A novel fire extinguishing agent microcapsule, and a preparation method and application thereof

Abstract

The application discloses a novel fire extinguishing agent microcapsule and belongs to the technical field of fire extinguishing agents, which comprises the following components in the following contents: a composite fire extinguishing core material and a double-layer composite wall material coated on the outside of the core material; the composite fire extinguishing core material comprises, in percentage by mass, perfluorohexanone 70-85%, an environmentally-friendly flame-retardant additive 10-20% and a heat conduction modifier 3-8%; the double-layer composite wall material comprises an inner layer modified urea-formaldehyde resin wall material and an outer layer polyethylene glycol modified polyurethane wall material; in the application, the material adopts a double-layer composite wall material structure, the inner layer guarantees storage stability and mechanical strength, and the outer layer realizes precise temperature-sensitive triggering, thereby completely solving the problems of easy leakage, easy mis-triggering and response lag of traditional microcapsules; the microcapsule has high coating rate, long storage life, the material takes perfluorohexanone as a core fire extinguishing component, is matched with trimethyl phosphate and a nano magnesium hydroxide compounded flame-retardant additive, can quickly isolate oxygen and inhibit chain combustion reaction during use, prevents afterglow, and improves fire extinguishing effect.

Description

Technical Field

[0001] This invention belongs to the field of fire extinguishing agent technology, and particularly relates to a novel fire extinguishing agent microcapsule, its preparation method, and its application. Background Technology

[0002] With the rapid development of the new energy industry, electronic information technology, and aerospace, the fire safety requirements for precision equipment, energy storage devices, and confined spaces are becoming increasingly stringent. Traditional dry powder fire extinguishing agents, water-based fire extinguishing agents, and gaseous fire extinguishing agents have significant shortcomings in application. Dry powder fire extinguishing agents are prone to residue and corrosion of precision equipment, and are difficult to clean; water-based fire extinguishing agents are highly conductive and cannot be used to extinguish fires involving electrical equipment; traditional halon gaseous fire extinguishing agents have low extinguishing efficiency and pose environmental pollution and ozone layer depletion problems.

[0003] Microcapsule fire extinguishing agents, with their advantages of stable encapsulation, targeted release, and no pollution, have become a research direction for new fire protection materials. Currently, most existing microcapsule fire extinguishing agents adopt a single core material and single-layer wall material structure, but they still have some drawbacks: First, the encapsulation process is not mature, the microcapsule encapsulation rate is low, the core material is prone to leakage, and the long-term storage stability is poor, making them prone to failure; second, the temperature-sensitive response performance is poor, with problems such as false triggering in normal and high temperature environments, excessively high fire triggering temperature, or delayed response, making it impossible to achieve rapid fire extinguishing; third, the fire extinguishing component is single, and the fire extinguishing activity decreases significantly in low temperature environments, limiting the applicable scenarios; fourth, the wall material has insufficient toughness and strength, making it easy to break during transportation and installation, resulting in poor practicality. In order to solve the above problems, there is an urgent need for a new type of fire extinguishing agent microcapsule, its preparation method, and its application. Summary of the Invention

[0004] The purpose of this invention is to provide a novel microcapsule for fire extinguishing agents, its preparation method, and its application in order to solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention employs the following technical solution: a novel fire extinguishing agent microcapsule, comprising the following components:

[0006] The fire extinguishing core material comprises a composite fire extinguishing core material and a double-layer composite wall material covering the outer side of the core material; the composite fire extinguishing core material, by mass percentage, comprises 70-85% perfluorohexanone, 10-20% environmentally friendly flame retardant additives, and 3-8% thermal conductivity modifiers; the double-layer composite wall material comprises an inner layer of modified urea-formaldehyde resin wall material and an outer layer of polyethylene glycol modified polyurethane wall material; the microcapsules have a particle size of 5-25 μm.

[0007] As a further description of the above technical solution:

[0008] The environmentally friendly flame retardant additive is a compound mixture of trimethyl phosphate and nano magnesium hydroxide, with a compound mass ratio of 2:1; the thermal conductivity modifier is nano silica-modified graphene micropowder with a particle size of 20-50 nm.

