A perfluorohexanone microcapsule composite filling glue, a preparation method and application thereof

Abstract

This invention discloses a perfluorohexanone microcapsule composite filler, its preparation method, and its application. The raw materials for the perfluorohexanone microcapsule composite filler include the following components: 10-40 parts perfluorohexanone microcapsules, 50-80 parts modified elastomer matrix, 2-8 parts plasticizer, 1-5 parts flame retardant synergist, 0.5-3 parts coupling agent, and 0.1-1 parts defoamer. The modified elastomer matrix comprises a hybrid network structure formed by chemical crosslinking or grafting of an organosilicon polymer and an elastomer prepolymer, ensuring that the material maintains hydrophobicity under long-term storage and complex working conditions, and integrates intelligent fire extinguishing, efficient synergistic shock absorption, and durable waterproofing and dustproofing.

Description

Technical Field

[0001] This invention relates to the field of fire protection materials and new energy safety protection technology, and in particular to a perfluorohexanone microcapsule composite filler, its preparation method and application. Background Technology

[0002] With the widespread application of lithium batteries in consumer electronics (such as power banks) and electric vehicles, their service environments are becoming increasingly complex, facing dual safety threats of "internal thermal runaway" and "external environmental corrosion." On the one hand, lithium battery thermal runaway can easily lead to fire or even explosion. Traditional fire extinguishing media (such as dry powder and gas) are limited by their physical form and cannot penetrate into the micron-sized gaps between battery electrodes and winding layers, making early and precise suppression impossible. Furthermore, they lack mechanical shock absorption capabilities and are ill-suited to handle vibrations and shocks during equipment operation. On the other hand, in outdoor, high-humidity, or dusty environments, the intrusion of moisture and dust can easily lead to internal circuit short circuits and cell corrosion, significantly reducing the thermal stability of the battery system and further exacerbating the risk of thermal runaway. Therefore, single-dimensional protection measures are no longer sufficient to meet the safety requirements under complex operating conditions.

[0003] To address the aforementioned issues, existing protection solutions suffer from significant functional gaps and technical shortcomings. While ordinary silicone and other potting materials possess certain shock absorption, cushioning, and sealing properties, they lack active fire extinguishing capabilities and cannot interrupt the combustion chain reaction. Highly efficient fire extinguishing agents such as perfluorohexanone, if used directly in liquid or simple atomized form, suffer from problems such as easy leakage and difficulty in retention, making it impossible to effectively persist in the confined space inside a battery for an extended period. Although microencapsulation technology theoretically achieves controlled release and long-term retention of fire extinguishing agents through polymer wall material encapsulation, current technologies have yielded unsatisfactory results: firstly, microcapsules themselves suffer from low encapsulation rates and poor temperature resistance of the wall materials; secondly, the interfacial compatibility between microcapsules and the elastomer matrix is ​​insufficient, leading to agglomeration at high filling volumes, resulting in a sharp increase in the viscosity of the composite compound, reduced fluidity, and difficulty in injection construction; thirdly, microcapsules often act as stress concentration points in the matrix, failing to enhance damping and energy absorption characteristics and instead weakening the overall mechanical properties of the material, and current research generally neglects the development of the material's intrinsic hydrophobic protective function.

[0004] Therefore, developing a composite filler adhesive that combines high fluidity, efficient fire extinguishing, synergistic shock absorption, and waterproof and dustproof properties is of great significance for improving the safety protection level of lithium batteries and power banks in complex environments. Summary of the Invention

[0005] The main objective of this invention is to propose a perfluorohexanone microcapsule composite filler, its preparation method, and its application, aiming to solve the problem that existing technologies cannot simultaneously achieve high-efficiency fire extinguishing, synergistic shock absorption, and waterproof and dustproof performance.

[0006] To achieve the above objectives, the present invention provides a perfluorohexanone microcapsule composite filler. By weight, the raw materials of the perfluorohexanone microcapsule composite filler include the following components: 10-40 parts perfluorohexanone microcapsules, 50-80 parts modified elastomer matrix, 2-8 parts plasticizer, 1-5 parts flame retardant synergist, 0.5-3 parts coupling agent, and 0.1-1 parts defoamer. The modified elastomer matrix comprises a hybrid network structure formed by chemical crosslinking or grafting of an organosilicon polymer and an elastomer prepolymer.

