RU2756081C1 - Thermoplastic explosive composition and method for production thereof - Google Patents

Abstract

FIELD: explosives.SUBSTANCE: group of inventions relates to the field of technology for production of mixed thermoplastic explosive materials. The thermoplastic explosive composition contains diaminodinitroethylene, 3,4-bis-(4-nitrofurazan-3-yl)-furazan as explosive components and polybutyl methacrylate as an inert additive, at the following ratio of ingredients, wt.%: diaminodinitroethylene - 87 to 93 together with 3,4-bis-(4-nitrofurazan-3-yl)-furazan - 4 to 10, polybutyl methacrylate - the rest. The components of the composition are prepared. The components are mixed using a mixing apparatus. Input control of the powdered components of the mixed explosive composition for compliance of the physical and chemical characteristics of the explosive components with nominal values, namely, the melting point, the mass fraction of acetone-insoluble substances, moisture, volatile substances, the pH of the aqueous extract, is conducted initially. A suspension of the polymer inert component of the mixed explosive composition is taken in the form of polybutyl methacrylate; dissolved in an organic solvent - acetone, at a ratio of 1:5 to 1:7 wt. pts.; sustained until complete swelling to a gel state. The gel-like base of the inert component is introduced into a solution of the energy component of the mixed explosive composition - 3,4-bis-(4-nitrofurazan-3-yl)-furazan in acetone at a ratio of 1:3 to 1:5 wt. pts.; mixed in a mixer to homogeneity. A second powdered energy component - -insoluble diaminodinitroethylene - is introduced into the resulting homogeneous mixture of components. The mixture is mixed while heating until visually observed removal of the visible excess of the solvent – acetone. The mixture is sustained in an exhaust hood and mixed periodically to remove the solvent and eliminate caking. The mixture is dried until complete evaporation of the solvent - acetone - in a muffle furnace at a temperature of no more than 60°C, which is controlled by the weight method. The prepared composition is sent to the stage of pressing in a mould at a pressure of no less than 50 MPa.EFFECT: reduction in the level of shock-wave sensitivity compared with the prototype is provided while maintaining high power indicators.2 cl, 2 dwg

Description

The proposed invention relates to the field of technologies for producing blended thermoplastic explosive materials characterized by low shock-wave sensitivity and high power characteristics.

The urgency of the problem being solved is based on the need to select the component composition and technology for obtaining such a mixed thermoplastic explosive (HE), which would have a low shock-wave sensitivity and high power characteristics. A feature of a mixed explosive composition based on a polymer binder is the need to introduce a certain amount of an organic solvent that is compatible with powdered energy components to ensure the required viscosity of the composition during the manufacturing process. in solution, the components are in a much more technologically acceptable state for their uniform distribution with each other. However, the state of the mixed explosive composition obtained for subsequent mechanical molding is not technologically acceptable, which dictates the need to remove the organic solvent from the explosive composition.

Known from the prior art (SU 01841262, IPC S06B 21/00, publ. 27.12.2016) is a powerful explosive composition based on RDX as an energy component of an explosive and a polymer binder in the form of a mixture of methyl acrylate with nitrile acrylic acid.

The disadvantages of the analogue include the fact that the relatively high power indicators of the energy component in the presence of an inert binder are reduced, which negatively affects the efficiency of the energy output of the finished material.

The task of the authors of the invention is to develop a component composition and technology for producing a mixed thermoplastic explosive composition with high power indicators and a low level of shock-wave sensitivity.

The technical result achieved with the use of the present invention consists in obtaining a mixed thermoplastic explosive composition with a lower level of shock-wave sensitivity than that achieved in the prototype, while maintaining high power indicators.

The claimed thermoplastic explosive composition, in contrast to the known one, comprising an explosive component and an inert additive, according to the invention contains diaminodinitroethylene, 3,4-bis- (4-nitrofurazan-3-yl) -furazan as explosive components, and as an inert additive - polybutyl methacrylate with the following ratio of ingredients, wt%, d .: diaminodinitroethylene - 87-93 wt. etc., together with 3,4-bis- (4-nitrofurazan-3-yl) -furazan - 4-10 wt. etc., polybutyl methacrylate - the rest.

