JPH10287674A - Production of epsilon-hexanitrohexaazaisowurtzitane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject compound having a high density and a high energy by crystallizing hexanitrohexaazaisowurtzitane by the use of the mixture of a low boiling point good solvent with a low boiling point poor solvent as a solvent. SOLUTION: This method for producing ε-hexanitrohexaazaisowurtzitane (hereinafter referred to as HNIW) comprises dissolving HNIW of the formula: W(NO)6 (W is a hexavalent hexaazaisowurtzitane residue of the formula) in the mixture of a low boiling point good solvent with a low boiling point poor solvent and subsequently evaporating the solvents to deposit the crystals. The HNIW preferably contains one kind of α-HNIW, β-HNIW and γ-HNIW and their mixture as main components. The good solvent includes acetone and methylethylketone, and the poor solvent includes benzene and toluene. The solvent mixture is preferably used in a volume of 5-50 ml per g of the HNIW.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ε-hexanitro containing 90% or more of ε-hexanitrohexaazaisowurtzitane crystal used for improving the performance of a conventional explosive composition. It relates to the production method of hexaazaisoul titanium.

[0002]

2. Description of the Related Art Hexanitrohexaazaisosoultitanium (hereinafter referred to as "HNIW") represented by the following general formula (1) is a high-density and high-energy substance and is promising as a next-generation high-performance explosive material. Have been watched. W (NO ₂ ) ₆ (1) [wherein, W represents a hexavalent hexaazaisowurtzitanium residue represented by the following formula (2). ]

[0003]

Embedded image HNIW has multiple crystal forms, at least α-H
The existence of NIW, β-HNIW, γ-HNIW, and ε-HNIW has been confirmed.

[0004] Among them, ε-HNIW is a crystal form that has received the most attention as an explosive material because it has a high density and is thermodynamically stable. Also, α-HNI
W, β-HNIW or γ-HNIW is known as a metastable crystal. α-HNIW, β-HNIW or a mixture of γ-HNIW and ε-HNIW is xylene,
Alternatively, conversion to ε-HNIW in a solvent such as xylene or bis (2-fluoro-2,2-dinitroethyl) formal to which 10 to 30% acetophenone is added has been reported. Also, γ-HNIW in a solution state
It has been reported that a mixture of ε-HNIW and ε-HNIW is recrystallized to ε-HNIW below 64 ° C.

There is a report that conversion of a mixture of γ-HNIW and ε-HNIW to ε-HNIW is equilibrated within 24 hours when a solvent such as ketones having high solubility in HNIW is added [[ Propellant
s, Explosives, Pyrotechnics
19, 19-25 (1994), Propellant
s, Explosives, Pyrotechnics
19, 63-69 (1994), Propellant
s, Explosives, Pyrotechnics
19, 206-212 (1994)].

However, none of these documents describes specific conditions such as the ratio of HNIW to a solvent. In addition, when a solvent having high solubility is used, there is a problem that the yield decreases. It has been reported that α-HNIW hydrate converts to ε-HNIW at 64 ° C. or lower [Pro
Perlants, Explosives, Pyrot
technics 19, 19-25 (1994)]. There is also a report that ε-HNIW was obtained by a two-solvent crystallization method of chloroform and ethyl acetate [Int. Ann
u. Conf. ICT (1996), 27th (Ene
rgetic Materials), 27.1-2
7.10].

There is also a report that ε-HNIW has been obtained. [Int. Annu. Conf. ICT (199
6), 27th (Energy Material)
ls), 39.1-39.12, Int. Annu. C
onf. ICT (1996), 27th (Energy
tic Materials), 23.1-23.1.
3, Chin. Sci. Bull. (1996), 41
(7), 574-576, Proc. Beijing
Int. Symp. Explos. , 3rd (199
5) 520-525, Proc. Beijing I
nt. Symp. Explos. , 3rd (199
5), 312-314) Proc. INT. Pyrot
ech. Semin. (1996), 22nd, 425
-432]. However, these are all specific ε-H
No description is given of NIW conversion conditions.

[0008]

The HNIW is, for example,
A hexaazaisowurtzitane derivative, in which at least one of them is an acyl group having 1 to 10 carbon atoms, is nitrated with a nitrating agent at six nitrogen atoms of a hexaazaisowurtzitane skeleton serving as a precursor thereof, and is produced. You. As an example, WO
A method disclosed in JP-A-96-23792 is exemplified. However, in these methods, HNIW converts meta-stable crystal α-HNIW or β-HNIW into 90%.
% Or more, and ε-HNI
In order to obtain W, a step of further converting to ε-HNIW is required.

