CN109467495B

CN109467495B - Solid propellant with polyether-butyl hydroxyl block polymer as adhesive

Info

Publication number: CN109467495B
Application number: CN201811599039.4A
Authority: CN
Inventors: 李爽; 侯斌; 贾方娜; 毛羽; 高扬; 程迪
Original assignee: Hubei Institute of Aerospace Chemical Technology
Current assignee: Hubei Institute of Aerospace Chemical Technology
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2020-10-30
Anticipated expiration: 2038-12-26
Also published as: CN109467495A

Abstract

The solid propellant formula with the polyether-butylated hydroxyad segmented polymer as the adhesive is provided, the structure of the polyether-butylated hydroxyad segmented polymer is defined, the polyether-butylated hydroxyad segmented polymer is used as the adhesive to replace butylated hydroxyad lactad hydroxyad propellants, and simultaneously, the components and contents in the propellant are optimally designed, so that the propellant can keep good compatibility with an energetic plasticizer under the condition. In addition, the polyether-butyl hydroxyl block polymer is used as an adhesive, the fluidity of an adhesive melt is obviously increased, cavities and cracks in the propellant can be reduced, and the propellant is helped to pass a slow burning test so as to meet the requirement of low vulnerability of the propellant.

Description

Solid propellant with polyether-butyl hydroxyl block polymer as adhesive

Technical Field

The invention belongs to the technical field of rocket propellants, and particularly relates to a solid propellant for charging a solid rocket engine.

Background

The butyl hydroxyl propellant has the characteristics of excellent comprehensive performance, moderate price and the like, becomes the most widely applied propellant variety in solid rocket engines at home and abroad, and is in the mainstream status of missile weapons. However, the HTPB adhesive itself is a non-energetic material and, because of its low polarity, is not compatible with energetic plasticizers such as nitrates, which limits further improvement of its energetic performance. In addition, the low-vulnerability requirement of the butylated hydroxytoluene propellant cannot be met because the butylated hydroxytoluene adhesive has poor melt fluidity and cannot fill up the holes generated during low-temperature decomposition of ammonium perchlorate, so that the butylated hydroxytoluene propellant can generate violent detonation response in a slow-speed burning test and cannot pass the slow-speed burning test.

With the continuous development of tactical missile weapons in China, in order to further improve the remote hitting capacity of the weapons, the energy performance requirement of an engine on a propellant is further improved, the energy performance of the conventional HTPB propellant cannot meet the technical index requirement of the engine, so that a polyether (code NEPE) propellant plasticized by nitrate is applied to certain key strategic models, but the NEPE high-energy propellant has high production cost and high risk, and the large application of the NEPE high-energy propellant in tactical weapon models is restricted. Therefore, HTPB propellants are still the dominant in domestic and foreign weapons systems.

In addition, because the adhesive of the NEPE propellant is polyether and the molten liquid of the polyether adhesive has good fluidity, the NEPE high-energy propellant can pass a slow-speed burning test, but because the NEPE propellant contains a large amount of explosive and is easy to explode under the action of explosion shock waves, the NEPE propellant cannot meet the requirement of low vulnerability.

In order to improve the energy performance of the HTPB propellant and simultaneously improve the low vulnerability of the propellant, the polyether and the hydroxyl-terminated polybutadiene rubber can be made into a block copolymer. The introduction of the polyether segment can improve the polarity of the adhesive, so as to solve the problem of compatibility of the HTPB adhesive and energetic plasticizers such as nitrate, and the energetic plasticizers are applied to the HTPB propellant, so that the energy performance of the propellant is improved; the introduction of the polyether segment can also improve the fluidity of the adhesive melt, which is beneficial to the propellant using the polyether-butyl hydroxyl block polymer as the adhesive to meet the requirement of low vulnerability of the propellant through a slow burning test.

U.S. Pat. No. 4,989,8913B 1 Gill et al report a hydroxyl-terminated polybutadiene and carboxyl-terminated polyether block polymer synthesized by esterification reaction, the structure of which is shown in formula I.

