JP3177698B2 - High energy polyether derivatives - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel polyether derivative which can be used as a binder for a propellant, and a propellant composition using the derivative.

[0002]

BACKGROUND OF THE INVENTION In general, solid propellants are roughly classified into heterogeneous explosives, which are a mixture of an oxidizing agent and a hydrocarbon polymer, and homogeneous explosives, which are formed by mixing and forming nitroglycerin and nitrocellulose as main components. Is done. The former explosive, which uses ammonium perchlorate or aluminum powder, is smoke-producing but has high specific impulse and excellent mechanical properties. On the other hand, when the latter homogeneous explosive is used as a propellant, the specific thrust is low, but the propellant is smokeless.

In recent years, studies have been conducted on the application of a polyether having an azide group in a side chain of a prepolymer as a main component of a binder, for the purpose of improving the combustion performance of these propellants, in particular, making smokeless and high energy. ing. For example,
A polyether having an azide group represented by the following general formula IV in a side chain (US Pat. No. 4,268,450) and a polyether having an azide group and a nitrate group represented by the following formula V in a side chain (US Pat. No. 5,099,042) No.) has been proposed.

[0004]

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[0005] These azide group-containing polyethers are
Due to high heat of formation and high density, when used for propellants, propellants with higher energy than propellants using common binders are obtained. In addition, azide group-containing polyethers are expected to be future binders because they become high-energy and smokeless propellants by using ammonium nitrate or nitramine compounds as oxidizing agents.

However, when these azide group-containing polyethers are used as a binder for a propellant, they have extremely excellent combustion characteristics, but their mechanical properties at low temperatures are remarkably reduced. Because of the fatal deficiency of this, they are generally improved by copolymerization with tetrahydrofuran (U.S. Pat.
No. 806,613), it is necessary to add not less than 30% of tetrahydrofuran, and there is a problem that the content of azide group is relatively reduced and energy cannot be increased.

[0007]

Under these circumstances, the present invention makes the most of the combustion performance of an azide group-containing polymer and improves the low-temperature properties of a propellant using an azide group-containing polyether derivative. Accordingly, it is an object of the present invention to provide a novel azide group-containing polyether derivative and a propellant composition containing the same as a binder.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies in consideration of the above-mentioned problems of the prior art, and as a result, introduced a specific polyester as a soft segment into the main chain of an azide group-containing polyether. Polyether derivative
The present inventors have found that the present invention can be adapted to the purpose, and have made the present invention based on this finding.

That is, the present invention provides the following (1) to (4)
It is.

(1) Polyether derivative represented by the following general formula I

[0011]

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[Wherein, m + n is an integer of 5 to 30,
m or n may be 0. p + q is an integer of 1 to 10. p or q may be 0. These polyether units include the case of both random copolymerization and the case of block copolymerization. o is an integer of 3 to 30. R ¹ , R ² , and R ³ each represent the same or different, linear or branched alkylene group having 2 to 6 carbon atoms. (2) Polyester component II in polyether derivative represented by general formula I

[0013]

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The polyether derivative according to (1), wherein the ratio is 7 to 30% by weight.

(3) A propellant composition comprising a binder obtained by adding a polyisocyanate and a diisocyanate to the polyether derivative according to (1) or (2), and further including an oxidizing agent.

(4) A propellant composition further comprising a low melting point plasticizer added to the composition of (3).

Hereinafter, the polyether derivative represented by the general formula I in the present specification is referred to as BNPE.

(5) Polyester represented by the following general formula III

[0019]

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A process for producing the polyether derivative according to (1) by ring-opening polymerization of 3,3-bisazidomethyloxetane and 3-nitratomethyl-3-methyloxetane.

Wherein R ¹ , R ² and R ³ are the same or different and each represent a linear or branched alkylene group having 2 to 6 carbon atoms, and 0 is an integer of 3 to 30. The BNPE of the present invention comprises a 3,3-bisazidomethyloxetane polymer (referred to as P-BAMO) component and a 3-nitratomethyl-3-methyloxetane polymer (P-NM
MO) and a polyester component, and the ratio of the polyester component is preferably in the range of 7 to 30% by weight, more preferably 20% by weight or less. When the content is less than 7% by weight, the glass transition temperature of BNPE becomes high, and the low-temperature properties deteriorate. On the other hand, if it exceeds 30% by weight, the content of azide group is relatively reduced and the effect of increasing energy is lost.

