Spherical dihydroxy ethanedioxime, a preparation method thereof and an energetic material

Abstract

The embodiment of the present application provides a kind of spherical dihydroxy glyoxime and its preparation method and energetic material.The method comprises the following steps: hydrochloric acid solution and dihydroxy glyoxime metal salt suspension are simultaneously added into reaction bottom liquid containing regulator, crystallization reaction is carried out, and crystal suspension is obtained;The crystal suspension is filtered, and the spherical dihydroxy glyoxime is obtained.The method is used to achieve the effect of providing the flowability and bulk density of spherical dihydroxy glyoxime.

Description

Technical Field

[0001] This application relates to the field of energetic material preparation technology, specifically to a spherical dihydroxyethylenedioxime, its preparation method, and energetic material, which is particularly suitable for the large-scale production of sustained-release agents in rocket propellants. Background Technology

[0002] Spherical dihydroxyethylenedioxime (DHG, C2H4N2O4) is a high-performance sustained-release agent widely used in rocket propellants, energetic materials, pharmaceuticals, and fine chemicals. In rocket propellants, DHG significantly improves the stability and safety of the propellant by reducing the combustion rate and temperature. In energetic materials, its excellent solubility and thermal stability make it an ideal additive for high-energy materials. Furthermore, DHG can be used in the pharmaceutical field to synthesize specific drug intermediates and in the food industry as an antioxidant or stabilizer.

[0003] However, the morphological problems of existing DHG crystals (such as needle-like or plate-like structures) result in poor fluidity and low packing density, which severely restricts their application in the aforementioned fields.

[0004] Therefore, there is an urgent need to develop an efficient method for preparing spherical DHG to improve its flowability and packing density. Summary of the Invention

[0005] This application provides a spherical dihydroxyethylenedioxime, its preparation method, and an energetic material, which can improve the flowability and bulk density of the spherical dihydroxyethylenedioxime.

[0006] In a first aspect, embodiments of this application provide a method for preparing spherical dihydroxydioxime, comprising: simultaneously adding hydrochloric acid solution and dihydroxydioxime metal salt suspension to a reaction substrate containing a regulator, and carrying out a crystallization reaction to obtain a crystal suspension;

[0007] The crystal suspension was filtered to obtain the spherical dihydroxyethylenedioxime;

[0008] The regulator includes at least one of hydroxypropyl methylcellulose, polyethylene glycol, and sodium dodecyl sulfate.

[0009] In one possible implementation, the dihydroxydioxime metal salt comprises dihydroxydioxime sodium salt.

[0010] In one possible implementation, the number-average molecular weight of the hydroxypropyl methylcellulose is 10,000 g / mol to 1,500,000 g / mol.

[0011] In one possible implementation, the regulator accounts for 0.07%-0.09% by mass of the theoretical yield of the spherical dihydroxyethylenedioxime;

[0012] And / or, the hydrochloric acid solution has a mass fraction of 12.3%-15.2%;

[0013] And / or, the spherical dihydroxydioxime has a mass fraction of 12.9%-14.2% in the dihydroxydioxime metal salt suspension.

[0014] In one possible implementation, the simultaneous addition of hydrochloric acid solution and dihydroxyethylenedioxime metal salt suspension to the base solution includes:

[0015] The hydrochloric acid solution and the dihydroxyethylenedioxime metal salt suspension are simultaneously added to the base liquid using a dual-pipe feeding device;

[0016] Alternatively, the hydrochloric acid solution and the dihydroxyethylenedioxime metal salt suspension can be alternately added to the base solution using a pulse feeding device.

[0017] In one possible implementation, the volume ratio of the hydrochloric acid solution to the reaction substrate is 1:(2-6).

[0018] And / or, the volume ratio of the dihydroxydioxime metal salt suspension to the reaction substrate is 1:(1.0-1.5).

[0019] In one possible implementation, the temperature of the crystallization reaction is 45°C-55°C, and the time of the crystallization reaction is 0.5h-3h.

[0020] Secondly, embodiments of this application provide a spherical dihydroxyethylenedioxime, prepared by the above-described preparation method.

[0021] In one possible implementation, the aspect ratio of the spherical dihydroxydioxime is less than or equal to 1.5;

[0022] And / or, the SPAN of the spherical dihydroxydioxime is 1.0-1.2;

[0023] And / or, the tap density of the spherical dihydroxydioxime is greater than or equal to 0.8 g / cm³. 3 ;

[0024] And / or, the thermal decomposition temperature of the spherical dihydroxydioxime is greater than 170°C.

