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. 30, 1994
Filed:
Jan. 29, 1993
Robert J Kumpf, Pittsburgh, PA (US);
Aaron D Meltzer, Carnegie, PA (US);
Harald Pielartzik, Pittsburgh, PA (US);
Miles Inc., Pittsburgh, PA (US);
Abstract
A two step process for the preparation of an ester group-containing polyether sulfone is disclosed. In the first step a dihalogenodiphenyl sulfone is reacted with excess amount of an aromatic dihydroxy compound and in a second step the reaction product is reacted with a dicarboxylic acid derivative. The excess amount of the aromatic dihydroxy compound is that amount which is sufficient to react with said derivative to form the corresponding ester. The process of the invention is characterized by its economics and good yield and by the high purity of the product. The thus produced polyether sulfone is useful as a thermoplastic resin and as a reactant in the melt blending process for the preparation of block copolymers.