Kerosene gel propellant and method for preparing the same
By functionalizing boron particles with halogenated alkylsilanes, the problems of difficult ignition and incomplete combustion of boron particles in propellants were solved, resulting in a highly efficient and stable kerosene gel propellant that improves combustion efficiency and energy density.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NAT UNIV OF DEFENSE TECH
- Filing Date
- 2024-03-22
- Publication Date
- 2026-06-02
AI Technical Summary
Traditional liquid hydrocarbon fuels are difficult to meet the high energy requirements of aerospace propulsion systems. Boron particles are difficult to ignite in propellants, burn slowly and incompletely, and high solid loads inhibit energy release. Existing surface modification methods are uneven and unstable.
By functionalizing boron particles with halogenated alkylsilanes to form a -BO-Si- architecture, the miscibility and stability of boron with kerosene are increased. The ignition and combustion of boron are promoted by halogen free radicals, and kerosene gel propellant is prepared.
It significantly improves the combustion efficiency and stability of kerosene gel propellants, with boron loading reaching 60% and combustion efficiency exceeding 95%. It also improves energy characteristics and dispersibility, and reduces agglomeration and sedimentation.
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Figure CN118221488B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of propellant technology, specifically relating to a kerosene gel propellant and its preparation method. Background Technology
[0002] Traditional liquid hydrocarbon fuels are insufficient to meet the high-energy requirements of current aerospace propulsion systems. Developing high-energy propulsion technologies has become a research hotspot worldwide. Adding high-energy solid particles such as boron, aluminum, and magnesium can significantly improve the calorific value and density of traditional liquid hydrocarbon fuels. Boron, due to its high calorific value and density, is an ideal solid additive for traditional liquid hydrocarbon fuels, leading to the development of a series of novel propellants, such as boron-containing slurries or gels. However, the high melting and boiling points of the boron oxide layer limit its oxidation process in the solid phase, resulting in problems such as difficult ignition, slow and incomplete combustion, thus affecting the actual performance of the propellant. Furthermore, these novel propellants require sufficiently high solid loading to achieve a considerable energy density, but research has found that high solid loading makes boron particles more difficult to burn, significantly inhibiting energy release. To alleviate this concern, modifying boron particles to promote combustion in boron-containing propellants is a feasible strategy.
[0003] Extensive research has been conducted on promoting the ignition and combustion of boron. One common method is to add additives such as combustible metals (Mg, Ti, or Fe), metal oxides (NiO, CuO, or Bi₂O₃), or fluoropolymers (polytetrafluoroethylene). Another method is to coat the boron surface with graphene or cover it with hydrocarbons, metal fluorides, or fluorocarbons. However, surface modification of boron is usually achieved through physical methods such as mechanical grinding or coating, resulting in uneven and unstable surface layer distribution, which still affects the actual performance of high-load boron-containing kerosene gel propellants. Summary of the Invention
[0004] The problem to be solved by the present invention is to provide a kerosene gel propellant and its preparation method. By functionalizing boron with halogen alkylsilane, the modified boron is added to the kerosene gel propellant, which gives it high stability, excellent ignition performance and high combustion efficiency.
[0005] The present invention includes a kerosene gel propellant comprising the following components in the indicated mass ratios:
[0006] Kerosene: 37 wt.% to 68 wt.%;
[0007] Modified boron: 30 wt.% to 60 wt.%;
[0008] Gelling agent: 2 wt.% to 5 wt.%;
[0009] The modified boron is a halogenated alkylsilane functionalized boron obtained by chemically combining halogenated alkylsilanes with boron, and the halogenated alkylsilane functionalized boron includes a -BO-Si- architecture.
[0010] Furthermore, the boron is amorphous boron powder with a particle size range of 0.5–0.8 μm.
[0011] Furthermore, halogenated alkylsilanes include alkylsilanes containing fluorine, chlorine, bromine, or iodine.
[0012] Furthermore, halogenated alkyl silanes include one of (3-fluoropropyl)trimethoxysilane, (3-chloropropyl)trimethoxysilane, (3-bromopropyl)trimethoxysilane, (3-iodopropyl)trimethoxysilane, (3,3,3-trifluoropropyl)triethoxysilane, 1H,1H,2H,2H-perfluorooctyltriethoxysilane, and 1H,1H,2H,2H-perfluorodecyltriethoxysilane.