[0025] Thirdly, embodiments of this application provide an energetic material, including spherical dihydroxyethylenedioxime prepared by the above preparation method or the above spherical dihydroxyethylenedioxime.

[0026] This application provides a spherical dihydroxyethylenedioxime, its preparation method, and an energetic material. By simultaneously adding hydrochloric acid and a dihydroxyethylenedioxime metal salt suspension to a reaction substrate containing a regulator, the polymerization effect of the regulator causes the spherical dihydroxyethylenedioxime crystal nuclei to precipitate in a concentrated manner. A large number of crystals agglomerate into spheres and continue to grow on the spherical crystal sites. This effectively avoids the problem of crystal nuclei being too dispersed and difficult to aggregate into spheres, thus achieving the preparation of spherical dihydroxyethylenedioxime with excellent flowability and improving the flowability and packing density of spherical dihydroxyethylenedioxime. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0028] Figure 1 The PXRD spectra of the spherical dihydroxydioxime and the standard provided in this application;

[0029] Figure 2 The optical microscope image shows the morphology of the spherical dihydroxydioxime provided in this application.

[0030] Figure 3 Scanning electron morphology image of the spherical dihydroxyethyl oxime provided in this application;

[0031] Figure 4 A schematic diagram of the TG-DSC curve of the dihydroxyethylenedioxime metal salt provided in this application;

[0032] Figure 5 A schematic diagram of the TG-DSC curve of the spherical dihydroxyethyl oxime provided in this application;

[0033] Figure 6 A schematic diagram of the particle size distribution curve of the dihydroxyethylenedioxime metal salt provided in the application;

[0034] Figure 7 A schematic diagram of the particle size distribution curve of the spherical dihydroxyethylenedioxime provided in this application.

[0035] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0036] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0037] In the prior art, spherical dihydroxyethylene dioxime has technical problems such as poor flowability and low bulk density.

[0038] The method for preparing spherical dihydroxydioxime provided in this application solves the technical problems of poor flowability and low bulk density of spherical dihydroxydioxime by simultaneously adding hydrochloric acid and a suspension of spherical dihydroxydioxime to a reaction substrate containing a regulator.

[0039] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0040] This application provides a method for preparing spherical dihydroxydioxime, the method comprising: simultaneously adding hydrochloric acid solution and dihydroxydioxime metal salt suspension to a reaction substrate containing a regulator to carry out a crystallization reaction to obtain a crystal suspension; filtering the crystal suspension to obtain spherical dihydroxydioxime.

[0041] In the preparation method provided in this application, the "simultaneous addition" of hydrochloric acid and dihydroxyethylenedioxime metal salt suspension means that the concentrations of hydrochloric acid and dihydroxyethylenedioxime metal salt are maintained at a low but uniform level throughout the reaction system. This creates a uniform and continuous supersaturated environment. Under this environment, the nucleation process of spherical dihydroxyethylenedioxime occurs instantaneously, massively, and synchronously, generating a large number of tiny crystal nuclei. At this time, the regulator usually selectively adsorbs on specific crystal faces of the spherical dihydroxyethylenedioxime crystals, inhibiting the growth of those crystal faces, thereby promoting the crystal to develop isotropically (with similar growth rates in all directions), generating particles that are closer to spherical, thus reducing the aspect ratio of the resulting spherical dihydroxyethylenedioxime. Simultaneously, the regulator molecules immediately adsorb onto the surface of these spherical dihydroxyethylenedioxime microcrystal nuclei, forming an organic molecular film. This film effectively reduces van der Waals forces between particles, preventing them from sticking together due to electrostatic and intermolecular forces to form loose, poorly flowing aggregates, thereby improving the flowability of the resulting spherical dihydroxydioxime. Moreover, under the regulation of the modifier, the initially formed tiny primary particles do not exist entirely independently. Guided by the modifier, they self-assemble into denser spherical or near-spherical secondary aggregates. When the resulting spherical dihydroxydioxime particles are similar in size and regular in shape, they are more likely to arrange themselves tightly like a neat stack of spheres, leaving fewer gaps. These "bottom-up" formed secondary particles have a much denser internal structure than the disorderly stacking of needle-like or plate-like crystals, thus significantly increasing the packing density.

[0042] In some specific embodiments, the modifier includes at least one of hydroxypropyl methylcellulose, polyethylene glycol, and sodium dodecyl sulfate.