Known from the prior art is a method for mixing components of an explosive composition (RF patent No. 2316527, IPC S06B 21/00, publ. 10.02.2008), which includes the preparation of liquid-viscous, powdery components, dosing them into the mixer and mixing. In the process of preparing liquid-viscous components, a high-molecular-weight polymer binder and a plasticizer are first mixed at a ratio of 30: 70-40: 60 at a temperature of 65-85 ° C for 40-60 hours, after which the rest of the plasticizer is loaded and stirred at a temperature of 60-75 ° C within 3-9 hours. The mixing process is carried out with the supply of an inert gas.

The disadvantage of this method is the lack of measures to ensure the technological state of the mixture of components of the aircraft, suitable for storage and subsequent molding into the target product.

The task of the authors of the invention is to develop a method for producing a mixed explosive composition characterized by a lower level of shock-wave sensitivity than that achieved in the prototype, while maintaining high power indicators and ensuring a technologically acceptable state of a mixture of components of a mixed explosive for subsequent mechanical molding into a target product.

The technical result achieved by using the proposed method is to ensure the production of a finished mixed thermoplastic explosive (HE) with a lower level of shock-wave sensitivity than that achieved in the prototype while maintaining high power indicators.

The specified task and the new technical result are provided by the fact that, in contrast to the known method of manufacturing a thermoplastic mixed explosive material, including the preparation of the components of the mixed explosive material, mixing the components, mixing the components using a mixing device, according to the invention, the input control of the powder components of the mixed explosive composition is initially carried out for compliance physicochemical characteristics of explosive components to nominal values, namely: melting temperature, mass fraction of substances insoluble in acetone, moisture, volatile substances, pH of the aqueous extract, then take a sample of the polymer inert component of the mixed explosive composition in the form of polybutyl methacrylate, dissolve in an organic solvent - acetone in a ratio of 1: 5-1: 7 parts by weight, then kept until complete swelling to the state of a gel, after which the gel-like base of the inert component is introduced into the solution of the energy component mixed explosive composition - 3,4-bis- (4-nitrofurazan-3-yl) -furazan in acetone in a ratio of 1: 3-1: 5, mixed in a mixer until a homogeneous state, after which a second powder is introduced into the resulting homogeneous mixture of components the energy component is diaminodinitroethylene, insoluble in acetone, the mixture is stirred by heating until the visually observed removal of the visible excess of the solvent - acetone, after which the mixture is kept in a fume hood, stirring periodically to remove the solvent and exclude clumping, then the mixture is dried until the solvent - acetone is completely evaporated into a muffle furnace at a temperature of no more than 60 ° C, which is controlled by the gravimetric method, after which the prepared composition is sent to the stage of pressing in a mold at a pressure of at least 50 MPa.

The proposed method for manufacturing a thermoplastic mixed explosive material and a thermoplastic explosive composition are explained as follows.

Initially, the incoming control of the powdery components of the mixed explosive composition is carried out for compliance with the physicochemical characteristics of the explosive components with the requirements of technical specifications. In the claimed method, the following are used as components of the mixed explosive composition:

- energetic substances - diaminodinitroethylene (aprol) - 87-93 wt. d., (3,4-bis- (4-nitrofurazan-3-yl) -furazan (BNTP) - 10-4 wt.

- as a binder - a polymer inert component in the form of polybutyl methacrylate (PBMA) - the rest. After mixing the main components, add as a dye - Sudan - not more than 0.1 wt.d. over 100 mass d. the main substance.

The choice of a polymer binder is based on the manifestation of its physicochemical properties (high thermal and chemical resistance, resistance to oxygen, elasticity, inertness to explosives, low softening temperature), which is critical for ensuring manufacturability during subsequent mechanical processing of the finished mixed explosive.

The choice of the components of the mixed thermoplastic explosive is dictated by the requirement to ensure a low level of shock-wave sensitivity while maintaining the power of the explosive composition in comparison with the prototype, which was confirmed by experimental studies.