R in formula I is a polyether segment

The patent mainly introduces the curing, aging and degradation performances of the block polymer film and the plasticizing performance of the block polymer film and an energy-containing plasticizer, and does not relate to the mechanical, process, energy and other performances of a propellant taking a hydroxyl-butyl polyether block polymer as an adhesive.

Zhanelsen in China synthesizes a polyether-butyl hydroxyl segmented polymer through a two-step method, and the structure of the polymer is shown as a formula II.

In formula II, A is a polyether segment

The purpose of the chunshensen synthesis of the block polymer is to improve the water resistance of the polyurethane adhesive, so that the block polymer is only described in the text about the thermal decomposition characteristics and the mechanical properties of the film, and is not applied to the solid propellant.

Zhanwan bin firstly uses HTPB as a macroinitiator, and under the catalytic action of Lewis acid, the active end group of the HTPB is utilized to initiate the ring-opening polymerization of tetrahydrofuran to prepare the polytetrahydrofuran-polybutadiene-polytetrahydrofuran triblock copolymer. The structure of the polymer is shown as formula III.

In the text, a synthesis method of polyether-butadiene block polymer is mainly described, and detailed characterization is carried out on the compound, and film mechanical properties and glass transition temperature of the block polymer are studied, but the block polymer is not applied to solid propellant.

In conclusion, the research on the polyether-block polymer at home and abroad mainly focuses on a synthetic method, and the block polymer is not applied to the solid propellant.

Disclosure of Invention

The invention aims to provide a solid propellant taking a polyether-butylated hydroxyl block polymer as an adhesive, and solves the problems that in the prior art, the butylated hydroxyl adhesive is low in polarity, cannot be compatible with an energetic plasticizer, cannot be further improved in energy performance, and cannot pass a slow-speed burning test.

The technical scheme of the invention is as follows: a solid propellant with polyether-butyl hydroxyl block polymer as an adhesive comprises the following components in percentage by mass: adhesive: 7 to 10.0 percent; curing agent: 0.25 to 1.5 percent; curing catalyst: 0 to 0.04 percent; oxidizing agent: 50.0% -80.0%; energetic additive: 3.0% -15%; metal fuel: 3.0% -23%; plasticizer: 3.0% -10.0%; combustion speed regulator: 0.05-3.0%; bonding agent: 0.05 percent to 0.2 percent; an anti-aging agent: 0.05 percent to 0.3 percent; the adhesive is a polyether-butylated hydroxyl block polymer.

Further, the above polyether-butylene block polymer has a general formula shown below:

wherein, the value of x in the general formula is in the range of 60-80, m is more than or equal to 4, n is more than or equal to 4, and the value of m + n is in the range of 8-30.

Furthermore, the molecular weight of the polyether-butyl hydroxyl block polymer is 4000-7600.

Furthermore, the curing agent is one or a combination of toluene diisocyanate, isophorone and dimer fatty acid diisocyanate.

Further, the curing catalyst is one of triphenyl bismuth, tris (4-ethoxyphenyl) bismuth, tris (3-ethoxyphenyl) bismuth, tris (4-nitrophenyl) bismuth and tris (3-nitrophenyl) bismuth.

Further, the oxidant is one or a combination of Ammonium Perchlorate (AP), Ammonium Nitrate (AN) and potassium nitrate (KP); the energetic additive is one or a combination of HMX, RDX and CL-20; the metal fuel is one or a combination of Al powder or Mg powder.

Further, the plasticizer is one or a combination of diisooctyl sebacate (DOS), dioctyl adipate (DOA), dioctyl phthalate (DOP), butyl nitroethyl nitramine (Bu-NENA), a bis 2, 2-dinitropropanol formal/bis 2, 2-dinitropropanol acetal mixture (3A) and triethylene glycol dinitrate (TEGDN).

