Rapid Gas Generating Pyrotechnical Composition and Method for Obtaining Same

Abstract

The subject-matter of the present invention is: pyrotechnic compositions generating gases, whereof at least 95% by mass of the charges are constituted by constitutive ingredients hereinbelow: a reducing charge in the form of at least one organic nitrogen compound; an oxidizing charge in the form of at least one basic metal nitrate; and less than 30% by mass of a second oxidizing charge in the form of at least one alkaline metal perchlorate; and which are obtained via a dry roller compacting step of a pulverulent mixture essentially constituted by said powder ingredients; and also the method for obtaining such compositions. The compositions of the invention have interesting combustion speeds.

1 . A pyrotechnic composition generating gases, whereof at least 95% by mass of the charges are constituted by the constitutive ingredients hereinbelow:
 a reducing charge in the form of at least one organic nitrogen compound;   an oxidizing charge in the form of at least one basic metal nitrate; and   less than 30% by mass of a second oxidizing charge in the form of at least one alkaline metal perchlorate; and   
     which is obtained via a dry roller compacting step of a pulverulent mixture essentially constituted by said powder ingredients. 
   
   
       2 . The composition according to  claim 1 , in the form of shaped objects, granules, pellets or extruded monolithic blocks. 
   
   
       3 . The composition according to  claim 1 , wherein that said at least one organic nitrogen compound is selected from guanidine nitrate, nitroguanidine, guanyl urea dinitramide and their mixtures; in that said at least one organic nitrogen compound consists advantageously of guanidine nitrate. 
   
   
       4 . The composition according to  claim 1 , wherein that said at least one basic metal nitrate is selected from basic copper nitrate, basic zinc nitrate, basic bismuth nitrate and their mixtures; in that said at least one basic metal nitrate consists advantageously of basic copper nitrate. 
   
   
       5 . The composition according to  claim 1 , wherein that said at least one alkaline metal perchlorate is selected from potassium perchlorate, sodium perchlorate and their mixtures; in that said at least one alkaline metal perchlorate consists advantageously of potassium perchlorate. 
   
   
       6 . The composition according to  claim 1 , wherein that said at least one organic nitrogen compound is present at a rate of 45 to 65% by mass. 
   
   
       7 . The composition according to  claim 1 , wherein that said at least one basic metal nitrate is present at the rate of 15 to 35% by mass. 
   
   
       8 . The composition according to  claim 1 , wherein that said at least one alkaline metal perchlorate is present at the rate of 10 to 25% by mass. 
   
   
       9 . The composition according to  claim 1 , wherein that it is in the form of extruded monolithic blocks and in that said blocks include up to 10% by mass of a dry gel. 
   
   
       10 . The composition according to  claim 9 , wherein that said gel is selected from cellulosic gels, gels obtained from acrylic elastomers, ethylene-vinyl-acetate copolymers with high acetate rate, polyester polymers and their mixtures. 
   
   
       11 . The composition according to  claim 9 , wherein that said gel is sodium carboxymethyl cellulose gel. 
   
   
       12 . A method for obtaining a pyrotechnic composition generating gases, wherein it comprises:
 dry mixing of powders consisting for at least 95% by mass of a pulverulent reducing charge in the form of at least one organic nitrogen compound, a pulverulent oxidizing charge in the form of at least one basic metal nitrate and less than 30% by mass of a second oxidizing pulverulent charge in the form of at least one alkaline metal perchlorate; and   dry roller compacting of the resulting mixture of powders.   
   
   
       13 . The method according to  claim 12 , wherein that said powders have granulometry less than or equal to 40 μm. 
   
   
       14 . The method according to  claim 12 , wherein that it further comprises dry granulation of the compacted mixture of powders for generating granules. 
   
   
       15 . The method according to  claim 14 , wherein that it further comprises pelleting of said granules. 
   
   
       16 . The method according to  claim 14 , wherein that it further comprises mixing said granules with a gel and extruding said gel loaded with said granules. 
   
   
       17 . The method according to  claim 12 , wherein that it comprises recycling fines generated during the dry compacting phase and/or during the granulation phase. 
   
   
       18 . The method according to  claim 14 , wherein that it comprises recycling fines generated during the granulation process.