Bis-(5-aminotetrazole) borane nitrogen-rich energetic ionic salt (amine) compound

Abstract

The invention discloses a bis-(5-aminotetrazole) borane nitrogen-rich energetic ionic salt (amine) compound. The structural formulas of the bis-(5-aminotetrazole) borane nitrogen-rich energetic ionic salt (amine) compound are shown as (I)-(III). The compound can be used for mixed explosives and fuel-rich propellants.

Description

Technical Field

[0001] This invention belongs to the field of energetic materials, specifically bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salts (amines). Background Technology

[0002] Boron, an element with a unique electronic structure, possesses a small atomic radius (0.87 Å), high electronegativity (2.04), and exhibits both oxophilic and nitrogenophilic properties, demonstrating exceptional engineering value in the design of energetic materials. Boron-based high-stretch bond systems have been identified as a key development direction. These systems precisely embed boron atoms into the molecular framework through BN covalent bonds (bond energy up to 390 kJ / mol), achieving a dual function: firstly, significantly increasing molecular energy density (BN bond energy density is 35% higher than traditional CN bonds); secondly, reconstructing the combustion pathway by forming a BNC bond network, promoting the transformation of combustion products from traditional B2O3 to high-energy boron-nitrogen compounds, effectively overcoming the energy release hindrance effect of the oxide layer. Within this framework, nitrogen heterocyclic compounds, due to their unique structural advantages, become ideal carriers: their abundant high-energy CN / NN bonds (bond energies of 305 kJ / mol and 160 kJ / mol, respectively) endow the system with a high positive enthalpy of formation (ΔH). f The cyclic structure ensures excellent thermal stability (Td>200℃). Constructing azole-boron compounds through a boron-nitrogen synergistic bonding strategy, dispersing boron on the molecular framework of energetic materials to form azole-boron compounds, holds promise for fundamentally solving the problem of incomplete energy release from boron powder and improving the combustion performance of azole-based energetic compounds, providing a theoretical breakthrough for the design of next-generation high-energy propellants. (>300 kJ / mol); cyclic structure ensures excellent thermal stability (Td>200℃).

[0003] The bis-(5-aminotetrazazole)borane synthesized in the prior art has significant shortcomings in detonation performance as a precursor compound. It has a low density (1.50 g·cm⁻³), a slow detonation velocity (7051 m·s⁻¹), a low detonation pressure (17.5 GPa), and limited thermal stability (decomposition temperature 186 °C), which limits its application in high-performance solid propellants or heat-resistant explosives. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salts (amines) to improve detonation performance and thermal stability, and enhance combustion efficiency, thereby providing a new molecular design strategy for the development of next-generation high-performance solid propellants and energetic materials.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: Nitrogen-rich energetic ionic salts (amines) of bis-(5-aminotetrazole)borane include bis-(5-aminotetrazole)boronic acid amine salt (I), bis-(5-aminotetrazole)boronic acid hydroxylamine salt (II), and bis-(5-aminotetrazole)boronic acid hydrazine salt (III), with structural formulas shown in (I) to (III): .

[0006] The synthesis method of the bis-(5-aminotetrazolium)borate amine salt (I) includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazolium)boron in it, and then slowly adding 25% wt% NH3·H2O while stirring for 30 min; directly filtering to obtain a white solid product.

[0007] The present invention also includes the following technical features: Specifically, the ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and NH3·H2O is 2 ml: 2 mmol: 2 mmol.

[0008] The method for synthesizing the bis-(5-aminotetrazolium)borate hydroxylamine salt (II) includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazolium)boron in it, then slowly adding 50% wt% NH2OH and stirring for 30 min; and directly filtering to obtain a white solid product.

[0009] Specifically, the ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and NH2OH is 2 ml: 2 mmol: 2 mmol.

[0010] The method for synthesizing the nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazole)borane is characterized in that the method for synthesizing the hydrazine salt (III) of bis-(5-aminotetrazole)boron includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazole)boron in it, and then slowly adding wt%=80% N2H4·H2O dropwise while stirring for 30 min; directly filtering to obtain a white solid product.

