Fire-extinguishing, sealing and shock-absorbing material, preparation method, battery pack and connecting piece

Abstract

The invention discloses a preparation method of a fire-extinguishing, sealing and shock-absorbing material, and relates to the technical field of material manufacturing, the preparation method comprises the following steps: under the conditions of nitrogen protection and nitrogen flow of 0.8-1.5 L / min, reacting 50-100 parts by weight of perfluorohexanone system, 20-50 parts by weight of 6-functionality polyether polyol and 10-100 parts by weight of 3M1230 nanocapsule flame retardant at 55 + / -2 DEG C for 2 hours to obtain the fire-extinguishing, sealing and shock-absorbing material. The content of NCO in the prepolymer is 8-12%; the preparation method comprises the following steps: carrying out ultrasonic treatment on 50-100 parts by weight of polyether polyol, 5-10 parts by weight of 80-300-mesh expandable graphite and 3-8 parts by weight of nano fumed silica for 30 minutes, and adding 1-3 parts by weight of a cross-linking agent to form a polyol system; and mixing the prepolymer, the polyol system and the perfluorohexanone system according to a ratio of 1: (0.2-0.5): (0.3-0.6), carrying out casting molding at a shear rate of 1000-1500s through a six-stage static mixer, and curing to complete the preparation of the damping material.

Description

Technical Field

[0001] The present invention relates to the technical field of material manufacturing, and particularly to a fire extinguishing, sealing and shock-absorbing material, a preparation method, a battery pack and a connecting piece. Background Art

[0002] In many fields such as industry, construction, transportation and warehousing logistics, the demand for high-performance flame-retardant, sealing and shock-absorbing materials is increasing day by day. In recent years, with the rapid development of chemical technology and the continuous progress of production technology, remarkable achievements have been made in the modification research of polymer materials. By introducing functional additives such as flame retardants, sealing enhancers and shock absorbers, the flame retardant performance, sealing performance and shock absorption performance of polymer materials can be significantly improved. However, the introduction of these additives often has a certain impact on the overall performance of the material, such as reducing the mechanical strength, heat resistance, etc. of the material. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a fire extinguishing, sealing and shock-absorbing material and a preparation method to solve the above problems.

[0004] The present invention is realized through the following technical solutions: The present invention discloses a preparation method of a fire extinguishing, sealing and shock-absorbing material, including: Under the condition of nitrogen protection and a nitrogen flow rate of 0.8 - 1.5 L / min, 50 - 100 parts by weight of modified MDI, 20 - 50 parts by weight of 6-functional polyether polyol, and 10 - 100 parts by weight of 3M1230 nano-capsule flame retardant are reacted at 55 ± 2 °C for 2 hours to form a prepolymer with an NCO content of 8 - 12%; 50 - 100 parts by weight of polyether polyol, 5 - 10 parts by weight of expandable graphite with a particle size of 80 - 300 mesh, and 3 - 8 parts by weight of nano-aerosil are ultrasonicated for 30 min, and then 1 - 3 parts by weight of a cross-linking agent is added to form a polyol system; The prepolymer, the polyol system and the perfluoromethylcyclohexanone system are mixed in a ratio of 1:0.2 - 0.5:0.3 - 0.6, and are cast and molded through a 6-stage static mixer at a shear rate of 1000 - 1500 s⁻¹, and after curing, the preparation of the shock-absorbing material is completed.

[0005] Preferably, the modified MDI is carbodiimide-modified 4,4'-diphenylmethane diisocyanate, its viscosity range at 25 °C is 150 - 300 mPa・s, and the content of carbodiimide groups is 1 - 5 wt%.

[0006] Preferably, the polyether polyol is selected from one or more of types 1618, 104, 210, and 220; And / or, the specific surface area of the nano-aerosil is ≥200 m² / g; And / or, the crosslinking agent is one or more of ethylene glycol, 1,4-butanediol, diethylene glycol, dipropylene glycol; And / or, the hydroxyl value of the polyether polyol is 28 - 56 mgKOH / g, and the block distribution of propylene oxide in the molecular chain shows a gradient change.

