High temperature gas generant

Abstract

A propellant for a micro-gas generator, the propellant having 5-aminotetrazole, aluminum, a binder and an oxidizer and is substantially free from azodicarbonamide. This propellant substantially maintains its ballistic performance regardless of being aged at higher temperatures such as 120° C. Further, a method of manufacturing a propellant for a micro-gas generator, the method including providing a propellant mixture of 5-aminotetrazole, aluminum powder, potassium perchlorate, ethyl cellulose and fluoropolymers; adding acetone as a solvent to solvate ethyl cellulose and fluoropolymers; evaporating the acetone using a low level of vacuum until the mixture is a damp cake; and granulating and drying the damp cake forming dried propellant granules.

What is claimed is: 
     
         1 . Propellant for a micro-gas generator, the propellant comprising 5-aminotetrazole, aluminum, a binder and an oxidizer and is substantially free from azodicarbonamide. 
     
     
         2 . Propellant according to  claim 1 , wherein the oxidizer comprises potassium perchlorate. 
     
     
         3 . Propellant according to  claim 1 , wherein the binder comprises ethyl cellulose as a binder constituent. 
     
     
         4 . Propellant according to  claim 3 , wherein the binder comprises fluoropolymers as a binder constituent. 
     
     
         5 . Propellant according to  claim 4 , wherein the fluoropolymers are terpolymers of at least one of a group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE). 
     
     
         6 . Propellant according to  claim 1 , comprising 30-34% 5-aminotetrazole. 
     
     
         7 . Propellant according to  claim 1 , comprising 0.6-1.4% aluminum powder. 
     
     
         8 . Propellant according to  claim 1 , the binder comprising 0.6-1.4% terpolymers of the at least one of the group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE). 
     
     
         9 . Propellant according to  claim 2 , comprising 60-68% potassium perchlorate. 
     
     
         10 . Propellant according to  claim 5 , the binder comprising 1-3% ethyl cellulose and 0.6-1.4% terpolymers of the at least one of the group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE). 
     
     
         11 . Propellant according to  claim 1 , consisting of 30-34% 5-aminotetrazole, 0.6-1.4% aluminum powder, 60-68% potassium perchlorate, 1-3% ethyl cellulose and 0.6-1.4% terpolymers of the at least one of the group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE). 
     
     
         12 . A method of manufacturing a propellant for a micro-gas generator, comprising:
 providing a propellant mixture of 5-aminotetrazole, aluminum powder, potassium perchlorate, ethyl cellulose and fluoropolymers;   adding acetone as a solvent to solvate ethyl cellulose and fluoropolymers;   evaporating the acetone using a low level of vacuum until the mixture is a damp cake; and   granulating and drying the damp cake forming dried propellant granules.   
     
     
         13 . The method according to  claim 12 , wherein the step of granulating and drying the damp cake is the last step for making the final propellant. 
     
     
         14 . The method according to  claim 12 , further comprising
 densifying or tableting the dried propellant granules to form dry propellant tablets and re-granulating said dry propellant tablets to generate re-granulated dry propellant granules; and   passing the re-granulated dry propellant granules through a sieve in order to filter for re-granulated dry propellant granules of a desired granule diameter.   
     
     
         15 . The method according to  claim 12 , further comprising composing the propellant mixture such that it consists of 30-34% 5-aminotetrazole, 0.6-1.4% aluminum powder, 60-68% potassium perchlorate, 1-3% ethyl cellulose and 0.6-1.4% terpolymers of at least one of the group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE). 
     
     
         16 . The method according to  claim 12 , further comprising composing the propellant mixture such that it comprises 30-34% 5-aminotetrazole, 0.6-1.4% aluminum powder, 60-68% potassium perchlorate, 1-3% ethyl cellulose and 0.6-1.4% terpolymers of at least one of the group consisting of copolymers of hexafluoropropylene (HFP), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE).