Self-healing energetic binder and method for its preparation

Abstract

The application belongs to the field of polymer materials and energetic materials, and discloses a preparation method and application of a self-repairing energetic adhesive.The adhesive is composed of an anionic copolymer emulsion and a cationic copolymer emulsion; after the anionic emulsion and energetic crystals synthesized in the application are stirred uniformly in water, a crosslinking agent and the cationic emulsion are added, and the stirring is continued, the cationic emulsion is used to break the emulsion in the coating system, and the energetic crystals are coated, then the adhesive is filtered, dried, and then pressed into a mold to be cured at room temperature for a period of time to obtain a self-repairing energetic composite material.The application solves the problems that the traditional energetic adhesive needs to use organic solvents in synthesis and needs to add a demulsifier to break the emulsion and introduce impurities; meanwhile, the self-repairing performance of the adhesive effectively solves the problem that the traditional energetic adhesive cannot self-repair microcracks, and the microcracks can be self-healed.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials and energetic materials, and specifically relates to a self-healing energetic adhesive and its preparation method. Background Technology

[0002] In recent years, numerous explosions involving energetic materials have highlighted their safety issues. With the increasing energy density of energetic materials, greater emphasis needs to be placed on improving their insensitivity to enhance the survivability of weapon systems on the battlefield and the safety of ammunition storage, transportation, and handling.

[0003] Currently, polymer binders have undergone several generations of development, evolving from polyisobutylene, nitroglycerin-plasticized nitrocellulose, polyacrylates, and fluororubber to commonly used polyurethane systems such as isocyanate and hydroxyl-terminated polybutadiene (HTPB), and energetic binders such as glycidyl azide (GAP). The binder content in PBX is typically 10%. As a special high-filler composite material, the properties of explosive particles, binders, and interfacial bonding significantly affect the mechanical properties of PBX and the desensitizing effect of the binder. Currently, polyurethane bonding systems, represented by HTPB and GAP, have achieved significant results in improving energy output and optimizing reaction control. However, during storage and transportation, environmental factors, stress, and material aging can lead to microcracks in PBX, damaging the integrity of the explosive charge structure and causing performance degradation and safety risks. Furthermore, most commonly used energetic binders use organic solvents in their synthesis, which have a certain environmental impact. Using a water suspension granulation process achieves "zero" organic solvent addition, providing a safe, efficient, and solvent-free green manufacturing process for PBX.

[0004] Therefore, providing a self-healing energetic adhesive is of great significance for preventing microcracks in PBX, improving safety, and promoting green manufacturing processes. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a self-healing energetic adhesive, which is composed of anionic copolymer emulsion and cationic copolymer emulsion. The anionic copolymer emulsion and cationic copolymer emulsion are obtained by emulsion polymerization of a monomer mixture containing energetic monomers, hydrophilic monomers, lipophilic monomers and ionic monomers. Furthermore, the adhesive contains a crosslinking agent with dynamically reversible chemical bonds to form a crosslinked network structure with self-healing capabilities.

[0006] The energetic monomer is selected from at least one of the azidoacrylate monomers, preferably 2-azidoethyl methacrylate, 1-azidoisopropyl methacrylate, 2-azidoethyl acrylate, 1-azidoisopropyl acrylate, or 3-azido-2,2-bis(azidomethyl)propyl methacrylate.

[0007] The anionic copolymer emulsion contains ionic monomers selected from at least one of acrylic acid, methacrylic acid, and their sodium or potassium salts; the cationic copolymer emulsion contains ionic monomers selected from at least one of dimethylaminoethyl acrylate and dimethylaminoethyl methacrylate quaternary ammonium salt.

[0008] The hydrophilic monomer is selected from at least one of hydroxyethyl acrylate and acrylamide;

[0009] The lipophilic monomer is selected from at least one of butyl acrylate, isooctyl acrylate, methyl methacrylate, styrene, and glycidyl methacrylate.

[0010] The crosslinking agent is an amine or acid compound containing disulfide bonds, preferably 4,4'-diaminodiphenyl disulfide, 2,2'-diaminodiphenyl disulfide, or 2,2'-dithiodiethylamine dihydrochloride, or 3,3'-dithiodialanine.

[0011] In the adhesive, the energetic monomer accounts for 0% to 70% of the total monomer mass, preferably 10% to 50%; the glass transition temperature (T) of the copolymer... g The temperature range is -20℃ to 20℃, preferably -10℃ to 10℃.

[0012] The energetic crystal is selected from at least one of RDX, HMX, and TNT.

[0013] The purpose of this invention is to address the existing problems by providing a method for preparing a self-healing energetic adhesive, specifically including the following steps:

[0014] (1) Take the self-made energetic monomer 2-azidoethyl methacrylate (AzEMEA) for later use (energetic monomers also include 1-azidoisopropyl methacrylate (AzPMEA), 2-azidoethyl acrylate (AzEACE), 1-azidoisopropyl acrylate (AzPACE) and 3-azido-2,2-bis(azidomethyl)propyl methacrylate (3AzEMEA)).

[0015] (2) Preparation of anionic copolymer emulsion A: Take the energetic monomers and some anionic monomers (acrylic acid (AA), methacrylic acid and its sodium and potassium salts (SMAA / KMAA), hydrophilic monomer hydroxyethyl acrylate (HEA), lipophilic monomers (butyl acrylate (BA), isooctyl acrylate (2-EHA), methyl methacrylate (MMA), glycidyl methacrylate (GMA)) and emulsifier and water from step 1) and put them into a reaction vessel and heat them up. Add chain transfer agent and stir continuously. When the temperature reaches 80°C, add some initiator and reducing agent to start free radical emulsion polymerization.

[0016] (3) Add the remaining monomers, initiators and reducing agents in batches. After the addition is completed, raise the temperature to 85°C to continue the reaction.

[0017] After cooling to 40℃ and holding at that temperature for a period of time, a stable anionic copolymer emulsion A is obtained.

[0018] (4) Preparation of cationic copolymer emulsion B: Take the energetic monomers and some cationic monomers (dimethylaminoethyl acrylate (DMA), dimethylaminoethyl methacrylate quaternary ammonium salt (DMEA-Q)), hydrophilic monomer acrylamide (AM) and lipophilic monomers (butyl acrylate (BA), isooctyl acrylate (2-EHA), methyl methacrylate (MMA), glycidyl methacrylate (GMA)) and emulsifier and water from step 1) and put them into the reaction vessel and heat them up. Add chain transfer agent and stir continuously. When the temperature reaches 80°C, add some initiator and reducing agent to start free radical emulsion polymerization.

[0019] (5) Add the remaining monomers, initiators and reducing agents in batches. After the addition is completed, raise the temperature to 85°C to continue the reaction.

[0020] After cooling to 40℃ and holding at that temperature for a period of time, a stable cationic copolymer emulsion B is obtained.

[0021] (6) After stirring the anionic emulsion A and the energetic crystal evenly, add the crosslinking agent and the cationic emulsion B, continue stirring, break the emulsion and coat the energetic crystal, filter, dry, and then put it into a mold to press and shape. After curing at room temperature for a period of time, the self-healing energetic composite material is obtained.

[0022] The following are the preferred conditions for the corresponding process steps in the above synthesis process:

[0023] Preferably, the chain transfer agent in steps (2) and (4) is n-dodecyl mercaptan, and the added mass is 0.1-0.5 wt% of the monomer in step (1).

[0024] Preferably, the emulsifier in steps (2) and (4) is prepared by mixing nonionic emulsifier OP-50 and ionic emulsifier CO-436, with a mass ratio of OP-50 to CO-436 of 1:1, and the mass of emulsifier added is 0.1-5.0 wt% of the monomer in step (2).

[0025] Preferably, the initiator in steps (2) and (4) is ammonium persulfate and azobisisobutyramidine hydrochloride, the reducing agent is sodium thiosulfate, the added mass of ammonium persulfate and sodium thiosulfate is 0.5 wt% of the monomer in step (2), and the added mass of azobisisobutyramidine hydrochloride is 0.1-0.2 wt% of the monomer in step (2).