[0007] Preferably, the cast material is cured according to a gradient curing program of maintaining at 50°C for 30 min, 80°C for 60 min, and 120°C for 90 min.

[0008] Preferably, the mass ratio of the expandable graphite to the nano-aerosil is 1:0.3 - 1:0.6, the initial expansion temperature of the expandable graphite is 180 ± 5°C, and the expansion volume is ≥250 mL / g.

[0009] Preferably, when adding 3M1230 nano-capsule flame retardant, 2 - 5 parts by weight of amino-silane modified montmorillonite is added simultaneously. The interlayer cation exchange capacity of the amino-silane modified montmorillonite is ≥100 mmol / 100 g, the particle size D50 ≤ 500 nm, the modifier is 3-aminopropyltriethoxysilane, and its addition amount accounts for 0.5 - 1.2% of the mass of montmorillonite.

[0010] Preferably, the static mixer includes at least six mixing units, each unit is composed of a 45° cross helical gear structure, and the tooth gap width is 0.2 - 0.5 mm.

[0011] A fire extinguishing, sealing and shock-absorbing material is prepared by the above preparation method.

[0012] A battery pack, characterized in that it includes a housing and electric cores arranged inside the housing, and the material of the housing is the above shock-absorbing material.

[0013] A connector, including a first flange and a second flange, the first flange and the second flange clamp a sealing gasket, and the material of the sealing gasket is the above shock-absorbing material.

[0014] The present invention discloses a preparation method of a fire extinguishing, sealing and shock-absorbing material. Compared with the prior art: In the present invention, the fire extinguishing, sealing and shock-absorbing material prepared by the above steps has excellent performance. It has high flame retardant performance, effectively prevents the spread of fire during combustion, protects the safety of personnel and property, and has good sealing performance, preventing the leakage of gas or liquid, meeting the sealing requirements in specific applications. It also has excellent shock-absorbing performance, absorbing and dispersing vibration energy, and reducing the impact of vibration on equipment and structures. Description of the Drawings

[0015] Figure 1 are the components of the material in one embodiment; Figure 2 is a micrograph of the material in one embodiment. Detailed implementation manners

[0016] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various exemplary embodiments of the present disclosure as defined by the claims and their equivalents. This description includes various details to assist in understanding, but these details will be considered merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and structures may be omitted for clarity and conciseness.

[0017] It will be understood that when an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it can be directly on, directly connected or coupled to, that other element or layer, or there may also be one or more intervening elements or layers. When an element is referred to as being "directly on," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers.

[0018] It will be understood that although terms such as first, second, third, etc. may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, without departing from the teachings of the exemplary embodiments, the first element, first component, first display region, first layer, or first section discussed below may be referred to as the second element, second component, second display region, second layer, or second section. In the drawings, for the sake of clarity, the dimensions of various elements, layers, etc. may be exaggerated.

[0019] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0020] The preparation method of the fire extinguishing, sealing and shock-absorbing material in this application document has an automatic cooking function. When the user uses it, they only need to put the ingredients into the pot and select the corresponding cooking program parameters, and the preparation method of the fire extinguishing, sealing and shock-absorbing material can process the ingredients and complete the cooking.

