Primary and secondary initiating explosives. Initiating explosives (primary and secondary), their properties

Initiating (primary) explosives easily explode in the form of detonation under minor thermal and mechanical influences and can cause the detonation of high explosive (secondary) explosives. These include:

Mercury fulminate– sensitive to a ray of fire and even to weak mechanical influences (impact, puncture, friction), poisonous. When wet, it loses its explosive properties: at 10% humidity it burns without detonating. Used in beam and impaling detonators.

Lead azide – less sensitive to mechanical stress and rays of fire than fulminate of mercury. When moisturized, it does not lose sensitivity to mechanical stress. The initiating ability is lower than that of mercury fulminate. Used in various detonators.

Lead trinitroresercinate (TNRS) – sensitive to flame; When ignited, it produces a powerful beam of fire. Impact sensitivity and initiation ability are lower than lead azide. Slightly hygroscopic. Used to increase the flammability of initiating compositions.

Water shock wave, methods for weakening its parameters. Danger zone and safe distances for the scattering of pieces and fragments of destructible material during explosions.

Shock wave (SW)– a compression wave propagating through a medium at supersonic speed, at the leading edge of which the pressure, density and temperature of the medium instantly (jumpwise) changes.

Explosion in a well.

When a charge explodes in a well filled with a liquid medium, the shock wave forms a bubble of detonation products heated and compressed to high pressure. Due to the inertia of the liquid, the gas bubble pulsates, emitting waves with each cycle, the intensity of which gradually decreases. Only the main and secondary shock waves are of practical importance.

Since the density of water is almost 800 times higher than the density of air, the intensity of hydrocarbons in water is much greater than in air. This partly explains the different effects on the well elements of the charges of cumulative cased and open-type perforators. Hydrostatic pressure affects the energy of hydrocarbons. At a pressure of 150 MPa, the energy of the shock wave is approximately 25% less than at a pressure of 0.1 MPa, and the destructive effect of the secondary shock wave practically ceases.

HCs in liquids propagate over long distances. In pipes that act as waveguides, the intensity of the shock waves decreases slowly. In uncased wells, due to uneven walls of the well, the waves attenuate faster. This must be taken into account when deciding on the permissible power of the explosion, based on the strength of the well elements at certain distances from the explosion site.

Safe shock wave distance: r=k*(Q)^1/3;

k-coefficient of proportionality, depends on the degree of damage to which we can assume - the strength of the building, its importance - a barn or the White House.

Q-mass of explosives in tratyl equivalent.

Dispersion formula:

Rtime=1250*n*(f*d/a*(1+N))

n-well filling coefficient;

N-for stopping; plug - inserted into the well so that the energy does not go into the air.

d-well diameter;

a-distance between wells during massive explosions.

f-coefficient of the rock on the strength scale.

Application of initiating explosives:

Initiating explosives used for stimulation in others BB explosive transformation in the form of combustion or detonation. Therefore, they are used to equip equipment initiation: detonator caps, igniter caps, etc.

3.Preparing the well for perforation. Certificate of well readiness for perforation. The procedure for preparing hammer drills on the surface and connecting to the cable. Lifting operations.

The head of the BP and the head of the party must sign an act in accordance with the project on preparing the well for perforation.

The well must be drilled, filled with the necessary solution (clean water, kirosene - in case of depression, in case of repression, fill with a weighted solution). There should be a passage, cleared walkways, platforms for the lift and LPS, a place for connecting to the electrical network, grounding, 75 lux at the mouth and 50 lux on the walkways, 25 lux throughout the danger zone

The report must indicate: Well design, cementation, work performed.

Places for grounding and connection to electricity, and a site for installing LPS must be provided.

Loading rotary hammers should be carried out in the LPS or on special tables with sides.

The tables must be grounded and located at a distance of 20 m from the well.

Housing rotary hammers: cleaned, inspected at the LPS. Their swelling is allowed to be 5-6 mm.

Frameless rotary hammers: charged and inspected on tables.

Pipe hammers: assembled and lowered in sections, screwed to each other.

The well must be drilled and filled with liquid, which is used for PVR.

Descent - lifting operations.

Upper suspension block for strictly vertical lowering of the cable with a hammer drill.

Loading and unloading VMs.

1. Loading and unloading of vehicles with VMs must be carried out with the utmost care in specially designated and equipped areas.

The transported cargo must be stowed in such a way as to prevent the package from falling, colliding with the vehicle or hitting the sides of the vehicle body.

2. Loading of a VM vehicle must be carried out in accordance with the cargo placement and securing schemes contained in the regulatory and technical documentation approved by the authorized head of the relevant service of the enterprise carrying out transportation. In this case, the load must be located symmetrically relative to the longitudinal axis of the body and evenly (by weight) over the entire area. Work must be carried out under the direct supervision and control of the person responsible for loading, designated by order.

3. Before the cargo is delivered for shipment, as well as during the loading process, the cargo must be carefully inspected by the shipper in order to check the correctness of the packaging, the quality of the container, the integrity of the seals and seals, the compliance of the data indicated on the cargo and in the transportation documents, which are required by the regulatory and technical documentation for VM, including markings and cargo weight.

4. The procedure for loading, reloading and unloading the vehicle must exclude the possibility of collisions with workers performing work or touching them with the load.

5. When transporting VMs separately, loading of special and specialized vehicles (see Section 6) is allowed up to their full carrying capacity, with the exception of detonators, the loading of which in all cases is permitted to no more than two-thirds of the loading capacity and no more than two boxes in height.

The total load capacity of a specially equipped vehicle is determined as the difference between the total load capacity of a production vehicle and the weight of additional equipment installed on the vehicle.

When transporting explosives and SI or SI and PVA together, the vehicle load should also not exceed 2/3 of its carrying capacity.

Boxes with VM should be laid flat, close to each other, bags - in a cage or vertically, but not higher than the level of the sides, and covered with a fabric specially designed for this purpose.

In the case of transportation of explosives in special containers approved for these purposes, the latter may protrude above the level of the sides of the vehicle.

It is allowed to transport explosive materials without packaging from warehouses to explosion sites in charging machines approved for these purposes by the State Technical Supervision Authority of Russia.

6. Vehicles intended for the transportation of explosives must be delivered to the loading (unloading) places one at a time in accordance with the requirements of the instructions for carrying out loading and unloading operations, approved by the head of the enterprise. Loaded and awaiting loading vehicles must be located at a distance of at least 100 m from the loading (unloading) points and placed in different places. Loaded vehicles should not linger near production buildings.

7. During loading and unloading operations, the vehicle engine, except for charging vehicles during the charging of wells, must be turned off, the vehicle must be braked with a hand brake, at least 2 wheel chocks must be installed under the wheels, and the driver must leave the cab.

8. When transporting explosive materials that are subject to partial unloading or loading en route, each batch of explosive materials must be secured separately.

10. It is prohibited to smoke within 50 m of vehicles intended for loading and unloading, as well as during loading and unloading operations with them.

Explosives, based on the nature of their action, are divided into the following groups.

· Initiating explosives.

· High explosives (or crushing explosives).

· Gunpowder.

· Pyrotechnic compositions.

Initiating explosives are those that have very high sensitivity and explode from minor external mechanical (impact, friction) or thermal (laser beam, flame, heat, electric current) effects. These substances always detonate and cause the detonation of other explosives. Initiating explosives are used in small quantities to fill the primers, which create the initial impulse of the explosion.

High explosives are those that, when exploded, crush surrounding objects. They are much less sensitive to external influences than initiating explosives, and usually detonate under the influence of the explosion of another explosive - a detonator. The detonator is a charge of explosive more sensitive than the explosive of the main charge. The explosion of the detonator is carried out by the explosion of a capsule with an initiating explosive (Fig. 3.1). First, the capsule explodes due to mechanical or thermal effects. The resulting shock wave causes the detonator to explode, which, when exploding, causes the detonation of the main charge. High explosives are used as explosive charges for filling mines, shells, and demolition cartridges and are used to destroy and crush various objects and obstacles.

