JPH0345585A - Double base-system propellant composition and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject composition having high specific impulse and combustion speed and excellent producibility containing aliphatic polyether having terminal hydroxyl group expressed by specific formula and isocyanate compound in raw material in a double base-system propellant having fixed component composition. CONSTITUTION:A double base(DB) propellant substantially composed of nitrocellulose(NC) and nitroglycerin(NG) or liquid nitroester as principal components is produced as follows. 3-20wt.% aliphatic polyether expressed by the formula having terminal hydroxyl group containing azide methyl group in side chain and isocyanate compound are further contained in said raw material. Then, said polyether is made to three-dimensionally crosslinked structure to afford the aimed DB-system propellant composition. Besides, said polyether is suitable as a binder of DB propellant having excellent miscibility with NG.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a cross-linked D B II propellant in which a binder is added to a double base (hereinafter abbreviated as DB) propellant, and a method for producing the propellant. Regarding.

In particular, the present invention relates to a propellant that improves the specific impulse and coarsens the combustion velocity to 6, and that also has excellent manufacturability, and a method for producing the propellant.

(Prior Art) DIJ propellants are mainly composed of nitrocellulose (hereinafter abbreviated as NC), nitroglycerin (hereinafter abbreviated as NG) or liquid nitroester, and also include an inert plasticizer, a stabilizer, a combustion catalyst, etc. Part 13: NG and plasticizer penetrate into the NC fibers, gelatinize, and solidify.
Most of the 1I-like properties are controlled by the physical properties of NC.

DI311 additive (Although it has the excellent characteristic of being smokeless when burned, its strength decreases at high temperatures, and if the strength at high temperatures is maintained, the elongation at low temperatures decreases, etc.) However, it has the disadvantage of being easily influenced by its Isoshiro-like nature.

In order to solve this problem, a so-called binder-crosslinked Dn ti propellant composite D D 11! is added to the D B II propellant as a binder. Advance drug propellants (CDB) and elastomer modified DB propellants (also called EMDB or EMCDT3>) have been developed.

The binder used in the binder rack 1n type D113 propellant is 2, for example, in Japanese Patent Publication No. 57-49518:
In the manufacturing process of double-base propellants containing polyurekne resins, prepolymers 2 to 15f for urethane elastomers containing tetramethylene groups are used to produce double-base propellants containing all of the prepolymers 2 to 15f and a catalyst added as necessary. ``Method'' is disclosed, and also published in Japanese Patent Publication No. 57-4951
Publication No. 9 states, ``In a double-base propellant containing nitrocellulose, nitroglycerin, or liquid nitroester as the main components, and adding an oxidizing agent and metal fuel as necessary, part or all of the plasticizer is added to the terminal. Number of functional groups is 1 to 3
A double-heath propellant composition characterized in that the total amount of a polyester or polyether main chain polyol having an average molecular weight in the range of 500 to 5000 and an incyanate compound is converted to 1 to zomm% by GL. ' has been disclosed.

<Problems to be Solved by the Invention> However, these binders have a small heat of formation, and are polyether or polyester compounds containing carbon atoms or hydrogen atoms as their main components, so when added to a propellant, the specific impulse is low. decline was inevitable.

The purpose of the present invention is to provide a binder-crosslinked DB propellant that has a high specific impulse and a high combustion rate by using a binder with a large energy content, and which has a poor productivity, and a method for producing the propellant. It is about providing.

Means for Solving the Problems The present invention provides a double base propellant containing nitrocellulose and nitroglycerin or liquid nitroester as the main components, which contains 3 to 1% of the general formula in the raw material, ) is characterized in that it contains a terminal hydroxyl group aliphatic polyether and an isocyanate compound having an azidomethyl group in the side chain, and a three-dimensional crosslinked product of the terminal hydroxyl group aliphatic polyether and the incyanate compound is present. In the method for producing a double-base propellant composition and a double-base propellant containing nitrocellulose and nitroglycerin or liquid nitroester as substantial main components, 3 to 20% by weight of the general formula ( In the formula, n represents 10 to 50.m+l represents 1 to 10.)
Production of a double-base propellant composition characterized in that a hydroxyl group aliphatic polyether having an azidomethyl group in the side chain and an isocyanate compound are present, and the polyether is three-dimensionally cross-linked. Regarding the method.