[0013] Furthermore, the halogenated alkylsilane is one of 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane or 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane.
[0014] Furthermore, the gelling agent includes one or a combination of polyurethane, polyvinyl alcohol, gelatin, polyamide resin and hydroxyethyl cellulose;
[0015] As a general inventive concept, the present invention also includes a method for preparing a kerosene gel propellant, comprising the following steps:
[0016] A gelling agent and modified boron were added to kerosene, stirred evenly, and allowed to stand at room temperature to obtain a kerosene gel propellant containing halogenated alkylsilane functionalized boron.
[0017] Furthermore, a gelling agent and modified boron are added to the kerosene, the stirring temperature is 50-80℃, the stirring speed is 1000-2500 rpm, the stirring time is 10-30 min, and the standing time is 5-10 min.
[0018] Furthermore, the preparation method of modified boron includes the following steps:
[0019] S1. Add boron powder to dichloromethane and ultrasonically disperse for 0.5–1 hour;
[0020] S2. Add a halogenated alkylsilane reagent to the solution obtained in S1 and disperse it by ultrasonication for 20-30 min;
[0021] S3. Stir the solution obtained in S2 magnetically at room temperature for 12-24 hours to obtain a mixed solution;
[0022] S4. Wash the mixture obtained from S3 with dichloromethane, centrifuge, and vacuum dry to obtain halogenated alkylsilane functionalized boron.
[0023] Furthermore, the halogenated alkylsilane has a mass of 20% to 30% of the boron mass.
[0024] The beneficial effects of this invention are:
[0025] 1. This invention utilizes the natural hydroxyl groups (-OH) on the surface of boron to react with halogenated alkylsilanes to form covalent -BO-Si- bonds, thereby covalently functionalizing the boron surface with halogenated alkyl groups. At the same time, since each halogenated alkylsilane also has three alkoxy groups, polycondensation can occur to form multilayer functional groups. Compared with the physical mixing of boron and fluorine-containing additives, this chemical modification method results in a higher contact area and a shorter diffusion distance between the modifying agent and boron. The combination of the two is more stable and uniform, and the thickness is relatively controllable, enabling the propellant to obtain more stable performance.
[0026] 2. The halogenated alkylsilane used in this invention forms halogenated alkyl functional groups on the surface of modified boron, which imparts strong hydrophobicity to boron, enhancing the miscibility of boron with kerosene and allowing the system to accommodate more boron particles. This achieves a high boron loading, significantly improving the propellant's calorific value and density. The boron-containing kerosene gel propellant provided by this invention can have a boron loading of up to 60%, and the combustion efficiency can reach over 95% based on measured and theoretical calorific values. Furthermore, the hydrophobic and stable coating layer reduces the adsorption and interaction forces between boron particles in kerosene, improves the dispersion of boron particles, reduces boron agglomeration in kerosene and sedimentation during gelation, thus enhancing the stability of the boron-containing kerosene gel.
[0027] 3. The halogenated alkylsilane functionalized boron used in this invention can generate halogen free radicals such as F, Cl, and Br during combustion. These free radicals can improve the overall combustion efficiency of the propellant. On the one hand, halogen free radicals can react with boron to form boron halides, generating more heat of reaction, while consuming the oxide layer, accelerating the ignition and combustion of boron, and reducing the formation of condensed phases, thus making combustion more stable. On the other hand, halogen free radicals have high activity and can undergo disproportionation reactions with unsaturated small molecules produced by kerosene decomposition to generate highly active small molecule products, which further burn to produce water and carbon dioxide, reducing the carbon deposition effect of kerosene. Attached Figure Description
[0028] Appendix Figure 1 This is the XPS depth profile result of FOTS-B in one embodiment of the present invention. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Furthermore, the technical solutions of the various embodiments of this invention can be combined with each other, but only on the basis of being achievable by one of ordinary skill in the art. When a combination of technical solutions is contradictory or impossible to implement, such a combination should be considered non-existent and not within the scope of protection claimed by this invention.
[0031] Unless otherwise specified, all chemical reagents used in the embodiments of this invention are commercially available.