Rice. 3.1. High explosive detonation diagram:

1 – primer (initiating explosive); 2 – detonator;

3 – main charge of high explosive

Gunpowders are those explosives whose nature of explosion allows them to be used as a source of energy for the movement of projectiles, mines, bullets and rockets. The main type of explosive transformation of gunpowder under normal conditions is faster combustion. Gunpowder is not sensitive to external mechanical influences. The difference in the effects of gunpowder and high explosive can be illustrated by a simple example shown in Fig. 3.2. With the rapid burning of gunpowder (Fig. 3.2, a), the gas pressure increases gradually, the projectile moves with acceleration, crashing into the rifled channels (which serve to impart a rotational movement to the projectile in order to stabilize its trajectory). When a high explosive is detonated (Fig. 3.2, b) under the same conditions, gas formation occurs almost instantly, and the resulting gases destroy the barrel and chamber.

Rice. 3.2. Scheme of the action of an explosive on a projectile during combustion:

A – gunpowder; b – high explosive

Pyrotechnic compositions are mixtures of explosive and non-explosive substances. Their explosive properties are much less pronounced than those of conventional explosives. Pyrotechnic compositions have special properties (bright glow, smoke formation, flame color). They are used in lighting and incendiary cartridges, in fireworks and fireworks, in smoke bombs, etc. Let us consider in more detail the main types of explosives.

Initiating explosives

The most commonly used initiating explosives are mercury fulminate, lead azide and lead styphnate.

Mercury fulminate - mercury fulminate, is a finely crystalline white or gray powder. It is obtained as a result of the action of ethyl alcohol on a solution of mercury in nitric acid. Uncompressed mercury fulminate is extremely dangerous to handle because it is very sensitive. In compressed form, this substance is less dangerous and less sensitive to initial stimulation. Under the influence of moisture, mercury fulminate easily loses its explosive properties. At 5%moisture, the explosive properties are reduced, at 10% it only burns, at 30% it turns into an inert substance.

Lead azide is a lead salt of hydronitrous acid and is a white powder. It is less sensitive than mercury fulminate, but has an initiating ability 10 times greater than mercury fulminate. It is not hygroscopic and does not dissolve in water. It is used in aluminum shells, as it does not react with aluminum. When interacting with copper, it forms copper azide, a very sensitive explosive.

Lead styphnate (TNPC) is the lead salt of styphnic acid. TNPC is a solid, yellow, fine-crystalline substance. It is not hygroscopic, does not dissolve in water and does not interact with metals. Sensitivity to impact is lower than that of lead azide, and sensitivity to flame is higher. Very sensitive to electrical discharges. Its initiating ability is lower than that of other initiating explosives.

Initiating explosives, when mixed with other substances, form impact compounds that are used to equip igniter caps and detonator caps. Recipes of some impact compositions are given in table. 3.2.

Mercury fulminate in shock compositions gives the initial flash, antimonium is flammable and serves to increase the force of the flame, Berthollet salt is an oxidizing agent that supports combustion. Igniter capsules are divided into cartridge and tube.

Cartridge primers are used in cartridges and primer bushings for small arms and artillery shells. They are ignited by the impact of the striker and provide the initial impulse for igniting the warhead. The diagram of the cartridge igniter primer is shown in Fig. 3.3.

Table 3.2

Recipes for impact compounds for rifles and pistols

primer igniters

Primer-igniter	Mercury fulminate, wt.%	Bertholet salt, wt.%	Antimonium, wt.%	Massa, city
Pistol				0.02
Rifle				0.03
Capsule sleeve				0.025

Rice. 3.3. Schematic of cartridge igniter primer

It consists of a metal shell (cap) 1, made of brass or copper, into which the impact composition 2 is pressed. The impact composition is closed on top with a foil or paper circle 3. Tube igniter capsules are used in tubes and fuses and serve to initiate the detonation of the detonator capsule .

The diagram of the tube igniter capsule is shown in Fig. 3.4.

Rice. 3.4. Diagram of a tube primer-igniter:

1 – cap with a hole; 2 – shock composition;

3 – foil cup; 4 – foil diaphragm

To equip tube igniter primers, the same impact composition is used as for cartridge igniter primers, but its mass is (5 ÷ 10) times greater and amounts to (0.08 ÷ 0.2) g.

Detonator caps are divided into artillery and demolition caps. Artillery detonator caps are used in fuses of various shells, mines, aerial bombs and hand grants. The purpose of a blasting cap is to cause the detonator of the explosive charge of the high explosive with which the charge is loaded to detonate.

Depending on the nature of the initial impulse that initiates the explosion, detonator capsules can be of the following types.

· Impaled, they act by being pricked with a sting.

· Beam, operate from the beam (force) of the fire of the igniter primer.

· Detonator caps are designed to initiate the detonation of explosive charges. They operate from a fire force (bikeford cord) or from an electric igniter. The diagram of the blasting cap-detonator is shown in Fig. 3.5.

Rice. 3.5. Scheme of a blasting cap-detonator:

1-sleeve; Lead 2-styphnate; 3-lead azide; 4-tetryl

High explosives

High explosives are used to fill artillery shells, mines, hand grenades, aerial bombs, and also to prepare demolition agents. The main high explosives currently used are pyroxylin, nitroglycerin, TNT, melanite, hexogen, dynamite, as well as various mixtures and alloys.

Pyroxylin (nitrocellulose) is a solid substance with a fibrous structure. It is obtained by treating plant fiber (cotton, flax, wood) with a mixture of nitric and sulfuric acid - nitration or nitration of fiber. Depending on the degree of nitration, the nitrogen content in pyroxylin may vary. The higher the nitrogen content, the higher the explosive properties of pyroxylin. Pyroxylin is very hygroscopic. When the moisture content is up to 3%, pyroxylin is called dry, and when the moisture content is more than 3%, it is called wet. Dry pyroxylin is very dangerous - it explodes on impact and friction. With a moisture content of more than 25%, it is insensitive and safe to handle and store. Pyroxylin is used to make smokeless powder and for blasting. For loading ammunition, pyroxylin No. 1 (13% nitrogen) and pyroxylin No. 2 (12% nitrogen) are used.

Nitroglycerin is a poisonous clear oily liquid. It is obtained by treating glycerin with nitric and sulfuric acid. Very sensitive to shock, friction, shock. It is not used in its pure form. It is used in the manufacture of smokeless powders as a solvent and for the preparation of dynamite in blasting operations.

TNT (trinitrotoluene, tol, TNT) is a solid, finely crystalline substance of dark yellow color. It is obtained by treating toluene (a product of dry distillation of coal) with nitric and sulfuric acid. TNT is insensitive to shock and heat, is safe to handle and has a high shelf life (blocks retain the ability to explode even after decades of storage). In the open air it burns with a smoky flame without explosion. TNT is the most common explosive. It is used for loading shells, mines, bombs and in demolition work.

Melinite (picric acid) is a dense crystalline mass of yellow-lemon color. It is obtained from carbolic acid by treating it with nitric and sulfuric acids. It is a stronger explosive than TNT. The disadvantage is the ability to form chemical compounds (salts) at the junction with metal shells - picrates, very sensitive to impact and friction. Used for preparing demolition charges.

Hexogen is obtained by treating methenamine and pentaerythritol with nitric acid. It is the most powerful high explosive. Hexogen is a crystalline white substance that melts well and does not interact with metals. This is a more powerful explosive than TNT and melinite, but also more sensitive to mechanical stress. Phlegmated RDX is used to equip armor-piercing and anti-aircraft projectiles and for the manufacture of additional detonators.

Ammonites (explosives based on ammonium nitrate) are surrogate explosives, which are made from a mixture of ammonium nitrate, TNT, aluminum powder and other fillings. They are inferior in explosive action to TNT, are of little use for storage and are usually used only in wartime (cheap raw materials). In the USSR during the Great Patriotic War, ammonites were the main types of explosives. In peacetime, they are used in the national economy (exploding ice jams, coal seams in mines, etc.). Two types of ammonites are used for hand grenades - ammotol (a mixture of ammonium nitrate and TNT) and ammonal - a mixture of ammonium nitrate, high explosive and aluminum powder.

