Firework propellant containing fluorine binder and preparation method of firework propellant

Abstract

The invention discloses a firework propellant containing a fluorine binder and a preparation method of the firework propellant, and belongs to the technical field of firework propellant composite materials. The preparation method comprises the following steps: dissolving Fe3O4, CuO and polyvinylpyrrolidone into a mixed solution; dissolving the RDX in an acetone solution, and adding the mixed solution to recrystallize and separate out the RDX to obtain a modified RDX explosive; under the protection of inert atmosphere, mixing aluminum powder, magnesium powder and boron powder to obtain active metal powder; adding polytetrafluoroethylene powder, modified RDX explosive and active metal powder to obtain premixed composite powder; and adding a binder fluororubber and polyvinylidene fluoride into ethyl acetate, mixing, adding the premixed composite powder, mixing, and granulating. According to the fluorine-containing binder, the burning speed of a firework propellant system can be controlled, the fluorine-containing binder has good compatibility with an energetic material system, and the product has the advantages of being free of sulfur and nitrogen, slight in smoke, resistant to high temperature, high in safety and the like.

Description

Technical Field

[0001] The invention relates to a firework propellant containing a fluorine binder and a preparation method thereof, belonging to the technical field of firework propellant composite materials. Background Art

[0002] Polymer fluorine-rich oxidants and active metals are mixed in a certain proportion and granulated to form self-sustaining active reaction materials. They have good compatibility with combustibles, additives, emulsifiers, foaming agents and other substances commonly used in industrial explosives, and have excellent long-term storage performance. They are a new type of insensitive energetic material with good application prospects. However, the only drawback is that since the system does not contain explosive groups such as nitro and nitroso, the explosion capacity and explosion speed of the reaction system are relatively weaker than those of nitro explosives, showing limited intensity and work capacity. The combination of high-energy explosives with polymer fluorine-rich oxidants-active metal systems can, on the one hand, significantly reduce the sensitivity of the propellant and improve safety performance; on the other hand, it can improve the detonation performance of the propellant and enhance the viewing quality of fireworks.

[0003] The molding and granulation process of fireworks propellants puts forward higher performance requirements for the binder system, which promotes the continuous development of binders. Fluorinated polymers are a special type of energetic binder. The polymer itself does not carry energetic groups, but has strong advantages over other hydrocarbon polymers. Fluorocarbons have a high density, and the density and performance of propellant components containing fluorocarbons also increase accordingly; fluorides can be used as oxidants to increase the oxygen balance of the entire mixed propellant components, further improving the performance of the propellant. Using fluorinated polymers as adhesives and transition metal oxides as burning rate regulators to develop a high-energy explosive and polymer-rich fluorine-oxidant-based high-detonation-velocity fireworks propellant will significantly improve the comprehensive performance and application potential of the propellant. Summary of the invention

[0004] The present invention relates to a firework propellant containing a fluorine binder and a preparation method thereof. The high-energy explosive RDX is compounded with a polymer fluorine-rich oxidant-active metal system to obtain a firework propellant with both low sensitivity and high explosion heat performance, and a fluorinated polymer is used as a binder to improve the compatibility of the propellant components. A transition metal oxide is used to adjust the burning rate of the propellant, thereby achieving the characteristics of high explosion heat, low sensitivity, green environmental protection and adjustable performance of the firework propellant.

[0005] The present invention is achieved through the following technical solutions.

[0006] A method for preparing a firework propellant containing a fluorine binder, comprising premixing and granulation;

[0007] The premixing comprises the following steps:

[0008] (1.1) The transition metal oxide Fe 3 O4 CuO and polyvinyl pyrrolidone (PVP) are added into deionized water in a mass ratio of 1:0.5-1.5:0.5-1, and ultrasonically dispersed for 1-2 hours to obtain a mixed solution;

[0009] (1.2) After completely dissolving cyclotrimethylene trinitramine RDX in an acetone solution, adding the mixed solution obtained in step (1.1) to allow RDX to recrystallize and precipitate, and obtaining a transition metal oxide-modified high-energy RDX explosive through filtering, washing, and drying;

[0010] (1.3) Under the protection of an inert atmosphere, 20 to 30 parts of aluminum powder, 10 to 15 parts of magnesium powder, and 5 to 10 parts of boron powder are mixed in a V-type mixer according to their weight ratio for 1 to 2 hours to obtain a mixture of active metal powders;