[0026] Preferably, the glass transition temperature of the polymer in steps (2) and (4) is designed using the Fox formula to determine the mass fraction of monomers AA / SMAA / KMAA, DMA / DMEA-Q, HEA / AM, BA, 2-EHA, MMA, and GMA, and the mass fraction of energetic monomers added is 0 to 50 wt% of the monomers in step (2).

[0027]

[0028] Preferably, the batch additions in steps (3) and (5) are added every 20 minutes, and the addition is completed within 3 hours, with a heat preservation time of 30 minutes.

[0029] Preferably, the reaction time in steps (3) and (5) is 4 hours and the stirring speed is 200 r / min.

[0030] Preferably, the crosslinking agent in step 6) is 4,4'-diaminodiphenyl disulfide (C), 2,2'-diaminodiphenyl disulfide (D), or 3,3'-dithiodialanine (E), and the amount added is 0 to 100% of the molar amount of epoxy groups in the emulsion polymer.

[0031] Preferably, in step (6), the ratio of energetic crystal to polymer is 1:1 to 20:1, preferably 4:1 to 9:1, and the energetic crystal is RDX.

[0032] Compared with the prior art, the present invention has the following advantages and outstanding effects:

[0033] 1. Since the method for preparing self-healing energetic adhesives in this invention is free radical emulsion polymerization, compared with the preparation of energetic adhesives by ring-opening polymerization involving organic solvents, this invention achieves a "zero" organic solvent emulsion polymerization system, thus optimizing the green preparation process of energetic adhesives.

[0034] 2. Because the present invention utilizes a crosslinking agent containing disulfide bonds for post-curing reaction to construct a crosslinking network structure interwoven with disulfide bonds and ionic bonds, PBX has excellent and stable mechanical properties, solving the problem of poor mechanical properties of PBX prepared by conventional adhesives.

[0035] 3. By introducing azide-based energetic segments, the copolyacrylate adhesive is endowed with energetic properties, thereby improving the burst performance of PBX.

[0036] 4. The reversible displacement reaction of disulfide bonds in the crosslinking agent and the large number of hydrogen bonds in the system allow for dynamic and reversible exchange reactions of disulfide bonds (-SS-) at damaged sites of the material under room temperature or slight heating conditions, reconnecting broken molecular chains. Simultaneously, the abundant hydrogen bonds between polymer chains can also reform at the interface. The synergistic effect of these two factors enables the self-healing of microcracks, giving PBX prepared by this adhesive system a certain degree of self-repairing ability. It can self-repair after microcracks are generated in the material, reducing microcracks in PBX during production, storage, and transportation, extending the service life of the material, and possessing both energetic and self-healing effects. Attached Figure Description

[0037] Figure 1 Diagram of the self-healing process of this invention.

[0038] Figure 2 The stress-strain curves of the damaged and undamaged adhesives of this invention.

[0039] Figure 3 The present invention contains the H-spectrum NMR of energetic monomers.

[0040] Figure 4 Infrared spectra of energetic monomers in this invention.

[0041] Figure 5 A schematic diagram of crosslinking in this invention. Detailed Implementation

[0042] The following embodiments are given in conjunction with the accompanying drawings, and the present invention is described in detail. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description, which still fall within the scope of protection of the present invention.

[0043] Example 1

[0044] This example provides a method for preparing a self-healing energetic adhesive (sample 1), which specifically includes the following steps:

[0045] (1) Dissolve 1g of OP-50 and 1g of CO-436 in 16g of water and stir until homogeneous to prepare an emulsifier solution for later use. Add polymer T... gThe temperature was set to 0℃, and the amount of energetic monomer added was 30 wt% of the total monomers. The mass of other monomers added was determined using the Fox formula. A pre-emulsion was prepared by mixing 0.27 g acrylic acid, 3.8 g hydroxyethyl acrylate, 3.36 g butyl acrylate, 14.5 g isooctyl acrylate, 4.26 g methyl methacrylate, 12 g 2-azidoethyl methacrylate, 2 g glycidyl methacrylate, 7.2 g water, and 12.8 g emulsifier solution. An initiator solution was prepared by adding 0.2 g ammonium persulfate, 0.2 g sodium thiosulfate, and 0.08 g azobisisobutyramidine hydrochloride to three stoppered test tubes, and then adding 10 g water to each stoppered test tube. Take 10g of seed emulsion, 3.2g of emulsifier solution and 26.8g of water and mix them in a reaction vessel. Stir for 10 minutes and then heat the system to 80℃. Then add 1 / 10 of the pre-emulsion and 1 / 3 of the initiator solution and react for 30 minutes.

