US3472713A - Fusible aromatic nitrocompound explosive composition containing particular wax as a desensitizer - Google Patents

Description

United States Patent Int. Cl. C06!) 9/64, 15/02, 3/00 US. Cl. 149-92 1 Claims ABSTRACT OF THE DISCLOSURE Explosive compositions on a basis of fusible aromatic nitrocompounds and nitramines and/ or nitric esters having incorporated therein as desensitizer a wax of a mixture of polychloronaphthalenes obtained in the chlorination and refining of naphthalene.

This invention relates to the use of soluble desensitizers for the desensitization of castable explosives prepared on a basis of aromatic nitrocompounds and nitramines and/ or nitric esters.

More particularly this invention relates to the use of waxes comprising a mixture of polychloronaphthalenes obtained in the chlorination and refining of naphthalene. for the desensitization of castable explosives prepared on a basis of aromatic nitro compounds and nitramines and/ or nitric esters and/or powdered metals and/or known desensitizers.

The aforesaid waxes are soluble in aromatic nitro compounds and are known under the commercial name Nibrenwaches. (Literature source: Ullmanns Encyclopadie der Technischen Chemie, publishing house Urban & Schwarze'nberg, Munich-Berlin, 1954, vol. 5, page 474.) Nibrenwachs here is a mixture of polychloronaphthalenes. The production of these mixtures of isomeric polychloronaphthalenes is mentioned, for example, in the US. Patent 1,111,289 and in the German Patent 548,260 (compare Ullmann, page 474).

It is known that castable explosives prepared on a basis of aromatic nitro compounds and nitramines and/ or nitric esters can be desensitized by the addition of waxes thereto; for exacple, 1% wax is often added to Composition B (60 parts hexogen, 40 parts trinitrotoluene) and also to the Pentolite mixture (50 parts pentaerythritol tetranitrate and 50 parts trinitrotoluene). The latter wax is not soluble in molten TNT. In order to form a stable emulsion of the explosive and wax, emulsifying aids are often added, as for example, lecithin as an emulsifier and nitrocellulose as a stabilizer.

In addition, waxes and the necessary accompanying emulsifying aids are frequently added to metalcontaining explosive mixtures, such as, for example, a mixture of The use of such waxes and the accompanying emulsifying aids, however, is associated with disadvantages. Since wax, lecithin and nitrocellulose are natural substances or derivatives of natural substances, their characteristics can- 3,472,713 Patented Oct. 14, 1969 not always be precisely controlled and accordingly the formation of a stable emulsion is not always assured. Furthermore, the waxes used hitherto were characterized by a low density, so that the resultant density of the entire explosive mixture was lowered.

These disadvantages can be eliminated by employing as desensitizer soluble waxes, that is waxes soluble in the explosive mixture. The solubility of the desensitizer waxes make it possible to proceed without resorting to an emulsion, the latter being often quite difficult to prepare. Furthermore, the aforesaid soluble waxes having high densities and namely densities in the range of 1.5 to 1.7 g./ cm.

It is most surprising that, in comparison to the other waxes, and namely the insoluble waxes, a better desensitization to rapid heating is achieved by the use of the soluble Waxes, while desensitization to shock and impact is substantially equal to that realized with the waxes used hitherto.

The desensitizing effect of the wax additives, in accordance with the invention as compared to the insoluble waxes, was measured in the following manner: 0.4 g. of an explosive mixture without wax or with an insoluble or soluble wax was placed in a glass reaction vessel either in the form of a single piece or in a finely ground state. The glass vessel was then immersed in a molten bath of Woods metal. The molten metal bath was then adjusted to a constant predetermined temperature. The time it took to produce flashing or explosion of the mixture was then determined. The longer the period of time, the more tolerant the explosive mixture is of thermal stresses.

EXAMPLE 1 The time required to produce flashing or explosion of TNT with and without desensitizers, was measured at 340 C. The following data were obtained:

Seconds parts TNT 74 30 parts TNT, 5 parts Nibrenwachs D 116 (softening point: 113 C.; dropping point: 116 C.; specific density: 1.66 g./cm. content of chlorine:52

54%) 82 30 parts TNT, 5 parts Nibrenwachs D (softening point: 130 C.; dropping point: 132 C.; specific density: 1.73 g./cm. content of chlorine: 57- 59%) 82 30 parts TNT, 5 parts Montan wax 35 The above example clearly establishes that Nibrenwachs, when used according to the invention, acts as a better desensitizer than Montan wax. Montan wax, although it is a desensitizer against shock and impact, acted to reduce the time considerably for explosion to occur.

EXAMPLE 2 In the case of explosive mixtures of TNT and aluminum powder, the following times were measured at 340 C. for flashin or explosion to take place.

30 parts TNT, 33 parts powdered aluminum, parts Nibrenwachs D 116 N (softening point 116 C.) 65

This example, too, clearly demonstrates an improvement in the desensitizing action when Nibrenwachs is used.

EXAMPLE 3 The desensitizing action of the Nibrenwachs against thermal stresses in explosives of the Composition B type is readily apparent. The Montan wax content was increased to 5 parts and the mixture again tested. However, the time of 32 seconds would not be improved on at this temperature.