[0009] As a further description of the above technical solution:

[0010] The inner layer modified urea-formaldehyde resin wall material has a thickness of 0.8-1.5μm and is prepared by modifying urea-formaldehyde resin, melamine, and crosslinking agent; the outer layer polyethylene glycol modified polyurethane wall material has a thickness of 0.3-0.8μm and has temperature-sensitive cracking characteristics, rapidly cracking and releasing the core material fire extinguishing agent in high-temperature environments above 90℃.

[0011] This invention also discloses a method for preparing microcapsules of a novel fire extinguishing agent, the specific steps of which are as follows:

[0012] S1. Preparation of composite core material;

[0013] S2. Prepare the aqueous emulsion;

[0014] S3. Perform primary microcapsule preparation;

[0015] S4. Perform double-layer wall material modification coating;

[0016] S5. Perform post-processing and shaping.

[0017] As a further description of the above technical solution:

[0018] In step S1, the composite core material is prepared by mixing perfluorohexanone, environmentally friendly flame retardant additive, and thermal conductivity modifier according to the specified ratio, placing them in a constant temperature stirring tank, stirring for 20-30 minutes at 40-50℃ and 800-1000r / min, and then ultrasonically dispersing for 10-15 minutes to obtain a uniform and stable composite fire extinguishing core material for later use.

[0019] As a further description of the above technical solution:

[0020] In step S2, the aqueous emulsion is prepared by adding sodium dodecylbenzenesulfonate emulsifier to deionized water and stirring to dissolve it. Then, modified urea-formaldehyde resin prepolymer is added and stirred continuously until uniform to form a stable aqueous emulsion. The mass ratio of sodium dodecylbenzenesulfonate emulsifier to deionized water is 1:80-1:100, and the mass ratio of modified urea-formaldehyde resin prepolymer to emulsion system is 15-20%.

[0021] As a further description of the above technical solution:

[0022] In step S3, primary microcapsule preparation is carried out. The specific steps are as follows: the composite core material prepared in step S1 is slowly added dropwise to the aqueous emulsion in step S2, high-speed shear emulsification is performed for 15-20 min, the pH value of the system is adjusted to 4.5-5.5, the temperature is raised to 55-65℃, and the polymerization is carried out for 2-3 h to obtain a primary microcapsule emulsion with inner wall material. The mass ratio of the composite core material to the aqueous emulsion is 1:3-1:4, and the high-speed shear speed is controlled at 1200-1500 r / min.

[0023] As a further description of the above technical solution:

[0024] In step S4, a double-layer wall material modification coating is performed. The specific steps are as follows: polyethylene glycol modified polyurethane prepolymer is added dropwise to the primary microcapsule emulsion, the stirring speed is adjusted to 500-600 r / min, the temperature is raised to 60-70℃, and the reaction is maintained for 1.5-2.5 h to complete the outer wall material coating. The mass ratio of the polyethylene glycol modified polyurethane prepolymer to the primary microcapsule emulsion is 1:10-1:15.

[0025] As a further description of the above technical solution:

[0026] In step S5, post-processing and molding are carried out. The specific steps are as follows: after the reaction is completed, the mixture is naturally cooled to room temperature, filtered, centrifuged, washed 3-4 times alternately with deionized water and anhydrous ethanol, vacuum dried at 60-70℃ for 8-12 hours, and then sieved to obtain the novel fire extinguishing agent microcapsule product.

[0027] This invention also discloses the application of a novel fire extinguishing agent microcapsule, which can be used in automatic fire extinguishing and protection scenarios such as precision electronic equipment, energy storage power stations, data centers, aerospace equipment, and new energy battery warehouses. It can be used alone or in combination with water-based coatings, flame-retardant boards, and fire extinguishing patches.

[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0029] In this invention, the material adopts a double-layer composite wall structure. The inner layer ensures storage stability and mechanical strength, while the outer layer enables precise temperature-sensitive triggering, completely solving the problems of easy leakage, false triggering, and delayed response of traditional microcapsules. The microcapsules have a high coverage rate and a long storage life. The material uses perfluorohexanone as the core fire extinguishing component, combined with trimethyl phosphate and nano-magnesium hydroxide as a flame retardant additive. It can quickly isolate oxygen and inhibit chain combustion reactions during use, preventing reignition. This improves the fire extinguishing effect. Furthermore, the nano-modified graphene thermal conductivity modifier can enhance the thermal sensing rate of the microcapsules, enabling rapid fire identification and instantaneous release for fire extinguishing, thus improving the actual application effect of the product.

