Anionic energetic complex based on mpttz and preparation method and application thereof

Abstract

The application discloses an anion-containing energetic complex based on MPTTz and a preparation method and application thereof, and the method comprises the following steps: taking 6-(3, 5-dimethyl-1H-pyrazol-1-yl)-[1, 2, 4] triazol [4, 3-b] [1, 2, 4, 5] tetrazine and a metal nitrate as raw materials, and preparing by a volatilization method. The anion-containing energetic complex based on MPTTz has a detonation response after laser irradiation, has good safety performance and detonation performance, can be used as a laser initiation explosive, or can be used as a component of a fire explosive and a propellant, and has a good application prospect in the field of high-energy insensitive energetic materials.

Description

Technical Field

[0001] This invention belongs to the field of energetic materials technology. More specifically, this invention relates to an anionic energetic complex based on MPTTz, its preparation method and application. Background Technology

[0002] Energetic complexes are a class of coordination compounds with high explosive properties, showing broad application potential in the field of energetic materials. Their applications mainly fall into two categories: first, as core components of detonators, widely adaptable to the initiation systems of various weapons and ammunition; and second, as energetic catalysts, used in propellant formulations to optimize their combustion performance. However, in the actual preparation process of energetic complexes, solvent molecules readily participate in coordination reactions. Organic solvents (such as ethanol, acetonitrile, dimethylformamide, etc.) or water are used as reaction media. These solvent molecules, possessing a certain coordination ability, easily compete with energetic ligands for coordination sites at the metal center, thus forming energetic complexes containing coordinated solvent molecules. The subsequent release of these coordinated solvent molecules brings two negative impacts: firstly, it directly reduces the energy density of the complex, leading to a decrease in its heat of explosion; secondly, the release of solvent molecules generates additional pressure in the low-temperature range, damaging the structural stability of the energetic complex and severely restricting its performance.

[0003] The energy of energetic complexes originates from redox reactions, and the high oxygen content of oxygen-rich anions is key to achieving high-energy release. Therefore, researchers have dedicated themselves to obtaining energetic complexes containing oxygen-rich anions, and have achieved some success. Currently, the commonly used technique is to introduce anions using the charge difference between high-valence cations and low-valence anion ligands. However, during self-assembly, multiple ligands are often generated and coordinated with the cation, resulting in charge equilibrium and preventing the introduction of anions, leading to significant uncertainty.

[0004] Existing processes typically employ a solvent-antisolvent method to prepare complexes. For example, existing literature (J. Am. Chem. Soc., 2016, 138, 4685–4692) used a solvent-antisolvent method to obtain APTTz-based Fe. 2+ However, this route has significant limitations: firstly, the synthesis process is cumbersome and difficult to scale up, and the product is only partially crystalline, with the remainder being amorphous powder; secondly, this work only achieves ClO4-containing complexes. - Iron-based complexes were obtained, but no other metal-centered complexes such as Ag, Co, Ni, and Cu were obtained, nor were NO3-containing complexes obtained. - The relevant structures of anions. Therefore, it is of great significance to seek a simple, high-yield, and adaptable process for preparing complexes with various metals.

[0005] Meanwhile, with the iterative upgrades of initiation technology, laser initiation technology, with its advantages such as resistance to electromagnetic interference, no risk of electrostatic discharge, and avoidance of stray current influence, has become a safe and reliable new initiation technology in the field of energetic materials. Furthermore, initiating explosives based on coordination compounds are gradually adapting to this technological approach and achieving application. In contrast, existing initiating explosives are still mainly traditional varieties such as lead azide, picric acid, and dinitrodiazophenol (DDNP). These traditional initiating explosives generally suffer from high sensitivity to external stimuli. During production, storage, transportation, and use, they are easily triggered by minor mechanical impacts, static electricity, friction, and other external factors, which can cause not only significant property damage but also personal injury or death.

[0006] In summary, developing novel energetic complex initiators with high energy density and high structural stability, and combining them with the advantages of laser initiation technology to form a suitable initiation scheme to replace existing highly sensitive traditional initiators and solve the problems of insufficient safety and limited energy performance in existing technologies, has become a technical bottleneck that urgently needs to be overcome in the field of energetic materials. Summary of the Invention

[0007] One object of the present invention is to solve at least the above-mentioned problems and / or defects, and to provide at least the advantages described below.

