A method for preparing high-burning TATB-based aluminum-containing microspheres based on a Pickering emulsion method

Abstract

The application discloses a method for preparing high-combustion TATB-based aluminum-containing microspheres based on a Pickering emulsion method, and comprises the following steps: mixing and stirring solvent A and solvent B to obtain a mixed solvent; adding TATB into the mixed solvent to make the TATB completely dissolved, and taking the system after stabilization as a discontinuous phase of an emulsion; then adding nano-aluminum powder and a continuous phase, and uniformly mixing to obtain an emulsion system; and performing extraction treatment on the emulsion system to obtain the high-combustion TATB-based aluminum-containing microspheres. The method is simple, and different proportions of TATB-based aluminum-containing microspheres can be prepared by adjusting the addition amount of aluminum powder. The obtained microspheres have a particle size of about 90 microns, the crystal structure is unchanged, the thermal decomposition peak temperature is 24.9 DEG C earlier than that of raw material TATB, the reaction activity and combustion performance are significantly improved, and the mechanical sensitivity does not change obviously, and excellent insensitivity characteristics are maintained. The application provides a new method for optimizing the performance of submicron TATB, and lays a new direction for the modification, preparation and application expansion of energetic materials.

Description

Technical Field

[0001] This invention belongs to the field of energetic materials technology. More specifically, this invention relates to a method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method. Background Technology

[0002] 1,3,5-Triamino-2,4,6-Tinitrobenzene (TATB) is a high-energy, insensitive explosive with excellent heat resistance and safety properties, widely used in weapons, ammunition, and propellants. However, TATB is rich in carbon (molecular structure: C6H6N6O6), which easily produces a large amount of smoke upon ignition. This severely affects the combustion reaction of TATB, leading to incomplete combustion and thus reducing its combustion performance. Therefore, improving the combustion performance of TATB is of great significance for enhancing the overall performance of TATB-based energetic materials. Studies have shown that the energy characteristics of energetic materials can be improved by compositing them, and metal powder, as a high-energy material, can not only increase the energy density of energetic materials and provide more heat and active intermediates during ignition, but also act as a combustion catalyst or reducing agent to improve the combustion performance of elemental energetic materials. For example, Feng Xiaojun et al. improved the combustion performance of CL-20 by incorporating CL-20 / Al into a microstructure to promote the reaction of Al powder in the detonation zone, increasing the heat of explosion to 6930 J and the explosion field temperature inside the explosive container to 661.2 °C. Therefore, selecting a suitable process to prepare TATB-based metal-containing microspheres is of great significance in order to further improve the comprehensive performance of TATB-type energetic materials. Currently, there are two main categories of technologies for converting explosive crystals into spherical shapes: physical and chemical. Methods for combining energetic materials with metal powders include mechanical mixing, core-shell structures, metal embedding, and other composite methods. However, due to the irregular crystal structure of TATB raw materials and the low solubility and high cost of solvents, physical mixing leads to uneven product mixing and unstable product performance. Using core-shell structures requires overcoming the TATB solubility problem, as well as issues related to product shape and size. Metal embedding presents significant challenges for industrial production due to raw material characteristics and manufacturing processes. Therefore, promoting the industrial production of TATB-based metal-containing microspheres requires finding a rapid, efficient, and safe preparation method.

[0003] Guo Changping et al. constructed a spherical, flattened core-shell CL-20 / TNT eutectic@Al composite based on Pickering emulsion (Energetic Materials, 2022, 30(05): 483-490). Zhai Heng et al. prepared a zero-oxygen-equilibrium CL-20 / AP composite energetic material using the emulsion method (Journal of Explosives and Pyrotechnics, 2018, 41(01): 41-46). Hou Conghua et al. prepared a TATB / HMX-based composite microsphere using Pickering emulsion polymerization (Journal of Explosives and Pyrotechnics, 2024, 47(02): 145-151). The thermal and mechanical safety of the prepared composite microspheres were greatly improved.

[0004] While these literature reports have successfully prepared composite energetic materials using raw materials and experimental methods, a technological gap remains in the field of micron-scale composites of metal powders and TATB due to issues such as TATB solubility. Therefore, designing and inventing a method for preparing high-combustion-performance TATB-based aluminum-containing microspheres using the Pickering emulsion method is urgently needed to address the technical challenges of improving the combustion performance of TATB-based energetic materials, resolving issues of inhomogeneity and unstable combustion performance in composite materials, and enhancing the quality of TATB-based energetic material products to meet the demands of industrial production. Summary of the Invention

[0005] 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.

