Method for the production of porous bodies with adjustable total pore volume, adjustable pore size and adjustable pore walls

US4594207A · kind A · utility

Assignee

• Akzo N.V. · NL

Inventors

• Christoph Josefiak · Rimbach, DE
• Friedbert Wechs · Bad Mergentheim, DE

Key dates

• Filing date: Feb 10, 1983
• Grant date: Jun 10, 1986
• Expiry date: Feb 10, 2003

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2201/052
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Porous bodies, particularly membranes in the form of hollow filaments, are produced by heating a polymer above the upper critical temperature T.sub.c in a mixture of two compounds A and B, liquid and miscible at the dissolving temperature, whereby the employed mixture (polymer, compounds A and B) in liquid aggregate state displays a miscibility gap, the compound A is a solvent for the polymer and the compound B, which preferably is a non-solvent or a swelling agent for the polymer, raises the phase separation temperature of a solution composed of the polymer and compound A. After the dissociation, the components A and/or B if necessary are extracted. Through use of non-toxic substances such as e.g. edible oil as compound A and castor oil as compound B, bodies are obtained which are non-toxic and unobjectionable for use in medical areas and in the foods industry, among others.