JPS5973488A - Caking agent for solid propellant - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION More specifically, a water-tipped polybutadiene (HTPB) based caking characterized in that it contains a specific chain extender to improve the physical properties of the composite propellant. It's about cutting.

Composite propellants are composed of saponification and binding agents as their main components, with combustion improvers made of metal powder added as necessary, and their combustion characteristics and substance-like characteristics improve the performance of rockets. Widely used as a propellant for motors.

Typical examples of composite propellants include castable propellants such as ammonium perchlorate as a saponification agent, aluminum powder as a combustion improver, and a binder with polybutadiene as a handle material.

Conventionally, polybutadiene-acrylic acid copolymer (PBAA), polybutadiene-acrylic acid copolymer (PBAA), polybutadiene-acrylic acid copolymer (PBAA), etc.
Acrylic/L [monoacrylonitrile terpolymer (PBA)
N ) and terminal carboxyl group polybutadiene (GTP
B) '5σ] prepolymers have been used.

Among these, the composite propellant using 0TPB as a wiping material and binder 1 has the best ease of manufacture and physical properties,
Because it also has relatively high combustion performance, it has been used in high-performance rocket motors.

However, when trying to further improve the combustion performance of this propellant, especially the specific impulse, in the case of polybutadiene propellant, the solid content such as oxidizing agent is 88 to 90% by weight, that is, the binder is 12 to 10% by weight. The solids content must be increased because it theoretically shows the highest specific impulse when the composition is 1%. If the solid content is 88% or more, it is originally OTP B.
Because the viscosity of the prepolymer itself is relatively high, the viscosity of the propellant slurry at the time of manufacture becomes extremely high and fluidity is lost, making it difficult to manufacture.

In addition, the curing agent used in binders is mainly Tris (
1-(2-Methyl/I/)aziridinyl]phosphine oxide (MAPO), but this hardening agent is easily hydrolyzed by the moisture contained in the propellant, so this propellant deteriorates over time. It is easy to change and has problems with aging characteristics. especially? This tendency was remarkable in riJ Katashita.

Therefore, in order to solve the above-mentioned problem, HTP is used as a binder.
A propellant using B as a binder (H1'P B propellant) was developed.

This one? Since the HTPs prepolymer has good manufacturing properties due to its low viscosity properties, it is easy to reduce the amount of binder to 10 to 12% by weight, making it possible to improve the specific impulse. did.

In addition, a diisocyanate compound is used as a hardening agent in this propellant, and this diisocyanate compound
PB prepolymer reacts with water to form a strong and stable product.
Because it is crosslinked by forming so-called urethane bonds, this propellant has excellent heat aging resistance and stability over time.

Due to these advantages, HTPB-propelled mulberry is becoming the mainstream of composite propellants as a high-performance propellant to replace conventional propellants such as CTPB-propelled mulberry.

Typical HTP B prepolymers used for HTPB propulsion i propulsion 4C are Polybd R-45M and PolybdR-, which are manufactured by Alco Chemical Co., Ltd. in the United States.
There is 45HT.

R-45M is mainly used as a propellant, and the technology for its use has been established, but because it is a special product for propellants, there are few hedges and it is expected that it will be difficult to obtain in the future. Ru. On the other hand, R-45HT is a general-purpose product that is produced in large quantities, so there are no problems with availability and it is inexpensive, but when used as a propellant, the physical properties of the propellant are significantly inferior to R-45M. In particular, it was considered to be impractical due to its small depth.

Therefore, there was a desire to improve the physical properties of a propellant using R-45HT, which is the best in terms of manpower and cost.

In HT P B N' and Shinjo, the adhesion between the binder made of HTPB prepolymer and diisocyanate compound and oxidizing agent particles such as ammonium perchlorate is strong, so it imparts that adhesion. A binder is required as an additive. That is, like a propellant, the powder force is
In a composite material that is dispersed in a binder at a fI rate, the adhesion between the filler and the matrix binder is tυ
Because it affects the overall physical properties of the composite material, HTPB
In propellants, the selection of binders is an important means of improving physical properties.

From this point of view, a binder using R-45HT has been proposed in JP-A-54-84016. This binder uses an amine polyester in addition to a conventionally known aziridine polyester as a binder.

However, even with this binder, the tensile properties, especially the groaning, are about 20 to 30% lower than the binder with the optimal composition using R-45M, and the aging properties are also poor. It was still insufficient as a substitute propellant for the propellant used.

