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:
Jan. 22, 2013
Filed:
Apr. 16, 2009
Mutsumi Maeda, Tokyo, JP;
Hiroaki Furukawa, Tokyo, JP;
Mutsumi Maeda, Tokyo, JP;
Hiroaki Furukawa, Tokyo, JP;
Asahi Kasei Chemicals Corporation, Tokyo, JP;
Abstract
Disclosed is a method for producing a polyphenylene ether, which comprises a step of preparing a polymerization solution composed of 10-25 parts by mass of a phenolic compound (M) and 75-90 parts by mass of an aromatic solvent (A) with the total of the compound and the solvent being 100 parts by mass, and 0.1-10 parts by mass of a catalyst (C) containing a metal salt; a step of performing an oxidative polymerization of the phenolic compound (M) by passing an oxygen-containing gas through the polymerization solution; a step of stopping the polymerization by mixing an aqueous chelating agent solution into the polymerization solution; a step of subjecting a diphenoquinone compound produced as a by-product to a quinone binding process or removal by reduction; and a step of obtaining a polyphenylene ether by separating the aqueous phase through liquid-liquid separation. In the method for producing a polyphenylene ether, 0.001-0.004 part by weight of an ion catalyst (D) is added into the polymerization solution before the liquid-liquid separation.