Further, the combustion speed regulator is CuO, CuS or Cr₂O₃、PbCrO₄、Fe₂O₃Calcium carbonate, calcium fluoride, magnesium fluoride, strontium carbonate, magnesium carbonate, ammonium oxalate, octyl ferrocene (T27), butyl ferrocene, 2- (bisethylferrocenyl) propane (GFP).

Further, the bonding agent is one or more of MAPO (tris [1- (2-methyl) aziridinyl ] phosphine oxide), HX-752 (isophthaloyl propyleneimine), tetraethylenepentamine, BIDE (butyldiethanolamine), TEA (triethanolamine), triethanolamine boron trifluoride complex, tetrahydroxyethylethylenediamine, and TETAN (triethylenetetramine).

Further, the antioxidant is antioxidant H (N, N' -diphenyl-p-phenylenediamine), A₀-2246(2, 2' -methylene-bis- (4-methyl-6-tert-butylphenol)), MNA (N-methyl-2-nitroaniline), Hs (thiobis- (3, 5-ditert-butyl-4-hydroxybenzyl)).

Compared with the prior art, the technical scheme of the invention has the following beneficial effects:

(1) the polyether-butadiene block polymer is used for replacing butadiene rubber in the butadiene propellant as the adhesive of the solid propellant, the structure and the molecular weight range of the block polymer are given, the compatibility of the adhesive and the energetic plasticizer can be improved by using the block polymer, and the energetic plasticizer can be applied to the propellant, so that the melting characteristic and the energy performance of the propellant are improved.

(2) The polyether-butadiene block polymer is used as the adhesive of the solid propellant instead of butadiene rubber in the butadiene propellant, so that the compatibility of the adhesive and an energetic plasticizer can be improved, the energy performance of the propellant is improved, the fluidity of the molten adhesive can be improved, the low-vulnerability performance of the propellant can be improved through a slow-speed burning test.

(3) The polyether-butadiene block polymer is used as an adhesive of the solid propellant instead of butadiene rubber in the butadiene propellant, the structure of the block polymer is given, other components and content of the propellant are optimized, the energy performance of the propellant can be improved, the low-vulnerability performance of the propellant is improved, and meanwhile, the propellant has good technological performance and certain mechanical performance.

The invention improves the low vulnerability of the propellant under the condition of not damaging the prior propellant system; the compatibility of the adhesive and the energetic plasticizer is improved, so that the energy performance of the propellant is improved; and the propellant keeps good technological property and certain mechanical property.

Drawings

These and/or other aspects and advantages of the present invention will become more apparent and more readily appreciated from the following detailed description of the embodiments of the invention, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a photograph of a film of a polyether-butadiene block polymer according to an embodiment of the present invention in a molten state at a high temperature of 400 ℃;

FIG. 2 is a photograph of a film of butylated hydroxyanisole in a molten state at a high temperature of 400 ℃;

FIG. 3 is a photograph showing the melt state of a polyether-butadiene block polymer film of an embodiment of the present invention at a high temperature of 400 ℃.

Detailed Description

In order that those skilled in the art will better understand the present invention, the following detailed description of the invention is provided in conjunction with the accompanying drawings and the detailed description of the invention.

Example 1

A solid propellant takes a polyether-hydroxyl-terminated block polymer as an adhesive, and the structure of the polyether-hydroxyl-terminated block polymer is as follows:

wherein the value of m is within the range of 8-12.

The propellant formulation with the block polymer as binder (the components in mass percent) is shown in table 1:

TABLE 1 propellant formulations with polyether-butadiene block polymers as binders

Formulation composition	Mass percent%
		Polyether-butadiene block polymers	7.79
TDI	0.39
		AP	69.0
Al	18.0
		DOA	4.1
T27	0.5
		TPB	0.01
Others	0.21

The mixing and casting process of the propellant with the polyether-hydroxyl-terminated block polymer as the adhesive is similar to that of the general hydroxyl-terminated propellant, and the curing process is also consistent (namely, the curing process is carried out for 7 days at 50 ℃). The processing properties of the propellant slurry obtained and the mechanical properties of the propellant are shown in tables 2 and 3. TABLE 2 propellant slurries with polyether-butylated Hydrocarbon Block polymers as binders for Process Performance test results

Note: η in Table 2 is the viscosity and τ y is the yield value, as measured by a rotational viscometer.