Generally, as a method of depositing crystals using a solvent, there are a slow cooling method in which crystals are precipitated by gradually cooling a solution, and a solvent evaporation method in which crystals are deposited by evaporating the solvent. In either case, the target substance must first be dissolved in a solvent, and a solvent that can dissolve the target substance is used. Further, if necessary, it is used by mixing it with a solvent which does not easily dissolve the target substance.

In the slow cooling method, since a solvent capable of dissolving the target substance remains even after cooling, it is difficult to obtain crystals of the target substance with high yield. Further, in the solvent evaporation method, when a solvent having a high boiling point such as acetophenone is used, it must be kept at a high temperature for a long time to evaporate the solvent, which takes time, and the target substance may be decomposed. If the solvent evaporates quickly, crystals in a thermodynamic metastable state may be precipitated. When the good solvent is not evaporated, HN
The yield is reduced because the IW remains dissolved in the solvent. An object of the present invention is to provide a method for obtaining a thermodynamically stable, high-density substantially ε-HNIW in good yield under such circumstances. The term “substantial ε-HNIW” as used herein refers to a crystal containing 90% or more of ε-HNIW.

[0011]

Means for Solving the Problems The inventors dissolve HNIW with a good solvent having a low boiling point or methanol as a solvent,
In a good solvent having a low boiling point, after adding a poor solvent to form a mixed solvent, the solvent was distilled off at a controlled evaporation rate to precipitate crystals, thereby succeeding in obtaining substantially ε-HNIW. The present invention has been completed. The term "good solvent having a low boiling point" as used herein refers to a solvent having a boiling point of 150 ° C. or less under normal pressure and HNIW of 2 g per 100 g of the solvent at normal temperature and normal pressure.
A solvent capable of dissolving 0 g or more.

The term "poor solvent" as used herein means a solvent which cannot dissolve 1 g or more of HNIW per 100 g of the solvent at normal temperature and normal pressure. The evaporation rate is a numerical value in which the amount of the solvent at the start of evaporation is set to 100, and the amount of decrease in the solvent every hour after the start of the evaporation of the solvent is expressed in percent by weight. That is, the present invention provides a method for dissolving HNIW in a mixed solvent of a good solvent and a poor solvent having a low boiling point, or a methanol solvent to form an HNIW solution, and then evaporating the solvent to precipitate crystals to obtain substantially ε-HNIW. Is provided.

Hereinafter, a method for obtaining substantial ε-HNIW of the present invention will be described. HNIW as starting material of the present invention
May be manufactured by any method. α
HNIW containing one of -HNIW, β-HNIW or γ-HNIW and a mixture thereof can be used. Here, the “main component” refers to a case where at least one of them is contained in 60% or more. As a good solvent having a low boiling point, ketones such as acetone, methyl ethyl ketone, pentanone, hexanone and methyl isobutyl ketone, ethers of tetrahydrofuran, tetrahydropyran, and ethyl acetate are used. These low-boiling good solvents may be used as a mixture of two or more.

As the poor solvent, benzene, toluene, xylene and the like are used. The difference between the solubility parameter of the good solvent and the poor solvent of the low boiling point used here is preferably less than 2. When the difference between the solubility parameters of a good solvent and a poor solvent having a low boiling point is large (for example, in the case of a combination of acetone and heptane), the solution becomes non-uniform upon evaporation of the solvent, and α-HNIW is obtained as a by-product There is. For example, when a mixed solvent of acetone and heptane is used, as the solvent evaporates, the solution becomes non-uniform, and α-HNIW is obtained. As a method of adding the solvent, any method may be used, but a method of adding a poor solvent after dissolving HNIW in a good solvent having a low boiling point is preferable.

When a mixed solvent of a good solvent and a poor solvent having a low boiling point is used, the amount of the solvent is usually 5 to 1 g of HNIW.
It is used in a range of 50 ml, preferably 10 to 40 ml. When the amount of the solvent is less than 5 ml, the solution becomes non-uniform during the evaporation of the solvent, and α-HNIW may be obtained as a by-product. When the amount of the solvent exceeds 50 ml, a long time is required until precipitation. When a mixed solvent of a good solvent and a poor solvent having a low boiling point is used as the solvent, the volume of the poor solvent is usually expressed as a volume ratio when the volume of the good solvent is set to 1 and usually 1 to 1
It is used in the range of 0, preferably 2 to 5. When it is less than 1, it is difficult to control the evaporation rate, and when it is more than 10, the amount of precipitated crystals is small.