[0030] In this invention, the material microcapsules are non-toxic, non-corrosive, residue-free, environmentally friendly, and pollution-free. They will not damage precision electronic equipment or energy storage devices. At the same time, they have excellent high and low temperature resistance and can be used stably in extreme environments. They are suitable for high-end closed scenarios such as energy storage power stations, data centers, aerospace, and new energy batteries, and have a wide range of applications.

[0031] In this invention, the preparation process adopts a combination of in-situ polymerization and interfacial polymerization. The reaction conditions are mild and the parameters are controllable. No complex equipment is required. The product has uniform particle size and good consistency, can be mass-produced, has low production cost, and good application effect. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating a method for preparing microcapsules of a novel fire extinguishing agent. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0034] Example 1

[0035] Please see Figure 1 This invention provides a technical solution: a novel fire extinguishing agent microcapsule, comprising the following components in the following amounts:

[0036] The fire extinguishing core material comprises a composite fire extinguishing core material and a double-layer composite wall material covering the outer side of the core material; the composite fire extinguishing core material, by mass percentage, comprises 70-85% perfluorohexanone, 10-20% environmentally friendly flame retardant additives, and 3-8% thermal conductivity modifiers; the double-layer composite wall material comprises an inner layer of modified urea-formaldehyde resin wall material and an outer layer of polyethylene glycol modified polyurethane wall material; the microcapsules have a particle size of 5-25 μm.

[0037] The environmentally friendly flame retardant additive is a compound mixture of trimethyl phosphate and nano magnesium hydroxide, with a mass ratio of 2:1; the thermal conductivity modifier is nano silica-modified graphene micropowder with a particle size of 20-50 nm; the inner layer modified urea-formaldehyde resin wall material has a thickness of 0.8-1.5 μm and is prepared by modifying urea-formaldehyde resin, melamine, and crosslinking agent; the outer layer polyethylene glycol-modified polyurethane wall material has a thickness of 0.3-0.8 μm and has temperature-sensitive cracking characteristics, rapidly cracking and releasing the core material fire extinguishing agent at high temperatures above 90°C.

[0038] In this embodiment, the material adopts a double-layer composite wall structure. The inner layer ensures storage stability and mechanical strength, while the outer layer enables precise temperature-sensitive triggering, completely solving the problems of easy leakage, false triggering, and delayed response of traditional microcapsules. The microcapsules have a high coverage rate and a long storage life. The material uses perfluorohexanone as the core fire extinguishing component, combined with trimethyl phosphate and nano-magnesium hydroxide as a compound flame retardant additive. It can quickly isolate oxygen and inhibit chain combustion reactions during use, preventing reignition. This improves the fire extinguishing effect. Furthermore, the nano-modified graphene thermal conductivity modifier can enhance the thermal sensing rate of the microcapsules, enabling rapid fire identification and instantaneous release for fire extinguishing, thus improving the actual application effect of the product.

[0039] Furthermore, the material microcapsules are non-toxic, non-corrosive, residue-free, environmentally friendly, and pollution-free, and will not damage precision electronic equipment or energy storage devices. They also have excellent high and low temperature resistance, can be used stably in extreme environments, and can be adapted to high-end closed scenarios such as energy storage power stations, data centers, aerospace, and new energy batteries, with a wide range of applications.

[0040] Example 2

[0041] Please see Figure 1 This invention provides a technical solution: a method for preparing microcapsules of a novel fire extinguishing agent, the specific steps of which are as follows:

[0042] S1. Preparation of composite core material: The specific steps are as follows: Mix perfluorohexanone, environmentally friendly flame retardant additive and thermal conductivity modifier according to the formula, place them in a constant temperature stirring tank, stir for 20 minutes at 40℃ and 800r / min, and ultrasonically disperse for 10 minutes to obtain a uniform and stable composite fire extinguishing core material for later use.

[0043] S2. Prepare the aqueous emulsion by adding sodium dodecylbenzenesulfonate emulsifier to deionized water and stirring to dissolve it. Then add the modified urea-formaldehyde resin prepolymer and continue stirring until homogeneous to form a stable aqueous emulsion. The mass ratio of sodium dodecylbenzenesulfonate emulsifier to deionized water is 1:80-1:100, and the mass percentage of the modified urea-formaldehyde resin prepolymer to the emulsion system is 15%.