[0007] In one embodiment, the organosilicon polymer comprises one or more of amino-terminated polysiloxanes, hydroxyl-terminated polysiloxanes, epoxy-terminated polysiloxanes, vinyl-terminated polysiloxanes, and mercapto-terminated polysiloxanes; and / or, The elastomer prepolymer includes at least one of isocyanate-terminated polyurethane prepolymer, anhydride-terminated polyurethane prepolymer, epoxy-terminated polyurethane prepolymer, carboxyl-terminated polyurethane prepolymer, polyurea prepolymer, and acrylate prepolymer; and / or, The hybrid network structure includes semi-interpenetrating networks, fully interpenetrating networks, or chemically grafted copolymer networks.

[0008] In one embodiment, the plasticizer comprises at least one of dibutyl phthalate, dioctyl sebacate, and epoxidized soybean oil; and / or, The flame retardant synergist includes at least one of aluminum hydroxide, magnesium hydroxide, and ammonium polyphosphate; and / or, The coupling agent includes KH550 or KH560; and / or, The defoaming agent includes silicone-based agents.

[0009] In one embodiment, the preparation method of the perfluorohexanone microcapsule composite filler includes the following steps: S10. Place the organosilicon polymer in a vacuum oven and dehydrate it under vacuum to obtain a pretreated organosilicon polymer. S20. The pretreated organosilicon polymer is mixed with the elastomer prepolymer and aged at a constant temperature to obtain a mixture; S30. The mixture is post-processed, cooled and discharged to obtain the modified elastomer matrix.

[0010] S40. The modified elastomer matrix is ​​heated and melted, and plasticizer, flame retardant synergist and coupling agent are added in sequence and stirred evenly. Then perfluorohexanone microcapsules are added and dispersed. Finally, defoamer is added and vacuum defoaming is performed to obtain perfluorohexanone microcapsule composite filler.

[0011] In one embodiment, in step S10: The viscosity of the amino-terminated polysiloxane is 1000-5000 mPa·s; and / or, The conditions for vacuum dehydration include: vacuum dehydration at 80-90℃ for 1-3 hours.

[0012] In one embodiment, in step S20, the mass ratio of the organosilicon polymer to the elastomer prepolymer is (3~12):10.

[0013] In one embodiment, in step S40: The dispersion conditions include dispersion at 2000-5000 rpm for 10-30 min; and / or, The vacuum degassing conditions include degassing for 10-20 minutes at a vacuum of -0.08 to -0.1 MPa.

[0014] This invention provides a perfluorohexanone microcapsule composite filler, wherein the perfluorohexanone microcapsule composite filler includes the perfluorohexanone microcapsule composite filler as described above or the perfluorohexanone microcapsule composite filler prepared by any of the above methods.

[0015] This invention provides an application of the perfluorohexanone microcapsule composite filler prepared by any of the above methods.

