RU2241693C1 - Solid rocket fuel - Google Patents

Abstract

FIELD: rocket fuels.

SUBSTANCE: invention provides solid rocket fuel containing plasticizer: nitroisobutyl trinitrate glycerol; oxidant: cyclotetramethylenetetranitroamine or hexanitrohexaazaisovurcitan, and/or hexanitrohexaazaadamantane, and/or ammoniodinitroamide; combustive component: dispersed aluminum and aluminum hydride; high-molecular binder: polybutadiene-nitrile rubber or polyurethane rubber; and process additives.

EFFECT: enabled preparation of low-smoke solid rocket fuel with high impulse and density, low sensibility to mechanical effects, and working temperature range between +50 and -50^оС.

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Description

The invention relates to the field of special technical chemistry, namely to the creation of low-smoke (chlorine-free) high-energy solid rocket fuels (TRT), operated in a wide temperature range (-50 ... + 50 ° C), which can be used in various rocket systems, for example , on the first steps of ballistic missiles, as well as missile defense, air defense, multiple launch rocket systems and other purposes.

TPT is known (US patent No. 5045132, MKI ⁵ C 06 B 45/10, publ. 03.09.91), containing, wt.%:

1.9-dinitro-2,4,6,8-tetranitrazanonan 70

Aliphatic hydroxyl terminated polyester

groups of 10

Trimethylol ethanetrinitrate or 4,4,4-

trinitronitrobutyl nitrate 20

This fuel does not have a sufficiently high level of energy characteristics (I _sp = 261 ... 265 kgf · s / kg at P _k / P _a = 40/1), reduced thermal stability.

TPT is known (US patent No. 3896865, publ. 21.01.74), containing, wt.%:

α-hydro-ω-hydroxypoly- (hydroxymethylene nitramine) 19.20

Hexamethylene diisocyanate 3.80

Aluminum 12.00

Cyclotetramethylene tetranitroamine 65.00

This low-smoke (chlorine-free) TPT has a significant drawback - insufficiently high level of energy characteristics (specific impulse I _sp = 259.8 kgf · s / kg at P _k / P _a ~ 40/1), as well as low resistance in acidic media. In addition, the combustion products of this fuel are characterized by re-ignition in ambient air.

Fuel is also known (US patent No. 4961380, MKI C 06 D5 / 06, publ. 09.10.90) based on ammonium perchlorate, octogen, dispersed aluminum, glycidyl azide polymer, plasticizers - a mixture of 1,5-dinitrate-3-nitroazapentane and 1, 5-diazido-3-nitroazopentane). Fuel has a high single impulse (I _sp = 271, l kgf · s / kg, at P _k / P _a = 40/1), but has an increased sensitivity to moisture, which reduces the reproducibility of the main characteristics of the fuel.

Closest to the claimed technical essence and the result obtained is TRT (RF patent No. 2183608, publ. 06/20/2002), containing, wt.%:

Nitroisobutyl trinitrate glycerol or tetranitromethane 11.22-25.10

Polybutadiene nitrile or polyurethane rubber 2.05-5.90

Cyclotetramethylene tetranitroamine, or

hexanitrohexaazadamantane, or

hexanitrohexaazaisowurtzitan 57.50-84.80

Dispersed aluminum 0.07-20.00

Technological additives 1.50-2.00

A significant disadvantage of this fuel is not sufficiently high level of energy characteristics (calculated specific impulse I _sp = 248,83 ... 263,58 kgf · s / kg, _to at P / P _a = 40/1).

When creating the invention, the task was to develop TRT low-smoke (chlorine-free), with high momentum and density, with combustion products not prone to re-ignition in ambient air, operation in a wide temperature range.

The problem is solved due to the fact that the known composition of solid rocket fuel containing a plasticizer - nitroisobutyl trinitrate glycerin, an oxidizing agent, fuel, high molecular weight binder - polybutadiene nitrile or polyurethane rubber and processing aids, contains cyclotetramethylene tetranitroamine or hexanedi nitride or hexanedi nitride , as fuel - dispersed aluminum and aluminum hydride in the following ratio of components, wt.%:

Nitroisobutyl trinitrate glycerol 11.25-26.78

Polybutadiene nitrile or

polyurethane rubber 2.25-4.72

Cyclotetramethylene tetranitroamine or

hexanitrohexaazaisowurtzitane, and / or

hexanitrohexaazadamantane, and / or

ammonium dinitroamide 35-58

Dispersed aluminum 0.01 - 9.00

Aluminum hydride 6.00-27.00

Technological additives 1.49-1.99

To prepare the proposed TRT use:

- cyclotetramethylene tetranitroamine [OST B81-1509-77], ammonium dinitroamide [TU 84-754-78], hexanitrohexaazaisowurtzitan (GL-20 USA), hexanitrohexaazadamantane [American Morton Thiocol Corporation];

- polybutadiene nitrile rubber SKN-40 [GOST 738-65] or polyurethane rubber SKU-90 [TU 38.403557-87];

