Patents by Inventor Stephan Kohlstruk

Stephan Kohlstruk 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: 9937483
    Abstract: Isophoronediamine, is prepared by A) subjecting isophoronenitrile directly in one stage to aminating hydrogenation to give isophoronediamine in the presence of ammonia, hydrogen, a hydrogenation catalyst and an optional additive, and in the presence or absence of an organic solvent; or B) first converting isophoronenitrile fully or partly in at least two or more than two stages to isophoronenitrile imine, and subjecting the isophoronenitrile imine to aminating hydrogenation to give isophoronediamine as a pure substance or in a mixture with another component and/or isophoronenitrile, in the presence of at least ammonia, hydrogen and a catalyst.
    Type: Grant
    Filed: March 28, 2016
    Date of Patent: April 10, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Stephan Kohlstruk, Anne Rittsteiger, Alexander Martin Ruefer, Norbert Schlueter, Sven Schneider, Sabrina Sowka, Guido Streukens, Stefan Roeder, Monika Berweiler
  • Publication number: 20180093952
    Abstract: The present invention relates to a process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine, which can be used as hardener in epoxide applications.
    Type: Application
    Filed: December 5, 2017
    Publication date: April 5, 2018
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Patent number: 9878979
    Abstract: The present invention relates to the fine purification of isophoronenitrile (IPN) by melt crystallization.
    Type: Grant
    Filed: November 25, 2016
    Date of Patent: January 30, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Joerg-Joachim Nitz, Stephan Kohlstruk, Robert Jansen, Anja Mueller, Jan Cassens, Axel Hengstermann
  • Patent number: 9878500
    Abstract: Provided is a prepreg composed of a fibrous substrate impregnated with a reactive or highly reactive polymer composition as a matrix material. The reactive or highly reactive polymer composition contains a (meth)acrylate-based resin comprising at least one of a hydroxyl group, an amine group, a thiol group, an initiator and/or accelerator, and a di- or polyisocyanate which has been internally capped, capped with a capping agent, or a combination thereof. The (meth)acrylate-based resin contains from 20% by weight to 70% by weight of at least one (meth)acrylate monomer and from 1% by weight to 50% by weight of at least one prepolymer.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: January 30, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Guenter Schmitt, Sandra Reemers, Emmanouil Spyrou, Heike Heeb, Stephan Kohlstruk, Friedrich Georg Schmidt, Elke Gollan
  • Patent number: 9868702
    Abstract: A process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine by A) reacting triacetonamine (TAA) and malononitrile to afford the intermediate 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile, and B) hydrogenating 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar. In another embodiment, the hydrogenation in step B) of the process is performed in two stages at 20-120° C. and at 20-300 bar.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: January 16, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Patent number: 9868699
    Abstract: Cations are removed from a substance stream that is produced during the production of isophoronenitrile with the help of a cation exchanger.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: January 16, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Joerg-Joachim Nitz, Stephan Kohlstruk, Robert Jansen, Andreas Merkel, Anja Mueller, Jan Cassens, Axel Hengstermann
  • Patent number: 9862673
    Abstract: A diamine 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine of formula 1 and a process for producing 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone (IP) and malononitrile to afford the intermediate 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile, and B) hydrogenating 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: January 9, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170362163
    Abstract: Process for preparing isophoronediamine, characterized in that A) isophoronenitrile is subjected directly in one stage to aminating hydrogenation to give isophoronediamine in the presence of ammonia, hydrogen, a hydrogenation catalyst and possibly further additions, and in the presence or absence of organic solvents; or B) isophoronenitrile is first converted fully or partly in at least two or more than two stages to isophoronenitrile imine, and this isophoronenitrile imine is subjected to aminating hydrogenation to give isophoronediamine as a pure substance or in a mixture with other components and/or isophoronenitrile, in the presence of at least ammonia, hydrogen and a catalyst.
    Type: Application
    Filed: January 26, 2016
    Publication date: December 21, 2017
    Applicant: Evonik Degussa GmbH
    Inventors: Stephan Kohlstruk, Anne Rittsteiger, Alexander Martin Rüfer, Norbert Schlüter, Sven Schneider, Sabrina Sowka, Guido Streukens, Stefan Röder, Monika Berweiler
  • Publication number: 20170355810
    Abstract: An epoxy resin composition including A) at least one epoxy compound, and B) a hardener composition including B1) from 0.1%-100% by weight of 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine, and B2) from 99.9%-0% by weight of at least one further diamine and/or polyamine, where the stoichiometric ratio of the epoxy groups of A) and the number of active hydrogen atoms of the functional groups of B) varies from 1:2 to 2:1.
    Type: Application
    Filed: May 24, 2017
    Publication date: December 14, 2017
    Inventors: Eike Langkabel, Martina Ortelt, Dirk Fuchsmann, Jaclyn Balthasar, Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk
  • Publication number: 20170355662
    Abstract: A compound of the structural formula 1 Also disclosed is a process for producing 2-(3-(aminomethyl)-3,5,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone nitrile and malononitrile to afford the intermediate 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile, and B) hydrogenating 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170355809
    Abstract: An epoxy resin composition including A) at least one epoxy compound and B) a hardener composition including B1) 0.1%-100% by weight of 2-(3-(aminomethyl)-3,5,5-trimethylcyclohexyl)propane-1,3-diamine, and B2) 99.9%-0% by weight of at least one further diamine and/or polyamine, where the stoichiometric ratio of the epoxy groups of A) and the number of active hydrogen atoms of the functional groups of B) varies from 1:2 to 2:1.