The conditions of manufacture and the composition of the mixed thermoplastic explosive were experimentally selected, in which the power indicators corresponding to the known high-power explosives were achieved, and also provided a lower sensitivity to shock wave action than in the prototype.

Initially, the components of the mixed explosive material are prepared. For this, the powder components are monitored for compliance with the physicochemical indicators of these components to the nominal indicators (dispersity, solubility in an organic solvent of the main substance and the presence of impurities insoluble in acetone, pH of the aqueous extract).

After the incoming control of the physicochemical parameters of the powder components suitable for use under the conditions of the proposed manufacturing method to obtain the desired quality of the mixed thermoplastic explosive, these components are mixed. For this, the polymer inert component in the form of polybutyl methacrylate is dissolved in an organic solvent - acetone in a ratio of 1: 5-7 wt. hours, then stand until complete swelling to the state of a gel, after which the gel-like base of the inert component is introduced into the solution of the energy component of the mixed explosive composition - explosive BNTF in acetone in a ratio of 1: 3-1: 5 wt. hours, mix in a mixer until a homogeneous state, after which a second powdery energy component is introduced into the resulting homogeneous mixture of components - BB aprol, insoluble in acetone, the mixture is stirred while heating until visually observed removal of a visible excess of solvent (acetone), as indicated by the transformation of liquid the state of the solution into a solid. Then the resulting explosive mixture is kept in a fume hood, periodically stirring it to remove the solvent and prevent the mixture from clumping. Then the cured mixture is dried until the solvent (acetone) completely evaporates in a muffle furnace at a temperature not exceeding 60 ° C, which is controlled by the gravimetric method. In the process of weighing, the moment of termination of the evaporation process is determined until the readings of the change in the mass of the solid-phase composition stabilize.

After that, the prepared and dried solid-phase composition is sent to the stage of pressing in a mold at a pressure of at least 50 MPa, a pressing temperature of 90 ± 5 ° C and a pressing process duration of 20 minutes. These conditions were identified and refined experimentally during the control of the density indices of the prototypes. Under these pressing conditions, the required density and strength of the finished product were achieved.

After the completion of all the proposed measures for the method of manufacturing a thermoplastic mixed explosive material, the prototypes were subjected to microstructural studies, studies of gas-dynamic, physicochemical, physical and mechanical parameters. The test results are summarized in Table 1. FIG. 1, fig. 2 (photo) shows a view of the microstructure of the obtained sample of mixed explosives. It can be seen from the photographs that the "BB BNTF-PBMA" composite (2) almost completely covers the surface of the BB - aprol crystals (1), no individual scodings of the "BB BNTF-PBMA" composite (2) were found, which indicates a uniform distribution of components in the mass explosive material.

Thus, when using the proposed components of a mixed heat-sensitive explosive material and measures of the method for its manufacture, a lower level of shock-wave sensitivity is achieved than that achieved in the prototype, while maintaining high power indicators.

The possibility of industrial implementation of the proposed invention is confirmed by the following examples of specific implementation.

Example 1. In laboratory conditions, the proposed mixed explosive material was tested on a sample.

Initially, the components of the mixed explosive material are prepared. The explosive composition contains diaminodinitroethylene (aprol), 3,4-bis- (4-nitrofurazan-3-yl) -furazan (BNTP) as components, and polybutyl methacrylate (PBMA) as an inert additive. The components were taken in the mass ratio. d .: diaminodinitroethylene (aprol) - 87 wt. d., together with (3,4-bis- (4-nitrofurazan-3-yl) -furazan (BNTP) -10 wt. d., polybutyl methacrylate (PBMA) - the rest.

The components of the mixed explosive material - explosive BNTF and PBMA are characterized by good solubility in acetone, insoluble in water, explosive aprol - insoluble in acetone.