[0043] In this application, when at least one of hydroxypropyl methylcellulose (HPMC), polyethylene glycol (PEG), and sodium dodecyl sulfate (SDS) is used as a modifier, HPMC, as a partially hydrophilic-lipophilic amphiphilic polymer, can adsorb at the liquid-liquid interface when added to the aqueous phase, effectively reducing interfacial tension and facilitating the formation of smaller, more uniform droplets during emulsification or dispersion, laying the foundation for subsequent spherical particle formation. Furthermore, HPMC can significantly increase the viscosity of the aqueous or organic phase: it can slow down droplet collisions and aggregation, preventing the formation of irregular aggregates; it can inhibit droplet deformation (such as shear deformation) before solidification, allowing sufficient time for the droplets to recover their spherical shape through surface tension; and it can stabilize the emulsion and dispersion system, preventing phase separation. In addition, the long-chain molecules of HPMC or PEG can simultaneously adsorb onto the droplet surface, forming a large, hydrophilic protective layer. This steric barrier effectively prevents particles in the droplets from approaching each other, preventing disordered aggregation, and greatly reducing interparticle friction and electrostatic forces, allowing the powder to flow freely after drying, thus achieving higher flowability. When SDS is used as a modifier, the resulting alkyl sulfate anions are densely adsorbed on the crystal surface, forming a strongly negatively charged interface. These particles with the same charge generate a strong electrostatic repulsion force, far greater than van der Waals attraction, effectively preventing particle aggregation and agglomeration. This ensures that primary particles can exist independently, laying the foundation for subsequent formation of regular morphologies. When the SDS concentration exceeds the critical micelle concentration, spherical micelles form. These micelles can act as "soft templates," guiding reactants to react and crystallize on their surface or within, directly inducing the formation of spherical or near-spherical particles, fundamentally reducing the aspect ratio.

[0044] In some specific embodiments, the dihydroxydioxime metal salt includes the sodium dihydroxydioxime salt.

[0045] In some specific embodiments, the number-average molecular weight of hydroxypropyl methylcellulose is 10,000 g / mol to 1,500,000 g / mol.

[0046] By controlling the molecular weight of the hydroxypropyl methylcellulose used to be between 10,000 g / mol and 1,500,000 g / mol, a more stable emulsion / dispersion system is formed, which effectively inhibits droplet collision and aggregation, providing a quieter environment for the formation and maintenance of spherical droplets. It also protects the droplets from shear deformation, ensuring sphericity. Furthermore, the long-chain molecules of hydroxypropyl methylcellulose within this molecular weight range can form a thicker, more elastic, and mechanically stronger adsorption layer at the liquid-liquid interface, better resisting deformation or breakage caused by internal stresses (such as solvent evaporation and crystal growth stress) during curing, thus maintaining sphericity.

[0047] For example, the number-average molecular weight of the hydroxypropyl methylcellulose used can be 10,000 g / mol, 30,000 g / mol, 50,000 g / mol, 100,000 g / mol, 150,000 g / mol, 200,000 g / mol, 250,000 g / mol, 300,000 g / mol, 3,500,000 g / mol, 400,000 g / mol, 405,000 g / mol, 500,000 g / mol, or 550,000 g / mol. The range is 600,000 g / mol, 650,000 g / mol, 700,000 g / mol, 750,000 g / mol, 800,000 g / mol, 850,000 g / mol, 900,000 g / mol, 1,000,000 g / mol, 1,100,000 g / mol, 1,200,000 g / mol, 1,300,000 g / mol, 1,400,000 g / mol, 1,500,000 g / mol, or any combination thereof.

[0048] In some specific implementations, the regulator accounts for 0.07%-0.09% of the theoretical yield of spherical dihydroxydioxime by mass.

[0049] In this embodiment, by controlling the mass percentage of the regulator in the theoretical yield of spherical dihydroxydioxime to be 0.07%-0.09%, sufficient regulator molecules are ensured to be provided for all spherical dihydroxydioxime particles in the theoretical yield to form a complete monomolecular capping layer. The growth of all crystal faces is moderately and uniformly suppressed, which forces the crystals to grow in an isotropic direction (similar growth rates in all directions), thereby effectively reducing the aspect ratio and forming ideal spherical or short rod-shaped particles.

[0050] For example, the mass percentage of the regulator in the theoretical yield of spherical dihydroxydioxime can be 0.07%, 0.08%, 0.09%, or any combination thereof.

