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:
Aug. 28, 2018
Filed:
Mar. 22, 2017
Asahi Kasei Kabushiki Kaisha, Chiyoda-ku, Tokyo, JP;
Shigeru Yamamoto, Tokyo, JP;
Akira Mitsui, Tokyo, JP;
ASAHI KASEI KABUSHIKI KAISHA, Chiyoda-ku, Tokyo, JP;
Abstract
Provided is a method for producing polyphenylene ether (PPE) having excellent mechanical properties, heat aging resistance, and color, and in which the content of impurities such as low molecular weight components and catalyst metal is low. The method for producing PPE includes: performing oxidative polymerization of a phenolic compound in a polymerization solution containing the phenolic compound, a catalyst, and an aromatic solvent to obtain a PPE mixed liquid; precipitating PPE to obtain a slurry containing particulate PPE through addition of a polar solvent to the PPE mixed liquid; solid-liquid separating the slurry to obtain wet PPE particles; washing the wet PPE particles to obtain PPE particles through at least one cycle of a washing and solid-liquid separation process in which washing is performed with a washing liquid containing an aromatic solvent and a polar solvent, and in which solid-liquid separation is performed; and drying the PPE particles.