Propellant composition

Abstract

To provide a propellant composition that does not use nitroglycerin, which is difficult to handle safely, and that has a combustion temperature and low pressure index suitable for the application. [Solution] A propellant composition characterized by containing the following components: (a) nitrocellulose (NC): 15% by mass or more; (b) cyclotrimethylenetrinitramine (RDX): 1% by mass or more and 45% by mass or less; (c) nitroguanidine (NQ): 15% by mass or more and 60% by mass or less; (d) energy plasticizer other than nitroglycerin: 5% by mass or more and less than 15% by mass; and (e) additive as an optional component: 5% by mass or less; and having Q = {mass% of component (b) + mass% of component (d)} ÷ {mass% of component (c)} of 0.1 or more and 3.0 or less, and satisfying the following conditions: (i) component (b) is 24% by mass or less, or (ii) component (b) is greater than 24% by mass and the sum of component (b) and component (c) is greater than 58% by mass.

Description

[Technical Field]

[0001] The present invention relates to a propellant composition that does not use nitroglycerin. More specifically, the present invention relates to a novel propellant composition that does not use nitroglycerin, which is difficult to handle safely, and has an energy density, combustion temperature, and low pressure index suited to the application. [Background technology]

[0002] Conventionally, typical propellant compositions for artillery consist of three components: an energy plasticizer, nitrocellulose (NC), and nitroguanidine (NQ), or four components including a high-energy agent such as the cyclic nitramine compound cyclotrimethylenetrinitramine (RDX) or cyclotetramethylenetetranitramine (HMX), with small amounts of other additives such as stabilizers, anti-flammants, and brighteners. Nitroglycerin, which has high energy and plasticity, is widely used as the energy plasticizer. However, nitroglycerin is highly sensitive, posing a major problem as it requires careful handling at every stage of production, storage, transportation, and processing. To address the safety issues associated with nitroglycerin, manufacturing propellants without nitroglycerin is an effective approach. However, simply removing nitroglycerin makes it difficult to maintain the necessary combustion performance as a propellant. Therefore, there is a need to develop propellant compositions that maintain combustion performance while being free of nitroglycerin.

[0003] When attempting to replace nitroglycerin, it is effective to combine a safer energy plasticizer with a lower energy level than nitroglycerin with a high-energy, relatively safe cyclic nitramine compound.

[0004] It is known that explosives, primarily composed of cyclic nitramine compounds, exhibit high pressure indexes in their combustion properties. This is thought to be because the rate-limiting reaction is not a solid-phase reaction, but rather a reaction occurring in a gaseous state slightly away from the combustion surface, making it more susceptible to pressure influences. The pressure index referred to here is given by the following formula: r = a × P n This is the value of n in the formula {wherein r is the combustion rate (cm / sec), a is a coefficient, P is the pressure (MPa), and n is the pressure index.}. Although it varies depending on the design and intended use of the gun, a lower pressure index is generally preferable.

[0005] Non-patent document 1 below describes a relationship between the particle size of RDX and the pressure index, stating that the pressure index tends to decrease as the particle size decreases.

[0006] Patent Document 1 below describes a propellant composition using a cyclic nitramine compound with a uniform particle size. However, in order to obtain high energy, this propellant composition contains a large amount of the cyclic nitramine compound, which is a factor that increases the pressure index. Furthermore, Patent Document 2 discloses a nitramine-based propellant composition comprising cyclotrimethylenetrinitramine (RDX), nitrocellulose (NC), nitroguanidine (NQ), and an energy plasticizer. This propellant composition is characterized by its low combustion temperature and high handling safety. However, this propellant composition, like the previous one, contains a large amount of cyclic nitramine compounds, which are factors that increase the pressure index. To reduce the pressure index of the propellant composition, it is necessary to reduce the content of cyclic nitramine compounds.

[0007] In the invention described in Patent Document 3 below, the RDX content is specified as 25-35% by mass. However, while Patent Document 3 describes the combustion temperature, it does not describe the particle size of the cyclic nitramine compound necessary to obtain an appropriate pressure index for the propellant composition, and therefore it is not possible to determine the design range of the propellant based on this.

