invention.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: July 30, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood N. Blanchard, Kenneth W. Leffew
  • Patent number: 5532333
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene terephtalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: July 2, 1996
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood N. Blanchard, Kenneth W. Leffew
  • Patent number: 5510454
    Abstract: Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene terephtalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: April 23, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Jan M. Stouffer, Elwood N. Blanchard, Kenneth W. Leffew