Polymeric membranes for separation of gases

1. A membrane comprising:

a gas permeable support layer; and

a selective polymer layer disposed on the gas permeable support layer, wherein the selective polymer layer comprises an amine-containing polymer and an amino acid salt dispersed within the amine-containing polymer;

wherein the amine-containing polymer comprises a monomer having the structure below:

wherein

R 1 and R 2 are, independently for each occurrence, hydrogen, alkyl, alkenyl, alkynyl, aryl, or cycloalkyl, or R 1 and R 2 , together with the nitrogen atom to which they are attached, form a heterocyclic ring, with the proviso that at least one of R 1 and R 2 is not hydrogen.

2. The membrane of claim 1 , wherein the gas permeable support layer comprises a gas permeable polymer selected from the group consisting of polyamides, polyimides, polypyrrolones, polyesters, sulfone-based polymers, polymeric organosilicones, fluorinated polymers, polyolefins, copolymers thereof, and blends thereof.

3. The membrane of claim 2 , wherein the gas permeable polymer comprises polyethersulfone.

4. The membrane of claim 1 , wherein the gas permeable support layer comprises a gas permeable polymer disposed on a base.

5. The membrane of claim 1 , wherein the membrane further comprises:

an inorganic layer disposed on the gas permeable support layer.

6. The membrane of claim 5 , wherein the inorganic layer comprises a plurality of discreet nanoparticles having an average particle size of less than 1 micron.

7. The membrane of claim 6 , wherein the nanoparticles comprise silicate nanoparticles, alumino-silicate nanoparticles, or a combination thereof.

8. The membrane of claim 7 , wherein the nanoparticles comprise zeolite Y nanoparticles.

9. The membrane of claim 6 , wherein the average particle size of the nanoparticles is from 1 nm to 500 nm.

10. The membrane of claim 1 , wherein the membrane exhibits a CO 2 :N 2 selectivity of from 45 to 350 at 57° C. and 1 atm feed pressure.

11. The membrane of claim 1 , wherein the membrane exhibits a CO 2 permeance of from 100 to 2000 GPU at 57° C. and 1 atm feed pressure.

12. The membrane of claim 1 , wherein the amine-containing polymer comprises a sterically hindered derivative of polyvinylamine.

13. The membrane of claim 12 , wherein the sterically hindered derivative of polyvinylamine comprises a polymer having the structure below

wherein

R 1 and R 2 are, independently for each occurrence, hydrogen, alkyl, alkenyl, alkynyl, aryl, or cycloalkyl, or R 1 and R 2 , together with the nitrogen atom to which they are attached, form a heterocyclic ring, with the proviso that at least one of R 1 and R 2 is not hydrogen; and

n is an integer from 10 to 25,000.

14. The membrane of claim 12 , wherein the sterically hindered derivative of polyvinylamine comprises a random copolymer or block copolymer having the structure below

wherein

R 1 and R 2 are, independently for each occurrence, hydrogen, alkyl, alkenyl, alkynyl, aryl, or cycloalkyl, or Ri and R 2 , together with the nitrogen atom to which they are attached, form a heterocyclic ring, with the proviso that at least one of R 1 and R 2 is not hydrogen;

m is an integer from 10 to 10,000; and

n is an integer from 10 to 10,000.

15. The membrane of claim 1 , wherein the amino acid salt comprises a salt of a compound defined by the formula below

wherein, independently for each occurrence in the amino acid, each of R 1 , R 2 , R 3 and R 4 is selected from one of the following

wherein at least one of R 1 -R 4 comprises an amino group,

or R 1 and R 3 , together with the atoms to which they are attached, form a five-membered heterocycle defined by the structure below when n is 1, or a six-membered heterocycle defined by the structure below when n is 2

16. The membrane of claim 1 , wherein the amino acid salt comprises a glycinate salt or an aminoisobutyrate salt.

17. A method for separating a gaseous mixture comprising a first gas and a second gas, the method comprising contacting a membrane defined by claim 1 with the gaseous mixture under conditions effective to afford transmembrane permeation of the first gas.

18. A method of making a membrane comprising, coating an inorganic layer with a selective polymer, wherein the selective polymer comprises an amine-containing polymer and an amino acid salt dispersed within the amine-containing polymer;

wherein the amine-containing polymer comprises a monomer having the structure below:

wherein

R 1 and R 2 are, independently for each occurrence, hydrogen, alkyl, alkenyl, alkynyl, aryl, or cycloalkyl, or R 1 and R 2 , together with the nitrogen atom to which they are attached, form a heterocyclic ring, with the proviso that at least one of R 1 and R 2 is not hydrogen.

19. A method of making a membrane comprising,

depositing a nanoparticle dispersion on a gas permeable support layer to form an inorganic layer disposed on the gas permeable support layer; and

coating the inorganic layer with a selective polymer, wherein the selective polymer comprises an amine-containing polymer and an amino acid salt dispersed within the amine-containing polymer;

wherein the amine-containing polymer comprises a monomer having the structure below:

wherein

R 1 and R 2 are, independently for each occurrence, hydrogen, alkyl, alkenyl, alkynyl, aryl, or cycloalkyl, or R 1 and R 2 , together with the nitrogen atom to which they are attached, form a heterocyclic ring, with the proviso that at least one of R 1 and R 2 is not hydrogen.