[0008] Patent Document 4 describes a propellant composition comprising (a) nitrocellulose, (b) an active plasticizer having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group, (c) nitroguanidine, and (d) a cyclic nitramine compound, characterized in that the content of component (a) is 20 to 55% by mass of the entire propellant composition, the content of component (b) is 15 to 30% by mass, the total content of components (c) and (d) is 20 to 60% by mass, and the ratio of the content of component (c) to the content of component (d) is 1.0 or more. However, further improvement in the balance of combustion performance was desired. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Patent No. 4471042 [Patent Document 2] Patent No. 5318342 [Patent Document 3] Patent No. 5304327 [Patent Document 4] Patent No. 6285528 [Non-patent literature]

[0010] [Non-Patent Document 1] Propellants,Explosives,Pyrotechnics,26,226-228,2001 [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] In view of the above-mentioned prior art level, the problem to be solved by the present invention is to provide a propellant composition that does not use nitroglycerin which is difficult to handle safely, and has a combustion temperature suitable for use and a low pressure index.

Means for Solving the Problem

[0012] In order to solve the above problems, the inventors of the present application have intensively studied the combustion data of the propellants prototyped so far by multivariate analysis, and repeated prototyping and conducted actual verification. As a result, they unexpectedly found that the above problems can be solved by the following configuration, and thus completed the present invention.

[0013] That is, the present invention is as follows. [1] The following components: (a) Nitrocellulose (NC): 15% by mass or more; (b) Cyclotrimethylenetrinitramine (RDX): 1% by mass or more and 45% by mass or less; (c) Nitroguanidine (NQ): 15% by mass or more and 60% by mass or less; (d) An energy plasticizer other than nitroglycerin having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group: 5% by mass or more and less than 15% by mass; and (e) An additive as an optional component: less than 5% by mass; containing, and The Q value obtained by Q = {mass% of component (b) + mass% of component (d)} ÷ {mass% of component (c)} is 0.1 or more and 3.0 or less, and Any one of the following conditions (i) or (ii): (i) The component (b) RDX is 24% by mass or less, or (ii) The component (b) RDX is more than 24% by mass, and the total of the component (b) RDX and the (c) NQ is more than 58% by mass, A propellant composition characterized by satisfying. [2] The propellant composition according to [1], wherein component (b)RDX is 17% by mass or more and 24% by mass or less. [3] The propellant composition according to [1] or [2], wherein the Q value is 0.5 or more and 1.6 or less. [4] The propellant composition according to any one of [1] to [3], wherein the component (d) energy plasticizer is diethylene glycol dinitrate (DEGDN). [5] The propellant composition according to [4], wherein component (a) NC is 19% by mass or more and 51% by mass or less, component (c) NQ is 18% by mass or more and 47% by mass or less, component (d) DEGDN which is an energy plasticizer is 7% by mass or more, and component (e) additive is 3% by mass or less. [6] A propellant composition according to any one of [1] to [5] above, wherein the pressure index is 0.94 or less. [7] A propellant composition according to any one of [1] to [6] above, wherein the combustion temperature is 2800K or more and 3000K or less. [8] Energy density during propellant combustion is 1750 J / cm³ 3 More than 1850J / cm 3 The propellant composition according to any of the above [1] to [6], which is as follows:

[0014] [9] The propellant composition according to [1], wherein component (b)RDX is 14% by mass or more and 24% by mass or less.

[10] The propellant composition according to [9], wherein the Q value is 0.5 or more and 0.9 or less.

[11] The propellant composition according to [9] or

[10] , wherein the component (d) energy plasticizer is trimethylol ethane trinitrate (TMETN) or diethylene glycol dinitrate (DEGDN).

[12] The propellant composition according to

[11] , wherein component (a) NC is 26% by mass or less, component (c) NQ is 37% by mass or more and 47% by mass or less, component (d) DEGDN which is an energy plasticizer is 11% by mass or less, and component (e) additive is less than 5% by mass.

