A sodium carboxymethyl cellulose-polyazomethine glycidyl ether co-coated aluminum-lithium alloy powder and a preparation method thereof
By co-coating with sodium carboxymethyl cellulose and polyazolidone glycidyl ether, the problem of easy detachment of high-energy components from the surface of aluminum-lithium alloy powder was solved, thereby improving the combustion heat and propellant performance of aluminum-lithium alloy powder.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING INST OF TECH
- Filing Date
- 2024-05-27
- Publication Date
- 2026-06-09
AI Technical Summary
High-energy components on the surface of aluminum-lithium alloy powder are prone to detachment, resulting in poor compatibility with propellants and making it difficult to stably introduce high-energy components onto the surface of aluminum-lithium alloy powder, thus affecting propellant performance.
A method of co-coating sodium carboxymethyl cellulose with polyazidoglycidyl ether is adopted. First, a dense sodium carboxymethyl cellulose layer is formed on the surface of aluminum-lithium alloy powder, and then polyazidoglycidyl ether is grafted onto its surface to form a stable intermediate carrier to fix the high-energy components.
It improves the heat of combustion of aluminum-lithium alloy powder and the combustion performance of propellant, enhances the stability of high-energy components, prevents detachment, and improves the energy release level of propellant.
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Figure CN118496047B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azidoglycidyl ether) and its preparation method, belonging to the field of energetic materials technology. Background Technology
[0002] To improve propellant performance, the modification of metallic fuels has become a research goal for many scholars. Currently, aluminum-based metallic fuel propellants improve combustion performance by grafting high-energy components (GAPs) onto the surface of aluminum powder. Compared to pure aluminum powder, aluminum-lithium alloys have a higher heat of combustion and more energy. For aluminum-lithium alloys, AP propellants containing aluminum-lithium alloy powder can effectively reduce HCl gas emissions. Using aluminum-lithium alloy powder as a high-energy additive in solid propellants can improve both the specific impulse of the propellant and the performance of the weapon. It is an ideal fuel among solid propellants. However, to meet the increasingly demanding requirements of propellants, the method of grafting high-energy components onto the outer surface of aluminum-lithium alloy powder needs further improvement. Due to the high reactivity of lithium and other metallic elements in aluminum-lithium alloy powder, its compatibility with other components in the propellant is poor. Traditional high-energy components grafted onto the surface of aluminum-lithium alloy powder are easily detached. Enabling high-energy components to function effectively on the alloy powder surface is very difficult. Therefore, a stable intermediate carrier is needed to introduce high-energy components onto the surface of aluminum-lithium alloy powder. Summary of the Invention
[0003] In view of this, the purpose of the present invention is to provide an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether, and a method for preparing the same.
[0004] To achieve the above objectives, the technical solution of the present invention is as follows.
[0005] A sodium carboxymethyl cellulose (CMC)-poly(glycidyl azido) ether co-coated aluminum-lithium alloy powder, wherein sodium carboxymethyl cellulose (CMC) is chelated with aluminum and coated on the surface of the aluminum-lithium alloy powder, and poly(glycidyl azido) ether (GAP) is grafted onto the surface of sodium carboxymethyl cellulose (CMC); the degree of substitution of sodium carboxymethyl cellulose is less than 1.
[0006] Preferably, the coating amount of sodium carboxymethyl cellulose (CMC) is 3% to 8% of the mass of the aluminum-lithium alloy powder, and the coating amount of poly(glycidyl azido) ether (GAP) is 1% to 5% of the mass of the aluminum-lithium alloy powder.
[0007] Preferably, the degree of substitution of the sodium carboxymethyl cellulose is 0.3 to 0.9.
[0008] Preferably, the molecular weight of the poly(glycidyl azide) ether (GAP) is 4,000 to 20,000.
[0009] Preferably, the aluminum-lithium alloy powder contains 95% to 98% aluminum by mass and 2% to 5% lithium by mass.
[0010] Preferably, the particle size of the aluminum-lithium alloy powder is 5μm to 50μm.