The BNP of the present invention represented by the above general formula I
E contains a polyester residue serving as a soft segment represented by the general formula II. As the polyester III which is a starting material of the BNPE, various ordinary polyesters are used, and the production method is not limited. Among them, those having a hydroxyl group at the terminal are BNPE represented by the general formula I.
In the production of the oxetane derivative, the oxetane derivative is preferable because it has excellent reactivity as an initiator when the ring-opening polymerization is carried out, and generation of side reactions is suppressed.

The number of hydroxyl groups in one molecule is not strictly limited to 2, but one having a value of 1.5 or more and 4.0 or less is used. Among them, those having 2.0 or more and 4.0 or less are more preferable.

The repeating unit o of the polyester resin III is 3 to 30, and if o is lower than 3, the cured product becomes hard and the softness is lost. When o exceeds 30, the azide group content decreases.

The synthesis of polyester III, which is a starting material for polyester resin residue II, is carried out by, for example, heating and dehydrating a polycarboxylic acid or a polycarboxylic anhydride and a polyhydric alcohol under reduced pressure or normal pressure. It can be performed by a synthetic method. The reaction can be promoted by adding a catalyst to the reaction system. As the esterification reaction catalyst, any of known esterification catalysts can be used. If necessary, a suitable solvent can be used.

Examples of such polycarboxylic acids or polycarboxylic anhydrides include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, dodecanoic acid, dimer acid, tetrahydrophthalic acid and tetrahydrocarboxylic acid. For aliphatic or alicyclic saturated dibasic acids such as phthalic anhydride, hexahydrophthalic anhydride, endmethylenetetrahydrophthalic anhydride, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, halogenated phthalic anhydride, etc. There is a representative aromatic saturated dibasic acid or its anhydride, and an unsaturated dibasic acid represented by maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, chlormaleic acid, etc. is used. You can also. These can be used alone or in combination of two or more.

In the present invention, any of the above-mentioned polycarboxylic acids can be used. Among them, adipic acid is generally and preferably used.

Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, 1,2-butanediol, 1,3 Aliphatic glycols represented by -butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, dimer diol, and the like; -Alicyclic glycols represented by cyclohexanediol, hydrogenated bisphenol A, dimer diol, and the like can be used. These may be linear or branched. These polyhydric alcohols can be used alone or in combination.

The polyester component used as a soft segment in the BNPE of the present invention preferably has hydroxyl groups at both ends and has a glass transition temperature of -60 ° C or lower, more preferably -70 ° C or lower. R ¹ and R ³ in the general formulas I and II are preferably those having a methyl group, an ethyl group or the like in the side chain of pentene.

The BNPE of the present invention can be synthesized by subjecting an oxetane derivative to general cation polymerization or anion polymerization using the above polyester as a polymerization initiator.

For example, in the case of cationic polymerization, boron trifluoride diethyl ether is used as a polymerization initiator in dichloromethane.
Charge ter complex and polyester
Bisazidomethyloxetane (referred to as BAMO) and 3
-Nitratomethyl-3-methyloxetane (referred to as NMMO) is added dropwise, and the mixture is polymerized at 25 ° C to obtain BNPE of the general formula I.

BAMO and NMMO undergo ring-opening polymerization on both sides of a polyester represented by the general formula III as a block polymer or as a random polymer. In the block polymer part, P-BAMO and P-NMMO
Are not limited, and these P-BAMO and PN
The block polymer portion of the MMO may be repeated several times and may partially include a random polymer portion. Furthermore, BAMO and NMMO do not necessarily need to be polymerized on both sides of the polyester represented by the general formula III,
This includes the case where NMMO and BAMO are polymerized only on one side of the polyester, and the case where NMMO is polymerized on one side of the polyester and BAMO is polymerized on the other side. P-B
The repeating units m and n of AMO are preferably 5 to 30 in total, and the repeating units of P-NMMO are preferably 1 to 10 in total of p and q.

A propellant can be prepared by adding an oxidizing agent to a binder obtained by adding a polyisocyanate and a diisocyanate as a curing agent to the BNPE obtained in this manner.