The DB-11im drug of the present invention is particularly suitable for injection-type or infant-type DBI! I'm using an i-adhesive drug. For this purpose, NC, which is the substantial main component, is preferably fine particles of plus decyl nitrocellulose (PNC) or ball powder (BP), or NC small granules molded by solvent extrusion.
In addition, known liquid nitroesters can be used.

Next, in the double-based tlI promoter composition of the present invention, 6.
These may include the following:

T! ! As the Avl catalyst, lead compounds such as salicylic acid 10 and stearin U tO, and copper compounds such as copper salicylate and copper stearate can be used. As the stabilizer, known stabilizers such as ethyl centralit (ECL) and 2-nitrodiphenylamine (2NDPA) can be used.

Commonly used inert plasticizers include diethyl chloride (DEP) and dioctyl phthalate (DOP).
), phthalate esters such as diocuburadibate (
DOA), adipic acid esters such as di-n-propyl adipate (DPA), phosphoric acid ester ER2, and the like can be used. Nutrient agents include inorganic oxidizing agents such as ammonium perchlorate (AP) and ammonium nitrate (AN), and cyclic nitramine compounds (RD).
Examples include nitro compounds such as 611 acid esters such as X, II M

Next, the polyether represented by the above formula, which is a feature of the present invention, will be explained. This polyether is characterized by having an azide group in its molecule. Because it has an azide group with large strain, the heat of formation of a single polyether becomes large, and because it contains many nitrogen atoms,
Since nitrogen gas is generated during combustion of the II fuel, the specific impulse increases by 1, and at the same time the combustion speed increases. In addition, this polyether has the characteristics of having good compatibility with NG, slowing down the sensitivity of NG, and increasing the gelation rate with NC, and is suitable for application to D B l[i drug delivery. It is convenient for That is, it has the characteristics that it is possible to work safely during pulling with a car that has a low NG sensitivity, and that the curing time can be shortened with a car that has a high gelation rate with NC.

In the polyether represented by the general formula used in the present invention, when the value of n exceeds 50, the viscosity becomes high and the productivity becomes poor.

On the other hand, if the value of n is less than 10, the molecular weight of the polyether becomes small and the crosslinking density becomes high, so that the elongation of the propellant at low temperatures becomes insufficient.

Moreover, since the number of azidomethyl groups decreases, it becomes impossible to obtain a large specific III force.If 1m+2 exceeds 1O, the number of inert parts increases and the energy decreases. Preferably m
+42 is within the range of nX0.2.

The content of wood polyether in the original vehicle 4 is 3 to 20Tnff
i%. Preferably it is 5-15I11%. If the content is less than 3%, the mechanical properties of the propellant will not be improved sufficiently, and if it exceeds 20%, lit i1! It is not practical because the specific impulse of the drug decreases.

The incyanate compound that reacts with the present polyether may be a generally known isocyanate compound, such as hexamethylene diisocyanate (IIDI), tolylene diisocyanate (TDI), diphenylmethane polyisocyanate (PPMPI), inborone diisocyanate (PPMPI), IPDI), etc.

In addition, since this polyether is trifunctional, in order to make the crosslinking into a three-dimensional structure, a trifunctional incyanate compound is used, or one, for example, trimethylolpropane (TM
P), polyether polyol, boester polyol, and other trifunctional or higher functional polyols can be used. Preferred is trimethylolpropane (TMP) or
Molecule jl It is a polyol having a trifunctional group of 1000 or less or a functional group of more than 1,000.

In addition, a reaction catalyst between an isocyanate compound and a hydroxyl group can be used to adjust the curing time9. Examples of the curing catalyst used in the present invention include dibutyltin dilaurate (DBTDL) and dibutyltin (2-ethylhexoate). These are organic tin compounds, organic bismuth compounds such as triphenylbismuth, and amines such as triethylenediamine.

Next, a method for producing the polyether represented by the above general formula will be exemplified.

A reaction catalyst is dissolved in diols consisting of ethylene glycol, propylene glycol, α-monochlorohydrin, and their polymers, and epichlorohydrin and ethylene oxide or propylene oxide are mixed together in the system. An addition reaction produces a hydroxyl-terminated aliphatic polyether with chloromethyl groups on side 1i, and then the polyether is reacted with sodium azide in dimethylformazide (DMF). The obtained polyether was analyzed by single element analysis, infrared spectroscopy, molecular measurement, and water U.
It was determined by convex measurement that the structure is expressed by the above general formula.