EXAMPLE 4 In the case of explosive mixtures of TNT, hexogen and powdered aluminum, the following times were measured at 235 C. for producing flashing or explosion. In addition, the following specific weights were determined:

Time

Spec. Wt. (seconds) 35 parts TNT, 40 parts hexogen, 25 parts powdered aluminum 30 parts TNT, 40 parts hexogen, 25 parts powdered aluminum, 5 parts desensitlzer, consisting of: 4.2 parts parailln wax, 0.7 parts nitrocellulose, 0.1 part part lecithin 30 parts TNT, 40 parts hexogen, 25 parts powdered aluminum, 5 parts Nibrenwachs D 130 30 parts TNT, 40 parts hexogen, 25 parts powdered aluminum, 4.5 parts Nibrenwachs D 130, 0.5 parts paraifin wax The desensitizing action and the improvement in density brought about by the addition of Nibrenwachs are clearly apparent in this example. The simultaneous use of soluble Nibrenwachs and of emulsion-forming paraffin wax improves the casting properties somewhat, without, however, reducing safety from thermal stress.

EXAMPLE 5 The following times were determined for explosive mixtures of tetryl and TNT (tetrytol) at 230 C. for producing flashing or explosion:

Seconds 70 parts tetryl, 30 parts TNT 28 69 parts tetryl, 30 parts TNT, 1 part Montan wax 32 69 parts tetryl, 30 parts TNT, 1 part Nibrenwachs D EXAMPLE 6 In the case of explosive mixtures of TNT and nitropentaerythrite [=PETN], the following times were determined at 230 C. for producing flashing or explosion:

Seconds 50 parts TNT, 50 parts nitropentaerythrite 27 50 parts TNT, 49 parts nitropentaerythrite, 0.84 parts paraffin wax, 0.14 parts nitrocellulose, 0.02 parts lecithin 31 50 parts TNT, 49 parts nitropentaerythrite, 1 part Nibrenwachs D 116 35 4 EXAMPLE 7 Explosive mixtures of tetryl, trinitrobenzene and hex0-' gen were prepared and evaluated for the time required at 230 C. to produce flashing or explosion. The following data were obtained:

Seconds 16 parts tetryl, 24 parts trinitrobenzene, 60 parts hexogen 45 16 parts tetryl, 24 parts trinitrobenzene, 59 parts hexogen, 1 part Montan wax 44 16 parts tetryl, 24 parts trinitrobenzene, 59 parts hexogen, 1 part Nibrenwachs D 55 The improvement in the desensitization produced by the use of Nibrenwachs in accordance with the invention is readily apparent from Examples 5 to 7.

We claim:

1. An explosive composition comprising a fusible aromatic nitro compound selected from the group consisting of trinitrotoluene, 2,4,6 trinitrophenylmethylnitramine, and trinitrobenzene and a wax as desensitizer consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene.

2. An explosive composition according to claim 1 additionally containing at least one member selected from the group consisting of nitramines, nitric esters and powdered metals.

3. An explosive composition according to claim 1 comprising 30 parts trinitrotoluene and 5 parts of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 130 C.

4. An explosive composition according to claim 1 comprising 30 parts trinitrotoluene, 33 parts powdered aluminum and 5 parts of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 116 C.

'5. An explosive composition according to claim 1 comprising 39 parts trinitrotoluene, 60 parts cyclotrimethylenetrinitramine, and 1 part of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 116 C.

6. An explosive composition according to claim 1 comprising 30 parts trinitrotoluene, 40 parts cyclotrimethylenetrinitramine, 25 parts powdered aluminum, and 5 parts of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 130 C.

7. An explosive composition according to claim 1 comprising 69 parts, 2,4,6 trinitrophenylmethylnitramine, 30 parts trinitrotoluene and 1 part of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 130 C.

8. An explosive composition according to claim 1 comprising 50 parts trinitrotoluene, 49 parts pentaerythritol tetranitrate, and 1 part of a wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 116 C. i

9. An explosive composition according to claim 1 comprising 16 parts tetryl, 2,4,6 trinitrophenylmethylnitramine, 24 parts trinitrobenzene, 59 parts cyclotrimethylenetrinitramine, and 1 part of a Wax consisting of a mixture of polychloronaphthalenes obtained in the chlorination and refinement of naphthalene, having a softening point of 130 C.

10. An explosive composition according to claim 1, wherein said wax is present in a ratio of 1 part wax: 5

to 100 parts explosive components comprising a fusible aromatic nitro compound and mixtures thereof with at least one member of the group of nitramines, nitric esters and powdered metals.

11. A method of desensitizing explosive compositions comprising fusible aromatic nitro compounds selected 5 6 References (Zited UNITED STATES PATENTS 2,982,641 5/1961 Dawson et al. 149-105 X 3,000,720 9/1961 Baer et al 149105 X CARL D. QUARFORTH, Primary Examiner S. I. LECHERT, Assistant Examiner.

US. 01. X.R. 171-93, 94; 149 105, 106, 107

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 3 72,713 Dated Oct. 14, 1969 ADOLF BERTHMANN and PAUL LINGENS Patent No.

Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

F- Column 1, line 29, cancel the period 'after "naphthalene" and insert a comma; column 1, lines 35-36, "Nibrenwaches." should be -Nibrenwachse.-; column 1, line 47, "exacple" should be -examp 9 SIGNED AND SEALED JUL? 1970 (SEAL) 'Attestr Edward M. Fletcher, Ir.

WILLIAM E. 'SOHUYLER. JR Amstmg Officer Commissioner of a