Flexible Template-Directed Microporous Partially Pyrolyzed Polymeric Membranes

• US 20070209506A1
• Filed: 02/26/2007
• Published: 09/13/2007
• Est. Priority Date: 03/10/2006
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Lesch, David A., Liu, Chunqing, Wilson, Stephen T.
• Granted Patent: US 8,083,833 B2
• Time in Patent Office: Days
• US Class Current: 95/45
• CPC Class Codes: B01D 2323/08 Specific temperatures applied
• CPC Class Codes: B01D 2323/081 Heating
• CPC Class Codes: B01D 2323/24 Use of template or surface directing agents [SDA]
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 67/003 by selective elimination of components, e.g. by leaching
• CPC Class Codes: B01D 71/64 Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

This invention describes a new concept of flexible template-directed microporous partially pyrolyzed polymeric membranes which have greatly improved performance in separation of gas pairs compared to their precursor polymeric membranes. Organic hosts, such as crown ethers, cyclodextrins (CDs), calixarenes (CXs), and spherands, or polymeric additives, such as poly(ethylene glycol) (PEG) and polyvinylpyrrolidone (PVP) were used as the micropore-forming templates. Micropore-forming template/polymer blend membranes comprising organic micropore-forming templates embedded in a polymer matrix were prepared by dissolving the organic micropore-forming templates in the polymer solution followed by solution-casting and solvent evaporation or solvent exchange. Low-temperature selectively pyrolyzing micropore-forming templates in the micropore-forming template/polymer blend membranes at a nitrogen flow resulted in the formation of flexible microporous partially pyrolyzed polymeric membranes.

Claims

1. A flexible template-directed microporous partially pyrolyzed polymeric membrane comprising organic micropore-forming templates embedded in a polymer matrix.

2. The polymeric membrane of claim 1 wherein said organic micropore-forming templates are selected from the group consisting of crown ethers, cyclodextrins, calixarenes, and spherands, poly(ethylene glycol)s, polyvinylpyrrolidone, poly(acrylic acid), poly(ethylene oxide)s (PEO), dendritic PEO, hyperbranched amine-terminated PEO, poly(propylene oxide)s (PPO), co-block-poly(ethylene oxide)-poly(propylene oxide)s (PEO-PPO), tri-block-poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)s (PPO-PEO-PPO), poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminepropyl ether) (PAPE), linear and star-shaped poly(caprolactone).

3. The polymeric membrane of claim 1 wherein said polymer matrix comprises at least one polymer selected from the group consisting of polymer is selected from the group consisting of polysulfones;

poly(styrenes), styrene-containing copolymers, polycarbonates;

cellulosic polymers, polyamides and polyimides, polyethers;

poly(arylene oxides), poly(esteramide-diisocyanate);

polyurethanes;

polyesters, polysulfides;

polymers from monomers having alpha-olefinic unsaturation, polyvinyls, polyallyls;

poly(benzobenzimidazole);

polyhydrazides;

polyoxadiazoles;

polytriazoles;

poly (benzimidazole);

polycarbodiimides;

polyphosphazines; and

interpolymers, including block interpolymers containing repeating units from the above such as terpolymers of acrylonitrile-vinyl bromide-sodium salt of para-sulfophenylmethallyl ethers; and

grafts and blends containing any of the foregoing and substituted polymers having as substituents halogens such as fluorine, chlorine and bromine;

hydroxyl groups;

lower alkyl groups;

lower alkoxy groups;

monocyclic aryl; and

lower acyl groups.

4. A process for gas separation using the flexible template-directed microporous partially pyrolyzed polymeric membrane of claim 1 comprising contacting a mixture of gases on one side of said flexible template-directed microporous partially pyrolyzed polymeric membrane to cause said at least one gas to permeate the mixed matrix gas separation membrane;

and removing from a side opposite to said one side of the flexible template-directed microporous partially pyrolyzed polymeric membrane a permeate gas composition comprising a portion of said at least one gas which has permeated said mixed matrix gas separation membrane.

5. A method of making a flexible template-directed microporous partially pyrolyzed polymeric membrane comprising combining a polymer and a micropore-forming template and then heating the polymer and micropore-forming template to a low-temperature pyrolysis.

6. The method of claim 5 wherein said polymer and said micropore-forming template are combined by mixing followed by solution-casting of said flexible template-directed microporous partially pyrolyzed polymeric membrane.

7. The method of claim 5 wherein said polymer is thermally stable up to about 450°

C.

8. The method of claim 5 wherein said polymer is selected from the group consisting of polysulfones;

poly(styrenes), styrene-containing copolymers, polycarbonates;

cellulosic polymers, polyamides and polyimides, polyethers;

poly(arylene oxides), poly(esteramide-diisocyanate);

polyurethanes;

polyesters, polysulfides;

polymers from monomers having alpha-olefinic unsaturation, polyvinyls, polyallyls;

poly(benzobenzimidazole);

polyhydrazides;

polyoxadiazoles;

polytriazoles;

poly (benzimidazole);

polycarbodiimides;

polyphosphazines; and

interpolymers, including block interpolymers containing repeating units from the above such as terpolymers of acrylonitrile-vinyl bromide-sodium salt of para-sulfophenylmethallyl ethers; and

grafts and blends containing any of the foregoing and substituted polymers having as substituents halogens such as fluorine, chlorine and bromine;

hydroxyl groups;

lower alkyl groups;

lower alkoxy groups;

monocyclic aryl; and

lower acyl groups.

9. The method of claim 5 wherein said organic micropore-forming templates are selected from the group consisting of crown ethers, cyclodextrins, calixarenes, and spherands, poly(ethylene glycol)s, polyvinylpyrrolidone, poly(acrylic acid), poly(ethylene oxide)s (PEO), dendritic PEO, hyperbranched amine-terminated PEO, poly(propylene oxide)s (PPO), co-block-poly(ethylene oxide)-poly(propylene oxide)s (PEO-PPO), tri-block-poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)s (PPO-PEO-PPO), poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminepropyl ether) (PAPE), linear and star-shaped poly(caprolactone).