A general high-energy ignition powder and its preparation method

Abstract

The application relates to the field of pyrotechnic smokes and fire agents, and discloses a general high-energy ignition agent formula, which comprises a burning agent, an oxidizing agent, a catalyst and a binder, the burning agent is Al powder and Mg powder, the oxidizing agent is KClO4, Ba(NO3)2 and Fe3O4, the burning catalyst is potassium chlorate, and the binder is alcohol-soluble phenolic resin. The Al powder and the Mg powder are used as the burning agent, the KClO4, the Ba(NO3)2 and the Fe3O4 are used as the oxidizing agent, the potassium chlorate is used as the burning catalyst, and the phenolic resin is used as the binder, so that the problems of low energy level, low burning temperature, poor ignition capacity and easy moisture absorption of the existing ignition agent are solved.

Description

Technical Field

[0001] This application relates to the field of pyrotechnic agents, specifically to a formulation and preparation method of a general-purpose high-energy ignition agent. Background Technology

[0002] Ignition propellants are substances that, under a certain initial external energy, can undergo rapid combustion, generating high-temperature gases, glowing residue, and a large amount of heat, thereby igniting the main charge. Ignition propellants are broadly classified into single-element ignition propellants and compound ignition propellants based on their composition. Single-element ignition propellants are mostly organometallic compounds, such as potassium picrate. Single-element ignition propellants have low heat and low temperature, and their combustion mainly produces gases, resulting in poor ignition ability. Compound ignition propellants generally consist of oxidizers, combustible agents, binders, and additives. These ignition propellants produce more glowing solid particles in their combustion products, have higher heat of combustion, and stronger ignition ability; examples include black powder, boron-based ignition propellants, and zirconium-based ignition propellants. To ensure sufficient reliability of the ignition charge, the ignition charge must meet the following basic requirements: (1) low ignition point (generally required to be below 500℃); (2) high heat of combustion; (3) high combustion temperature; (4) long flame duration; (5) high flame heat flux; (6) at the highest combustion temperature, a large amount of solid products generated by combustion, especially a large amount of molten liquid metal (the ignition ability of molten metal is much higher than that of ordinary solid products); (7) low hygroscopicity; (8) low mechanical sensitivity; (9) cheap and readily available raw materials; (10) simple preparation process.

[0003] However, almost no ignition powder currently meets all the above requirements. The most common boron / potassium nitrate ignition powder has advantages such as a low ignition point, high combustion temperature, large heat of combustion, and long combustion time. However, its combustion products do not produce liquid metal, which poses a significant challenge when igniting flame-retardant main charges (such as magnesium / PTFE). Furthermore, boron / potassium nitrate ignition powder has a certain degree of hygroscopicity, which is unfavorable for long-term deployment and application in high-humidity environments. B / BaCrO4 is also a commonly used ignition powder among gas generators. Its advantage is that at the highest combustion temperature, almost all combustion products are solid, which significantly increases the heat flux of the flame; however, its low heat of combustion, low combustion temperature, and lack of liquid metal formation in combustion products limit its use. Black powder is also a commonly used ignition powder, characterized by high heat, large flame area, low ignition point, and low cost. However, black powder has a low combustion temperature, little high-temperature residue, no liquid metal formation, high sensitivity, and strong hygroscopicity, all of which restrict its use. In addition, zirconium (Zr)-containing ignition propellants are under extensive research because they possess extremely high combustion temperatures. Currently, only zirconium-based ignition propellants have combustion temperatures approaching 4000℃. Therefore, zirconium-based ignition propellants are a good choice for special main charges that are very difficult to ignite. However, zirconium-containing ignition propellants are highly sensitive; even slight external influences can trigger their combustion, posing a challenge to their safety performance. Furthermore, zirconium is an expensive metal and is subject to regulation, making it difficult to purchase. This has prevented the widespread use of zirconium-based ignition propellants. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the existing technology, the purpose of this application is to provide a general-purpose high-energy ignition propellant formulation and its preparation method.