[0011] (1.4) According to the mass ratio, 30 to 50 parts of polytetrafluoroethylene powder, 10 to 15 parts of the modified RDX explosive obtained in step (1.2), and 30 to 40 parts of the active metal powder obtained in step (1.3) are dried and placed in a planetary ball mill at a speed of 500 r / min for 2 to 3 hours to obtain a premixed composite powder;

[0012] The granulation comprises the following steps:

[0013] (2.1) Add 1 to 5 parts of a binder fluororubber and 1 to 5 parts of polyvinylidene fluoride to ethyl acetate according to their weight proportions, and stir at 80 to 100° C. for 1 to 2 hours to obtain a mixed solution;

[0014] (2.2) adding the premixed composite powder to the mixed solution obtained in step (2.1), stirring and mixing thoroughly to obtain a fluorine-containing binder-coated fireworks propellant dispersion;

[0015] (2.3) The dispersion obtained in step (2.2) is extruded and granulated by a granulator, and the obtained granules are dried to obtain the final fluorine-containing binder fireworks propellant.

[0016] The particle sizes of the aluminum powder, magnesium powder and boron powder are 10 to 75 μm.

[0017] The drying temperature of step (2.3) is 60-80°C.

[0018] The firework propellant containing fluorine binder obtained by the invention has an impact sensitivity of 8% to 4% and a friction sensitivity of 6% to 2%.

[0019] The present invention has the beneficial effects:

[0020] (1) The fireworks propellant obtained by the present invention has the characteristic of adjustable burning rate, which improves the combustion performance of the fireworks propellant. 3 O4 The d orbital in the valence electron layer of CuO is easy to gain or lose electrons, so the addition of transition metal oxides in fireworks propellants promotes electron transfer during the reaction, converting Fe 3 O 4 The use of CuO in combination with high-energy explosive RDX intensifies the thermal decomposition reaction of the oxidant, thereby improving the combustion performance of the fireworks propellant. 3 O 4 The content of CuO can adjust the interaction of local atoms on its surface, making the catalytic activity adjustable and controllable.

[0021] (2) The fireworks propellant obtained by the present invention has the characteristics of easy detonation, high energy, safety and reliability. The high-energy explosive RDX is combined with a polymer fluorine-rich oxidant-active metal system so that the fireworks propellant has the advantages of both high-energy explosives and active materials. Compared with the high-energy explosive RDX, the fireworks propellant obtained by the present invention uses polytetrafluoroethylene and active metal powder as a matrix. When subjected to mechanical shock and thermal action, it shows obvious insensitivity and is highly safe during production, storage, transportation and use. Compared with the polymer fluoride propellant system, the present invention introduces the high-energy explosive RDX to solve the problem of harsh reaction conditions between fluorides and active metals and poor combustion performance. The combustion heat of the new fireworks propellant obtained by the present invention is ≥9000J·g -1 , burning speed ≤1.0cm·s -1 , mechanical sensitivity ≤8%, not only has a higher energy level, but also has the characteristics of environmental friendliness and high safety.

[0022] (3) The present invention uses a fluorine-containing binder for granulation, which improves the compatibility between the components of the propellant system. The fireworks propellant obtained by the present invention uses RDX, polytetrafluoroethylene, and active metal powder as the main matrix materials, and is doped with a variety of functional additives, so it puts forward higher requirements for the compatibility of the various components in the system. The fluorine-containing binder is a polymer binder with relatively good comprehensive performance. Introducing it into the propellant for granulation can effectively meet the compatibility issues of the propellant system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a graph of impact sensitivity data of the fireworks propellants obtained based on Examples 1 to 5.

[0024] Figure 2 This is a graph showing the friction sensitivity data of the fireworks propellants obtained in Examples 1 to 5. DETAILED DESCRIPTION

[0025] In order to have a clearer understanding of the technical features of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0026] Example 1

[0027] (1) Transition metal oxide Fe 3 O 4 CuO and polyvinyl pyrrolidone (PVP) were added into deionized water at a mass ratio of 1:0.5:1 and ultrasonically dispersed for 1 h to obtain a mixed solution;

[0028] (2) after completely dissolving cyclotrimethylene trinitramine (RDX) in an acetone solution, adding the mixed solution obtained in step (1) to allow RDX to recrystallize and precipitate, filtering, washing, and drying to obtain a modified RDX explosive;

[0029] (3) Under the protection of an inert atmosphere, 20 parts of aluminum powder, 15 parts of magnesium powder, and 5 parts of boron powder were mixed in a V-type mixer for 1 hour to obtain a mixture of active metal powders;

[0030] (4) adding 30 parts of polytetrafluoroethylene powder, 15 parts of modified RDX explosive, and 30 parts of active metal powder, and then drying them and placing them in a planetary ball mill at a speed of 500 r / min for 2 h to obtain a premixed composite powder;

[0031] (5) Add 1 part of a binder fluororubber and 5 parts of polyvinylidene fluoride into ethyl acetate, stir at 80° C. for 1 hour to obtain a mixed solution, then add the premixed composite powder and mix evenly to obtain a fireworks propellant dispersion, and extrude and granulate it through a granulator to obtain a fireworks propellant product.