[0008] To achieve these objectives and other advantages of the present invention, an anionic energetic complex based on MPTTz is provided, the general chemical formula of which is [M x (MPTTz) y B z ] n Where n≥1, x ranges from 1 to 5, y ranges from 1 to 5, z ranges from 1 to 5, M is a metal cation, B is an acid radical anion, and MPTTz is 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine.

[0009] Preferably, M is specifically Ag. + Co 2+ Cu 2+ Ni 2+ One of them, B specifically refers to NO3. - ClO4 - One of them.

[0010] Preferably, the MPTTz-based anionic energetic complex specifically comprises: [Ag(MPTTz)(ClO4)] n [Ag2(MPTTz)2(ClO4)2] n[Ag2(MPTTz)2(NO3)2] n [Ag2(MPTTz)(NO3)2] n [Co(MPTTz)3(ClO4)2] n [Cu(MPTTz)3(NO3)2] n [Ni(MPTTz)3(NO3)2] n One of them.

[0011] A method for preparing the above-mentioned MPTTz-based anionic energetic complex includes: using 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine and metal nitrate as raw materials, and preparing the MPTTz-based anionic energetic complex by volatilization.

[0012] Preferably, the method for preparing the MPTTz-based anionic energetic complex specifically includes: first preparing MPTTz for later use, dissolving a metal nitrate in a mixed solution, then adding MPTTz, allowing it to evaporate naturally at room temperature to obtain crystals, i.e., the MPTTz-based anionic energetic complex.

[0013] Preferably, the metal nitrate is one of AgNO3, Co(NO3)2·6H2O, Cu(NO3)2, and Ni(NO3)2·6H2O, and the molar ratio of MPTTz to the metal nitrate is 0.01~3.0:0.01~1.0.

[0014] Preferably, the mixed solution is prepared by mixing H2O with HClO4 or HNO3 in a volume ratio of 4 to 6:1.

[0015] Preferably, the ratio of the metal nitrate to the mixed solution is 0.01~0.03 mmol: 1~20 mL.

[0016] An application of the MPTTz-based anionic energetic complex as described above, wherein the MPTTz-based anionic energetic complex is used as a laser-initiated explosive.

[0017] An application of the MPTTz-based anionic energetic complex as described above, wherein the MPTTz-based anionic energetic complex is used as a combustion catalyst for composite propellants or modified dual-base propellants.

[0018] An application of the MPTTz-based anionic energetic complex as described above, wherein the MPTTz-based anionic energetic complex is used as a catalyst for the decomposition of ammonium perchlorate.

[0019] The present invention provides at least the following beneficial effects: The MPTTz-based anionic energetic complex of the present invention exhibits a detonation response upon laser irradiation, demonstrating excellent safety and detonation performance. It can be used as a laser-initiated explosive or as a component of explosives and propellants, showing promising application prospects in the field of high-energy insensitive energetic materials. Simultaneously, the MPTTz-based anionic energetic complex of the present invention exhibits excellent catalytic activity, reducing the peak temperature of AP high-temperature decomposition by 74°C.

[0020] This invention employs the neutral fused-ring ligand 6-(3,5-dimethyl-1H-pyrazole-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, which has a rich and varied coordination mode, numerous theoretical coordination sites, and chelate coordination, thereby reducing solvent molecule coordination. Furthermore, the anion can fill the channels of the metal-organic framework, effectively increasing density. The ligand 6-(3,5-dimethyl-1H-pyrazole-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine of this invention exhibits good thermal stability, with thermal decomposition stability >300℃. The oxygen-rich anionic energetic complexes constructed by coordinating it with a metal center possess both high energy and low sensitivity. Therefore, the MPTTz-based anionic energetic complexes of this invention generally exhibit excellent thermal stability, all exceeding 200℃. This invention utilizes neutral ligands to obtain oxygen-rich anion-energetic complexes in situ, which provides greater safety and is more suitable for large-scale industrial production.