[0021] Please refer to Figure 1 , Figure 1 is a component of a fire extinguishing, sealing and shock-absorbing material, and its preparation method includes: Under the condition of nitrogen protection and nitrogen flow rate of 0.8-1.5L / min, 50-100 parts by weight of modified MDI, 20-50 parts by weight of 6-functionality polyether polyol, and 10-100 parts by weight of 3M1230 nano-capsule flame retardant are reacted at 55±2°C for 2 hours to form a prepolymer with an NCO content of 8-12%; 50-100 parts by weight of polyether polyol, 5-10 parts by weight of 80-300 mesh expandable graphite, and 3-8 parts by weight of nano-fumed silica are ultrasonically treated for 30 minutes, and then 1-3 parts by weight of a cross-linking agent are added to form a polyol system; The prepolymer, the polyol system and the perfluorohexanone system are mixed in a ratio of 1:0.2-0.5:0.3-0.6, and cast through a 6-stage static mixer at a shear rate of 1000-1500s⁻¹, and the preparation of the shock absorbing material is completed after curing. Figure 2 A microscopic diagram of the prepared material.

[0022] Specifically, the MDI molecule contains an isocyanate group (-NCO), and 20-50 parts by weight of a 6-functionality polyether polyol is selected. Each polyether polyol molecule contains 6 hydroxyl groups (-OH). The hydroxyl groups react with the isocyanate groups in MDI to form polyurethane segments. For the 3M1230 nano-capsule flame retardant, when the material burns, it releases flame-retardant gas or forms a heat-insulating layer, thereby effectively preventing the spread of the fire. Reacting the flame retardant with MDI and polyether polyol can directly incorporate flame retardant properties into the polyurethane material and improve its flame retardant grade. In order to ensure the smooth progress of the reaction and control the performance of the prepolymer, this step is carried out under nitrogen protection. Nitrogen, as an inert gas, effectively removes oxygen and moisture from the reaction system. The nitrogen flow rate is controlled in the range of 0.8-1.5L / min, which ensures the inert atmosphere of the reaction system without causing nitrogen waste. The reaction time is 2 hours to allow MDI and polyether polyol to fully react and form a stable prepolymer.

[0023] In the preparation of the polyol system, 50 - 100 parts by weight of polyether polyol was selected as the basic raw material. Different from the polyether polyol in the prepolymer preparation, the polyether polyol was used to mix with fillers such as expandable graphite and nano - fumed silica to form a polyol system with specific properties. Expandable graphite is a material that expands rapidly at high temperatures, forming a multi - layer graphite sheet structure, effectively blocking heat and oxygen and enhancing the flame - retardant performance of the material. In this example, 5 - 10 parts by weight of expandable graphite with a particle size of 80 - 300 mesh was added. The particle size range of 80 - 300 mesh ensures the uniform dispersion of graphite in the material and improves its flame - retardant efficiency. Nano - fumed silica is a nano - filler in the example, enhancing the mechanical properties and heat resistance of the material. At the same time, it promotes the compatibility and dispersibility between components and improves the overall performance of the material. In the example, 3 - 8 parts by weight of nano - fumed silica was added. In order to uniformly disperse expandable graphite and nano - fumed silica in the polyether polyol, an ultrasonic treatment method was adopted, so that the filler particles are subjected to strong shearing and impact in the polyether polyol, thus achieving uniform dispersion. The treatment time was 30 min, which is sufficient for the filler particles to be fully dispersed in the polyether polyol. 1 - 3 parts by weight of cross - linker was added to the polyol system. The cross - linker is a substance that promotes the chemical cross - linking reaction between polyurethane segments, enhancing the network structure and stability of the material and improving its mechanical properties and heat resistance. In the step of mixing the prepolymer, the polyol system and the perfluoropentanone system, the perfluoropentanone system is a highly reactive hardener containing a large number of isocyanate groups, which reacts with the hydroxyl groups in the prepolymer and the polyol system, accelerating the curing process of the material. The mixing ratio is carried out according to the ratio of prepolymer: polyol system: perfluoropentanone system = 1:0.2 - 0.5:0.3 - 0.6. The mixing process is completed by a 6 - stage static mixer. In this example, a shear rate of 1000 - 1500 s⁻¹ was selected for mixing. The shear rate is the magnitude of the shear force exerted on the fluid during the mixing process. The mixed material was immediately poured into a mold for molding. In the mold, the material was cured at an appropriate temperature, causing the chemical cross - linking reaction between polyurethane segments to form a stable network structure. The fire - extinguishing, sealing and shock - absorbing material prepared through the above steps has excellent properties. Among them, the preparation of the perfluoropentanone system includes using perfluoropentanone fire - extinguishing agent as the core material, adopting a composite wall material of thermoplastic resin and photosensitive polymer containing azobenzene groups, and preparing microcapsules through a fluidized - bed coating technology. The particle size of the microcapsules is 10 - 600 μm and the coefficient of uniformity of distribution ≤ 0.3; low - melting - point alloy particles (melting point 120 - 150 °C) are embedded in the wall material, and their mass accounts for 5 - 15% of the total amount of the wall material; the dispersion of the microcapsules is controlled by ultrasonic emulsification (frequency 20 kHz, power 500 W). The composite wall material contains, by weight: Thermoplastic resin (such as polylactic acid) 60 - 80 parts 15 - 30 parts of photosensitive polymer (containing azobenzene groups) 3 - 8 parts of plasticizer (such as dibutyl phthalate) The photosensitive polymer undergoes cis - trans isomerization within 3 seconds under 300 - 400 nm light radiation, and the product remains uniformly dispersed during the storage period. It has high flame - retardant performance, effectively prevents the spread of fire during combustion, protects the safety of personnel and property, and has good sealing performance, preventing the leakage of gas or liquid, meeting the sealing requirements in specific applications. It also has excellent shock - absorption performance, absorbing and dispersing vibration energy, and reducing the impact of vibration on equipment and structures.

