Method for producing polylactic acid and corresponding device

US6875839B2 · kind B2 · utility

Assignee

• Inventa-Fischer GmbH & Co. KG · DE

Inventors

• Luder Gerking · Berlin, DE
• Rainer Hagen · Leverkusen, DE
• Klaus Richter · Marl, DE
• Frank Idler · Potsdam, DE
• Winfried Reimann · Potsdam, DE
• Bernd Hanzsch · Geltow, DE

Key dates

• Filing date: Apr 19, 2001
• Grant date: Apr 5, 2005
• Expiry date: Jun 6, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12P7/62
• WIPO field: Biotechnology
• WIPO sector: Chemistry

Abstract

The invention relates to a method for producing polylactic acid, comprising the steps of obtaining lactic acid from starchy agricultural products by fermentation, ultrapurification of the lactic acid by ultrafiltration, nanofiltration and/or electrodialysis, concentration of the lactic acid and production of a prepolymer, cyclizing depolymerization to dilactide, purification of the dilactide, ring-opening polymerization of the dilactide and demonomerization of the polylactide.