Triazolotetrazine energetic ionic liquid as well as preparation method and application thereof

Abstract

The invention discloses triazolo tetrazine energetic ionic liquid and a preparation method and application thereof, and belongs to the technical field of energetic materials, the preparation method comprises the following steps: mixing N6-(1, 3, 4-oxadiazole-2-yl)-[1, 2, 4] triazolo [4, 3-b] [1, 2, 4, 5] tetrazine and fat type quaternary ammonium base, heating to react, removing a solvent after the reaction is finished, and drying to obtain the triazolo tetrazine energetic ionic liquid. And the triazolotetrazine energetic ionic liquid is obtained. The triazolotetrazine energetic ionic liquid prepared by the invention has the performance advantages of high enthalpy of formation, good stability and low sensitivity, has application potential in the aspect of novel solid high-energy propellants, and is simple in preparation method, easy to synthesize and high in yield.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energetic materials, and particularly relates to a triazolotetrazolium energetic ionic liquid and a preparation method and application thereof. BACKGROUND

[0002] In the research field of solid propellants, energetic plasticizers occupy a very key position, and it is the core element to improve the energy release level and optimize the mechanical properties of propellants. The ideal energetic plasticizer often has the characteristics of high enthalpy of formation, low glass transition temperature, weak volatility and excellent compatibility with other substances, and it has always been the focus of attention in the field of solid propellant research.

[0003] Energetic ionic liquids have extremely low volatility and can remain stable even in high temperature environments. Their high thermal stability makes them reliable under complex working conditions, and their designability gives researchers a great creative space, and their high energy density provides strong support for improving propellant performance. These unique advantages make energetic ionic liquids have immeasurable application potential in replacing traditional plasticizers and improving propellant performance.

[0004] Currently, the synthesis path of ionic liquids is often used to modify the anion and cation. Specifically, energetic groups such as azide and nitro groups are introduced to successfully synthesize a large number of new energetic ionic liquids. Compared with traditional covalent energetic materials, energetic ionic liquids have a unique internal mechanism. They rely on the strong electrostatic interaction between anions and cations and the buffer force generated by the "cavity" between ions to enhance the internal force of the compound, thereby greatly reducing the sensitivity of the energetic material.

[0005] By carefully adjusting the energetic groups on the anion and cation, the energy level of the energetic ionic liquid can be effectively improved. In energetic ionic liquids, the cation is mostly imidazole derivatives, and triazolium and furazan cations have been successfully developed by existing technology. The high-nitrogen anion is also diverse, such as azide group, dicyanamide group, and dinitramide group. Currently, researchers have prepared a large number of energetic ionic liquids by flexibly changing the types and proportions of anions. According to their different properties, these energetic ionic liquids can be used as key components such as energetic plasticizers, energetic binders, and liquid fuels in propellants.

[0006] In addition to energetic ionic liquids, condensed ring high-nitrogen compounds have also attracted much attention. It has the outstanding characteristics of high enthalpy of formation, large density and good stability, and is considered as a new type of energetic material that can balance energy and sensitivity. In recent years, it has become a hot research field. However, there is a π-π stacking phenomenon between the molecules of condensed nitrogen compounds, which makes its structure too rigid, and basically presents in solid form. This characteristic limits its wide application in the field of propellants to some extent.

[0007] Therefore, how to provide a triazolotetrazine energetic ionic liquid is a technical problem that those skilled in the art urgently need to solve. SUMMARY

[0008] To solve the above technical problems, the present application provides a triazolotetrazine energetic ionic liquid and its preparation method and application.

[0009] To achieve the above purpose, the present application provides the following technical solutions:

[0010] A triazolotetrazine energetic ionic liquid, the structure of which is shown in formula (I):

[0011]

[0012] (I);

[0013] Among them, R1, R2, R3, R4 are independently selected from -C n H n+2 ; further preferably, the triazolotetrazine energetic ionic liquid comprises the following structure:

[0014] .