[0016] In the technical solution of this invention, the perfluorohexanone microcapsule composite filler prepared within the above-mentioned mass range, firstly in terms of shock absorption, the dispersed microcapsules, acting as "micro-elastic units," deform first to disperse local stress, and cooperate with the hybrid network matrix formed by the complementary combination of flexible organosilicon segments and rigid polyurethane structures. Furthermore, the coupling agent and chemical grafting structure greatly enhance the interfacial bonding force, preventing interfacial delamination under impact, thus upgrading the buffering effect from "simple superposition" to "continuous synergy," significantly improving vibration fatigue resistance. Secondly, in terms of protection, relying on the intrinsic low surface energy of organosilicon and… The hydrophobic groups of the coupling agent endow the material with a water contact angle of ≥90°. Combined with the excellent flowability and defect-free curing achieved by the plasticizer and defoamer, the colloid can densely penetrate into the micron-sized gaps of the battery, forming a continuous, pinhole-free hydrophobic barrier to prevent water and dust intrusion. In addition, the chemical cross-linking / grafting hybrid network structure fundamentally avoids the phase separation and additive migration that are prone to occur in traditional physical blending, ensuring that the material maintains hydrophobicity, dense integrity and high volume resistivity under long-term storage and complex working conditions. Thus, it integrates intelligent fire extinguishing, efficient synergistic shock absorption and durable waterproof and dustproof properties. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially. Furthermore, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, or solution B, or a solution where both A and B are satisfied simultaneously. In addition, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Existing protection solutions suffer from significant functional gaps and technical shortcomings. While ordinary silicone and other potting materials possess certain shock absorption and sealing properties, they lack active fire extinguishing capabilities and cannot interrupt the combustion chain reaction. Highly efficient fire extinguishing agents such as perfluorohexanone, if used directly in liquid or simple atomized form, are prone to leakage and have difficulty remaining in place, failing to effectively persist in the confined space inside the battery for extended periods. Although microencapsulation technology theoretically achieves controlled release and long-term retention of fire extinguishing agents through polymer wall material encapsulation, current applications have yielded unsatisfactory results: firstly, microcapsules themselves suffer from low encapsulation rates and poor temperature resistance of the wall materials; secondly, the interfacial compatibility between microcapsules and the elastomer matrix is ​​insufficient, leading to agglomeration at high filling volumes, resulting in a sharp increase in the viscosity of the composite compound, reduced fluidity, and difficulty in injection construction; thirdly, microcapsules often act as stress concentration points within the matrix, failing to enhance damping and energy absorption characteristics and instead weakening the overall mechanical properties of the material. Furthermore, current research generally neglects the development of the material's intrinsic hydrophobic protective function.

[0019] Therefore, developing a composite filler adhesive that combines high fluidity, efficient fire extinguishing, synergistic shock absorption, and waterproof and dustproof properties is of great significance for improving the safety protection level of lithium batteries and power banks in complex environments.

[0020] In view of this, the present invention provides a perfluorohexanone microcapsule composite filler, wherein the raw materials of the perfluorohexanone microcapsule composite filler, by weight, include the following components: 10-40 parts of perfluorohexanone microcapsules, 50-80 parts of modified elastomer matrix, 2-8 parts of plasticizer, 1-5 parts of flame retardant synergist, 0.5-3 parts of coupling agent, and 0.1-1 parts of defoamer, wherein the modified elastomer matrix comprises a hybrid network structure formed by chemical crosslinking or grafting of organosilicon polymer and elastomer prepolymer.

[0021] In the technical solution of this invention, the perfluorohexanone microcapsule composite filler prepared within the above-mentioned mass range firstly demonstrates superior shock absorption. The dispersed perfluorohexanone microcapsules, acting as "micro-elastic units," deform first to disperse local stress. This, combined with a hybrid network matrix formed by the complementary interaction of flexible silicone segments and rigid polyurethane structures, and aided by coupling agents and chemical grafting structures, significantly enhances interfacial bonding, preventing interfacial delamination under impact. This upgrades the buffering effect from "simple superposition" to "continuous synergy," significantly improving vibration fatigue resistance. Secondly, in terms of protection, relying on the intrinsic low surface area of ​​silicone… The surface energy and the hydrophobic groups of the coupling agent give the material a water contact angle of ≥90°. Combined with the excellent flowability and defect-free curing achieved by the plasticizer and defoamer, the colloid can densely penetrate into the micron-level narrow gaps of the battery, forming a continuous, pinhole-free hydrophobic barrier to prevent water and dust intrusion. In addition, the chemical cross-linking / grafting hybrid network structure fundamentally avoids the phase separation and additive migration that are prone to occur in traditional physical blending, ensuring that the material maintains hydrophobicity, dense integrity and high volume resistivity under long-term storage and complex working conditions. Thus, it integrates intelligent fire extinguishing, efficient synergistic shock absorption and durable waterproof and dustproof properties.

[0022] In the technical solution of this invention, the organosilicon polymer includes one or more of amino-terminated polysiloxanes, hydroxyl-terminated polysiloxanes, epoxy-terminated polysiloxanes, vinyl-terminated polysiloxanes, and mercapto-terminated polysiloxanes. These different end groups provide abundant chemically reactive sites, and different end groups can undergo specific chemical reactions with elastomer prepolymers or silane coupling agents (such as the reaction of amino groups with isocyanates, epoxy ring-opening polymerization, and vinyl / mercapto group participation in addition reactions). This is the key to achieving "chemical grafting" or "interpenetrating networks" and avoids phase separation caused by simple physical blending.