[0046] (2) Add the remaining 9 / 10 of the pre-emulsion and 2 / 3 of the initiator solution every 20 minutes, and finish adding them within 3 hours. Then react for another 4 hours after adding them.

[0047] (3) Cool down to 40℃ and keep warm for 30 min to obtain stable anionic copolymer emulsion A.

[0048] (4) Dissolve 1g of OP-50 and 1g of CO-436 in 16g of water and stir until homogeneous to prepare an emulsifier solution for later use. Add polymer T... g The temperature was set to 0℃, and the amount of energetic monomer added was 30 wt% of the total monomers. The mass of other monomers added was determined using the Fox formula. A pre-emulsion was prepared by mixing 1.83 g acrylamide, 0.46 g dimethylaminoethyl acrylate, 17.8 g isooctyl acrylate, 3.31 g butyl acrylate, 2.52 g methyl methacrylate, 12 g 2-azidoethyl methacrylate, 2 g glycidyl methacrylate, 7.2 g water, and 12.8 g emulsifier solution. An initiator solution was prepared by adding 0.2 g ammonium persulfate, 0.2 g sodium thiosulfate, and 0.08 g azobisisobutyramidine hydrochloride to three stoppered test tubes, and then adding 10 g water to each stoppered test tube. Take 10g of seed emulsion, 3.2g of emulsifier solution and 26.8g of water and mix them in a reaction vessel. Stir for 10 minutes and then heat the system to 80℃. Then add 1 / 10 of the pre-emulsion and 1 / 3 of the initiator solution and react for 30 minutes.

[0049] (5) Add the remaining 9 / 10 of the pre-emulsion and 2 / 3 of the initiator solution every 20 minutes, and finish adding them within 3 hours. Then react for another 4 hours after adding them.

[0050] (6) Cool down to 40°C and keep warm for 30 minutes to obtain stable cationic copolymer emulsion B.

[0051] (7) Take 2g of emulsion A from step 4), add 2.4g of RDX to it, and stir evenly. Then take 0.026g of crosslinking agent 4,4'-diaminodiphenyl disulfide (the molar ratio of crosslinking agent amine group to polymer epoxy group is 1:1) and disperse it in the coating system. Then take 2g of emulsion B from step (6) and mix it evenly with the crosslinking agent solution, and add it dropwise to the above emulsion A. Continue stirring for 15min, filter and place it in a mold, and place it in a ventilated place to cure at room temperature for 72h to obtain the self-healing energetic composite material (sample 1).

[0052] Example 2

[0053] This embodiment provides a self-healing energetic composite material (sample 2), the preparation method of which is similar to that of Example 1, the difference being the polymer T. g With the temperature set to -20℃, the monomers added to anionic copolymer emulsion A were 0.51g acrylic acid, 0.69g hydroxyethyl acrylate, 3g butyl acrylate, 21.8g isooctyl acrylate, and 0g methyl methacrylate; the monomers added to cationic copolymer emulsion B were 0.45g acrylamide, 0.47g dimethylaminoethyl acrylate, 23.6g isooctyl acrylate, 1.64g butyl acrylate, and 0g methyl methacrylate.

[0054] Example 3

[0055] This embodiment provides a self-healing energetic composite material (sample 3), the preparation method of which is similar to that of Example 1, except that the polymer Tg is set to -10℃, and the monomer addition mass of anionic copolymer emulsion A is 0.61g acrylic acid, 0.83g hydroxyethyl acrylate, 6.83g butyl acrylate, 15.7g isooctyl acrylate, and 1.85g methyl methacrylate; the monomer addition mass of cationic copolymer emulsion B is 1.83g acrylamide, 0.54g dimethylaminoethyl acrylate, 21g isooctyl acrylate, 1.95g butyl acrylate, and 1.9g methyl methacrylate.