[0015] A preparation method of a triazolotetrazine energetic ionic liquid, comprising the following steps:

[0016] N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine is mixed with an aliphatic quaternary ammonium base and heated to react. After the reaction is completed, the solvent is removed and dried to obtain the triazolotetrazine energetic ionic liquid.

[0017] Preferably, the heating reaction temperature is 20-50℃, and the time is 0.5-2h.

[0018] Preferably, the N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine and the aliphatic quaternary ammonium base have a molar ratio of 1:2.

[0019] Preferably, the N6 The preparation method of (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine comprises the following steps:

[0020] After mixing 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine, a catalyst and a solvent, the reaction is carried out under heating, and after the reaction is completed, the post-treatment is carried out, thereby obtaining the N 6 (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine.

[0021] Preferably, the catalyst is selected from one or more of cesium carbonate, potassium carbonate, sodium carbonate and triethylamine; and / or,

[0022] The solvent is selected from one or more of acetonitrile, methanol, ethanol, dioxane or N,N-dimethylformamide.

[0023] Preferably, the molar ratio of 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine and the catalyst is 1:(1-2):(0.5-2).

[0024] Preferably, the temperature of the reaction is 50-120°C, and the time is 2-12h.

[0025] Preferably, the fatty quaternary ammonium base is obtained by anion exchange of a fatty quaternary ammonium salt.

[0026] The fatty quaternary ammonium salt is selected from one of methyltrioctylammonium chloride, dipdecyldimethylammonium chloride or dioctyldimethylammonium chloride.

[0027] More preferably, the anion exchange is completed by using an anion resin in an ion exchange column.

[0028] More preferably, the anion resin is one of D001 anion resin, D201 anion resin or 201x7 anion resin.

[0029] More preferably, the height-diameter ratio of the ion resin column is 1:1-3:1, and the molar mass of the quaternary ammonium salt is less than the maximum exchange capacity of the resin column.

[0030] Preferably, the post-treatment comprises acid pH adjustment, solid-liquid separation, washing and drying.

[0031] More preferably, the acid comprises any one or a combination of at least two of hydrochloric acid, nitric acid or sulfuric acid.

[0032] More preferably, the concentration of the acid is 0.5-6 mol / L;

[0033] More preferably, the molar ratio of the acid to 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine is (2-7):1;

[0034] More preferably, the end point of the pH adjustment is 3-4;

[0035] More preferably, the drying temperature is 25-60 DEG C.

[0036] Application of triazolotetrazine energetic ionic liquid in solid propellant.

[0037] Compared with the prior art, the application has the following advantages and technical effects:

[0038] The application can meet the requirement of different components of propellant for improving energy by means of ion salt to liquidate condensed nitrogen compound. The triazolotetrazine energetic ionic liquid provided by the application not only inherits the core advantages of traditional energetic ionic liquid, but also exhibits excellent performance in terms of formation enthalpy, safety, synthesis convenience and continuous production adaptability. Specifically, the energetic ionic liquid has the characteristics of high formation enthalpy, which ensures high energy density; the excellent safety provides reliable guarantee for the use of propellant; meanwhile, the simple synthesis path and efficient continuous production process make large-scale preparation possible. In the application level, the energetic ionic liquid can significantly optimize the forming process of solid propellant and greatly improve the energy level, thereby giving the energetic ionic liquid a broad application prospect in the field of new solid high-energy propellant. In addition, the preparation method provided by the application is simple and easy to operate, has high synthesis efficiency and considerable yield, and has great application value. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and serve as an aid in explaining the illustrative embodiments of the present application and their descriptions are used to explain the present application. The present application is not limited by the accompanying drawings.

