High-sensitivity moisture-proof ignition composition and preparation method thereof

Abstract

The application discloses a high-sensitivity moisture-proof ignition powder composition and a preparation method thereof. The high-sensitivity moisture-proof ignition powder composition comprises a pyrotechnic agent base, a high-thermal-conductivity inorganic powder and a high-molecular-weight fluorine-containing polymer solution. The high-molecular-weight fluorine-containing polymer solution is used for adsorbing and bonding the pyrotechnic agent base and the high-thermal-conductivity inorganic powder. The high-molecular-weight fluorine-containing polymer is used as an adhesive, the polymer consumption is reduced, and the moisture-proof performance is provided. Meanwhile, the high-thermal-conductivity inorganic solid particles are introduced into the pyrotechnic agent base, the volume shrinkage during drying is reduced, the thermal conductivity is improved, and the sensitivity of the ignition agent is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ignition powder, in particular to a high-sensitivity moisture-proof ignition powder composition and a preparation method thereof. BACKGROUND

[0002] Currently, the mainstream detonator ignition transducer element in the market uses metal bridge wire or bridge band as the electric heating transducer element, and the bridge wire or bridge band is wrapped with sensitive initiating explosive.

[0003] When a pulse current is loaded, the metal bridge wire or bridge band generates heat and warms up, ignites the initiating explosive in contact with it to produce high-temperature flame, and then the high-temperature flame contacts the detonator booster to detonate the detonator; the initiating explosive in the mainstream transducer element uses water-based polymers such as PVA and EVA as adhesives to provide cohesion and molding capability.

[0004] However, the addition of water-based polymers reduces the sensitivity of the explosive on the one hand, and on the other hand, it is easy to absorb moisture, so an additional waterproof layer is needed to avoid the problem of moisture absorption and detonation rejection; in addition, during the drying process of the initiating explosive, air pockets and fine bubbles are easily generated inside, reducing the contact area of the explosive and the metal bridge and increasing the thermal conduction resistance, resulting in an increase in ignition delay and a certain distribution; therefore, a high-sensitivity moisture-proof ignition powder composition and a preparation method thereof are proposed to solve the above problems. SUMMARY

[0005] In order to make up for the shortcomings of the prior art and solve at least one of the above problems, the present application proposes a high-sensitivity moisture-proof ignition powder composition and a preparation method thereof.

[0006] A high-sensitivity moisture-proof ignition powder composition, comprising initiating explosive base, high-thermal-conductivity inorganic powder, and high-molecular-weight fluoropolymer solution; the high-molecular-weight fluoropolymer solution adsorbs and bonds the initiating explosive base and the high-thermal-conductivity inorganic powder.

[0007] A preparation method of a high-sensitivity moisture-proof ignition powder composition, the preparation method comprising the following steps:

[0008] Step S1: Synthesizing a high-molecular-weight fluoropolymer with a number average molecular weight not less than 500,000 and a weight average molecular weight not less than 1,000,000, and preparing a transparent solution with a solid content of 3-5% wt;

[0009] Step S2: Blending the initiating explosive base powder with a d50 particle size of 2-5 microns with the high-molecular-weight fluoropolymer solution, and mechanically stirring to obtain initiating explosive base / fluoropolymer dispersion slurry;

[0010] Step S3: adding high-thermal-conductivity inorganic powder into the pyrotechnic composition base / fluorine-containing polymer dispersion slurry obtained in step S2, the amount of the high-thermal-conductivity inorganic powder being 10-50% wt of the pyrotechnic composition, and then uniformly stirring to obtain a pyrotechnic composition base / high-thermal-conductivity inorganic powder / fluorine-containing polymer dispersion slurry;

[0011] Step S4: dipping and wrapping the pyrotechnic composition base / high-thermal-conductivity inorganic powder / fluorine-containing polymer dispersion slurry obtained in step S3 onto a metal bridge wire or a metal bridge tape, and then heating and drying to obtain a high-sensitivity moisture-proof ignition powder.

[0012] Preferably, in step S1, the high-molecular-weight fluorine-containing polymer is specifically polyperfluoro-octyl methacrylate.

[0013] Preferably, in step S2, the mass ratio of the polymer to the pyrotechnic powder is 0.1-1% wt, and the solvent is selected from high-boiling-point weakly polar solvents, specifically one of octyl acetate and propylene glycol dimethyl ether.

[0014] Preferably, in step S3, the inorganic powder is specifically one of diamond powder, hexagonal boron nitride powder, and corundum powder, and the mesh number is not less than 2000 mesh.

[0015] The present application has the following advantages:

[0016] The present application uses high-molecular-weight fluorine-containing polymer as a binder, reduces the amount of the polymer while providing moisture-proof performance, and introduces high-thermal-conductivity inorganic solid particles into the pyrotechnic composition base, thereby reducing the volume shrinkage during drying, increasing the thermal conductivity, and increasing the sensitivity of the ignition powder. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0018] Figure 1 The preparation method flow chart of one embodiment of the present application;

[0019] Figure 2 The ignition powder slurry component structure schematic diagram of one embodiment of the present application;

[0020] Figure 3 The molecular weight test results of the high-molecular-weight fluorine-containing polymer used in one embodiment of the present application. DETAILED DESCRIPTION

[0021] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present application.