As another method, there is a method in which methanol is used as a solvent without using a combination of a good solvent having a low boiling point and a poor solvent. When methanol is used as the solvent, the amount of the solvent is usually 60 to 100 ml per 1 g of HNIW,
Preferably, it is used in the range of 60 to 80 ml. When the amount of the solvent is less than 60, it is difficult to dissolve HNIW,
When the amount of the solvent exceeds 100, a long time is required until precipitation.

The evaporation rate of a mixed solvent of a good solvent and a poor solvent having a low boiling point is controlled in the range of usually 0.1 to 4.0% by weight / hour, preferably 0.5 to 3.0% by weight / hour. You. If the amount is less than 0.1% by weight / hour, a long time is required until precipitation, and if it exceeds 4.0% by weight / hour, α-HNIW or β-HNIW may be obtained as a by-product. The evaporation rate when methanol is used as the solvent is controlled in the range of usually 0.1 to 10.0% by weight / hour, preferably 2.0 to 7.0% by weight / hour. If the amount is less than 0.1% by weight / hour, a long time is required until precipitation, and if it exceeds 10.0% by weight / hour,
Α-HNIW or β-HNIW may be obtained as a by-product.

Although the evaporation rate of the solvent may be controlled by any method, the surface area of the upper portion of the container through which the evaporated solvent passes may be changed or the upper portion of the container may be filtered depending on the type of the good solvent having a low boiling point. Controlled by covering with. When a mixed solvent of a good solvent and a poor solvent is used, filtration is performed when the amount of solvent reduction reaches 20 to 30%. When methanol is used, filtration is performed when the amount of solvent reduction reaches 80 to 90%. Perform filtration. Regardless of which solvent is used, evaporation of the solvent is preferably performed with stirring to keep the concentration of HNIW in the solution uniform. Usually 50-500 rpm, preferably 100-3
It is performed in the range of 00 rpm. When using any solvent, the temperature during evaporation of the solvent is usually 0 to 50 ° C,
Preferably, it is carried out at 10 to 40 ° C.

[0019]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Hereinafter, hexanitrohexaazaisosoultitanium is referred to as “HNIW”. (Example 1) [α-HNIW → substantially ε-HNIW; example of using mixed solvent of acetone and xylene] 2.50 g of α-HNIW and 10 ml of acetone were added to a 200 ml beaker and completely dissolved, and then xylene was dissolved. Add 50 ml. The top of the beaker is covered with aluminum foil so that the surface area becomes 1/25, and stirring is performed at 200 rpm using a three-one motor while controlling the evaporation rate to be in the range of 1.0 to 1.5% by weight / hour. 2 at 20 ° C
After 0 hour, the precipitated crystals are filtered and dried, and substantially ε
2.31 g (92.4% yield) of -HNIW was obtained.

The structural analysis of the precipitated crystals was performed as follows. As a result of measuring an infrared absorption (hereinafter, referred to as “IR”) spectrum by a KBr method at a resolution of 2 cm ⁻¹ , α
Absorption of 1166 cm ^-1 which is characteristic absorption of HNIW, 9
Absorption of 03cm ^-1 is erased, 1138cm ^-1 which is the characteristic absorption of an ^{ε-HNIW, 1183cm -1, 1193cm} -1
Was confirmed. 739 cm ^-1 , 746 cm ^-1 , 7
52cm ^-1, 759cm ^-1, 4 pieces of absorption having a peak top of, 821cm ^-1, 2 pieces of absorption having a peak top of 833cm ^-1 was also confirmed. These absorption properties are described in the literature [Propellants, Explosives,
Pyrotechnics 19, 63-69 (199
4)], which is consistent with the characteristic absorption of the IR spectrum of ε-HNIW. From the above, substantially ε-HNI
It was confirmed that it was converted to W.

(Example 2) [β-HNIW → substantially ε-HNIW; Example using mixed solvent of acetone and xylene] In a 200 ml beaker, 2.50 g of β-HNIW and 10 ml of acetone were added and completely dissolved. , 50 ml of xylene are added.
The top of the beaker is covered with aluminum foil so that the surface area becomes 1/25, and stirring is performed at 200 rpm using a three-one motor while controlling the evaporation rate to be within 1.0 to 1.5% by weight / hour. After elapse of 20 hours at 20 ° C., the precipitated crystals were filtered and dried, and substantially ε-HN
2.35 g (94.0% yield) of IW was obtained. The structural analysis of the precipitated crystal was performed as follows.