Plastit-4 (C-4) is a dough-like mass of a cream or brown color (less often bright orange). It consists of 80% powdered hexogen and 20% plasticizer (which determines its properties). In appearance it resembles plasticine or wax, it is oily to the touch, plastic in temperature conditions from -30° C to +50° C. Just like TNT, it is very resistant to external influences - it can be crushed, cut, dropped, or subjected to impacts without dangerous consequences. The special properties of plastite determine its use for terrorist purposes - a charge of plastite can be placed in any gap, rolled out in a thin layer into a letter, or hidden in a structure of any configuration. It is used, most often, in some kind of shell (paper, bag) and attached with adhesive tape or tape to the object to be exploded. Plastit-4 is supplied in standard briquettes weighing 1 kg, wrapped in paper. Plastite charges are used in the active armor of tanks, as well as for equipping MON-50 anti-personnel mines.

Gunpowder

Gunpowders, or propellant explosives, are explosives for which the main form of explosive transformation is rapid combustion at a speedu in» (1÷10) m/s. Gunpowder is used as a source of energy for the movement of projectiles, bullets, mines, and rockets. In addition, gunpowder is used as auxiliary means - igniters, gas generators, etc.

Gunpowders are divided into two groups - mechanical mixtures and colloidal gunpowders.

Mechanical mixtures include the following compositions.

· Black powder.

· Ammonium powder.

· Mixed high-energy materials and solid rocket fuels.

The basis of all colloidal powders is pyroxylin. Depending on the nature of the solvent, colloidal powders are divided into the following groups.

· Pyroxylin powder (volatile solvent).

· Nitroglycerin powder (using a non-volatile solvent).

· TNT powder (in a non-volatile solvent).

· Viscose powders (without solvent).

Mechanical mixtures

Black or black powder is a mechanical mixture of potassium nitrate, sulfur and charcoal (S, KNO3, C). For more than 500 years, black powder was the only explosive used in warfare for the manufacture of charges in artillery and small arms and for demolition. Only in the second half of the 19th century did they begin to use pyroxylin gunpowder instead of black powder for war charges. The most optimal composition of black gunpowder was established at the end of the 18th century based on the works of M.V. Lomonosov. The composition of black powder is given in table. 3.3.

Table 3.3 Composition of black powder Substance Potassium saltpeter Sulfur Woody coal

This composition has not changed significantly to date. When heated, saltpeter easily releases oxygen, which is necessary for the combustion of coal and sulfur. With increasing saltpeter content (up to 80%), the strength of the gunpowder and its burning rate increase. Coal in gunpowder is a flammable substance.

As its content increases, the burning rate of gunpowder decreases. Sulfur is a cementing agent that binds saltpeter to coal, as well as a flammable substance that facilitates the flammability of black gunpowder (sulfur ignites at a lower temperature than coal). As the sulfur content increases, the burning rate and strength of the gunpowder decreases. Black gunpowder is obtained by thoroughly mixing the crushed components, pressing the mixture and crushing the pressed cake into grains of various sizes. Gunpowder is sensitive to all types of mechanical influence (impact, friction, spark, etc.). When a bullet hits a powder charge, it almost always explodes. However, black powder does not detonate. When black gunpowder burns, 45% of gaseous and 55% of solid products are formed (smoke, carbon deposits in the barrel bore). Currently, black gunpowder is not used in combat charges (low powder strength, unmasking by smoke, dangerous to handle, hygroscopic). It is used for the manufacture of igniters, as well as in the fuses of hand grenades.

Ammonium gunpowder consists of ammonium nitrate (90%) and charcoal (10%). It is obtained by mixing the components and pressing into elements of a given shape (rings, segments). Ammonium powder is a gray solid. Unlike black powder, all of its combustion products are gaseous. Sensitivity to mechanical influences is weak. Very hygroscopic and unsuitable for storage. Used in wartime to replace (25÷35)% of the charge of pyroxylin gunpowder.

Mixed high-energy materials and mixed solid rocket fuels (MSRP) represent a wide class of energy-intensive substances used as energy sources in gas generators for various purposes and in solid fuel rocket engines. The composition of SRT includes a polymer fuel-binder (butyl rubber), an oxidizing agent (ammonium perchlorate or ammonium nitrate) and a metal fuel (powdered aluminum).

Colloidal powders

Pyroxylin smokeless powder is made from a mixture of two types of pyroxylin - No. 1 and No. 2 in different ratios. A mixture of these varieties is dissolved in an alcohol-ether mixture. The resulting homogeneous jelly-like mass is pressed through special filters. After cutting and drying, powder grains are obtained (belt, tubular, cylindrical, multi-channel gunpowder). Up to 3% of impurities are added to the composition of pyroxylin powder - stabilizers, phlegmatizers and flame arresters. Stabilizers (diphenylamine) slow down the decomposition of gunpowder and increase the shelf life to 20 years (without stabilizers, gunpowder is stored for 10 years). Phlegmatizers (camphor) reduce the burning rate. Flame arrestors (rosin, dibutyl phthalate) reduce the flame when fired. They absorb part of the energy of the gunpowder and reduce the temperature of the combustion products. D.I. made a great contribution to the development of smokeless powders. Mendeleev. Pyroxylin powder has a number of advantages over black gunpowder.

· Has higher energy.

· When burned, it does not form smoke or soot in the gun barrel (98.5% are gaseous products).

· Allows the production of charges of various sizes and shapes, which makes it possible to regulate the duration of charge burning.

· Has low hygroscopicity.

· Retains its properties during long-term storage and is insensitive to shock.

Nitroglycerin smokeless powder is made from pyroxylin, and nitroglycerin is used as a solvent. Depending on the brand of pyroxylin, ballistites (pyroxylin No. 2) and cordites (pyroxylin No. 1) are distinguished. The advantages of nitroglycerin powders over pyroxylin powders are as follows:

· Higher powder strength values.

· Less time spent on their production – (5÷7) hours instead of several days.

· Low cost.

· Better preservation of properties during storage.

· They are used for mortars, multiple launch rocket systems, and solid fuel rocket engines.

TNT gunpowder is made from a mixture of pyroxylin and TNT. Gunpowder is obtained by special processing at elevated temperatures and high pressure. There is no volatile solvent in it, so TNT powder is more stable in quality than pyroxylin and nitroglycerin powders. Recently it has been increasingly used.

Viscose powder (solventless powder) is a nitrated and stabilized pre-compacted cellulose. These gunpowders are still poorly studied. Used for making charges for rifles and pistols.

Pyrotechnic compositions

Pyrotechnic compositions are used to equip special projectiles, bullets, rockets, and so on. Many pyrotechnic compositions are explosives, but their explosive properties are much less pronounced than those of conventional explosives. The energy released during the combustion of pyrotechnic compositions is spent not on the production of mechanical work, but on the formation of a pyrotechnic effect (illuminating the area, initiating a fire, etc.). Pyrotechnic compositions are mechanical mixtures of fuel, oxidizer, cementing agent and special impurities. Aluminum, magnesium, their alloys, gasoline, kerosene, oil, turpentine, starch, etc. are used as fuel. As oxidizing agents - salts of nitric, perchloric and perchloric acid, metal oxides (iron oxide, barium peroxide, manganese dioxide and etc.). As cementators – drying oil, rosin, shellac, artificial resins (bakelite, etc.). They serve to bind the composition and give it mechanical strength. Special impurities serve to color the flame or smoke.

Based on the nature of their application, pyrotechnic compositions are divided into the following groups.

· Lighting.

· Incendiary.

· Signal.

· Smoke.

· Tracers.