<Effect of the invention> The terminal hydroxyl group aliphatic polyether having an azidomethyl group in the side chain shown in the present invention has good compatibility with NG.
B 0 that can be applied as a propellant binder
The CDB propellant using this polyether as a binder is similar to the conventional CDB tl! It has excellent characteristics such as high specific impulse and high combustion rate, and the manufacturing method of the present invention is easy to manufacture.

<Examples> The present invention will be explained in more detail below using Examples and Comparative Examples. Note that all parts and percentages in each example are based on weight.

Example 1 NG in a vertical mixer equipped with a stirrer, heating device, and vacuum device
54 parts, 2 parts of 2-nitrodiphenylamine as a stabilizer, 8.48 parts of polyether represented by the above formula where n is 25, m = 1, e = 0, trimethylolpropane 0.3
2 parts, add 2.0 parts of lead salicylate, 40°C, 5 mm.
Mixing and dehydration was carried out for 1 hour in a vacuum of 11 g or less to obtain a uniform wave component. 34 parts of NC11 particles with an average diameter of 30 microns were added to this mixed solution, and premixed by hand stirring.
Premixing was carried out for 10 minutes under atmospheric pressure. Furthermore, 40
℃, 5 mm, 11 g or less of vacuum for 1 hour, and then hexamethylene diisocyanate 1.2
After premixing by hand stirring for 5 minutes,
Mixing was carried out for 30 minutes at 0° C. and a vacuum of less than 5 parts mHg. The filled propellant slurry was cast under a vacuum of 5 mm and 11 g or less into a cylindrical shape of 80 mm in diameter having a core of 40 mrm in diameter. In addition, it was cast into a block shape for mechanical property samples. A cylindrical propellant obtained by curing for 5 days in a constant temperature bath at 60°C was heated to 140ml.
It was cut to length and used as propellant for rocket motors. Using this rocket motor propellant, a combustion test was conducted at a pressure of aokg/c- to obtain specific impulse data. The aperture ratio of the nozzle used was 6, and the nozzle opening angle was 18 degrees. Table 1 shows the specific impulse measurement results. On the other hand, from block propellant to JA
Cut out a NNAF type tensile test sample, +50℃, -30
The test was conducted at each temperature of .degree. C. and a drawing speed of 501/min. Table 1 shows the measurement results of the specific impulse of the raw material composition and the tensile speed.

Example 2 A propellant was manufactured in the same manner as in Example 1 using the raw materials and blending composition shown in Example 2 in Table 1, and was subjected to combustion tests and tensile tests in the same manner.
A ceremony was conducted. The results are shown in Table 1.

Example 3 A propellant was produced in the same manner as in Example 1 using the raw materials and composition shown in Example 3 in Table 1, and a combustion test and a tensile test were conducted in the same manner. The results are shown in Table 1.

Example 4 All treatments were carried out in the same manner as in Example 1, except that 25 parts of RDX was added when performing mixing and dehydration at 40° C. at a vacuum of 5 mm and 11 g or less. Table 1 shows the raw material composition, specific impulse measurement results, and tensile speed.

Example 5 A vertical mixer similar to the one used in Example 1 was
G59 part, stabilizer 2-nitrodiphenylamine 2
part, n=25. 8.48 parts of polyether represented by the above formula where m=1 and n=o, 0.0 parts of trimethylolpropane.
Add 32 parts, 2.0 parts of lead salicylate, and 10 parts of aluminum, and heat at 40°C under a vacuum of 5au++lIg or less.
Time mixing and dehydration were performed to obtain 12 uniform liquid components. Add 29 NClej particles with an average particle size of 30 microns to this mixture.
The mixture was premixed by manual stirring for 5 minutes and then under atmospheric pressure for 10 minutes. Furthermore, 40℃, 5t+++l1g
Mixing was performed for 1 hour at the following vacuum level, then 1.2 parts of hexamethylene diisocyanate was added, premixed by hand stirring for 5 minutes, and then mixed for 30 minutes at 40°C and at a vacuum level of 5 mm and 11 g or less. . Below, Example 1
After casting and curing in the same manner as above, the resulting propellant was subjected to combustion tests and tensile tests. Table 1 shows the raw material composition, specific impulse measurement results, and tensile speed.