[0011] Specifically, the ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and N2H4·H2O is 2 ml: 2 mmol: 2 mmol.

[0012] Compared with the prior art, the present invention has the following technical effects: The three bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salts (amines) synthesized in this invention significantly outperformed their precursor compounds in terms of density and detonation performance. Among them, compound (III) exhibited the greatest improvement over the precursor compound (density 1.50 g·cm⁻³, decomposition temperature 186℃, detonation velocity 7051 m·s⁻¹, detonation pressure 17.5 GPa), with a 65.14% increase in detonation pressure and a 25.78% increase in detonation velocity, while maintaining good sensitivity (FS>360 N, IS>40 J). These results indicate that this type of compound can be applied in fuel-rich propellant formulations or heat-resistant explosives.

[0013] In terms of synthesis, since bis-(5-aminotetrazazole)borane itself contains a -BH2 group, it is not suitable for traditional silver salt ion conversion. In this invention, the corresponding nitrogen-rich explosive group is directly reacted with an alkaline aqueous solution to obtain three nitrogen-rich energetic ion salts (amines). By strictly controlling the mass fraction of the aqueous solution, the BN bond breaking caused by excessive alkalinity is avoided, thereby improving the reaction efficiency. Attached Figure Description

[0014] Figure 1 This is a single-crystal molecular structure diagram of bis-(5-aminotetrazolium)borate amine salt (I).

[0015] Figure 2 This is a single-crystal molecular structure diagram of hydroxylamine bis-(5-aminotetrazazole)borate (II). Detailed Implementation

[0016] This invention provides a nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazazole)borane, comprising bis-(5-aminotetrazazole)boronic acid amine salt (I), bis-(5-aminotetrazazole)boronic acid hydroxylamine salt (II) and bis-(5-aminotetrazazole)boronic acid hydrazine salt (III), the structural formulas of which are shown in (I) to (III): .

[0017] This invention uses bis-(5-aminotetrazazole)borane synthesized in the prior art as a precursor, the structure of which is shown in compound (IV): .

[0018] The synthetic route for the nitrogen-rich energetic ionic salt compound of bis-(5-aminotetrazazole)borane in this invention is as follows:

[0019] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0020] Example 1: This embodiment provides a nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazazole)borane, specifically bis-(5-aminotetrazazole)boronic acid amine salt (I). The synthesis method of bis-(5-aminotetrazazole)boronic acid amine is as follows: At 25°C, 2 ml of anhydrous ethanol is added to a 10 ml single-necked flask, and 362 mg (2 mmol) of bis(5-aminotetrazazole)borane is dissolved in it. Then, 280 mg (wt%=25%, 2 mmol) of NH3·H2O is slowly added dropwise while stirring for 30 min. Direct filtration yields 316 mg of a white solid, with a yield of 79.8%.

[0021] Structural assessment: Bis-(5-aminotetrazole)borate ammonium salt (I): Infrared spectrum: IR(KBr), v (cm -1 ): 3411, 3334, 3201, 1651, 1587, 1448, 1265, 1145, 1091, 1067, 1049, 999, 775, 736, 680, 443; Nuclear magnetic resonance spectroscopy:

[0022] Elemental analysis: Molecular formula: C2H 10 N 11 B Theoretical values: C 12.06, H 5.02, N 77.19; Measured values: C 11.98, H 5.76, N 76.83.

[0023] Single crystal structure analysis: Figure 1 Single-crystal molecular structure diagram of bis-(5-aminotetrazazole)borate amine salt (I) (nitrogen, blue; carbon, gray; hydrogen, white; oxygen, red; boron, yellow) Table 1 Crystal data and structural refinement parameters of bis-(5-aminotetrazolium)borate (I)

