Search

CN-118307744-B - Double-curing system high-temperature-resistant resin for solid rocket engine and preparation method thereof

CN118307744BCN 118307744 BCN118307744 BCN 118307744BCN-118307744-B

Abstract

The invention relates to the technical field of solid rocket engines, and discloses a dual-curing system high-temperature-resistant resin for a solid rocket engine and a preparation method thereof. The preparation method comprises the steps of grafting polyfunctional epoxy resin through azido, obtaining azido modified polyfunctional epoxy resin, modifying polyfunctional aromatic amine through alkynyl, obtaining alkynyl modified aromatic amine epoxy curing agent, mixing azido modified polyfunctional epoxy resin and alkynyl modified aromatic amine epoxy curing agent, obtaining mixed resin, adding reactive diluent, catalyst and accelerator, and curing by using curing program, thus obtaining the dual-curing-system high-temperature-resistant resin.

Inventors

  • HU MINGJIE
  • HUANG CHI
  • LIAO JUN
  • CHEN HAO
  • HU WEI

Assignees

  • 湖北航泰科技有限公司

Dates

Publication Date
20260508
Application Date
20240426

Claims (8)

  1. 1. The preparation method of the dual-curing system high-temperature resistant resin for the solid rocket engine is characterized by comprising the following steps of: The method comprises the steps of grafting polyfunctional epoxy resin through azido, obtaining azido modified polyfunctional epoxy resin, wherein the grafting mode of the azido grafted polyfunctional epoxy resin is that epoxy groups of the polyfunctional epoxy resin are partially subjected to SN2 substitution ring-opening reaction with sodium azide, and an intermediate subjected to SN2 substitution ring-opening reaction is subjected to end-capping reaction by epichlorohydrin, so that azido modified polyfunctional epoxy resin is obtained, and the molar ratio of the sodium azide to the epoxy groups of the polyfunctional epoxy resin is 1 (1-50); the method for modifying the alkynyl modified aromatic amine epoxy curing agent comprises the steps of carrying out SN2 substitution reaction on the aromatic amine curing agent and propargyl bromide, and then washing to remove halogen, so as to obtain the alkynyl modified aromatic amine epoxy curing agent, wherein the molar ratio of the propargyl bromide to the amino active hydrogen of the aromatic amine curing agent is 1 (10-50); Mixing azido modified polyfunctional epoxy resin and alkynyl modified aromatic amine epoxy curing agent to obtain mixed resin, adding reactive diluent, catalyst and accelerator, and curing by using a curing program to obtain the dual-curing system high-temperature resistant resin.
  2. 2. The method for preparing the dual-curing-system high-temperature-resistant resin for the solid rocket engine, according to claim 1, wherein the polyfunctional epoxy resin comprises one or more of TDE-85, AFG-90 and AG-80, and the aromatic amine curing agent comprises one or more of m-phenylenediamine, m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone and o-xylylenediamine.
  3. 3. The method for preparing a dual-curing-system high-temperature-resistant resin for a solid rocket engine as recited in claim 1, wherein the reactive diluent comprises one or more of ethylene glycol diglycidyl ether, pentaerythritol tetraglycidyl ether and trimethylolpropane triglycidyl ether.
  4. 4. The method for preparing a dual-curing-system high-temperature-resistant resin for a solid rocket engine according to claim 1, wherein the reactive diluent is added to adjust the epoxy value of the mixed resin so that the molar ratio of the azido group to the alkynyl group is (0.98-1.02): 1, and the molar ratio of the epoxy group to the amino active hydrogen is (0.95-1.05): 1.
  5. 5. The preparation method of the dual-curing-system high-temperature-resistant resin for the solid rocket engine, which is disclosed in claim 1, is characterized in that the accelerator comprises one or more of imidazole, 2-ethyl-4-methylimidazole, 2-methylimidazole and 2-ethylimidazole, and the mass of the accelerator is 0.8-1.2% of the mass of the mixed resin.
  6. 6. The preparation method of the dual-curing-system high-temperature-resistant resin for the solid rocket engine, which is disclosed in claim 1, is characterized in that the catalyst comprises one or more of triphenylphosphine cuprous bromide and triphenylphosphine cuprous chloride, and the mass of the catalyst is 0.2-0.5% of the mass of the mixed resin.
  7. 7. The method for preparing the dual-curing-system high-temperature-resistant resin for the solid rocket engine as recited in claim 1, wherein the curing procedure is specifically a multi-step curing process of low-temperature curing, medium-high-temperature curing and high-temperature curing; The low-temperature curing is the preliminary reaction of epoxy groups and aromatic amino groups, the medium-temperature curing is the addition of alkynyl groups and azido groups to generate a polytriazole system, and the high-temperature curing is the further reaction of epoxy groups and residual amino groups; The curing system of the curing program is 65 ℃ 180min-120 ℃ 240min-160 ℃ 720min.
  8. 8. A dual cure system high temperature resistant resin for solid rocket engines, characterized by being prepared by the method of any one of claims 1-7.