[0056] Example 4

[0057] This embodiment provides a self-healing energetic composite material (sample 4), whose preparation method is similar to that of Example 1, the difference being the polymer T. g With the temperature set at 10℃, the monomers added to anionic copolymer emulsion A were 0.6g acrylic acid, 0.96g hydroxyethyl acrylate, 10.6g butyl acrylate, 7.59g isooctyl acrylate, and 6.18g methyl methacrylate, respectively; while the monomers added to cationic copolymer emulsion B were 0.62g acrylamide, 0.62g dimethylaminoethyl acrylate, 8g isooctyl acrylate, 11.1g butyl acrylate, and 5.56g methyl methacrylate, respectively.

[0058] Example 5

[0059] This embodiment provides a self-healing energetic composite material (sample 5), the preparation method of which is similar to that of Example 1, the difference being the polymer T. g With the temperature set at 20℃, the monomers added to anionic copolymer emulsion A were 0.72g acrylic acid, 1.16g hydroxyethyl acrylate, 6.42g butyl acrylate, 9.22g isooctyl acrylate, and 8.52g methyl methacrylate, respectively; while the monomers added to cationic copolymer emulsion B were 0.75g acrylamide, 0.76g dimethylaminoethyl acrylate, 9.73g isooctyl acrylate, 6.77g butyl acrylate, and 12.1g methyl methacrylate, respectively.

[0060] Example 6

[0061] This embodiment provides a self-healing energetic composite material (sample 6), the preparation method of which is similar to that of Example 1, except that the amount of 2-azidoethyl methacrylate added is 0g, which is 0wt% of the monomer. The monomers added in anionic copolymer emulsion A are 1.09g acrylic acid, 1.75g ​​hydroxyethyl acrylate, 9.87g butyl acrylate, 13.9g isooctyl acrylate, and 11.3g methyl methacrylate, respectively; the monomers added in cationic copolymer emulsion B are 0.96g acrylamide, 0.96g dimethylaminoethyl acrylate, 14.9g isooctyl acrylate, 10.4g butyl acrylate, and 11g methyl methacrylate, respectively.

[0062] Example 7

[0063] This embodiment provides a self-healing energetic composite material (sample 7), the preparation method of which is similar to that of Example 1, except that the amount of 2-ethyl methacrylate-2-azidoacrylate added is 8g, which is 20wt% of the monomer. The monomers added in anionic copolymer emulsion A are 0.91g acrylic acid, 1.47g hydroxyethyl acrylate, 9.76g butyl acrylate, 11.7g isooctyl acrylate, and 6.1g methyl methacrylate, respectively; the monomers added in cationic copolymer emulsion B are 0.82g acrylamide, 0.82g dimethylaminoethyl acrylate, 13.8g isooctyl acrylate, 8.84g butyl acrylate, and 5.76g methyl methacrylate, respectively.

[0064] Example 8

[0065] This embodiment provides a self-healing energetic composite material (sample 8), the preparation method of which is similar to that of Example 1, except that the amount of 2-azidoethyl methacrylate added is 16g, which is 40wt% of the monomer. The monomers added in anionic copolymer emulsion A are 0.53g acrylic acid, 0.85g hydroxyethyl acrylate, 5.64g butyl acrylate, 13.5g isooctyl acrylate, and 1.47g methyl methacrylate; the monomers added in cationic copolymer emulsion B are 0.53g acrylamide, 0.53g dimethylaminoethyl acrylate, 13.7g isooctyl acrylate, 5.7g butyl acrylate, and 1.48g methyl methacrylate.