[0006] To achieve these objectives and other advantages of the present invention, a method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method is provided, comprising the following steps: Step 1: Mix solvent A and solvent B and stir to obtain a mixed solvent; Step 2: Dissolve TATB in a mixed solvent as the discontinuous phase of the emulsion, then add nano-aluminum powder and the continuous phase, and mix evenly to obtain the emulsion system. Step 3: Extract the emulsion system to obtain TATB-based aluminum-containing microspheres with high combustion performance.

[0007] Preferably, in step one, solvent A includes one or more of the following: dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, N-methylpyrrolidone, aniline, chloroform, ethyl acetate, butyl acetate, methanol, acetone, and butanone.

[0008] Preferably, in step one, solvent B comprises one or more of the following: 1-allyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium acetate, 1-alkyl-3-methylimidazolium propionate, 3-ethyl-1-methylimidazolium boron tetrafluoride, 3-butyl-1-methylimidazolium boron tetrafluoride, 3-butyl-1-methylimidazolium hexafluorophosphate, 3-ethyl-1-methylimidazolium bromide, 3-butyl-1-methylimidazolium chloride, methylimidazolium butyrate acetate, alkyl ammonium fluoride, N-methylmorpholine-N-oxide, and zinc chloride.

[0009] Preferably, in step one, the mass ratio of solvent A to solvent B is 1:100 to 100:1.

[0010] Preferably, in step two, the mass-to-volume ratio of TATB to the mixed solvent is 0.1 g: 1~20 mL.

[0011] Preferably, in step two, the amount of nano-aluminum powder added is 1% to 20% of the mass of TATB.

[0012] Preferably, in step two, the continuous phase includes one or more of the following: cyclohexane, n-octane, xylene, dipropyl ether, pentane, isooctane, n-hexane, and n-heptane.

[0013] Preferably, in step two, the volume ratio of the continuous phase to the discontinuous phase is 1:10 to 10:1.

[0014] Preferably, in step three, the specific method of extraction is as follows: non-solvent is added to the emulsion system by dripping or spraying to extract the emulsion, so that the non-solvent gradually diffuses into the emulsion, precipitating TATB-based aluminum-containing microspheres, followed by filtration, washing, and drying.

[0015] Preferably, the non-solvent includes one or more of water, ethanol, ethyl acetate, dimethylformamide, and methanol; the washing reagent includes one or more of distilled water, ethanol, dimethyl sulfoxide, and ethyl acetate; and the drying method is one of room temperature drying, vacuum drying, and freeze drying.

[0016] Preferably, in step two, the nano-aluminum powder is modified before use to obtain modified nano-aluminum powder.

[0017] Preferably, the preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse the nano-aluminum powder in cyclohexane, and add ethyl acetate containing Tween-80 dropwise under stirring. After the addition is complete, continue stirring, centrifuge, wash, and dry to obtain pretreated nano-aluminum powder. S2. Add tannic acid and polyvinylpyrrolidone to Tris-HCl buffer solution and stir until homogeneous to obtain mixture A; disperse pretreated nano-aluminum powder in deionized water to obtain mixture B; mix mixture A and mixture B, sonicate, let stand, centrifuge, wash and dry to obtain primary modified nano-aluminum powder; S3. Disperse the modified nano-aluminum powder into anhydrous ethanol, add polyethylene glycol, and add cyclohexane dropwise while stirring. After the addition is complete, continue stirring, centrifuge, wash, and dry to obtain the modified nano-aluminum powder.

[0018] Preferably, in S1, the mass-to-volume ratio of nano-aluminum powder to cyclohexane is 1g:10~30mL; the mass-to-volume ratio of Tween-80 to ethyl acetate is 0.1g:30~70mL; the mass ratio of nano-aluminum powder to Tween-80 is 10:0.05~0.5; the dropping rate is 1~10mL / min; and stirring continues for 20~50min after the dropping is completed.

[0019] Preferably, in step S2, the concentration of the Tris-HCl buffer solution is 1~30mM, and the pH is 8~9; the mass-to-volume ratio of tannic acid, polyvinylpyrrolidone, and Tris-HCl buffer solution is 0.1~0.5g:0.05~0.2:50~200mL; the mass-to-volume ratio of pretreated nano-aluminum powder and deionized water is 1g:5~20mL; the mass ratio of tannic acid and pretreated nano-aluminum powder is 0.1~0.5:5~15; the ultrasonic treatment lasts for 0.5~2h, followed by standing for 4~8h; the ultrasonic power is 200~500W, and the ultrasonic frequency is 40~70kHz.