[0044] S3. Primary microcapsule preparation is carried out, specifically as follows: the composite core material prepared in step S1 is slowly added dropwise to the aqueous emulsion in step S2, high-speed shear emulsification is performed for 15 min, the pH value of the system is adjusted to 4.5, the temperature is raised to 55℃, and the polymerization is maintained for 2 h to obtain a primary microcapsule emulsion with inner wall material. The mass ratio of the composite core material to the aqueous emulsion is 1:3-1:4, and the high-speed shear speed is controlled at 1200 r / min.

[0045] S4. Perform double-layer wall material modification and coating. The specific steps are as follows: add polyethylene glycol modified polyurethane prepolymer dropwise to the primary microcapsule emulsion, adjust the stirring speed to 500 r / min, raise the temperature to 60℃, and keep the reaction at this temperature for 1.5 h to complete the outer wall material coating. The mass ratio of the polyethylene glycol modified polyurethane prepolymer to the primary microcapsule emulsion is 1:10-1:15.

[0046] S5. Post-processing and molding: After the reaction is completed, the mixture is naturally cooled to room temperature, filtered, centrifuged, washed three times with deionized water and anhydrous ethanol, dried under vacuum at 60°C for 8 hours, and then sieved to obtain the finished product of the novel fire extinguishing agent microcapsules.

[0047] In this embodiment, the preparation process adopts a combination of in-situ polymerization and interfacial polymerization. The reaction conditions are mild and the parameters are controllable. No complex equipment is required. The product has uniform particle size and good consistency, which can be mass-produced, with low production cost and good application effect.

[0048] Example 3

[0049] Please see Figure 1 This invention provides a technical solution: a method for preparing microcapsules of a novel fire extinguishing agent, the specific steps of which are as follows:

[0050] S1. Preparation of composite core material: The specific steps are as follows: Mix perfluorohexanone, environmentally friendly flame retardant additive and thermal conductivity modifier according to the ratio, place them in a constant temperature stirring tank, stir for 30 min at 50℃ and 1000 r / min, and ultrasonically disperse for 15 min to obtain a uniform and stable composite fire extinguishing core material for later use.

[0051] S2. Prepare the aqueous emulsion by adding sodium dodecylbenzenesulfonate emulsifier to deionized water and stirring to dissolve it. Then add the modified urea-formaldehyde resin prepolymer and continue stirring until homogeneous to form a stable aqueous emulsion. The mass ratio of sodium dodecylbenzenesulfonate emulsifier to deionized water is 1:80-1:100, and the mass ratio of modified urea-formaldehyde resin prepolymer to the emulsion system is 20%.

[0052] S3. Primary microcapsule preparation is carried out, specifically as follows: the composite core material prepared in step S1 is slowly added dropwise to the aqueous emulsion in step S2, high-speed shear emulsification is performed for 20 min, the pH value of the system is adjusted to 5.5, the temperature is raised to 65℃, and the polymerization is maintained for 3 h to obtain a primary microcapsule emulsion with inner wall material. The mass ratio of the composite core material to the aqueous emulsion is 1:3-1:4, and the high-speed shear speed is controlled at 1500 r / min.

[0053] S4. Perform double-layer wall material modification and coating. The specific steps are as follows: add polyethylene glycol modified polyurethane prepolymer dropwise to the primary microcapsule emulsion, adjust the stirring speed to 600 r / min, raise the temperature to 70℃, and keep the reaction at this temperature for 2.5 h to complete the outer wall material coating. The mass ratio of the polyethylene glycol modified polyurethane prepolymer to the primary microcapsule emulsion is 1:10-1:15.

[0054] S5. Post-processing and molding: After the reaction is completed, the mixture is naturally cooled to room temperature, filtered, centrifuged, washed 4 times alternately with deionized water and anhydrous ethanol, vacuum dried at 70℃ for 12 hours, and then sieved to obtain the new fire extinguishing agent microcapsule product.

[0055] Example 4

[0056] Please see Figure 1 This invention provides a technical solution: a method for preparing microcapsules of a novel fire extinguishing agent, the specific steps of which are as follows:

[0057] S1. Preparation of composite core material: The specific steps are as follows: Mix perfluorohexanone, environmentally friendly flame retardant additive and thermal conductivity modifier according to the ratio, place them in a constant temperature stirring tank, stir for 25 minutes at 45℃ and 900r / min, and ultrasonically disperse for 13 minutes to obtain a uniform and stable composite fire extinguishing core material for later use.