[0032] Example 2

[0033] (1) Transition metal oxide Fe 3 O 4 CuO and polyvinylpyrrolidone (PVP) were added into deionized water at a mass ratio of 1:1.5:0.5, and ultrasonically dispersed for 2 h to obtain a mixed solution;

[0034] (2) after completely dissolving cyclotrimethylene trinitramine (RDX) in an acetone solution, adding the mixed solution obtained in step (1) to allow RDX to recrystallize and precipitate, filtering, washing, and drying to obtain a modified RDX explosive;

[0035] (3) Under inert atmosphere, 30 parts of aluminum powder, 10 parts of magnesium powder, and 10 parts of boron powder were mixed in a V-type mixer for 1 hour to obtain a mixture of active metal powders;

[0036] (4) adding 50 parts of polytetrafluoroethylene powder, 10 parts of modified RDX explosive, and 40 parts of active metal powder, and then drying them and placing them in a planetary ball mill at a speed of 500 r / min for 3 hours to obtain a premixed composite powder;

[0037] (5) Add 5 parts of a binder fluororubber and 1 part of polyvinylidene fluoride into ethyl acetate, stir at 100° C. for 2 h to obtain a mixed solution, then add the premixed composite powder and mix evenly to obtain a fireworks propellant dispersion, and extrude and granulate it through a granulator to obtain a fireworks propellant product.

[0038] Example 3

[0039] (1) Transition metal oxide Fe 3 O 4 CuO and polyvinyl pyrrolidone (PVP) were added into deionized water at a mass ratio of 1:1:0.5 and ultrasonically dispersed for 2 h to obtain a mixed solution;

[0040] (2) after completely dissolving cyclotrimethylene trinitramine (RDX) in an acetone solution, adding the mixed solution obtained in step (1) to allow RDX to recrystallize and precipitate, filtering, washing, and drying to obtain a modified RDX explosive;

[0041] (3) Under inert atmosphere, 25 parts of aluminum powder, 12 parts of magnesium powder, and 8 parts of boron powder were mixed in a V-type mixer for 1 hour to obtain a mixture of active metal powders;

[0042] (4) adding 40 parts of polytetrafluoroethylene powder, 10 parts of modified RDX explosive, and 35 parts of active metal powder, and then drying them and placing them in a planetary ball mill at a speed of 500 r / min for 2 h to obtain a premixed composite powder;

[0043] (5) Add 3 parts of a binder fluororubber and 2 parts of polyvinylidene fluoride into ethyl acetate, stir at 100° C. for 2 h to obtain a mixed solution, then add the premixed composite powder and mix evenly to obtain a fireworks propellant dispersion, which is extruded and granulated by a granulator to obtain a fireworks propellant product.

[0044] Example 4

[0045] (1) Transition metal oxide Fe 3 O 4 CuO and polyvinyl pyrrolidone (PVP) were added into deionized water at a mass ratio of 1:1:1 and ultrasonically dispersed for 2 h to obtain a mixed solution;

[0046] (2) after completely dissolving cyclotrimethylene trinitramine (RDX) in an acetone solution, adding the mixed solution obtained in step (1) to allow RDX to recrystallize and precipitate, filtering, washing, and drying to obtain a modified RDX explosive;

[0047] (3) Under inert atmosphere, 25 parts of aluminum powder, 15 parts of magnesium powder, and 5 parts of boron powder were mixed in a V-type mixer for 1 hour to obtain a mixture of active metal powders;

[0048] (4) adding 30 parts of polytetrafluoroethylene powder, 15 parts of modified RDX explosive, and 35 parts of active metal powder, and then drying them and placing them in a planetary ball mill at a speed of 500 r / min for 2 h to obtain a premixed composite powder;

[0049] (5) Add 3 parts of a binder fluororubber and 2 parts of polyvinylidene fluoride into ethyl acetate, stir at 100° C. for 2 h to obtain a mixed solution, then add the premixed composite powder and mix evenly to obtain a fireworks propellant dispersion, which is extruded and granulated by a granulator to obtain a fireworks propellant product.