Here, when comparing R-5HT prepolymer and R-45M prepolymer, the average water #M number is R-415.
, HT is larger than R-45M by o, o s millimeter M/9. Hydroxic acid handle This mouse thickens water here ct 1
Since it is expressed as the reciprocal of the valence, I1 [( is R-4
5HT is smaller. Next, the average number of functional rice grains that absorb hydroxyl, which is calculated by the ratio of the average molecular weight and the 1 ji of hydroxyl, is compared.R-45HT has 2.32r and R-45M has 2.10. Therefore, it is determined that if R-45HT is cured with the same composition as R-45M, the average molecular weight between crosslinking points will be reduced, and as a result, the radius will be reduced.

The present inventors focused on this point, and as a result of repeated grinding on various types of 1-chain additives in order to increase the molecular weight between cross-linking points, by adding a specific chain additive, R-45HT The present invention was completed based on the knowledge that the physical properties of a propellant using a caking side using a prepolymer as a trapping material can be improved without impairing other properties.

That is, the present invention provides (a) a number average molecular weight of 22oO to 34;
00, and the hydroxyl value is now 0.78 to 0.98 mm.
Its micro-centering is 1.4 cis 15-y 25%) 1.4
Trance 55-65%, 1.2 biyu tv 15-25
%, (b) a diisocyanate curing agent, and (C) one or more binders selected from the group consisting of aziridine compounds, amine compounds, and hydantoin compounds. In caking for solid M Shinsou, (d) number average molecular weight is 1
200 to 3,500, and is characterized by containing a polybutadiene hydrogenated hydroxyl-terminated polybutadiene hydrogenated product with hydrogenated vinyl bond portions (80% or more) as a chain extension drop. Caking cutting for promotion town.

The hydroxyl-terminated polybutadiene prebolimer (a) used in the present invention is a polybutadiene prebolimer having hydroxyl residues at both ends. Product name: POlybd R-45
HT etc.

The usage of this prepolymer is usually about 4
The content is 5 to 90% by weight, preferably 60 to 80% by weight, Fjt%.

As the diisocyanate curing agent (b) used in the present invention, for example, isophorone diisocyanate (I
PDI), hexamethylene diisocyanate (HMDI)
) and dimeryl diisocyanate (DDI), etc.
Preferably it is IPDI.

The blending amount of the diisocyanate curing agent is NcoloH, if the JIt ratio of incyanate Kusunoki/Hyakushuhiro is expressed as NcoloH.
Co10H= ranges from 0.6 to 1.0, preferably from 0.75 to 0.96.

The aziridine compound used as the binder (0) in the present invention is, for example, MAPO, bisiso7talloyl-1-s (2-methyl)aziridine (HX-752
), tris(1-(2ethyl)aziridinyl)benzene (HX-s 68 ), 2 moles of MAPO and 0 adipic acid
．． Reaction product of 7 mol and 0.8 mol of tartaric acid (IT-4
) etc., preferably a mixture of HX-752 and MT-4, the mixing ratio of which is in the range of 1/2 to 2/1. In addition, examples of amine compounds include triethanolamine, N-methyldiethanolamine, cepatic acid (
7) Reaction product (N-8), reaction product of tetraethylenepentamine, acrylonitrile, and glycidol (
HX, -878) and the reaction product of tetraethylenepentamine and acrylonitrile (Hx-s7o), etc.
Preferably it is HX-878. Furthermore, examples of the hydantoin compound include di(2-hydroxyethyl)dimethylhydantoin (DHH) and di(2,-carboxylethyl)dimethylhydantoin, with DHE being preferred.

These binders are used in the form of citron or a mixture of two or more, and the amount thereof is 0.5 to 5 parts by weight of the viscosity. In particular, in the case of mixtures, 0.8 to 5 weight h of the total amount of caking
The χ part is preferred.

The specific milling process (d) used in the present invention has a number average molecular weight of 1,200 to 350o, and has a terminal hydroxyl process in which the vinyl bond portion (80% or more) is hydrogenated. It is a polybutadiene hydrogenated product and has hydroxyl groups at both ends.

If the number average molecular weight ht is less than 1200, the reaction rate with the diisocyanate curing agent is too fast, which shortens the pot life at the time of propulsion 11i[i], which is undesirable.If the number average molecular weight exceeds 8500, the viscosity increases. HTP
B Yarn caking Cutting Yarn caking The low viscosity property, which is a sign of caking, is lost, and the reaction rate with the diisocyanate curing agent becomes slow, so curing does not complete within the specified curing time, and physical properties change due to post-curing. Undesirable.

In addition, those whose vinyl bonds are not hydrogenated,
The vinyl bond due to its molecular structure is susceptible to oxidation, which leads to poor stability over time, which is undesirable.

The above-mentioned suitable chain cutting tool is, for example, Nl5SO-PBGI-1000, a trade name of Nippon Sodasha Geki.
, GI-2000, GI-8000, etc. Among them, GI-1000 is particularly preferable because it has the lowest viscosity and is comparable to the viscosity of the terminal water-treated polybutadiene prebolymer.

