The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 02, 1986
Filed:
May. 10, 1985
Applicant:
Inventors:
Martin Bartmann, Recklinghausen, DE;
Klaus Burzin, Marl, DE;
Assignee:
Chemische Werke Huls AG, Marl, DE;
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528212 ; 528214 ; 528215 ; 528217 ; 528492 ;
Abstract
The invention relates to a method for producing a polyphenylene ether, in which the oxidative coupling reaction of a di-ortho-substituted phenol is carried out in a solvent comprised of a chlorinated hydrocarbon, an aromatic solvent, or a mixture of one of these solvents with an alcohol or ketone. The reaction is terminated by removing or using up the oxygen-containing reaction gas, adding hydrazine to the reaction mixture, and filtering out the resulting precipitate. The precipitate may be reused along with a suitable amine, to comprise a catalyst for a subsequent oxidative coupling reaction.