Eutectic inhibitor and method for inhibiting formation of eutectic

Abstract

The invention belongs to the field of energetic materials, and discloses an effective method for inhibiting the formation of AB eutectic for a long time, which can ensure that a mixture of A and B does not form eutectic within 25 years when coexisting under conventional storage conditions by adding a eutectic inhibitor. When a small amount of inhibitor is added, the high-temperature acceleration experiment product of the A and B mixture is still a physical mixture of A and B, the X-ray powder diffraction characteristic peak of the product is the physical superposition of the A crystal and the B crystal, and no new characteristic diffraction peak belonging to the A and B eutectic crystal appears, so that the problem that the performance of the propellant is reduced due to the eutectic crystal formed when the A and B mixtures coexist is effectively solved.

Description

Technical Field

[0001] The present invention belongs to the field of energetic materials, and in particular relates to a method for inhibiting eutectic formation and a eutectic inhibitor. Background Art

[0002] A, chemical formula is C6H6N 12 O 12 , relative molecular mass 338.185, chemical name is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, its structure is shown below:

[0003]

[0004] A is a white powder, easily soluble in solvents such as acetone, ethyl acetate, acetonitrile, dimethyl sulfoxide, etc., and has low solubility in water, alkanes and alcohols.

[0005] B, molecular formula C4H8N8O8, molecular weight 296.17, chemical name 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, its structure is shown below:

[0006]

[0007] B is a white powder with good solubility in dimethyl sulfoxide, N,N-dimethylformamide, and acetone, but low solubility in most other organic solvents.

[0008] Currently known crystal forms of A include α, β, ε, γ, and ζ, of which ε-A is the most stable and has the highest practical value. Crystal forms of B include α, β, δ, and γ, of which β-HMX is the most stable, boasting the highest density, lowest mechanical sensitivity, and highest stability, making it the most valuable for practical applications. However, in practice, using A alone presents challenges such as high burning rate and high sensitivity, so B is added to reduce these. However, during storage, a mixture of A and B can form a eutectic, leading to pores in the propellant, affecting its mechanical properties, energy efficiency, and lifespan, reducing its safety, and making it difficult to meet the requirements for safe propellant storage.

[0009] However, there is currently no method to inhibit the formation of AB eutectics, resulting in a short stable storage life for corresponding solid propellants, which severely restricts the development of new A-based solid propellants. Therefore, to meet the demand for long-term stable storage of solid propellants in defense and military applications, it is necessary to develop technologies that effectively and permanently inhibit the formation of AB eutectics. This can inhibit the formation of AB eutectics, ensure the stability of the propellant, and extend its storage life, thereby avoiding the economic waste caused by premature destruction and the dangerous consequences of delayed replacement. Summary of the Invention

[0010] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an effective method for permanently inhibiting the formation of AB eutectic.

[0011] Among them, A, chemical formula is C6H6N 12 O 12 , relative molecular mass 338.185, chemical name is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, its structure is shown below:

[0012]

[0013] B, molecular formula C4H8N8O8, molecular weight 296.17, chemical name 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, its structure is shown below:

[0014]

[0015] The eutectic inhibitor provided by the present invention ensures that the A and B mixtures do not form eutectics within 25 years of coexistence under conventional storage conditions, effectively solving the problem of eutectic formation when the A and B mixtures coexist, which in turn leads to a decrease in the performance of the energetic material system. The present invention adopts a method of adding a eutectic inhibitor to solve the problem of eutectic within the storage and use temperature range of the A and B mixtures. When a small amount of inhibitor is added, the high-temperature accelerated test product of the A and B mixture is a physical mixture of A and B. The X-ray powder diffraction characteristic peaks of the physical mixture of A and B only include the characteristic peaks of A and B, and no new characteristic diffraction peaks attributable to the AB eutectic appear.