[0005] To achieve the above objectives, this application provides a formulation for a general-purpose high-energy ignition propellant, employing the following technical solution:

[0006] A general-purpose high-energy ignition propellant formulation includes a propellant, an oxidant, a catalyst, and a binder. The propellant is Al powder and Mg powder, the oxidant is KClO4, Ba(NO3)2, and Fe3O4, the combustion catalyst is catoxine, and the binder is an alcohol-soluble phenolic resin.

[0007] Preferably, the composition of each component in the formulation, by mass percentage, is as follows: combustion agent: 30.2%, oxidizer: 64.8%, catalyst: 1.0%, binder: 4.0%.

[0008] Preferably, in the combustion agent, by mass percentage, Al powder accounts for 35.8% and Mg powder accounts for 64.2%.

[0009] Preferably, in the oxidant, by mass percentage, KClO4 accounts for 28.5%, Ba(NO3)2 accounts for 53.5%, and Fe3O4 accounts for 18.0%.

[0010] Preferably, the particle size of Al powder is 10-20 μm, and the particle size of Mg powder is 40-60 μm.

[0011] Preferably, the particle size of Fe3O4 is 5–10 μm.

[0012] Preferably, the Mg powder is a hydrophobic metallic Mg powder, which is prepared by: completely dissolving octadecylamine in dichloromethane, then adding Mg powder, mixing evenly, and drying to obtain coated hydrophobic metallic Mg powder.

[0013] Preferably, the KClO4 and Ba(NO3)2 are a mixture of ultrafine KClO4 and ultrafine Ba(NO3)2, and the preparation method is as follows: KClO4 particles and Ba(NO3)2 particles are put into a ball mill, toluene and stainless steel beads are added, after ball milling, the material is taken out, washed, filtered and dried to obtain a mixture of ultrafine KClO4 and ultrafine Ba(NO3)2 with an average particle size of 3-5 μm.

[0014] Preferably, the KClO4 and Ba(NO3)2 are a mixture of hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2, which is prepared by: completely dissolving octadecylamine in dichloromethane, then adding ultrafine KClO4 and ultrafine Ba(NO3)2, mixing evenly, and then drying to obtain a coated mixture of hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2.

[0015] Another aspect of this application provides a method for preparing a general-purpose high-energy ignition propellant, comprising the following steps: completely dissolving phenolic resin in anhydrous ethanol, then adding captosine and oleic acid dropwise; after captosine and oleic acid are completely dissolved, sequentially adding a mixture of metallic Al powder, hydrophobic metallic Mg powder, hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2 and Fe3O4 powder to the mixed solution, mixing evenly, drying, and then passing the dried material through a 12-mesh sieve to obtain the product.

[0016] Compared with the prior art, this application has the following beneficial effects:

[0017] (1) This application uses Al powder and Mg powder together as a combustion agent, KClO4, Ba(NO3)2 and Fe3O4 together as an oxidant, and catoxine as a combustion catalyst; phenolic resin is used as a binder, which solves the problems of low energy level, low combustion temperature, poor ignition ability and easy moisture absorption of existing ignition propellants.

[0018] (2) The ignition propellant prepared using the formulation and method of this application has the characteristics of easy ignition and high combustion temperature, low friction sensitivity and low hygroscopicity; after combustion, it can produce a large amount of hot slag, including a certain amount of molten metal Fe water, which results in its very strong ignition performance.

[0019] (3) The ignition propellant prepared in this application has the characteristics of simple preparation process and low cost. Attached Figure Description

[0020] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0021] Figure 1 This is a SEM image of the ultrafine KClO4 and ultrafine Ba(NO3)2 mixture prepared in Example 1. Detailed Implementation

[0022] The present application will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0023] Example 1

[0024] A general-purpose high-energy ignition powder formulation, by mass percentage, comprises: 30.2% propellant, 64.8% oxidant, 1.0% catalyst, and 4.0% binder. The propellant is Al powder and Mg powder, the oxidant is KClO4, Ba(NO3)2 and Fe3O4, the combustion catalyst is catoxine, and the binder is alcohol-soluble phenolic resin.