[0040] Figure 1 NMR spectrum of [bis (octyl dimethyl ammonium) ] [N 6 NMR spectrum of [bis (octyl dimethyl ammonium) ] [N

[0041] Figure 2 NMR spectrum of [bis (octyl dimethyl ammonium) ] [N 6NMR carbon spectrum of [bisdecyldimethylammonium] [N

[0042] Figure 3 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 IR spectrum of [bisdecyldimethylammonium] [N

[0043] Figure 4 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 Melting point plot of [bisdecyldimethylammonium] [N

[0044] Figure 5 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 Decomposition temperature plot of [bisdecyldimethylammonium] [N

[0045] Figure 6 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 NMR hydrogen spectrum of [bisdecyldimethylammonium] [N

[0046] Figure 7 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 NMR hydrogen spectrum of [bisdecyldimethylammonium] [N

[0047] Figure 8 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 IR spectrum of [bisdecyldimethylammonium] [N

[0048] Figure 9 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6 Melting point plot of [bisdecyldimethylammonium] [N

[0049] Figure 10 NMR carbon spectrum of [bisdecyldimethylammonium] [N 6a decomposition temperature graph of [methyltrioctylammonium] [N

[0050] Figure 11 a decomposition temperature graph of [methyltrioctylammonium] [N 6 a nuclear magnetic resonance hydrogen spectrum graph of [methyltrioctylammonium] [N

[0051] Figure 12 a decomposition temperature graph of [methyltrioctylammonium] [N 6 a nuclear magnetic resonance carbon spectrum graph of [methyltrioctylammonium] [N

[0052] Figure 13 a decomposition temperature graph of [methyltrioctylammonium] [N 6 an infrared spectrum graph of [methyltrioctylammonium] [N

[0053] Figure 14 a decomposition temperature graph of [methyltrioctylammonium] [N 6 a melting point graph of [methyltrioctylammonium] [N

[0054] Figure 15 a decomposition temperature graph of [methyltrioctylammonium] [N 6 a decomposition temperature graph of [methyltrioctylammonium] [N

[0055] Figure 16 a diagram showing the influence of different plasticizers on the specific impulse of propellants in application examples 1-3 and comparative application examples 1-2. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0057] In order to make the above objectives, characteristics and advantages of the present application more apparent and comprehensible, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0058] The raw materials in the embodiments of the present application are commercially available unless otherwise specified.

[0059] The room temperature or normal temperature in the embodiments of the present application refers to 25±3℃ unless otherwise specified.

[0060] Example 1

[0061] A [bis (octyl dimethyl ammonium) ] [N 6 The synthesis method of the energetic plasticizer of [bis (octyl dimethyl ammonium) ] [N

[0062] (1) An ion exchange column with a diameter of 40 mm, a resin filling height of 120 mm, and a height-diameter ratio of 3:1 was selected, 201x7 anion resin was filled in the ion exchange column, and the mass of the resin was 105.5 g (wet resin with surface water removed), the resin column was activated and reserved. 30.6 g of bis (octyl dimethyl ammonium) chloride was dissolved in 200 mL of anhydrous ethanol, slowly added to the activated 201x7 anion resin exchange column, and the column liquid was allowed to flow out from the bottom at a flow rate of 3-4 mL / min, then 200 mL of anhydrous ethanol was added to elute the bis (octyl dimethyl ammonium) hydroxide in the resin column, the column bottom effluent was collected, and the volume was made up to 500 mL to prepare a bis (octyl dimethyl ammonium) hydroxide solution with a concentration of 0.2 mol / L.

[0063] (2) 10.0 g (0.046 mol) of 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 4.7 g (0.055 mol) of 1,3,4-oxadiazol-2-amine, 7.5 g (0.023 mol) of cesium carbonate and 100 mL of acetonitrile were placed in a three-necked flask, wherein the molar ratio of 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine and the catalyst (cesium carbonate) was 1:1.2:0.5, and the mass ratio of the solvent (acetonitrile) to 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 7.9:1, and after being uniformly mixed, the condensation reflux reaction was carried out at a temperature of 80°C for 6 h, and then cooled to room temperature. After the reaction was completed, 75 mL of hydrochloric acid with a concentration of 4 mol / L was added dropwise into the reaction solution to adjust the pH of the reaction solution to 3, wherein the molar ratio of HCl in the hydrochloric acid to 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 6.5:1, and stirred for 0.5 h, and then filtered, and the filter cake was washed with deionized water and acetonitrile for 2 times respectively, and then dried to obtain N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine 8.3 g, with a yield of 87.0%.

