Semipermeable membranes of aromatic disulfimide containing polyamides

US4269967A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Klaus Elfert · Krefeld, DE
• Gerhard D. Wolf · Dormagen, DE
• Hans J. Rosenkranz · Krefeld, DE

Key dates

• Filing date: May 30, 1979
• Grant date: May 26, 1981
• Expiry date: May 30, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G69/42
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to membranes which consist of aromatic polyamides containing disulphimide groups and have relative viscosities .eta..sub.rel of .gtoreq.1.4 as measured on a 0.5% N-methylpyrrolidone solution at 20.degree. C., and which may be used for ultrafiltration and inverse osmosis. The membranes of these polyamides according to the invention have a high permeability to water, for example, a throughflow of 1000-5000 1/m.sup.2 d under a pressure of 20 bars, and a high retention capacity for dissolved substances.