[0025] By mass percentage, the fuel contains 35.8% Al powder and 64.2% Mg powder.

[0026] In the oxidizing agent, by mass percentage, KClO4 accounts for 28.5%, Ba(NO3)2 accounts for 53.5%, and Fe3O4 accounts for 18.0%.

[0027] The particle size of Al powder is 10–20 μm, and the particle size of Mg powder is 40–60 μm.

[0028] The particle size of Fe3O4 is 5–10 μm.

[0029] The preparation process of a general-purpose high-energy ignition propellant includes:

[0030] Step 1: Preparation of hydrophobic metallic Mg powder. Dissolve 0.4 g of octadecylamine completely in 30 mL of dichloromethane, then add 20 g of metallic Mg powder. While sonicating, stir with a glass rod to form a thin mud-like mixture. After mixing for 15 minutes, the material is basically homogeneous. Then, place the thin mud-like mixture into a large petri dish and put it in a water bath oven. After drying at 45°C for 24 hours, the coated hydrophobic metallic Mg powder is obtained.

[0031] Step 2: Preparation of a mixture of ultrafine KClO4 and ultrafine Ba(NO3)2. 34.8 g of coarse KClO4 particles and 65.2 g of coarse Ba(NO3)2 particles were placed in a ball mill, along with 100 mL of toluene and 150 g of stainless steel beads with a diameter of 5 mm. The ball mill was then sealed. The mill speed was adjusted to 150 rpm, and the mill was turned on. After milling for 1.5 hours, the mill was turned off, the material was collected, washed, filtered, and dried to obtain a mixture of ultrafine KClO4 and ultrafine Ba(NO3)2. Figure 1 As can be seen, the particle size of the mixture of ultrafine KClO4 and ultrafine Ba(NO3)2 is about 3 to 5 μm, which falls within the particle size range of ultrafine particles.

[0032] Step 3: Preparation of a hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2 mixture. 1.6 g of octadecylamine was completely dissolved in 50 mL of dichloromethane. Then, 80 g of the ultrafine KClO4 and ultrafine Ba(NO3)2 mixture was added. The mixture was stirred with a glass rod while being sonicated until it formed a thin, muddy consistency. After mixing for 15 minutes, the material became basically homogeneous. This muddy mixture was then placed in a large petri dish and placed in a water bath oven at 45°C for 24 hours to obtain a coated hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2 mixture.

[0033] Step 4: Preparation of high-energy ignition propellant. Dissolve 4 g of alcohol-soluble phenolic resin completely in 80 mL of anhydrous ethanol. Then, add 1 g of captosine and one drop of oleic acid to the solution. After the captosine and oleic acid are completely dissolved, add 10.8 g of metallic Al powder, 19.4 g of hydrophobic metallic Mg powder, 53.2 g of a mixture of hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2, and 11.6 g of Fe3O4 powder to the mixture sequentially. Stir with a glass rod while sonicating until a thin, muddy mixture is formed. After mixing for 30 minutes, the material is basically homogeneous. Then, place the muddy mixture in a large petri dish and put it in a water bath oven at 50°C for 24 hours to dry. Finally, pass the dried material through a 12-mesh sieve to obtain the final product of this application: a general-purpose high-energy ignition propellant.

[0034] Comparative Example 1

[0035] The formulation and preparation method are exactly the same as those in Example 1, except that the KClO4 and Ba(NO3)2 used in this example are not treated. The particle size of KClO4 is 80-120 μm and the particle size of Ba(NO3)2 is 80-120 μm.

[0036] Comparative Example 2

[0037] 5 g of alcohol-soluble phenolic resin was completely dissolved in 80 mL of anhydrous ethanol. Then, 10.8 g of metallic Al powder, 19.4 g of metallic Mg powder, a mixture of 53.2 g of ordinary KClO4 and ordinary Ba(NO3)2, and 11.6 g of Fe3O4 powder were added to the mixture sequentially. The mixture was stirred with a glass rod while being sonicated until it formed a thin, muddy consistency. After mixing for 30 minutes, the material was basically homogeneous. The muddy mixture was then placed in a large petri dish and dried in a water bath oven at 50°C for 24 hours until completely dry. The dried material was then passed through a 12-mesh sieve to obtain the ignition propellant prepared in the comparative example.