[0016] In order to achieve the above object, the present invention provides a cocrystal inhibitor for inhibiting the formation of cocrystal between compound A and compound B, wherein the cocrystal inhibitor is a polymer and / or an organic small molecule;

[0017] The compound A is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, and its chemical formula is C6H6N 12 O 12 , the structural formula is:

[0018]

[0019] The compound B is 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, with a chemical formula of C4H8N8O8 and a structural formula of:

[0020]

[0021] Preferably, any of the above items is that the polymer comprises at least one of chitosan, cellulose, polyvinyl pyrrolidone, and polyethylene.

[0022] Preferably, any of the above items is that the small molecule comprises at least one of acetic acid, nitric acid, pyridine, and 1,4-diiodotetrafluorobenzene.

[0023] In any of the above, preferably, the cocrystal inhibitor accounts for 0.1% to 5% of the total weight, more preferably 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5% and ranges therebetween. The total weight is the total weight of Compound A, Compound B and the cocrystal inhibitor.

[0024] In any of the above, preferably, when the eutectic inhibitor is in solid form, its particle size is 5 μm to 200 μm, more preferably 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200 μm and ranges therebetween.

[0025] Preferably, any of the above items has a molecular weight of the polymer of 1,000-80,000, more preferably 1,000, 5,000, 10,000, 20,000, 30,000, 40,000, 50,000, 60,000, 70,000, 80,000 and ranges therebetween.

[0026] The present invention also provides a propellant prepared according to any one of the above co-crystal inhibitors, wherein the propellant comprises compound A, compound B and any one of the above co-crystal inhibitors.

[0027] The present invention also provides a method for inhibiting the formation of AB cocrystal using the cocrystal inhibitor according to any one of the above items, wherein the cocrystal inhibitor according to any one of the above items is added to a mixture of compound A and compound B, and the method for inhibiting the formation of AB cocrystal comprises the following steps:

[0028] Wherein component A is compound A, and component B is compound B;

[0029] Step 1: Add component A and component B to the propellant formula and mix well;

[0030] Step 2: adding the eutectic inhibitor to the mixture obtained in step 1 and mixing uniformly;

[0031] Step 3: Place the mixture obtained in step 2 in a 70°C oven for high-temperature aging treatment.

[0032] Preferably, in any of the above methods, in step 1, component A and component B are added to the propellant formulation at a certain temperature and in a certain molar ratio.

[0033] Preferably, in any of the above items, in step 1, the certain temperature is 10-50°C, more preferably 10, 20, 30, 40, 50°C and ranges therebetween.

[0034] Preferably, in any of the above items, in step 1, the mixing is carried out at a temperature of 10 to 50° C., more preferably 10, 20, 30, 40, 50° C. and ranges therebetween.

[0035] In any of the above, preferably, the certain molar ratio is a molar ratio of the amount of A and B added of 0:1 to 1:0, where 0 means that no substance is added. Further preferred molar ratios of A and B are 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1, and ranges therebetween, i.e., in the mixture of A and B, the proportion of A is 0-100%, and the proportion of B is 100-0%.

[0036] Preferably, in any of the above items, in step 2, the amount of the eutectic inhibitor added is 0.1% to 5% of the total weight, more preferably 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5% and ranges therebetween.

[0037] Any of the above is preferably that in step 2, when the eutectic inhibitor is in liquid form, its particle size is 5 μm to 200 μm, more preferably 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200 μm and ranges therebetween.

[0038] Preferably, in any of the above items, in step 2, the stirring and mixing time is 0.5 to 1.5 h, more preferably 0.5, 1.0, 1.5 h and the range therebetween.

[0039] The present invention also provides the use of polymers and / or small organic molecules as co-crystal inhibitors of compound A and compound B.

[0040] The present invention also provides the use of polymers and / or small organic molecules in the preparation of any of the above-mentioned co-crystal inhibitors or any of the above-mentioned propellants.

[0041] Preferably, any of the above items is that the polymer includes at least one of chitosan, cellulose, polyvinyl pyrrolidone, and polyethylene; and the small molecule includes at least one of acetic acid, nitric acid, pyridine, and 1,4-diiodotetrafluorobenzene.