[0064] (3) 4 g of N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine obtained in step (2), 79.1 mL of the bis (octyl dimethyl ammonium) hydroxide solution with a concentration of 0.2 mol / L obtained in step (1) were placed in a flask, and stirred at a temperature of 50°C for 2 h, and then cooled to room temperature, and the solvent was distilled under reduced pressure to obtain a triazolotetrazine energetic plasticizer [bis (octyl dimethyl ammonium) ] [N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine], denoted as DODA-DTOZ.

[0065] The triazolotetrazine energetic plasticizer [bis (octyl dimethyl ammonium) ] [N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] obtained was subjected to nuclear magnetic resonance hydrogen spectrum, carbon spectrum and infrared spectrum analysis, and the results were as follows: 1H NMR (600 MHz, DMSO-d6): δ (ppm) = 9.17 (s, 1H), 8.55 (s, 1H), 3.25–3.14(m, 4H), 2.98 (s, 6H), 1.63 (m, 4H), 1.28–1.21 (m, 20H), 0.85 (t, 6H). 13 C NMR(151 MHz, DMSO-d6) δ (ppm) = 164.02, 157.71, 148.72, 148.67, 135.92, 62.89,52.16, 49.97, 31.27, 31.15, 28.99, 28.87, 28.76, 28.65, 28.43, 28.41, 25.75,25.73, 22.08, 22.03, 22.01, 13.93. IR γ (cm - ¹): 3093, 3027, 2925, 2855,1609, 1553, 1529, 1483, 1466, 1376, 1108, 1035, 963, 775, 725.

[0066] From nuclear magnetic resonance hydrogen spectrum ( Figure 1 ), nuclear magnetic resonance carbon spectrum ( Figure 2 ) and infrared spectrum ( Figure 3 It can be determined that the obtained black ionic liquid is the target product [bis(octyl)dimethylammonium)][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine], the structural formula of the target product is as follows:

[0067]

[0068] The obtained [bisoctyldimethylammonium][N] 6 [-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine] was subjected to DSC testing, and the results are as follows: Figure 4 and 5 As shown, the glass transition temperature is -20.0℃ and the decomposition temperature is 129.6℃.

[0069] Using Gaussian 09 software, the [bisoctyldimethylammonium][N] energy cycle was calculated at the M06-2X-D3 / def2-TZVPP basis set level using the Born-Haber energy cycle. 6The standard molar enthalpy of formation of [bisdecyldimethylammonium][N 6 The impact sensitivity of [bisdecyldimethylammonium][N

[0070] Example 2

[0071] A [bisdecyldimethylammonium][N 6 The synthesis method of the energetic plasticizer of [bisdecyldimethylammonium][N

[0072] (1) An ion exchange column with a diameter of 40 mm, a resin filling height of 120 mm, and a height-diameter ratio of 3:1 was selected, 201x7 anion resin was filled in the ion exchange column, and the mass of the resin was 105.5 g (wet resin with surface water removed). After the resin column was activated, it was ready for use. 36.2 g of bisdecyldimethylammonium chloride was dissolved in 200 mL of anhydrous ethanol, slowly added to the activated 201x7 anion resin exchange column, and the column liquid was allowed to flow out from the bottom of the column at a flow rate of 3-4 mL / min. Then, 200 mL of anhydrous ethanol was added to elute the bisdecyldimethylammonium hydroxide in the resin column, and the column bottom effluent was collected. The volume was made up to 500 mL to prepare a bisdecyldimethylammonium hydroxide solution with a concentration of 0.2 mol / L.