[0038] The performance parameters of the ignition propellants prepared in Example 1, Comparative Example 1, and Comparative Example 2 are shown in Table 1. Table 1 also lists the performance parameters of four common ignition propellants. As can be seen from Table 1, Zr / KClO4 has the highest combustion temperature, reaching 3922℃; while the combustion temperature of the ignition propellant prepared in Example 1 is 2720℃, comparable to that of the B / KNO3 ignition propellant. The frictional explosion percentage of the ignition propellant prepared in Example 1 is only 28%, slightly higher than that of B / BaCrO4. Therefore, the ignition propellant prepared in Example 1 is a very insensitive agent to friction. The moisture absorption rate of the ignition propellant prepared in Example 1 is only higher than that of the completely non-hygroscopic B / BaCrO4, and far lower than that of the other ignition propellants. For the ignition propellant prepared in Example 1, its total solid product fraction at the highest temperature is 36.0%, which is not very high, so it does not have an absolute advantage in this respect. However, the ignition powder prepared in Example 1 can produce 7.7% liquid Fe water at the highest temperature, which has a very positive effect on its ignition performance. Furthermore, among all ignition powders, the black powder and the ignition powder prepared in Example 1 have the shortest laser ignition time, indicating that these two agents have excellent ignition performance. Table 1 also shows that, compared to Example 1, the lack of ultrafine treatment of Ba(NO3)2 and KClO4 leads to a decrease in combustion temperature, an increase in friction sensitivity, an increase in moisture absorption rate, and especially a delay in laser ignition time to 1.1 seconds. Therefore, ultrafine treatment of Ba(NO3)2 and KClO4 has a significant impact on their coating effect, and ultrafine treatment of Ba(NO3)2 and KClO4 makes the ignition powder easier to ignite.

[0039] Compared with the ignition propellant prepared in Example 1, the ignition propellant prepared in Comparative Example 2 has a lower combustion temperature, higher friction sensitivity, and higher moisture absorption rate, but the solid fraction and liquid metal fraction remain unchanged, and the laser ignition time is slightly delayed. In Comparative Example 2, the lower combustion temperature is due to the absence of catoroxane. The increased friction sensitivity and moisture absorption rate are due to the lack of hydrophobic coating, and the prolonged laser ignition time is due to the lack of ultrafine processing. In this application, the purpose of ultrafine processing of KClO4 and Ba(NO3)2 is to facilitate coating treatment, as coarse KClO4 and Ba(NO3)2 are not easily coated completely. In addition, according to the inventors' research, the combustion performance of KClO4 and Ba(NO3)2 is also significantly improved after ultrafine processing. Moreover, the use of octadecaneamine to coat ultrafine KClO4 and ultrafine Ba(NO3)2 in this application can significantly reduce the moisture absorption of KClO4 and Ba(NO3)2, and the sensitivity is also greatly reduced. Uncoated Mg powder will absorb moisture from the air and deteriorate; while coated Mg powder does not have such hygroscopicity and has a very good hydrophobic effect. Moreover, the coating process also reduces the sensitivity of Mg powder.

[0040] Table 1. Performance comparison of Example 1, Comparative Example 1, Comparative Example 2, and common ignition propellants.