[0011] A method for preparing aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azidoglycidyl ether) according to the present invention, comprising the following steps:
[0012] (1) Disperse sodium carboxymethyl cellulose in water to obtain sodium carboxymethyl cellulose colloid, drain the water to obtain the drained colloid;
[0013] (2) Add the drained colloid to the first organic solvent, stir and mix evenly, then add aluminum-lithium alloy powder, stir and react for 10 min to 30 min, so that sodium carboxymethyl cellulose forms a dense coating layer on the surface of aluminum-lithium alloy powder. After the reaction is completed, centrifuge, wash and dry to obtain aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0014] (3) The aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether are added to the second organic solvent and stirred for 30 min to 90 min. After the reaction is completed, the mixture is centrifuged, washed and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether.
[0015] Preferably, the sodium carboxymethyl cellulose accounts for 9% to 13% of the mass of the aluminum-lithium alloy powder; and the polyazidoglycidyl ether accounts for 4% to 7% of the mass of the aluminum-lithium alloy powder.
[0016] Preferably, in step (2), the first organic solvent is one or more of ethyl acetate, isopropanol, acetone and anhydrous ethanol.
[0017] Preferably, in step (3), the second organic solvent is an isopropanol solution of ethyl acetate and n-hexane.
[0018] An application of the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether according to the present invention, wherein the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether is used as a high-energy additive for solid propellants.
[0019] Beneficial effects
[0020] This invention provides an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose (CMC) and poly(azide glycidyl ether). Compared with ordinary modified aluminum-lithium alloy powder, CMC can form a chelate with aluminum. Aluminum helps CMC form a superstructure, allowing it to tightly coat the surface of the aluminum-lithium alloy powder. Furthermore, the interaction between aluminum ions and the carboxyl groups in CMC causes the molecular chains to curl, thus significantly reducing viscosity. Small lithium particles can approach the negative charges on the carboxyl groups in CMC more closely, greatly weakening the polyelectrolyte effect and further reducing viscosity, preventing agglomeration of the alloy powder due to excessive CMC viscosity. After CMC is introduced onto the alloy powder surface, the added GAP can further react with the CMC surface through hydroxyl groups, tightly coating the CMC surface. The coated aluminum-lithium alloy powder is not directly connected to the GAP, avoiding the large-scale detachment of GAP caused by the high activity and low compatibility of lithium. As an energetic binder for propellants, GAP itself can significantly improve the energy level of the alloy powder. The alloy powder containing azide can release a large amount of heat value during decomposition without an oxygen environment. This has significant implications for improving the energy of aluminum-lithium alloy powder itself and its subsequent application in propellants.
[0021] This invention provides a method for preparing aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose (CMC) and poly(azide glycidyl ether). Addressing the problem of high-energy coating layer detachment due to the high reactivity of the lithium phase region in aluminum-lithium alloys, this invention first gels a specific CMC, then modifies the aluminum-lithium alloy powder to obtain a CMC coating layer. GAP is introduced to react with the CMC layer on the alloy powder surface. Utilizing the CMC intermediate shell, GAP is successfully introduced into the aluminum-lithium alloy without contacting the aluminum-lithium alloy powder surface. This solves the problem of difficulty in introducing high-energy components into aluminum-lithium alloy powder due to the high reactivity of lithium.
[0022] This invention provides an application of aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose (CMC) and glycidyl azidophosphate (GAP). The combustion heat of the CMC-GAP-coated aluminum-lithium alloy powder is significantly increased compared to the original powder. Furthermore, the successful introduction of GAP significantly improves the propellant compatibility of the CMC-GAP-coated alloy powder in propellants. Additionally, the increased combustion heat also enhances the combustion performance of the propellant. Attached Figure Description
[0023] Figure 1 The image shows a comparison of scanning electron microscope (SEM) images of sodium carboxymethyl cellulose-polyazide glycidyl ether coated aluminum-lithium alloy powder (left) in Example 1 and GAP-coated aluminum-lithium alloy powder (right) in Comparative Example 1 after one week of storage.
[0024] Figure 2The images show the morphology of the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether in Example 1 (left) and the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether in Comparative Example 2 (right) after drying.
[0025] Figure 3 The image shows the EDS diagram of the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether in Example 1.