[0022] Embodiment one:

[0023] Please refer to Figures 1-2 As shown in the figure, a high-sensitivity moisture-proof ignition composition includes a pyrotechnic agent base, a high-thermal-conductivity inorganic powder, and a high-molecular-weight fluoropolymer solution; the high-molecular-weight fluoropolymer solution adsorbs and bonds the pyrotechnic agent base and the high-thermal-conductivity inorganic powder.

[0024] A preparation method of a high-sensitivity moisture-proof ignition composition includes the following steps:

[0025] Step S1: Synthesize a high-molecular-weight fluoropolymer with a number average molecular weight of 639,000 and a weight average molecular weight of 2,549,000, and prepare a transparent solution with a solid content of 3% wt;

[0026] Step S2: Mix the pyrotechnic agent base powder with a d50 particle size of 2 microns with the high-molecular-weight fluoropolymer solution, and mechanically stir to obtain a pyrotechnic agent base / fluoropolymer dispersion slurry;

[0027] Step S3: Add a high-thermal-conductivity inorganic powder to the pyrotechnic agent base / fluoropolymer dispersion slurry obtained in step S2, with a dosage of 10% wt of the pyrotechnic agent, and mechanically stir to obtain a pyrotechnic agent base / high-thermal-conductivity inorganic powder / fluoropolymer dispersion slurry;

[0028] Step S4: Dip and wrap the pyrotechnic agent base / high-thermal-conductivity inorganic powder / fluoropolymer dispersion slurry obtained in step S3 onto a metal bridge wire or a metal bridge belt, and heat and dry to obtain a high-sensitivity moisture-proof ignition composition.

[0029] As an embodiment of the present application, in step S1, the high-molecular-weight fluoropolymer is specifically polyperfluorooctyl methacrylate.

[0030] As an embodiment of the present application, in step S2, the mass ratio of the polymer to the powder is 0.1% wt, and the solvent is selected from high-boiling weak polar solvents, specifically one of octyl acetate and propylene glycol dimethyl ether.

[0031] As an embodiment of the present application, in step S3, the inorganic powder is specifically one of diamond powder, hexagonal boron nitride powder, and corundum powder, and the mesh number is 2000.

[0032] Embodiment two

[0033] A high-sensitivity moisture-proof ignition composition, comprising a pyrotechnic agent base, a high-thermal-conductivity inorganic powder, and a high-molecular-weight fluoropolymer solution; the high-molecular-weight fluoropolymer solution adsorbing and bonding the pyrotechnic agent base and the high-thermal-conductivity inorganic powder.

[0034] A preparation method of a high-sensitivity moisture-proof ignition composition, comprising the following steps:

[0035] Step S1: synthesizing a high-molecular-weight fluoropolymer with a number average molecular weight of 639,000 and a weight average molecular weight of 2,549,000, and preparing a transparent solution with a solid content of 4% wt;

[0036] Step S2: mixing pyrotechnic agent base powder with a d50 particle size of 4 microns and the high-molecular-weight fluoropolymer solution, and mechanically stirring to obtain pyrotechnic agent base / fluoropolymer dispersion slurry;

[0037] Step S3: adding high-thermal-conductivity inorganic powder to the pyrotechnic agent base / fluoropolymer dispersion slurry obtained in step S2, with an amount of 25% wt of the pyrotechnic agent, and mechanically stirring to obtain pyrotechnic agent base / high-thermal-conductivity inorganic powder / fluoropolymer dispersion slurry;

[0038] Step S4: dipping and wrapping the pyrotechnic agent base / high-thermal-conductivity inorganic powder / fluoropolymer dispersion slurry obtained in step S3 onto a metal bridge wire or a metal bridge belt, and heating and drying to obtain a high-sensitivity moisture-proof ignition composition.

[0039] As an embodiment of the present application, in step S1, the high-molecular-weight fluoropolymer is specifically polyperfluorooctyl methacrylate.

[0040] As an embodiment of the present application, in step S2, the mass ratio of the polymer to the powder is 0.5% wt, and the solvent is selected from high-boiling weak polar solvents, specifically one of octyl acetate and propylene glycol dimethyl ether.

[0041] As an embodiment of the present application, in step S3, the inorganic powder is specifically one of diamond powder, hexagonal boron nitride powder, and corundum powder, and the mesh number is 2000.

[0042] Embodiment three

[0043] A high-sensitivity moisture-proof ignition composition, comprising a pyrotechnic agent base, a high-thermal-conductivity inorganic powder, and a high-molecular-weight fluoropolymer solution; the high-molecular-weight fluoropolymer solution adsorbing and bonding the pyrotechnic agent base and the high-thermal-conductivity inorganic powder.

