Richard L Grabowsky

US Patent:

42437016, Jan 6, 1981

Filed:

Nov 8, 1979

Appl. No.:

6/092382

Inventors:

Robert L. Riley - La Jolla CA
Richard L. Grabowsky - Bakersfield CA

Assignee:

UOP Inc. - Des Plaines IL

International Classification:

B05D 500

US Classification:

427244

Abstract:

Membranes, which may be used for the separation of gases, comprise a thin film of a semi-permeable material composited on a porous support member. The membranes are prepared by passing a support member through a solution of a halogenated hydrocarbon solvent containing a semi-permeable membrane forming prepolymer and cross-linking agent. This step is then followed by the cross-linking of the prepolymer by treatment at an elevated temperature. The process may be exemplified by passing one finely porous surface of a cellulose nitrate-cellulose acetate support member through a solution of dimethyl silicone in a halogenated solvent such as trifluorotrichloroethane followed by treatment at a temperature in the range of from about 50. degree. to about 150. degree. C. to form the desired membrane.