Process for the preparation of polymers with diphenol carbonate end groups

US4267303A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Klaus Konig · Leverkusen, DE
• Manfred Schreckenberg · Krefeld, DE
• Christian Lindner · Bensheim, DE
• Carlhans Suling · Odenthal, DE
• Dieter Freitag · Krefeld, DE

Key dates

• Filing date: Aug 27, 1979
• Grant date: May 12, 1981
• Expiry date: Aug 27, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

This disclosure is concerned with a single step process for the production of diphenol terminated polycarbonates by the transesterification of diphenols, bis-aryl carbonates and polymeric diols with aliphatically bound terminal hydroxyl groups. These diols are selected from polyesters, polyethers, polythioethers and polyacetals. The transesterification is carried out at elevated temperatures under vacuum optionally in the presence of a catalyst with the ratios of the reactants being such as to avoid the retention of any terminal aliphatic hydroxyl groups or aryl carbonate groups.