Patents Assigned to Chemische Werk Huls Aktiengesellschaft
  • Process for the production of a polyphenylene ether protected from molecular weight degradation
    Patent number: 4746723
    Abstract: A process for the production of a polyphenylene ether by quenching a transition metal catalyzed oxidative coupling reaction of a di-ortho-substituted phenol, and separation of the metal component. The process comprises:(1) removing the oxygen required for the coupling reaction,(2) contacting the reaction solution with hydrogen sulfide, a solution containing sulfide ions or a mixture thereof, and(3) separating the resulting precipitate.
    Type: Grant
    Filed: May 13, 1985
    Date of Patent: May 24, 1988
    Assignee: Chemische Werk Huls Aktiengesellschaft
    Inventors: Martin Bartmann, Klaus Burzin, Klaus Bevers