[0021] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0022] Figure 1 This is a diagram of the minimum asymmetric unit structure of ECP-1 prepared in Example 1 of the present invention; Figure 2 This is a diagram of the minimum asymmetric unit structure of ECP-2 prepared in Example 2 of the present invention; Figure 3 This is a diagram of the minimum asymmetric unit structure of ECP-3 prepared in Example 3 of the present invention; Figure 4 This is a diagram of the minimum asymmetric unit structure of ECP-4 prepared in Example 4 of the present invention; Figure 5 This is a diagram illustrating the laser-initiated detonation process of the ECP-1 prepared in Example 1 of this invention. Figure 6 This is a diagram of the laser-initiated detonation process of ECP-3 prepared in Example 3 of the present invention. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0024] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0025] Example 1 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4-tetraazine (2.06 g, 10.0 mmol), hydrochloric acid (0.6 mL), and triethyl orthoformate (5 mL) were dispersed in 50 mL of 1,4-dioxane and stirred at 100 °C for 24 h. After the reaction was complete, the mixture was filtered and washed with ice water to obtain a yellow powder, yielding 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine (2.0 g, 93%), a yellow powder, MPTTz, with the structural formula […]. ; Step 2: Weigh AgNO3 (169 mg, 1.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HClO4 (volume ratio 4:1). Then add MPTTz (216 mg, 1.0 mmol) and allow it to evaporate naturally at room temperature to obtain yellow needle-like crystals, which are the MPTTz-based anionic energetic complex [Ag(MPTTz)(ClO4)]. n This is designated as ECP-1. Figure 1 This is the minimum asymmetric unit structure diagram of ECP-1.

[0026] Example 2 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4-tetraazine (2.06 g, 10.0 mmol), hydrochloric acid (0.6 mL), and triethyl orthoformate (5 mL) were dispersed in 50 mL of 1,4-dioxane and stirred at 100 °C for 24 h. After the reaction was completed, the mixture was filtered and washed with ice water to obtain a yellow powder, yielding 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine (2.0 g, 93%), which was a yellow powder, MPTTz. Step 2: Weigh AgNO3 (338 mg, 2.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HClO4 (volume ratio 4:1). Then add MPTTz (216 mg, 1.0 mmol) and allow it to evaporate naturally at room temperature to obtain orange needle-like crystals, which are the MPTTz-based anionic energetic complex [Ag2(MPTTz)2(ClO4)2]. n This is designated as ECP-2. Figure 2 This is the minimum asymmetric unit structure diagram of ECP-2.

[0027] Example 3 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4-tetraazine (2.06 g, 10.0 mmol), hydrochloric acid (0.6 mL), and triethyl orthoformate (5 mL) were dispersed in 50 mL of 1,4-dioxane and stirred at 100 °C for 24 h. After the reaction was completed, the mixture was filtered and washed with ice water to obtain a yellow powder, yielding 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine (2.0 g, 93%), which was a yellow powder, MPTTz. Step 2: Weigh AgNO3 (169 mg, 1.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HNO3 (volume ratio 4:1). Then add MPTTz (216 mg, 1.0 mmol) and allow it to evaporate naturally at room temperature to obtain yellow needle-like crystals, which are the MPTTz-based anionic energetic complex [Ag2(MPTTz)2(NO3)2]. n This is designated as ECP-3. Figure 3 This is the minimum asymmetric unit structure diagram of ECP-3.

[0028] Example 4 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4-tetraazine (2.06 g, 10.0 mmol), hydrochloric acid (0.6 mL), and triethyl orthoformate (5 mL) were dispersed in 50 mL of 1,4-dioxane and stirred at 100 °C for 24 h. After the reaction was completed, the mixture was filtered and washed with ice water to obtain a yellow powder, yielding 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine (2.0 g, 93%), which was a yellow powder, MPTTz. Step 2: Weigh AgNO3 (338 mg, 1.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HNO3 (volume ratio 4:1). Then add MPTTz (216 mg, 1.0 mmol) and allow it to evaporate naturally at room temperature to obtain yellow needle-like crystals, which are the MPTTz-based anionic energetic complex [Ag2(MPTTz)(NO3)2]. n This is designated as ECP-4. Figure 4 This is the minimum asymmetric unit structure diagram of ECP-4.

