Process for separating volatile components from polymers

US7144981B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Thomas König · Nuremberg, DE
• Klemens Kohlgrüber · Lingen (Ems), DE
• Ulrich Liesenfelder · Bensberg, DE
• Michael Bierdel · Leverkusen, DE
• Helmut Meyer · Hilden, DE
• Richard Weider · Leverkusen, DE
• Jorg Kruger · Krefeld, DE

Key dates

• Filing date: Oct 14, 2003
• Grant date: Dec 5, 2006
• Expiry date: Oct 14, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F6/003
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for concentrating polymers by evaporation is disclosed. The process entails (i) obtaining a mixture containing a polymer and volatile component, the volatile components being present in the mixture at an amount less than 20 wt. % relative to the weight of the mixture, and (ii) introducing the mixture in a downward direction under pressure through a plurality of nozzles arranged vertically and next to one another into a degassing container to form an extrudate. The volatile component contains at least one of residual monomers, oligomers and solvents, and the throughput of the mixture per nozzle is 0.3 to 2 kg/h. The vapor pressure of the volatile component of the extrudate is more than 2.5 bar, and the absolute pressure in the degassing container is 50 to 5000 Pa. The polymer prepared by the process is characterized in that it contains volatile components in an amount of less than 300 ppm.