RU2471759C2 - Explosive composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to explosives for charging explosive devices for various purposes and can be used in mining industry, construction and other science and engineering fields associated with use of explosive energy of powerful explosives. The explosive composition contains a powdered combustible metal, a plasticiser, a polyacrylic polymer, diphenylamine and an oxidant - ammonium perchlorate. The blasting explosive used is triaminobtrinitrobenzene with crystal specific area of not more than 2500 cm²/g in amount of 19-21 wt % of the total weight of the composition.

EFFECT: preparation of an explosive composition with high explosion safety owing to low sensitivity of the explosive composition to mechanical and thermal action and providing full chemical explosive conversion of the explosive during standard application.

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Description

The invention relates to explosives (explosives) for equipping explosive devices for various purposes and can be used in mining, geology, construction and other fields of science and technology related to the use of explosive energy of powerful explosives.

When carrying out such work, increased demands are made on the explosion safety of explosive compositions.

Known relatively explosive explosive composition (AC), protected by the patent of the Russian Federation No. 2071957, C06B 25/04, publ. 01/20/1997, the Composition contains a traditional blasting explosive (trotyl) and a plasticizer in the form of trinitroethyl ester of trinitromobutyric acid.

The disadvantage of this aircraft is that the composition has a relatively low blast power, has limited use and is intended mainly for use in shaped linear charges and other cumulative structures.

More powerful and with wide application possibilities is plastisol aircraft, described in the patent of the Russian Federation No. 2235967, C06B 25/34, publ. September 10, 2004. Plastisol BC according to this patent is characterized by the presence of a liquid plasticizer, a polymer of a polyacrylic series, a blasting explosive and a powdery combustible metal. RDX or HMX are used as blasting explosives.

The disadvantage of this composition is its high explosiveness.

Also known is an explosive composition containing a blasting explosive (RDX or HMX), aluminum powder, liquid plasticizer, a polymer of the polyacrylic series and diphenylamine, described in the patent of the Russian Federation No. 2315742, С 25В 25/00, publ. 01/27/2008 In order to increase safety, phlegmatized RDX or HMX is used as a blasting explosive.

The closest and selected as a prototype is the technical solution described in the patent of the Russian Federation No. 2415831, IPC ⁷ С06В 25/00, publ. 02/10/2011, under the name "Explosive composition of multifunctional action." The explosive composition includes a blasting explosive, a powder combustible metal, a plasticizer, a polyacrylic polymer, diphenylamine and an oxidizing agent, ammonium perchlorate.

The disadvantage of these aircraft is the relatively low explosion safety under external emergency and damaging effects. Low explosion safety is due to the use of highly sensitive blasting explosives RDX or HMX (albeit phlegmatized) as the main component. A composition based on these components easily explodes both in the form of parts and in the composition of products.

The objective of the present invention is the creation of aircraft with high explosion safety during official handling, emergency and damaging effects and high explosion power.

The technical result consists in lowering the sensitivity of the aircraft to mechanical and thermal influences while ensuring the completeness of the chemical explosive transformation of the aircraft with regular use due to a qualitative change in the component content of the aircraft.

To achieve the specified technical result in an explosive composition including a blasting explosive, a powder combustible metal, a plasticizer, a polyacrylic polymer, diphenylamine and an oxidizing agent - ammonium perchlorate, according to the invention, triaminotrinitrobenzene with a specific crystal surface of not more than 2500 cm ^{2 was used} / g with a share of 19-21 wt.% of the total weight of the composition.

In essence, the differences between the claimed explosive composition and the prototype consist in replacing the explosive of hexogen or octogen with the blasting explosive of triaminotrinitrobenzene (19-21 wt.%) And imposing a limitation on the dispersion of the blasting explosive of triaminotrinitrobenzene, expressed as the specific surface of its crystals (not more than 2500 cm ² / g). The remaining components remain the same (including in quantitative terms) and perform the same functions as in the prototype.

The presence in the claimed invention features that distinguish it from the prototype, allows us to consider it appropriate to the condition of "novelty."

In the search process, no technical solutions were found containing a set of features similar to the set of distinctive features of the claimed composition, which allows us to conclude that its criterion is “inventive step”.

Triaminotrinitrobenzene (TATB) is a low-sensitive blasting explosive.

Table 1 shows the data of the explosive technology of the TATB for sensitivity to mechanical stress (shock and friction), as well as flash point and chemical resistance.

Table 1 Shock sensitivity Sensitivity to friction, kgf / cm Flash point, ° С Chemical resistance [NO ₂ ],% Lower limit mm The frequency of explosions,% With sand Without sand > 300 0 1300-1500 > 3000 388 <0.0001-0.0002

Sensitivity to shock was determined according to GOST 4545-80. Parameters defined:

- the lower limit (the maximum height of dropping cargo weighing 10 kg per equipped roller device No. 2, in which in a series of 25 tests not a single explosion occurs);

- frequency of explosions (the number of explosions as a percentage in a series of 25 tests when dropping a load of 10 kg from a height of 250 mm onto an equipped roller device No. 1).

Sensitivity to friction was studied on the I-6-2 device. The lower limit was determined - the maximum force of the preload of the rotating punch, in which in 10 parallel experiments not a single explosion was recorded. In tests, explosive hinges with and without sand were used.

