Process for the removal of catalyst from polyphenylene ethers
Abstract
Abstract 1. A process for the removal of the catalyst in the production of high molecular weight polyphenylene ethers from monohydric phenols having alkyl substituents in the two ortho-positions and possibly in the meta-position, but not in the para-position, by oxidative coupling with oxygen or an oxygen-containing gas mixture at from 15 to 50 degrees C in the presence of a catalyst complex of a copper salt and an organic amine in the presence of 1 to 20 parts by weight of solvent per part by weight of the monomer phenol ; inactivating the copper-containing catalyst complex at the end of the oxidative coupling reaction by bringing it into contact with a chelate-complex-forming substance on the presence of an aqueous medium ; and separating off the metal chelate complexes which are soluble in the aqueous phase, as well as other water-soluble constituents, wherein water contained in the reaction mixture is removed by a thermal separation method, and the solid constituents precipitating from the reaction mixture are removed from the polymer solution by a conventional method of separating liquid and solid phases.
Inventors
- 👤 Hans H. Dr. Schuster
- 👤 Juergen Dr. Hambrecht
- 👤 Herbert Dr. Naarmann
- 👤 Volker Dr. Muench
Bibliographic Details
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