Smokeless gas generant compositions

• US 6,074,502 A
• Filed: 02/16/1999
• Issued: 06/13/2000
• Est. Priority Date: 11/08/1996
• Status: Expired due to Term

• Current Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Burns, Sean P., Khandhadia, Paresh S.
• Primary Examiner(s): Jordan, Charles T.
• Assistant Examiner(s): Sanchez, Glenda L.
• Application Number:
  US09/250,944
• Time in Patent Office: 483 Days
• Field of Search: 149/36, 149/46
• US Class Current: 149/36
• CPC Class Codes: C06D 5/06 by reaction of two or more solids

Abstract

Thermally stable gas generant compositions incorporate a combination of one or more primary nonazide high-nitrogen fuels selected from a group including tetrazoles, bitetrazoles, and triazoles, and salts thereof; and one or more secondary nonazide high nitrogen fuels selected from azodicarbonamide and hydrazodicarbonamide. The primary and secondary fuels are combined with phase-stabilized ammonium nitrate that when combusted, results in a greater yield of gaseous products per mass unit of gas generant, a reduced yield of solid combustion products, lower combustion temperatures, and acceptable burn rates, thermal stability, and ballistic properties. These compositions are especially suitable for inflating air bags in passenger-restraint devices.

Claims

1. A gas generant composition useful for inflating an automotive air bag passive restraint system comprising a mixture of:

a high-nitrogen nonazide fuel selected from the class consisting of 1-, 3-, and 5-substituted amine salts of triazoles, and, 1- and 5-substituted amine salts of tetrazoles;

a second fuel selected from the group consisting of hydrazodicarbonamide and azodicarbonamide; and

phase stabilized ammonium nitrate.

2. A gas generant composition as claimed in claim 1 wherein said high-nitrogen nonazide fuel is employed in a concentration of 5 to 45% by weight of the gas generant composition, said second fuel is employed in a concentration of 1 to 35% by weight of the gas generant, and, said phase stabilized ammonium nitrate is employed in a concentration of 55 to 85% by weight of the gas generant composition.

3. A gas generant composition as claimed in claim 2 further comprising an inert combination slag former, binder, processing aid, and coolant selected from the group comprising clay, diatomaceous earth, alumina, and silica wherein said slag former is employed in a concentration of 0.1 to 10% by weight of the gas generant composition.

4. A gas generant composition useful for inflating an automotive air bag passive restraint system comprising a mixture of:

a high-nitrogen nonazide fuel selected from the class consisting of 1-, 3-, 5-substituted amine salts of triazoles and 1- and 5-substituted amine salts of tetrazoles, said fuel employed in a concentration of 5 to 45% by weight of the gas generant composition;

a second fuel selected from the group consisting of hydrazodicarbonamide and azodicarbonamide, said second fuel employed in a concentration of 1 to 35% by weight of the gas generant composition; and

an oxidizer consisting of phase stabilized ammonium nitrate, said oxidizer employed in a concentration of 55 to 85% by weight of the gas generant composition,

wherein said fuel is selected from the group consisting of monoguanidinium salt of 5,5'"'"'-Bis-1H-tetrazole, diguanidinium salt of 5,5'"'"'-Bis-1H-tetrazole, monoaminoguanidinium salt of 5,5'"'"'-Bis-1H-tetrazole, diaminoguanidinium salt of 5,5'"'"'-Bis-1H-tetrazole , monohydrazinium salt of 5,5'"'"'-Bis-1H-tetrazole, dihydrazinium salt of 5,5'"'"'-Bis-1H-tetrazole, monoammonium salt of 5,5'"'"'-bis-1H-tetrazole, diammonium salt of 5,5'"'"'-bis-1H-tetrazole, mono-3-amino-1 ,2,4-triazolium salt of 5,5'"'"'-bis-1H-tetrazole, di-3-amino-1,2,4-triazolium salt of 5,5'"'"'-bis-1H-tetrazole, diguanidinium salt of 5,5'"'"'-Azobis-1H-tetrazole, and monoammonium salt of 5-Nitramino-1H-tetrazole.

5. A gas generant composition useful for inflating an automotive air bag passive restraint system comprising a mixture of:

a high-nitrogen nonazide fuel selected from the group consisting of tetrazoles, triazoles, salts of tetrazoles, and salts of triazoles;

a second fuel selected from the group consisting of hydrazodicarbonamide and azodicarbonamide; and

phase stabilized ammonium nitrate employed in a concentration of 55-85% by weight of the gas generant composition.

6. The composition of claim 5 wherein said high-nitrogen nonazide fuel is selected from the group consisting of nitrotetrazoles and nitrotriazoles.

7. The composition of claim 6 wherein said high-nitrogen nonazide fuel is selected from the group consisting of 5-nitrotetrazole, nitroaminotriazole, and 3-nitro-1,2,4 triazole-5-one.