The BNPE polymerized in the present invention is usually a diol, and needs to be crosslinked to impart rubber elasticity as a propellant. Generally, triols such as glycerin, trimethylolpropane and glycerin trisinolate are used as a crosslinking agent, and diisocyanates such as tolylene diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate are compounded as a curing agent to form a binder. However, from the point that the original purpose is to increase the energy by containing a large number of azide groups,
In this method, an isocyanate for reacting with the triol is required, so that the amount of a crosslinking agent or a curing agent containing no azide group increases.

Therefore, in the present invention, when triisocyanate and diisocyanate are used when BNPE is a diol, the content of azide group is increased as compared with the general composition, and the energy can be increased. Moreover,
It has been found that a binder or a propellant composition cross-linked and cured with triisocyanate and diisocyanate has a unique effect that the glass transition temperature (Tg) is greatly reduced as compared with a cross-linked cured product of triol and diisocyanate. It has been found that adding a low melting plasticizer increases its effect.

The triisocyanate used at this time is not particularly limited. For example, 1,3,5-tris (6
-Isocyanatohexyl) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione (hereinafter referred to as duranate), 1,3,5-cyclohexanetriisocyanate, triphenylmethanetriene And isocyanate. The diisocyanate to be used is not particularly limited, but typical examples include tolylene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate. As the oxidizing agent, those usually blended in a propellant are used, and examples thereof include ammonium perchlorate, ammonium nitrate, tetramethylenetetranitroamine (referred to as HMX), and trimethylenetrinitroamine (referred to as RDX). . These include metal powders such as aluminum, metal oxide powders, organic lead salts,
A known combustion catalyst such as lithium fluoride may be added. Further, a curing catalyst such as an amine, an organotin compound, or acetylacetone metal, or a known binder such as an aziridine compound can be added to the binder as needed.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described specifically with reference to examples.

Example 1 BNPE was produced by the following method.

As the polyester to be the soft segment of the BNPE of the present invention, 3-methylpentane-1,5-
30 g of esterified product of diol and adipic acid (number average molecular weight is 548, glass transition temperature is -78 ° C)
47 mol), and boron trifluoride diethyl ether
15.5 g (0.1092 mol) of ter complex 200 g of dichloromethane was charged into the flask and stirred. Next, while maintaining the temperature at 25 ° C., 196.4 g of 3,3-bisazidomethyloxetane serving as a polyether segment was obtained.
(1.169 mol) and 73.6 g (0.501 mol) of 3-nitratomethyl-3-methyloxetane mixed with 270 g of dichloromethane were added dropwise.
Stirring was performed for hours.

Thereafter, 200 g of a saturated saline solution was added under stirring to stop the reaction, and then an aqueous solution of sodium hydrogen carbonate was added to neutralize the reaction solution. Next, the dichloromethane layer in the reaction solution was separated by a separating funnel, the separated solution was washed with 1 liter of water, and volatile components were removed by a rotary evaporator to obtain a colorless transparent liquid. Was.

FIG. 1 shows the infrared absorption spectrum of the product, and FIG. 2 shows the description of each absorption peak in FIG. FIG. 3 shows the NMR spectrum of the product, and FIG. 4 shows the explanation of each peak in FIG.

As a result of analysis by an infrared absorption spectrum and a nuclear magnetic resonance apparatus, this liquid is a BNPE having a structure represented by the following general formula. On the average, m + n is 10.5,
p + q is 4.5, o is 2 and BAMO
And NMMO were randomly arranged.

[0043]

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The number of moles (o) of the polyester of this polymer and the number of moles of BAMO and NMMO (m + n + p +
It was found that the ratio (o) / (m + n + p + q) to q) can be controlled by adjusting the amount ratio of polyester, BAMO, and NMMO used in the polymerization.

Example 2 According to the method of Example 1, polyester, BAMO and N
MMO was polymerized at the ratios shown in Table 1 to obtain a polymer. Further, with respect to 100 parts of the obtained polymer, with the composition shown in Table 2,
Further, dibutyltin dilaurate 0.02 is used as a curing catalyst.
A binder was prepared by adding a portion, and the mixture was heated and cured into a plate having a thickness of 3 mm. Using this cured product, tan δ was determined by measuring the dynamic elastic modulus. Table 2 shows the results.

When BNPE having a polyester component of 7% or more was used, tan δ (generally said to be close to the glass transition point) was significantly reduced as compared with the comparative example, which proved to be effective. .

The polymer of the comparative example is a polymer synthesized by changing the polyester used as the polymerization initiator in Example 1 to 1.4-butanediol.

