Composite polyamide membrane
View Patent ↗A method for making a composite polyamide membrane comprising the steps of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of a C 2 -C 20 aliphatic monomer comprising at least one carboxylic acid functional group or salt thereof, and a single amine-reactive functional group; and ii) applying a C 2 -C 20 aliphatic monomer comprising at least one carboxylic acid functional group or salt thereof, and a single amine-reactive functional group to the thin film polyamide layer. Many additional embodiments are described including applications for such membranes.
1. A method for making a composite polyamide membrane comprising a porous support and a thin film polyamide layer, wherein the method comprises the step of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is characterized by including at least one of the following steps:
i) conducting the interfacial polymerization in the presence of a C 2 -C 20 aliphatic monomer that comprises at least one carboxylic acid functional group or salt thereof and a single amine-reactive functional group selected from: acyl halide, anhydride, isocyanate and epoxy; and
ii) applying a C 2 -C 20 aliphatic monomer that comprises at least one carboxylic acid functional group or salt thereof and a single amine-reactive functional group selected from: acyl halide, anhydride, isocyanate and epoxy, to the thin film polyamide layer.
2. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) comprises a single carboxylic acid functional group.
3. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) is an alicyclic compound.
4. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) is selected from is an acyclic compound.
5. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) is represented by Formula (III):
Formula (III):
wherein X is a halogen and n is an integer from 1 to 10.
6. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) is selected from: 4-(chlorocarbonyl)butanoic acid; 5-(chlorocarbonyl)pentanoic acid; 6-(chlorocarbonyl)hexanoic acid; 7-(chlorocarbonyl)heptanoic acid; 8-(chlorocarbonyl)octanoic acid; 9-(chlorocarbonyl)nonanoic acid and 10-(chlorocarbonyl)decanoic acid.
7. The method of claim 1 wherein the aliphatic monomer of steps i) and ii) is represented by at least one of Formulae (IV and V):
wherein X is a halogen.
8. The method of claim 1 wherein the step of applying the polyfunctional monomers to the surface of the porous support comprises applying a polar solution comprising the polyfunctional amine monomer and a non-polar solution comprising the polyfunctional acyl halide monomer; and wherein the non-polar solution further comprises the aliphatic monomer.
9. The method of claim 1 comprising the step of applying a solution comprising the aliphatic monomer to the thin film polyamide layer.