[0042] In a preferred embodiment of the present invention, a method for inhibiting the formation of AB eutectic is provided, comprising the following steps:

[0043] Step 1: Add component A and component B to the propellant at a certain temperature and in a certain molar ratio, and mix them evenly;

[0044] Step 2: adding the eutectic inhibitor to the above mixture at a certain temperature and in a certain proportion, and mixing evenly;

[0045] Step 3: Place the mixture obtained in step 2 in a 70°C oven for high-temperature aging treatment, and take samples every 5 days to detect the formation of eutectic.

[0046] Preferably, in any of the above items, the addition amounts of component A and component B in step 1 are 0:1 to 1:0 (0 means no addition of the substance).

[0047] In any of the above items, the mixing temperature in step 1 is preferably 10 to 50° C., more preferably 20, 30, 40° C. or room temperature.

[0048] Preferably, in any of the above items, the eutectic inhibitor in step 2 is a polymer or a small organic molecule.

[0049] In any of the above, preferably, the inhibitor in step 2 is a polymer such as chitosan, cellulose, polyvinyl pyrrolidone, polyethylene, etc. Further preferably, the molecular weight (MW) of the polymer is 1,000-80,000.

[0050] Preferably, in any of the above items, the inhibitor in step 2 is an organic small molecule such as acetic acid, nitric acid, pyridine, or 1,4-diiodotetrafluorobenzene.

[0051] Preferably, in any of the above items, the amount of the inhibitor added in step 2 is 0.1% to 5% of the total weight.

[0052] Preferably, in any of the above items, when the inhibitor in step 2 is in solid form, its particle size is 5 μm to 200 μm.

[0053] Preferably, in any of the above items, in step 2, the stirring and mixing time is 0.5 to 1.5 hours.

[0054] The present invention provides new applications of polymers and organic small molecules as cocrystal inhibitors of compound A and compound B. In a preferred embodiment of the present invention, the effects of polymers such as chitosan, cellulose, polyvinyl pyrrolidone, and polyethylene and organic small molecules such as acetic acid, nitric acid, pyridine, and 1,4-diiodotetrafluorobenzene are verified. In a preferred embodiment of the present invention, taking ε-A crystal and β-B crystal as an example, the eutectic inhibitor is added to the mixture of ε-A crystal and β-B crystal, and its X-ray powder diffraction characteristic peaks are physical superpositions of ε-A crystal (X-ray powder diffraction characteristic peaks are located at 2θ=10.72°, 12.60°, 12.82°, 13.82°, 15.74°, 16.32° and 17.74°) and crystal β-B (X-ray powder diffraction characteristic peaks are located at 2θ=14.70°, 16.04°, 18.26°, 20.56°), and no new characteristic diffraction peaks belonging to the AB eutectic appear (its characteristic diffraction peaks are located at 2θ=10.96°, 11.56°, 13.30°, 14.92° and 15.12°). It should be noted that the above only takes ε-A crystal and β-B crystal as examples. The cocrystal inhibitor and the method for inhibiting cocrystal formation provided by the present invention are applicable to compound A and compound B of any crystal form.

[0055] The advantages and beneficial effects of the present invention are:

[0056] (1) The method for inhibiting AB eutectic formation provided by the present invention has a simple process and good stability, and is suitable for the long-term stable storage of propellants containing both components A and B;

[0057] (2) The AB eutectic inhibitor provided by the present invention has a small addition amount (the minimum addition amount is 0.1%) and has minimal impact on the overall performance of the propellant and the performance of the A and B components in the propellant;

[0058] (3) The AB cocrystal inhibitor provided by the present invention is low in price, highly safe, has good compatibility, and is highly drugable. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 1 is the X-ray powder diffraction pattern of the sample at different storage times at 70°C in preferred embodiment 1 of the present invention.

[0060] Figure 2 These are microscope images of samples stored at 70° C. for different storage times in preferred embodiment 1 of the present invention.

