Purification of polycarbonates

• US 8,252,891 B2
• Filed: 09/17/2009
• Issued: 08/28/2012
• Est. Priority Date: 09/17/2008
• Status: Active Grant

• Current Assignee: Saudi Aramco Technologies Company
• Original Assignee: Novomer, Inc (Danimer Scientific, Inc.)
• Inventors: Cherian, Anna E., Conuel, Jeffrey R., Decker, David E., Allen, Scott D.
• Primary Examiner(s): BOYKIN, TERRESSA M
• Application Number:
  US13/119,408
• Publication Number:
  US 20110201779A1
• Time in Patent Office: 1,076 Days
• Field of Search: 528/405, 528/480
• US Class Current: 528/480
• CPC Class Codes: C08G 64/0208 saturated
• CPC Class Codes: C08G 64/34 and cyclic ethers
• CPC Class Codes: C08G 64/406 Purifying; Drying

Abstract

The present disclosure provides, in part, a method for removing a catalyst from a product of catalyzed aliphatic polycarbonate polymerization reaction.

Claims

1. A method of removing a catalyst from a product of an aliphatic polycarbonate polymerization reaction that was catalyzed by the catalyst, the method comprising contacting the product of the polymerization reaction with a solid phase comprising an ion exchanger, wherein the catalyst comprises a transition metal-ligand complex.

2. A method of claim 1, wherein the ion exchanger comprises an ion exchange resin.

3. The method of claim 2, wherein the ion exchange resin comprises a polymer selected from the group consisting of:

polystyrene, divinylbenzene, polystyrene cross-linked with divinylbenzene, polyvinylpyridine, polymethylmethacrylate, polyolefins, and polytetrafluoroethylene.

4. The method of claim 2, wherein the ion exchange resin comprises polystyrene cross-linked with divinylbenzene.

5. The method of claim 2, wherein the ion exchange resin comprises a cation exchange resin.

6. The method of claim 5, wherein the cation exchange resin comprises an acid.

7. The method of claim 5, wherein the cation exchange resin comprises a sulfonic acid resin.

8. The method of claim 1, wherein the ion exchanger comprises an inorganic solid phase.

9. The method of claim 8, wherein the inorganic solid phase is selected from the group consisting of:

silica, alumina, zirconia, molecular sieves, zeolites, and clays.

10. The method of claim 1, wherein the polymerization reaction further comprises a co-catalyst.

11. The method according to claim 10, wherein the co-catalyst is a Lewis base.

12. The method according to claim 11, wherein the Lewis base is N-methylimidazole (N-MeIm), dimethylaminopyridine (DMAP) or 1,4-diazabicyclo[2.2.2]octane (DABCO).

13. The method according to claim 10, wherein the co-catalyst is a salt.

14. The method according to claim 13, wherein the salt is an ammonium, phosphonium, or arsonium salt.

15. The method according to claim 14, wherein the ammonium salt is tetra-n-butylammonium chloride, tetra-n-butylammonium bromide, tetra-n-butylammonium azide, bis(triphenylphosphine)iminium chloride, bis(triphenylphosphine)iminium bromide or bis(triphenylphosphine)iminium acetate.

16. The method according to claim 14, wherein the phosphonium salt is tetraphenyl phosphonium acetate.

17. The method of claim 1, wherein the metal is a Group 6 transition metal.

18. The method of claim 17, wherein the transition metal is chromium or molybdenum.

19. The method of claim 1, wherein the transition metal is a Group 7 transition metal.

20. The method of claim 19, wherein the transition metal is manganese.

21. The method of claim 1, wherein the transition metal is a Group 9 transition metal.

22. The method of claim 21, wherein the transition metal is cobalt.

23. The method of claim 1, wherein the transition metal is a Group 12 transition metal.

24. The method of claim 23, wherein the transition metal is cadmium.

25. The method of claim 1, wherein the transition metal-ligand complex comprises a salen ligand.

26. The method of claim 25, wherein the salen ligand is selected from the group consisting of:

27. The method of claim 26, wherein the catalytic transition metal complex is selected from the group consisting of:

28. The method of claim 27, wherein the catalytic transition metal complex is selected from the group consisting of:

29. The method of claim 1, wherein the transition metal-ligand complex comprises a porphyrin ligand.

30. The method of claim 1, wherein the transition metal-ligand complex comprises a polymerization initiator.

31. The method of claim 1, wherein the aliphatic polycarbonate is selected from the group consisting of:

poly(propylene carbonate), poly(ethylene carbonate), poly(cyclohexene carbonate), poly(butylene carbonate), poly(cyclopentene carbonate), poly(cyclooctene carbonate), poly(limonene carbonate), and poly(norbornene carbonate).