[0020] Preferably, in step S3, the mass-to-volume ratio of the primary modified nano-aluminum powder, polyethylene glycol, anhydrous ethanol, and cyclohexane is 5-15 g: 0.05-0.2 g: 50-200 mL: 100-300 mL; the dropping rate is 1-10 mL / min; and stirring continues for 20-50 min after the dropping is completed.

[0021] The present invention has at least the following beneficial effects: (1) The TATB-based aluminum-containing microspheres prepared by the present invention have a particle size of about 90 μm, and their crystal structure has not changed. The thermal decomposition performance is 24.9 °C earlier than that of the raw material, there is no shoulder peak, and the heat release of thermal decomposition is more concentrated. At the same time, the TATB-based aluminum-containing microspheres prepared by the present invention have excellent combustion performance, shorter combustion time, and more stable combustion.

[0022] (2) In this invention, nano-sized aluminum powder is used as a surfactant to prepare TATB-based aluminum-containing microspheres, which further enables the nano-aluminum powder and TATB crystals in the TATB / Al composite microspheres to come into interfacial contact at the submicron scale, and the influence of nano-aluminum powder on the thermal decomposition process of TATB is more significant.

[0023] (3) The present invention further modifies the nano-aluminum powder. First, Tween-80 is used to pretreat the surface of the nano-aluminum powder to improve its dispersibility, avoid raw material agglomeration, improve surface reactivity, and facilitate subsequent reactions. Then, polyvinylpyrrolidone and tannic acid are used to perform a first modification treatment on the pretreated nano-aluminum powder to increase active sites and improve combustion performance. Finally, polyethylene glycol is used for a second modification treatment to further improve its dispersibility and surface activity, which is conducive to sufficient contact and uniform mixing with TATB in the subsequent process. The present invention has a synergistic effect through pretreatment-first modification-second modification. That is, it can effectively avoid the oxidation and deactivation of nano-aluminum powder, improve its combustion performance, improve the dispersibility of nano-aluminum powder in microspheres, promote more uniform mixing of nano-aluminum powder and TATB, regulate the interfacial contact between nano-aluminum powder and TATB, and make the contact more sufficient and tight. In addition, it is also conducive to improving the stability and uniformity of the emulsion system. The TATB-based aluminum-containing microspheres prepared by the modified nano-aluminum powder are more uniform and stable, have better combustion performance, and excellent safety performance.

[0024] (4) The mechanical sensitivity of the TATB-based aluminum microspheres prepared by the present invention did not change significantly and remained very insensitive to external mechanical stimuli. The impact sensitivity was tested by a drop hammer, with a maximum height of 120 cm. The TATB-based aluminum microspheres did not explode. Similarly, no explosion occurred in the friction sensitivity test.

[0025] 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

[0026] Figure 1 (a) is a SEM image of the raw material TATB. Figure 1 (b) An optical microscope image of the TATB-based aluminum-containing microspheres prepared in Example 1. Figure 1 (c) and Figure 1 (d) is a SEM image of the TATB-based aluminum-containing microspheres prepared in Example 1; Figure 2 XRD patterns of TATB-based aluminum-containing microspheres prepared in Example 1 of the present invention, TATB / Al mixture prepared in Comparative Example 1, and raw material TATB; Figure 3FT-IR images of TATB-based aluminum-containing microspheres prepared in Example 1 of the present invention, the TATB / Al mixture prepared in Comparative Example 1, and the raw material TATB; Figure 4 The images show DSC diagrams of TATB-based aluminum-containing microspheres prepared in Examples 1, 6, and 8 of this invention, the TATB / Al mixture prepared in Comparative Example 1, the TATB microspheres prepared in Comparative Example 2, and the raw material TATB. Figure 5 Ignition test diagrams of (a) the TATB / Al mixture prepared in Comparative Example 1, (b) the TATB-based aluminum microspheres prepared in Example 1, (c) the TATB-based aluminum microspheres prepared in Example 6, and (d) the TATB-based aluminum microspheres prepared in Example 8. Detailed Implementation

[0027] 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.

[0028] 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.

[0029] Example 1 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium hexafluorophosphate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to dissolve TATB completely. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.005 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Slowly add anhydrous ethanol to the emulsion system via spray extraction to allow the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum microspheres remain spherical and gradually precipitate out. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum microspheres are obtained.

[0030] Example 2 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium chloride at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.006 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Slowly add anhydrous ethanol to the emulsion system via spray extraction to allow the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum microspheres remain spherical and gradually precipitate out. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum microspheres are obtained.

[0031] Example 3 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium acetate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.007 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Slowly add anhydrous ethanol to the emulsion system via spray extraction to allow the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum microspheres remain spherical and gradually precipitate out. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum microspheres are obtained.