[0032] This invention provides a kerosene gel propellant, comprising the following components in the indicated mass ratios:
[0033] Kerosene: 37 wt.% to 68 wt.%;
[0034] Modified boron: 30 wt.% to 60 wt.%;
[0035] Gelling agent: 2 wt.% to 5 wt.%;
[0036] The modified boron is a halogenated alkylsilane functionalized boron obtained by chemically combining halogenated alkylsilanes with boron, and the halogenated alkylsilane functionalized boron includes a -BO-Si- architecture.
[0037] In this invention, the naturally occurring hydroxyl groups (-OH) on the boron surface react with halogenated alkylsilanes to form covalent -BO-Si- bonds, thus covalently functionalizing the boron surface with halogenated alkyl groups. Simultaneously, since each halogenated alkylsilane also possesses three alkoxy groups, polycondensation can occur, forming multilayer functional groups. Compared to the physical mixing of boron and fluorine-containing additives, this chemical modification method results in a higher contact area and shorter diffusion distance between the modifying agent and boron, leading to a more stable and uniform bond with relatively controllable thickness, thus enabling the propellant to achieve more stable performance.
[0038] In this embodiment of the invention, the hydrophobicity of the halogen alkyl functional groups on the modified boron surface is utilized to achieve high boron content particle loading, thereby significantly improving the energy performance (calorific value and density) of the kerosene gel. In this embodiment of the invention, the boron loading of the boron-containing kerosene gel propellant can reach up to 60%, and the combustion efficiency can reach over 95% by comparing the measured calorific value with the theoretical calorific value. At the same time, the surface hydrophobicity improves the dispersibility of boron particles, reducing their agglomeration in kerosene and sedimentation during gelation. In addition, the halogen alkyl silane used in this embodiment of the invention contains halogen elements, which generate highly active halogen free radicals during combustion, accelerating the ignition and combustion of boron and reducing the carbon deposition effect of kerosene, thereby significantly improving the combustion performance of the boron-containing propellant.
[0039] In a preferred embodiment, the boron used is amorphous boron powder with a particle size ranging from 0.5 to 0.8 μm. The small particle size of nano-sized powder facilitates dispersion and provides a larger specific surface area, meaning more reaction and adsorption sites, thus improving the modification effect. Furthermore, nano-powders are beneficial for subsequent combustion. If the particles are even smaller, they are more prone to agglomeration, which is detrimental to modification or subsequent combustion, and is also expensive, making cost control difficult. Conversely, if the particle size is too large, the specific surface area is small, requiring more modifying reagents and hindering subsequent combustion.
[0040] In a preferred embodiment, the halogenated alkylsilane comprises an alkylsilane containing fluorine, chlorine, bromine, or iodine. The alkoxy group in the halogenated alkylsilane undergoes a dehydration reaction with the hydroxyl group on the boron. Preferably, the halogenated alkylsilane contains multiple halogen atoms; a greater number of halogen atoms promotes better combustion of the boron particles and results in higher combustion efficiency.
[0041] In a preferred embodiment, the halogenated alkylsilane includes one of (3-fluoropropyl)trimethoxysilane (FPTS), (3-chloropropyl)trimethoxysilane (CPTS), (3-bromopropyl)trimethoxysilane (BPTS), (3-iodopropyl)trimethoxysilane (IPTS), (3,3,3-trifluoropropyl)triethoxysilane (TFPTS), 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FOTS), or 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FDTS). In this invention, the modified boron obtained by modification with FPTS is designated as FPTS-B. The designation method for other halogenated alkylsilane-modified boron is the same. The modified boron in the embodiments of this invention includes one of FPTS-B, CPTS-B, BPTS-B, IPTS-B, TFPTS-B, FOTS-B, or FDTS-B. These halogenated alkylsilanes can undergo dehydration reactions with hydroxyl groups to generate stable halogenated alkyl functional groups; they can also enhance the hydrophobicity of boron, improve its miscibility with kerosene, and reduce particle agglomeration and sedimentation; halogen free radicals such as F and Cl participate in the boron reaction, reducing ignition delay and enhancing combustion. Other fluorinated substances are difficult to form stable modified functional layers with boron, partly because other fluorinated substances are mostly produced using physical methods such as coating, resulting in uncontrollable and unstable functional layer thickness, or weak chemical bonds that are easily broken; and partly because they require special preparation conditions or processing, increasing process complexity. More preferably, the halogenated alkylsilane is FOTS or FDTS; FOTS contains 13 F atoms, and FDTS contains 17 F atoms. The more F atoms, the better the combustion effect of boron particles and the higher the combustion efficiency.