[0073] (2) 10.0 g (0.046 mol) of 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 4.7 g (0.055 mol) of 1,3,4-oxadiazol-2-amine, 7.5 g (0.023 mol) of cesium carbonate and 100 mL of acetonitrile were added into a three-necked flask, wherein the molar ratio of 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine and the catalyst (cesium carbonate) was 1:1.2:0.5, the mass ratio of the solvent (acetonitrile) to 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 7.9:1, and after being uniformly mixed, the condensation reflux reaction was carried out at 80°C for 6 h, and then cooled to room temperature. After the reaction was completed, 75 mL of hydrochloric acid with a concentration of 4 mol / L was added dropwise into the reaction solution to adjust the pH of the reaction solution to 3, wherein the molar ratio of HCl in the hydrochloric acid to 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 6.5:1, stirred for 0.5 h, and then filtered under suction, and after the filter cake was washed with deionized water and acetonitrile respectively for 2 times, dried to obtain N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine 8.3 g, with a yield of 87.0%.

[0074] (3) 4 g of N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine obtained in step (2), 79.1 mL of the didecyldimethylammonium hydroxide solution with a concentration of 0.2 mol / L obtained in step (1) were placed into a flask, and stirred at 50°C for 2 h, and then cooled to room temperature after the reaction was completed, and the solvent was distilled under reduced pressure to obtain a triazolotetrazine energetic plasticizer [didecyldimethylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine], denoted as DDA-DTOZ.

[0075] The triazolotetrazine energetic plasticizer [didecyldimethylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] obtained was subjected to nuclear magnetic resonance hydrogen spectrum, carbon spectrum and infrared spectrum analysis, and the results were as follows: 1H NMR (600 MHz, DMSO-d6): δ (ppm) = 9.09 (s, 1H), 8.47 (s, 1H), 3.26–3.17(m, 4H), 2.98 (s, 6H), 1.67–1.58 (m, 4H), 1.26 (m, 28H), 0.85 (t, 6H). 13 C NMR(151 MHz, DMSO-d6) δ (ppm) = 165.13, 158.49, 148.51, 148.47, 135.75, 62.85,49.98, 31.27, 28.87, 28.76, 28.65, 28.43, 25.73, 22.08, 21.63, 13.93. IR γ(cm - ¹): 3401, 3096, 3027, 2926, 2855, 1551, 1464, 1414, 1374, 1229, 1111,1035, 724.

[0076] From nuclear magnetic resonance hydrogen spectrum ( Figure 6 ), nuclear magnetic resonance carbon spectrum ( Figure 7 ) and infrared spectrum ( Figure 8 It can be determined that the obtained black ionic liquid is the target product [disdecyldimethylammonium][N] 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine], the structural formula of the target product is as follows:

[0077]

[0078] The obtained [disdecyldimethylammonium][N] 6 [-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine] was subjected to DSC testing, and the results are as follows: Figures 9-10 As shown, the glass transition temperature is -46.1℃ and the decomposition temperature is 173.0℃.

[0079] Using Gaussian 09 software, the [bisdecyldimethylammonium][N] energy cycle was calculated at the M06-2X-D3 / def2-TZVPP basis set level using the Born-Haber energy cycle. 6 The standard molar enthalpy of formation of [-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine] is 463.0 kJ / mol. [bisdecyldimethylammonium][N 6The impact sensitivity of (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazine] is > 50 J, and the friction sensitivity is > 360 N.

[0080] Example 3

[0081] A [methyltrioctylammonium][N 6 The synthesis method of the energetic plasticizer (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazine] comprises the following steps:

[0082] (1 ) An ion exchange column with a diameter of 40 mm, a resin loading height of 120 mm, and a height-diameter ratio of 3:1 was selected, and 201 x 7 anion resin was loaded into the ion exchange column, with the mass of the resin being 105.5 g (wet resin with surface water removed). After activation of the resin column, it was ready for use. 404.2 g of methyltrioctylammonium chloride was dissolved in 200 mL of anhydrous ethanol, and then slowly added to the activated 201 x 7 anion resin exchange column. The flow rate was 3-4 mL / min, and the column effluent flowed out from the bottom of the column. Then 200 mL of anhydrous ethanol was added to elute the methyltrioctylammonium hydroxide in the resin column. The column effluent was collected, and the volume was made up to 500 mL to prepare a 0.2 mol / L methyltrioctylammonium hydroxide solution.