32. The method of claim 1, wherein the product comprises a solvent.

33. The method of claim 32, wherein the solvent is selected from the group consisting of ethyl acetate, n-propyl acetate, isopropyl acetate, n-butylacetate, acetone, butanone, tetrahydrofuran, and combinations thereof.

34. The method of claim 1, wherein the product is substantially free of epoxides.

35. The method of claim 1, wherein the catalyzed aliphatic polymerization reaction was quenched with an acid before the contacting step.

36. The method of claim 35, wherein the acid contains a non-nucleophilic anion.

37. The method of claim 35, wherein the acid is p-toluene sulfonic acid.

38. The method of claim 1, wherein the solid phase comprises a plurality of beads and the contacting step comprises contacting the product with the plurality of beads.

39. The method of claim 38, wherein the plurality of beads are arranged in a column and the contacting step comprises flowing the product through the column.

40. The method of claim 39, wherein the contacting step comprises recirculating the product through the column.

41. The method of claim 38, wherein the plurality of beads are arranged in a vessel and the contacting step comprises mixing the product with the plurality of beads.

42. The method of claim 1, wherein the solid phase comprises a porous material and the contacting step comprises contacting the product with the porous material.

43. The method of claim 42, wherein the contacting step comprises flowing the product through at least a portion of the porous material.

44. The method of claim 1, wherein the solid phase comprises a polymer selected from the group consisting of polystyrene, divinylbenzene, and combinations thereof.

45. The method of claim 1, wherein the solid phase comprises silica.

46. The method of claim 1, wherein the solid phase comprises a sulfonic acid derivatized polystyrene-divinylbenzene copolymer.

47. The method of claim 1, wherein the solid phase comprises sulfonic acid derivatized silica.

48. The method of claim 1, further comprising a step of contacting the polymer solution with a second solid phase.

49. The method of claim 48, wherein the second solid phase is an acid-absorbing resin.

50. The method of claim 49, wherein the acid-absorbing resin is an anion exchange resin.

51. The method of claim 1, wherein the product comprises an aliphatic polycarbonate selected from the group consisting of:

poly(propylene carbonate);

poly(ethylene carbonate);

poly(butylene carbonate);

poly(cyclohexene carbonate);

poly(3-vinyl cyclohexene carbonate);

poly(limonene carbonate);

poly(norbornene carbonate);

poly(cyclopentene carbonate);

poly(cyclooctene carbonate); and

copolymers of any two or more of these.

52. The method of claim 1, wherein the product comprises poly(propylene carbonate).

53. The method of claim 1, wherein the product comprises poly(ethylene carbonate).

54. The method of claim 1, wherein the product comprises a polymer of propylene oxide, carbon dioxide and one or more epoxides selected from the group consisting of:

ethylene oxide, epichlorohydrin, glycidyl ethers, glycidyl esters, 1,2-butylene oxide, 2,3-butylene oxide, cyclopentene oxide, cyclohexene oxide, 3-vinyl cyclohexene oxide, cyclooctene oxide, norbornene oxide and limonene oxide.

55. The method of claim 1, wherein the product comprises poly(ethylene-co-propylene carbonate).

56. The method of claim 1, wherein the transition metal ligand complex is selected from the group consisting of:

57. The method of claim 56, wherein M is Co(III).

58. A method of purifying a product of an aliphatic polycarbonate polymerization reaction, the method comprising steps of:

1. contacting the product of the polymerization reaction with a first solid phase comprising an acidic ion exchanger; and

2. subsequently contacting the product of the polymerization reaction with a second solid phase comprising a basic ion exchanger.