[0023] In the technical solution of the present invention, the elastomer prepolymer includes at least one of isocyanate-terminated polyurethane prepolymer, anhydride-terminated polyurethane prepolymer, epoxy-terminated polyurethane prepolymer, carboxyl-terminated polyurethane prepolymer, polyurea prepolymer, and acrylate prepolymer. These prepolymers contain highly active functional groups that can form chemical bonds with the end groups or coupling agents of the aforementioned organosilicones. For example, isocyanate-terminated prepolymers can directly react with amino / hydroxyl-terminated organosilicones to generate urea bonds or urethane bonds, directly constructing an "organosilicon-polyurethane" chemical grafting network at the molecular level, ensuring high-strength bonding at the interface between the two phases, and achieving a highly efficient damping effect.

[0024] In the technical solution of the present invention, the hybrid network structure includes a semi-interpenetrating network, a fully interpenetrating network, or a chemically grafted copolymer network. Chemical grafting ensures zero defects at the interface and prevents microcapsules from falling off. The interpenetrating network (IPN) utilizes the physical entanglement of two polymer chains to further restrict chain segment movement, significantly improve the damping coefficient (energy absorption capacity) and tear resistance, and can also prevent phase separation during long-term use, thus ensuring the long-term effectiveness of waterproof and shock-absorbing performance.

[0025] In the technical solution of the present invention, the plasticizer includes at least one of dibutyl phthalate, dioctyl sebacate, and epoxidized soybean oil; it adjusts the viscosity of the system and improves processing fluidity.

[0026] In the technical solution of this invention, the flame retardant synergist includes at least one of aluminum hydroxide, magnesium hydroxide, and ammonium polyphosphate; it constructs multiple flame retardant defenses and forms a "gas phase + condensed phase" synergistic flame retardant with perfluorohexanone. In the technical solution of this invention, the coupling agent includes one end reacting with the microcapsule wall material or filler, and the other end reacting with the elastomer matrix, which completely solves the interfacial compatibility problem, prevents the microcapsules from being pulled out or falling off the matrix under impact, and ensures the effective operation of the "graded buffering" mechanism.

[0027] In the technical solution of the present invention, the defoamer includes organosilicon-based agents. The above-mentioned defoamer is used to eliminate internal micropores and pinholes after curing, block the physical penetration channels of moisture and dust, and ensure the continuity and integrity of the protective layer.

[0028] In the technical solution of the present invention, the preparation method of the perfluorohexanone microcapsule composite filler includes the following steps: S10. Place the organosilicon polymer in a vacuum oven and dehydrate it under vacuum to obtain a pretreated organosilicon polymer. S20. The pretreated organosilicon polymer is mixed with the elastomer prepolymer and aged at a constant temperature to obtain a mixture; S30. The mixture is post-processed, cooled and discharged to obtain the modified elastomer matrix.

[0029] S40. The modified elastomer matrix is ​​heated and melted, and plasticizer, flame retardant synergist and coupling agent are added in sequence and stirred evenly. Then perfluorohexanone microcapsules are added and dispersed. Finally, defoamer is added and vacuum defoaming is performed to obtain perfluorohexanone microcapsule composite filler.

[0030] In the technical solution of this invention, a step-by-step process is adopted. Heating melts the modified elastomer matrix to reduce viscosity and provide a medium for the uniform dispersion of fillers. Then, with the synergy of additives, a perfluorohexanone microcapsule composite filler is finally formed, which integrates intelligent fire extinguishing, graded shock absorption and dense waterproofing.

