Semipermeable thin-film membranes comprising siloxane, alkoxysilyl and aryloxysilyl oligomers and copolymers

• US 4,781,733 A
• Filed: 07/16/1987
• Issued: 11/01/1988
• Est. Priority Date: 07/23/1986
• Status: Expired due to Term

• Current Assignee: Bend Research Inc. (Lonza Group AG)
• Original Assignee: Bend Research Inc. (Lonza Group AG)
• Inventors: Friesen, Dwayne T., Babcock, Walter C.
• Primary Examiner(s): Spitzer, Robert
• Application Number:
  US07/074,247
• Time in Patent Office: 474 Days
• Field of Search: 55/16, 55/68, 55/158, 55/73
• US Class Current: 95/49
• CPC Class Codes: B01D 69/125 In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
• CPC Class Codes: B01D 69/1251 by interfacial polymerisation
• CPC Class Codes: B01D 71/56 Polyamides, e.g. polyester-amides
• CPC Class Codes: B01D 71/70 Polymers having silicon in the main chain, with or without sulfur, nitrogen, oxygen or carbon only
• CPC Class Codes: B01D 71/701 Polydimethylsiloxane
• CPC Class Codes: C08G 77/38 Polysiloxanes modified by chemical after-treatment C08G77/045 takes precedence

Abstract

Novel semiperimeable membranes and thin film composite (TFC) gas separation membranes useful in the separation of oxygen, nitrogen, hydrogen, water vapor, methane, carbon dioxide, hydrogen sulfide, lower hydrocarbons, and other gases are disclosed. The novel semipermeable membranes comprise the polycondensation reaction product of two complementary polyfunctional compounds, each having at least two functional groups that are mutually reactive in a condensation polymerization reaction, and at least one of which is selected from siloxanes, alkoxsilyls and aryloxysilyls. The TFC membrane comprises a microporous polymeric support, the surface of which has the novel semipermeable film formed thereon, preferably by interfacial polymerization.

Claims

1. A semipermeable membrane comprising the polycondensation reaction product of two complementary polyfunctional compounds, at least one of which is selected from a group consisting essentially of siloxanes, alkoxysilanes, and aryloxysilanes, each of said complementary polyfunctional compounds having at least two functional groups selected from a member of Group A or Group B:

space="preserve" listing-type="tabular">______________________________________ Group A Group B ______________________________________ --COX --NHR.sub.h --SO.sub.2 X --OH --NCO --SH --POXR.sub.o --NR.sub.h COX ______________________________________

where X is halide;

R_o is selected from alkyloxy and substituted alkyloxy containing 1 to 18 carbons in the carbon chain, alkyl and substituted alkyl containing from 1 to 18 carbons in the carbon chain,cycloakyl, substituted cycloalkyl, and substituted heterocycloalkyl, aryl and substituted aryl;

R_h is selected from hydrogen and R_o ;

provided that when said at least two functional groups are selected from group A for one of said complementary polyfunctional compounds, said at least two functional groups are selected from group B for the other of said complementary polyfunctional compounds, and vice-versa; and

further provided that when at least one of said complementary polyfunctional compounds is a siloxane and the functional group from group A is --NCO, the functional group from group B is not --NHR_h.

2. The membrane of claim 1 wherein the polycondensation is by interfacial polymerization.

3. The membrane of claim 1 wherein the Group A at least two functional groups are --COX and the Group B at least two functional groups are --NHR_h.

4. The membrane of claim 1 wherein the Group A at least two functional groups are --COX and the Group B at least two functional groups are --OH.

5. The membrane of claim 1 wherein the Group A at least two functional groups are --NCO and the Group B at least two functional groups are --OH.

6. The membrane of claim 1 wherein at least one of said complementary polyfunctional compounds is a siloxane of the structure ##STR6## where F'"'"' is selected from members of Group A and Group B R is lower alkyl, halogen-substituted lower alkyl, and aryl;

R'"'"' and R" are hydrogen or lower alkyl; and

m and n are zero or integers up to 500.

7. The membrane of claim 6 wherein F'"'"' on one of said complementary polyfunctional compounds is an amine;

F'"'"' on the other of said complementary polyfunctional compounds is --COX;

m is 2 and n averages from 5 to 75.

8. The membrane of claim 7 wherein F'"'"' on the other of said complementary polyfunctional compounds is --OH.

9. The membrane of claim 1 wherein at least one of said complementary polyfunctional compounds is an alkoxysilyl or aryloxysilyl of the structure

10. The membrane of claim 1 wherein at least one of said complementary polyfunctional compounds is an alkoxysilyl or aryloxysilyl of the structure ##STR9## where R is aryl or alkyl containing up to 10 carbon atoms;

g and h are numbers selected from 0 and integers from 1 to 12; and

j is an integer from 1 to 20.