Flash point was determined at a delay time of 30 s.

Chemical resistance was studied by the FEC method (the number of nitrite ions released during exposure to a sample of explosives at a temperature of 110 ° C for 8 hours).

Since TATB is the main explosive component of the proposed aircraft, its use radically reduces the sensitivity of the aircraft as a whole. However, this technical result is achieved only with a specific surface area of TATB crystals of not more than 2500 cm ² / g. With a larger specific surface (greater dispersion), the plastic properties of the composition significantly decrease. As a result, at the stages of operation of the products due to vibrational loads, shock, drops, atmospheric influences (high temperature, low humidity), cracking of the aircraft occurs with the formation of a network of multiple microcracks extending deep into the aircraft array. In emergency situations associated, for example, with a fire or shock-wave action, there is a threat of convective (explosive) combustion of the aircraft with a transition to detonation. When the claimed specific surface area of the TATB crystals is not more than 2500 cm ² / g, the combustion of the aircraft after ignition proceeds in a calm layer-by-layer mode without transition to an explosion.

BB TATB has a negative oxygen balance. Ammonium perchlorate is a powerful oxidizing agent. Its use in the inventive BC improves the oxygen balance, ensures the completeness of the chemical reaction of the oxidation of combustible components of the composition and high energy characteristics of the explosion. Other oxidizing agents may be used, for example, potassium perchlorate or barium nitrate.

A plasticizer (for example, LD-70) and a polymer of a polyacrylic series (for example, Vitan) form a gelatinous plastisol bond (gel), which prevents embrittlement of the aircraft.

The chemical stability stabilizer diphenylamine (DFA) provides heat resistance to the composition.

Powder combustible metal (for example, aluminum, magnesium, their alloys) increases the thermal component, increasing the explosive effect of the explosion.

The applicant conducted extensive experimental studies on the development of the inventive aircraft with varying its components.

Table 2, as an example of practical implementation, shows the specific content of one of the compositional options, ensuring its best explosive characteristics (table 3) and high explosion safety indicators (table 4).

table 2 Components Content, wt.% Triaminotrinitrobenzene (TATB) with a specific crystal surface of 2500 cm ² / g twenty Aluminum powder 27 Plasticizer (LD-70) fifteen Polyacrylic Series Polymer (Vitan) 3,5 Ammonium Perchlorate (Anositol) 34.5 Diphenylamine (DFA) 0.6 (in excess of 100%)

Table 3 Explosive characteristics Values Knock speed, m / s 6100-6200 TNT equivalent 1.73-2.02 High explosiveness, m 0.44-0.60 Throwing ability (copper case Δ = 6 mm), m / s 2000-2100 Shock wave sensitivity, kbar 94-110 Flash point, ° С 240 Thermal explosion temperature, ° С 270-312

Table 4 Emergency and damaging effects Result The impact of small arms bullets caliber 5.45-12.7 mm at a speed of up to 900 m / s The absence of any signs of explosive transformation Impact of steel fragments with a speed of up to 2000 m / s Drop from a height of 12 m onto a reinforced concrete base Flooding into water to a depth of 6000 m The introduction of a steel rod at a speed of 40 m / s Exposure to the heat field of a fire with a volume average temperature of 800 ° C Complete burnout without explosive conversion

The manufacturing process of the inventive aircraft includes the preparation of components, their mixing, pouring the resulting plastic mass into a mold (mold) and subsequent curing. The preparation of the plastic mass and its curing occur at room temperature without decomposition and take little time.

Experimental studies have shown that the optimal percentage of explosives TATB in the inventive composition, providing the required detonation ability and the highest explosive power at high explosion safety, is 19 ÷ 21 wt.%. The output of the TATB content from the range of 19 ÷ 21 wt.% Leads to the deterioration of the complex energy of the explosion:

- when <19 wt.% significantly reduces the blasting effect,

- at> 21 wt.%, the high-explosive effect and throwing ability decrease. In the range of 19 ÷ 21 wt.% The best balance of blasting and high explosive damaging effects of the explosion of the inventive aircraft in combination with high safety indicators is achieved. In this case, the specific surface area of BB TATB crystals is not more than 2500 cm ² / g.

The use of a low-sensitivity explosive agent TATB with a specific crystal surface of not more than 2500 cm ² / g and an oxidizing agent of perchlorate type made it possible to create a high-power plastisol aircraft with a wide range of characteristics of the damaging effect, resistant to external accident and damaging effects.

Distinctive features in the stable interconnection of the totality of essential features have made it possible to increase safety in official handling, as well as in case of emergency and damaging effects that may occur during storage and operation of products equipped with this composition.

The above information about the claimed composition, described in the formula, indicate the possibility of its implementation using known means and methods.

Thus, the claimed technical solution meets the criterion of "industrial applicability".

Claims (1)

An explosive composition including a blasting explosive, a powder combustible metal, a plasticizer, a polyacrylic polymer, diphenylamine and an oxidizing agent - ammonium perchlorate, characterized in that triaminotrinitrobenzene with a specific crystal surface of not more than 2500 cm ² / g and with a fraction of 19-21 wt.% Of the total weight of the composition.