[0050] Example 5

[0051] (1) Transition metal oxide Fe 3 O 4 CuO and polyvinyl pyrrolidone (PVP) were added into deionized water at a mass ratio of 1:1:1 and ultrasonically dispersed for 2 h to obtain a mixed solution;

[0052] (2) after completely dissolving cyclotrimethylene trinitramine (RDX) in an acetone solution, adding the mixed solution obtained in step (1) to allow RDX to recrystallize and precipitate, filtering, washing, and drying to obtain a modified RDX explosive;

[0053] (3) Under inert atmosphere, 25 parts of aluminum powder, 15 parts of magnesium powder, and 10 parts of boron powder were mixed in a V-type mixer for 1 hour to obtain a mixture of active metal powders;

[0054] (4) adding 30 parts of polytetrafluoroethylene powder, 10 parts of modified RDX explosive, and 35 parts of active metal powder, and then drying them and mixing them in a planetary ball mill at a speed of 500 r / min for 2 h to obtain a premixed composite powder;

[0055] (5) Add 5 parts of a binder fluororubber and 3 parts of polyvinylidene fluoride into ethyl acetate, stir at 90° C. for 2 h to obtain a mixed solution, then add the premixed composite powder and mix evenly to obtain a fireworks propellant dispersion, and extrude and granulate the dispersion using a granulator to obtain a fireworks propellant product.

[0056] The impact sensitivity and friction sensitivity of the fireworks propellants obtained in Examples 1 to 5 are as follows: Figure 1 and Figure 2 As shown, the explosion heat and combustion heat parameters are listed in Table 1.

[0057] Table 1 Explosion heat and combustion heat parameters of fireworks propellants of Examples 1 to 5

[0058] Example Example 1 Example 2 Example 3 Example 4 Example 5 <![CDATA[Calorific value of detonation (J·g -1 )]]> 9232 9230 9014 8992 9006 <![CDATA[Calorific value of combustion (J·g -1 )]]> 13875 13452 12453 13420 12378

[0059] The impact sensitivity of the fireworks propellant obtained by the invention is not higher than 8%, and the friction sensitivity is not higher than 6%, showing excellent insensitivity characteristics and having high safety.

Claims

1. A method for preparing a fireworks propellant containing a fluorine binder, characterized in that: Including premixing and granulation; The premixing comprises the following steps: (1.1) adding transition metal oxide Fe3O4, CuO and polyvinyl pyrrolidone PVP in a mass ratio of 1:0.5-1.5:0.5-1 into deionized water, and ultrasonically dispersing for 1-2 hours to obtain a mixed solution; (1.2) After completely dissolving cyclotrimethylene trinitramine RDX in an acetone solution, adding the mixed solution obtained in step (1.1) to allow RDX to recrystallize and precipitate, and obtaining a transition metal oxide-modified high-energy RDX explosive through filtering, washing, and drying; (1.3) Under inert atmosphere, 20 to 30 parts by weight of aluminum powder, 10 to 15 parts by weight of magnesium powder, and 5 to 10 parts by weight of boron powder are mixed in a V-type mixer for 1 to 2 hours to obtain a mixture of active metal powders; (1.4) According to the mass ratio, 30 to 50 parts of polytetrafluoroethylene powder, 10 to 15 parts of the modified RDX explosive obtained in step (1.2), and 30 to 40 parts of the active metal powder obtained in step (1.3) are dried and placed in a planetary ball mill at a speed of 500 r / min for 2 to 3 hours to obtain a premixed composite powder; The granulation comprises the following steps: (2.1) Add 1 to 5 parts of a binder fluororubber and 1 to 5 parts of polyvinylidene fluoride to ethyl acetate according to their weight proportions, and stir at 80 to 100° C. for 1 to 2 hours to obtain a mixed solution; (2.2) adding the premixed composite powder to the mixed solution obtained in step (2.1), stirring and mixing thoroughly to obtain a fluorine-containing binder-coated fireworks propellant dispersion; (2.3) The dispersion obtained in step (2.2) is extruded and granulated by a granulator, and the obtained granules are dried to obtain the final fluorine-containing binder firework propellant.

2. The method for preparing a fireworks propellant containing a fluorine binder according to claim 1, characterized in that: The particle sizes of the aluminum powder, magnesium powder and boron powder are 10 to 75 μm.

3. A firework propellant containing fluorine binder and a preparation method thereof according to claim 1, characterized in that: The drying temperature of step (2.3) is 60-80°C.

4. A firework propellant containing a fluorine binder obtained according to the preparation method of claims 1 to 5.

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