[0031] Further, in step S10, the organosilicon polymer is placed in a vacuum oven for vacuum dehydration to ensure that the organosilicon is in an "anhydrous active state," clearing the way for the precise chemical grafting reaction with the polyurethane prepolymer in the next step and ensuring the density of the matrix structure. In step S20, the pretreated organosilicon polymer is mixed with the elastomer prepolymer. Under heat preservation conditions, the active end groups of the organosilicon (such as amino, hydroxyl, epoxy, etc.) and the end groups of the elastomer prepolymer (mainly isocyanate groups -NCO, or epoxy groups, anhydrides, etc.) undergo a stepwise polymerization reaction. As the reaction proceeds, linear organosilicon segments are chemically "grafted" onto the polyurethane backbone, or the two interpenetrate to form a semi-interpenetrating / fully interpenetrating network (IPN). The organosilicon provides flexibility and hydrophobicity, while the polyurethane provides strength and toughness. The chemical bonding ensures that the two phases do not separate, forming a modified elastomer matrix precursor with excellent damping properties. In step S30, subsequent post-processing is performed to obtain the modified elastomer matrix.

[0032] Specifically, the post-processing steps include: removing unreacted monomers using a filtration operation.

[0033] In the technical solution of the present invention, in step S10: The viscosity of the amino-terminated polysiloxane is 1000-5000 mPa·s; and / or, The conditions for vacuum dehydration include: vacuum dehydration at 80-90℃ for 1-3 hours.

[0034] In the technical solution of this invention, in step S20, the mass ratio of the organosilicon polymer to the elastomer prepolymer is (3~12):10. If the content of the organosilicon polymer is too high, it will disrupt the grafting or polymerization reaction of the elastomer prepolymer, causing the material to lose its skeletal support. If the content is too low, the lubrication and energy dissipation effects of the flexible long chains of the organosilicon polymer will be lacking, reducing the shock absorption effect.

[0035] In the technical solution of the present invention, in step S40: the dispersion conditions include dispersion at 2000-5000 rpm for 10-30 min; and / or, the vacuum degassing conditions include degassing at a vacuum of -0.08~-0.1 MPa for 10-20 min.

[0036] This is because when adding perfluorohexanone microcapsules, shear force and temperature need to be controlled to avoid damaging the microcapsule wall material. The microcapsules, as independent "fire extinguishing agent reservoirs," are uniformly suspended in the matrix without undergoing chemical reactions, thus maintaining their integrity.

[0037] The present invention also provides the aforementioned perfluorohexanone microcapsule composite filler, wherein the perfluorohexanone microcapsule composite filler includes all the beneficial effects of the perfluorohexanone microcapsule composite filler and the preparation method of the perfluorohexanone microcapsule composite filler, which will not be elaborated here.

[0038] This invention also provides an application of the perfluorohexanone microcapsule composite filler as described above. Specifically, the applications of the perfluorohexanone microcapsule composite filler include: consumer electronics: mobile phones, tablets, laptops, smartwatches, smart bands, TWS earphones, digital cameras, game consoles, and power banks; new energy transportation: pure electric vehicles, hybrid vehicles, electric two-wheelers, three-wheelers, electric buses, logistics vehicles, forklifts, electric ships, drones, and electric aircraft; energy storage: grid side: frequency regulation, peak shaving, and energy storage supporting new energy (photovoltaic / wind power); industrial and commercial: backup power supplies and peak shaving; residential energy storage: home photovoltaic energy storage systems; industrial and special equipment: industrial robots and AGVs; medical equipment: ventilators, monitors, and portable ultrasound; military and aerospace: satellites, missiles, portable communication equipment, exploration equipment, emergency power supplies, and UPS uninterruptible power supplies; lightweight portable tools; power tools: electric drills, angle grinders, and chainsaws; and garden tools: lawnmowers and hair dryers. Robotic vacuum cleaner, floor scrubber, vacuum cleaner.

[0039] Furthermore, in the technical solution of the present invention, the perfluorohexanone microcapsule composite filler is used to fill the gaps between lithium battery electrodes, with the filling volume accounting for 80%-95% of the total volume of the electrode gaps. Within the above range, by vacuum infusion or pressure injection (filling amount 80%-95%), the filler can penetrate into the gaps between lithium battery electrodes (≤0.1mm) and the narrow space between the power bank shell and the battery cell, forming a continuous, non-porous protective layer that both prevents water splashing intrusion (waterproof) and avoids the accumulation of harmful dust (dustproof). Water cannot spread and penetrate due to the formation of water droplets by the hydrophobic layer, and dust particles cannot enter the device through pores due to the dense structure.