[0051] In some specific implementations, the hydrochloric acid solution has a mass fraction of 12.3%-15.2%.

[0052] In this embodiment, the mass fraction of the hydrochloric acid solution used is controlled to be 12.3%-15.2% to ensure that the reaction system has appropriate H+. + Concentration. Appropriate H₂ +The concentration creates a uniform and continuous supersaturated environment, inducing abundant and synchronous nucleation while ensuring a moderate crystal growth rate. Under this environment, crystals do not have sufficient time to overgrow in a dominant direction; instead, through the synergistic effect of the regulator, they develop isotropically, ultimately forming particles with uniform size, regular morphology (quasi-spherical), and low aspect ratio. Furthermore, this mass fraction of hydrochloric acid solution allows the nucleation rate to be coordinated with the adsorption and spreading rate of the regulator, enabling the regulator to effectively perform its functions of "crystal face passivation" and "steric hindrance," successfully "shaping" the particles into a more ideal spherical shape.

[0053] For example, the mass fraction of the hydrochloric acid solution can be a range of 12.3%, 12.5%, 12.8%, 13.0%, 13.5%, 14.0%, 15.0%, 15.2%, or any combination thereof.

[0054] In some specific embodiments, the mass fraction of dihydroxydioxime metal salt in the dihydroxydioxime metal salt suspension is 12.9%-14.2%.

[0055] In this embodiment, controlling the mass fraction of dihydroxyethylenedioxime metal salt to be between 12.9% and 14.2% ensures that the generation rate of crystal nuclei matches the adsorption rate of the regulator, allowing the regulator sufficient opportunity to uniformly coat each crystal nucleus, effectively performing its functions of "crystal face passivation" and "steric hindrance", and successfully "shaping" spherical particles.

[0056] For example, the mass fraction of dihydroxydioxime metal salt in the dihydroxydioxime metal salt suspension can be 12.9%, 13.2%, 13.5%, 13.8%, 14.0%, 14.2%, or any combination thereof.

[0057] In some specific embodiments, the hydrochloric acid solution and the dihydroxydioxime metal salt suspension are simultaneously added to the reaction base liquid containing the regulator, including: adding the hydrochloric acid solution and the dihydroxydioxime metal salt suspension to the reaction base liquid simultaneously through a dual-tube feeding device; or, adding the hydrochloric acid solution and the dihydroxydioxime metal salt suspension alternately to the reaction base liquid through a pulse feeding device.

[0058] In this embodiment, a dual-tube feeder can be used to simultaneously add hydrochloric acid solution and dihydroxyethylenedioxime metal salt suspension to the reaction substrate, ensuring the uniform distribution of reactants in the reaction system, precisely controlling the acid-base reaction rate, avoiding the crystal nucleus dispersion problem caused by traditional single-tube feeder, and ensuring concentrated crystal nucleus precipitation; alternatively, a pulse feeder can be used to alternately add hydrochloric acid solution and dihydroxyethylenedioxime metal salt suspension to the reaction substrate, achieving the same feeding effect as dual-tube feeder.

[0059] In some specific implementations, the volume ratio of hydrochloric acid solution to reaction substrate is 1:(2-6).

[0060] Hydrochloric acid acts as a precipitant and proton source, releasing free dihydroxyethylenedioxime molecules through its reaction with the metal salt of hydroxyethylethylenedioxime. Crystallization begins when the concentration of these free molecules exceeds their solubility in the system. In this embodiment, by controlling the volume ratio of hydrochloric acid solution to the reaction substrate to 1:(2-6), an optimal balance can be maintained between the rate of new nucleus formation and the rate of existing particle growth in the entire reaction system. This allows the material to continuously and uniformly deposit onto the surface of existing particles, gradually growing into regular spherical shapes in a snowball effect. Moreover, the supersaturation of the system is maintained within a relatively low and constant metastable region, which is conducive to the formation of dihydroxyethylenedioxime particles with higher sphericity.

[0061] For example, the volume ratio of hydrochloric acid solution to reaction substrate can be 1:2, 1:3, 1:4, 1:5, 1:6 or any combination thereof.

[0062] In some specific embodiments, the volume ratio of the dihydroxydioxime metal salt suspension to the reaction substrate is 1:(1.0-1.5).