TABLE 3 mechanical Properties of propellants with polyether-butylated Hydrocarbon Block polymers as binders

Note: σ in Table 3_mThe maximum tensile strength,_mMaximum elongation,_bElongation at break.

It can be seen from tables 2 and 3 that, after the hydroxyl rubber in the hydroxyl propellant is replaced by the polyether-hydroxyl-terminated segmented polymer, the propellant still maintains good technological properties and mechanical properties, and can meet the requirements of practical application.

The film using the polyether-hydroxyl-terminated block polymer as the adhesive is heated to 400 ℃, the melting characteristic of the film is observed, and compared with the film of hydroxyl under the same condition, the photograph of the film of polyether-hydroxyl-terminated block polymer in the melting state at 400 ℃ is shown in figure 1, and the photograph of the film of hydroxyl-terminated block polymer in the melting state at 400 ℃ is shown in figure 2.

As can be seen from FIGS. 1 and 2, the polyether-butadiene block polymer film becomes a liquid with good fluidity after being heated, while the butadiene film becomes hard and brittle; the characteristic of the polyether-butyl hydroxyl block polymer is beneficial to the propellant to pass a slow burning test, and the low vulnerability of the propellant is improved.

Example 2

The solid propellant takes polyether-butyl hydroxyl block polymer as an adhesive, and has the structure as follows:

wherein the value of m is within the range of 8-12.

The propellant formulation with the block polymer as binder (the components in mass percent) is shown in table 4:

TABLE 4 propellant formulations with polyether-butadiene block polymers as binders

Due to the addition of the polyether-hydroxyl-butyl block and the energetic plasticizer, the oxygen content in the propellant is increased, a certain amount of ammonium nitrate explosive can be increased, and meanwhile, the propellant can still keep higher combustion efficiency. The energy performance of the propellant obtained by theoretical calculation is shown in table 5, and the energy performance of the butylated hydroxytoluene propellant with the solid content of 88% and the Al powder content of 18.5% is also listed in table 5.

TABLE 5 thermodynamic theoretical calculation of propellant formulations

Note: conditions for theoretical calculation: at 25 ℃, Pc is 6.86MPa, Pa is 1.01325 MPa; c in table 5 is the characteristic velocity;

is a specific impulse.

As can be seen from table 5, the propellant with the polyether-butylated hydroxyl block polymer as the binder has significantly higher energy performance, both in density and theoretical specific impulse, than the conventional butylated hydroxyl propellant.

The processing properties of the propellant containing the polyether-butadiene block polymer as the binder of this example are shown in Table 6.

TABLE 6 propellant processing Properties with polyether-butadiene block Polymer as adhesive

Note: eta in Table 6 is viscosity,. tau_yTo yield value, it was tested by rotational viscometer.

As can be seen from table 6, the propellant still maintains good process performance.

Example 3

wherein the value of m is in the range of 11-15.

The propellant formulation with the block polymer as binder (components in mass percent) is shown in table 7:

TABLE 7 propellant formulations with polyether-butadiene block polymers as binders

Formulation composition	Mass percent%
		Polyether-butadiene block polymers	7.76
TDI	0.40
		AP	58.0
HMX	10.0
		Al	19.0
TEGDN	4.6
		TPB	0.01
MAN	0.07
		Others	0.16

The energy performance of the propellant obtained by theoretical calculation is shown in table 8, and the energy performance of the butylated hydroxytoluene propellant with the solid content of 88% and the Al powder content of 18.5% is also listed in table 8.

TABLE 8 thermodynamic theoretical calculation of propellant formulations

Note: conditions for theoretical calculation: at 25 ℃, Pc is 6.86MPa, Pa is 1.01325 MPa; c in table 8 is the characteristic velocity;

is a specific impulse.