[0066] Example 9

[0067] This embodiment provides a self-healing energetic composite material (sample 9), the preparation method of which is similar to that of Example 1, except that the amount of 2-ethyl methacrylate-2-azidoacrylate added is 20g, which is 50wt% of the monomer. The monomers added in anionic copolymer emulsion A are 0.34g acrylic acid, 0.54g hydroxyethyl acrylate, 0g butyl acrylate, 17.2g isooctyl acrylate, and 0g methyl methacrylate, respectively; the monomers added in cationic copolymer emulsion B are 0.35g acrylamide, 0.35g dimethylaminoethyl acrylate, 17.9g isooctyl acrylate, 0g butyl acrylate, and 0g methyl methacrylate, respectively.

[0068] Example 10

[0069] This embodiment provides a self-healing energetic composite material (sample 10), which is prepared in a similar manner to Example 1, except that the amount of crosslinking agent 4,4'-diaminodiphenyl disulfide (C) added is 0g (molar ratio of crosslinking agent amine group to polymer epoxy group is 0:1).

[0070] Example 11

[0071] This embodiment provides a self-healing energetic composite material (sample 11), which is prepared in a similar manner to Example 1, except that the amount of crosslinking agent 4,4'-diaminodiphenyl disulfide (C) added is 0.08g (molar ratio of crosslinking agent amine group to polymer epoxy group is 0.3:1).

[0072] Example 12

[0073] This embodiment provides a self-healing energetic composite material (sample 12), which is prepared in a similar manner to Example 1, except that the amount of crosslinking agent 4,4'-diaminodiphenyl disulfide (C) added is 0.13g (molar ratio of crosslinking agent amine group to polymer epoxy group is 0.5:1).

[0074] Example 13

[0075] This embodiment provides a self-healing energetic composite material (sample 13), which is prepared in a similar manner to Example 1, except that the amount of crosslinking agent 4,4'-diaminodiphenyl disulfide (C) added is 0.21g (molar ratio of crosslinking agent amine group to polymer epoxy group is 0.8:1).

[0076] Example 14

[0077] This embodiment provides a self-healing energetic composite material (sample 14), which is prepared in a similar manner to Example 1, except that the crosslinking agent is 2,2'-diaminodiphenyl disulfide (D), and the molar ratio of the crosslinking agent amine group to the polymer epoxy group is 1:1.

[0078] Example 15

[0079] This embodiment provides a self-healing energetic composite material (sample 15), which is prepared in a similar manner to Example 1, except that the crosslinking agent is 3,3'-dithiodialanine (E), and the molar ratio of the crosslinking agent amine group to the polymer epoxy group is 1:1.

[0080] Example 16

[0081] This embodiment provides a self-healing energetic composite material (sample 16), the preparation method of which is similar to that of Example 1, except that the energetic monomer is 2-methylazidomethacrylate (AzPMEA).

[0082] Example 17

[0083] This embodiment provides a self-healing energetic composite material (sample 17), which is prepared in a similar manner to Example 1, except that the energetic monomer is 3-azido-2,2-bis(azidomethyl)propyl methacrylate (3AzEMEA).

[0084] Example 18

[0085] This embodiment provides a self-healing energetic composite material (sample 18), the preparation method of which is similar to that of Example 1, except that the energetic monomer is azide acrylate (AzEACE).

[0086] Example 19

[0087] This embodiment provides a self-healing energetic composite material (sample 19), the preparation method of which is similar to that of Example 1, except that the energetic monomer is methyl azidoacrylate (AzPACE).

[0088] Example 20

[0089] In the above embodiment, the mass ratio of energetic crystal to binder (calculated as polymer) is 4:1. In order to explore the effect of different energetic crystal to binder mass ratios on the self-healing performance of PBX, the energetic crystal to binder mass ratios were adjusted to 1:1 and 20:1 respectively based on Example 1. The energetic crystal was coated and PBX samples were prepared, which were named Sample 20 and Sample 21 respectively.