[0026] Figure 4 The image shows the viscosity results after mixing AlCl3 and CMC in Example 1.
[0027] Figure 5 The image shows the infrared spectrum of the aluminum-lithium alloy co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether as described in Example 1. Detailed Implementation
[0028] The present invention will be further described in detail below with reference to specific embodiments.
[0029] Comparative Example 1
[0030] At room temperature and pressure, 10g of aluminum-lithium alloy powder (10% lithium content, 50μm particle size) was added to 200mL of ethyl acetate. After stirring for 20min, 0.5g of glycidyl azidophosphate (GAP) was added and stirred for another 20min to allow the GAP to form a dense coating on the aluminum-lithium alloy surface. After the reaction was completed, the powder was centrifuged, washed, centrifuged again, and dried to obtain a polyazolidyl azidophosphate-coated aluminum-lithium alloy powder.
[0031] Comparative Example 2
[0032] 1 g of CMC with a substitution number of 1.3 was dissolved in 2 ml of water to prepare a hydrogel, and excess water was drained. At room temperature and pressure, the CMC hydrogel was added to 200 mL of ethyl acetate and stirred for 20 min. Then, 10 g of aluminum-lithium alloy powder (lithium content 4.3%, particle size 50 μm) was added and stirred for 20 min to allow the CMC to fully react with the surface of the aluminum-lithium alloy powder. After the reaction was complete, the mixture was centrifuged and washed to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0033] The coated aluminum-lithium alloy powder was transferred to a reactor vessel, 200 ml of ethyl acetate was added, and 0.6 g of GAP was weighed and added to the reactor vessel. The mixture was stirred for 30 min. After the reaction was completed, the powder was centrifuged, washed, centrifuged again, and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether).
[0034] Example 1
[0035] 1 g of CMC with a substitution number of 0.7 was dissolved in 2 ml of water to prepare a hydrogel, and excess water was drained. At room temperature and pressure, the CMC hydrogel was added to 200 mL of ethyl acetate and stirred for 20 min. Then, 10 g of aluminum-lithium alloy powder (lithium content 4.3%, particle size 50 μm) was added and stirred for 20 min to allow the CMC to fully react with the surface of the aluminum-lithium alloy powder. After the reaction was complete, the mixture was centrifuged and washed to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0036] The coated aluminum-lithium alloy powder was transferred to a reactor vessel, 200 ml of ethyl acetate was added, and 0.6 g of GAP was weighed and added to the reactor vessel. The mixture was stirred for 30 min. After the reaction was completed, the powder was centrifuged, washed, centrifuged again, and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether).
[0037] Electron micrograph of the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether described in this embodiment after one week of storage. Figure 1 (Right) Electron micrographs of GAP-coated aluminum-lithium alloy powder from Comparative Example 1 after one week of storage. Figure 1 Compare (left) with, for example Figure 1 As shown in the comparison, it was found that the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose-polyazide glycidyl ether described in this embodiment maintained a certain degree of sphericity in the coating layer after one week of storage, and the surface was relatively dense. After one week of storage, the aluminum-lithium alloy powder with GAP coating in Comparative Example 1 showed coating layer fracture, indicating significant high-energy coating layer fracture. This demonstrates that the aluminum-lithium alloy powder prepared in this embodiment has better storage performance than ordinary GAP-coated modified aluminum-lithium alloy powder.
[0038] Combustion heat tests were conducted on the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether) as described in this embodiment, and the initial aluminum-lithium alloy powder. All tests were repeated three times, and the average value was taken. As shown in Table 1, when 0.5 g of both the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether) as described in this embodiment and the unmodified aluminum-lithium alloy powder were tested under the same conditions, the results showed that the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether) as described in Example 1 had a higher energy release level, indicating that the modification of the alloy powder had a certain effect.
[0039] Table 1
[0040]
[0041] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether described in this embodiment ( Figure 2 (Left) and Comparative Example 2: aluminum-lithium alloy powder ( Figure 2(Right) Product morphology analysis was performed. CMC is an anionic polymer; the increase in molecular chain length leads to increased intermolecular electrostatic repulsion, causing molecules to tend to extend and increasing their hydrodynamic volume. Since solution viscosity is a measure of the hydrodynamic volume of macromolecules, it is assumed that the viscosity of CMC colloids increases with increasing degree of substitution. Figure 2 As can be seen, when CMC with a degree of substitution greater than 1 is treated, the aluminum-lithium alloy powder exhibits obvious agglomeration due to the high viscosity of CMC with a high degree of substitution, which affects the further application of the alloy powder.