- dispersed aluminum [OST B 84-1841];

- aluminum hydride [TU 6-02-881];

- nitroisobutyl trinitrate glycerol [E.Yu. Orlova. Chemistry and technology of blasting explosives. - L .: Chemistry. 1973; L.M. Kozlov, V.N. Burmistrov. Nitro alcohols and their derivatives. KHTI them. S. M. Kirova, Kazan, 1960] or tetranitromethane [E.Yu. Orlova. Chemistry and technology of blasting explosives. - L .: Chemistry. 1973; Ya.M. Paushkin. The chemical composition and properties of jet fuels. - M .: AN USSR. 1958. 376 p.];

- hardeners (sulfur [GOST 127-64], MnO ₂ [TU 6-09-01-718-87], etc.), surfactants (for example, lecithin), etc. can be used as technological additives. Additives are added depending on the fuel composition requirements for a particular rocket engine.

Nitroisobutyl trinitrate glycerol is a heavy oily liquid ρ = 1.68 g / cm ³ , freezing (glass transition) temperature t≤-35 ° C, flash point t = 243 ° C, satisfactory chemical resistance, less volatile than nitroglycerin), superior in power ( heat of explosive conversion) nitroglycerin by 7%:

This compound is a powerful blasting explosive. The energetically active plasticizer nitroisobutyl trinitrate glycerol interacts with high molecular weight binders of increased polarity — SKN-40 polybutadiene rubber or SKU-90 polyurethane rubber — in a wide temperature range of operation (+50 ...- 50 ° С).

Rocket fuel is prepared as follows. The binder is mixed with a plasticizer, fuel, an oxidizing agent and a technological additive (for example, a hardener) are added and mixed in a mixer at a temperature of t = 40 ... 45 ° C for 1.5 ... 2 hours, then it is cured at a temperature of t = 40 ° C for 240 ... 360 hours

An example of a specific implementation of TRT.

The table shows examples of specific compositions of the claimed fuel and the composition of the prototype. The energy characteristics of these compounds are also presented there: specific calculated impulse, density, volume calculated impulse. All limit values of the components of the claimed fuel are directly dependent on the declared limits of any of the oxidizing agents, for example, hexanitrohexaazaisowurtzitane, therefore, the maximum content of the components will be examined using hexanitrohexaazaisowurtzitane as an oxidizing agent. From the example composition 19 of the table it can be seen that the value of I _{sp is} lower than the value of the prototype, that is, if the dosage of hexanitrohexaazaisowurtzitane is lower than the specified limits, then we get the value of I _sp lower than in the prototype, and if we take hexanitrohexaazaisowurtzitane above the stated limit, then TPT will not have acceptable rheological characteristics due to the high degree of volumetric filling of the binder with solid particles of an oxidizing agent. That is, above and below the specified limits of hexanitrohexaazaisowurtzitane it is impractical to take.

From examples 2, 3, 4, 6-18 it follows that the use of nitroisobutyl trinitrate glycerol as an energetically active liquid high-density plasticizer of high molecular weight polymeric binder of increased polarity in the composition of low-smoke (chlorine-free) solid rocket fuel allows (both based on cyclotetramethylene tetranitroamine, and / or hexane azane / or hexanitrohexaazadamantane and / or ammonium dinitroamide) significantly increase the value of the calculated specific impulse.

Aluminum hydride leads to optimization of the component composition, which consists in increasing the hydrogen content and increasing momentum.

Thus, the proposed fuel is low smoke due to the absence of a chlorine-containing component and high energy. The proposed TRT gives combustion products that are not inflammable repeatedly in ambient air, which increases the reliability of the laser guidance system and the absence of surging of the aircraft carrier engine. This is explained by the use of components with a high oxygen balance in the fuel composition, namely nitroisobutyl trinitrate glycerol, which contribute to a more complete oxidation of combustible components. The proposed fuel has high resistance in acidic environments, a wide temperature range of operation, sufficient thermal, hydrolytic stability and low sensitivity to mechanical stress associated with the use of nitroisobutyl trinitrate glycerol in the fuel composition. In addition, the use of the proposed chlorine-free TPT is preferable from an environmental point of view.

Claims (1)

Solid rocket fuel containing a plasticizer, nitroisobutyl trinitrate glycerol, an oxidizing agent, fuel, a high molecular weight binder, polybutadiene nitrile or polyurethane rubber and technological additives, characterized in that it contains cyclotetramethylene tetranitroamine or hexane nitro titanase and hexane nitro titanase - dispersed aluminum and aluminum hydride in the following ratio of components, wt.%: Nitroisobutyl trinitrate glycerol 11.25-26.78 Polybutadiene nitrile or polyurethane rubber 2.25-4.72 Cyclotetramethylene tetranitroamine or hexanitrohexaazaisowurtzitane, and / or hexanitrohexaazadamantane, and / or ammonium dinitroamide 35-58 Dispersed aluminum 0.01 - 9.00 Aluminum hydride 6.00-27.00 Technological additives 1.49-1.99