As can be seen from table 8, the propellant density and theoretical specific impulse for the polyether-butylated hydroxyl block polymer as a binder are significantly higher than for the conventional butylated hydroxyl propellant, the energy performance of the propellant is significantly increased.

The film made of the block polymer was heated to 400 ℃ and the state thereof was as shown in FIG. 3. As can be seen from FIG. 3, the melt flowability of the film made of the block polymer is better than that of the butylated hydroxytoluene, and the low-vulnerability characteristic of the propellant can be improved remarkably.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A solid propellant with a polyether-butadiene block polymer as a binder is characterized in that: comprises the following components in percentage by mass:

adhesive: 7 to 10.0 percent;

curing agent: 0.25 to 1.5 percent;

curing catalyst: 0 to 0.04 percent;

oxidizing agent: 50.0% -80.0%;

energetic additive: 3.0% -15%;

metal fuel: 3.0% -23%;

plasticizer: 3.0% -10.0%;

combustion speed regulator: 0.05-3.0%;

bonding agent: 0.05 percent to 0.2 percent;

an anti-aging agent: 0.05 percent to 0.3 percent;

the adhesive is a polyether-butylated hydroxyl block polymer;

the polyether-butadiene block polymer has the general formula shown below:

wherein in the general formula, x is within the range of 60-80, m is more than or equal to 4, n is more than or equal to 4, and m + n is within the range of 8-30;

the molecular weight of the polyether-butylated hydroxyl block polymer is 4000-7600;

the plasticizer is one or a combination of butyl nitrooxyethyl nitramine, a mixture of bis 2, 2-dinitropropanol formal and bis 2, 2-dinitropropanol acetal, and triethylene glycol dinitrate.

2. The solid propellant of claim 1 having a polyether-butadiene block polymer as a binder, wherein: the curing agent is one or a combination of toluene diisocyanate, isophorone diisocyanate and dimer fatty acid diisocyanate.

3. The solid propellant of claim 1 wherein the polyether-butadiene block polymer is a solid propellant comprising: the curing catalyst is one of triphenyl bismuth, tri (4-ethoxyphenyl) bismuth, tri (3-ethoxyphenyl) bismuth, tri (4-nitrophenyl) bismuth and tri (3-nitrophenyl) bismuth.

4. The solid propellant of claim 1 wherein the polyether-butadiene block polymer is a solid propellant comprising: the oxidant is one or a combination of ammonium perchlorate, ammonium nitrate and potassium nitrate; the energetic additive is one or a combination of HMX, hexogen and hexanitrohexaazaisowurtzitane; the metal fuel is one or a combination of Al powder or Mg powder.

5. The solid propellant of claim 1 wherein the polyether-butadiene block polymer is a solid propellant comprising: the combustion speed regulator is CuO, CuS and Cr₂O₃、PbCrO₄、Fe₂O₃Calcium carbonate, calcium fluoride, magnesium fluoride, strontium carbonate, magnesium carbonate, ammonium oxalate, octyl ferrocene, butyl ferrocene, 2- (bisethylferrocenyl) propane or a combination thereof.

6. The solid propellant of claim 1 wherein the polyether-butadiene block polymer is a solid propellant comprising: the bonding agent is one or more of tris [1- (2-methyl) aziridinyl ] phosphine oxide), isophthaloyl propyleneimide, tetraethylenepentamine, butyldiethanolamine, triethanolamine boron trifluoride complex, tetrahydroxyethyl ethylenediamine and triethylene tetramine.

7. The solid propellant of claim 1 wherein the polyether-butadiene block polymer is a solid propellant comprising: the anti-aging agent is one or more of anti-aging agents H (N, N '-diphenyl-p-phenylenediamine), 2, 2' -methylene-bis- (4-methyl-6 tert-butyl phenol), N-methyl-2-nitroaniline and Hs (thio-bis- (3, 5-di-tert-butyl-4-hydroxybenzyl)).