Classifications

• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
  • C06B21/0083—Treatment of solid structures, e.g. for coating or impregnating with a modifier
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
  • C06B21/0033—Shaping the mixture
  • C06B21/0041—Shaping the mixture by compression
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
  • C06B21/0033—Shaping the mixture
  • C06B21/005—By a process involving melting at least part of the ingredients
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B45/00—Compositions or products which are defined by structure or arrangement of component of product
  • C06B45/18—Compositions or products which are defined by structure or arrangement of component of product comprising a coated component
  • C06B45/20—Compositions or products which are defined by structure or arrangement of component of product comprising a coated component the component base containing an organic explosive or an organic thermic component
  • C06B45/22—Compositions or products which are defined by structure or arrangement of component of product comprising a coated component the component base containing an organic explosive or an organic thermic component the coating containing an organic compound
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S149/00—Explosive and thermic compositions or charges
  • Y10S149/11—Particle size of a component
  • Y10S149/111—Nitrated organic compound

Definitions

• Shaped high explosives prepared by coating a particulate crystalline explosive having a melting point of at least 203 C. with a halogenated polyethylene by mixing the crystalline explosive particles with an aqueous dispersion of discrete halogenated polyethylene particles having an average size of 0.1 to microns to distribute over the crystalline explosive particles about 2 to 8 percent by weight of halogenated polyethylene particles, mixing the halogenated polyethylene coated crystalline explosive particles with about 2 to 8 percent by weight of a second explosive having a melting point up to 105 C. and having a Trauzl lead-block expansion higher than that of trinitrotoluene and compressing the mixture at a compressive load of at least 700 kp./cm. and a temperature above the melting point of the second explosive.
• the field of the invention is explosive article shaping or treating by coating the base explosive with an organic compound.
• Gow discloses a method of desensitizing explosives wherein discrete particles of an explosive composition are coated with polytetrafluoroethylene by mixing the explosive composition particles with an aqueous dispersion of discrete polytetrafluoroethylene particles having an average size of 0.1 to 5 microns to distribute over the surfaces of the explosive composition particles 1-5 percent by weight of polytetrafluoroethylene particles and in which the coated particles are compressed to convert them to a coherent mass.
• Gow also discloses that a suitable 60 percent aqueous dispersion of polytetrafiuoroethylene is commercially available as Fluon, Grade GPI.
• Cyclonite particles coated with latex to be pressed or shaped are disclosed in the patent to Sauer.
• Baer discloses the coating of Cyclonite with dinitroethylbenzene to desensitize the explosive.
• Gardner discloses the coating of Cyclonite and Octogen with wax.
• readily pressed explosive compositions of high thermal stability consisting essentially of crystalline organic compounds having a melting point of at least 325 F. selected from the group consisting of picryl sulfone, Cyclonite and Octogen are prepared by admixing with vinylidene fluoride or hexafluoropropylene in a concentration of 1-5 percent by weight.
• the present invention is related particularly to a shaped high explosive of a high density, high strength, and high detonating velocity based upon high melting and high efiiciency components, such as cyclotetramethylenetetranitramine and cyclotrimethylenetrinitramine.
• HMX cyclotetramethylenetetranitramine
• TNT trinitrotoluene
• TNT can be cast (M.P. C.) or pressed without additives.
• the problem of shape-casting these high melting, high explosives has been solved for a long time in various ways.
• the substances were stabilized, i.e. provided with an addition of wax and shaped and compressed by means of presses in this form, as disclosed in US. Pat. 3,544,- 360.
• the Wax serves to markedly re prise the impact sensitivity, as well as serving as a binder between the explosive crystals in the structure produced by the pressing step.
• the high melting explosive components are introduced into the melt of a lower melting explosive, preferably trinitrotoluene, and shaped by casting in this pasty form.
• non-brisant binders does not always have a stabilizing effect.