The IR spectrum is obtained by the KBr method at a resolution of 2c.
As a result of measurement at m ⁻¹ , the characteristic absorption of β-HNIW, 1
The absorption at 154 m ^{-1 and} the absorption at 991 cm ^-1 disappear, and ε-
1138cm ^-1 , 1193c which is characteristic absorption of HNIW
m ^-1 , absorption was confirmed. Also, 739 cm ^-1 , 746
^{cm -1, 752cm -1, 759cm -1} , 4 pieces of absorption having a peak top of, 821cm ^-1, 2 pieces of absorption having a peak top of 833cm ^-1 was also confirmed. These absorption properties are described in the literature [Propellants, Explos].
ives, Pyrotechnics 19, 63-6
9 (1994)], which is consistent with the characteristic absorption of the IR spectrum of ε-HNIW. From the above, it was confirmed that it was substantially converted to ε-HNIW.

(Comparative Example 1) [α-HNIW → substantially ε-HNIW; example using mixed solvent of acetone and xylene] In a 200 ml beaker, 2.50 g of α-HNIW and 10 ml of acetone were added and completely dissolved. , 50 ml of toluene are added.
The mixture is stirred at 200 rpm using a three-one motor while distilling off the solvent at an evaporation rate of 5 to 7% by weight / hour. 2
After 5 hours at 0 ° C., the precipitated crystals were filtered and dried, but were not substantially converted to ε-HNIW.
2.48 g (99.2% yield) were recovered.

(Example 3) [α-HNIW → substantially ε-HNIW; Example using mixed solvent of ethyl acetate and toluene] 2.50 g of α-HNIW and 10 ml of ethyl acetate were added to a 200 ml beaker and completely dissolved. After that, 50 ml of toluene are added. The top of the beaker is covered with aluminum foil so that the surface area becomes 1/25, and stirring is performed at 200 rpm using a three-one motor while controlling the evaporation rate to be 1.0 to 2.0% by weight / hour. After 20 hours at 20 ° C., the precipitated crystals were filtered and dried, and 2.41 g of ε-HNIW substantially converted to ε-isomer (96.4% yield).
I got The precipitated crystal was substantially ε as in Example 1.
-HNIW was confirmed.

(Comparative Example 2) [α-HNIW → substantially ε-HNIW; Example using mixed solvent of ethyl acetate and toluene] In a 200 ml beaker, 2.50 g of α-HNIW and 10 ml of ethyl acetate were added and completely dissolved. After that, 50 ml of toluene are added. While the solvent is being evaporated at an evaporation rate of 5.0 to 7.0% by weight / hour, the mixture is stirred at 200 rpm using a three-one motor. After 5 hours at 20 ° C., the precipitated crystals were filtered and dried, but were not substantially converted to ε-HNIW.
2.49 g of HNIW (99.6% yield) was recovered.

Example 4 [α-HNIW → substantially ε-HNIW; Example using a mixed solvent of tetrahydrofuran and toluene] 200 ml
2.50 g of α-HNIW and 10 ml of tetrahydrofuran were added to a beaker and completely dissolved.
Add 0 ml. The solvent was distilled off at an evaporation rate of 1.0 to 2.0% by weight / hour, and 200 r by three one motor.
Stir at pm. After 20 hours at 20 ° C., the precipitated crystals were filtered and dried to obtain 2.31 g (yield 92.4%) of substantially ε-HNIW. The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

(Comparative Example 3) [α-HNIW → substantially ε-HNIW; Example using a mixed solvent of tetrahydrofuran and toluene] 200 ml
2.50 g of α-HNIW and 10 ml of tetrahydrofuran were added to a beaker and completely dissolved.
Add 0 ml. The liquid temperature is raised to 40 ° C., and the mixture is stirred at 200 rpm using a three-one motor while evaporating the solvent at an evaporation rate of 4.5 to 5.0% by weight / hour. 5
After the elapse of time, the precipitated crystals were filtered and dried, but were not substantially converted to ε-HNIW, and 2.48 g of α-HNIW.
(99.2% yield).

