Azo tetrazole ethylenediamine salt compound as well as preparation method and application thereof

Abstract

The invention discloses an azotetrazole ethylenediamine salt compound as well as a preparation method and application thereof. The structural formula of the azotetrazole ethylenediamine salt compound is shown as (I). And reacting the aqueous solution of the compound (II) with the aqueous solution of ethylenediamine hydrochloride at 25-70 DEG C to prepare the azotetrazole ethylenediamine salt compound. The azotetrazole ethylenediamine salt prepared by the invention has good compatibility with a typical propellant, and can be used as a main material of an ejection propellant.

Description

Technical Field

[0001] This invention relates to an energetic material, specifically to an azotetrazole ethylenediamine, its preparation method, and its application. Background Technology

[0002] Missile launch technology, as a crucial component of missile technology, has a vital impact on the survivability and combat effectiveness of missile weapons. Cold launch (ejection) has become an important development direction for missile launch. The propellant (also known as the ejection propellant) is the core of the ejection system, requiring the energetic main material to possess characteristics such as high burning rate, low burning temperature, large gas production, non-hygroscopicity, and clean combustion (no corrosive gases, no smoke), while having relatively low requirements for detonation performance. Currently, domestic and international manufacturers have developed dual-base propellants, ammonium nitrate (AN) propellants, and ammonium perchlorate (AP) propellants. Among them, dual-base propellants have low residue and are relatively clean, best meeting the requirements of propellant generators, but their higher burning temperature affects the overall performance of the propellant. Currently, the energetic main materials used in dual-base propellant generators are octogen and RDX.

[0003] Tetraazole energetic materials possess characteristics such as high enthalpy of formation, fast burning rate, low signal characteristics, and large gas production, thus showing potential advantages in propellant combustion. Tetraazole energetic materials such as azotetrazole diguanidine salt (SZT-2DG) and azotetrazole ditriaminoguanidine salt (SZT-2TG) have been reported. To investigate the influence of energetic material performance on propellant combustion temperature and gas production, a calculation program (REAL software) based on the minimum free energy method was used. Under isobaric adiabatic conditions, a typical basic formulation of a dual-base propellant was used, consisting of 40% nitrocellulose (NC), 30% nitroglycerin (NG), 10% N-nitrodiethanolamine dinitrate (DINA), and 20% energetic main material. The combustion chamber temperature and specific volume of the formulation were theoretically calculated, as shown in Table 1. The calculations show that replacing RDX and HMX with SZT-2TG can significantly increase the nitrogen content and improve the propellant specific impulse, but the increase in specific gas volume and the decrease in combustion temperature are relatively insignificant.

[0004] Table 1. Theoretical performance of different energetic main materials in typical double-base propellant formulations.

[0005] Therefore, there is an urgent need to provide an energetic compound, STZ-YEA (azotetrazole ethylenediamine salt), with a lower combustion chamber temperature and higher gas production, based on structural design, to meet the requirements of catapult propellants. Summary of the Invention

[0006] In view of the defects or deficiencies of the prior art, the present invention provides an azotetrazole ethylenediamine salt compound.

[0007] Therefore, the structural formula of the azotetrazole ethylenediamine salt compound provided by the present invention is shown in (I):

[0008] I.

[0009] The present invention also provides a method for preparing the above-mentioned azotetrazole ethylenediamine salt compound, the method comprising: reacting an aqueous solution of compound (II) with an aqueous solution of ethylenediamine hydrochloride at 25-70°C to prepare the azotetrazole ethylenediamine salt compound; .

[0010] An alternative approach is to dissolve compound (II) in water, add it dropwise to an aqueous solution of ethylenediamine hydrochloride, and then react at 25-70°C.

[0011] An alternative approach is to cool, filter, and wash the filter cake sequentially after the reaction, and then dry the filter cake to recover the azotetraazole ethylenediamine salt.

[0012] An alternative is that the molar ratio of compound (II) to ethylenediamine hydrochloride is 1:1-10.

[0013] The application of the azotetrazole ethylenediamine salt compound of the present invention as an energetic material. The azotetrazole ethylenediamine salt (STZ-YEA) of the present invention, when applied in a typical propellant formulation (40% NC, 30% NG, 10% DINA, and 20% energetic main material), has a theoretical ignition temperature of 2409 K and a gas specific volume of 923.52 L / kg. Compared with the existing azotetrazole ditriaminoguanidine (SZT-2TG), which has a theoretical ignition temperature of 3126 K and a gas specific volume of 680.34 L / kg, the azotetrazole ethylenediamine salt of the present invention better meets the requirements of high gas production and low ignition temperature for projectile propellants.

[0014] This invention also provides corresponding energetic materials, which include the above-mentioned azotetrazole ethylenediamine salt compound and a propellant. The propellant includes nitrocellulose, nitroglycerin, N-nitrodiethanolamine dinitrate, and RDX. The compounds of this invention have good compatibility with typical propellants, are insoluble in water at room temperature, and have good application prospects. Attached Figure Description

[0015] Figure 1 This is a single crystal diagram of the compound STZ-YEA of this invention.

[0016] Figure 2 These are the test results of the thermal decomposition performance of the compounds of this invention. Detailed Implementation

[0017] Unless otherwise specified, the scientific and technical terms used in this article are intended for understanding by those skilled in the art.

[0018] The synthetic route of the compounds in this invention is as follows:

[0019] The compound (I) of the present invention is based on the compound azotetrazole dipotassium salt (II), the structure of which is shown in (II), and the structural formula of the azotetrazole ethylenediamine salt is shown in (I).

