Crash bag propellant composition and method for generating nitrogen gas

• US 4,929,290 A
• Filed: 11/17/1989
• Issued: 05/29/1990
• Est. Priority Date: 07/25/1988
• Status: Expired due to Term

• Current Assignee: Hercules Incorporated (Ashland Global Holdings, Inc.)
• Original Assignee: Hercules Incorporated (Ashland Global Holdings, Inc.)
• Inventors: Cartwright, Richard V.
• Primary Examiner(s): Lechert, Jr., Stephen J.
• Application Number:
  US07/437,861
• Time in Patent Office: 193 Days
• Field of Search: 149/35, 149/109.2, 280/734, 280/736, 280/741
• US Class Current: 149/35
• CPC Class Codes: C06B 35/00 Compositions containing a metal azide
• CPC Class Codes: C06D 5/06 by reaction of two or more solids

Abstract

A propellant composition and method for limiting the corrosive properties of by-products from initiated crash bag propellant compositions comprising a 1(a) or 2(a) group metal azide salt, an oxidizer in the form of an oxide of a non-toxic transition metal element, and an effective amount of a modifier component of the formula

Me.sub.x (An).sub.o

wherein

Me is a metal cation selected from iron, copper, cobalt, nickel, and molybdenum;

An is an anion group which is chemically compatible with and capable of reacting with the metal of the azide salt to form nitrogen gas and non-toxic by-products less corrosive than the corresponding hydroxide of the azide metal would be; and

x and o are individually defined as a positive number not exceeding about 4, the sum of which does not exceed about 5.

Claims

1. A propellant composition comprising, in combination,

(a) a metal azide salt component of a group 1(a)- or 2(a)-type metal;

and

(b) an oxide of a non-toxic transition metal element sufficient to react with up to about 70% of said metal azide salt component; and

(c) an effective amount of a modifier component represented by the formula

space="preserve" listing-type="equation">Me.sub.x (An).sub.o

wherein

Me is defined as a cation of a non-toxic transition metal element;

An is defined as a member selected from the group consisting of a carbon-containing, a silicon-containing, and a boron-containing anion group chemically compatible with Me and capable of reacting with said metal azide salt component to obtain non-toxic by-products less basic than a metal hydroxide corresponding to said metal azide salt component; and

x and o are individually defined as positive numbers appropriate to indicate the corresponding chemical formula.

2. A propellant composition of claim 1 wherein the metal azide is a salt of an alkali or alkaline earth metal;

and Me is defined as a metal cation selected from the group consisting of iron, copper, cobalt, nickel, and molybdenum.

3. A propellant composition of claim 1, in which Me is defined as copper;

An is defined as a --[(OH)₂ CO₃ ]^-4 group;

x is a positive number of about 2; and

o is a positive number of about 1.

4. A propellant composition of claim 1, in which Me is defined as iron;

An is defined as a --(CO₃)^-2 group;

x is a positive number of about 1; and

o is a positive number of about 1.

5. A propellant composition of claim 2 wherein the metal azide is sodium azide or potassium azide.

6. A propellant composition of claim 1, comprising at least one of a binder and a lubricant.

7. A propellant composition of claim 2, comprising at least one of a binder and a lubricant.

8. A propellant composition of claim 3, comprising at least one of a binder and a lubricant.

9. A propellant composition of claim 4, comprising at least one of a binder and a lubricant.

10. A safety crash bag device comprising, in combination, an inflatable bag of desired shape receivably connected to a gas-generating means charged with an active amount of gas-generating propellant composition as defined in claim 1 in proximity to means for ignition arranged in potential firing attitude with respect to said gas-generating propellant;

and impact detecting means functionally connected to said detonating means for firing of said detonating means upon exposure to an impact of predetermined severity;

wherein an impacting force on said impact detecting means effects a firing sequence through said means for ignition of said gas-generating propellant, essentially producing inert nitrogen gas in said gas-generating means, and passing said gas to said inflatable bag to create a shock-absorbing barrier.

11. A propellant composition of claim 1, in which An is defined as an anion selected from the group consisting of ##STR2##

12. A propellant composition of claim 2, in which An is defined as

13. A method for reducing corrosive properties of by-products generated by initiating the reaction of a crash bag propellant composition comprising a group 1(a)- or 2(a)-type metal azide component and an oxide of a transition metal as an oxidizer component, comprising replacing said oxidizer component, at least in part, with an effective amount of a modifier component of the formula

View Dependent Claims (14, 15, 16)

14. A method of claim 13 in which the metal azide is sodium azide or potassium azide and An is defined as a member selected from the group consisting of ##STR3##

15. A method of claim 13, in which Me is defined as copper;

An is defined as a --[(OH)₂ CO₃ ]^-4 group;

x is a positive number of about 2; and

o is a positive number of about 1.

16. A method of claim 13, in which Me is defined as iron;

An is defined as a --(CO₃)^-2 group;

x is a positive number of about 1; and

o is a positive number of about 1.