[0083] (2) 10.0 g (0.046 mol) of 6-(3,5-dimethyl-pyrazol-1 -yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazine, 4.7 g (0.055 mol) of 1,3,4-oxadiazol-2-amine, 7.5 g (0.023 mol) of cesium carbonate, and 100 mL of acetonitrile were added to a three-necked flask, wherein the molar ratio of 6-(3,5-dimethyl-pyrazol-1 -yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine, and catalyst (cesium carbonate) was 1 :1.2:0.5, and the mass ratio of solvent (acetonitrile) to 6-(3,5-dimethyl-pyrazol-1 -yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 7.9:1. After mixing uniformly, the mixture was condensed and refluxed at 80°C for 6 h, and then cooled to room temperature. After the reaction was completed, 75 mL of 4 mol / L hydrochloric acid was added dropwise to the reaction solution to adjust the pH of the reaction solution to 3, wherein the molar ratio of HCl in the hydrochloric acid to 6-(3,5-dimethyl-pyrazol-1 -yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine was 6.5:1. After stirring for 0.5 h, the mixture was filtered, and the filter cake was washed with deionized water and acetonitrile for 2 times, respectively, and then dried to obtain N 6-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine 8.3 g, yield 87.0%.

[0084] (3) Take 4g of N obtained in step (2) 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 79.1 mL of the 0.2 mol / L methyltrioctylammonium hydroxide solution obtained in step (1) was placed in a flask and stirred at 50 °C for 2 h. After the reaction was completed, it was cooled to room temperature, and the solvent was distilled under reduced pressure to obtain the triazolotetrazine energetic plasticizer [methyltrioctylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine], denoted as TOMA-DTOZ.

[0085] The resulting triazolotetraazine energetic plasticizer [methyltrioctylammonium][N 6 The proton, carbon, and infrared spectra of [-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetraazine] were analyzed, and the results are as follows: 1 H NMR (600 MHz, DMSO-d6): δ (ppm) = 9.52 (s, 1H), 3.22–3.13 (m, 12H), 2.93 (s, 6H), 1.60 (q, 12H), 1.32–1.22 (m, 60H), 0.86 (t, 18H). 13 C NMR (151 MHz, DMSO-d6) δ (ppm) = 153.67, 149.82, 149.69, 136.83, 116.15, 116.11, 60.53,47.52, 31.15, 28.45, 28.43, 28.38, 25.76, 22.05, 21.31, 13.94. IR γ (cm - ¹):3205, 2927, 2856, 2218, 1598, 1554, 1489, 1458, 1309, 1029, 956, 729.

[0086] From nuclear magnetic resonance hydrogen spectrum ( Figure 11 ), carbon spectrum ( Figure 12 ) and infrared spectrum ( Figure 13 It can be determined that the obtained black ionic liquid is the target product [methyltrioctylammonium][N] 6-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] and the structure of the target product is as follows:

[0087]

[0088] The obtained [methyltrioctylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] was subjected to DSC test, see Figure 14 and 15 , the glass transition temperature is -25.4℃, and the decomposition temperature is 172.7℃. Using Gaussian 09 software, the standard molar enthalpy of formation of [methyltrioctylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] is 444.2kJ / mol. The impact sensitivity of [methyltrioctylammonium][N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine] is >50J, and the friction sensitivity is >360N.

[0089] Application Example 1

[0090] A propellant comprising the following mass fractions of raw materials:

[0091] glycidyl azide polymer (GAP) 8%, ammonium perchlorate (AP) 50%, aluminum (Al) 18%, hexanitrohexaazaisowurtzitane (CL-20) 10%, and DODA-DTOZ obtained in Example 1 14%.

[0092] Application Example 2

[0093] A propellant comprising the following mass fractions of raw materials:

[0094] glycidyl azide polymer (GAP) 8%, ammonium perchlorate (AP) 50%, aluminum (Al) 18%, hexanitrohexaazaisowurtzitane (CL-20) 10%, and DODA-DTOZ obtained in Example 2 14%.

