Autoignition Compositions

Abstract

A nitrogen-free gas generator 10 includes an autoignition composition that contains an alkali metal chlorate such as potassium chlorate as an oxidizer, a carboxylic acid such as DL tartaric acid as a fuel, and a desiccant in operable communication therewith. Gas generating systems 180 such as vehicle occupant protection systems 180 , containing the gas generator 10 , are also provided.

What is claimed is: 
     
         1 . A nitrogen-free gas generator comprising:
 a nitrogen-free auto-ignition composition consisting essentially of an alkali metal chlorate as an oxidizer provided at about 25-75 weight percent, and a carboxylic acid as a fuel provided at about 25-75 weight percent, said percentages stated by weight of the total composition; and   a desiccant in operable communication with said nitrogen-free auto-ignition composition,   wherein said nitrogen-free auto-ignition composition auto-ignites at a temperature equal to or below 200 C, and, wherein said nitrogen-free auto-ignition composition when heat aged for 648 hours at 107 C does not react with aluminum in a sealed container.   
     
     
         2 . The nitrogen-free gas generator of  claim 1  wherein said desiccant is mixed into said composition at about 10-35 weight percent of the total composition, said desiccant selected from the group consisting of zeolite, calcium oxide, and silica. 
     
     
         3 . The nitrogen-free gas generator of  claim 1  wherein said desiccant is in vapor communication with, but physically separated from, said composition, and said desiccant is provided in amounts resulting in a mass differential of about −5.0 to 5.0% of the composition after heat aging at 107 C for 400 hours. 
     
     
         4 . The nitrogen-free gas generator of claim I wherein said composition contains an extrusion aid provided at about 0.1-10 weight percent of the total gas generant composition. 
     
     
         5 . The nitrogen-free gas generator of  claim 4  wherein said extrusion aid is selected from graphite, fumed silica, and mixtures thereof. 
     
     
         6 . The nitrogen-free gas generator of  claim 1  wherein said alkali metal chlorate is potassium chlorate. 
     
     
         7 . The gas nitrogen-free generator of  claim 1  wherein said carboxylic acid is selected from tartaric acid and its isomers, succinic acid, glutamic acid, adipic acid, and mucic acid, and mixtures thereof. 
     
     
         8 . The nitrogen-free gas generator of  claim 1  wherein said carboxylic acid is DL-tartaric acid. 
     
     
         9 . A nitrogen-free gas generating system comprising:
 a gas generator comprising a composition, said composition containing an all metal chlorate as an oxidizer provided at about 25-75 weight percent, and said composition further containing a carboxylic acid as a fuel provided at about 25-75 weight percent, said percentages stated by weight of the total gas generant composition; and   a desiccant in operable communication with said composition.   
     
     
         10 . The nitrogen-free gas generating system of  claim 9  wherein said desiccant is mixed into said composition at about 10-35 weight percent of the total composition. 
     
     
         11 . The nitrogen-free gas generating system of  claim 9  wherein said desiccant is in vapor communication with, but physically separated from, said composition. 
     
     
         12 . The nitrogen-free gas generating system of  claim 9  wherein said system is a vehicle occupant protection system. 
     
     
         13 . A nitrogen-free gas generator comprising:
 a nitrogen-free auto-ignition composition containing potassium chlorate as an oxidizer provided at about 25-75 weight percent, and DL-tartaric acid as a fuel provided at about 25-75 weight percent, said percentages stated by weight of the total composition; and   a desiccant in operable communication with said composition,   wherein said nitrogen-free composition when aged for 646 hours at 107 C does not react with aluminum within a sealed container.   
     
     
         14 . The nitrogen-free gas generator of  claim 13  wherein said nitrogen-free composition further comprises zeolite. 
     
     
         15 . A nitrogen-free gas generator comprising:
 a nitrogen-free auto-ignition composition consisting of an alkali metal chlorate as an oxidizer provided at about 25-75 weight percent, and one or more carboxylic acids as a fuel provided at about 25-75 weight percent, said percentages stated by weight of the total composition;   and   a zeolite in vapor communication with said composition.