[0029] To determine the structure of the complexes, the crystal structure of the products obtained in Examples 1-4 was tested. The test results are shown in Table 1. Data such as atomic coordinates, coordination bond relationships, and space groups proved that the prepared complexes have novel structures, such as ligand coordination mode, metal-ligand bond length, and anion interaction mode.

[0030] Table 1 Laser-induced detonation test: The complexes [Ag(MPTTz)(ClO4)] prepared in Examples 1 and 3 n [Ag2(MPTTz)2(NO3)2] n A laser-initiated detonation test was conducted. The laser-initiated detonation device consists of a laser optical path system, an initiation system, a data acquisition system, and an illumination optical path. The main functions of the laser optical path system include providing laser light and measuring the energy of a single laser beam (6 mJ). The initiation system is the primary site where the sample responds to the laser. The data acquisition system, consisting of a high-speed camera and a computer, mainly records the deflagration or detonation process of the sample. The illumination optical path is designed to prevent the high-speed camera from being overexposed during recording.

[0031] The laser-initiated detonation process of ECP-1 prepared in Example 1 is shown in the figure below. Figure 5 As shown, [Ag(MPTTz)(ClO4)] n Detonation occurred after 113.15 ms, capturing the moment of deflagration-to-detonation (DDT), with an initiation threshold of 678.9 mJ.

[0032] The laser-initiated detonation process of ECP-3 prepared in Example 3 is shown in the figure below. Figure 6 As shown, [Ag2(MPTTz)2(NO3)2] n Detonation occurred after 134.55 ms, capturing the instant of deflagration-to-detonation (DDT), with an initiation threshold of 807.3 mJ.

[0033] Based on laser-initiated detonation experiments, the performance of the MPTTz-based anionic energetic complex prepared in this invention is far superior to that of the anion-free [Cu(HBTT)(H2O)] complex.n (E = 1.7 J, τ = 432 ms), demonstrating that the introduction of anions plays a significant role in its detonation performance.

[0034] The complex [Ag2(MPTTz)2(NO3)2] prepared in Example 2 n Data on the catalytic decomposition of ammonium perchlorate (AP) were obtained. Adding 5% energetic metal coordination polymer and 10℃ / min can reduce the peak temperature of AP high-temperature decomposition by 74℃, which shows good catalytic effect.

[0035] Example 5 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: Same as in Example 1; Step 2: Weigh Co(NO3)2·6H2O (291 mg, 1.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HClO4 (volume ratio 4:1). Then add MPTTz (216 mg, 1.0 mmol) and allow it to evaporate naturally at room temperature to obtain needle-like crystals, which are the MPTTz-based anionic energetic complex [Co(MPTTz)3(ClO4)2]. n This is designated as ECP-5.

[0036] Example 6 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: Same as in Example 1; Step 2: Weigh Cu(NO3)2 (187 mg, 1.0 mmol) and dissolve it in 5 mL of a mixed solution of H2O and HNO3 (volume ratio 4:1). Then add MPTTz (432 mg, 2.0 mmol) and allow it to evaporate naturally at room temperature to obtain needle-like crystals, which are the MPTTz-based anionic energetic complex [Cu(MPTTz)3(NO3)2]. n This is designated as ECP-6.

[0037] Example 7 A method for preparing anionic energetic complexes based on MPTTz, comprising: Step 1: Same as in Example 1; Step 2: Dissolve 290 mg (1.0 mmol) of Ni(NO3)2·6H2O in 5 mL of a mixed solution of H2O and HNO3 (volume ratio 4:1), then add MPTTz (648 mg, 3.0 mmol). Allow to evaporate naturally at room temperature to obtain needle-like crystals, which are the MPTTz-based anionic energetic complex [Ni(MPTTz)3(NO3)2]. n It is designated as ECP-7.

[0038] Comparative Example 1 MPTTz was prepared first according to the method in Example 1. AgNO3 (169 mg, 1.0 mmol) was weighed and dissolved in 5 mL H2O, and then MPTTz (216 mg, 1.0 mmol) was added. It was allowed to evaporate naturally at room temperature, and no complex was obtained. In this comparative example, HClO4 was not added, and the remaining steps were the same as in Example 1.

