Process for the isolation of polycarbonates based on 4,4'-dihydroxydiphenyl sulphones

US4404351A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Peter Kafer · Krefeld, DE
• Leo Morbitzer
• Dieter Neuray · Krefeld, DE
• Wolfgang Cohnen · Leverkusen, DE
• Werner Nouvertne · Krefeld, DE

Key dates

• Filing date: Sep 20, 1982
• Grant date: Sep 13, 1983
• Expiry date: Sep 20, 2002

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/40
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the isolation of polycarbonates containing 18 to 45 mol % of structural units consisting of sulphone-bisphenols, characterized in that the sulphone-bisphenols are subjected to a polycondensation reaction with oligocarbonates containing chloroformic acid ester end groups, the phases are separated, the organic phase is purified and the sulphone-bisphenol polycarbonates are isolated.