Metal complexes for use as gas generants

• US 5,673,935 A
• Filed: 06/07/1995
• Issued: 10/07/1997
• Est. Priority Date: 01/19/1994
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Innovation Systems, Inc. (Northrop Grumman Corporation)
• Original Assignee: Thiokol Corporation (Howmet Aerospace, Inc.)
• Inventors: Doll, Daniel W., Lund, Gary K., Blau, Reed J., Hinshaw, Jerald C.
• Primary Examiner(s): Miller, Edward A.
• Application Number:
  US08/484,142
• Time in Patent Office: 853 Days
• Field of Search: 280/741, 149/37, 149/45, 149/61, 149/75, 149/77, 149/109.4, 149/22
• US Class Current: 280/741
• CPC Class Codes: C06B 29/00 Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate
• CPC Class Codes: C06B 31/00 Compositions containing an inorganic nitrogen-oxygen salt
• CPC Class Codes: C06B 41/00 Compositions containing a nitrated metallo-organic compound
• CPC Class Codes: C06B 43/00 Compositions characterised by explosive or thermic constituents not provided for in groups C06B25/00 - C06B41/00
• CPC Class Codes: C06D 5/06 by reaction of two or more solids

Abstract

Complex generating compositions and methods for their use are provided. Metal complexes are used as gas generating compositions. These complexes are comprised of a cationic metal template, sufficient oxidizing anion to balance the charge of the complex, and a neutral ligand containing hydrogen and nitrogen. Hyradzine complexes are formulated such that when the complex combusts nitrogen gas and water vapor is produced. Specific examples of such complexes include metal nitrite ammine, metal nitrate ammine, and metal perchlorate ammine complexes, as well as hydrazine complexes. Such complexes are adaptable for use in gas generating devices such as automobile air bags.

Claims

1. A solid gas generating composition formulated for generating gas suitable for use in deploying an air bag or balloon from a supplemental safety restraint system, said gas generating composition comprising

at least one complex of

a transition metal or alkaline earth metal cation,

at least one neutral ligand comprising ammonia, and

sufficient oxdizing anion to balance the charts of the complex;

and

at least one primary oxidizer which consists essentially of a metal-containing oxidizer.

3. A composition according to claim 1 or 2, wherein said primary oxidizer consists essentially of at least one of a metal-containing oxidizer salt or metal oxide.

4. A composition according to claim 1 or 2, wherein said oxidizing anion is coordinated with the metal cation.

6. A composition according to claim 1, wherein said complex comprises hexaammine cobalt (III) nitrate.

7. A composition according to claim 1 or 2, wherein said complex is at least one of a metal nitrite ammine, a metal nitrate ammine, or a metal perchlorate ammine.

8. A composition according to claim 7, wherein said complex is a metal nitrate ammine.

9. A composition according to claim 7, wherein said complex is metal nitrite ammine.

10. A composition according to claim 7, wherein said complex is a metal perchlorate ammine.

11. A composition according to claim 1 or 2, wherein said composition is capable of stoichiometrically combusting to a metal or metal oxide, water and nitrogen.

12. A composition according to claim 1 or 2, wherein said metal cation is of a metal selected from the group consisting of cobalt, copper, chromium, iridium, magnesium, manganese, nickel, palladium, platinum, rhodium, ruthenium, and vanadium.

13. A composition according to claim 12, wherein said metal is cobalt, manganese, or magnesium.

14. A composition according to claim 13, wherein said metal is cobalt.

15. A composition according to claim 13, wherein said metal is manganese.

16. A composition according to claim 12, wherein said metal is magnesium.

17. A composition according to claim 7, wherein said metal cation is of a metal selected from the group consisting of copper, chromium, iridium, magnesium, manganese, nickel, palladium, platinum, rhodium, ruthenium, and vanadium.

18. A composition according to claim 17, wherein said metal is cobalt, manganese, or magnesium.

19. A composition according to claim 1 or 2, wherein said composition includes an effective amount of a secondary oxidizing agent.

20. A composition according to claim 19, wherein said complex is at least one of a metal nitrite ammine, a metal nitrate ammine or a metal perchlorate ammine.

21. A composition according to claim 20, wherein said metal cation in said complex is of a metal selected from the group consisting of copper, chromium, iridium, magnesium, manganese, nickel, palladium, platinum, rhodium, ruthenium, and vanadium.

22. A composition according to claim 21, wherein said metal is cobalt.

23. A composition according to claim 19, wherein said metal is cobalt.

24. A composition according to claim 19, wherein said secondary oxidizing agent is selected from the group consisting of nitrates, nitrites, chlorates, perchlorates, and peroxides.

25. A composition according to claim 1 or 2, wherein said composition includes an effective amount of a secondary fuel.

26. A composition according to claim 25, wherein said complex is a metal nitrite ammine, a metal nitrate ammine, a metal perchlorate ammine or a metal hydrazine.

