Back to results
US 4,259,183 AGranted
Reverse osmosis membrane
AssigneeMidwest Research Institute
InventorJohn E. Cadotte
Life of this patent
Estimating the term…
Abstract
A composite permselective membrane is prepared by reaction of a film or layer containing cycloaliphatic polyfunctional secondary amines with a triacyl halide or its mixture with a diacyl halide. The membrane is useful in separating components of fluid mixtures or solutions, such as the removal of salts from aqueous solutions by reverse osmosis.
Claims17
A process for preparation of a composite reverse osmosis membrane comprising the steps of:
- (a) coating a porous support with a layer comprising an aqueous solution containing, dissolved therein, an essentially monomeric, polyfunctional, essentially water-soluble secondary amine;
- (b) contacting the said layer with an relatively water-insoluble, essentially monomeric, volatilizable polyfunctional acid halide component having an average acid halide functionality greater than 2.05, for a time sufficient to effect in-situ chain extension and crosslinking reactions between the secondary amine and the polyfunctional acid halide;
- and
- (c) drying the product of step (b) to form the composite reverse osmosis membrane.
1 more element
A process for preparation of a composite reverse osmosis membrane comprising the steps of:
- (a) coating a porous support with a layer of an aqueous medium containing, dissolved therein, an essentially water-soluble polyamide prepolymer terminated with secondary amine functional groups, the secondary amine functionality of said prepolymer being greater than 2.0;
- (b) contacting the said layer with a polyfunctional acid halide for a time sufficient to effect in-situ chain extension and crosslinking reactions between the polyamide prepolymer and the polyfunctional acid halide;
- and
- (c) drying the product of step (b) to form the composite reverse osmosis membrane.
1 more element
Dependencies are inferred from the claim text.