[0024] Further, the polyether polyol is selected from one or more of types 1618, 104, 210, and 220; And / or, the specific surface area of the nano - fumed silica ≥ 200 m² / g; And / or, the cross - linker is one or more of ethylene glycol, 1,4 - butanediol, diethylene glycol, and dipropylene glycol; And / or, the hydroxyl value of the polyether polyol is 28 - 56 mgKOH / g, and the block distribution of propylene oxide in the molecular chain shows a gradient change.

[0025] In one embodiment, the cast - molded material is cured according to a gradient curing program of maintaining at 50℃ for 30 min, 80℃ for 60 min, and 120℃ for 90 min. During the curing process, it is uniformly heated to avoid generating internal stress and cracks, thereby obtaining a high - quality fire - extinguishing, sealing, and shock - absorbing material.

[0026] Further, the mass ratio of expandable graphite to nano - fumed silica is 1:0.3 - 1:0.6, the initial expansion temperature of the expandable graphite is 180 ± 5℃, and the expansion volume ≥ 250 mL / g.

[0027] In one embodiment, when adding a perfluoromethylcyclohexanone system, 2-5 parts by weight of amino-silane modified montmorillonite is added simultaneously. The interlayer cation exchange capacity of the amino-silane modified montmorillonite is ≥100 mmol / 100 g, the particle size D50 ≤ 500 nm, and the modifier is 3-aminopropyltriethoxysilane, and its addition amount accounts for 0.5-1.2% of the mass of montmorillonite. Specifically, the modifier is selected as 3-aminopropyltriethoxysilane, and its addition amount accounts for 0.5-1.2% of the mass of montmorillonite. 3-aminopropyltriethoxysilane reacts with the hydroxyl groups on the surface of montmorillonite to form chemical bonding, improving the compatibility and interfacial bonding force between montmorillonite and the polymer matrix. Through chemical modification, the dispersibility of montmorillonite in the polymer is improved, and the interaction between it and the polymer matrix is enhanced, enabling the material to better transmit stress when subjected to external forces and improving the mechanical properties of the material. The amino-silane modified montmorillonite and the 3M1230 nano-capsule flame retardant are added simultaneously, and their synergistic flame retardancy is achieved. The layered structure of montmorillonite forms a physical barrier layer during material combustion to prevent the spread of flames and the release of smoke; while the 3M1230 nano-capsule flame retardant releases flame retardant gases at high temperatures to further inhibit the combustion reaction.

