EP0341473A3

Process for sulphonating aromatic polyether sulphones, and the sulphonated polyether sulphones

Abstract

The sulfonation of aromatic Polyäthersulfonen succeeds in a controllable manner by means of sulfur trioxide in concentrated sulfuric acid as a solvent. By maintaining a sulfur trioxide content of less than 6 percent by weight, based on solvent, and a reaction temperature of less than 30 ° C, side and degradation reactions can be largely suppressed. The products obtained are suitable for the production of membranes.

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Term ended

Projected expiry passed 22 April 2009, 17.4 years ago.

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Citations
DocumentRelationOfficeCategoryCited during
EP0008895A1CitesEuropean Patent Office (EPO)ASearch report
EP0045194A2CitesEuropean Patent Office (EPO)ASearch report
EP0112724A1CitesEuropean Patent Office (EPO)ADSearch report