11. A thin-film composite separation membrane comprising a microporous polymeric support having a thin polymeric semipermeable film formed on the surface of said support, said film comprising the polycondensation reaction product of two complementary polyfunctional compounds, at least one of which is selected from a group consisting essentially of siloxanes, alkoxysilanes, and aryloxysilanes, each of said complelemtary polyfunctional compounds having at least two functional groups selected from a member of Group A or Group B:

space="preserve" listing-type="tabular">______________________________________ Group A Group B ______________________________________ --COX --NHR.sub.h --SO.sub.2 X --OH --NCO --SH --POXR.sub.o --NR.sub.h COX ______________________________________

where X is halide;

R_o is selected from alkyloxy and substituted alkyloxy containing 1 to 18 carbons in the carbon chain, alkyl and substituted alkyl containing from 1 to 18 carbons in the carbon chain, cycloakyl, substituted cycloalkyl, and substituted heterocycloalkyl, aryl and substituted aryl;

R_h is selected from hydrogen and R_o ;

provided that when said at least two functional groups are selected from group A for one of said complementary polyfunctional compounds, said at least two functional groups are selected from group B for the other of said complementary polyfunctional compounds, and vice-versa; and

further provided that when at least one of said complementary polyfunctional compounds is a siloxane and the functional group from group A is --NCO, the functional group from group B is not --NHR_h.

12. The thin-film composite membrane of claim 11 wherein the polycondensation is by interfacial polymerization.

13. The thin-film composite membrane of claim 11 wherein the Group A at least two functional groups are --COX and the Group B at least two functional groups are --NHR_h.

14. The thin-film composite membrane of claim 11 wherein the Group A at least two functional groups are --COX and the Group B at least two functional groups are --OH.

15. The thin-film composite membrane of claim 11 wherein the Group A at least two functional groups are --NCO and the Group B at least two functional groups are --OH.

16. The thin-film composite membrane of claim 11 wherein said support is selected from the group consisting essentially of polyethylene, polypropylene, polytetrafluoroethylene, cellulose acetate, cellulose triacetate, cellulose butyrate, regenerated cellulose, polysulfone, polyethersulfone, polyamide, polyetheramide, and polyvinylidene fluoride, one of said complementary polyfunctional compounds is of the formula

17. The thin-film composite membrane of claim 16 wherein F is an amine, F'"'"' is selected from --COX and --NCO, m is 2 and n averages from 5 to 75.

18. The thin-film composite membrane of claim 17 wherein F is --OH.

19. The thin-film composite membrane of claim 11 wherein the support is selected from sheets and hollow fibers.

20. The thin-film composite separation membrane of claim 11 wherein at least one of said complementary polyfunctional compounds is an alkoxysilyl or aryloxysilyl of the structure

21. The thin-film composite separation membrane of claim 11 wherein at least one of said complementary polyfunctional compounds is an alkoxy-silyl or aryloxy-silyl of the structure ##STR13## where R is aryl or alkyl containing up to 10 carbon atoms;

g and h are numbers selected from 0 and integers from 1 to 12; and

j is an integer from 1 to 20.

22. A method for the separation of oxygen and nitrogen comprising splitting a feed stream containing oxygen and nitrogen with the thin-film composite separation membrane of claims 11, 15, 20, or 21 into an oxygen-rich permeate stream and a nitrogen-rich residue

23. A method for the separation of hydrogen and nitrogen comprising splitting a feed stream containing hydrogen and nitrogen with the thin-film composite separation membrane of claims 11, 15, 20 or 21 into an hydrogen-rich permeate stream and a nitrogen-rich residue stream.

24. A method for the separation of carbon dioxide and a hydrocarbon mixture comprising alkanes and alkenes containing one to four carbon atoms, the method comprising splitting a feed gas stream containing carbon dioxide and said hydrocarbon mixture with the thin-film composite separation membrane of claims 11, 15, 20 or 21 into a carbon dioxide-rich permeate stream and a hydrocarbon mixture-rich residue stream.

25. The method of claim 24 wherein said hydrocarbon mixture is predominantly methane.

26. A method for the separation of hydrogen and a hydrocarbon mixture comprising alkanes and alkenes containing one to four carbon atoms, the method comprising splitting a feed stream containing hydrogen and said hydrocarbon mixture with the thin-film composite separation membrane of claims 11, 15, 20 or 21 into a hydrogen-rich permeate stream and a hydrocarbon mixture-rich residue stream.

27. The method of claim 26 wherein said hydrocarbon mixture is predominantly methane.

28. A method for the separation of hydrogen sulfide and a hydrocarbon mixture comprising alkanes and alkenes containing one to four carbon atoms, the method comprising splitting a feed stream containing hydrogen sulfide and said hydrocarbon mixture with the thin-film composite separation membrane of claims 11, 15, 20 or 21 into a hydrogen sulfide-rich permeate stream and a hydrocarbon mixture-rich residue stream.

29. The method of claim 28 wherein said hydrocarbon mixture is predominantly methane.

30. A method for the separation of water vapor and a gas comprising splitting a gaseous feed stream containing water vapor with the thin-film composite separation membrane of claims 11, 15, 20 or 21 into a water vapor-rich permeate stream and a water vapor-poor residue stream.

31. The method of claim 30 wherein said gaseous feed stream comprises air.

32. The method of claim 30 wherein said gaseous feed stream comprises methane.