Lighting compositions are used to equip illumination cartridges, shells and aerial bombs and serve to illuminate the area or individual objects. The most common composition is 18% aluminum, 4% magnesium, 75% barium nitrate, 3% drying oil. Lighting compositions are pressed into a cylindrical shell, on one side of which the igniting composition (black powder) is pressed. The diagram of the lighting socket is shown in Fig. 3.6. The characteristics of some lighting compositions are given in table. 3.4.

Table 3.4

Characteristics of some lighting compositions

Ammunition	Light intensity, thousand candles	Action time, s
Cartridge
Projectile
Air bomb

Incendiary compounds are used to load bullets, shells and aerial bombs. They are divided into three groups.

· Thermite-incendiary compositions containing metal oxides as an oxidizing agent.

· Incendiary compositions are oxygen-containing mixtures (salts).

· Incendiary compositions that do not contain an oxidizer.

Rice. 3.6. Light socket diagram:

1–sleeve; 2–capsule; 3–charge of black powder;

4–ignition composition; 5–lighting composition; 6-wad

Thermite-incendiary compositions are made on the basis of thermite (a mixture of 25% aluminum and 75% iron oxide) with a combustion temperature of about 2500 ° C. Thermite is not used in its pure form, since it has a small ignition radius. An example of a thermite incendiary composition for a 76 mm projectile is given in Table. 3.5.

Table 3.5

Composition of thermite incendiary projectile

Substance	Barium nitrate	Potassium nitrate	Iron oxide	Aluminum	Magnesium	Cementator

Incendiary compositions with an oxidizer in the form of various salts give a high combustion temperature and are easily ignited. These compounds are used to equip incendiary small-caliber projectiles and bullets. Incendiary compositions without an oxidizer burn due to oxygen in the air. As an example, let's take an aerial bomb with an electron body (an alloy of 92% magnesium and 8% aluminum) filled with a thermite composition. When such a bomb burns, the temperature reaches (700 ÷ 900) ° C and hot sparks are formed, which scatter over a long distance.

Incendiary compounds include hardened fuel (napalm) - a gelatinous mass obtained by mixing stearic acid and an alcohol solution of caustic soda with petroleum products. It ignites easily and produces a bright, voluminous flame.

Self-igniting substances - white phosphorus and mixtures with it easily ignite in air ( T » 1000° C). An example of the use of this substance is bottles for setting fire to tanks, which were widely used during the Great Patriotic War (“Molotov cocktail”). They contain fuel and phosphorus dissolved in carbon disulfide. When the solvent evaporates, phosphorus ignites in air, and first carbon disulfide vapor is ignited, and then the main fuel.

Signal compositions produce a colored flame when burning, for example red, yellow, green, white. Signal compositions with a blue flame are not used, since the blue flame is poorly visible at a great distance. To obtain a red flame, strontium compounds are added to the composition, green flame - barium compounds, yellow - sodium salts, white - barium and potassium salts. To increase brightness, up to 5% aluminum or an aluminum-magnesium alloy is added to signal compositions. Signal compounds are used in 26 mm cartridges (rocket launchers). The rocket's lifting height is 90 m, the charge burning time is 6.5 s, and the luminous intensity of the flame is 10,000 candles.

Smoke compositions are designed to camouflage objects and smoke enemy battle formations. Used for equipping smoke bombs, shells, mines. Based on the nature of the smoke formation process, they are divided into three groups.

· Smoke formation as a result of combustion.

· Smoke formation as a result of interaction of the composition with air moisture.

· Smoke formation as a result of thermal sublimation.

The first group includes white phosphorus. At a temperature of +50° C, it ignites and burns with the formation of thick white smoke. The second group includes sulfur trioxide, tin tetrachloride, and chlorosulfonic acid. The third group includes smoke bombs (Ershov bombs), which consist of potassium nitrate (10%), ammonium chloride (40%), berthollet salt (20%), charcoal (10%), naphthalene (20%). When Ershov's mixture is burned, ammonium chloride and naphthalene sublimate, the condensation of vapors of which leads to the formation of smoke.

Tracer compounds serve to indicate the flight path of a bullet or projectile (white or red trace). Examples of tracer compositions are given in table. 3.6.

Pyrotechnic compositions, along with the examples of military applications discussed above, are widely used as charges for equipping rockets and pyrotechnic devices during fireworks displays, organizing colorful fireworks and other festive shows. The pyrotechnic charges used in this case are a combination of various compositions.

Table 3.6

Composition of tracer mixtures

Tracer composition	Substance
White route	Barium nitrate
	Magnesium
	Shellac
Red route	Strontium nitrate
	Magnesium (aluminum)
	Cementator

Initiating explosives have the greatest sensitivity to external influences. The development of the detonation process in them, i.e. the establishment of detonation speed, occurs in a very short period of time, almost instantly, and therefore they are capable of detonating in very small quantities (on the order of tenths of a gram) from such simple initial impulses as a spark, a ray of flame , puncture, exciting an explosive transformation in other, less sensitive substances.

The very high sensitivity and weak explosive characteristics of initiating explosives do not allow their use as main explosives to obtain mechanical work from them.

Mercury fulminate is obtained from metallic mercury by treating it with nitric acid and ethyl alcohol in the presence of certain additives (hydrochloric acid and copper filings). As a result, after

Washing produces a white crystalline powder, very sensitive to all kinds of external influences, and therefore requiring extremely careful handling.

When moistened, mercury fulminate loses its explosive properties; at a moisture content of 10% it only burns and does not explode, and at 30% humidity it does not even light up.

In acids and alkalis, mercury fulminate decomposes, and concentrated sulfuric acid causes it to explode.

It practically does not interact with metals, only with aluminum it reacts vigorously, releasing heat and forming non-explosive compounds. Mercury fulminate can only react with copper, from which detonator cap sleeves and igniter caps are made, only in the presence of moisture, but chemical reactions proceed extremely slowly with the formation of copper fulminate, a substance more sensitive to friction, impact and heat.

Changes in temperature within the limits of its normal fluctuations do not affect the stability of mercury fulminate, but prolonged heating at temperatures above +50 ° C leads to its decomposition and loss of its explosive properties. At temperatures below -100° C, mercury fulminate also loses its explosive properties.

Mercury fulminate is currently used only for equipping detonator caps and electric detonators and in primer compositions used to equip igniter caps.

Lead azide is obtained from metallic sodium and lead as a result of their interaction with ammonia and nitric acid. Lead azide is the only explosive used that does not contain oxygen. It is a white, finely crystalline powder, non-hygroscopic. When exposed to moisture, it does not reduce its sensitivity and ability to detonate. However, in the presence of moisture and at elevated temperatures, lead azide reacts with metals to form metal azides (such as copper azide), which are many times more sensitive than lead azide.

Acids, alkalis, carbon dioxide (especially in the presence of moisture) and sunlight slowly decompose lead azide. Temperature fluctuations do not affect its durability, but when heated to 200°C it begins to decompose.

Lead azide, compared to mercury fulminate, is less sensitive to spark, flame beam and impact; but the initiating ability of lead azide is higher than that of mercury fulminate. For example, to initiate one gram of tetryl, 0.29 g of mercury fulminate and only 0.025 g of lead azide are needed.

Lead azide is used to equip blasting caps and electric detonators.

Teneres [C6H(NO2)3O2PbH2O], abbreviated TNPC, is the lead salt of styphnic acid and is called lead styphnate or lead trinitroresorcinate. It is a finely crystalline powder of golden yellow color, slightly hygroscopic and does not interact with metals. Acids decompose it. When exposed to sunlight, teneres darkens and decomposes. Temperature fluctuations have the same effect on teneres as on lead azide.

47. Depending on the application, explosives are divided

Depending on the application, explosives are divided into three large groups: initiating, crushing, propellant (powder).

Initiating Explosives differ in that the usual form of their explosive transformation is complete detonation. Initiating explosives are the most sensitive to external influences and easily explode from a minor impact, puncture, flame ray, etc. They are used primarily for the manufacture of all kinds of igniters and equipment of primers used to initiate explosive transformations of other explosives. To equip cartridge igniter capsules, a percussion composition (a mixture of fulminate of mercury, berthollet salt and antimony) is mostly used.