Example 6 A propellant was produced in the same manner as in Example 1, except that 0.16 parts of trimethylolpropane and 0.6 parts of hexamethylene diisocyanate were used, and the resulting propellant was subjected to a combustion test and a tensile test. I did it. Table 1 shows the raw material composition, specific impulse measurement results, and tensile speed.

Comparative Example l 54 parts of NG, 2 parts of stabilizer, 10 parts of diethyl fucrate, and 2.0 parts of lead salicylate were added to the same mixer as in Example 1, and mixed and dehydrated for 1 hour at 40°C and under a vacuum of 5 mm and 11 g or less. A uniform liquid component was obtained. To this mixed solution, 34 parts of NC fine particles having an average particle size of 30 microns were added, and premixing was performed by hand stirring for 5 minutes and under atmospheric pressure for 10 minutes. Further, mixing was performed for 1 hour at 40° C. under a vacuum of 5 mm and 11 g or less to obtain a propellant slurry. Below, Example 1
After casting and curing in the same manner as above, the resulting propellant was subjected to a combustion test and a separate R4 test. Table 1 shows the raw material composition, specific impulse measurement results, and tensile speed.

Comparative Example 2 54 parts of NG, 2 parts of stabilizer, 5 parts of diethyl fucrate, and 2.0 parts of lead salicylate were added to the same mixer as in Example 1.
Namigo dehydration was performed at 40° C. for 1 hour under a vacuum of 5 ms+lIg or less to obtain a uniform liquid component. To this mixed solution, 34 parts of NC (J particles) with an average particle size of 30 microns were added, and premixing was performed by hand stirring for 5 minutes and under atmospheric pressure for 10 minutes. 1 degree
Next, 5 parts of a terminal incyanate polyester compound "Coronate 4076" (manufactured by Nippon Polyester Co., Ltd.) was added, and after premixing by hand stirring for 5 minutes, the mixture was heated at 40°C under a vacuum of 5 m + n11 g or less. Mixing was carried out for 30 minutes.Then, the propellant obtained after casting and curing was performed in the same manner as in Example 1, and a combustion test and a tensile test were conducted.The raw material composition, specific impulse measurement results, and tensile speed are shown in Table 1. show.

Comparative Example 3 59 parts of NG, 2 parts of stabilizer, 9.4 parts of polyethylene glycol, and 2.0 parts of lead salicylate were added to the mixer of Example 1, and partial dehydration was performed for 1 hour at 40°C and a vacuum of 15 mmHg or less. A homogeneous liquid component was obtained. To this mixed solution, 34 parts of Nc1M particles having an average particle size of 30 microns were added, and premixing was performed by hand stirring for 5 minutes and under atmospheric pressure for 10 minutes. Further, the mixture was heated at 40°C for 1 hour under a vacuum of 5 mm and 11 g or less, and then 0.6 parts of hexamethylene diisocyanate was added and premixed by hand stirring for 5 minutes, and then at 40°C and under a vacuum of 5 + + n of 11 g or less. 3 degrees
Mixing was performed for 0 minutes. The propellant obtained after casting and curing was then subjected to a firing test and a tensile test in the same manner as in Example 1. Table 1 shows the raw material composition, specific impulse results, and tensile speed.

Comparative Example 4 Polyether with n=25, m=20, and ε=0 was 8.
35 parts and 0.41 parts of trimethylolpropane.
A propellant was produced in the same manner as in Example 1 except that 1.24 parts of hexamethylene diisocyanate was used, and a combustion test and a tensile test were conducted on the propellant. Raw material composition, specific impulse measurement results,
Table 1 shows the tensile speed.

Comparative Example 5 Polyether with n=5, m=1, β=0 was 6.62
and 0.38 parts of trimethylolpropane,
A propellant was produced in the same manner as in Example 3 except that 3.0 parts of hexamethylene diisocyanate was used, and a combustion test and a tensile test were conducted on the propellant. Table 1 shows the raw material composition, specific impulse measurement results, and bowing speed.