The compounding agent of these spreading agents is preferably 5 to 80 weight %, more preferably 10 to 25 weight % of the total weight of the hydroxyl-terminated polybutadiene prebolimer. 5 layers 1i
If the amount is less than 30%, the effect of kuminobu konshu will be small, and if the
If it exceeds 100%, the physical properties of the propulsion μs, especially the tensile strength and elastic modulus, will deteriorate, which is not preferable.

In addition to the above-mentioned components, a plasticizer may be added, if desired, for the purpose of, for example, improving the low-temperature physical properties of the propellant and reducing the viscosity of the binder. For example, dioctyl adipate (DOA), dioctyl sebaque) (
DO8), diisodecyl adipate (DIDA), and indecyl perabonate (IDP).

In addition, anti-aging agents, such as 2,
2'-methylene-bis(4methyl-〇-tert-butylphenol) (trade name A 0-2246) and the reaction product of diphenylamine and a7tone (trade name BLE
-25) etc. can also be added.

In order to manufacture Funposite propellant using the pre-caking mixture consisting of the above components, an oxidizing agent is added, and a combustion improver and a combustion catalyst are added to adjust the performance according to the package. Ru. As the oxidizing agent, ammonium perchlorate i, P
), cyclotetramethylenetetranitramine (' HM
X ) and cyclotrimethylenetrinitramine (RD
X) 9 is used, powder of aluminum, boron, etc. is used as a combustion improver, and iron ferrite (Fe, o) is used as a combustion catalyst.
8) or a 7-engine rosene dielectric material, etc. are used.

A composite propellant can be obtained using the above-mentioned components by a conventional oily method at ℃.

The propellant thus obtained using the viscous cutting of the present invention can be obtained by using the conventionally known caking (using both aziridine polyester and amine polyester as binders and without using a chain extender). Compared to propellants, their physical properties are significantly improved, e.g., the shear is significantly greater at the same tensile strength.

Moreover, the present invention has the advantage that many binders can be selected. In other words, the aging characteristics of HTPB propellants are greatly affected by the type of binder used. Conventionally, using a binder that is highly effective in improving physical properties results in poor aging characteristics; Binders with ambiguous properties are less effective in improving physical properties, and it has been difficult to select a binder that satisfies both. Since the physical toughness is improved, there is freedom in selecting the binder, and by selecting a binder with aging characteristics, it is possible to improve both the physical properties t+ and the aging characteristics. Another advantage of the present invention is that the hydroxyl-terminated polybutadiene prepolymer used (e.g., R-&5HT prepolymer) is a general-purpose product, so that fluctuations in loft, especially water The acid scavenging value fluctuates widely, which has a large effect on the physical properties of the propellant, but in the present invention, the f5
By adjusting the loading W, it becomes possible to suppress the fluctuation, and a propellant having stable physical properties can be obtained.

Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples.

Example 1 Using the caking compound of Example 1 shown in Table 1, the propellant shown in Table 1 was prepared as follows to obtain 17iWL.

First, 100 parts by weight of hydroxyl-terminated polybutadiene (trade name: Poly bd R-45HT, manufactured by Alco Chemical Co., Ltd.) pre-5 polymer was added with 2,z'-methylene-bis(4-methyl-6-tadiene), which is an antiaging agent. Added 1 part of Yabutil Fetoolun (trade name, AO-2,246),
Vacuum mixing was carried out for 80 minutes at 70″C.

Next, after bringing to normal pressure and room temperature, the terminal 1.゛water m 41 + ” addition polybutadiene hydrogenated product (manufactured by Nippon Soda Co., Ltd., trade name, Nl5S'O-PBGI) was prepared by sharp cutting.
-1000, number average molecular b11400), dioctylazibe) (DOA) as a plasticizer, 02 mol of MAP as a binder, 0.7 mol of adipinha, and 0.7 mol of tartaric acid. ,! 1 mole of the reaction product (IT-4) and bisiso7lyoyl-1-(2methyl)acyldi> (HX
-752) mixture (vehicle loss ratio MT -4/HX-7
5i'a40/[30) and mixed until uniform.

Next, the curing agent isophorone diisocyanate (IP)
DI) and after mixing, aluminum powder (average particle size 8μ
) and mixed thoroughly until it became a paste. Next, add ammonium perchlorate, which is a rlq chemical,
The mixture was heated to 60°C and mixed in a vacuum for 80 minutes, and the slurry-like mixture was cast into a predetermined mold under vacuum. After defoaming, it was cured at 60°C for 7 days to release the propellant. Obtained. The viscosity (slurry viscosity) of the mixture immediately after vacuum mixing was measured using an E-type viscometer. The results are shown in Table 1.