[13] A propellant composition according to any one of [9] to

[12] , wherein the pressure index is 0.99 or less.

[14] A propellant composition according to any one of [9] to

[13] , wherein the combustion temperature is 2700K or more and 2850K or less.

[15] Energy density during propellant combustion is 1750 J / cm³ 3 More than 1850J / cm 3 The propellant composition according to any of the above [9] to

[14] , which is as follows:

[0015]

[16] The propellant composition according to [1], wherein component (b)RDX is greater than 24% by mass.

[17] The propellant composition according to

[16] , wherein the Q value is 0.3 or more and 2.1 or less.

[18] The propellant composition according to

[16] or

[17] , wherein the component (d) energy plasticizer is diethylene glycol dinitrate (DEGDN).

[19] The propellant composition according to

[18] , wherein component (a) NC is 21% by mass or less, component (b) RDX is more than 24% by mass and 32% by mass or less, component (c) NQ is 34% by mass or more, component (d) DEGDN which is an energy plasticizer is 13% by mass or less, and component (e) additive is 3% by mass or less.

[20] The propellant composition according to

[18] , wherein component (a) NC is 21% by mass or less, component (b) RDX is 36% by mass or more, component (c) NQ is more than 22% by mass and 26% by mass or less, component (d) DEGDN which is an energy plasticizer is 13% by mass or less, and component (e) additive is 3% by mass or less.

[21] A propellant composition according to any one of

[16] to

[20] , wherein the pressure index is 1.0 or less.

[22] A propellant composition according to any one of

[16] to

[21] , wherein the combustion temperature is 3000K or more and 3200K or less.

[23] Energy density during propellant combustion is 1900 J / cm² 3 More than 2050J / cm 3The propellant composition according to any of the above

[16] to

[22] , which is as follows: [Effects of the Invention]

[0016] The propellant composition according to the present invention exhibits a propellant composition that does not use nitroglycerin, which is difficult to handle safely, and has a combustion temperature and low pressure index suitable for the application. Therefore, it can be widely and safely used in the manufacture, storage, transportation, and processing of explosives. [Modes for carrying out the invention]

[0017] The embodiments of the present invention will be described in detail below. One embodiment of the present invention comprises the following components: (a) Nitrocellulose (NC): 15% by mass or more; (b) Cyclotrimethylenetrinitramine (RDX): 1% to 45% by mass; (c) Nitroguanidine (NQ): 15% to 60% by mass; (d) Energy plasticizers other than nitroglycerin having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group: 5% by mass or more and less than 15% by mass; and (e) Additives as optional components: less than 5% by mass; It contains, The Q value calculated using Q = {mass % of component (b) + mass % of component (d)} ÷ {mass % of component (c)} is between 0.1 and 3.0, and Either of the following conditions (i) or (ii): (i) The component (b)RDX is 24% by mass or less, (ii) The component (b)RDX is greater than 24% by mass, and the sum of the component (b)RDX and the (c)NQ is greater than 58% by mass. This propellant composition is characterized by satisfying the following conditions.

[0018] [Ingredient (a): Nitrocellulose (NC)] (a) The amount of nitrogen in nitrocellulose, which is component (a), is not particularly limited as long as it can be kneaded from the raw materials and molded into the shape of a propellant. From the viewpoint of ensuring energy as a propellant and solubility in the solvent used during manufacturing, the amount of nitrogen in nitrocellulose is preferably 11.0 to 13.5% by mass, and more preferably 12.0 to 13.2% by mass. Furthermore, the content (amount blended) of nitrocellulose, which is component (a), in relation to the entire propellant composition is 15% by mass or more from the viewpoint of mechanical strength. Note that the content of component (a) as referred to here is a value based on the sum of each component from component (a) to component (e) as a standard (100% by mass). The same applies to the content of each component below unless otherwise specified.