[0090]

[0091] As can be seen from the above examples, Example 4 had an excessively high glass transition temperature, resulting in overly rigid polymer chains and a long healing time; Example 5 had an excessively high glass transition temperature, resulting in overly rigid polymer chains, poor self-healing performance, and inability to repair; Example 9 had an excessively high proportion of energetic monomers, with a large proportion of rigid segments and a small proportion of flexible segments, making the emulsion unstable during polymerization and unable to coat the energetic crystals; Example 10 did not use a crosslinking agent, making it impossible to construct a self-healing network interwoven with disulfide bonds and ionic bonds; the emulsion polymerization in samples 18 and 19 was unstable because the monomers ethyl 2-azidoacrylate (AzEACE) and isopropyl 1-azidoacrylate (AzPACE) were unstable, easily ignited, and dangerous. Sample 21 had poor self-healing performance due to its low binder content, and was almost impossible to repair.

[0092] The energetic composite material synthesized using this patent exhibits excellent self-healing properties. Its self-healing after the formation of microcracks extends the material's service life, and it also demonstrates superior and stable mechanical properties. In comparison, Sample 1 possesses both good mechanical properties and good self-healing performance, providing guidance for the current development of green synthetic self-healing energetic adhesives.

Claims

1. A method for preparing a self-healing energetic adhesive, characterized in that, Includes the following steps: (1) Preparation of anionic copolymer emulsion: A mixture of monomers containing energetic monomers, anionic monomers, hydrophilic monomers and lipophilic monomers is subjected to free radical emulsion polymerization in water in the presence of emulsifier, initiator and chain transfer agent to obtain a stable anionic copolymer emulsion; (2) Preparation of cationic copolymer emulsion: A mixture of monomers containing energetic monomers, cationic monomers, hydrophilic monomers and lipophilic monomers is subjected to free radical emulsion polymerization in water in the presence of emulsifiers, initiators and chain transfer agents to obtain a stable cationic copolymer emulsion; (3) Preparation of composite material: The anionic copolymer emulsion obtained in step (1) is mixed with the energetic crystal, and then the crosslinking agent and the cationic copolymer emulsion obtained in step (2) are added. The mixture is stirred to break the emulsion and coat the energetic crystal. After filtration, drying, pressing and molding and room temperature curing, a self-healing energetic adhesive is obtained. The energetic monomer is selected from at least one of the azidoacrylate monomers; The azidoacrylate monomers are selected from 2-azidoethyl methacrylate and 3-azido-2,2-bis(azidomethyl)propyl methacrylate, and the hydrophilic monomers are selected from at least one of hydroxyethyl acrylate and acrylamide; The lipophilic monomer is selected from at least one of butyl acrylate, isooctyl acrylate, methyl methacrylate, styrene, and glycidyl methacrylate, and the crosslinking agent is an amine or acid compound containing a disulfide bond; In the adhesive, the energetic monomer accounts for 10% to 40% of the total monomer mass; the glass transition temperature of the copolymer is -20°C to 10°C. The ratio of energetic crystal to polymer is 1:1 to 9:

1.

2. The method for preparing the self-healing energetic adhesive according to claim 1, characterized in that, The anionic copolymer emulsion contains ionic monomers selected from at least one of acrylic acid, methacrylic acid, and their sodium or potassium salts; the cationic copolymer emulsion contains ionic monomers selected from at least one of dimethylaminoethyl acrylate and dimethylaminoethyl methacrylate quaternary ammonium salt.

3. The method for preparing the self-healing energetic adhesive according to claim 1, characterized in that, The amine or acid compounds containing disulfide bonds are selected from any one of 4,4'-diaminodiphenyl disulfide, 2,2'-diaminodiphenyl disulfide, 3,3'-dithiodialanine, and 2,2'-dithiodiethylamine dihydrochloride.

4. The method for preparing the self-healing energetic adhesive according to claim 1, characterized in that, In steps (1) and (2), the initiator is a persulfate and / or an azo initiator, the chain transfer agent is a thiol compound, and the emulsifier is a compound system of nonionic and ionic emulsifiers.

5. The method for preparing the self-healing energetic adhesive according to claim 1, characterized in that, In step (3), the amount of crosslinking agent added is such that the molar amount of functional groups in the crosslinking agent that can react with the reactive groups in the polymer accounts for 10% to 100% of the total molar amount of the corresponding reactive groups in the polymer.

6. The application of a self-healing energetic adhesive prepared by the method of any one of claims 1-5 in the preparation of polymer-bonded explosives (PBX).

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