[0032] Example 4 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-ethyl-3-methylimidazolium acetate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to dissolve TATB completely. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.008 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Slowly add anhydrous ethanol to the emulsion system via spray extraction to allow the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum microspheres remain spherical and gradually precipitate out. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum microspheres are obtained.

[0033] Example 5 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium hexafluorophosphate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use this as the discontinuous phase of the emulsion. Then add 0.009 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Extraction is carried out by slowly adding anhydrous ethanol to the emulsion system via spraying, allowing the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum-containing microspheres are gradually precipitated while maintaining their spherical shape. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum-containing microspheres are obtained. Compared to Example 1, the amount of nano-aluminum powder used in this example is 9% of TATB.

[0034] Example 6 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium hexafluorophosphate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.01 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Extraction is carried out by slowly adding anhydrous ethanol to the emulsion system via spraying, allowing the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum-containing microspheres are gradually precipitated while maintaining their spherical shape. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum-containing microspheres are obtained. Compared to Example 1, the amount of nano-aluminum powder used in this example is 10% of TATB.

[0035] Example 7 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium hexafluorophosphate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.011 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Extraction is carried out by slowly adding anhydrous ethanol to the emulsion system via spraying, allowing the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum-containing microspheres are gradually precipitated while maintaining their spherical shape. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum-containing microspheres are obtained. Compared to Example 1, the amount of nano-aluminum powder used in this example is 11% of TATB.

[0036] Example 8 A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method includes the following steps: Step 1: Mix dimethyl sulfoxide and 1-butyl-3-methylimidazolium hexafluorophosphate at a mass ratio of 2:1 to obtain a mixed solvent; Step 2: Add 0.1 g of TATB to 10 mL of mixed solvent and sonicate to completely dissolve the TATB. After stabilization, use it as the discontinuous phase of the emulsion. Then add 0.015 g of nano-Al powder and 10 mL of n-octane and sonicate to mix evenly to obtain the emulsion system. The sonication power is 300 W and the sonication frequency is 55 kHz. Step 3: Extraction is carried out by slowly adding anhydrous ethanol to the emulsion system via spraying, allowing the ethanol to gradually diffuse into the emulsion. The TATB-based aluminum-containing microspheres are gradually precipitated while maintaining their spherical shape. After filtration, washing with ethanol, and vacuum drying, high-combustion-performance TATB-based aluminum-containing microspheres are obtained. Compared to Example 1, the amount of nano-aluminum powder used in this example is 15% of TATB.

[0037] Example 9 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse 10 g of nano-aluminum powder into 200 mL of cyclohexane. Under stirring at 200 rpm, add 50 mL of ethyl acetate containing 0.1 g of Tween-80 dropwise at a rate of 2 mL / min. After the addition is complete, continue stirring for 30 min. Centrifuge, wash, and vacuum dry to obtain pretreated nano-aluminum powder. S2. Add 0.3 g of tannic acid and 0.1 g of polyvinylpyrrolidone to 100 mL of 10 mM Tris-HCl buffer solution (pH=8.5) and stir until homogeneous to obtain mixture A; add 10 g of pretreated nano-aluminum powder to 100 mL of deionized water and disperse by ultrasonication to obtain mixture B; mix mixture A and mixture B, sonicate for 1 h, let stand for 6 h, centrifuge, wash, and vacuum dry to obtain primary modified nano-aluminum powder; wherein, the ultrasonic power is 300 W and the ultrasonic frequency is 55 kHz; S3. Disperse 10 g of one-time modified nano-aluminum powder into 100 mL of anhydrous ethanol, add 0.1 g of polyethylene glycol 2000, and add 200 mL of cyclohexane dropwise at a rate of 5 mL / min while stirring at 200 rpm. After the addition is complete, continue stirring for 30 min, centrifuge, wash, and vacuum dry to obtain modified nano-aluminum powder.

[0038] Example 10 In this embodiment, pretreated nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8. The preparation method of the pretreated nano-aluminum powder includes the following steps: 10 g of nano-aluminum powder is dispersed in 200 mL of cyclohexane, and 50 mL of ethyl acetate containing 0.1 g of Tween-80 is added dropwise at a rate of 2 mL / min under stirring at 200 rpm. After the addition is completed, stirring is continued for 30 min. The powder is then centrifuged, washed, and vacuum dried to obtain the pretreated nano-aluminum powder. Compared to Example 9, the pretreated nano-aluminum powder in this example does not undergo the modification treatment steps S2 and S3.