[0019] [Ingredient (b): Cyclotrimethylene linitolamine (RDX)] Component (b), cyclotrimethylenetrinitramine (RDX), is a cyclic nitramine compound. To minimize fluctuations in the pressure index under high pressure, it is preferable that the particle size distribution of the cyclic nitramine compound in the propellant is such that 99% by volume of the total cyclic nitramine compound has a particle size of 33 microns (μm) or less, and the average particle size is 9 microns (μm) or less. More preferably, 99% by volume of the total cyclic nitramine compound has a particle size of 32 microns (μm) or less, and the average particle size is 9 microns (μm) or less. Furthermore, the more fine particles with a particle size of 4 microns (μm) or less there are, the lower the fluctuations in the pressure index can be suppressed. For this reason, it is preferable to include particles with a particle size of 4 microns (μm) or less in the total cyclic nitramine compound at 16% by volume or more, and more preferably to include particles with a particle size of 3 microns (μm) or less in the total volume. The average particle size referred to here is the particle size (cumulative median diameter) at the point where the cumulative curve reaches 50% by volume when the total volume of the powder aggregate is taken as 100%.

[0020] Methods for powdering cyclic nitramine compounds include, for example, the methods described in Japanese Patent Publication No. 2802388, Japanese Unexamined Patent Publication No. 2002-179490, Japanese Unexamined Patent Publication No. 2002-179491, International Publication No. 99 / 18050, U.S. Patent No. 4770728, and Japanese Unexamined Patent Publication No. 61-37239. To prevent aggregation of cyclic nitramine compound particles and reduce the particle size distribution, the surface of the powder is preferably coated with nitramine at a rate of 2 or higher, and more preferably at a rate of 3 or higher. The nitramine coating rate here is a value determined by (carbon concentration from propellant raw materials other than RDX) / (carbon concentration of RDX), and can be determined by the method described in Japanese Unexamined Patent Publication No. 2002-179490.

[0021] As mentioned above, the particle size distribution of cyclic nitramine compounds is a volume-based particle size distribution. The particle size distribution of cyclic nitramine compounds can be determined, for example, by dispersing the cyclic nitramine compound in water and measuring it using a laser diffraction particle size analyzer. After removing propellant materials other than the cyclic nitramine compound using a solvent that dissolves them to at least 97% by mass, the particle size distribution is measured using a laser diffraction particle size analyzer. Any solvent that does not dissolve the cyclic nitramine compound but dissolves the propellant materials other than the cyclic nitramine compound and can remove them is acceptable for the particle size distribution measurement.

[0022] Examples of solvents used for the particle size distribution measurement include a mixed solvent of one or more solvents from among warm water, acetone, ethyl acetate, and tetrahydrofuran, and ethanol or methanol. A preferred method is to use a saturated solution in which the cyclic nitramine compound has been pre-dissolved so that the cyclic nitramine compound in the powder or propellant does not dissolve as much as possible, as the solvent. In this solvent, propellant materials other than the cyclic nitramine compound are dissolved in an amount of at least 97% by mass or more, to the extent that it does not affect the particle size distribution measurement of the cyclic nitramine compound. This is then filtered, and the solid residue is dispersed in water or a mixture of water and methanol, or water and a surfactant, using an ultrasonic stirrer or the like. This can then be measured using a laser diffraction particle size distribution analyzer (manufacturer: Nippon Laser Co., Ltd., measurement unit optical system: HELOS KR R7, laser wavelength: 632.8 nm, output: 5 mW, fraunhofer method, wet static dispersion unit: CUVETTE). To select the type and amount of solvent to be used for particle size distribution measurement, it is preferable to perform HPLC analysis or GPC analysis on the filtered solids and / or filtrate to confirm whether propellant materials other than cyclic nitramine compounds have been successfully removed. The RDX content is between 1% by mass and 45% by mass.

[0023] [Component (c): Nitroguanidine (NQ)] The NQ content is between 15% by mass and 60% by mass.

