Patents by Inventor Dirk Andrejewski

Dirk Andrejewski 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: 6046286
    Abstract: A process for the radical polymerization of ethylenically unsaturated monomers in an aqueous medium has (a) the starting solution used for the polymerization and the educts required for polymerization such as monomers, germ latex, buffering agents, emulsifiers and/or protective colloids are introduced into a pre-mixing device and thoroughly mixed, heated before being transferred to the polymerization vessel to the polymerization temperature, no initiator being used if a thermal radical initiator is used and only individual initiator components being used where a redox initiator system is used; (b) once the mixture has reached polymerization temperature, it is transferred to a polymerization vessel, the wall of which during the transfer and polymerization is maintained by cooling at a temperature below the polymerization temperature; polymerization is started by adding the thermal initiator or additional initiator components of the redox initiator system, the other educts being added at the start of and/or dur
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: April 4, 2000
    Assignee: Vinnoiit Kunststoff GmbH
    Inventors: Kurt Kreilein, Dirk Andrejewski, Helmut Hammer, Hellmut Jetzlsperger
  • Patent number: 5211877
    Abstract: The present invention relates to liquid-crystalline compounds and to a process for preparing liquid-crystalline polyorganosiloxanes having methacryloxy and/or acryloxy groups by the reaction of organosiloxanes having hydrogen atoms bonded directly to silicon atoms and/or organosilanes which can be condensed to form organosiloxanes having hydrogen atoms bonded directly to silicon atoms, with alkenes and/or alkynes having mesogenic groups, which comprises reacting in a first step the organosiloxanes with an alkene and/or alkyne having at least one non-enolic hydroxyl group protected by a protective group, and in a second step the protective group is removed and the hydroxyl group which is now free is esterified with (meth)acrylic acid, esters, anhydrides and/or halides thereof and thereafter optionally condensing the organosilanes to organosiloxanes.
    Type: Grant
    Filed: August 31, 1989
    Date of Patent: May 18, 1993
    Assignee: Consortium fur elektrochemische Industrie GmbH
    Inventors: Dirk Andrejewski, Magdi Gohary, Hans-Joachim Luckas, Rainer Winkler, Franz-Heinrich Kreuzer