Production and use of high molecular weight aliphatic polycarbonates

US6767986B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Melanie Moethrath · Goldkronach, DE
• Lothar Bunzel · Kempen, DE
• Hans Deml · Krefeld, DE
• Wolfgang Ebert · Krefeld, DE

Key dates

• Filing date: Apr 22, 2003
• Grant date: Jul 27, 2004
• Expiry date: Jun 8, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/305
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the production of high molecular weight aliphatic polycarbonates is disclosed. The process entails a first stage wherein a low molecular weight aliphatic polycarbonate is prepared and a second stage where the low molecular weight aliphatic polycarbonate is condensed with diaryl carbonate in a melt transesterification process to form a high molecular weight aliphatic polycarbonate. The resulting high molecular weight aliphatic polycarbonate is suitable for the production of extrudates, films and molded articles.