[0061] Figure 3 This is the X-ray powder diffraction pattern of the sample stored at 70°C for two days in Comparative Example 1.

[0062] Figure 4 This is a microscope image of the sample stored at 70°C for two days in Comparative Example 1. DETAILED DESCRIPTION

[0063] The present invention is described more clearly and completely by the following examples, but the examples described are only some embodiments of the present invention, not all. The examples are for helping to understand the present invention and should not be used to limit the scope of the present invention. The reagents involved in the present invention are all products in the prior art and can be purchased through commercial channels or prepared according to the methods described in the prior art.

[0064] The chitosan is a commercial product or prepared according to existing methods. In a preferred embodiment of the present invention, the chitosan preferably has a molecular weight of 1000, a particle size of 200 μm, a degree of deacetylation of 85%, and a viscosity of 1%. Preferably, the chitosan is prepared according to the chitosan preparation method described in Chinese Patent No. CN201410426235.7, with publication number CN104211833A and publication date December 17, 2014.

[0065] The cellulose is a commercial product or prepared according to existing methods. In a preferred embodiment of the present invention, the cellulose preferably has a MW of 80,000 and a particle size of 90-130 μm D50, more preferably a particle size of 150 μm. Preferably, the cellulose is prepared according to the cellulose preparation method described in Chinese Patent CN201510355532.1, with publication number CN104878638B and publication date September 15, 2017.

[0066] The polyvinyl pyrrolidone is a commercial product or prepared according to a conventional method. Preferably, the polyvinyl pyrrolidone is prepared according to the preparation method of polyvinyl pyrrolidone described in Chinese patent CN201711166303.0, patent publication number CN107880157A, and publication date April 6, 2018.

[0067] The polyethylene is a commercial product or is prepared according to the existing technology. In a preferred embodiment of the present invention, the linear low-density polyethylene produced by Beijing Yinuokai Technology Co., Ltd. is preferably used.

[0068] Acetic acid is a commercial product or prepared according to the prior art method. In a preferred embodiment of the present invention, acetic acid from Shanghai Bid Pharmaceutical Technology Co., Ltd. is preferably used, and the preferred concentration is 96%.

[0069] Nitric acid is a commercial product or prepared according to the existing technology. In a preferred embodiment of the present invention, nitric acid AR of Tianjin Jiangtian Chemical Technology Co., Ltd. is preferably used.

[0070] Pyridine is a commercial product or prepared according to the prior art method. In a preferred embodiment of the present invention, the pyridine of Kmart (Tianjin) Chemical Technology Co., Ltd. AR is preferred.

[0071] 1,4-diiodotetrafluorobenzene is a commercial product or prepared according to the existing technology. In a preferred embodiment of the present invention, 98% 1,4-diiodotetrafluorobenzene produced by Shanghai Bid Pharmaceutical Technology Co., Ltd. is preferably used.

[0072] Among them, for polymer eutectic inhibitors, the molecular weight of chitosan, cellulose, polyvinyl pyrrolidone, and polyethylene is preferably 1000-80000;

[0073] Among them, chitosan, cellulose, polyvinyl pyrrolidone, polyethylene, and 1,4-diiodotetrafluorobenzene are in solid form, and the particle size is preferably 5 μm to 200 μm.

[0074] Wherein, acetic acid, nitric acid, and pyridine are in liquid form. The concentration of the nitric acid is preferably 65% ​​to 98%, preferably 68%, 60%, 55%, 50%, 40%, and 30%, and ranges therebetween, preferably 35% to 45%, preferably 10% to 20%, and preferably 98% or greater. The concentration of the acetic acid is preferably 2%, 3%, 30%, 80%, 56%, 99%, and ranges therebetween, and preferably 99% or greater. The present invention is not limited to the concentration of the liquid eutectic inhibitor; any concentration of acetic acid, nitric acid, or pyridine is suitable for use in the present invention.

