Cast explosive composition

Abstract

The invention relates to a cast explosive composition comprising a polymer-bonded explosive and a defoaming agent, and to a process for reducing the number and/or total volume of voids in a cast explosive composition comprising the steps of: combining a polymer-bonded explosive and a defoaming agent; and casting the explosive composition. The defoaming agent may be used for reducing the number and/or total volume of voids in a cast explosive composition and the cast explosive composition may be used in an explosive product.

1 - 16 . (canceled) 
     
     
         17 . A method for producing a cast and cured explosive composition, the method comprising vacuum casting a castable explosive composition comprising a polymer-bonded explosive in admixture with 0.01-2 wt % of a silicone-free defoaming agent and wherein said castable explosive composition contains entrained bubbles therein which become substantially removed by coalescence and egress, as facilitated by the silicone-free defoaming agent, during casting; and curing the cast; wherein said polymer-bonded explosive comprises an explosive and a polymer binder; and wherein said cast and cured explosive composition possesses a substantial absence of voids, wherein said silicone-free defoaming agent possesses the characteristic of being surface active at interfaces between bubbles and the polymer-bonded explosive and facilitating the coalescence and egress of bubbles. 
     
     
         18 . The method according to  claim 17 , wherein the defoaming agent is present in an amount of 0.03-2 wt %. 
     
     
         19 . The method according to  claim 17 , wherein said defoaming agent is present in an amount of 0.5 to 2 wt %. 
     
     
         20 . The method according to  claim 17 , wherein said defoaming agent is present in an amount of 0.25 to 1 wt %. 
     
     
         21 . The method according to  claim 17 , wherein said defoaming agent is present in an amount of 0.5 to 1 wt %. 
     
     
         22 . The method according to  claim 17 , wherein said defoaming agent is present in an amount of 0.25 to 2 wt %. 
     
     
         23 . The method according to  claim 17 , wherein the polymer-bonded explosive and the defoaming agent are combined in the presence of a solvent. 
     
     
         24 . The method according to  claim 17 , wherein the polymer-bonded explosive and the defoaming agent are combined in the absence of a solvent. 
     
     
         25 .- 27 . (canceled) 
     
     
         28 . The method according to  claim 17 , wherein the defoaming agent comprises a combination of silicone-free defoaming agent with a polysiloxane. 
     
     
         29 . The method according to  claim 17 , wherein said polymer binder is selected from polyurethane, cellulosic materials such as cellulose acetate, polyesters, polybutadienes, polyethylenes, polyisobutylenes, PVA, chlorinated rubber, epoxy resins, two-pack polyurethane systems, alkyd/melanine, vinyl resins, alkyds, self-crosslinking acrylates, butadiene-styrene block copolymers, polyNIMMO, polyGLYN, GAP, and blends, copolymers, and combinations thereof. 
     
     
         30 . The method according to  claim 17 , wherein said polymer binder comprises polyurethane. 
     
     
         31 . The method according to  claim 30 , wherein said polyurethane includes a hydroxyterminated polybutadiene. 
     
     
         32 . The method according to  claim 17 , wherein said explosive is selected from RDX, HMX, FOX-7, TATND, HNS, TATB, NTO, HNIW, GUDN, picrite, tetryl, ethylene dinitramine, nitroglycerine, butane triol trinitrate, pentaerythritol tetranitrate, DNAN trinitrotoluene, ammonium nitrate, ADN, ammonium perchlorate, energetic alkali metal salts, energetic alkaline earth metal salts, and combinations thereof. 
     
     
         33 . The method according to  claim 17 , wherein said explosive composition further comprises a metal powder. 
     
     
         34 . The method according to  claim 33 , wherein said metal powder is selected from aluminum, magnesium, tungsten, alloys of these metals, and combinations thereof, in admixture with the polymer-bonded explosive. 
     
     
         35 . The method according to  claim 17 , wherein said explosive comprises RDX. 
     
     
         36 . The method according to  claim 17 , wherein said explosive comprises RDX and said polymer binder comprises polyurethane. 
     
     
         37 . The method according to  claim 36 , wherein said RDX is in an amount in the range of about 75-95 wt % and said polyurethane binder is in an amount in the range of about 5-25 wt %. 
     
     
         38 . The method according to  claim 17 , wherein said silicone-free defoaming agent is present in an amount of about 1 wt %. 
     
     
         39 . The method according to  claim 17 , wherein said silicone-free defoaming agent is an alkoxylated alcohol. 
     
     
         40 . The method according to  claim 17 , wherein said vacuum casting is conducted under a vacuum at a pressure of less than 10 mm Hg.