The explosive composition was prepared by evaporating the solvent from the mixture of components. The process of obtaining explosive material consists of the following operations:

1 - - soaking a sample of PBMA in acetone for a day, followed by complete dissolution of the acrylic polymer in a solvent;

2 - dissolution of a sample of explosive BNTF in acetone;

3 - mixing solutions of explosive BNTF and PBMA in acetone;

4 - the addition of an acetone solution of the Sudan dye to a solution of the components of the explosives BNTF and PBMA;

5 - adding a sample of BB aprol to the colored acetone solution "PBMA - BB BNTF";

6 - heating the mixture of components in a water bath with constant stirring until the solvent is removed from the system;

7 - weathering of the resulting composition in a fume hood;

8 - drying of the explosive composition in a furnace at T = 60 ° C to constant weight.

When preparing a polymer inert component in the form of polybutyl methacrylate, the latter is mixed with an organic solvent - acetone in a ratio of 1: 5-1: 7 parts by weight, then kept until complete swelling to a gel state, after which the gel-like base of the inert component is introduced into the solution of the energy component of the mixed explosive composition in acetone in a ratio of 1: 3-5, mixed in a mixer until a homogeneous state, after which a second powdery energy component insoluble in acetone is introduced into the resulting homogeneous mixture of components, the mixture is stirred with heating until visually observed removal of a visible excess of solvent, after which keep the mixture in a fume hood, periodically stirring it to remove the solvent and prevent the mixture from clumping, then dry the mixture until the solvent - acetone completely evaporates in a muffle furnace at a temperature of no more than 60 ° C, which is controlled by the gravimetric method, after which the prepared composition is sent to e pressing step in a mold at a pressure of at least 50 MPa.

Example 2. Under the conditions of example 1, the implementation of the proposed method was carried out using a composition where the components were taken in the ratio of masses, d: diaminodinitroethylene (aprol) - 90 masses. d., together with (3,4-bis- (4-nitrofurazan-3-yl) -furazan (BNTP) - 7 wt. d., polybutyl methacrylate (PBMA) - the rest.

Compositions with a different combination of explosive and inert components were also subjected to experimental development in parallel. It has been experimentally confirmed that the proposed invention, in the stated conditions and the claimed limits of the ratios of the components used to obtain the finished product, is characterized by the best technological and physical and mechanical characteristics.

Claims (2)

1. Thermoplastic explosive composition, characterized in that the explosive components contains diaminodinitroethylene, 3,4-bis- (4-nitrofurazan-3-yl) -furazan, and as an inert additive - polybutyl methacrylate in the following ratio of ingredients,% wt. d .: diaminodinitroethylene - 87-93 wt.d. together with 3,4-bis- (4-nitrofurazan-3-yl) -furazan - 4-10 wt.d., polybutyl methacrylate - the rest. 2. A method of manufacturing a thermoplastic mixed explosive composition according to claim 1, including the preparation of its components, mixing the components using a mixing device, characterized by the fact that the initial control of the powdery components of the mixed explosive composition is carried out for compliance with the physicochemical characteristics of the explosive components to the nominal values, and namely, the melting point, the mass fraction of substances insoluble in acetone, moisture, volatile substances, the pH of the aqueous extract, then a weighed portion of the polymer inert component of the mixed explosive composition in the form of polybutyl methacrylate is taken, dissolved in an organic solvent - acetone in a ratio of 1: 5-1: 7 wt. hours, then incubated until complete swelling to the state of a gel, after which the gel-like base of the inert component is introduced into the solution of the energy component of the mixed explosive composition - 3,4-bis- (4-nitrofurazan-3-yl) -furazan in acetone in a ratio of 1: 3-1: 5 parts by weight, mixed in a mixer f until a homogeneous state, after which a second powdery energy component is introduced into the resulting homogeneous mixture of components - diaminodinitroethylene, insoluble in acetone, the mixture is stirred while heating until visually observed removal of a visible excess of solvent - acetone, after which the mixture is kept in a fume hood, stirring occasionally to remove solvent and exclusion of clumping, then the mixture is dried until the solvent - acetone completely evaporates in a muffle furnace at a temperature not exceeding 60 ° C, which is controlled by the gravimetric method, after which the prepared composition is sent to the stage of pressing in a mold at a pressure of at least 50 MPa.

Images