[0075] In the following examples, all ingredients other than Compound A, Compound B, and the cocrystal inhibitor are collectively referred to as the "real solvent." The "real solvent" encompasses other components of the propellant, including binders, plasticizers, oxidants, and curing agents. It should be noted that the components contained in the "real solvent" are all known in the prior art. The technical solutions and effects of the present invention are not limited by the composition and proportions of the "real solvent." In other words, the composition of the "real solvent" does not affect the technical effect of the cocrystal inhibitor in inhibiting the formation of cocrystals between Compound A and Compound B.

[0076] Example 1

[0077] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0078] At room temperature, 21.6 mg of chitosan (MW = 1000, particle size of 200 μm, added in an amount of 0.1% of the total weight), 7.2 g of ε-A and 2.4 g of β-B were added to 12 g of real solvent and stirred for 1.5 h to mix them evenly; then the evenly mixed sample was placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0079] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0080] Example 2

[0081] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0082] At 10°C, 1.08g of pyridine (5.0% of the total weight), 7.2g of ε-A and 2.4g of β-B were added to 12g of real solvent and stirred for 0.5h to mix them evenly; then the evenly mixed sample was placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0083] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0084] Example 3

[0085] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0086] At 50°C, 540 mg of polyethylene (MW = 80000, particle size 5 μm, added in an amount of 2.5% of the total weight), 7.2 g of ε-A and 2.4 g of β-B were added to 12 g of real solvent and stirred for 1 hour to mix them evenly; then the evenly mixed sample was placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0087] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, indicating the absence of characteristic peaks at AB and ε-A. Microscopic examination revealed the absence of flaky products.

[0088] Example 4

[0089] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0090] At 40°C, 800 mg of polyvinylpyrrolidone (MW = 58000, particle size 60 μm, added in an amount of 3.7% of the total weight), 7.2 g of ε-A and 2.4 g of β-B were added to 12 g of real solvent and stirred for 1.5 hours to mix them evenly; the evenly mixed sample was then placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0091] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0092] Example 5

[0093] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0094] At 30°C, 21.6 mg of cellulose (MW = 80,000, particle size 150 μm, added in an amount of 0.1% of the total weight), 7.2 g of ε-A and 2.4 g of β-B were added to 12 g of real solvent and stirred for 45 minutes to mix them evenly. The mixed sample was then placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0095] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0096] Example 6

[0097] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0098] At 50°C, 400 mg of acetic acid (1.9% of the total weight), 7.2 g of ε-A, and 2.4 g of β-B were added to 12 g of real solvent and stirred for 1 hour to mix them evenly. The mixed sample was then placed in a 70°C oven for high-temperature storage testing. Samples were taken for testing every 5 days.

[0099] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0100] Example 7

[0101] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0102] At 10°C, 200 mg of nitric acid (0.9% of the total weight), 7.2 g of ε-A, and 2.4 g of β-B were added to 12 g of real solvent and stirred for 1.5 h to mix them evenly. The mixed sample was then placed in a 70°C oven for high-temperature storage testing. Samples were taken for testing every 5 days.

[0103] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0104] Example 8

[0105] A method for inhibiting the formation of AB eutectic, comprising the following steps:

[0106] At room temperature, 100 mg of 1,4-diiodotetrafluorobenzene (particle size 200 μm, added in an amount of 0.5% of the total weight), 7.2 g of ε-A and 2.4 g of β-B were added to 12 g of real solvent and stirred for 30 minutes to mix them evenly; the evenly mixed sample was then placed in a 70°C oven for high-temperature storage testing; samples were taken for testing every 5 days.

[0107] The X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2°, and 20.56°±0.2°, which were attributed to ε-A and β-B. The characteristic peaks of the AB eutectic were absent. Microscopic results showed that no flaky products were formed.

[0108] Comparative Example 1

[0109] Comparative Example 1 is similar to Example 1, except that no inhibitor is added in Comparative Example 1.