Initiating explosives include:

Mercury fulminate;

Lead azide;

TNRS (lead trinitroresorcinate, lead styphnate).

Crushing (blasting) Explosives are those that, despite being relatively safe to handle, detonate without failure. They are detonated with primers of initiating explosives. The speed of explosive transformation of high explosives reaches several hundred meters per second. They are used as explosive charges for shells, aircraft bombs, mines and grenades.

High explosives are divided into 3 groups:

A) High power explosives ( PETN (tetranitropentaerythritol, penthrite); RDX (trimethylenetrinitroamine); tetryl (trinitrophenylmethylnitroamine);

b) Explosives of normal power(TNT (trinitrotoluene, tol, TNT); picric acid (trinitrophenol); plastic explosives (plastids);

V) Low power explosives(ammonium nitrate; ammonium nitrate explosives (ammonites, dynamites).

Also classified as high explosives are nitroglycerin and others.

Nitroglycerine is an oily, colorless liquid. Its properties are quite unstable and can detonate upon impact, so it is not used often.

Dynamite is an absorbent material soaked in nitroglycerin. After that, it is wrapped in polished paper. Over time, drops of liquid nitroglycerin appear on its surface, and it becomes less stable. When nitroglycerin begins to release from it, the bars turn into a greasy mess and become very dangerous to handle. Most other explosives also "sweat" and wet spots on a bag are a sure sign that it may contain an explosive device.

Throwing BB, or gunpowder , are called those whose explosive transformations are in the nature of rapid combustion, mostly occurring at a speed of several meters per second. Gunpowder is used in all types of firearms as a source of energy necessary to impart movement to the bullet (projectile). Therefore, of all types of explosives, gunpowder is of the greatest interest for shooting, which requires, at least in general terms, familiarization with their properties and features.

Gunpowders are divided into: smoky(mechanical mixtures) and smokeless(colloidal).

Smokey or black powder, in comparison with other types of currently known propelling explosives, is ballistically unfavorable and unproductive in terms of operation; after the explosion, its powder gases increase their volume only 280-300 times compared to the initial volume of the charge.

Can also be used as charges TNT blocks (75 g, 200 g and 400 g), boxes with TNT blocks weighing 25 kg, plastic explosive briquettes or other standard military charges (concentrated, elongated, cumulative). Depending on the purpose of the explosive device, containers with smoky and smokeless powder can be used as a charge.

Essay

New lead and mercury free initiating explosives

Introduction

initiating explosive azide oxydiazo compound

Initiating explosives are those explosives that are very sensitive and explode from minor external mechanical (impact, friction) or thermal (laser beam, flame, heat, electric current) influence. These substances always detonate and cause the detonation of other explosives. Initiating explosives are used in small quantities to fill the primers, which create the initial impulse of the explosion. For initiating explosives, the transition from combustion to detonation occurs quickly, at a distance not exceeding a few millimeters from the point of ignition. The shorter the transition from combustion to detonation and the higher the detonation speed, the higher the efficiency of initiating explosives. If you place a small amount of initiating explosive on a high explosive charge and set it on fire, its explosion will produce such a strong impact that the high explosive will also explode.

There are two main areas of application of IVV:

) To excite detonation in explosive charges.

) To sensitize igniter compositions intended to ignite powder charges or initiate detonation in the charges of the main explosive.

The most widely used initiating explosives are mercury fulminate, lead azide and lead styphnate, but this abstract deals exclusively with explosives that do not contain lead and mercury.

1.
Diazonium salts

Diazonium salts with oxidizing anions have explosive properties, and almost all aryldiazonium perchlorates are explosives. Has a high initiating ability, combined with satisfactory performance characteristics. 2,4 - dinitro-diazobenzene perchlorate (2,4 - dinitrophenyldiazonium perchlorate). The starting product for its preparation is 2,4 - dinitroaniline.

4 - Dinitrodiazobenzene perchlorate is an effective IVS, having the following properties: t sp, 5 sec = 215 o C;  = 1.65 g/cm 3, the minimum tetryl charge is 0.007 g (for comparison: mercury fulminate - 0.35 g, and lead azide - 0.025 g).

4 - Dinitrodiazobenzene perchlorate decomposes in light, but the photodecomposition products form a light-protective film, so only the surface layer decomposes and the initiating ability of the charge does not change. The product is thermally stable: the explosive properties of the substance were preserved after keeping the charges for two years at 80 o C. In the 40s of the last century, dinitrodiazobenzene perchlorate was successfully tested as an explosive for industrial pressurization. In subsequent decades, repeated attempts were made to find practical applications for this phenyldiazonium perchlorate, including as a low-toxicity IVS for commercial CD and ED. However, the widespread use of 2,4 - dinitrodiazobenzene perchlorate is hampered by two significant drawbacks: hygroscopicity, the technical product is overpressed.

2. Oxidiazo compounds

Many oxydiazophenols exhibit explosive properties. The greatest practical value as an IVS in the series of diazophenols is 2-diazo - 4,6 - dinitrophenol, C 6 H 2 N 4 O 5 , (diazodinitrophenol, DDNP, DDNP ) . Molecular weight 210.1, oxygen balance -60.9%.

Diazodinitrophenol is not hygroscopic, slightly soluble in water, soluble in methanol and ethanol, readily soluble in acetone, nitroglycerin, nitrobenzene, aniline, pyridine and acetic acid. It gets dark in the sunlight. Density of DDNP  mnc. = 1.719 g/cm 3, heat of formation 321 kJ/mol.

In the literature, both open and cyclic structures of the diazophenol fragment have been proposed for DDNP.

According to quantum chemical calculations, the most probable open structure for this compound in the gas phase is:

The brisance of DDNP is ~95% of the brisance of TNT, the high explosiveness in the lead block is 326 cm 3 /10 g. The flash point of diazodinitrophenol tfsp, 5 sec = 175-180 o C; the minimum charge for tetryl is 0.13 g, that is, less than that of fulminate of mercury. DDNP is less sensitive to shock than lead azide. The detonation speed of DDNF is 4400 m/s at a charge density of 0.9 g/cm 3 , 6600 m/s at a charge density of 1.5 g/cm 3 , 6900 m/s at a charge density of 1.6 g/cm 3 . The explosive decomposition of DDNP is described by the following equation:

C 6 H 2 N 4 O 5 à 42 CO + 2.52 CO 2 + 2.94 H 2 O +

3.15 H 2 + 7.67 C +7.87 HCN + 16.1 N 2

Diazodinitrophenol is obtained by diazotizing picramic acid with sodium nitrite in 10% sulfuric acid according to the scheme:

The target product precipitates from the reaction mass in the form of a red-brown precipitate. The disadvantage of the DDNP synthesis method is the presence of a large amount of toxic wastewater. The raw material base of DDNP is quite wide, since the starting substance, picramic acid, which is synthesized by partial reduction of picric acid with sodium sulfide, is a commercial product (it is used in the synthesis of a number of dyes).

DDNP as an IVS has the following disadvantages: it is overpressed, it does not have high enough heat resistance, the compound quickly darkens in sunlight, and it also stimulates the immune response, which contributes to the development of allergic syndrome.

Diazodinitrophenol has found use as an explosive in industrial initiation agents in the USA and China, as well as as a component of low-toxic percussion compositions of igniter caps for small arms, including sporting and hunting ones in Europe and North America

. Azids

Silver azide , AgN 3 - mol. weight 149.9. Initiating explosive. It darkens when exposed to light. Insoluble in water and organic solvents. Non-hygroscopic. Soluble in aqueous ammonia and hydrogen fluoride. Crystallizes from aqueous ammonia. Destroyed by nitric acid. The crystal density of silver azide is 5.1 g/cm 3 . The energy of the crystal lattice is 857.69 kJ/mol. The enthalpy of formation (DH f o) is + 279.5 kJ/mol, according to other data +311 kJ/mol. The detonation speed at maximum density is 4.4 km/s. The volume of gases during detonation is 244 l/kg. The explosiveness is 115 cm 3 /10 g. Silver azide is sensitive to impact and friction. The product is not overpressed. In terms of initiating ability, silver azide is noticeably superior to lead azide. The detonation speed of silver azide is 3830 m/s at a density of 2.0 g/cm 3 . The change in the rate of detonation of silver azide with increasing charge density is described by the equation:

D r = D 0 + 770 (r - r 0) m/s, where r 0 = 2 g/cm 2.