[0095] Application Example 3

[0096] A propellant comprising the following mass fractions of raw materials:

[0097] Glycidyl azide polymer (GAP) 8%, ammonium perchlorate (AP) 50%, aluminum (Al) 18%, hexanitrohexaazaisowurtzitane (CL-20) 10%, and TOMA-DTOZ obtained in Example 3 14%.

[0098] Comparative Application Example 1

[0099] The difference from Application Example 1 is that the DODA-DTOZ obtained in Example 1 is replaced by an equal mass of nitroglycerin (NG).

[0100] Comparative Application Example 2

[0101] The difference from Application Example 1 is that the DODA-DTOZ obtained in Example 1 is replaced by an equal mass of diisooctyl sebacate (DOS).

[0102] Technical effects:

[0103] The specific impulse (Isp) of the propellants obtained in Application Examples 1-3 and Comparative Application Examples 1-2 was calculated using CpropepShell software (combustion chamber pressure set to 7000 kPa, nozzle exit pressure set to 1 atm), and the results are shown in Table 1. Figure 16

[0104] It can be seen that the theoretical specific impulse values of the propellants obtained in Application Examples 1-3 are 267.7 s, 266.9 s and 266.7 s, respectively, which are significantly better than those of the traditional sensitive plasticizer NG (262.8 s) and the inert plasticizer DOS (261.4 s). The N 6 The triazolotetrazine-based energetic ionic liquid with a n-(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine anion has the characteristics of high energy and low sensitivity compared with traditional energetic materials, and the reaction conditions and environment are simple, the raw materials are easy to obtain, the product yield is high, the yield can reach more than 80%, and it is conducive to the large-scale synthesis and application of energetic materials.

[0105] The above merely describes preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any changes or replacements easily thought of by those skilled in the art within the technical scope disclosed by the present application should be encompassed within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.​

Claims

1. A triazolotetrazine-based energetic ionic liquid, characterized in that The structure is shown as formula (I): （I）； wherein R1, R2, R3, R4are each independently selected from -C n H n+2 .

2. The triazolotetrazinium energetic ionic liquid according to claim 1, characterized in that The triazolotetrazine energetic ionic liquid comprises the following structure: 。 3. A process for the preparation of triazolotetrazinium energetic ionic liquids according to claim 1, characterized in that, The method comprises the following steps: N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine and fatty quaternary ammonium base mixed heating reaction, after the reaction, remove the solvent, dry, to obtain the triazolotetrazine class of energetic ionic liquid.

4. The preparation method according to claim 2, characterized in that, The temperature of the heating reaction is 20-50℃, and the time is 0.5-2h; and / or, The N 6 The molar ratio of the (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazine to the fatty quaternary ammonium base is 1 : (1 -2).

5. The preparation method according to claim 2, characterized in that, The N 6 A process for the preparation of (1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazines comprising the steps of: After mixing 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3- b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine, catalyst and solvent, the reaction is carried out under heating, after which the reaction is worked up to give the N 6 -(1,3,4-oxadiazol-2-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine.

6. The production method according to claim 5, wherein The catalyst is selected from one or more of cesium carbonate, potassium carbonate, sodium carbonate and triethylamine; and / or, The solvent is selected from one or more of acetonitrile, methanol, ethanol, dioxane or N,N-dimethylformamide.

7. The preparation method according to claim 5, characterized in that, The molar ratio of the 6-(3,5-dimethyl-pyrazol-1-yl)-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine, 1,3,4-oxadiazol-2-amine and catalyst is 1:(1-2):(0.5-2).

8. The preparation method according to claim 5, characterized in that, The temperature of the reaction is 50-120℃, and the time is 2-12h.

9. The preparation method according to claim 2, characterized in that, The fatty quaternary ammonium base is obtained by anion exchange of a fatty quaternary ammonium salt; The fatty quaternary ammonium salt is selected from one of methyltrioctylammonium chloride, dipaulyldimethylammonium chloride or dioctyldimethylammonium chloride.

10. Application of the triazolotetrazine energetic ionic liquid of claim 1 in a solid propellant.

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