Semipermeable membrane made from a homogeneously miscible polymer blend

US5152894A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Michael Haubs · Bad Kreuznach, DE
• Willi Kreuder · Mainz, DE
• Claus-Peter Krieg · Frankfurt am Main, DE
• Juergen Wildhardt · Haigerloch, DE

Key dates

• Filing date: Jul 22, 1991
• Grant date: Oct 6, 1992
• Expiry date: Jul 22, 2011

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D71/56
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A semipermeable membrane is described which comprises a homogeneously miscible polymer blend of an aromatic polyamide and polyvinylpyrrolidone. The aromatic polyamide is in particular formed of recurrent units of the formula I: ##STR1## wherein E.sup.1 and E.sup.2 are identical or different and are selected from the groupings ##STR2## --AR.sup.1 --, and --AR.sup.1 --X--AR.sup.2, where AR.sup.1 and Ar.sup.2 are the same or different 1,2-phenylene, 1,3-phenylene or 1,4-phenylene groups which may be substituted by (C.sub.1 -C.sub.6)-alkyl, (C.sub.1 -C.sub.6)-alkoxy, --CF.sub.3 or halogen and X denotes PA0 a) a direct bond or one of the following divalent groups: --O--, --C(CF.sub.3).sub.2 --, --SO.sub.2 --, --C(R.sup.1).sub.2 --, with R.sup.1 being hydrogen, (C.sub.1 -C.sub.6)-alkyl or fluoroalkyl having from 1 to 4 carbon atoms in the alkyl group or PA0 --Z--AR.sup.1 --Z--, where Z is one of the groups --O-- and --C(CH.sub.3).sub.2 or PA0 --O--Ar.sup.1 --Y--Ar.sup.2 --O--, where Y has the meaning given under Xa) above. The membrane has pronouned hydrophilic properties and is moreover stable to hydrolyzing agents and oxidants and to the action of heat. It is also resistant to organic …