27. A composition according to claim 26, wherein said metal cation in said complex of a metal is selected from the group consisting of copper, chromium, iridium, magnesium, manganese, nickel, palladium, platinum, rhodium, ruthenium, and vanadium.

28. A composition according to claim 27, wherein said metal is cobalt, manganese, or magnesium.

29. A composition according to claim 25, wherein said additional fuel is selected from the group consisting of boron, aluminum, hydrides of boron or aluminum, and silicon.

31. A composition according to claim 1, wherein said complex comprises a member represented by a formula selected from the group consisting of Cu(NH₃)₂ (NO₂)₂, Co(NH₃)₃ (NO₂)₃, Cr(NH₃)₃ (NO₂)₃, Co(NH₃)₆ Co(NO₂)₆, Co(NH₃)₄ (NO₂)₂ Co(NH₃)₂ (NO₂)₄, Co (NH₃)₄ (NO₂)₂ !NO₂, and Co(NH₃)₂ (NO₃)₃.

2. A solid gas generating composition consisting essentially of

a complex of

a transition metal cation or alkaline earth metal cation,

at lease one neutral ligand comprising ammonia, and

sufficient oxidizing anion to balance the charge of the metal complex;

and

at least one primary oxidizer consisting essentially of a metal-containing oxidizer.

5. A composition according to claim 2 or 3, wherein said complex consists essentially of hexaammine cobalt (III) nitrate.

30. A composition according to claim 2, wherein said complex consists essentially of at least one member represented by a formula selected from the group consisting of Cu(NH₃)₂ (NO₂)₂, Co(NH₃)₃ (NO₂)₃, Cr(NH₃)₃ (NO₂) ₃, Co(NH₃)₆ Co(NO₂)₆, Co(NH₃)₄ (NO₂)₂ Co(NH₃)₂ (NO₂)₄, Co (NH₃)₄ (NO₂)₂ !NO₂, and Co(NH₃)₂ (NO₃)₃.

32. A pellet formulated for use in a gas generator, said pellet being obtained by pelleting a gas generating composition which comprises (a) a complex of a transition metal cation or alkaline earth metal cation and at least one neutral ligand comprising ammonia, and sufficient oxidizing anion to balance the charge of the metal complex;

and (b) at least one primary oxidizer which consists essentially of at least one metal-containing oxidizer.

33. A pellet according to claim 32, wherein said complex is at least one member selected from the group consisting of Cu(NH₃)₂ (NO₂)₂, Co(NH₃)₃ (NO₂)₃, Cr(NH₃)₃ (NO₂)₃, Co(NH₃)₆ Co(NO₂)₆, Co(NH₃)₄ (NO₂)₂ Co(NH₃)₂ (NO₂)₄, Co(NH₃)₄ (NO ₂)₂ !NO₂, and Co(NH₃)₂ (NO₃)₃.

34. A pellet according to claim 32, wherein said metal is selected from the group consisting of cobalt, copper, chromium, iridium, magnesium, manganese, nickel, palladium, platinum, rhodium, ruthenium, and vanadium.

35. A pellet according to claim 32, wherein said primary oxidizer consists essentially of at lease one of metal-containing oxidizer salt or metal oxide.

36. A pellet according to claim 32, wherein the metal cation comprises cobalt.

37. A gas generating device containing a solid gas generating composition formulated for generating gas capable of being used to deploy an air bag or balloon from a supplemental safety restraint system, said gas generating composition comprising (a) at least one complex of a transition metal or alkaline earth metal cation, at least one neutral ligand comprising ammonia, and sufficient oxidizing anion to balance the charge of the complex;

and (b) at least one primary oxidizer which consists essentially of a metal-containing oxidizer.

38. An air bag system comprising:

a collapsed, inflatable air bag;

a gas generating device connected to said air bag, said gas-generating device containing a gas-generating composition adapted for use in said gas-generating device, said gas generating composition comprising (a) at least one complex of a transition metal or alkaline earth metal cation, at least one neutral ligand comprising ammonia and sufficient oxidizing anion to balance the charge of the complex; and

(b) at least one primary oxidizer which consists essentially of a metal-containing oxidizer, and means for igniting said gas-generating composition.

39. An air bag system according to claim 38, wherein said complex is at least one metal nitrite ammine, metal nitrate ammine, or metal perchlorate ammine.

40. An air bag system according to claim 38, wherein said primary oxidizer consists essentially of at least one of metal-containing oxidizer salt or metal oxide.

41. An air bag system according to claim 38, wherein said complex is at least one metal nitrite ammine, metal nitrate ammine, or metal perchlorate ammine;

said at least one primary oxidizer consists essentially of at least one of metal-containing oxidizer salt or metal oxide.

42. A vehicle equipped with an air bag system according to claim 38, 39, 40, or 41.