[0039] Example 11 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the primary modified nano-aluminum powder includes the following steps: S1. Disperse 10 g of nano-aluminum powder into 200 mL of cyclohexane. Under stirring at 200 rpm, add 50 mL of ethyl acetate containing 0.1 g of Tween-80 dropwise at a rate of 2 mL / min. After the addition is complete, continue stirring for 30 min. Centrifuge, wash, and vacuum dry to obtain pretreated nano-aluminum powder. S2. Add 0.3 g of tannic acid and 0.1 g of polyvinylpyrrolidone to 100 mL of 10 mM Tris-HCl buffer solution (pH=8.5) and stir until homogeneous to obtain mixture A; add 10 g of pretreated nano-aluminum powder to 100 mL of deionized water and disperse by ultrasonication to obtain mixture B; mix mixture A and mixture B, sonicate for 1 h, let stand for 6 h, centrifuge, wash, and vacuum dry to obtain primary modified nano-aluminum powder; wherein, the ultrasonic power is 300 W and the ultrasonic frequency is 55 kHz; Compared to Example 9, the modified nano-aluminum powder in this example does not undergo the modification process S3.

[0040] Example 12 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse 10 g of nano-aluminum powder into 200 mL of cyclohexane. Under stirring at 200 rpm, add 50 mL of ethyl acetate containing 0.1 g of Tween-80 dropwise at a rate of 2 mL / min. After the addition is complete, continue stirring for 30 min. Centrifuge, wash, and vacuum dry to obtain pretreated nano-aluminum powder. S2. Disperse 10 g of pretreated nano-aluminum powder into 100 mL of anhydrous ethanol, add 0.1 g of polyethylene glycol 2000, and add 200 mL of cyclohexane dropwise at a rate of 5 mL / min while stirring at 200 rpm. After the addition is complete, continue stirring for 30 min, centrifuge, wash, and vacuum dry to obtain modified nano-aluminum powder. Compared to Example 9, the modified nano-aluminum powder preparation method in this example does not include the S2 modification step.

[0041] Example 13 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the modified nano-aluminum powder includes the following steps: S1. Add 0.3 g of tannic acid and 0.1 g of polyvinylpyrrolidone to 100 mL of 10 mM Tris-HCl buffer solution (pH=8.5) and stir until homogeneous to obtain mixture A; add 10 g of nano-aluminum powder to 100 mL of deionized water and disperse by ultrasonication to obtain mixture B; mix mixture A and mixture B, sonicate for 1 h, let stand for 6 h, centrifuge, wash, and vacuum dry to obtain primary modified nano-aluminum powder; wherein, the ultrasonic power is 300 W and the ultrasonic frequency is 55 kHz; S2. Disperse 10 g of one-time modified nano-aluminum powder into 100 mL of anhydrous ethanol, add 0.1 g of polyethylene glycol 2000, and add 200 mL of cyclohexane dropwise at a rate of 5 mL / min while stirring at 200 rpm. After the addition is complete, continue stirring for 30 min, centrifuge, wash, and vacuum dry to obtain modified nano-aluminum powder. Compared to Example 9, the preparation method of modified nano-aluminum powder in this example does not include the pretreatment step S1.

[0042] Example 14 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse 10 g of nano-aluminum powder into 200 mL of cyclohexane. Under stirring at 200 rpm, add 50 mL of ethyl acetate containing 0.1 g of Tween-80 dropwise at a rate of 2 mL / min. After the addition is complete, continue stirring for 30 min. Centrifuge, wash, and vacuum dry to obtain pretreated nano-aluminum powder. S2. Add 0.3 g of tannic acid to 100 mL of 10 mM Tris-HCl buffer solution (pH=8.5) and stir until homogeneous to obtain mixture A; add 10 g of pretreated nano-aluminum powder to 100 mL of deionized water and disperse by ultrasonication to obtain mixture B; mix mixture A and mixture B, sonicate for 1 h, let stand for 6 h, centrifuge, wash, and vacuum dry to obtain primary modified nano-aluminum powder; wherein, the ultrasonic power is 300 W and the ultrasonic frequency is 55 kHz; S3. Disperse 10 g of one-time modified nano-aluminum powder into 100 mL of anhydrous ethanol, add 0.1 g of polyethylene glycol 2000, and add 200 mL of cyclohexane dropwise at a rate of 5 mL / min while stirring at 200 rpm. After the addition is complete, continue stirring for 30 min, centrifuge, wash, and vacuum dry to obtain modified nano-aluminum powder. Compared to Example 9, in the preparation method of modified nano-aluminum powder in this example, step S2 does not use polyvinylpyrrolidone.