[0063] In this embodiment, by controlling the volume ratio of the dihydroxydioxime metal salt suspension to the reaction substrate to be 1:(1.0-1.5), a sufficiently high molar or mass concentration of the regulator relative to the dihydroxydioxime metal salt is indirectly ensured. This ensures that each crystal nucleus is "encapsulated" and "guided" by sufficient regulator molecules, inhibiting anisotropic growth and promoting isotropic (spherical) growth. Furthermore, it maintains a low viscosity and good fluidity of the reaction substrate, allowing for sufficient and gentle collisions between crystal particles and between particles and the stirring paddle / vessel wall.

[0064] For example, the volume ratio of the dihydroxydioxime metal salt suspension to the reaction substrate can be 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5 or any combination thereof.

[0065] In some specific implementations, the crystallization reaction temperature is 45℃-55℃, and the crystallization reaction time is 0.5h-3h.

[0066] In this embodiment, excessively high crystallization temperatures can easily lead to "explosive" nucleation, but the subsequent crystal growth rate is also extremely rapid, making the process difficult to control. This can easily result in the formation of numerous small, irregular, and easily agglomerated particles, or the rapid growth can lead to the inclusion of impurities and defects. The aspect ratio may become uncontrollable, resulting in poor flowability. Conversely, excessively low crystallization temperatures result in insufficient nucleation driving force, leading to a small number of crystal nuclei. The existing few crystal nuclei have ample time for anisotropic growth (i.e., preferential growth in a specific direction), easily forming large, needle-like or plate-like crystals with high aspect ratios. This contradicts our desired spherical particles. By controlling the crystallization reaction temperature between 45°C and 55°C, the nucleation rate and growth rate are optimized, producing a moderate number of uniformly sized crystal nuclei that can grow stably and isotropically. Then, by controlling the crystallization reaction time to 0.5h-3h, sufficient time is given for the crystals to grow to the target size, resulting in a dense internal structure and stable surface morphology. This results in particles with a solid structure and smooth surface, which is crucial for improving bulk density and flowability.

[0067] For example, the temperature of the crystallization reaction can be a range of 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, 51°C, 52°C, 53°C, 54°C, 55°C or any combination thereof; the time of the crystallization reaction can be 3 hours.

[0068] In some specific embodiments, after cooling the crystal suspension to room temperature, the crystals are separated by vacuum filtration, washed three times with deionized water, and finally dried at 60°C to obtain spherical dihydroxydioxime.

[0069] The preparation method provided in this application involves simultaneously adding hydrochloric acid and a suspension of dihydroxyethylenedioxime metal salt to a reaction substrate containing a regulator. The polymerization effect of the regulator causes spherical dihydroxyethylenedioxime crystal nuclei to precipitate in a concentrated manner, resulting in a large number of crystals agglomerating into spheres and continuing to grow at the spherical crystal sites. This effectively avoids the problem of excessively dispersed crystal nuclei that are difficult to aggregate into spheres, achieving the preparation of spherical dihydroxyethylenedioxime with excellent flowability, thus improving the flowability and packing density of spherical dihydroxyethylenedioxime.

[0070] Depend on Figure 1 As can be seen, the spherical dihydroxyethylenedioxime prepared in this application has the same crystal form characteristics as the standard DHG crystal, and no new crystal form is generated. This indicates that the preparation method provided in this application does not destroy the intrinsic crystal structure of DHG, and the crystallinity of the obtained spherical dihydroxyethylenedioxime is greater than 95%.

[0071] Figure 2 The morphological image of the spherical dihydroxyethyl oxime provided in this application is as follows: Figure 2As shown, the spherical dihydroxydioxime presents as spherical or near-spherical particles with a smooth surface and no obvious needle-like or plate-like structure. Figure 3 Scanning electron microscope image of spherical dihydroxyethyl oxime provided in this application, as shown below. Figure 3 As shown, spherical dihydroxyethylenedioxime crystals grow radially symmetrically from the central nucleus, forming dense spherical aggregates. The grains are bridged by regulator molecular chains to form a stable polycrystalline structure.

[0072] In some specific embodiments, the aspect ratio of the spherical dihydroxydioxime is less than or equal to 1.5; specifically, it can be 1.2, 1.4, 1.5, etc.

[0073] In some specific embodiments, the SPAN of spherical dihydroxydioxime is 1.0-1.2.