[0041]

[0042] Table 2 shows the ignition of magnesium / PTFE charges by different igniters under normal pressure. As can be seen from Table 2, 40 mg of the igniter prepared in Example 1 is sufficient to stably ignite the magnesium / PTFE charge. In contrast, black powder requires 250 mg; B / KNO3 requires 100 mg; B / BaCrO4 requires 50 mg; and Zr / KClO4 requires only 30 mg to stably ignite the main charge. Therefore, the combustion temperature of 3922℃ and 50.7% solid product determine that it is the igniter with the strongest ignition capability. The igniter prepared in Example 1 has an ignition capability second only to Zr / KClO4, due to its higher combustion temperature, moderate solid product, and 7.7% liquid metal content. Therefore, the igniter prepared in Example 1 is an extremely powerful igniter, with an ignition capability essentially on par with the strongest zirconium-based igniters currently available. Furthermore, the ignition capability of the ignition propellant in Comparative Example 1 is also relatively strong, but lower than that of the ignition propellant in Example 1. The results from Example 1 and Comparative Example 1 show that the ignition capability of the ignition propellant is stronger after Ba(NO3)2 and KClO4 are ultra-finely refined.

[0043] Table 2. Ignition of magnesium / PTFE charge by different igniters under normal pressure (√ indicates the charge was ignited; × indicates the charge was not ignited; each charge was measured three times for each type of igniter).

[0044]

[0045] The specific embodiments of this application have been described above. It should be understood that this application is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the substantive content of this application.

Claims

1. A general-purpose high-energy ignition propellant, characterized in that, The mixture includes a combustion agent, an oxidant, a catalyst, and a binder. The combustion agent is Al powder and Mg powder, wherein the Mg powder is hydrophobic metallic Mg powder. The oxidant is KClO4, Ba(NO3)2, and Fe3O4. The KClO4 and Ba(NO3)2 are a mixture of hydrophobic ultrafine KClO4 and hydrophobic ultrafine Ba(NO3)2 with an average particle size of 3-5 μm. The combustion catalyst is catoxine, and the binder is an alcohol-soluble phenolic resin.

2. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, By mass percentage, the contents of each component in the formula are as follows: combustion agent: 30.2%, oxidizer: 64.8%; Catalyst: 1.0%; Adhesive: 4.0%.

3. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, In the fuel, by mass percentage, Al powder accounts for 35.8% and Mg powder accounts for 64.2%.

4. The formulation of the general-purpose high-energy ignition propellant according to claim 1, characterized in that, In the oxidant, by mass percentage, KClO4 accounts for 28.5%, Ba(NO3)2 accounts for 53.5%, and Fe3O4 accounts for 18.0%.

5. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, The particle size of Al powder is 10–20 μm, and the particle size of Mg powder is 40–60 μm.

6. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, The particle size of Fe3O4 is 5–10 μm.

7. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, The preparation method of the hydrophobic metal Mg powder is as follows: octadecaneamine is completely dissolved in dichloromethane, then Mg powder is added, mixed evenly, and dried to obtain coated hydrophobic metal Mg powder.

8. The general-purpose high-energy ignition propellant according to claim 1, characterized in that, The preparation method of the mixture of hydrophobic ultrafine KClO4 and hydrophobic ultrafine Ba(NO3)2 is as follows: KClO4 particles and Ba(NO3)2 particles are put into a ball mill, toluene and stainless steel beads are added, after ball milling, the material is taken out, washed, filtered and dried to obtain a mixture of ultrafine KClO4 and ultrafine Ba(NO3)2 with an average particle size of 3-5 μm. Octadecylamine was completely dissolved in dichloromethane, and then ultrafine KClO4 and ultrafine Ba(NO3)2 were added, mixed evenly, and then dried to obtain a mixture of coated hydrophobic ultrafine KClO4 and hydrophobic ultrafine Ba(NO3)2.

9. A method for preparing a general-purpose high-energy ignition propellant according to any one of claims 1-8, characterized in that, Includes the following steps: Completely dissolve phenolic resin in anhydrous ethanol, then add captosine and oleic acid dropwise. After captosine and oleic acid are completely dissolved, add a mixture of metal Al powder, hydrophobic metal Mg powder, hydrophobic ultrafine KClO4 and ultrafine Ba(NO3)2 and Fe3O4 powder to the mixed solution in sequence. Mix well, dry, and then pass the dried material through a 12-mesh sieve to obtain the final product.

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