[0043] Example 15 In this embodiment, modified nano-aluminum powder is used to replace nano-aluminum powder, and the remaining steps are the same as in Example 8; The preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse 10 g of nano-aluminum powder into 200 mL of cyclohexane. Under stirring at 200 rpm, add 50 mL of ethyl acetate containing 0.1 g of Tween-80 dropwise at a rate of 2 mL / min. After the addition is complete, continue stirring for 30 min. Centrifuge, wash, and vacuum dry to obtain pretreated nano-aluminum powder. S2. Add 0.1 g of polyvinylpyrrolidone to 100 mL of 10 mM Tris-HCl buffer solution (pH=8.5) and stir until homogeneous to obtain mixture A; add 10 g of pretreated nano-aluminum powder to 100 mL of deionized water and disperse by ultrasonication to obtain mixture B; mix mixture A and mixture B, sonicate for 1 h, let stand for 6 h, centrifuge, wash, and vacuum dry to obtain primary modified nano-aluminum powder; wherein, the ultrasonic power is 300 W and the ultrasonic frequency is 55 kHz; S3. Disperse 10 g of one-time modified nano-aluminum powder into 100 mL of anhydrous ethanol, add 0.1 g of polyethylene glycol 2000, and add 200 mL of cyclohexane dropwise at a rate of 5 mL / min while stirring at 200 rpm. After the addition is complete, continue stirring for 30 min, centrifuge, wash, and vacuum dry to obtain modified nano-aluminum powder. Compared to Example 9, in the preparation method of modified nano-aluminum powder in this example, tannic acid is not used in step S2.

[0044] Comparative Example 1 A method for preparing TATB / Al with enhanced combustion performance through conventional physical mixing includes the following steps: Step 1: Pre-treat the nano-aluminum powder and spherical TATB to ensure particle dispersibility and prevent large pieces of material from affecting the uniformity of mixing; Step 2: Add 0.05 g of nano aluminum powder and 0.5 g of spherical TATB into a mortar and grind slowly by hand, mixing multiple times with uniform force to avoid violent friction and ensure even distribution of materials. Step 3: The mixture is sieved to obtain a mixed TATB / Al sample.

[0045] Comparative Example 2 This comparative example does not add nano-Al powder, and the remaining steps are the same as in Example 1 to obtain TATB microspheres.

[0046] Figure 1 (a) SEM image of the raw material TATB, (b) optical microscope image of the TATB-based aluminum-containing microspheres prepared in Example 1, and (c) and (d) SEM images of the TATB-based aluminum-containing microspheres prepared in Example 1. Figure 1 As can be seen in (a), the raw material TATB is irregular TATB with a particle size of approximately 20 μm; Figure 1(b) The TATB-based aluminum-containing microspheres prepared in Example 1 exhibit a regular spherical structure. Further electron microscopy images (c and d) also show that the TATB-based aluminum-containing microspheres prepared in Example 1 have a spherical structure and a particle size of approximately 90 μm.

[0047] Figure 2 The XRD patterns of the TATB-based aluminum-containing microspheres (TATB / Al microspheres) prepared in Example 1, the mixed TATB / Al prepared in Comparative Example 1, and the raw TATB are shown. It can be seen that the characteristic diffraction peaks of the raw TATB at 11.62°, 19.72°, 28.36°, and 42.18° correspond to the (1,1,0), (2,1,0), (0,0,2), and (2,2,0) crystal planes of TATB, respectively. The characteristic diffraction peaks of the TATB / Al microspheres prepared by the emulsion method are basically coincident with those of the raw TATB, indicating that the crystal form of the TATB / Al microspheres has not changed. Meanwhile, characteristic diffraction peaks of Al powder were observed at 38.44°, 44.72°, and 65.08° in TATB / Al microspheres and mixed TATB / Al samples, indicating that TATB and Al powder were successfully composited. In addition, the diffraction peaks of TATB / Al microspheres were significantly broadened, which may be due to the recrystallization process of the emulsion method changing the crystal size of TATB, thus exhibiting the characteristic X-ray diffraction of typical nanoparticles.

[0048] Figure 3 The FT-IR spectra of TATB-based aluminum-containing microspheres (TATB / Al microspheres) prepared in Example 1, the mixed TATB / Al prepared in Comparative Example 1, and the raw material TATB are shown. As can be seen from the figure, the characteristic peaks of the obtained materials are basically consistent with those of the raw material TATB; this indicates that all products are TATB, and no crystallization byproducts were detected; the characteristic absorption peak of the raw material TATB appears at 3315.5 cm⁻¹. -1 and 3211.3 cm -1 1616.3 cm -1 and 1442.7 cm -1 1220.9 cm -1 and 1176.5 cm -1 The peaks correspond to the asymmetric and symmetric stretching vibrations of -NH3, the vibrational absorption peaks of the –C≡C– skeleton on the benzene ring, and the stretching vibration absorption peaks of –NO2, respectively. The FT-IR spectra of TATB / Al microspheres are basically consistent with the characteristic diffraction peak positions of the FT-IR spectra of the raw material TATB, indicating that the TATB / Al microspheres prepared by the emulsion method only changed the morphology and size of TATB, while its structure and crystal form remained unchanged.

