Method for the production of polyamides in extruders

US8765902B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Philippe Desbois · Maikammer, DE
• Michael Kopietz · Frankfurt, DE
• Ralf Neuhaus · Drensteinfurt, DE
• Hagen Stawitzki · Karlsruhe, DE
• Hans-Joachim Weis · Speyer, DE
• Jochen Engelmann · Neustadt, DE

Key dates

• Filing date: Jun 11, 2008
• Grant date: Jul 1, 2014
• Expiry date: Aug 6, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G69/30
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

In a process for preparing a polyamide based on dicarboxylic acids and diamines in an extruder, a solid mixture comprising a monomer mixture composed of 50 mol % of dicarboxylic acid mixture composed of from 60 to 88 % by weight of terephthalic acid and from 12 to 40% by weight of isophthalic acid, in which up to 20% by weight of the dicarboxylic acid mixture may also be replaced by other dicarboxylic acids, and 50 mol % of hexamethylenediamine which may be up to 20% by weight replaced by other C2-30-diamines, in a corotatory twin-screw extruder for a residence time of from 10 seconds to 30 minutes, is heated to a temperature in the range from 150 to 400° C. while removing steam and if appropriate diamines through venting orifices.