[0074] Figure 6 This is a particle size distribution curve of the dihydroxyethylenedioxime metal salt used in this application. Figure 7 This is a particle size distribution curve of the spherical dihydroxyethylenedioxime prepared in this application. Figure 6 As shown, the D50 particle size of dihydroxyethylenedioxime metal salt is 15.44 μm, and the maximum particle size is less than or equal to 75 μm. For example... Figure 7 As shown, the D50 particle size of spherical dihydroxyethylenedioxime prepared using dihydroxyethylenedioxime metal salt is 172.2 μm, and the maximum particle size is less than or equal to 500 μm. It is evident that molecular self-assembly growth occurs in the preparation method provided in this application. Dihydroxyethylenedioxime metal salt ions diffuse in solution and rearrange and crystallize at specific crystallization sites, thereby forming larger, more regular particles with fewer defects, i.e., spherical dihydroxyethylenedioxime. Furthermore, from... Figure 6 The data shows that the particle size span (SPAN) of dihydroxyethylenedioxime metal salt is 1.740. From... Figure 7 Data shows that in some embodiments, the particle size span (SPAN) of spherical dihydroxyethylenedioxime is 1.117. This indicates that in this application, the irregular small particles of the raw material dihydroxyethylenedioxime metal salt form the regular spherical particles of the product spherical dihydroxyethylenedioxime. The spherical dihydroxyethylenedioxime prepared by the preparation method provided in this application has a narrow particle size distribution and high uniformity.

[0075] In some specific embodiments, the tap density of spherical dihydroxydioxime is greater than or equal to 0.8 g / cm³. 3 Specifically, it can be 0.85 g / cm³. 3 .

[0076] In some specific implementations, spherical dihydroxydioxime does not decompose significantly below 200°C, and its thermal decomposition temperature is greater than 200°C, exhibiting better thermal stability than traditional needle-shaped DHG.

[0077] Figure 4 This is a schematic diagram of the TG-DSC curve of the dihydroxyethylenedioxime metal salt used in this application, for comparison. Figure 4 and Figure 5 The data shows that the thermal decomposition temperature of the obtained spherical dihydroxydioxime is slightly higher than that of the dihydroxydioxime metal salt. This is because the spherical dihydroxydioxime has a strong intermolecular hydrogen bond network that requires higher energy to break. The spherical structure and high crystallinity give it a more regular and stable microstructure, which makes its thermal decomposition temperature higher.

[0078] This application also provides an energetic material, including dihydroxyethylenedioxime prepared by the above preparation method or the above-mentioned dihydroxyethylenedioxime.

[0079] The energetic material provided in this embodiment can perform the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0080] The technical solution of this application will be further described below using specific embodiments.

[0081] Example 1

[0082] A spherical dihydroxydioxime #1 is prepared by the following method:

[0083] Preparation of the reaction base solution: Hydroxypropyl methylcellulose (HPMC) is dissolved in deionized water to form the reaction base solution; wherein, the amount of HPMC used accounts for 0.07% of the theoretical yield of spherical dihydroxydioxime by mass.

[0084] Dual-tube feeding reaction: At 50°C, a 13.8 wt% sodium dihydroxydioxime salt suspension and a 13.8 wt% hydrochloric acid solution were simultaneously added to the reaction substrate through two tubes. The reaction system was maintained at atmospheric pressure and stirred continuously for 3 hours. The volume ratio of the sodium dihydroxydioxime salt suspension to the reaction substrate was 1:1.2, and the volume ratio of the hydrochloric acid solution to the reaction substrate was 1:5.

[0085] Cooling, filtration and drying: After the reaction was completed, the crystals were cooled to room temperature, filtered under vacuum and washed three times with deionized water, and dried at 60°C to obtain spherical dihydroxydioxime #1.

[0086] Example 2

[0087] A spherical dihydroxydioxime #2 is prepared in a manner that is basically the same as in Example 1, except that polyethylene glycol (PEG 400) is used instead of HPMC.

[0088] Example 3

[0089] A spherical dihydroxydioxime #3 is essentially the same as in Example 1, except that sodium dodecyl sulfate (SDS) is used instead of HPMC.

[0090] Example 4

[0091] A spherical dihydroxydioxime #4 is basically the same as that in Example 1, except that the amount of regulator HPMC used is 0.065% of the theoretical yield of the theoretical spherical dihydroxydioxime.

[0092] Example 5

[0093] A spherical dihydroxydioxime #5 is basically the same as that in Example 1, except that the amount of regulator HPMC used is 0.08% of the theoretical yield of the theoretical spherical dihydroxydioxime.