• Cyclonite and Octogen shape-castings bound with a plastic a rather high impact sensitivity and firing sensitivity was surprisingly observed.
• the present invention proposes a shaped high explosive and a process for the preparation thereof, wherein the aforementioned disadvantages are avoided.
• the data relating to the explosive technology, particularly the density and the detonating velocity of the high efiiciency basic explosives are retained in their full values or remain at almost the same level, but wherein, on the other hand, the sensitivity characteristics are markedly reduced and a shaped explosive is produced having a surprisingly high mechanical strength.
• the shaped high explosive is characterized in that the basic explosive, present in crystalline form, is coated with 2-8 percent by weight of a plastic selected from the group consisting of the halogenated polyethylenes, by treatment in an aqueous dispersion of the plastic; dried; mixed with another 8-2 percent of an explosive having a melting point up to 105 C. and having a Trauzl lead-block expansion higher than that of trinitrotoluene; and exposing the composition, at temperatures above the melting point of the added explosive, to a compressive load of at least 700 kp./cm.
• a plastic selected from the group consisting of the halogenated polyethylenes
• TNT is used as the basis for the Trauzl lead-block test wherein TNT is rated as 100 percent and Cyclonite and HMX are rated as 170 percent and 153 percent respectively.
• the plastic from the group of halogenated polyethylene consists of polytetrafluoroethylene and polychlorotrifluoroethylene.
• halogenated polyethylenes include: Fluon, Grade GPI (60 percent aqueous dispersion of polytetrafluoroethylene having a particle size of 0.1 to microns): Hostaflon (polytrifiuoromonochloroethylene); Trithene (polytrifluo romonochloroethylene); Voltalef (polytrifiuoromonochloroethylene); Teflon (polytetrafluoroethylene); Hostaflon TF (polytetrafluoroethylene).
• the brisant component which does not melt above 105 C. and has a Trazul lead-block test over 100 consists of aromatic nitramines or mixtures thereof, or nitrates high in nitrogen, such as hydrazine nitrate, trinitrophenylethylnitramine, trinitrophenylmethylnitramine, trinitrochlorobenzene and mixtures thereof.
• the brisant component in this connection, exhibits the property of an active binder.
• the particulate crystalline high explosives of the present invention have a grain size of about 40 to 800 mi crons and include: cyclotetramethylenetetranitramine having a melting point of 282 C.; and cyclotrimethylenetrinitramine having a melting point of 203 C.
• the process for the production of the high efficiency explosive consists of exposing the mixture of the basic explosive coated by treatment with an aqueous dispersion of a halogenated polyethylene and then dried, and of an explosive which does not melt above 105 C. and has a higher Trazul lead-block expansion than trinitrotoluene at temperatures above the melting point of the added explosive, to a shaping pressure of at least 700 kp./cm. The pressure is maintained during the subsequent cooling period until the added, lower melting explosive has passed over from the liquid phase into the solid phase. Thereby, a space filling of more than 99.5 percent is achieved and thus the highest possible density is attained which, in turn, is the prerequisite for a high detonating velocity.
• an advantage in this connection is to select, for this purpose, as the active binder a substance having a satisfactory inherent explosive capacity and, as the plastic binder, a substance having a high density, such as polytetrafluoroethylene or polychlorotrifluoroethylene.
• the pressure range is preferably 700 kp./cm. to 2000 kp./cm.
• the firing sensitivity of the shaped explosive of this invention is surprisingly low (the explosive was subjected to a rifle bullet impact test with 6.2 x 54 mm. ammunition having a V (muzzle velocity of 1000 m./sec.). Smooth penetrations by the projectiles could be obtained without any noticeable reaction, although in accordance with experience gained otherwise with plastic-bound explosive compositions, positive firing sensitivities were to be expected.
• the percussion-sensitive grain of the high explosive Octogen is embedded in an unmeltable bond.
• the grain is first encased with the plastic and then shaped in a pressing step together with a meltable active binder.
• the impact energy of the projectile is at least partially converted into heat for melting the active binder and, by the incipient melting of the active binder. Thereby a sliding yieldability of the impact-sensitive high explosive particles is attained.