Gelation rate test With the composition of Example 1, in the manufacturing process, 34 parts of NC fine particles with an average particle size of 30 microns were added, and premixing was performed by hand stirring for 5 minutes and under atmospheric pressure for 10 minutes.
After mixing for 1 hour at 0°C and a vacuum of 5 mmHg or less, the propellant slurry before adding hexamethylene diisocyanate was mixed with VISCONICED type (
The viscosity was measured using an instrument (manufactured by Tokyo Keiki Co., Ltd.). The viscosity of the propellant slurry obtained in Comparative Example 1 was also measured in the same manner. The results are shown in the drawing.

NG when polyether according to the present invention is added to NG sensitivity test NG
A 5 kg hammer was used for the drop hammer sensitivity, which shows the sensitivity test results. In addition, the polyether to be used has a value of 0 in the above formula.
, n=25, m=1.

The results are shown in Table 2.

Tatami i222≦≧ Drop mallet sensitivity was determined by JIS K4810-79R Explosives Performance Test.

Examples 1 to 6 are all examples in which polyethers represented by the above general formula according to the present invention were used. Comparative examples 1 and 2.
No. 3 is an example in which the polyether is not used. Comparative example 4.
No. 5 is an example of the polyether in which m+J2 is 11 or more and n is 9 or less.

Examples 1, 2, 4.6 and Comparative Example 1゜2.4, and Examples 3, 5 and Comparative Example 3.5 are nitrocellulose,
The amounts of nitroglycerin, 2-nitrodiphenylamine, and lead salicylate were all the same, and their effects are clear when comparing the Examples and Comparative Examples.

When comparing Example 1 and Comparative Example 2, the specific impulse of the propellant is 231 seconds in Example 1 and 221 seconds in Comparative Example 2, which is actually an increase of 10 seconds. Also, the burning rate is 1.75 times higher. Similarly, Example 3 and Comparative Example 3
When compared, the specific impulse of the propellant is 23 in Example 3.
1 second, and 223 seconds in Comparative Example 3, which shows an increase in specific impulse of 9 seconds, and the burning rate is 1.891 g, which is 1 second.
It can be seen that the effect of increasing the specific impulse and burning rate according to the present invention.

Similarly, when comparing mechanical properties, the strength at high temperatures (σ,) and the elongation at low temperatures (C,) are particularly problematic.
Compared to conventional binders, it is equivalent to that of the non-crosslinked D B tt1-adherent drug of Comparative Example 1, and a remarkable improvement is seen in the strength at high temperatures.

Examples 2 and 3 are examples in which m, n, and 42 of one polyether were varied, but all of them performed satisfactorily. However, in Comparative Example 4, sufficient specific impulse was not obtained, and in Comparative Example 5, elongation at low temperatures was small.

Examples 4 and 5 are examples in which a solid oxidizing agent or combustible aluminum is added, and a high specific impulse is achieved. Example 6 is an example in which the present binder was added in half the amount of actual mni. Achieves high specific impulse and good physical properties.

The gelation rate test shows that this polyether has a fast gelation rate with respect to NC.

Furthermore, based on the NG sensitivity test results, this polyether has NG f
r+X! This reduces sensitivity and increases safety during manufacturing.

As explained in detail above, the polyether of the present invention is
It provides a propellant with high specific impulse, high combustion speed, and good mechanical properties, and is also characterized by excellent manufacturability.

[Brief explanation of drawings]

The drawing shows the gelation rate test results of the propellant slurry before addition of hexamethylene diisocyanate in Example 1 and the propellant slurry of Comparative Example 1.

Claims (2)

[Claims] (1) In double-base propellants whose main components are nitrocellulose and nitroglycerin or liquid nitroester, the raw materials contain 3 to 20% by weight of the general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (in the formula n represents 10 to 50, m+l represents 1 to 10.)
Contains a terminal hydroxyl group aliphatic polyether and isocyanate compound having an azidomethyl group in the side chain represented by
A double-base propellant composition characterized in that a three-dimensional crosslinked product of the terminal hydroxyl group aliphatic polyether and the isocyanate compound is present. (2) In a method for producing a double-base propellant containing nitrocellulose and nitroglycerin or liquid nitroester as the substantial main components, the raw materials further contain 3 to 20%
General formula for weight % ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (In the formula, n represents 10 to 50, and m + l represents 1 to 10.)
A method for producing a double-base propellant composition, characterized in that a hydroxyl-terminated aliphatic polyether and an isocyanate compound having an azidomethyl group in the side chain represented by the formula are present, and the polyether has a three-dimensional crosslinked structure.