(Example 5) [α-HNIW → substantially ε-HNIW; an example using methanol as a solvent]
Add 1.0 g of NIW and 60 ml of methanol to completely dissolve. While the solvent is being distilled off at an evaporation rate of 5.0 to 6.0% by weight / hour, 200 rpm by a three-one motor.
Stir at m. After 20 hours at 20 ° C., the precipitated crystals were filtered and dried to obtain 0.95 g (yield: 95%) of substantially ε-HNIW. The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

(Example 6) [α-HNIW → substantially ε-HNIW; Example using a mixed solvent of methyl ethyl ketone and toluene] 200 ml
2.50 g of α-HNIW and 10 ml of methyl ethyl ketone were added to a beaker and completely dissolved.
Add 0 ml. The solvent was distilled off at an evaporation rate of 1.0 to 2.0% by weight / hour, and 200 r by three one motor.
Stir at pm. After 20 hours at room temperature, the precipitated crystals were filtered and dried to obtain 2.30 g (yield: 92.0%) of substantially ε-HNIW. The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

(Comparative Example 4) [α-HNIW → substantially ε-HNIW; Example using mixed solvent of acetone and heptane] 2.50 g of α-HNIW and 20 ml of acetone were added to a 200 ml beaker and completely dissolved. , 50 ml of heptane were added.
While the solvent is evaporated at an evaporation rate of 0.5 to 1.0% by weight / hour, the mixture is stirred at 200 rpm using a three-one motor. After 20 hours at 20 ° C., the precipitated crystals were filtered,
Dried but not substantially converted to ε-HNIW, α-HNIW
0.32 g (12.8% yield) of NIW was recovered.

(Comparative Example 5) [α-HNIW → substantially ε-HNIW; Example using mixed solvent of acetophenone and xylene] In a 200 ml beaker, 2.50 g of α-HNIW and 50 ml of xylene
And then 5 ml of acetophenone are added. 20
After 24 hours at ℃, the precipitated crystals were filtered, dried and substantially converted 1.98 g of converted ε-HNIW (yield 79.2).
%). The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

[0032]

According to the present invention, a high-density and high-energy ε-hexanitrohexaazaisowurtzitane crystal is
% And a good yield was obtained with a purity of not less than%.

Claims (9)

[Claims] 1. A method of dissolving hexanitrohexaazaisowurtzitanium represented by the following general formula (1) in a solvent to form a hexanitrohexaazaisowurtzitanium solution, and then evaporating the solvent to precipitate crystals. By using a mixed solvent of a good solvent and a poor solvent having a low boiling point as the solvent, the method for producing ε-hexanitrohexaazaisowurtzitane . W (NO ₂ ) ₆ (1) [wherein, W represents a hexavalent hexaazaisowurtzitanium residue represented by the following formula (2). ] 2. A solution of hexanitrohexaazaisowurtzitanium in a solvent to form a hexanitrohexaazaisowurtzitanium solution, and then evaporating the solvent to precipitate crystals, thereby obtaining ε-hexanitrohexaazaisowurtzitanium. A method for producing ε-hexanitrohexaazaisowurtzitane, wherein methanol is used as the solvent. 3. The method according to claim 1, wherein the hexanitrohexaazaisosoultitanium to be dissolved in the solvent is mainly composed of α-hexanitrohexaazaisosoultitanium, β-hexanitrohexaazisoulitoltitanium, or γ-hexanitrohexaazaisosoultitanium. The method for producing ε-hexanitrohexaazaisowurtzitane according to claim 1 or 2, wherein 4. The volume ratio of a good solvent and a poor solvent having a low boiling point is 1:
2. The method according to claim 1, wherein the range is from 1 to 1:10.
Or a method for producing ε-hexanitrohexaazaisowurtzitane according to 3 above. 5. The method according to claim 4, wherein the good solvent having a low boiling point is at least one of acetone, methyl ethyl ketone and tetrahydrofuran. 6. The method for producing ε-hexanitrohexaazaisowurtzitanium according to claim 4, wherein the poor solvent is toluene and / or xylene. 7. The process for producing ε-hexanitrohexaazaisowurtzitane according to claim 4, wherein the poor solvent is toluene. 8. Evaporation rate of the solvent is 0.1 to 4.0% by weight /
8. The method for producing .epsilon.-hexanitrohexaazaisowurtzitane according to claim 1, wherein the evaporation is performed within a time range. 9. The solvent is evaporated at a rate of 0.1 to 10.0% by weight.
3. The method for producing .epsilon.-hexanitrohexaazaisowurtzitane according to claim 2, wherein the evaporation is performed within a range of / hour.