[0024] [Component (d): Energy plasticizers other than nitroglycerin, having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group] Component (d) is an energy plasticizer other than nitroglycerin, having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group. There are no particular restrictions as long as the compound satisfies this condition, but typical examples include butanetriol trinitrate (BTTN), trimethylolethane trinitrate (TMETN), trimethylolpropane trinitrate (TMPTN), diethylene glycol dinitrate (DEGDN), triethylene glycol dinitrate (TEGDN), butanediol dinitrate (BDDN), methylnitratoethylnitramine, nitratoethylnitramines such as ethylnitratoethylnitramine and butylnitratoethylnitramine, and a mixture of bis-2,2-dinitropropyl acetal and bis-2,2-dinitropropyl formal (BDNPA / F), one or more of which can be used. In order to produce a propellant that is more powerful and safer, it is preferable to use one or more selected from diethylene glycol dinitrate (DEGDN), triethylene glycol dinitrate (TEGDN), trimethylolethanethrinite (TMETN), and bis-2,2-dinitropropyl formal mixture (BDNPA / F) as component (d). It is particularly preferable to select diethylene glycol dinitrate (DEGDN), trimethylolethanethrinite (TMETN), or two or more energy plasticizers containing these as component (d). The content of the energy plasticizer is 5% by mass or more and less than 15% by mass.

[0025] [Optional ingredient (e) Additives] The propellant composition of this embodiment may contain any additive component (e) in addition to the components (a) to (d) described above. Common additives used in propellants include combustion rate modifiers (also called slowing agents / coolants), stabilizers, antiflammants, plasticizers, thickeners, antioxidants, and moisture-proofing agents. Among these, it is preferable to use combustion rate modifiers, stabilizers, and antiflammants to individually control the pressure index and combustion temperature. Examples of combustion rate modifiers include phthalate compounds such as dibutyl phthalate (DBP), dinitrotoluene, adipic acid ester compounds, and citrate ester compounds, either individually or in mixtures of two or more of these. Examples of stabilizers include diphenylurea derivatives such as diphenylurea, methyldiphenylurea (acaldite II), ethyldiphenylurea, diethyldiphenylurea (ethylcentralit (ECL)), dimethyldiphenylurea, and methylethyldiphenylurea; diphenylamine derivatives such as diphenylamine and 2-nitrodiphenylamine; phenylurethane derivatives such as ethylphenylurethane and methylphenylurethane; diphenylurethane derivatives such as diphenylurethane; resorcinol, zeolite, etc., either alone or in mixtures of two or more. Other examples of anti-inflammatory agents include potassium sulfate (K2SO4), potassium nitrate, or alkali metal salts such as cryolite. The content of component (e) additive is less than 5% by mass, preferably 4% by mass or less, and more preferably 3% by mass or less.

[0026] [Q value can be calculated using the formula: Q = {mass of component (b) % + mass of component (d) %} ÷ {mass of component (c) %}] The propellant composition of this embodiment has the following formula: The Q value, calculated using the formula Q = {mass % of component (b) + mass % of component (d)} ÷ {mass % of component (c)}, is between 0.1 and 3.0. The inventors of this application, through repeated experiments, found that when the Q value exceeds 3.0 within the composition range shown in claim 1, the pressure index exceeds 1.0. When the Q value exceeds 3.0, the proportion of nitroguanidine, which lowers the pressure index, decreases, while the proportion of RDX and energy plasticizer, which raise the pressure index, increases, resulting in a higher pressure index for the propellant composition. Furthermore, by incorporating a large amount of RDX, which has a high heat output, the combustion temperature increases, and the load on the gun barrel increases. If the Q value is 3.0 or less, the pressure index can be kept below 1.0, which reduces the internal pressure of the gun during firing. This makes it easier to design a gun that achieves the desired muzzle velocity while reducing the load on the barrel. Furthermore, by reducing the RDX content, it is possible to design a composition that is suitable for the combustion temperature. Furthermore, the Q value is particularly preferably 0.3 to 2.1 in order to ensure sufficient explosive power as a propellant while suppressing the pressure index and combustion temperature. The propellant composition of this embodiment makes it possible to achieve both high energy density, a low pressure index, and a suitable combustion temperature. Based on the above, the present invention should be recognized as having technical significance in that it makes it possible to design propellant compositions while adjusting the pressure index using the Q value as an indicator.