The detonation pressure of silver azide depends on the charge density:

P = (40r - 61) . 10 2 MPa

The softening temperature of silver azide is 250 0 C. Silver azide completely melts at 300 0 C (with decomposition). Rapid heating to 300 0 C causes an explosion of silver azide. The disadvantage of silver azide is its poor compatibility with antimony sulfide (Sb 2 S 3) and tetrazene, which are included in most injection formulations. Silver azide is prepared by mixing solutions of sodium azide and water-soluble silver salts. In a number of countries (Great Britain, Sweden) silver azide is produced in small quantities by the reaction

AgNO 3 + NaN 3 AgN 3 + NaNO 3

At the Department of ChTOSA LTI named after Lensoveta (SPbSTI (TU)), an alternative technology for producing bulk silver azide was developed by the reaction:

3 + N 2 H 4 + NaNO 2  AgN 3 + NaNO 3 + 2H 2 O

Silver azide is used to a limited extent as an explosive in small-sized initiation devices, where lead azide is not effective, and in heat-resistant blasting caps. As the dimensions of the initiating charge of the primer increase, the picture changes: silver azide becomes less effective compared to lead azide IVV, since its detonation speed is significantly lower. The practical use of silver azide is hampered by its high sensitivity to friction, the difficulty of obtaining it in bulk form, and its high cost.

Cadmium azide , Cd(N 3) 2 mol. mass 196.46 - white crystalline substance that initiates explosives. Dissolves and hydrolyzes with water. Hygroscopic. The density of single crystals is 3.24 g/cm 3 . The heat of explosion, according to various estimates, is in the range of 2336-2616 kJ/kg, T pl. = 291 0 C (with decomposition), T aux. (5 s) = 360 0 C. The detonation speed of cadmium azide is 3760 m/s at a density of 2.0 g/cm 3 . The change in the detonation speed of lead azide with increasing charge density is described by the equation:

D r = D 0 + 360 (r - r 0) m/s, where r 0 = 2 g/cm 2.

The detonation pressure of lead azide depends on the charge density:

P = (59r - 106).10 2 MPa

Cadmium azide is sensitive to impact and friction. The initiating ability of cadmium azide is greater than that of lead azide. Cadmium azide is obtained by reacting cadmium hydroxide or carbonate with excess HN 3 .

Cd(OH) 2 + 2 HN 3 à Cd(N 3) 2 + 2 H 2 O 3 + 2 HN 3 à Cd(N 3) 2 + CO 2 + H 2 O

Thallium azide , TlN 3, mol. weight 246.41 - yellow crystalline powder. Initiating explosive. Poorly soluble in water and organic solvents. The energy of the crystal lattice is 685.1 kJ/mol, enthalpy of formation (DH f o) = 234 kJ/mol, Tm = 334 0 C, Tvsp. (1 s) = 500 0 C. Thallium azide is less sensitive to impact and friction than lead azide. The initiating ability of thallium azide is noticeably less than that of lead azide. Toxic. Poorly compatible with nitro compounds. A convenient laboratory method for preparing thallium azide is the reaction of aqueous solutions of thallium perchlorate and sodium azide.

TlClO 4 + NaN 3 à TlN 3 + NaClO 4

Thallium azide is poisonous. Thallium azide is not used in industry as an IVS. Finds limited use in scientific research.

. Organic peroxides

Acetone peroxide (acetone diperoxide, 1,1,4,4 - tetramethyl - 2,3,5,6 - tetraoxacyclohexane) , (C 3 H 6 O 2) 2 - mol. mass 148, white crystalline initiating explosive. Acetone diperoxide is highly soluble in organic solvents: benzene, acetone, chloroform, diethyl ether, petroleum ether. Density = 1.33 g/cm3, T pl. = 132 - 133 0 C, T aux. (5 s) about 180 0 C. Very volatile substance. The vapor pressure of acetone diperoxide is 17.7 Pa at 25 0 C. Acetone diperoxide is less sensitive to shock than lead azide.

Its initiating ability is greater than that of mercury fulminate, but less than that of lead azide. According to other data, a charge of 0.5 g of acetone diperoxide pressed into a sleeve from CD No. 8 under a pressure of 30 MPa did not initiate a charge of hexogen.

Acetone diperoxide is obtained by reacting acetone with Caro acid (a solution of hydrogen peroxide in concentrated sulfuric acid) in acetic anhydride.

Tricycloacetone peroxide (cyclotriacetone peroxide, 1,1,4,4,7,7-hexamethyl-2,3,5,6.8.9-hexaoxacyclononane) , C 9 H 18 O 6, mol. mass 222.1 - initiating explosive.

(CH 3) 2 C - O - O - C (CH 3) 2

Cyclotriacetone peroxide forms colorless crystals in the form of prisms. Monocrystal density is 1.272 g/cm 3 (X-ray), soluble in benzene, acetone, chloroform, ether, petroleum ether, pyridine, glacial acetic and nitric acids. It dissolves in ethyl alcohol when heated, but does not dissolve in water and aqueous solutions of ammonia. Forms at least six polymorphic forms. Hydrolyzes with dilute acids. T pl. is 97 0 C. The energy of formation of cyclotriacetone peroxide is 90.8 kJ/mol. Oxygen balance -151.3%. The heat of explosion is 5668 kJ/kg. High explosiveness 250 cm 3 /10 g. Detonation speed at a density of 0.92 g/cm 3 3750 m/s, at a density of 1.18 g/cm 3 - 5300 m/s, high explosiveness in a lead block 250 cm 3 /10 g. Cyclotriacetone peroxide does not corrode copper, aluminum, zinc, tin, iron; Lead corrodes. The shock sensitivity of cyclotriacetone peroxide is higher than that of lead azide; in terms of initiating ability, cyclotriacetone peroxide is inferior to lead azide: its minimum charge for hexogen is 0.1 g (press pressure 30 MPa) and 0.16 g for TNT.

The product is obtained from acetone acidified with sulfuric acid, which is treated with perhydrol (a dilute solution of hydrogen peroxide).

Cyclotriacetone peroxide is a kinetic product of acetone oxidation, and acetone diperoxide is a thermodynamic product, that is, during storage, the trimer can turn into a dimer. Acetone peroxides have no practical significance as explosives due to their high volatility and tendency to sublimation.

5. Acetyleneides

In a neutral or slightly acidic environment, a mixed salt is formed Ag 2 C 2 . AgNO 3 - initiating explosive, molecular weight 409.7, density 5.369 g/cm 3 (X-ray), decomposition temperature about 220 0 C, high explosiveness in a lead block 136 cm 3 /10 g, heat of explosion 1888 kJ/kg. The detonation speed is 2250 m/s at a density of 2.51 g/cm 3 and 4540 m/s at a density of 3.19 g/cm 3 . The initiating ability is greater than that of mercury fulminate and depends on the method of obtaining the double salt. Minimum charge Ag 2 C 2 . AgNO 3 equal to 0.005 g for PETN, 0.07 g for tetryl and 0.25 g for TNT. The salt is not overpressed. In practice, it is not used as a TRS.

. Dinitrobenzfuroxan salts

(CDNBF) is a low-toxic “pseudo-initiator” substance.