[0094] Example 6

[0095] A spherical dihydroxydioxime #6 is basically the same as that in Example 1, except that the amount of regulator HPMC used is 0.09% by mass of the theoretical yield of the theoretical spherical dihydroxydioxime.

[0096] Example 7

[0097] A spherical dihydroxydioxime #7 is basically the same as that in Example 1, except that the amount of regulator HPMC used is 0.095% of the theoretical yield of the theoretical spherical dihydroxydioxime.

[0098] Example 8

[0099] A spherical dihydroxydioxime #8 is basically the same as that in Example 1, except that the mass fraction of the sodium dihydroxydioxime suspension is 12.9%.

[0100] Example 9

[0101] A spherical dihydroxydioxime #9 is basically the same as that in Example 10, except that the mass fraction of the sodium dihydroxydioxime suspension is 12.5%.

[0102] Example 10

[0103] A spherical dihydroxydioxime #10 is basically the same as that in Example 1, except that the mass fraction of the sodium dihydroxydioxime suspension is 14.2%.

[0104] Example 11

[0105] A spherical dihydroxydioxime #11 is basically the same as that in Example 10, except that the mass fraction of the sodium dihydroxydioxime suspension is 14.5%.

[0106] Example 12

[0107] A spherical dihydroxydioxime #12 is basically the same as that in Example 1, except that the volume ratio of the sodium dihydroxydioxime salt suspension to the reaction substrate is 1:1.0.

[0108] Example 13

[0109] A spherical dihydroxydioxime #13 is basically the same as that in Example 1, except that the volume ratio of the sodium dihydroxydioxime salt suspension to the reaction substrate is 1:1.5.

[0110] Example 14

[0111] A spherical dihydroxydioxime #14 is basically the same as that in Example 12, except that the volume ratio of the sodium dihydroxydioxime salt suspension to the reaction substrate is 1:0.9.

[0112] Example 15

[0113] A spherical dihydroxydioxime #15 is basically the same as that in Example 13, except that the volume ratio of the sodium dihydroxydioxime salt suspension to the reaction substrate is 1:1.6.

[0114] Example 16

[0115] A spherical dihydroxydioxime #16 is essentially the same as in Example 1, except that the hydrochloric acid solution has a mass fraction of 12.3%.

[0116] Example 17

[0117] A spherical dihydroxydioxime #17 is essentially the same as in Example 16, except that the hydrochloric acid solution has a mass fraction of 12%.

[0118] Example 18

[0119] A spherical dihydroxydioxime #18 is essentially the same as in Example 1, except that the hydrochloric acid solution has a mass fraction of 15.2%.

[0120] Example 19

[0121] A spherical dihydroxydioxime #19 is essentially the same as in Example 1, except that the hydrochloric acid solution has a mass fraction of 15.5%.

[0122] Example 20

[0123] A spherical dihydroxydioxime #20 is basically the same as that in Example 1, except that the volume ratio of hydrochloric acid solution to reaction substrate is 1:2.

[0124] Example 21

[0125] A spherical dihydroxydioxime #21 is basically the same as that in Example 1, except that the volume ratio of hydrochloric acid solution to reaction substrate is 1:6.

[0126] Example 22

[0127] A spherical dihydroxydioxime #22 is basically the same as that in Example 20, except that the volume ratio of hydrochloric acid solution to reaction substrate is 1:1.5.

[0128] Example 23

[0129] A spherical dihydroxydioxime #23 is basically the same as that in Example 21, except that the volume ratio of hydrochloric acid solution to reaction substrate is 1:6.5.

[0130] Comparative Example 1

[0131] A dihydroxydioxime #1 is essentially the same as in Example 1, except that HPMC is not used.

[0132] Comparative Example 2

[0133] A dihydroxydioxime #2 is essentially the same as in Example 1, except that hydrochloric acid solution is not used.

[0134] Comparative Example 3

[0135] A dihydroxydioxime #3 is basically the same as that in Example 1, except that hydrochloric acid solution is added first, and then a sodium dihydroxydioxime suspension is added.

[0136] Comparative Example 4

[0137] A dihydroxydioxime #4 is basically the same as that in Example 1, except that a sodium dihydroxydioxime salt suspension is added first, followed by the addition of hydrochloric acid solution.