[0027] In the propellant composition of this embodiment, in addition to the above conditions, when component (b) RDX is 24% by mass or less, the pressure index and moldability are excellent. The low amount of RDX allows for flexible adjustment of the blend with other components, ensuring freedom in the design of the propellant composition. Furthermore, even when component (b)RDX exceeds 24 mass%, by adjusting the composition so that the sum of (b)RDX and component (c)NQ exceeds 58 mass, it is possible to obtain high energy while maintaining moldability as a propellant and a low pressure index.

[0028] The propellant of the present invention is manufactured by a solvent molding method, in which predetermined amounts of nitrocellulose (NC), nitroguanidine (NQ), cyclotrimethylenetrinitramine (RDX), and other cyclic nitramine compounds, energy plasticizers, and additives are added to a kneading machine (which mixes the raw materials and solvents of each component and kneads them to produce a kneading agent before rolling), and a solvent such as acetone, alcohol, ethyl acetate, or diethyl ether is added in an amount sufficient to dissolve the nitrocellulose. The mixing process is carried out until the raw materials and solvents are uniformly distributed, and then the mixing agent is fed into the press. The kneading agent is fed into a press and compressed at a predetermined pressure. The resulting compressed agent is then cut into the desired shape, air-dried, and dried to obtain the propellant.

[0029] The shape of the propellant in the present invention can be any shape required from a performance standpoint. Examples include columnar propellants, single-hole propellants, 7-hole tubular propellants, hexagonal 7-hole propellants, 19-hole tubular propellants, hexagonal 19-hole propellants, 37-hole tubular propellants, hexagonal 37-hole propellants, rosette 7-hole propellants, rosette 19-hole propellants, rosette 37-hole propellants, rod-shaped propellants, propellants with slits, or rod-shaped propellants such as those shown in U.S. Patent No. 5,251,549, which include radial slits perpendicular to the generatrix of the rod and starting from the outer surface of the rod. [Examples]

[0030] The present invention will be specifically described below with reference to examples and comparative examples. Furthermore, the present invention is not limited to the following embodiments, and can be implemented with various modifications within the scope of its essence. [Manufacturing of propellant] (Manufacturing Example 1) A powder consisting of cyclotrimethylenetrinitramine (RDX) as a cyclic nitramine compound (76% by mass), nitrocellulose (NC) (nitrogen content 12.6%) (23.5% by mass), and ethyl centralitate (ECL) as a stabilizer (0.5% by mass) was prepared by a well-known method (for example, the method described in Japanese Patent Publication No. 2802388).

[0031] (Examples 1-11, Comparative Examples 1-5) Using the powder prepared in Production Example 1, the raw materials were placed in a kneading machine with a mixed solvent of acetone and ethanol to obtain the composition shown in Table 1 below. The mixture was then mixed and kneaded until homogeneous. From there, the known solvent-based rolling method was used to prepare rolling agents with the compositions described in Examples 1-11 and Comparative Examples 1-5. The obtained expandable charge was cut, air-dried, and then used to prepare the propellant. To obtain accurate pressure index data, the shape of the propellant was standardized to a single-hole tubular shape (outer diameter approximately 1 cm, length approximately 1 cm, inner diameter approximately 0.2 cm), rather than a complex shape.

[0032] [Sealed Bomb Test] For the propellants produced, in Examples 1 to 11 and Comparative Examples 1 to 5, 1.5×10 -4 (m 3 ) of the propellant with the dosage adjusted to 1.5×10 5 (g / m 3 ) was placed in the center of a sealed bomb tester of 2.49×10

[0033] [Pressure Index] The maximum pressure generated in the above-mentioned sealed bomb test was 200 - 250 MPa. The pressure (P)-burning rate (r) graph of the propellant calculated from the bomb test results was approximated by the least squares method to the following formula: r = a×P n {In the formula, r is the burning rate (cm / sec), a is the coefficient, P is the pressure (MPa), and n is the pressure index.} and the pressure index was calculated.