[0042] In a preferred embodiment, the gelling agent includes one or a combination of polyurethane, polyvinyl alcohol, gelatin, polyamide resin, and hydroxyethyl cellulose; the gelling agent can form hydrogen bonds with halogen groups (with greater electronegativity) such as F and Cl in the modified boron, thereby further enhancing the stability of boron particles in the kerosene gel system; the combination of the above different gelling agents has a semi-interpenetrating or interpenetrating network, which can improve the overall stability of the gel.
[0043] This invention also provides a method for preparing a kerosene gel propellant, comprising the following steps:
[0044] A gelling agent and modified boron were added to kerosene, stirred evenly, and allowed to stand at room temperature to obtain a kerosene gel propellant containing halogenated alkylsilane functionalized boron.
[0045] The preparation process of this invention is simple, requiring no additional surfactants to stabilize and suspend boron particles. This avoids the problem of excessive kerosene volatilization and negative impact on the overall energy performance of the propellant caused by the long preparation time in traditional methods. Furthermore, the kerosene gel propellant provided by this invention can be prepared in a one-pot process, reducing kerosene volatilization during the sol-gel process and thus minimizing propellant energy loss.
[0046] Furthermore, in the above steps, the stirring temperature is 50–80℃, the stirring speed is 1000–2500 rpm, the stirring time is 10–30 min, and the settling time is 5–10 min.
[0047] In a preferred embodiment, modified boron is prepared by a dehydration and condensation reaction between a halogenated alkylsilane and hydroxyl groups on the surface of boron; specifically, the preparation method of modified boron includes the following steps:
[0048] S1. Add boron powder to dichloromethane and ultrasonically disperse for 0.5 to 1 hour to ensure that the boron powder is evenly dispersed in the dichloromethane;
[0049] S2. Add (3-fluoropropyl)trimethoxysilane to the solution obtained in S1 and disperse by ultrasonication for 20-30 min;
[0050] S3. Stir the solution obtained in S2 magnetically at room temperature for 12-24 hours to obtain a mixed solution;
[0051] S4. Wash the mixture obtained from S3 with dichloromethane, centrifuge, and vacuum dry to obtain halogen alkylsilane-functionalized modified boron.
[0052] As attached Figure 1 As shown, in one specific embodiment, XPS depth profiling was used to determine the elemental distribution and thickness of the functionalized layer. The surface layer of the material was removed by Ar sputtering, with one cycle corresponding to approximately 1 nm of surface layer. For FOTS-B, the intensity of F1s decreased rapidly within the first 20 cycles, indicating that the thickness of the FOTS-B functionalized layer was approximately 20 nm.
[0053] In a preferred embodiment, the halogenated alkylsilane is 20% to 30% of the boron mass. An appropriate amount of halogenated alkylsilane can effectively improve the surface properties of the particles while avoiding excessive costs; below this range, the modification effect is insufficient, while above this range, due to the limited reaction sites of boron particles, excessive amounts of modifying reagent are wasted, causing unnecessary losses and increasing costs. Furthermore, higher amounts of halogenated alkylsilane introduce more organohalogens, posing potential risks to the environment and human health.
[0054] Example 1
[0055] This embodiment provides a kerosene gel propellant, the mass ratio and components of which are shown in Table 1.
[0056] Table 1. Mass ratio and composition of the propellant in Example 1
[0057] Formula composition Content / wt.% kerosene 57 FPTS-B 40 polyurethane 3
[0058] This embodiment also provides a method for preparing the above-mentioned kerosene gel propellant, including the following steps:
[0059] At 70°C, polyurethane gelling agent and FPTS-B were added to kerosene and stirred rapidly at 1200 rpm for 15 min until the solution was uniformly mixed. The mixture was then allowed to stand at room temperature until it gelled, thus obtaining a kerosene gel propellant containing modified boron.
[0060] The propellant provided in this embodiment has a combustion efficiency of 98.2%, a dynamic stability of 98.32%, and can be stored stably for one year under static conditions.
[0061] Example 2
[0062] This embodiment provides a kerosene gel propellant, the mass ratio and components of which are shown in Table 2.