[0024] Properties of bis-(5-aminotetrazolium)borate ammonium salt (I): (1) Physical and chemical properties Density: 1.54 g / cm³ 3 True density method Thermal decomposition onset temperature: 207 ℃ (DSC method) (2) Detonation performance Detonation velocity: density is 1.54 g / cm³ 3 The calculated detonation velocity is 8.31 km / s (EXPLO5 6.04). Explosion pressure: density is 1.54 g / cm³ 3 The calculated burst pressure is 23.3 GPa (EXPLO5 6.04). Heat of combustion: density 1.54 g / cm³ 3 The heat of combustion was 16502 kJ / kg, as tested by the oxygen bomb tester. Enthalpy of formation: density 1.54 g / cm³ 3 The enthalpy of formation was calculated to be 450 kJ / mol using the Gaussian 09 program B3LYP / 6-31G** method. (3) Safety performance Impact sensitivity: >40 JWL-1 type impact sensitivity meter Friction sensitivity: >360 NWM-1 friction sensitivity meter Example 2: This embodiment provides a nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazazole)borane, specifically hydroxylamine bis-(5-aminotetrazazole)borate (II). The synthesis method of hydroxylamine bis-(5-aminotetrazazole)borate is as follows: At 25°C, 2 ml of anhydrous ethanol is added to a 10 ml single-necked flask, and 362 mg (2 mmol) of bis(5-aminotetrazazole)borane is dissolved in it. Then, 132 mg (wt%=50%, 2 mmol) of NH₂OH is slowly added dropwise while stirring for 30 min. Direct filtration yields 247 mg of a white solid, with a yield of 57.7%.

[0025] Structural assessment: Bis-(5-aminotetrazole)borate hydroxylamine salt (II): Infrared spectrum: IR(KBr), v (cm -1 ): 3429, 3336, 3219, 2721, 2501, 1625, 1568, 1467, 1299, 1228, 1134, 1074, 1002, 871, 761, 642, 435 Nuclear magnetic resonance spectroscopy:

[0026] Elemental analysis: Molecular formula: C2H 10 N 11 OB Theoretical values: C 11.16, H 4.65, N 71.63; Measured values: C 11.98, H 5.16, N 76.83.

[0027] Single crystal structure analysis: Figure 2 Single-crystal molecular structure diagram of hydroxylamine bis(5-aminotetrazole)borate (II) (nitrogen, blue; carbon, gray; hydrogen, white; oxygen, red; boron, yellow).

[0028] Table 2 Crystal data and structural refinement parameters of bis-(5-aminotetrazolium)borate hydroxylamine salt (II)

[0029] Properties of bis-(5-aminotetrazole)borate hydroxylamine salt(II): (1) Physical and chemical properties Density: 1.58 g / cm³ 3 True density method Thermal decomposition initiation temperature: 237 ℃ (DSC method) (2) Detonation performance Detonation velocity: density is 1.58 g / cm³ 3 The calculated detonation velocity is 8.78 km / s (EXPLO5 6.04). Explosion pressure: density is 1.58 g / cm³ 3 The calculated burst pressure is 27.5 GPa (EXPLO5 6.04). Heat of combustion: density 1.58 g / cm³ 3 The heat of combustion was 15902 kJ / kg, as tested by the oxygen bomb tester. Enthalpy of formation: density 1.58 g / cm³ 3 The enthalpy of formation was calculated to be 507 kJ / mol using the Gaussian 09 program B3LYP / 6-31G** method. (3) Safety performance Impact sensitivity: >40 JWL-1 type impact sensitivity meter Friction sensitivity: >360 NWM-1 friction sensitivity meter Example 3: This embodiment provides a nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazole)borane, specifically bis-(5-aminotetrazole)borate hydrazine (III). The synthesis method of bis-(5-aminotetrazole)borate hydrazine is as follows: At 25°C, 2 ml of anhydrous ethanol is added to a 10 ml single-necked flask, and 362 mg (2 mmol) of bis(5-aminotetrazole)borane is dissolved in it. Then, 125 mg (wt%=80%, 2 mmol) of N₂H₄·H₂O is slowly added dropwise while stirring for 30 min. Direct filtration yields 298 mg of a white solid, with a yield of 71.3%.