[0034] [Combustion Temperature] The combustion temperatures in Examples 1 to 11 and Comparative Examples 1 to 5 were calculated by chemical equilibrium calculation (described in Firearms and Ammunition Technology Handbook P12).

[0035] [Energy Density] For the energy density (J / cm 3 ) in Examples 1 to 11 and Comparative Examples 1 to 5, the following formula: JPEG2026053096000001.jpg689{In the formula, n is the number of moles per gram of combustion product gas, Ro is the universal gas constant (8.31 J / (K·mol)), γ is the specific heat ratio calculated by the above-mentioned chemical equilibrium calculation, T is the constant-pressure adiabatic flame temperature (K), and d is the density (g / cm 3 ) of each component alone at 25°C.} was used to calculate the energy density (the energy value per unit volume of the propellant).

[0036] [Moldability] The ease of molding and cutting (hereinafter collectively referred to as "moldability") of the compressible materials with compositions described in Examples 1-11 and Comparative Examples 1-5 when compressed using a compressor and cut using a cutting machine were evaluated according to the following evaluation criteria. (Evaluation Criteria) ○: It could be compressed using a compression machine, and the compression agent and the through-holes inside were not crushed, allowing it to be easily cut with a cutting machine. △: Although it can be compressed using a compression machine, careful handling is required, such as controlling the compression speed to prevent the internal through-holes from being crushed during compression. ×: It took a long time to compress the material using a compressing machine, and the compressing agent was very brittle, causing handling problems.

[0037] The evaluation results for Examples 1-11 and Comparative Examples 1-5 are shown in Table 1 below. [Table 1]

[0038] In all of the propellants used in Examples 1 to 11, the pressure index was 1.0 or less. Furthermore, these propellants exhibited excellent moldability, and their combustion temperature and energy density were at levels suitable for artillery propellants. Specifically, in Example 1, raw materials were prepared with 20% by mass of NC, 12% by mass of DEGDN, 20% by mass of RDX, 46.2% by mass of NQ, 1.5% by mass of ECL, and 0.3% by mass of Cryolite, so that the Q value was 0.69 and the combustion temperature was 2817K. After mixing, the materials were rolled out. The rolled material maintained its shape after roll-molding and was easy to handle when cutting. The cut material also showed no hole collapse or other problems and could be molded without issue, so the moldability was rated "○". After drying, the completed propellant was weighed and burned in a sealed bomb to check the pressure index and energy density. The results showed a smooth pressure increase, with a pressure index of 0.88 and an energy density of 1805.0 J / cm². 3Therefore, despite its low pressure index, it has a high energy density, making it possible to propel the projectile at a specified velocity while keeping the pressure inside the gun low. Furthermore, it was confirmed to be a good propellant composition that can extend and maintain barrel life due to its relatively low combustion temperature of 2817K. Examples 2-11 also confirmed to be good propellant compositions, similar to Example 1.

[0039] In contrast, in Comparative Example 1, the amount of component (a) was low at 10% by mass, making the mixture prone to collapse before rolling, requiring careful molding. In Comparative Example 2, the Q value was low at 0.08, indicating insufficient energy density required for artillery propellant. In Comparative Example 3, the Q value was high at 4.12, the combustion temperature was high at 3322K, and the pressure index was high at 1.04, resulting in a large load on the gun barrel. Furthermore, for Comparative Examples 4 and 5, which have propellant compositions or Q values ​​outside the range of this embodiment, the pressure index was 1.00 or higher. [Industrial applicability]

[0040] The present invention provides a propellant composition that does not use nitroglycerin, which is difficult to handle safely, and has a combustion temperature and low pressure index suitable for its application. Therefore, it can be widely and safely used in the manufacture, storage, transportation, and processing of explosives.