[0020] The present invention will be further described in detail below with reference to the embodiments. It should be noted that the embodiments are preferred examples and are mainly used to understand the present invention, but the present invention is not limited to these embodiments. The compound (II) used in the following embodiments was synthesized by the author according to the literature "Synthesis and Characterization of Potassium Azotetrazole and Its Inhibition of Muzzle Flame", Energetic Materials, 22(4), 2014: 478-481.

[0021] Example 1: At 60 °C, 1.0 g of compound (II) (0.0041 mol, molecular weight 262.27 based on the amount of water of crystallization bound to compound II) was dissolved in 20 mL of water, and 10 mL of an aqueous solution of ethylenediamine hydrochloride containing 0.60 mg (0.0045 mol) of ethylenediamine hydrochloride was added dropwise. The mixture was stirred at 60 ± 5 °C for 4 h, cooled to room temperature, filtered, and dried to obtain azotetrazole ethylenediamine salt (STZ-YEA); the yield was 81%. It is a yellow transparent crystalline solid at room temperature.

[0022] Elemental analysis: Molecular formula: C4H 10 N 12 Anal. Calcd (%): C, 21.35; H, 4.62; N, 73.87. Found (%): C, 21.24; H, 4.46; N, 74.31. 13 C NMR (500 MHz, D2O) δ 37.37, 171.75. The single-crystal analysis and data are shown in Table 2.

[0023] Table 2 1 Crystal data and structure refinement for STZ-YEA

[0024] Both structural identification data and single-crystal data confirm that the substance obtained by the above preparation method is azotetrazole ethylenediamine salt.

[0025] Performance testing of the azotetrazole ethylenediamine salt of this invention: (1) Physical and chemical properties Appearance: Yellow transparent crystals Solubility: Slightly soluble in water at room temperature, insoluble in organic solvents such as ethanol, ethyl acetate, acetonitrile, petroleum ether, and n-hexane.

[0026] (2) Thermal decomposition performance Simultaneous thermal analysis (STZ) was performed using a STA 449F3 simultaneous thermal analyzer from Netzsch GmbH, Germany. The test atmosphere was N2, the heating rate was 10℃ / min, and the test temperature range was 40-500℃. Figure 2 The results show that STZ-YEA has an initial decomposition point of 189.1℃, an intermediate decomposition point of 204.4℃, a peak temperature of 198.4℃, and a decomposition heat release area of ​​2252 J / g, exhibiting the characteristics of rapid decomposition and large heat release.

[0027] (3) Compatibility Vacuum stability tests were conducted on STZ-YEA and a typical propellant M (formulation: NC 40%, NG 30%, DINA 10%, RDX 20%) using national standard method 501.2. The mass ratio of STZ-YEA to the typical propellant was 1:1. The mixture was continuously heated at 90℃±0.5℃ for 40 h, and the net outgassing volume was measured. The sample was dried in a vacuum oven at 55℃±2℃ with a vacuum reading not exceeding -0.088 MPa for 2 h. A net outgassing volume R of less than 3.0 mL was considered compatible. The compatibility results of the compounds in this application are shown in Table 3 (the three groups in Table 3 are parallel tests). The results in Table 3 demonstrate that STZ-YEA is compatible with the typical propellant.

[0028] Compatibility is calculated using the formula: R = V C -(V A +V B ) In the formula: R — Net gas release from the reaction, mL; V C —Average gas release rate of the mixed sample, mL; V A —Average gas release rate of gunpowder, explosives or pyrotechnic agents sample, in mL; V B —Average gas release rate of the contact material, mL.

[0029] Table 3

[0030] Furthermore, the azotetraazole ethylenediamine salt (STZ-YEA) of the present invention was applied to a typical propellant formulation (40% NC, 30% NG, 10% DINA, and 20% energetic main material). The results are shown in Table 4, with a theoretical combustion temperature of 2409 K and a gas specific volume of 923.52 L / kg.

[0031] Table 4. Theoretical performance of different energetic main materials in typical double-base propellant formulations.

[0032] The enthalpy of formation, oxygen balance, combustion temperature, specific impulse, characteristic velocity, and gas specific volume in Table 4 are all calculated based on the minimum free energy method.

Claims

1. An azotetrazole ethylenediamine salt compound, the structural formula of which is shown in (I): Ⅰ。 2. The method for preparing the azotetrazole ethylenediamine salt compound according to claim 1, characterized in that, The method includes: reacting an aqueous solution of compound (II) with an aqueous solution of ethylenediamine hydrochloride at 25-70°C to prepare an azotetrazole ethylenediamine salt compound; 。 3. The preparation method according to claim 2, characterized in that, Compound (II) was dissolved in water and added dropwise to an aqueous solution of ethylenediamine hydrochloride, followed by reaction at 25-70°C.

4. The preparation method according to claim 2, characterized in that, After the reaction is complete, the mixture is cooled, filtered, washed, and the filter cake is dried to recover the azotetraazole ethylenediamine salt.

5. The preparation method according to claim 2, characterized in that, The molar ratio of compound (II) to ethylenediamine hydrochloride is 1:1-10.

6. The application of the azotetrazole ethylenediamine salt compound of claim 1 as an energetic material.

7. The application of the azotetrazole ethylenediamine salt compound of claim 1 as an energetic material for projectile propellants.

8. An energetic material, characterized in that, It includes the azotetrazole ethylenediamine salt compound of claim 1 and the propellant.

9. The energetic material according to claim 8, characterized in that, The propellant includes nitrocellulose, nitroglycerin, N-nitrodiethanolamine dinitrate, and RDX.

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