[0110] The sample fully formed a cocrystal within two days. The X-ray powder diffraction pattern of the sample exhibited characteristic peaks at diffraction angles 2θ = 10.96°, 11.56°, 13.30°, 14.92°, and 15.12°, which are attributed to the AB cocrystal. Microscopic results showed that the AB cocrystal product was completely formed in the form of flakes.

[0111] Comparative Example 2

[0112] Comparative Example 2 is similar to Example 1, except that no inhibitor is added in Comparative Example 2 and the storage temperature is lowered to 50°C.

[0113] The sample began to form a cocrystal on day 13 and completely formed a cocrystal on day 15. The X-ray powder diffraction pattern of the sample after storage for 5 days showed characteristic peaks at diffraction angles 2θ = 10.72°±0.2°, 12.60°±0.2°, 12.82°±0.2°, 13.82°±0.2°, 14.70°±0.2°, 15.74°±0.2°, 16.04°±0.2°, 16.32°±0.2°, 17.74°±0.2°, 18.26°±0.2° and 20.56°±0.2°, which were attributed to ε-A and β-B, but no characteristic peaks of AB cocrystal appeared. After 13 days of storage, characteristic peaks of the AB eutectic appeared at 2θ = 10.96°, 11.56°, 13.30°, 14.92°, and 15.12°. After 15 days of storage, the X-ray powder diffraction pattern of the product showed characteristic peaks at diffraction angles of 2θ = 10.96°, 11.56°, 13.30°, 14.92°, and 15.12°, respectively. Microscopic observations revealed the gradual formation of flaky products.

[0114] Property detection:

[0115] 1) The inhibitors in Examples 1-8 and Comparative Examples 1-2 were tested for their eutectic formation effects. No eutectics formed in the samples from Examples 1-8 during storage at 70°C ± 1°C for 150 days, demonstrating that the inhibitors and inhibition methods proposed in the present invention can effectively inhibit the formation of AB eutectics. The results are shown in Table 1.

[0116] Table 1 Investigation of the inhibitory effect of inhibitors on AB eutectic formation

[0117] 5 days 15 days 30 days 50 days 80 days 110 days 130 days 150 days Example 1 mixture mixture mixture mixture mixture mixture mixture mixture Example 2 mixture mixture mixture mixture mixture mixture mixture mixture Example 3 mixture mixture mixture mixture mixture mixture mixture mixture Example 4 mixture mixture mixture mixture mixture mixture mixture mixture Example 5 mixture mixture mixture mixture mixture mixture mixture mixture Example 6 mixture mixture mixture mixture mixture mixture mixture mixture Example 7 mixture mixture mixture mixture mixture mixture mixture mixture Example 8 mixture mixture mixture mixture mixture mixture mixture mixture Comparative Example 1 eutectic eutectic eutectic eutectic eutectic eutectic eutectic eutectic Comparative Example 2 mixture eutectic eutectic eutectic eutectic eutectic eutectic eutectic

[0118] 2) If Figure 1 The X-ray powder diffraction patterns of the samples stored in real solvents for different time periods obtained in Example 1 are shown. The results show that there is no AB eutectic. The X-ray powder diffraction patterns of the samples stored in different inhibitors for different time periods obtained in Examples 1-8 are shown. Figure 1 Therefore, it is not repeated here.

[0119] 3) If Figure 2 The following are microscopic images of samples stored in real solvents for different periods of time obtained in Example 1 (a is 5 days, b is 15 days, c is 30 days, d is 50 days, e is 80 days, f is 110 days, g is 130 days, and h is 150 days). The results show that there is no lamellar AB eutectic. Microscopic images of samples stored for different periods of time under the action of different inhibitors obtained in Examples 1-8 Figure 1 Therefore, it is not repeated here.

[0120] 4) Figure 3This is the X-ray powder diffraction pattern of the sample stored at 70°C for two days in Comparative Example 1.

[0121] 5) Figure 4 This is a microscope image of the sample stored at 70°C for two days in Comparative Example 1.