[0040] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0041] Example 1 A perfluorohexanone microcapsule composite filler, wherein the raw materials of the perfluorohexanone microcapsule composite filler include the following components: 25 parts of perfluorohexanone microcapsules (Jiaxing Jifuai Fire Protection Technology Co., Ltd., specification: gfi microcapsule 114-000); 5 parts of plasticizer (dibutyl phthalate); 3 parts of flame retardant synergist (nano aluminum hydroxide); 1.5 parts of coupling agent (silane coupling agent KH560, i.e., γ-glycidyl etheroxypropyltrimethoxysilane); and 0.5 parts of defoamer (BYK-028). The modified elastomer matrix is ​​formed by the reaction of amino-terminated polysiloxane and isocyanate-terminated polyurethane prepolymer, wherein the amino-terminated polysiloxane (viscosity 10,000) is... mPa·s, amino content 0.8%): 32.5 parts; the isocyanate-terminated polyurethane prepolymer (prepared by reacting polyether polyol with diphenylmethane diisocyanate, NCO content 3.5%, Shore A hardness 45): 32.5 parts.

[0042] A method for preparing a perfluorohexanone microcapsule composite filler includes the following steps: Step S10: Place the above-mentioned mass of amino-terminated polysiloxane in a vacuum oven and dehydrate it under vacuum at 120°C and -0.095MPa for 2 hours until the moisture content is less than 0.05%, to obtain the pretreated active organosilicon polymer.

[0043] Step S20: The pretreated active organosilicon polymer and isocyanate-terminated polyurethane prepolymer are added to the reactor at a mass ratio of 1:1, and silane coupling agent KH560 (1.2 parts) is added at the same time. Under nitrogen protection, the temperature is raised to 100°C and the mixture is mechanically stirred at 200 rpm for 3 hours to obtain a mixture.

[0044] Step S30: After the reaction is complete, the mixture is cooled to 60°C, and then the material is filtered through a 200-mesh filter to remove gel particles. After cooling to room temperature, the material is discharged to obtain the modified elastomer matrix.

[0045] Step S40: Reheat the modified elastomer matrix to 60°C to melt and flow it. Add the plasticizer, flame retardant synergist, and the remaining silane coupling agent KH560 (0.3 parts) in sequence. Disperse at 1500 rpm for 10 minutes to fully modify the surface of the inorganic filler. Then, reduce the stirring speed to 800 rpm and slowly add the perfluorohexanone microcapsules. Continue to disperse for 15 minutes. Add the defoamer and transfer the system to a vacuum planetary mixer. Defoam at -0.09 MPa vacuum for 15 minutes until no bubbles are observed to overflow, and obtain the perfluorohexanone microcapsule composite filler product.

[0046] Example 2: Unlike Example 1, the perfluorohexanone microcapsule composite filler in Example 2 has a different mass fraction, as follows: 10 parts perfluorohexanone microcapsules; 2 parts plasticizer; 1 part flame retardant synergist; 0.5 parts coupling agent; 0.1 parts defoamer. The modified elastomer matrix is ​​formed by reacting amino-terminated polysiloxane and isocyanate-terminated polyurethane prepolymer, with 25 parts amino-terminated polysiloxane and 25 parts isocyanate-terminated polyurethane prepolymer. The rest is similar to that in Example 1.

[0047] Example 3: Unlike Example 1, the perfluorohexanone microcapsule composite filler in Example 3 has a different mass fraction, as follows: 40 parts perfluorohexanone microcapsules; 8 parts plasticizer; 5 parts flame retardant synergist; 3 parts coupling agent; and 1 part defoamer. The modified elastomer matrix is ​​formed by reacting amino-terminated polysiloxane and isocyanate-terminated polyurethane prepolymer, with 40 parts amino-terminated polysiloxane and 40 parts isocyanate-terminated polyurethane prepolymer. The rest is similar to that in Example 1.

[0048] Example 4 Unlike Example 1, the mass ratio of the organosilicon polymer to the elastomer prepolymer is 2:10, otherwise it is similar to Example 1.

[0049] Example 5 Unlike Example 1, the mass ratio of the silicone polymer to the elastomer prepolymer is 3:10, otherwise it is similar to Example 1.