[0138] The following performance tests were performed on the spherical dihydroxydioxime obtained in the above examples and the dihydroxydioxime obtained in the comparative examples:

[0139] Aspect ratio: The sample was dispersed and sputter-coated with gold. The images were analyzed using a Thermo Fisher field emission scanning electron microscope (QuattroESEM). The major and minor axes of the particles were measured, and their average values ​​and ratios were calculated.

[0140] Flowability: The repose method is used for measurement. Powder is allowed to fall freely through a funnel with a fixed aperture, forming a cone on a plane. The height (h) and the radius of the base (r) of the cone are measured. The angle of repose (θ) = arctan(h / r); the smaller the angle of repose, the better the flowability.

[0141] Tapped density: The tapped density is determined using a tapped density meter. The powder to be tested is placed in a graduated cylinder, ensuring the surface is horizontal. The amplitude, frequency, and number of vibrations are set according to the standard. The final volume of the powder is obtained, and the tapped density is calculated based on the pre-weighed powder mass.

[0142] Thermal decomposition temperature: The TG-DSC curve of the sample is obtained by differential scanning calorimetry. At the inflection point where the TG curve begins to decline significantly, the tangent line intersects the extended baseline. The temperature corresponding to this intersection is the thermal decomposition temperature of the sample.

[0143] The test results are detailed in Table 1:

[0144] Table 1

[0145]

[0146] Note: No product was generated in Comparative Example 2.

[0147] As shown in Table 1, the spherical dihydroxyethylenedioxime prepared by the method provided in this application has an aspect ratio of no more than 3.0, an angle of repose of less than 50°, and a tap density of more than 0.6 g / cm³. 3 The thermal decomposition temperature is not lower than 160℃.

[0148] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for preparing spherical dihydroxyethylenedioxime, characterized in that, include: Hydrochloric acid solution and dihydroxyethylenedioxime metal salt suspension were simultaneously added to the reaction substrate containing a regulator to carry out a crystallization reaction, resulting in a crystal suspension. The crystal suspension was filtered to obtain the spherical dihydroxyethylenedioxime; The regulator includes at least one of hydroxypropyl methylcellulose, polyethylene glycol, and sodium dodecyl sulfate.

2. The preparation method according to claim 1, characterized in that, The dihydroxydioxime metal salt includes dihydroxydioxime sodium salt.

3. The preparation method according to claim 2, characterized in that, The number-average molecular weight of the hydroxypropyl methylcellulose is 10,000 g / mol to 1,500,000 g / mol.

4. The preparation method according to claim 1, characterized in that, The regulator accounts for 0.07%-0.09% of the theoretical yield of the spherical dihydroxyethylenedioxime by mass. And / or, the hydrochloric acid solution has a mass fraction of 12.3%-15.2%; And / or, the mass fraction of the dihydroxyethylenedioxime metal salt in the dihydroxyethylenedioxime metal salt suspension is 12.9%-14.2%.

5. The preparation method according to claim 1, characterized in that, The step of simultaneously adding hydrochloric acid solution and dihydroxyethylenedioxime metal salt suspension to the reaction substrate containing a regulator includes: The hydrochloric acid solution and the dihydroxyethylenedioxime metal salt suspension were simultaneously added to the reaction substrate using a dual-pipe feeding device; Alternatively, the hydrochloric acid solution and the dihydroxyethylenedioxime metal salt suspension can be alternately added to the reaction substrate using a pulse feeding device.

6. The preparation method according to claim 1, characterized in that, The volume ratio of the hydrochloric acid solution to the reaction substrate is 1:(2-6). And / or, the volume ratio of the dihydroxydioxime metal salt suspension to the reaction substrate is 1:(1.0-1.5).

7. The preparation method according to claim 1, characterized in that, The crystallization reaction is carried out at a temperature of 45℃-55℃ for 0.5h-3h.

8. A spherical dihydroxyethylenedioxime, characterized in that, Prepared by the preparation method according to any one of claims 1-7.

9. The spherical dihydroxyethylenedioxime according to claim 8, characterized in that, The aspect ratio of the spherical dihydroxydioxime is less than or equal to 1.5; And / or, the SPAN of the spherical dihydroxydioxime is 1.0-1.2; And / or, the tap density of the spherical dihydroxydioxime is greater than or equal to 0.8 g / cm³. 3 ; And / or, the thermal decomposition temperature of the spherical dihydroxydioxime is greater than 170°C.

10. An energetic material, characterized in that, This includes spherical dihydroxydioxime prepared by the preparation method according to any one of claims 1-7 or spherical dihydroxydioxime according to any one of claims 8-9.

Images