6 - Potassium dinitro-7-hydroxy-7-hydrobenzfuroxanide

The melting point of the potassium derivative is 174 0 C, the flash point with a 5-second delay of CDNBF is 207 - 210 0 C, the temperature of the beginning of intensive decomposition is about 190 0 C. The density of the single crystal is 2.21 g/cm 3 . The sensitivity to friction of KDNBF is the same as that of TNRS. In terms of shock sensitivity, the adduct (Meisenheimer s-complex) is superior to lead azide, but inferior to mercury fulminate.

CDNBF can be obtained from o-nitroaniline according to the following scheme:

KDNBP is used in low-toxicity ignition pyrotechnic compositions instead of TNPC together with the non-toxic oxidizer KNO 3 and additives that increase the susceptibility of the compositions to impact and friction. Pilot production of the KDNBF product began in the United States shortly after World War II. A significant disadvantage of the KDNBP compound is its insufficiently high heat resistance.

At the beginning of the 21st century, it was obtained and studied as a possible low-toxic substitute for TNRS potassium salt 4,6-dinitro-7-hydroxybenzofuroxan (KDNGBF),

Potassium salt of 4,6-dinitro-7-hydroxybenzofuroxan

Unlike the KDNBF connection , which is the Meisenheimer complex, the substance KDNHBP is a simple salt.

Potassium salt exists in monohydrate and anhydrous form. The density of CDNGBF lies in the range of 1.94 - 2.13 g/cm 3 . The temperature at which the intensive decomposition of KDNGBF salt begins is about 270 0 C, the substance retains its operational properties after heating at 120 0 C for 90 days. The substance KDNGBF is a fast-burning compound with good heat resistance and is quite safe to handle.

CDNGBF is obtained from available meta-bromoanisole according to the following scheme:

At the final stage of the reaction, the azide ion replaces bromine, and the methoxy group is replaced by hydroxyl.

Since the beginning of 2009, in the USA, KDNGBF salt has been approved for use in low-toxic pyrotechnic compositions for initiation agents.

7. Coordination metal complexes with an outer sphere

Increased requirements for technological, operational and environmental safety of initiating explosives have led researchers to search for energy-intensive compounds in the series d-metal complex salts .

In the USA, it was proposed to use as an explosive for a safe means of initiation. pentaammine (5-cyano-2H-tetrazolato-N 2) cobalt(III) perchlorate (CP)

Pentaammine (5-cyano-2H-tetrazolato-N 2) cobalt(III) perchlorate, CP

The density of single crystals of the SR complex is 1.97 g/cm 3, the temperature at which intensive decomposition begins (at a heating rate of 20 o C/min) is 288 0 C. The SR sample, after being kept for three years at 80 0 C, retained all its operational properties . The area of ​​transition from combustion to detonation (with a charge diameter of 5 mm) is approximately 4.5 mm, the time of transition from combustion to detonation is about 75 μs, the detonation speed is 7.18 km/s at a density of 1.75 g/cm 3 . The dependence of the SR detonation speed on the charge density is described by the following equation:

D = 0.868 + 3.608r,

where D is detonation speed (km/s),

r is the initial charge density of the SR (g/cm 3).

All measurements were carried out for a charge diameter of 6.35 mm.

The shock sensitivity of the SR complex is less than that of the heating element. The metal complex is poorly compatible with standard HMX. CP is slightly hygroscopic.

The technological process for producing CP, developed by Unidinamic (USA), consists of a number of stages.

First, carboxypentaammine cobalt (III) nitrate (CPCN) is obtained by the reaction:

2 Co(NO 3) 2 + NH 3 (H 2 O) + 2 (NH 4) 2 CO 3 + 1/2O 2 à

à 2 NO 3 + 2 NH 4 NO 3 + H 2 O

The process for synthesizing the CPCN complex involves bubbling air through a stirred paste of ammonium carbonate and cobalt nitrate in an ammonia solution for 96 hours to oxidize Co 2+ to Co 3+ . After aeration is completed, the bright red reaction mass is heated to 70 -75 0 C to dissolve the CPCN salt, filtered from impurities and cooled to 0 0 C. The precipitated product is washed with alcohol and dried.

The resulting substance does not have explosive properties.

To obtain aquapentaammine cobalt (III) perchlorate (APCP), the CPCN complex is treated with a large excess of perchloric acid.

NO 3 + 3 HClO 4 à (ClO 4) 3 + CO 2 + HNO 3

The process takes place in two stages.

The raw CP complex is purified from an ammonium perchlorate solution acidified with perchloric acid. Purification removes the bulk of the “amide complex” and virtually all unreacted cyanotetrazole, as well as residual nitric acid. The desired fractional composition of CP is obtained by adding a hot aqueous solution of purified CP to cooled 2-propanol. After filtration, the product is sifted and dried at 60 - 65 0 C for several hours. During one deposition, about 1 kg of commercial CP is obtained, suitable for equipping initiation means.

This reaction is key in the entire process of CP synthesis.

The SR substance has been proposed for use in electric detonators. However, the complex is toxic, which prevents its widespread use.

Perchlorate cobalt(III) pentaammine (5-nitrotetrazolato-N2) (NCP, NKT) has found limited use in Russia as an explosive for safe initiation means. The tubing substance, compared to traditional IVVs, has a reduced sensitivity to static electricity discharges. The density of single crystals of the NKT complex is 2.03 g/cm 3, the temperature of the beginning of intensive decomposition is 265 0 C (TG/DTA). Thermostating in sealed conditions at 200°C for 6 hours does not lead to a change in its properties. The area of ​​transition from combustion to detonation at the tubing with a diameter of 6.25 mm at r = 1.60-1.63 g/cm 3 is about 4.5 mm. The detonation speed of the tubing substance is 6.65 km/s with a density of 1.61 g/cm 3 . The minimum charge of hexogen in the sleeve from CD No. 8 is 0.15-0.20 g. The shock sensitivity of the tubing complex is less than the sensitivity of the heating element. The product is non-hygroscopic. The NKT compound is less toxic than the CP complex.

Pentaammine (5-nitrotetrazolato-N 2) cobalt(III) perchlorate, tubing

The technological process for producing tubing is similar to the technological process for preparing CP. The target complex is synthesized from the complex salt of APCP and the sodium salt of 5-nitrotetrazole in an aqueous perchloric acid solution at 95 - 100 0 C for three hours. The process of cleaning the tubing complex from impurities is not fundamentally different from the method of preparing commercial CP.

It is considered as one of the most promising explosives for safe initiation means, including laser ones. tetraammine-cis-bis(5-nitro-2H-tetrazolato-N 2) cobalt(III) perchlorate (BNCP):

Cobalt(III) tetraammine-cis-bis (5-nitro-2H-tetrazolato-N 2) perchlorate (BNCP)

The density of a single crystal of BNCP is 2.05 g/cm 3 , detonation speed at a density of 1.79 g/cm 3 is equal to 7117 m/s, the temperature of the beginning of intensive decomposition (at a heating rate of 20 o C / min.) is 269 o C (DSC). The minimum charge of hexogen in the cartridge case from CD No. 8 is 0.05 g, the time of transition from combustion to detonation is about 10 μs. The shock sensitivity of the BNCP complex is greater than that of the CP substance, but less than that of PETN. The BNCP substance is obtained by the reaction:

The reaction takes place at a temperature of about 90°C and a holding time of about 3 hours. In the synthesis of BNCP, the starting cobalt tetraamminate was used in the form of ClO 4 perchlorate or NO 3 nitrate, the synthesis and properties of which are described in detail in the literature. The sodium salt of 5-nitrotetrazole was obtained either by the Sandmeyer reaction in the presence of copper salts (see section 6.2), or as a result of the following non-catalytic process:

The reaction is carried out in two stages. At the first stage, 5-aminotetrazole is diazotized with an excess of sodium nitrite in sulfuric acid. At the second stage, the reaction mass is neutralized with sodium carbonate, water is distilled off and the target product is extracted with acetone from the mixture of salts. Sodium nitroterazolate is isolated as a crystalline hydrate, which is less hazardous to handle than the anhydrous salt.