Description

Double-curing system high-temperature-resistant resin for solid rocket engine and preparation method thereof Technical Field The invention relates to the technical field of solid rocket engines, in particular to a dual-curing system high-temperature-resistant resin for a solid rocket engine and a preparation method thereof. Background In order to improve engine efficiency and reduce negative quality, large-sized solid rocket engines are generally formed by adopting a wet winding process, and the resin of the solid rocket engines is usually an epoxy resin system. However, the conventional epoxy resin system has low heat resistance, and the performance of the epoxy resin system is rapidly reduced under the aerodynamic heat in the rocket flight process, so that the overall safety of the engine is affected. The application of a curing system of the polyfunctional epoxy resin and the aromatic polyamine is an effective means for improving the heat resistance of the wet winding epoxy resin, and the curing system has higher heat resistance due to the fact that the system contains a large number of benzene rings with high rigidity and higher crosslinking degree. Due to the limit of heat resistance of the epoxy resin system, the glass transition temperature of the epoxy resin system suitable for wet winding, which can be applied at present, is not more than 220 ℃, and the technical requirements of new-generation weapon models and high-thrust carrier rockets cannot be met. The polytriazole resin is a polymer which utilizes 1,3 dipolar cycloaddition reaction of azido and alkynyl click chemical reaction, and has higher heat resistance as the main chain of the polymer contains a large number of rigid triazole ring structures, and the glass transition temperature can reach more than 350 ℃. However, the monomer of polytriazole, aromatic azide and aryne have high molecular structure regularity and high molecular chain rigidity, so that the monomer is in a solid state in the range of normal temperature to 70 ℃ and cannot be directly applied to wet winding of a carbon fiber shell of a solid rocket engine, a conventional use method is to add a certain amount of solvent to dissolve the monomer into low-viscosity liquid, the addition of the solvent causes extremely worsening of winding working environment on one hand and greatly increases product cost on the other hand, and most importantly, the addition of the solvent causes easy generation of bubbles in the subsequent curing process to cause internal defects of the product, and possibly causes disastrous quality accidents. Therefore, the dual-curing system high-temperature resistant resin for the solid rocket engine needs to be prepared, and the problems that the epoxy resin system is low in heat resistance and the polytriazole resin cannot be directly applied to wet winding of a carbon fiber shell of the solid rocket engine are solved. Disclosure of Invention Based on the above, the invention aims to provide the dual-curing system high-temperature resistant resin for the solid rocket engine and the preparation method thereof, which overcome the defects of insufficient heat resistance and poor technological performance of the existing resin system for wet winding, and remarkably improve the heat resistance of the existing epoxy resin system, thereby improving the heat resistance of the carbon fiber shell material. In order to achieve the above purpose, the invention adopts the following technical scheme: The preparation method of the dual-curing system high-temperature resistant resin for the solid rocket engine comprises the following steps: Grafting the polyfunctional epoxy resin through azido groups to obtain azido modified polyfunctional epoxy resin; modifying the multifunctional aromatic amine through alkynyl to obtain an alkynyl modified aromatic amine epoxy curing agent; Mixing azido modified polyfunctional epoxy resin and alkynyl modified aromatic amine epoxy curing agent to obtain mixed resin, adding reactive diluent, catalyst and accelerator, and curing by using a curing program to obtain the dual-curing system high-temperature resistant resin. As a preferred scheme of the preparation method of the dual-curing system high-temperature resistant resin for the solid rocket engine, the grafting mode of the azido grafted polyfunctional epoxy resin is that epoxy chloropropane is used for end capping reaction of an intermediate after SN2 substitution ring opening reaction of partial epoxy groups of the polyfunctional epoxy resin and sodium azide, so that the azido modified polyfunctional epoxy resin is obtained, the reaction mechanism is shown in a figure 1, and the molar ratio of the sodium azide to the epoxy groups of the polyfunctional epoxy resin is 1 (1-50). As a preferred scheme of the preparation method of the dual-curing-system high-temperature-resistant resin for the solid rocket engine, the modification method of the alkynyl modified aromatic amine epoxy curing ag