[0050] Example 6 Unlike Example 1, the mass ratio of the organosilicon polymer to the elastomer prepolymer is 12:10, otherwise it is similar to Example 1.

[0051] Comparative Example 1 Unlike Example 1, the preparation of the modified elastomer matrix did not involve adding coupling agent KH560 or performing a heat preservation and curing reaction; otherwise, it was similar to Example 1.

[0052] Compared with Example 1, Examples 2-6 and Comparative Example 1 are the same as Example 1 except for the amount of each component of the perfluorohexanone microcapsule composite filler. The specific differences are shown in Table 1. The mass ratio of the organosilicon polymer to the elastomer prepolymer is denoted as m.

[0053] Table 1. Parameters of the perfluorohexanone microcapsule composite filler in Examples 1 to 6

[0054] Performance testing The perfluorohexanone microcapsule composite filler from Examples 1-6 and Comparative Example 1 was filled into the gap between the casing and the cell of a commercially available lithium-ion battery module (simulating a power bank application, with dimensions of 100×60×20mm, cell capacity of 10000mAh, and a polycarbonate casing) (filling amount 85%), and relevant tests were conducted: 1. Mechanical impact performance test Following the principles of IEC 62133-2:2017 and GB 31241-2014, an instrumented drop hammer impact test was adopted. A triaxial accelerometer was fixed at the center of the power bank cell. The drop hammer impact condition was set as a half-sine wave pulse with a peak acceleration of 50g and a duration of 11ms. The measured peak acceleration of the cell was recorded, and the energy absorption efficiency was calculated.

[0055] 2. Thermal runaway suppression and response testing The test simulates the extreme condition of thermal runaway caused by battery overcharging. A 100W ceramic heating element is used to heat the surface of the battery cell until thermal runaway is triggered. The trigger threshold is defined as when the internal ambient temperature rises to 130°C or the temperature rise rate exceeds 1°C / s. External heating is then stopped. The test results require that the open flame be completely extinguished within 10 seconds and the core temperature of the system can quickly drop and stabilize below 60°C to ensure no risk of reignition.

[0056] 3. Enclosure protection rating (IP54) verification According to GB / T 4208-2017 standard, the finished power bank after filling was tested for IP54 rating. Dustproof test (negative pressure sand and dust chamber) and splash test (multi-directional splash water) were carried out in sequence. After the test, the internal parts were disassembled and inspected and found to be free of harmful dust and moisture residue, and the charging and discharging functions were normal.

[0057] 4. Long-term environmental stability test The pre-filled power bank was placed in a constant temperature and humidity chamber at 60°C and 90% RH for 6 months (simulating a long-term harsh environment). After the sample was removed and allowed to return to room temperature, the mechanical shock test, thermal runaway test, and IP54 test were repeated to confirm that its protective performance did not suffer from functional degradation. The test results are shown in Table 2. Table 2

[0058] As shown in Table 2, the examples constructed a dense interpenetrating network structure through a high-temperature grafting reaction of amino-terminated polysiloxane and isocyanate prepolymer under the action of KH560 coupling agent. This transformed the originally incompatible organosilicon and polyurethane from a simple physical stacking into a strong chemical bond, fundamentally solving the interfacial delamination problem. This endowed the material with extremely high energy absorption efficiency (shock absorption) and long-term sealing reliability (waterproof and dustproof). Compared with Comparative Example 2, which used a conventional matrix, the examples utilized the low surface energy and excellent weather resistance provided by the long-chain organosilicon to ensure the material's high elasticity and shock absorption while providing a more stable physical barrier for the perfluorohexanone microcapsules. This prevented the extinguishing agent from penetrating and leaking during long-term storage and ensured that the matrix could rupture sensitively with the microcapsules and form an efficient agent delivery channel under thermal runaway conditions. Thus, a balance was achieved between the three performance characteristics of "high-efficiency fire extinguishing, dynamic shock absorption, and long-lasting protection".