[0063] Table 2. Mass ratio and composition of propellant in Example 2
[0064]
[0065]
[0066] This embodiment also provides a method for preparing the above-mentioned kerosene gel propellant, including the following steps:
[0067] At 80°C, gelatin and CPTS-B were added to kerosene and stirred rapidly at 1500 rpm for 10 minutes until the solution was uniformly mixed. The mixture was then allowed to stand at room temperature until it gelled, thus obtaining a kerosene gel propellant containing modified boron.
[0068] The propellant provided in this embodiment has a combustion efficiency of 97.4%, a dynamic stability of 99.12%, and can be stored stably for one year under static conditions.
[0069] Example 3
[0070] This embodiment provides a kerosene gel propellant, the mass ratio and components of which are shown in Table 3.
[0071] Table 3. Mass ratio and composition of propellant in Example 3
[0072] Formula composition Content / wt.% kerosene 46.5 TFPTS-B 50 Polyvinyl alcohol 3 Hydroxyethyl cellulose 1
[0073] This embodiment also provides a method for preparing the above-mentioned kerosene gel propellant, including the following steps:
[0074] At 80°C, polyvinyl alcohol, hydroxyethyl cellulose and TFPTS-B gelling agents were added to kerosene. The mixture was stirred rapidly at 1700 rpm for 25 min until the solution was homogeneous. The mixture was then allowed to stand at room temperature until it gelled, thus obtaining a kerosene gel propellant containing modified boron.
[0075] The propellant provided in this embodiment has a combustion efficiency of 95.7%, a dynamic stability of 99.69%, and can be stored stably for one year under static conditions.
[0076] Example 4
[0077] This embodiment provides a kerosene gel propellant, the mass ratio and components of which are shown in Table 4.
[0078] Table 4. Mass ratio and composition of propellant in Example 4
[0079] Formula composition Content / wt.% kerosene 42.4 FOTS-B 55 polyamide resin 2.6
[0080] This embodiment also provides a method for preparing the above-mentioned kerosene gel propellant, including the following steps:
[0081] At 55°C, polyamide resin and FOTS-B gelling agent were added to kerosene. The mixture was stirred rapidly at 2000 rpm for 20 minutes until the solution was homogeneous. The mixture was then allowed to stand at room temperature until it gelled, thus obtaining a kerosene gel propellant containing modified boron.
[0082] The propellant provided in this embodiment has a combustion efficiency of 96%, a dynamic stability of 99.47%, and can be stored stably for one year under static conditions.
[0083] Example 5
[0084] This embodiment provides a kerosene gel propellant, the mass ratio and components of which are shown in Table 5.
[0085] Table 5. Mass ratio and composition of the propellant in Example 5
[0086] Formula composition Content / wt.% kerosene 37.2 FDTS-B 60 Hydroxyethyl cellulose 2.8
[0087] This embodiment also provides a method for preparing the above-mentioned kerosene gel propellant, including the following steps:
[0088] At 60°C, hydroxyethyl cellulose gelling agent and FDTS-B were added to kerosene. The mixture was stirred rapidly at 2300 rpm for 30 min until homogeneous. The mixture was then allowed to stand at room temperature until gelation was achieved, thus obtaining a kerosene gel propellant containing modified boron.
[0089] The propellant provided in this embodiment has a combustion efficiency of 97%, a dynamic stability of 99.77%, and can be stored stably for one year under static conditions.
[0090] Comparative Example 1
[0091] This comparative example provides a kerosene gel propellant without the addition of halogenated alkyl functionalized boron, and the mass ratio and components are shown in Table 6.
[0092] Table 6. Mass ratio components of propellant in Comparative Example 1
[0093] Formula composition Content / wt.% kerosene 57 B 40 polyurethane 3
[0094] The preparation method of the above-mentioned kerosene gel propellant without the addition of halogen alkyl functionalized boron includes the following steps:
[0095] At 70°C, polyurethane gelling agent and B were added to kerosene and stirred rapidly at 1200 rpm for 15 min until the solution was uniformly mixed. The mixture was then allowed to stand at room temperature until it gelled, thus obtaining a kerosene gel propellant containing functionalized boron.
[0096] The propellant provided in this comparative example showed partial sedimentation of particles during gelation, resulting in poor gelation effect. Its dynamic stability was 70.32%, and after standing for half a month, phenomena such as oil separation occurred. Its combustion efficiency was 83.1%.