• EXAMPLE 1 900 g. of cyclotetramethylenetetranitramine (Octogen) having a grain size of 40-800 microns is introduced into 3 liters of a 1.5 percent strength aqueous dispersion of polychlorotrifluoroethylene and thoroughly agitated until the water of dispersion has become clear and the plastic material has been precipitated on the crystalline surfaces of the Octogen.
• the Octogen thus impregnated with 5 percent of synthetic resin is sucked-off, dried, and mixed with 45 g. of finely crystalline trinitrophenylethylnitramine (corresponding to 5 percent), and pressed at C.
• EXAMPLE 2 900 g. of cyclotrimethylenetrinitramine (Cyclonite) having the same grain size as set forth in Example 1 is treated in the same manner with 3 liters of a 1.8 percent strength aqueous dispersion of polytetrafluoroethylene.
• the Cyclonite thus impregnated with 6 percent of plastic is sucked-off, dried, and mixed with 36 g. (corresponding to 4 percent), of a fine crystalline mixture of 30 percent trinitrophenylmethylnitramine (tetryl) and 70 percent of trinitrophenylethylnitramine (ethyl tetryl) and pressed at 103 C.
• EXAMPLE 3 900 g. of Octogen of the same grain size as set forth in Example 1 is impregnated with a 4 percent polychlorotrifiuoroethylene, mixed with 56 g. (corresponding to 6 percent) of hydrazine nitrate and pressed at 73 C. (somewhat above the melting point of hydrazine nitrate) at a pressure of 900 kp./cm. until the mixture has cooled.
• the following data are determined: density 1.79; detonating velocity 8,900 m./sec.; Brinell hardness 26-28; compressive strength 38 kg./cm.
• no explosion is obtained with 6.5 x 57 mm. ammunition in several shots.
• EXAMPLE 4 900 g. of Cyclonite of the same grain size as described in Example 1 is prepared with 7 percent of polytetrafluoroethylene in the manner described in Example 1 and mixed with 27 g. (corresponding to 3 percent) of trinitrochlorobenzene (M.P. 82 C.) and then pressed at 84 C. at a pressure of 1,500 kp./cm. until the mixture has cooled.
• the data determined in this procedure are as follows: density 1.82; detonating velocity 8,600 m./sec.; Brinell hardness 28-30; compressive strength 48 kg./cm. When the firing sensitivity is determined in the aforementioned manner, there is no explosion or defiagration.
• a readily pressed explosive composition of high thermal stability comprising a particulate crystalline explosive having a melting point of at least 203 C. coated with about 2 to 8 percent by weight of halogenated polyethylene and admixed with a binder of about 2 to 8 percent by weight of a second explosive having a melting point up to 105 C., said particulate crystalline explosive selected from the group consisting of cyclotetramethylenetetranitramine, cyclotrimethylenetrinitramine, and triaminoguanidine nitrate and said second explosive selected from the group consisting of hydrazine nitrate, trinitrophenylmethylnitramine, trinitrophenylethylnitramine, trinitrochlorobenzene and mixtures thereof.
• composition of claim 1, wherein said halogenated polyethylene is selected from the group consisting of polytetrafluoroethylene and polychlorotrifluoroethylene.
• composition of claim 2 wherein said halogenated polyethylene particles have an average size of about 0.1 to 5 microns.
• composition of claim 1, wherein said particulate crystalline explosive has an average size of about 40 to 800 microns.
• a readily pressed explosive composition of high thermal stability comprising a particulate crystalline explosive having a melting point of at least 203 C. coated with about 2 to 8 percent by weight of halogenated polyethylene and admixed with a binder of about 2 to 8 percent by weight of a second explosive having a melting point up to C., said particulate crystalline explosive comprising an aliphatic nitramine and said second explosive comprising an aromatic nitramine.
• a shaped high efliciency explosive of high density, high strength and high detonating velocity comprising a particulate crystalline explosive having a melting point of at least 203 C. coated with about 2 to 8 percent by weight of halogenated polyethylene and bonded with a second explosive having a melting point up to 105 C., said particulate crystalline explosive selected from the group consisting of aliphatic nitramines and triaminoguanidine nitrate.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Crystallography & Structural Chemistry (AREA)
• Processes Of Treating Macromolecular Substances (AREA)
• Developing Agents For Electrophotography (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=5807061

Family Applications (1)

Country Status (3)

Cited By (10)

Families Citing this family (1)

• 1971
  • 1971-12-02 FR FR717143187A patent/FR2135534B1/fr not_active Expired
  • 1971-12-10 GB GB5739171A patent/GB1376627A/en not_active Expired
• 1972
  • 1972-04-11 US US00243080A patent/US3740278A/en not_active Expired - Lifetime

Also Published As

Similar Documents