[0122] Conventional research in this field typically uses 70°C as an accelerated testing temperature. In the embodiments of the present invention, experiments were conducted at 70°C. Over a period of more than 110 days, a mixture of Compound A and Compound B, exposed to the cocrystal inhibitor of the present invention, did not form a cocrystal of Compound A and Compound B. Based on the results of this accelerated process, the Arrhenius equation, and the results in Table 1, it can be deduced that the cocrystal inhibitor of the present invention prevents the formation of a cocrystal when the mixture of Compound A and Compound B is coexisting under conventional storage conditions for 25 years. Conventional storage conditions are preferably ambient temperature and pressure.

[0123] The present invention discloses and proposes a method for effectively inhibiting the formation of AB eutectic. Those skilled in the art can implement the method by referring to the content of this article and appropriately changing the raw materials, process parameters, and other aspects. The method and product of the present invention have been described through preferred embodiments. It is obvious that those skilled in the art can modify or appropriately change and combine the method and product described herein without departing from the content, spirit, and scope of the present invention to implement the technology of the present invention. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in the spirit, scope, and content of the present invention.

[0124] The above embodiments are provided for illustrative purposes only and are not intended to limit the scope of implementation. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to provide an exhaustive list of all implementations. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A cocrystal inhibitor for inhibiting the formation of cocrystal between compound A and compound B, characterized in that: The co-crystal inhibitor is a polymer and / or an organic small molecule; The compound A is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, and its chemical formula is C6H6N 12 O 12 , the structural formula is: The compound B is 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, with a chemical formula of C4H8N8O8 and a structural formula of:

2. The eutectic inhibitor according to claim 1, wherein The polymer includes at least one of chitosan, cellulose, polyvinyl pyrrolidone, and polyethylene; the small molecule includes at least one of acetic acid, nitric acid, pyridine, and 1,4-diiodotetrafluorobenzene.

3. The eutectic inhibitor according to claim 2, characterized in that The co-crystal inhibitor accounts for 0.1% to 5% of the total weight, and the total weight is the total weight of compound A, compound B and the co-crystal inhibitor.

4. The eutectic inhibitor according to claim 2, wherein The eutectic inhibitor is a polymer, and the molecular weight of the polymer is 1000-80000; when the eutectic inhibitor is in solid state, the particle size of the eutectic inhibitor is 5 μm to 200 μm.

5. The propellant prepared from the eutectic inhibitor according to any one of claims 1 to 4, characterized in that: The invention comprises compound A, compound B and the co-crystal inhibitor according to any one of claims 1 to 4.

6. The method for inhibiting the formation of AB cocrystal using a cocrystal inhibitor according to any one of claims 1 to 4, characterized in that: The method of adding the cocrystal inhibitor according to any one of claims 1 to 4 to a mixture of compound A and compound B, wherein the method of inhibiting the formation of AB cocrystal comprises the following steps: Wherein component A is compound A, and component B is compound B; Step 1: Add component A and component B to the propellant formula and mix well; Step 2: adding the eutectic inhibitor to the mixture obtained in step 1 and mixing uniformly; Step 3: Place the mixture obtained in step 2 in a 70°C oven for high-temperature aging treatment.

7. The method according to claim 6, wherein In step 1, component A and component B are added to the propellant formula in a certain molar ratio at a certain temperature, wherein the certain temperature is 10-50°C, and are mixed uniformly at a temperature of 10-50°C; the certain molar ratio is a molar ratio of the amount of A and B added of 0:1 to 1:0, where 0 means that the substance is not added.

8. The method according to claim 6, wherein The amount of the eutectic inhibitor added in step 2 is 0.1% to 5% of the total weight; when the eutectic inhibitor is in solid form, its particle size is 5 μm to 200 μm; and the stirring and mixing time is 0.5 to 1.5 h.

9. Use of a polymer and / or an organic small molecule in the preparation of the co-crystal inhibitor according to any one of claims 1 to 4 or the propellant according to claim 5.

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