[0048]

[Table 1]

[0049]

[Table 2]

Example 3 A polyester and a boron difluoride diethyl ether complex were charged into a flask and stirred in the same manner as in Example 1.
Next, a 50% dichloromethane solution of 3-nitratomethyl-3-methyloxetane was added dropwise while maintaining the temperature at 25 ° C, and the mixture was stirred for 5 hours after the addition. Further, a 50% dichloromethane solution of 3,3 bisazidomethyloxetane was added dropwise, and the mixture was stirred for 5 hours after the addition, and then saturated saline was added to stop the reaction, and the reaction solution was purified.

As a result of analyzing the chain structure of the product thus obtained with a nuclear magnetic resonance apparatus, BAMO and NMMO were analyzed.
Were found to be arranged in blocks.

Example 4 A binder having the composition shown in Table 3 was prepared in the same manner as in Example 2 for the comparative example of Example 2 and 100 parts of BNPE of the present invention, and ammonium perchlorate was prepared in the following manner. A propellant having a composition of 77% and a binder of 23% was produced.

First, a binder component and ammonium perchlorate (AP) were charged and mixed under vacuum at 50 ° C. for 40 minutes, and then the mixture was poured into a casting container and cured at 60 ° C. for 5 days to prepare a propellant. Obtained.

With respect to the obtained propellant, a tensile test specimen specified in the propellant drug properties conference was prepared, a tensile test was performed, and the tensile strength and elongation at break of the propellant were determined. Table 4 shows the results.

[0055]

[Table 3]

[0056]

[Table 4]

[0057]

As described above, the BNPE of the present invention is a novel substance that has never been synthesized in the past, and can significantly improve the mechanical properties at a low temperature significantly as compared with conventionally known azide polymers.

In addition, since only about 10% of the polyester has sufficient effect in terms of energy, the azide group content is larger than that of the conventional product, and a high-energy, smokeless propellant must be prepared. Is now available.

[Brief description of the drawings]

FIG. 1 is an infrared absorption spectrum of BNPE of Example 1.

FIG. 2 is an explanatory diagram of the infrared spectrum of FIG. 1;

FIG. 3 is an NMR spectrum of BNPE of Example 1.

FIG. 4 is an explanatory diagram of the NMR spectrum of FIG. 3;

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08G 63/685 C08G 63/685 C08L 75/08 C08L 75/08 F42B 5/16 F42B 5/16 15/00 15/00 (72 ) Inventor Tadamasa Harada 2620 Ojiri, Oita City, Oita Prefecture Asahi Kasei Kogyo Co., Ltd. (56) References JP-A-5-51444 (JP, A) JP-A-6-24887 (JP, A) JP-A-5 -59166 (JP, A) JP-A-8-259366 (JP, A) JP-A-7-291177 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 65/26- 65/28 C06B 45/00-45/36 C06D 5/00-5/10 C08G 18/50 C08G 63/66-63/676 C08G 63/685 C08L 75/08 F42B 5/16 F42B 15/00-15 / 38 CA (STN)

Claims (5)

(57) [Claims] 1. A polyether derivative represented by the following general formula I: Embedded image [Wherein, m + n is an integer of 5 to 30, and m or n is 0.
May be. p + q is an integer of 1 to 10. p or q may be 0. These polyether units include the case of both random copolymerization and the case of block copolymerization. o is 3
Is an integer of up to 30. R ¹ , R ² , and R ³ each represent the same or different, linear or branched alkylene group having 2 to 6 carbon atoms. ] 2. A polyester component II in a polyether derivative represented by the general formula I. 2. The polyether derivative according to claim 1, wherein the ratio of the polyether derivative is 7 to 30% by weight. 3. A propellant composition comprising a binder obtained by adding a polyisocyanate and a diisocyanate to the polyether derivative according to claim 1 or 2, and further comprising an oxidizing agent. 4. A propellant composition comprising the composition of claim 3 and a low melting point plasticizer. 5. A polyester represented by the following general formula III: The method for producing a polyether derivative according to claim 1, wherein 3,3-bisazidomethyloxetane and 3-nitratomethyl-3-methyloxetane are subjected to ring-opening polymerization. [In the formula, R ¹ , R ² , and R ³ each represent the same or different and are a chain or branched alkylene group having 2 to 6 carbon atoms, and 0 is an integer of 3 to 30. ]