[0042] To further investigate the coating of sodium carboxymethyl cellulose and poly(azide glycidyl ether), EDS testing was performed on Example 1, and the results are as follows: Figure 3 As shown, a large amount of nitrogen element has been introduced into the surface of the alloy powder, which can be considered as GAP being successfully introduced into the surface of the alloy powder.
[0043] To verify the chelating effect of sodium carboxymethyl cellulose (CMC) and aluminum, a soluble aluminum salt (AlCl3) and CMC were mixed and their viscosity was analyzed. The results are as follows: Figure 4 As shown, in dilute CMC solutions, sodium cations are far from the polymer chains, while anionic polymer chains repel each other, resulting in a more extended polymer chain configuration and larger size. The solution viscosity is high. When aluminum salts are added, the increase in aluminum cations is equivalent to increasing the concentration of counterions, weakening the chain diffusion caused by electrostatic repulsion between anions, strengthening the coiling effect, further reducing the size, and lowering the solution viscosity. According to... Figure 4 As we can see, with Al 3+ As the concentration increases, the solution viscosity decreases. However, when Al... 3+ When the concentration increases to a certain level, the solution viscosity does not decrease but rather increases. This is because Al 3+ Unlike monovalent cations, Al 3+ With its large atomic size, it can chelate with the long anionic chains of CMC to form a superstructure, which further increases the viscosity of the system. Figure 4 The viscosity change curve also confirms this.
[0044] To verify whether GAP successfully binds to CMC, the aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether) described in this embodiment was subjected to infrared analysis. The results are as follows: Figure 5 As shown in the figure, the infrared absorption peaks of carboxyl and azide groups are clearly visible, indicating that CMC and GAP have been successfully attached to the surface of the aluminum-lithium alloy powder. Furthermore, the peaks are located at 1067 cm⁻¹. -1 The absorption peak at that point is the absorption peak of the COC bond, indicating that CMC binds to GAP through -OH.
[0045] Example 2
[0046] 1 g of CMC with a substitution number of 0.5 was dissolved in 2 ml of water to prepare a hydrogel, and excess water was drained. At room temperature and pressure, the CMC hydrogel was added to 200 mL of ethyl acetate and stirred for 20 min. Then, 10 g of aluminum-lithium alloy powder (lithium content 5%, particle size 50 μm) was added and stirred for another 20 min to allow the CMC to fully react with the surface of the aluminum-lithium alloy powder. After the reaction was complete, the mixture was centrifuged and washed to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0047] The coated aluminum-lithium alloy powder was transferred to a reactor vessel, 150 ml of acetone was added, and 0.5 g of GAP was weighed and added to the reactor vessel. The mixture was stirred for 30 min. After the reaction was completed, the powder was centrifuged, washed, centrifuged again, and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether).
[0048] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether described in this embodiment remained dense and stable after being stored for one week.
[0049] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment showed no obvious clumping after drying.
[0050] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment has a high energy release level.
[0051] Example 3
[0052] 1 g of CMC with a substitution number of 0.9 was dissolved in 2 ml of water to prepare a hydrogel, and excess water was drained. At room temperature and pressure, the CMC hydrogel was added to 200 mL of ethyl acetate and stirred for 20 min. Then, 10 g of aluminum-lithium alloy powder (lithium content 4.7%, particle size 30 μm) was added and stirred for 20 min to allow the CMC to fully react with the surface of the aluminum-lithium alloy powder. After the reaction was complete, the mixture was centrifuged and washed to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0053] The coated aluminum-lithium alloy powder was transferred to a reactor vessel, 150 ml of acetone was added, and 0.5 g of GAP was weighed and added to the reactor vessel. The mixture was stirred for 30 min. After the reaction was completed, the powder was centrifuged, washed, centrifuged again, and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether).