[0030] Structural assessment: Bis-(5-aminotetrazole)borate hydrazine (III): Infrared spectrum: IR(KBr), v (cm -1 ): 3415, 3303, 3194, 2970, 2715, 2229, 1627, 1514, 1436, 1224, 1114, 1014, 960, 804, 750, 530, 430 Nuclear magnetic resonance spectroscopy:

[0031] Elemental analysis: Molecular formula: C2H 11 N 12 B Theoretical values: C 11.21, H 5.14, N 78.50; Measured values: C 11.38, H 5.35, N 79.26.

[0032] Properties of bis-(5-aminotetrazole)borate hydrazine (III): (1) Physical and chemical properties Density: 1.56 g / cm³ 3 Gaussian 09 program B3LYP / 6-31G** method Thermal decomposition initiation temperature: 227 ℃ (DSC method) (2) Detonation performance Detonation velocity: density is 1.56 g / cm³ 3 The calculated detonation velocity is 8.86 km / s (EXPLO5 6.04). Explosion pressure: density is 1.56 g / cm³ 3 The calculated burst pressure is 28.9 GPa (EXPLO5 6.04). Heat of combustion: density 1.56 g / cm³ 3 The heat of combustion was 16630 kJ / kg, as tested by the oxygen bomb tester. Enthalpy of formation: density 1.56 g / cm³ 3 The enthalpy of formation was calculated to be 603 kJ / mol using the Gaussian 09 program B3LYP / 6-31G** method. (3) Safety performance Impact sensitivity: >40 JWL-1 type impact sensitivity meter Friction sensitivity: >360 NWM-1 friction sensitivity meter The three bis-(5-aminotetrazolium)borane nitrogen-rich energetic ionic salts (amines) synthesized in this invention can be used in the fields of mixed explosives and fuel-rich propellants.

Claims

1. A nitrogen-rich energetic ionic salt (amine) compound of bis-(5-aminotetrazazole)borane, characterized in that, Including bis-(5-aminotetrazole)borate amine salt (I), bis-(5-aminotetrazole)borate hydroxylamine salt (II), and bis-(5-aminotetrazole)borate hydrazine salt (III), with structural formulas shown in (I)~(III): 。 2. The method for synthesizing the bis-(5-aminotetrazolium)borane nitrogen-rich energetic ionic salt (amine) compound according to claim 1, characterized in that, The synthesis method of the bis-(5-aminotetrazolium)borate amine salt (I) includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazolium)boron in it, and then slowly adding 25% wt% NH3·H2O while stirring for 30 min; directly filtering to obtain a white solid product.

3. The method for synthesizing the bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salt (amine) compound as described in claim 2, characterized in that, The ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and NH3·H2O is 2 ml: 2 mmol: 2 mmol.

4. The method for synthesizing the bis-(5-aminotetrazolium)borane nitrogen-rich energetic ionic salt (amine) compound according to claim 1, characterized in that, The method for synthesizing the bis-(5-aminotetrazolium)borate hydroxylamine salt (II) includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazolium)boron in it, then slowly adding 50% wt% NH2OH and stirring for 30 min; and directly filtering to obtain a white solid product.

5. The method for synthesizing the bis-(5-aminotetrazolium)borane nitrogen-rich energetic ionic salt (amine) compound as described in claim 4, characterized in that, The ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and NH2OH is 2 ml: 2 mmol: 2 mmol.

6. The method for synthesizing the bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salt (amine) compound according to claim 1, characterized in that, The method for synthesizing the bis-(5-aminotetrazolium)borate hydrazine (III) includes: adding anhydrous ethanol to a single-necked flask at 25°C, dissolving bis(5-aminotetrazolium)boron in it, then slowly adding wt%=80% N2H4·H2O dropwise while stirring for 30 min; and directly filtering to obtain a white solid product.

7. The method for synthesizing the bis-(5-aminotetrazazole)borane nitrogen-rich energetic ionic salt (amine) compound as described in claim 6, characterized in that, The ratio of anhydrous ethanol, bis(5-aminotetrazolium)boron, and N2H4·H2O is 2 ml: 2 mmol: 2 mmol.

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