[0044] A preparation method of a high-sensitivity moisture-proof ignition powder, comprising the following steps:

[0045] Step S1: a high-molecular-weight fluorine-containing polymer is synthesized, with a number average molecular weight of 639,000, a weight average molecular weight of 2,549,000, and being configured into a transparent solution with a solid content of 5% wt;

[0046] Step S2: a pyrotechnic agent base powder with a d50 particle size of 5 microns is blended with the high-molecular-weight fluorine-containing polymer solution, and mechanical stirring is uniformly performed to obtain a pyrotechnic agent base powder / fluorine-containing polymer dispersion slurry;

[0047] Step S3: high-thermal-conductivity inorganic powder is added to the pyrotechnic agent base powder / fluorine-containing polymer dispersion slurry obtained in step S2, with an amount of 50% wt of the pyrotechnic agent, and mechanical stirring is uniformly performed to obtain a pyrotechnic agent base powder / high-thermal-conductivity inorganic powder / fluorine-containing polymer dispersion slurry;

[0048] Step S4: the pyrotechnic agent base powder / high-thermal-conductivity inorganic powder / fluorine-containing polymer dispersion slurry obtained in step S3 is coated and wrapped onto a metal bridge wire or a metal bridge belt, and is heated and dried to obtain a high-sensitivity moisture-proof ignition powder.

[0049] As an embodiment of the present application, in step S1, the high-molecular-weight fluorine-containing polymer is specifically polyperfluorooctyl methacrylate.

[0050] As an embodiment of the present application, in step S2, the mass ratio of the polymer to the powder is 1% wt, and the solvent is selected from high-boiling-point weak-polarity solvents, specifically one of octyl acetate and propylene glycol dimethyl ether.

[0051] As an embodiment of the present application, in step S3, the inorganic powder is specifically one of diamond powder, hexagonal boron nitride powder and corundum powder, and the mesh number is 2,000.

[0052] In order to verify the technical effect of the present application, the inventors compared the moisture resistance of the ignition head obtained by the embodiment of the present application with that of the ignition head of the prior art. 60 of each of the two kinds of ignition heads were taken, of which 30 were used to measure the ignition voltage under room temperature conditions, and the other 30 were placed in an environment of 90°C and 90% relative humidity for 200 hours, then taken out and placed in a room temperature environment for 2 hours, and the ignition voltage was measured. The data is shown in Table 1.

[0053] Table 1 Comparison of moisture resistance of ignition heads of the present application and the prior art

[0054]

[0055] From the data in Table 1, it can be seen that the moisture-proof performance of the ignition head manufactured by the present application is superior to that of the ignition head of the prior art. After the damp-heat aging test, the ignition voltage remains unchanged; while the ignition voltage of the ignition head of the prior art increases significantly after the damp-heat aging.

[0056] Specifically, the high-molecular-weight fluorine-containing polymer provides moisture-proof performance and cohesive molding capability, while reducing the polymer usage; the high-thermal-conductivity inorganic powder does not melt or dissolve during the slurry preparation and drying process, reduces the volume shrinkage during the drying process, and additionally improves the thermal conductivity of the dry slurry and the sensitivity of the propellant; the high-molecular-weight polymer can form more physical entanglements among each other, thus being able to reduce the usage while providing sufficient cohesive force.

[0057] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily mean the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0058] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only illustrative of the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application.

Claims

1. A method for preparing a high-sensitivity moisture-proof ignition composition, characterized in that: The preparation method comprises the following steps: ​ Step S1: synthesizing a high molecular weight fluorine-containing polymer with a number average molecular weight of not less than 500,000 and a weight average molecular weight of not less than 1,000,000 and preparing a transparent solution with a solid content of 3-5%wt; Step S2: mixing the explosive base powder with a d50 particle size of 2-5 microns and the high molecular weight fluorine-containing polymer solution to obtain an explosive base powder, fluorine-containing polymer dispersion slurry by mechanical stirring; Step S3: adding an inorganic powder with a high thermal conductivity to the explosive base powder, fluorine-containing polymer dispersion slurry obtained in step S2, the amount of the inorganic powder being 10-50%wt of the mass of the explosive base powder, and obtaining an explosive base powder, inorganic powder with a high thermal conductivity, fluorine-containing polymer dispersion slurry by mechanical stirring; Step S4: dipping and wrapping the explosive base powder, inorganic powder with a high thermal conductivity, fluorine-containing polymer dispersion slurry obtained in step S3 onto a metal bridge wire or a metal bridge belt, and heating and drying to obtain a high-sensitivity moisture-proof ignition powder; In step S1, the high molecular weight fluorine-containing polymer is specifically polyperfluorooctyl methacrylate; In step S2, the mass ratio of the polymer to the explosive powder is 0.1-1%wt, and the solvent is selected from high-boiling weak polar solvents, specifically one of octyl acetate and propylene glycol dimethyl ether; In step S3, the inorganic powder is specifically one of diamond powder, hexagonal boron nitride powder and corundum powder, and the mesh number is not less than 2000 mesh.

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