[0097] Comparative Example 2
[0098] This comparative example provides a kerosene gel propellant without the addition of halogenated alkyl functionalized boron, and the mass ratio and components are shown in Table 7.
[0099] Table 7. Mass ratio components of propellant in Comparative Example 1
[0100] Formula composition Content / wt.% kerosene 42.4 B 55 polyamide resin 2.6
[0101] The preparation method of the above-mentioned kerosene gel propellant without the addition of halogen alkyl functionalized boron includes the following steps:
[0102] At 55°C, gelling agent polyamide resin and B are added to kerosene. The mixture is stirred rapidly at 2000 rpm for 20 minutes until the solution is homogeneous. The mixture is then allowed to stand at room temperature until it gels, thus obtaining kerosene gel propellant.
[0103] The propellant provided in this comparative example showed partial sedimentation of particles during gelation, resulting in poor gelation effect. Its dynamic stability was 76.49%, and after standing for half a month, phenomena such as oil separation occurred. Its combustion efficiency was 80.4%.
[0104] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0105] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.
[0106] The contents not described in detail in this specification are existing technologies known to those skilled in the art.
[0107] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Furthermore, the technical solutions of the various embodiments of this invention can be combined with each other, but only on the basis of being achievable by one of ordinary skill in the art. When a combination of technical solutions is contradictory or impossible to implement, such a combination should be considered non-existent and not within the scope of protection claimed by this invention.
Claims
1. A kerosene gel propellant, characterized in that, The components include the following mass ratios: Kerosene: 37wt.%~68wt.%; Modified boron: 30wt.%~60wt.%; Gelling agent: 2wt.%~5wt.%; The modified boron is a halogenated alkylsilane functionalized boron obtained by chemically combining a halogenated alkylsilane with boron, and the halogenated alkylsilane functionalized boron includes a -BO-Si- architecture.
2. The kerosene gel propellant as described in claim 1, characterized in that, The boron is amorphous boron powder with a particle size range of 0.5~0.8μm.
3. The kerosene gel propellant as described in claim 1, characterized in that, The halogenated alkylsilanes include alkylsilanes containing fluorine, chlorine, bromine, or iodine.
4. The kerosene gel propellant as described in claim 3, characterized in that, The halogenated alkylsilane includes one of (3-fluoropropyl)trimethoxysilane, (3-chloropropyl)trimethoxysilane, (3-bromopropyl)trimethoxysilane, (3-iodopropyl)trimethoxysilane, (3,3,3-trifluoropropyl)triethoxysilane, 1H,1H,2H,2H-perfluorooctyltriethoxysilane, or 1H,1H,2H,2H-perfluorodecyltriethoxysilane.
5. The kerosene gel propellant as described in claim 4, characterized in that, The halogenated alkylsilane is one of 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane or 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane.
6. The kerosene gel propellant as described in claim 1, characterized in that, The gelling agent includes one or a combination of polyurethane, polyvinyl alcohol, gelatin, polyamide resin and hydroxyethyl cellulose.
7. A method for preparing a kerosene gel propellant as described in any one of claims 1 to 6, characterized in that, Includes the following steps: A gelling agent and modified boron were added to kerosene, stirred evenly, and allowed to stand at room temperature to obtain a kerosene gel propellant containing halogenated alkylsilane functionalized boron.
8. The method for preparing the kerosene gel propellant as described in claim 7, characterized in that, The stirring temperature is 50~80℃, the stirring speed is 1000~2500rpm, the stirring time is 10~30min, and the gelation time is 5~10min.
9. The method for preparing the kerosene gel propellant as described in claim 7, wherein the method for preparing the modified boron comprises the following steps: S1. Add boron powder to dichloromethane and ultrasonically disperse for 0.5~1h; S2. Add a halogenated alkylsilane reagent to the suspension obtained in S1 and disperse it by ultrasonication for 20-30 min; S3. Stir the suspension obtained in S2 magnetically at room temperature for 12-24 hours to obtain a mixture; S4. Wash the mixture obtained from S3 with dichloromethane, centrifuge, and vacuum dry to obtain halogenated alkylsilane functionalized boron.
10. The method for preparing the kerosene gel propellant according to any one of claims 7 to 9, characterized in that, The mass of the halogenated alkylsilane is 20% to 30% of the mass of boron.