The yield of the BNCP complex was 50-60%, based on complex cobalt carbonate. The BNCP complex has found application in pyroautomatic systems of missile systems in the United States as part of semiconductor and optical detonators.

Complex perchlorates of cobalt (III) ammates with tetrazole ligands are heat-resistant, non-hygroscopic, and safer than standard IVS. These substances do not contain highly toxic heavy metals: mercury, lead, cadmium. The complex cation of ammine cobalt (III) is low toxic. But these cobalt complexes contain the biologically dangerous perchlorate anion, which is probably a teratogen (causes deformities during the intrauterine development of a child) and acts on the thyroid gland. Therefore, complex cobalt(III) amminate perchlorates with azole ligands cannot be classified as “green” initiating substances.

Meanwhile, the search for low-toxic, energy-rich substances for initiation agents led researchers from the Los Alamos National Laboratory (USA) at the beginning of the 21st century to the production of copper and iron complex salts of 5-nitrotetrazole, presented as ideal “green” initiators. The complexes have the following gross formula:

(Cat) 1-4 [M II (NT) 3-6 (H 2 O) 3-0 ],

where Cat= NH 4, Na, M = Fe, Cu

The authors of the study claim that the performance properties of these metal complexes can be easily controlled by the nature of Cat and M, as well as the content NT - in a molecule. It was found that the complexes

Na 2 and Na 2

are safer IVS than AS and TNRS. Some characteristics of complex nitrotetrazolates FeII And Cu II are given in the table.

Properties of metal complex nitrotetrazolates Fe II and Cu II

At high pressures, the complexes are overpressed. Tests showed that the experimental CDs and EDs containing initiating charges of the Na 2 complex or Na 2 salt did not differ in their characteristics from the standard ones loaded with lead azide. Industrial production of these metal complexes does not currently exist, apparently.

The fact that nickel hydrazinates with oxidizing anions have a short transition from combustion to detonation and can be used to initiate organic energy-saturated substances has been known for about a hundred years. However, these compounds are inferior in efficiency to lead azide, so until recently the possibility of their practical use in CD and ED was not considered. The search for environmentally friendly, energy-rich compounds that do not harm the environment has forced researchers to return to this class of metal complex salts. One of the promising “green” energy-rich compounds that can replace lead azide in industrial CD and ED is complex hydrazinnickel(II) nitrate Ni(N 2 H 4) 3 (NO 3) 2 . The density of the complex single crystal is 2.129 g/cm 3 . The density of the pressed charge of the Ni(N 2 H 4) 3 (NO 3) 2 complex is 1.55 g/cm 3 (at a pressing pressure of 20 - 40 MPa) and about 1.70 g/cm 3 (at a pressing pressure of 60 - 80 MPa). Charges of complex nickel nitrate are repressed at pressures above 60 MPa. The flash point of complex nickel hydrazinate with a 5-second delay is 167 0 C. The onset temperature of decomposition and the onset temperature of intensive decomposition, determined by differential thermal analysis (DTA), are 210 0 C and 220 0 C, respectively. The activation energy for the thermal decomposition of complex nickel nitrate is 78 kJ/mol (based on the results of TG/DTA analysis) and 89 kJ/mol (based on the flash temperature). The detonation speed of the metal complex is 7.0 km/s at a charge density of 1.7 g/cm 3 . The minimum charge of Ni(N 2 H 4) 3 (NO 3) 2 in the sleeve from CD No. 8 according to the heating element is 0.15 g. Complex nickel nitrate is obtained from available raw materials, in standard equipment in an aqueous environment at a temperature of 65 0 C according to the equation :

Ni(NO 3) 2 *6H 2 O + 3N 2 H 4 *H 2 O à Ni(N 2 H 4) 3 (NO 3) 2 + 9H 2 O

Hydrazinnickel(II) nitrate

Complex nitrate Ni(N 2 H 4) 3 (NO 3) 2 (pink substance) is not hygroscopic and practically insoluble in water; it is compatible with construction materials. The metal complex is resistant to sunlight and X-ray radiation, and is insensitive to charges of static electricity. An industrial technology for producing complex nickel hydrazinate has been developed in China. Complex nickel nitrate Ni(N 2 H 4) 3 (NO 3) 2 is used in China in environmentally friendly industrial CD and ED.

Complex hydrazinnickel(II) azide (N 3) 2 is another candidate for replacing lead azide in “green” industrial CD and ED. The density of the complex single crystal is 2.12 g/cm 3 . The flash point of complex nickel azide after a 5-second delay is about 193 0 C. The onset temperature of decomposition is 186 0 C (DTA). The product decomposes in two macrokinetic stages. The activation energy of the first stage of thermal decomposition is 142.6 kJ/mol, the second stage is 109.2 kJ/mol. The detonation speed of the metal complex is 5.42 km/s at a charge density of 1.497 g/cm 3 . The minimum charge (N 3) 2 in the sleeve from CD No. 8 for hexogen is 0.045 g. The shock sensitivity of the nickel azide complex is less than the sensitivity of the heating element. Complex azide is prepared from nickel nitrate or acetate, hydrazine hydrate and sodium azide according to the equation:

Ni(NO 3) 2 *6H 2 O + 2N 2 H 4 *H 2 O + 2NaN 3 à (N 3) 2 + 8H 2 O + 2NaNO 3

Hydrazinnickel(II) azide

Ni(CH 3 COO) 2 *4H 2 O+2N 2 H 4 *H 2 O+2NaN 3 à (N 3) 2 +6H 2 O+2CH 3 COONa

Hydrazinnickel(II) azide

Complex nickel azide is a green polycrystalline product. The technical product is not hygroscopic and insoluble in water. In China, a pilot-industrial technology for the production of complex nickel azide has been developed, which makes it possible to safely obtain up to 5 kg of product in one deposition. Testing of EDs containing hydrazinnickel (II) azide as a primary charge , have shown that they are not inferior in reliability to standard EDs and can be used in the mining industry.

Conclusion

There are many IVS that do not contain lead and mercury, but nowadays they are not so widely used (they cannot be standard) due to various shortcomings. But in some cases they have more advantages, and their use is the most profitable and appropriate. In conclusion, it should be said that all over the world they are striving to find low-toxic energy-rich substances.

For example, the CP substance has been proposed for use in electric detonators. However, the complex is toxic, which prevents its widespread use. The widespread use of 2,4 - dinitrodiazobenzene perchlorate is hampered by two significant disadvantages: hygroscopicity, the technical product is overpressed. DDNP as an IVS has the following disadvantages: it is overpressed, it does not have high enough heat resistance, the compound quickly darkens in sunlight, and it also stimulates the immune response, which contributes to the development of allergic syndrome.

List of used literature

1. Ilyushin M.A. Energy-saturated substances for initiation means: textbook / M.A. Ilyushin, I.V. Tselinsky, A.A. Kotomin, Yu.N. Danilov - St. Petersburg: SPbGTI (TU) - 2013 -177 p.

Ilyushin M.A. Metal complexes in high-energy compositions (monograph) / ed. I.V. Tselinsky/ M.A. Ilyushin, A.M. Sudarikov, I.V. Tselinsky and others - St. Petersburg: Leningrad State University named after A.S. Pushkina, 2010. - 188 p.

3. Loskutova L.A. Sensitivity of energetic materials to detonation pulse: guidelines / L.A. Loskutova, M.A. Ilyushin, A.V. Smirnov, I.V. Bachurina - St. Petersburg: SPbGTI (TU), 2011. - 23p.

Loskutova L.A. Flash point of condensed energy-intensive substances: guidelines / L.A. Loskutova, A.S. Kozlov, M.A. Ilyushin, I.V. Bachurina - St. Petersburg: SPbGTI (TU), 2007. - 20 p.

Loskutova L.A. Sensitivity of solid explosive systems to mechanical influences: guidelines / L.A. Loskutova, A.S. Kozlov - St. Petersburg: SPbGI (TU), 2007 - 22 p.