[0049] Figure 4The figures show the DSC spectra of TATB-based aluminum-containing microspheres prepared in Examples 1, 6, and 8, the TATB / Al mixture prepared in Comparative Example 1, the TATB microspheres prepared in Comparative Example 2, and the raw TATB. The figures show that the thermal decomposition peak temperature of the raw TATB is 374.9℃, with a distinct shoulder peak at 363.6℃; the thermal decomposition peak temperature of the TATB / Al mixture prepared in Comparative Example 1 is 374.0℃, with a distinct shoulder peak at 363.8℃; while the pure TATB microspheres prepared in Comparative Example 2 only have an exothermic decomposition peak at 371.5℃, indicating that the microsphere structure can improve the shoulder peak problem of TATB, making the exothermic effect more concentrated. Furthermore, the exothermic decomposition peak of the TATB-based aluminum-containing microspheres prepared in Example 1 is slightly earlier than that of the pure TATB microspheres prepared in Comparative Example 2. As the Al powder content increases, the phenomenon of earlier thermal decomposition becomes more obvious. For example, the TATB-based aluminum microspheres prepared in Example 8 showed that the exothermic decomposition peak was 21.5 °C earlier than that of Comparative Example 2 and 24.9 °C earlier than that of the raw material TATB. This indicates that Al powder has good catalytic performance in TATB microspheres and there are no shoulder peaks. The thermal decomposition is more concentrated, which may be because the TATB crystals in TATB / Al microspheres have sufficient interfacial contact with nano-Al powder at the submicron scale.

[0050] Figure 5 The images show the ignition and combustion of the TATB / Al mixture prepared in Comparative Example 1(a) and the TATB-based aluminum-containing microspheres prepared in Examples 1(b), 6(c), and 8(d). The raw material TATB and the pure TATB microspheres prepared in Comparative Example 2 could not be ignited. As can be seen from the images, the combustion phenomenon in Comparative Example 1 exhibits an unstable combustion process with an unstable flame that initially increases in size, then decreases, and finally continues to burn slowly. The combustion time is as long as 5376 ms, which may be due to the difficulty in achieving a uniform submicron-scale mixing of TATB and Al. The TATB-based aluminum-containing microspheres prepared in Example 1 show a relatively stable combustion flame with a slightly shorter combustion time, indicating that the uniform microsphere structure and Al powder are beneficial for improving the combustion characteristics of TATB. In contrast, the TATB-based aluminum-containing microspheres prepared in Examples 6 and 8 show a significantly shorter combustion time, as low as 680 ms, and a significantly larger flame with more complete combustion. This is because the increased Al powder content provides good catalytic performance for the microsphere-structured TATB, which is consistent with the conclusions drawn from the DSC data.

[0051] The nano-aluminum powder was modified. The combustion times of Examples 9-15 were 382 ms, 635 ms, 467 ms, 522 ms, 440 ms, 408 ms, and 433 ms, respectively, and the combustion was stable with clear flame edges. Among them, the TATB-based aluminum-containing microspheres prepared in Example 9 had the best combustion performance, with a combustion time as low as 382 ms, indicating faster and more complete combustion. Furthermore, it only had one exothermic decomposition peak at 343.7 °C, without any shoulder peak. The exothermic decomposition peak was earlier than that of the TATB-based aluminum-containing microspheres in Example 8 (350 °C), indicating that the modified nano-aluminum powder still possesses good catalytic performance in the TATB microspheres, with more concentrated thermal decomposition.

[0052] The mechanical sensitivity of the TATB-based aluminum-containing microspheres prepared in Examples 1-15 of this invention did not change significantly, and they remained very insensitive to external mechanical stimuli. When the impact sensitivity was tested by a drop hammer at a maximum height of 120 cm, none of the TATB-based aluminum-containing microspheres exploded. Similarly, no explosions occurred in the friction sensitivity test.

[0053] 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. A method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method, characterized in that, Includes the following steps: Step 1: Mix solvent A and solvent B and stir to obtain a mixed solvent; Step 2: Dissolve TATB in a mixed solvent as the discontinuous phase of the emulsion, then add nano-aluminum powder and the continuous phase, and mix evenly to obtain the emulsion system. Step 3: Extract the emulsion system to obtain TATB-based aluminum-containing microspheres with high combustion performance.

2. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 1, characterized in that, In step one, solvent A includes one or more of the following: dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, N-methylpyrrolidone, aniline, chloroform, ethyl acetate, butyl acetate, methanol, acetone, and butanone; Solvent B includes one or more of the following: 1-allyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium acetate, 1-alkyl-3-methylimidazolium propionate, 3-ethyl-1-methylimidazolium boron tetrafluoride, 3-butyl-1-methylimidazolium boron tetrafluoride, 3-butyl-1-methylimidazolium hexafluorophosphate, 3-ethyl-1-methylimidazolium bromide, 3-butyl-1-methylimidazolium chloride, methylimidazolium acetate butyrate, alkyl ammonium fluoride, N-methylmorpholine-N-oxide, and zinc chloride; The mass ratio of solvent A to solvent B is 1:100 to 100:

1.

3. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 1, characterized in that, In step two, the mass-to-volume ratio of TATB to the mixed solvent is 0.1g:1~20mL; the amount of nano-aluminum powder added is 1%~20% of the mass of TATB.

4. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 1, characterized in that, In step two, the continuous phase includes one or more of cyclohexane, n-octane, xylene, dipropyl ether, pentane, isooctane, n-hexane, and n-heptane; the volume ratio of the continuous phase to the discontinuous phase is 1:10 to 10:

1.

5. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 1, characterized in that, In step three, the specific method of extraction is as follows: non-solvent is added to the emulsion system by dripping or spraying to extract the emulsion, so that the non-solvent gradually diffuses into the emulsion and precipitates TATB-based aluminum-containing microspheres, followed by filtration, washing, and drying.

6. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 5, characterized in that, The non-solvent includes one or more of water, ethanol, ethyl acetate, dimethylformamide, and methanol; the washing reagent includes one or more of distilled water, ethanol, dimethyl sulfoxide, and ethyl acetate; the drying method is one of room temperature drying, vacuum drying, and freeze drying.

7. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 1, characterized in that, In step two, before using the nano-aluminum powder, the nano-aluminum powder is modified to obtain modified nano-aluminum powder. The preparation method of the modified nano-aluminum powder includes the following steps: S1. Disperse the nano-aluminum powder in cyclohexane, and add ethyl acetate containing Tween-80 dropwise under stirring. After the addition is complete, continue stirring, centrifuge, wash, and dry to obtain pretreated nano-aluminum powder. S2. Add tannic acid and polyvinylpyrrolidone to Tris-HCl buffer solution and stir until homogeneous to obtain mixture A; disperse pretreated nano-aluminum powder in deionized water to obtain mixture B; mix mixture A and mixture B, sonicate, let stand, centrifuge, wash and dry to obtain primary modified nano-aluminum powder; S3. Disperse the modified nano-aluminum powder into anhydrous ethanol, add polyethylene glycol, and add cyclohexane dropwise while stirring. After the addition is complete, continue stirring, centrifuge, wash, and dry to obtain the modified nano-aluminum powder.

8. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 7, characterized in that, In S1, the mass-to-volume ratio of nano-aluminum powder to cyclohexane is 1g:10~30mL; the mass-to-volume ratio of Tween-80 to ethyl acetate is 0.1g:30~70mL; the mass ratio of nano-aluminum powder to Tween-80 is 10:0.05~0.5; the dropping rate is 1~10mL / min, and stirring continues for 20~50min after the dropping is completed.

9. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 7, characterized in that, In step S2, the concentration of the Tris-HCl buffer solution is 1-30 mM, and the pH is 8-9; the mass-to-volume ratio of tannic acid, polyvinylpyrrolidone, and Tris-HCl buffer solution is 0.1-0.5 g: 0.05-0.2: 50-200 mL; the mass-to-volume ratio of pretreated nano-aluminum powder and deionized water is 1 g: 5-20 mL; the mass ratio of tannic acid and pretreated nano-aluminum powder is 0.1-0.5: 5-15; ultrasonic treatment is performed for 0.5-2 h, followed by standing for 4-8 h; the ultrasonic power is 200-500 W, and the ultrasonic frequency is 40-70 kHz.

10. The method for preparing high-combustion-performance TATB-based aluminum-containing microspheres based on the Pickering emulsion method as described in claim 7, characterized in that, In step S3, the mass-to-volume ratio of the primary modified nano-aluminum powder, polyethylene glycol, anhydrous ethanol, and cyclohexane is 5-15 g: 0.05-0.2 g: 50-200 mL: 100-300 mL; the dropping rate is 1-10 mL / min, and stirring continues for 20-50 min after the dropping is completed.

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