03954925 is referenced by 9 patents and cites 2 patents.

A method of making semi-permeable asymmetric membranes for desalting water in conformity with the method of reverse osmosis from a cellulose acetate casing mixture to which as modifying component there is added ammonia, preferably in gaseous condition, as swelling substance. Preferably a solution of cellulose acetate in acetone is employed into which the gaseous ammonia is introduced up to the desired concentration at room temperature, e. g. of 22.degree. C. Casting of the film followed by a brief evaporation period prior to gelling the film in cold water is done at room temperature.

Title
Method of making semi-permeable asymmetric membranes for reverse osmosis
Application Number
426903
Publication Number
3954925
Application Date
September 19, 1974
Publication Date
May 4, 1976
Inventor
Karl W Boddeker
Juliusberg
DT
Agent
Walter Becker
Assignee
Gesellschaft fur Kernenergieverwertung in Schiffbau u Schiffahrt mbH
DT
IPC
B29D 27/04
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