Claims

1. The following ingredients: (a) Nitrocellulose (NC): 15% by mass or more; (b) Cyclotrimethylenetrinitramine (RDX): 1% by mass or more and 45% by mass or less; (c) Nitroguanidine (NQ): 15% by mass or more and 60% by mass or less; (d) Energy plasticizers other than nitroglycerin having a nitrate ester group, a nitro group, a nitramine group, and / or an azide group: 5% by mass or more and less than 15% by mass; and (e) Additives as optional components: less than 5% by mass; It contains, and The Q value calculated by Q = {mass % of component (b) + mass % of component (d)} ÷ {mass % of component (c)} is between 0.1 and 3.0, and Either condition (i) or (ii) below: (i) The component (b) RDX is 24% by mass or less, (ii) The component (b)RDX is greater than 24% by mass, and the sum of the component (b)RDX and the (c)NQ is greater than 58% by mass. A propellant composition characterized by satisfying the following conditions.

2. The propellant composition according to claim 1, wherein the component (b) RDX is 17% by mass or more and 24% by mass or less.

3. The propellant composition according to claim 1 or 2, wherein the Q value is 0.5 or more and 1.6 or less.

4. The propellant composition according to claim 1 or 2, wherein the component (d) energy plasticizer is diethylene glycol dinitrate (DEGDN).

5. The propellant composition according to claim 4, wherein component (a) NC is 19% by mass or more and 51% by mass or less, component (c) NQ is 18% by mass or more and 47% by mass or less, component (d) DEGDN, which is an energy plasticizer, is 7% by mass or more, and component (e) additive is 3% by mass or less.

6. The propellant composition according to claim 5, wherein the pressure index is 0.94 or less.

7. The propellant composition according to claim 6, wherein the combustion temperature is 2800K or more and 3000K or less.

8. The energy density during propellant combustion is 1750 J / cm². ３ More than 1850J / cm ３ The propellant composition according to claim 7, which is as follows:

9. The propellant composition according to claim 1, wherein the component (b) RDX is 14% by mass or more and 24% by mass or less.

10. The propellant composition according to claim 9, wherein the Q value is 0.5 or more and 0.9 or less.

11. The propellant composition according to claim 9 or 10, wherein the component (d) energy plasticizer is trimethylolethane trinitrate (TMETN) or diethylene glycol dinitrate (DEGDN).

12. The propellant composition according to claim 11, wherein component (a) NC is 26% by mass or less, component (c) NQ is 37% by mass or more and 47% by mass or less, component (d) DEGDN, which is an energy plasticizer, is 11% by mass or less, and component (e) additive is less than 5% by mass.

13. The propellant composition according to claim 12, wherein the pressure index is 0.99 or less.

14. The propellant composition according to claim 13, wherein the combustion temperature is 2700K or more and 2850K or less.

15. The energy density during propellant combustion is 1750 J / cm². ３ More than 1850J / cm ３ The propellant composition according to claim 14, which is as follows:

16. The propellant composition according to claim 1, wherein component (b) RDX is present in an amount of more than 24% by mass.

17. The propellant composition according to claim 16, wherein the Q value is 0.3 or more and 2.1 or less.

18. The propellant composition according to claim 16 or 17, wherein the component (d) energy plasticizer is diethylene glycol dinitrate (DEGDN).

19. The propellant composition according to claim 18, wherein component (a) NC is 21% by mass or less, component (b) RDX is more than 24% by mass and 32% by mass or less, component (c) NQ is 34% by mass or more, component (d) DEGDN, which is an energy plasticizer, is 13% by mass or less, and component (e) additive is 3% by mass or less.

20. The propellant composition according to claim 18, wherein component (a) NC is 21% by mass or less, component (b) RDX is 36% by mass or more, component (c) NQ is more than 22% by mass and 26% by mass or less, component (d) DEGDN, which is an energy plasticizer, is 13% by mass or less, and component (e) additive is 3% by mass or less.

21. The propellant composition according to claim 19 or 20, wherein the pressure index is 1.0 or less.

22. The propellant composition according to claim 19 or 20, wherein the combustion temperature is 3000K or more and 3200K or less.

23. The energy density during propellant combustion is 1900 J / cm². ３ More than 2050J / cm ３ The propellant composition according to claim 19 or 20, which is as follows:

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