Patents by Inventor Egbert Nijhof

Egbert Nijhof 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: 9403928
    Abstract: A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising ethylene and optionally a chain transfer agent system (CTA system) into a first autoclave reactor zone operating at polymerization conditions to produce a first zone reaction product, the CTA system of the first reactor zone having a transfer activity Z1; and B. (1) Transferring at least part of the first zone reaction product to a second reactor zone selected from a second autoclave reactor zone or a tubular reactor zone and operating at polymerization conditions, and, optionally, (2) freshly injecting a second feed into the second reactor zone to produce a second zone reaction product, with the proviso that the second reactor zone contains a CTA system having a transfer activity Z2; and with the proviso that the ratio of Z1/Z2 is less than 1.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: August 2, 2016
    Assignee: Dow Global Technologies LLC
    Inventors: Otto J. Berbee, Cornelis Den Doelder, Egbert Nijhof, Mehmet Demirors, Sjoerd A. De Vries
  • Publication number: 20140303309
    Abstract: A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising ethylene and optionally a chain transfer agent system (CTA system) into a first autoclave reactor zone operating at polymerization conditions to produce a first zone reaction product, the CTA system of the first reactor zone having a transfer activity Z1; and B. (1) Transferring at least part of the first zone reaction product to a second reactor zone selected from a second autoclave reactor zone or a tubular reactor zone and operating at polymerization conditions, and, optionally, (2) freshly injecting a second feed into the second reactor zone to produce a second zone reaction product, with the proviso that the second reactor zone contains a CTA system having a transfer activity Z2; and with the proviso that the ratio of Z1/Z2 is less than 1.
    Type: Application
    Filed: April 28, 2014
    Publication date: October 9, 2014
    Applicant: Dow Global Technologies LLC
    Inventors: Otto J. Berbee, Cornelis Den Doelder, Egbert Nijhof, Mehmet Demirors, Sjoerd A. De Vries
  • Patent number: 8729186
    Abstract: A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising ethylene and optionally a chain transfer agent system (CTA system) into a first autoclave reactor zone operating at polymerization conditions to produce a first zone reaction product, the CTA system of the first reactor zone having a transfer activity Z1; and B. (1) Transferring at least part of the first zone reaction product to a second reactor zone selected from a second autoclave reactor zone or a tubular reactor zone and operating at polymerization conditions, and, optionally, (2) freshly injecting a second feed into the second reactor zone to produce a second zone reaction product, with the proviso that the second reactor zone contains a CTA system having a transfer activity Z2; and with the proviso that the ratio of Z1/Z2 is less than 1.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: May 20, 2014
    Assignee: Dow Global Technologies LLC
    Inventors: Otto J. Berbee, Cornelis Den Doelder, Egbert Nijhof, Mehmet Demirors, Sjoerd A. De Vries
  • Publication number: 20120252990
    Abstract: A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising ethylene and optionally a chain transfer agent system (CTA system) into a first autoclave reactor zone operating at polymerization conditions to produce a first zone reaction product, the CTA system of the first reactor zone having a transfer activity Z1; and B. (1) Transferring at least part of the first zone reaction product to a second reactor zone selected from a second autoclave reactor zone or a tubular reactor zone and operating at polymerization conditions, and, optionally, (2) freshly injecting a second feed into the second reactor zone to produce a second zone reaction product, with the proviso that the second reactor zone contains a CTA system having a transfer activity Z2; and with the proviso that the ratio of Z1/Z2 is less than 1.
    Type: Application
    Filed: December 14, 2010
    Publication date: October 4, 2012
    Inventors: Otto J. Berbee, Cornelis Den Doelder, Egbert Nijhof, Mehmet Demirors, Sjoerd A. De Vries