    Type: Application
    Filed: May 23, 2017
    Publication date: December 14, 2017
    Inventors: Eike Langkabel, Martina Ortelt, Dirk Fuchsmann, Jaclyn Balthasar, Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk
  • Publication number: 20170355674
    Abstract: A process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine by A) reacting triacetonamine (TAA) and malononitrile to afford the intermediate 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile, and B) hydrogenating 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar. In another embodiment, the hydrogenation in step B) of the process is performed in two stages at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170355808
    Abstract: An epoxy resin composition including A) at least one epoxy compound, and B) a hardener composition including B1) from 0.1%-100% by weight of 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine, and B2) from 99.9%-0% by weight of at least one further diamine and/or polyamine, where the stoichiometric ratio of the epoxy groups of A) and the number of active hydrogen atoms of the functional groups of B) varies from 1:2 to 2:1.
    Type: Application
    Filed: May 24, 2017
    Publication date: December 14, 2017
    Inventors: Eike Langkabel, Martina Ortelt, Dirk Fuchsmann, Jaclyn Balthasar, Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk
  • Publication number: 20170355661
    Abstract: A diamine 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine of formula 1 and a process for producing 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone (IP) and malononitrile to afford the intermediate 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile, and B) hydrogenating 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170298003
    Abstract: A process for fine purification of isophoronediamine (IPDA), including producing IPDA by aminating hydrogenation of isophorone nitrile in the presence of at least ammonia, hydrogen, a a hydrogenation catalyst and optionally further additions to obtain a crude IPDA, and subjecting the crude IPDA to a fine purification via two vacuum distillation columns, wherein in the first vacuum distillation column the removal of any remaining relatively low-boiling byproducts is effected and in the second vacuum distillation column the IPDA is obtained in pure form as tops and thus separated from the organic residues, and wherein the first vacuum distillation column has vacuum distillation column has a partial condenser fitted to it.
    Type: Application
    Filed: March 30, 2017
    Publication date: October 19, 2017
    Inventors: Anne Rittsteiger, Alexander Martin Rüfer, Guido Streukens, Stephan Kohlstruk, Matthias Orschel, Matthias Mendorf, Jorn Walscharts, Axel Hengstermann, Anja Müller
  • Publication number: 20170152217
    Abstract: The present invention relates to the fine purification of isophoronenitrile (IPN) by melt crystallization.
    Type: Application
    Filed: November 25, 2016
    Publication date: June 1, 2017
    Applicant: Evonik Degussa GmbH
    Inventors: Joerg-Joachim NITZ, Stephan KOHLSTRUK, Robert JANSEN, Anja MUELLER, Jan CASSENS, Axel HENGSTERMANN
  • Publication number: 20160289164
    Abstract: Isophoronediamine, is prepared by A) subjecting isophoronenitrile directly in one stage to aminating hydrogenation to give isophoronediamine in the presence of ammonia, hydrogen, a hydrogenation catalyst and an optional additive, and in the presence or absence of an organic solvent; or B) first converting isophoronenitrile fully or partly in at least two or more than two stages to isophoronenitrile imine, and subjecting the isophoronenitrile imine to aminating hydrogenation to give isophoronediamine as a pure substance or in a mixture with another component and/or isophoronenitrile, in the presence of at least ammonia, hydrogen and a catalyst.
    Type: Application
    Filed: March 28, 2016
    Publication date: October 6, 2016
    Applicant: Evonik Degussa GmbH
    Inventors: Stephan KOHLSTRUK, Anne RITTSTEIGER, Alexander Martin RUEFER, Norbert SCHLUETER, Sven SCHNEIDER, Sabrina SOWKA, Guido STREUKENS, Stefan ROEDER, Monika BERWEILER
  • Publication number: 20160272580
    Abstract: Cations are removed from a substance stream that is produced during the production of isophoronenitrile with the help of a cation exchanger.
    Type: Application
    Filed: March 21, 2016
    Publication date: September 22, 2016
    Applicant: Evonik Degussa GmbH
    Inventors: Joerg-Joachim NITZ, Stephan KOHLSTRUK, Robert JANSEN, Andreas MERKEL, Anja MUELLER, Jan CASSENS, Axel HENGSTERMANN
  • Patent number: 9433969
    Abstract: A 3D extrusion print process for producing multicolored three-dimensional objects is provided. The process produces mechanically stable, multicolored 3D objects with good color definition. The process according to the invention is based on coating, upstream of the printing head, of the polymer strand used for producing the actual object, and on fixing of the coating upstream of entry of the polymer strand into the printing head. Downstream of the extrusion process in the printing head, the coating remains predominantly at the surface of the extruded strand.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: September 6, 2016
    Assignee: EVONIK RÖHM GmbH
    Inventors: Markus Pridoehl, Guenter Schmitt, Dirk Poppe, Stephan Kohlstruk, Benjamin Hammann, Sonja Cremer, Kris Beks, Ludo Dewaelheyns
  • Patent number: 9283714
    Abstract: The invention relates to a modified fused deposition modeling process for production of multicolored three-dimensional objects. More particularly, the invention relates to a 3D printing process with which 3D objects with particularly good color appearance compared to the prior art can be produced. The process according to the invention is based on coloring of the polymer strand used for production of the actual object in the nozzle, and on using a mixing apparatus which comprises a plurality of injection needles, a static mixer or a dynamic mixer.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: March 15, 2016
    Assignee: Evonik Röhm GmbH
    Inventors: Markus Pridoehl, Guenter Schmitt, Dirk Poppe, Stephan Kohlstruk, Benjamin Hammann, Sonja Cremer, Kris Beks, Ludo Dewaelheyns