[0059] Furthermore, experiments in Examples 4-6 revealed that when the mass ratio of silicone to polyurethane in the elastomer prepolymer is controlled within a specific range of 3:10 to 12:10, the interpenetrating polymer network formed within the system is the most dense and ordered. If the ratio is lower than this range (as in Example 4), the continuous phase is mainly occupied by rigid polyurethane, resulting in insufficient viscoelastic dissipation when the material absorbs impact energy and making it prone to stress cracking under environmental stress. Within this specific range, the long chain segments of silicone can be precisely embedded in the polyurethane skeleton, providing excellent dynamic damping displacement space and forming a dense hydrophobic barrier at the sealing interface using its low surface energy characteristics. This achieves a nonlinear synergistic improvement in mechanical toughness and environmental reliability while ensuring efficient fire extinguishing.

[0060] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A perfluorohexanone microcapsule composite filler, characterized in that, The raw materials of the perfluorohexanone microcapsule composite filler, by weight, include the following components: 10-40 parts of perfluorohexanone microcapsules, 50-80 parts of modified elastomer matrix, 2-8 parts of plasticizer, 1-5 parts of flame retardant synergist, 0.5-3 parts of coupling agent, and 0.1-1 parts of defoamer. The modified elastomer matrix comprises a hybrid network structure formed by chemical crosslinking or grafting of organosilicon polymer and elastomer prepolymer.

2. The perfluorohexanone microcapsule composite filler as described in claim 1, characterized in that, The organosilicon polymer includes one or more of amino-terminated polysiloxanes, hydroxyl-terminated polysiloxanes, epoxy-terminated polysiloxanes, vinyl-terminated polysiloxanes, and mercapto-terminated polysiloxanes; and / or, The elastomer prepolymer includes at least one of isocyanate-terminated polyurethane prepolymer, anhydride-terminated polyurethane prepolymer, epoxy-terminated polyurethane prepolymer, carboxyl-terminated polyurethane prepolymer, polyurea prepolymer, and acrylate prepolymer; and / or, The hybrid network structure includes semi-interpenetrating networks, fully interpenetrating networks, or chemically grafted copolymer networks.

3. The perfluorohexanone microcapsule composite filler as described in claim 1, characterized in that, The plasticizer includes at least one of dibutyl phthalate, dioctyl sebacate, and epoxidized soybean oil; and / or The flame retardant synergist includes at least one of aluminum hydroxide, magnesium hydroxide, and ammonium polyphosphate; and / or, The coupling agent includes KH550 or KH560; and / or, The defoaming agent includes silicone-based agents.

4. A method for preparing the perfluorohexanone microcapsule composite filler as described in any one of claims 1 to 3, characterized in that, The preparation method of the perfluorohexanone microcapsule composite filler includes the following steps: S10. Place the organosilicon polymer in a vacuum oven and dehydrate it under vacuum to obtain a pretreated organosilicon polymer. S20. The pretreated organosilicon polymer is mixed with the elastomer prepolymer and aged at a constant temperature to obtain a mixture; S30. The mixture is post-processed, cooled and discharged to obtain the modified elastomer matrix; S40. The modified elastomer matrix is ​​heated and melted, and plasticizer, flame retardant synergist and coupling agent are added in sequence and stirred evenly. Then perfluorohexanone microcapsules are added and dispersed. Finally, defoamer is added and vacuum defoaming is performed to obtain perfluorohexanone microcapsule composite filler.

5. The method for preparing the perfluorohexanone microcapsule composite filler as described in claim 4, characterized in that, In step S10: The organosilicon polymer comprises an amino-terminated polysiloxane, the viscosity of which is 1000-5000 mPa·s; and / or, The conditions for vacuum dehydration include: vacuum dehydration at 80-90℃ for 1-3 hours.

6. The method for preparing the perfluorohexanone microcapsule composite filler as described in claim 4, characterized in that, In step S20, the mass ratio of the organosilicon polymer to the elastomer prepolymer is (3~12):

10.

7. The method for preparing the perfluorohexanone microcapsule composite filler as described in claim 4, characterized in that, In step S40: The dispersion conditions include dispersion at 2000-5000 rpm for 10-30 min; and / or, The vacuum degassing conditions include degassing for 10-20 minutes at a vacuum of -0.08 to -0.1 MPa.

8. An application of the perfluorohexanone microcapsule composite filler as described in claim 7.

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