[0054] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether described in this embodiment remained dense and stable after being stored for one week.
[0055] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment showed no obvious clumping after drying.
[0056] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment has a high energy release level.
[0057] Example 4
[0058] 1 g of CMC with a substitution number of 0.8 was dissolved in 2 ml of water to prepare a hydrogel, and excess water was drained. At room temperature and pressure, the CMC hydrogel was added to 200 mL of ethyl acetate and stirred for 20 min. Then, 10 g of aluminum-lithium alloy powder (lithium content 4.7%, particle size 30 μm) was added and stirred for 20 min to allow the CMC to fully react with the surface of the aluminum-lithium alloy powder. After the reaction was complete, the mixture was centrifuged and washed to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose.
[0059] The coated aluminum-lithium alloy powder was transferred to a reactor vessel, and 150 ml of n-hexane and 50 ml of isopropanol were added. 0.5 g of GAP was weighed and added to the reactor vessel, and the mixture was stirred for 30 minutes. After the reaction was complete, the powder was centrifuged, washed, centrifuged again, and dried to obtain an aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose-polyazidoglycidyl ether.
[0060] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether described in this embodiment remained dense and stable after being stored for one week.
[0061] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment showed no obvious clumping after drying.
[0062] The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether described in this embodiment has a high energy release level.
[0063] In summary, the invention includes, but is not limited to, the above embodiments. Any equivalent substitutions or partial improvements made under the spirit and principles of this invention shall be considered to be within the protection scope of this invention.
Claims
1. An aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and poly(azide glycidyl ether), characterized in that: Sodium carboxymethyl cellulose is chelated with aluminum and coated on the surface of aluminum-lithium alloy powder, and polyazolidone is grafted onto the surface of sodium carboxymethyl cellulose; the degree of substitution of sodium carboxymethyl cellulose is less than 1. The coating amount of sodium carboxymethyl cellulose is 3% to 8% of the mass of the aluminum-lithium alloy powder, and the coating amount of polyazidoglycidyl ether is 1% to 5% of the mass of the aluminum-lithium alloy powder.
2. The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in claim 1, characterized in that: The degree of substitution of the sodium carboxymethyl cellulose is 0.3 to 0.
9.
3. The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone glycidyl ether as described in claim 1, characterized in that: The molecular weight of the polyazidoglycidol is 4000~20000.
4. The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in claim 1, characterized in that: The aluminum-lithium alloy powder contains 95% to 98% aluminum by mass and 2% to 5% lithium by mass.
5. The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in claim 1, characterized in that: The particle size of the aluminum-lithium alloy powder is 5μm~50μm.
6. A method for preparing aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in any one of claims 1 to 5, characterized in that: The method steps include: (1) Disperse sodium carboxymethyl cellulose in water to obtain sodium carboxymethyl cellulose colloid, drain the water to obtain the drained colloid; (2) Add the drained colloid to the first organic solvent, stir and mix evenly, then add aluminum-lithium alloy powder, stir and react for 10 min to 30 min, so that sodium carboxymethyl cellulose forms a dense coating layer on the surface of aluminum-lithium alloy powder. After the reaction is completed, centrifuge, wash and dry to obtain aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose. (3) The aluminum-lithium alloy powder coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether are added to the second organic solvent and stirred for 30 min to 90 min. After the reaction is completed, the mixture is centrifuged, washed and dried to obtain an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether. The amount of sodium carboxymethyl cellulose used is 9% to 13% of the mass of the aluminum-lithium alloy powder, and the amount of polyazidoglycidyl ether used is 4% to 7% of the mass of the aluminum-lithium alloy powder.
7. The method for preparing aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in claim 6, characterized in that: In step (2), the first organic solvent is one or more of ethyl acetate, isopropanol, acetone and anhydrous ethanol; In step (3), the second organic solvent is an isopropanol solution of ethyl acetate and n-hexane.
8. The application of an aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazolidone as described in any one of claims 1 to 5, characterized in that: The aluminum-lithium alloy powder co-coated with sodium carboxymethyl cellulose and polyazidoglycidyl ether is used as a high-energy additive for solid propellants.