[0028] In one embodiment, the static mixer includes at least six mixing units, each unit is composed of a 45° cross helical tooth structure, and the tooth gap width is 0.2-0.5 mm. The above range can not only ensure sufficient contact and mixing between raw materials, but also avoid excessive shear force generated during the mixing process of raw materials, thereby protecting the molecular structure of raw materials from being damaged. When the raw materials pass through the static mixer, they will pass through each mixing unit in turn. In each unit, the 45° cross helical tooth structure will cause the raw materials to be shunted, rotated and recombined, thus achieving sufficient mixing between the raw materials.

[0029] In one embodiment, a fire extinguishing, sealing and shock-absorbing material is disclosed, and the shock-absorbing material is prepared by the above preparation method.

[0030] In one embodiment, a battery pack is disclosed, which is characterized by including a housing and battery cells arranged inside the housing, and the material of the housing is the above shock-absorbing material.

[0031] In one embodiment, a connector is disclosed, which includes a first flange and a second flange, and the first flange and the second flange clamp a sealing gasket, and the material of the sealing gasket is the above shock-absorbing material.

[0032] In summary, the present invention provides an active fire extinguishing material based on microcapsule encapsulation technology, achieving a technological breakthrough from passive flame retardancy to active fire extinguishing through an innovative dual-trigger mechanism and a multi-effect fire extinguishing system. The material uses perfluoropentanone fire extinguishing agent as the core material, and a composite wall material of thermoplastic resin and a photosensitive polymer containing azobenzene groups is adopted to form a microcapsule structure with a particle size of 10 - 600 μm through a fluidized bed coating process. Low melting point alloy particles (melting point 120 - 150 °C) and photosensitive materials are embedded in the wall material. When the fire temperature reaches the critical value or the light radiation intensity exceeds 50 kW / m², the wall material is triggered to rupture and release the fire extinguishing agent within 5 seconds. The material design adopts a double-layer wall material structure: the inner rapid-release layer is composed of gelatin / arabic gum, and the outer slow-release layer is ethyl cellulose. This gradient release design enables 30 - 50% of the core dose of the fire extinguishing agent to be released within 30 seconds after triggering, and the remaining part is continuously released through the slow-release layer for up to 45 minutes to ensure long-term suppression of the fire. The perfluoropentanone fire extinguishing agent acts through the synergistic effect of three mechanisms: absorbing heat and vaporizing to reduce the fire temperature, decomposing to generate free radicals to inhibit the combustion chain reaction, and forming an inert gas layer to isolate the oxygen supply, achieving a comprehensive fire extinguishing effect of cooling, suffocation, and chemical inhibition. The preparation process adopts ultrasonic emulsification combined with electrostatic repulsion, and the microcapsules remain uniformly dispersed during the storage period. The supercritical CO2 extraction process controls the residual solvent below 0.01%, improving the environmental performance. The optimization of the fluidized bed coating parameters (inlet air temperature 80 - 120 °C, atomization pressure 0.3 - 0.6 MPa) enables the wall thickness of the microcapsules to be uniformly controlled within 1 - 5 μm, and the fire extinguishing agent loading ≥ 65%. The materials in this application document can be widely used in lithium battery energy storage cabins, fireproof coatings for electronic devices, and intelligent fire extinguishing systems. In the application of battery packs, a light radiation enhancement coating (reflectivity ≥ 90% @ 300 - 400 nm) on the surface of the cabin can significantly improve the light-triggering efficiency; the electronic device protection component forms a 0.5 - 2 mm fireproof layer by dispersing microcapsules in a silicone matrix; the intelligent system integrates a temperature / light radiation composite sensor and a fire extinguishing agent recovery device to achieve closed-loop management of fire warning, rapid response, and resource recycling. Compared with traditional flame retardant materials, the response speed of this technology is improved, the fire extinguishing efficiency covers a wider spectrum of fire conditions, and no harmful substances are released, which is particularly suitable for the active fire prevention requirements of high-value scenarios such as precision instruments and new energy equipment. Through material design and process innovation, the technological upgrade in the field of fire protection is achieved.

