Process for preparing aromatic polyamides of high hydrolysis resistance with controlled water content of diamine

US5149759A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Georg-Emrich Miess · Königstein, DE
• Peter Klein · Burns Lake, CA
• Wilfried Pressler · Kelkheim, DE

Key dates

• Filing date: Apr 3, 1991
• Grant date: Sep 22, 1992
• Expiry date: Apr 3, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G69/32
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

There is described a process for preparing aromatic polyamides of high hydrolysis resistance by reacting aromatic diamines in a conventional organic solvent and in the presence or absence of inorganic salts wherein the diamine, which has a water content of up to 25% by weight, is dissolved in the organic solvent, which may likewise contain water, and the solution is subjected to a vacuum distillation until the water content of the bottom product is <100 ppm and subsequently the inorganic salts if necessary and then the dicarbonyl dichloride are added in a conventional manner and the condensation reaction is performed and concluded in a conventional manner.