[0039] Comparative Example 2 MPTTz was prepared first according to the method in Example 1. AgNO3 (169 mg, 1.0 mmol) was weighed and dissolved in 5 mL H2O, and then MPTTz (233 mg, 1.0 mmol) was added. The mixture was hydrothermally volatilized at 60°C, but no complex was obtained.

[0040] This invention uses MPTTz and silver nitrate as raw materials. By adding perchloric acid or nitric acid to adjust the pH of the system, the ligand ionization is inhibited and it is kept electroneutrally, thereby achieving oxygen-rich anions (ClO4). - NO3 - By directionally introducing MPTTz and then allowing it to evaporate naturally at room temperature, the single-crystal structure of the target complex was successfully prepared. Comparative Examples 1 and 2 show that without external acid adjustment, simply mixing the metal nitrate with MPTTz cannot yield a crystalline product of the complex, regardless of whether room temperature or hydrothermal evaporation methods are used. The selected MPTTz ligand has abundant coordination sites, and its typical chelation coordination mode can significantly enhance its coordination ability with the metal center. By controlling the pH, ligand ionization is suppressed and its electroneutrality is maintained. After the ligand coordinates with the metal center, the system must introduce oxygen-rich anions to achieve charge balance, which is also the key to the stable formation and crystallization of this type of complex.

[0041] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. An anionic energetic complex based on MPTTz, characterized in that, The general chemical formula of the MPTTz-based anionic energetic complex is [M x (MPTTz) y B z ] n Where n≥1, x ranges from 1 to 5, y ranges from 1 to 5, z ranges from 1 to 5, M is a metal cation, B is an acid radical anion, and MPTTz is 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine.

2. The MPTTz-based anionic energetic complex as described in claim 1, characterized in that, The M specifically refers to Ag. + Co 2+ Cu 2+ Ni 2+ One of them, B specifically refers to NO3. - ClO4 - One of them.

3. The MPTTz-based anionic energetic complex as described in claim 1, characterized in that, The MPTTz-based anionic energetic complex specifically includes: [Ag(MPTTz)(ClO4)] n [Ag2(MPTTz)2(ClO4)2] n [Ag2(MPTTz)2(NO3)2] n [Ag2(MPTTz)(NO3)2] n [Co(MPTTz)3(ClO4)2] n [Cu(MPTTz)3(NO3)2] n [Ni(MPTTz)3(NO3)2] n One of them.

4. A method for preparing an anionic energetic complex based on MPTTz as described in any one of claims 1-3, characterized in that, include: Anionic energetic complexes based on MPTTz were prepared by volatilization using 6-(3,5-dimethyl-1H-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine and metal nitrates as raw materials.

5. The method for preparing anionic energetic complexes based on MPTTz as described in claim 4, characterized in that, Specifically, it includes: MPTTz was first prepared for later use. The metal nitrate was dissolved in the mixed solution, and then MPTTz was added. The solution was allowed to evaporate naturally at room temperature to obtain crystals, which are the anionic energetic complexes based on MPTTz.

6. The method for preparing anionic energetic complexes based on MPTTz as described in claim 5, characterized in that, The metal nitrate is one of AgNO3, Co(NO3)2·6H2O, Cu(NO3)2, and Ni(NO3)2·6H2O. The molar ratio of MPTTz to the metal nitrate is 0.01~3.0:0.01~1.

0. The mixed solution is prepared by mixing H2O with HClO4 or HNO3 in a volume ratio of 4~6:

1.

7. The method for preparing anionic energetic complexes based on MPTTz as described in claim 5, characterized in that, The ratio of the metal nitrate to the mixed solution is 0.01~0.03 mmol: 1~20 mL.

8. An application of the MPTTz-based anionic energetic complex as described in any one of claims 1-3, characterized in that, The MPTTz-based anionic energetic complex was used as a laser-initiated explosive.

9. An application of the MPTTz-based anionic energetic complex as described in any one of claims 1-3, characterized in that, The MPTTz-based anionic energetic complex is used as a combustion catalyst for composite propellants or modified dual-base propellants.

10. An application of the MPTTz-based anionic energetic complex as described in any one of claims 1-3, characterized in that, The MPTTz-based anionic energetic complex was used as a catalyst for the decomposition of ammonium perchlorate.

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