In addition, the tensile properties, aging properties, and combustion properties were measured using the propellant described below, and the obtained results were used in the
Shown in the table.

[Tensile properties]

A tensile test piece specified by the Propellant Properties Committee was prepared from the above propellant, and a tensile test was conducted using it at a tensile rate of 50/min and a test temperature of 20°C. The strain (Okihi) and elastic modulus were determined.

[Aging characteristics]

The cured propellant block was placed in a constant temperature bath at 60° C. for 45 days, after which it was subjected to the same tensile properties tests as described above.

[Combustion characteristics]

A combustion test was conducted using a small motor with an outer diameter of 80 mm using a normal combustion test method, and the combustion pressure was 60 kg・f/Cm.
The burning speed and specific impulse of No. 2 were determined.

Examples 2 to 14 Each of the propellants shown in Table 1 with the binder composition of Examples 2 to 1 shown in Table 1 was subjected to iUM& in the same manner as in Example 1.

The viscosity of each mixture after vacuum mixing was measured according to Example 1, and the results are shown in Table 1.

In addition, each test according to Example 1 was conducted using each of the obtained propellants, and the results are shown in Table 1.

Comparative Example 1-4 As shown in Table 2, @Extensioner was not included.
Example 1 of each propellant with the compounding composition of Comparative Examples 1 to 4 in the table.
It was polarized using a method similar to .

The viscosity, drag characteristics, aging characteristics, and combustion characteristics of the slurry were measured in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Examples 5 to 7 1 Including elongation cutting, each of the 11 extensions was carried out using the formulations of Comparative Examples 6 to 7 in Table 2, in which R-15M was used instead of R-45HT as the terminal hydroxyl group polybutadiene prebolimmer. It was packed in a manner similar to Example 1.

The viscosity, tensile properties, aging properties, and combustion properties of the slurry were measured in the same manner as in Example 1, and the results are shown in Table 2.

(Note) In Table 1, R-45HT prepolymer: Hydroxyl-terminated polybutadiene IPDI manufactured by Alco Chemical Co., Ltd.: Isophorone diisocyanate MT-4:
MAP02 moles and adipi>(lj, 0,7 moles/l
Reaction product of / and 0.8 mol of tartaric acid (synthesized and used) 1 (X-752: Bisiso7taloyl-1-(2methyl)aziridine (manufactured by 3M) HX-878: Tetraethylenepentamine and acrylonitrile and glycidol (produced by 3M Co., Ltd.) DHE: Di(2-and-droxyethyl)dimethylhydantoin (synthesized and used) N-I Reaction product of N-methyljetanolamine and cepatic acid (synthesized and used) GIloo (1: terminal hydroxyl tachibana), 2-added polybutadiene hydrogenated compound with an average molecular weight of several thousand 1 and an average molecular weight of 1+oo (manufactured by Nippon Soda Co., Ltd.); (manufactured by Nippon Soda Co., Ltd.) G-8000j Same as above, except that the number average molecular weight is 13100 (manufactured by Nippon Soda Co., Ltd.) DOA: Dioctyl adipate or higher Comparing actual examples 1 to 10 and 18 to 14 with comparative examples 1 to 4 As is clear, the propellant using the binder of the present invention has excellent physical properties, in particular the strain at maximum stress (Io% or more in absolute value,
As a result, it is clear that the propellant using the binder of the present invention has improved by more than 8"1jIJ. As is clear from the comparison with Examples 1, 11 and 12 and Comparative Examples 5 to 7, the propellant using the binder of the present invention ,R
-85M Breho.

It was confirmed that the propellant possesses physical properties equivalent to propellants using reamers and is sufficiently usable for practical use.

Patent applicant: NOF Corporation

Claims (1)

[Scope of Claims] 1(a) A number average molecular weight of 2,200 to 8,400, a hydroxyl value of 0.73 to 0.98 meq/9, a sonomicrostructure of 1,4 cis 15 to 25%, 1. 4 transformer 55~
65%, hydroxyl-terminated polybutadiene prebolimer having 15 to 25% of 1,2 vinyl, and IMi or two or more selected from the group consisting of Φ) diisocyanate curing agent, (C) aziridine compound, amine compound, and hydantoin compound. (d) A hydrogenated polybutadiene having a number average molecular weight of 1,200 to 8,500 and having 1,2 terminal hydroxyl groups and hydrogenated at the vinyl bond as a chain extender; A solid propellant binder characterized by containing: The solid propellant caking according to claim 1, wherein the amount of the chain extender is 6 to 3% by weight of the total amount of the hydroxyl-terminated polybutadiene prebolimer and the chain extender. agent 0