[0033] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

[0034] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent in such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

Claims

1. A preparation method of a fire extinguishing, sealing and shock-absorbing material, characterized in that, Comprising: Under the condition of nitrogen protection and a nitrogen flow rate of 0.8 - 1.5 L / min, 50 - 100 parts by weight of modified MDI, 20 - 50 parts by weight of 6-functional polyether polyol, and 10 - 100 parts by weight of 3M1230 nano-capsule flame retardant are reacted at 55 ± 2 °C for 2 hours to form a prepolymer with an NCO content of 8 - 12%; 50 - 100 parts by weight of polyether polyol, 5 - 10 parts by weight of expandable graphite with a particle size of 80 - 300 mesh, and 3 - 8 parts by weight of nano-aerosil are subjected to ultrasonic treatment for 30 min, and then 1 - 3 parts by weight of cross-linking agent are added to form a polyol system; The prepolymer, the polyol system, and the perfluoropentanone system are mixed in a ratio of 1:0.2 - 0.5:0.3 - 0.6, and are cast and molded through a 6-stage static mixer at a shear rate of 1000 - 1500 s⁻¹. After curing, the preparation of the damping material is completed.

2. The preparation method of a fire extinguishing, sealing and shock-absorbing material as described in claim 1, characterized in that The polyether polyol is selected from one or more of types 1618, 104, 210, and 220; And / or, the specific surface area of the nano-aerosil ≥ 200 m² / g; And / or, the cross-linking agent is one or more of ethylene glycol, 1,4-butanediol, diethylene glycol, and dipropylene glycol; And / or, the hydroxyl value of the polyether polyol is 28 - 56 mgKOH / g, and the block distribution of propylene oxide in the molecular chain shows a gradient change.

3. The preparation method of a fire extinguishing, sealing and shock-absorbing material as claimed in claim 1, characterized in that, The cast and molded material is cured according to a gradient curing program of maintaining at 50 °C for 30 min, 80 °C for 60 min, and 120 °C for 90 min.

4. The preparation method of a fire extinguishing, sealing and shock-absorbing material according to claim 1, characterized in that, The mass ratio of the expandable graphite to the nano-aerosil is 1:0.3 - 1:0.6, the starting expansion temperature of the expandable graphite is 180 ± 5 °C, and the expansion volume ≥ 250 mL / g.

5. The preparation method of a fire extinguishing, sealing and shock-absorbing material according to claim 3, characterized in that, When adding the perfluoropentanone system, 2 - 5 parts by weight of amino-silane modified montmorillonite are added simultaneously. The interlayer cation exchange capacity of the amino-silane modified montmorillonite ≥ 100 mmol / 100 g, the particle size D50 ≤ 500 nm, the modifier is 3-aminopropyltriethoxysilane, and its addition amount accounts for 0.5 - 1.2% of the mass of the montmorillonite.

6. The preparation method of a fire extinguishing, sealing and shock-absorbing material as claimed in claim 5, wherein, The static mixer comprises at least six mixing units, each unit is composed of a 45° cross helical tooth structure, and the tooth gap width is 0.2 - 0.5 mm.

7. A fire extinguishing, sealing and shock-absorbing material, characterized in that, Prepared by the preparation method according to any one of claims 1 to 6.

8. A battery pack, characterized in that, Including a housing and an electric core arranged inside the housing, and the material of the housing is the damping material described in claim 7.

9. A connecting piece, characterized in that, Including a first flange and a second flange, the first flange and the second flange clamp a sealing gasket, and the material of the sealing gasket is the damping material described in claim 7.

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