US3110640A - New explosive compositions - Google Patents

Description

United States Patent This invention relates to new explosive compositions, more particularly it relates to compositions of high explosives andlorganic fluorine-containing compounds.

It is well known that anumber of high explosives such as cyclo trimethylene trinitramine, known in the art as RDX, are unsuitable for certain commercial and military uses because-of their sensitivity to mechanical shock. Among the expedients which have been used to overcome this disadvantage is the addition to the explosive of additives which effect a decrease in sensitivity to mechanical shock. However, this procedure is subject to the disadvantage that the addition of prior additives resulted in a pronounced reduction in explosive power and additional undesirable elfects, such as stickiness, decreased density, and others.

It is, therefore, an object of this invention to provide compositions of explosives, the compositions being less sensitive to mechanical shock than the explosive itself.

It is another object of this invention to provide explosive compositions having improved explosive power over prior art explosive compositions.

It is a further object of this invention to provide compositions of explosives and additives, the compositions having increased density over prior explosive compositions.

It has been found that the above and other objects can be accomplished by the incorporation in high explosives, such as RDX, of fluorine-containing organic compounds.

Although the reason for the above unexpected effect cannot be fully explained, it was found from observation of the experiments set forth hereinafter, as examples, that hydrogen fluoride is always formed as a reaction product when the compositions of the invention are detonated. Thermodynamic considerations indicate the desirability of a reaction resulting in the formation of this compound, for increased explosive efficiency. The increased heat of explosion of the compositions is indicative of the fact that energy is gained by the incorporation therein of organic fluorine-containing compounds.

The following examples of explosive compositions will serve to illustrate the invention but are not limiting thereof.

Example I A mixture of 1.078 grams of F-126 (ammonium perfluoro caprylate) and 5.55 grams of RDX (17 parts of F-126 to 83 parts of RDX) was dry mixed and added to 2 cc. of water. The mixture was stirred, air dried, and vacuum dried over night. The resulting composition pelleted at 15000 p.s.i. It had a heat of explosion of 1206 cal/gm. and a density of 1.72-1.73 gm./cc.

Example II A mixture was made from 20 parts of the ether made from dihydroperfluorobutanol and ATX, and 80 parts of RDX. The ether has the following formula:

FFFH HNOaHNOrHNOzH HFFF lithe 1'1 it till 0.8 gram of the ether was mixed with 3.2 grams of RDX and 3 cc. of ethylene chloride. The mixture was heated to boiling and evaporated to dryness in a vacuum. The

. the solution refluxed 3 hours.

resulting composition had a density of 1.75 and a heat of explosion of 1230 calories/gram. The above ether was prepared as follows:

5 grams of ATX (1,7-dinitroxy-2,4,6 trinitro 2,4,6- triaza heptane) were added to 30 grams of 1,1-dihydroperfluorobutanol and 10 cc. of methyl ethyl ketone and After cooling a mixture of 50 cc. of methanol and ether was added. After settling the crude product was filtered olf. Two recrystallizations from methanol gave 1.4 grams of product which had a melting point of l33.5-134.5 C.

Example III grams of RDX-H and 10 grams of fluorethene W [poly(chlorotrifluoro)ethylene] were dispersed in hot ethylene chloride, Span 85 and water, the mixture agitated and distilled to remove solvent. After cooling, filtration and drying, 96% recovery was effected. The composition pelleted at 15000 p.s.i. at 105 C. (preheated mold). It was found to have a density of 1.74 gm./cc. and a heat of explosion of 1216 cal./g. It gave a 50% impact test at 24 cm.

Example IV .3 gram of fluorethene W was placed in 15 cc. of ethylene di-chloride, allowed to swell for three days and heated with stirring until dispersed. To the above mixture was added 7 grams of RDX, .1 gram of Span 85, .01 gram of F 126 (3 M), and cc. of water. The mixture was heated to remove the solvent, cooled, filtered, and air and vacuum dried. 9.6 grams of the composition were produced. About 2 grams were pelleted in a preheated mold at 15000 p.s.i. to form apellet 1.267 cm. diam., .873 cm. long, and having a density of 1.70 gm./cc. Impact tests gave a value of 37.

Example V 1.0 gram of fluorethene W was dispersed with 0.5 gram polyvinyl chloride (dried Geon, 576-BF Goodrich Chemical) in 15 cc. of ethylene dichloride at reflux. To this mixture was added 8.5 grams of RDX and .1 gram of Span 85, followed by stirring. 100 cc. of water were added and the mixture distilled to remove solvent followed by the addition of 100 cc. of water, cooling, filtering and air drying. 9.9 grams of the explosive composition were produced. The composition pelleted at 15000 p.s.i., had a density of 1.69 and an impact sensitivity of 27-35.

Example VI A composition was made of 4.50 grams of RDX, 0.15 gram of DATT (1,7-diamyloxy-2,4,6-trinitro-2,4,6-triazaheptane), 0.35 gram of diisopropylammoniumperfluorocaproate (16039A). The composition was found to have a melting point between 79.5 and 81.5 C. It had an impact value of 27.5.

The above results demonstrate the effectiveness of fluorine-containing organic compounds as additives for producing explosive compositions of high density and reduced sensitivity to detonation by mechanical shock.

For example, the densities, heats of explosion and impact sensitivities of the compositions are quite favorable as compared to a density of 1.82, a heat of explosion of 1350 calories per gram and an impact sensitivity of 17 for RDX itself. While RDX has been used as the high explosive for illustrating the invention, the explosive compositions are by no means limited to RDX as the high explosive, as other high explosives such as PETN and others may be used. It is also obvious that the weight proportions of the various compositions are flexible and may be varied depending upon the desired property of the final explosive composition. The invention also in- 3 eludes compositions made by the incorporation of mixtures of the additives in high explosives.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

l. Explosive compositions desensitized to mechanical shock comprising cyclo trimethylene trinitramine and at least one compound selected from the group consisting of ammonium perfluoro caprylate, polychlorotrifiuoro ethylene, the ether of the formula FH HNOIHNOQHIIIOHH than H I; lirilll and 1,7-diamy1oxy-2,4,6-trinitro-2,4,6-triazaheptane with diisopropylammoniumperfiuorocaproate, the polyfluoro compounds being present in the amount of from about 4% to 25% by weight based on the weight of cyclo trimethylene trinitramine.

2. An explosive composition desensitized to mechanical shock comprising cyclo trimethylene trinitramine and ammonium perfluoro caprylate in an amount of about 20% by weight based on the weight of cyclo trimethylene trinitramine.

3. An explosive composition desensitized to mechanical shock comprising cyclo trimethylene trinitramine and polychlorotrifluoro ethylene in an amount of fiom about 4% to 11% by weight based on the weight of cyclo trimethylene trinitramine.

4. An explosive composition desensitized to mechanical shock comprising cyclo trimethylene trinitramine and the ether of the formula References Cited in the file of this patent UNITED STATES PATENTS 2,109,929 Rigby Mar. 1, 1938 2,179,605 Wesson Nov. 14, 1939 2,255,653 Dawson et a1. Sept. 9, 1941 2,592,069 Reid Apr. 8, 1952 FOREIGN PATENTS 10,667 Great Britain of AD 1887

Claims (1)

1. EXPLOSIVE COMPOSITIONS DESENSITIZED TO MECHANICAL SHOCK COMPRISING CYCLO TRIMETHYLENE TRINITRAMINE AND AT LEAST ONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF AMMONIUM PERFLURO CAPRYLATE, POLYCHLOROTRIFLUORO ETHYLENE, THE ETHER OF THE FORMULA