[0058] S2. Prepare the aqueous emulsion by adding sodium dodecylbenzenesulfonate emulsifier to deionized water and stirring to dissolve it. Then add the modified urea-formaldehyde resin prepolymer and continue stirring until homogeneous to form a stable aqueous emulsion. The mass ratio of sodium dodecylbenzenesulfonate emulsifier to deionized water is 1:80-1:100, and the mass percentage of the modified urea-formaldehyde resin prepolymer to the emulsion system is 18%.

[0059] S3. Primary microcapsule preparation is carried out, specifically as follows: the composite core material prepared in step S1 is slowly added dropwise to the aqueous emulsion in step S2, high-speed shear emulsification is performed for 18 min, the pH value of the system is adjusted to 5, the temperature is raised to 60℃, and the polymerization is maintained for 2 h to obtain a primary microcapsule emulsion with inner wall material. The mass ratio of the composite core material to the aqueous emulsion is 1:3-1:4, and the high-speed shear speed is controlled at 1300 r / min.

[0060] S4. Perform double-layer wall material modification and coating. The specific steps are as follows: add polyethylene glycol modified polyurethane prepolymer dropwise to the primary microcapsule emulsion, adjust the stirring speed to 550 r / min, raise the temperature to 65℃, keep the reaction at the temperature for 2 hours, and complete the outer wall material coating. The mass ratio of the polyethylene glycol modified polyurethane prepolymer to the primary microcapsule emulsion is 1:10-1:15.

[0061] S5. Post-processing and molding: After the reaction is completed, the mixture is naturally cooled to room temperature, filtered, centrifuged, washed 4 times alternately with deionized water and anhydrous ethanol, vacuum dried at 65℃ for 10 hours, and then sieved to obtain the new fire extinguishing agent microcapsule product.

[0062] Example 5

[0063] The present invention also provides a technical solution: the application of a novel fire extinguishing agent microcapsule in automatic fire extinguishing and protection scenarios for precision electronic equipment, energy storage power stations, data centers, aerospace equipment, and new energy battery warehouses. It can be used alone or in combination with water-based coatings, flame-retardant boards, and fire extinguishing patches.

[0064] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A novel microcapsule for a fire extinguishing agent, characterized in that, It includes the following components: The fire extinguishing core material comprises a composite fire extinguishing core material and a double-layer composite wall material covering the outer side of the core material; the composite fire extinguishing core material, by mass percentage, comprises 70-85% perfluorohexanone, 10-20% environmentally friendly flame retardant additives, and 3-8% thermal conductivity modifiers; the double-layer composite wall material comprises an inner layer of modified urea-formaldehyde resin wall material and an outer layer of polyethylene glycol modified polyurethane wall material; the microcapsules have a particle size of 5-25 μm.

2. The microcapsule of a novel fire extinguishing agent according to claim 1, characterized in that, The environmentally friendly flame retardant additive is a compound mixture of trimethyl phosphate and nano magnesium hydroxide, with a compound mass ratio of 2:1; the thermal conductivity modifier is nano silica-modified graphene micropowder with a particle size of 20-50 nm.

3. The microcapsule of a novel fire extinguishing agent according to claim 2, characterized in that, The inner layer modified urea-formaldehyde resin wall material has a thickness of 0.8-1.5μm and is prepared by modifying urea-formaldehyde resin, melamine, and crosslinking agent; the outer layer polyethylene glycol modified polyurethane wall material has a thickness of 0.3-0.8μm and has temperature-sensitive cracking characteristics, rapidly cracking and releasing the core material fire extinguishing agent in high-temperature environments above 90℃.

4. A method for preparing microcapsules of a novel fire extinguishing agent according to any one of claims 1-3, characterized in that, The specific steps are as follows: S1. Preparation of composite core material; S2. Prepare the aqueous emulsion; S3. Perform primary microcapsule preparation; S4. Perform double-layer wall material modification coating; S5. Perform post-processing and shaping.

5. The method for preparing microcapsules of a novel fire extinguishing agent according to claim 4, characterized in that, In step S1, the composite core material is prepared by mixing perfluorohexanone, environmentally friendly flame retardant additive, and thermal conductivity modifier according to the specified ratio, placing them in a constant temperature stirring tank, stirring for 20-30 minutes at 40-50℃ and 800-1000r / min, and then ultrasonically dispersing for 10-15 minutes to obtain a uniform and stable composite fire extinguishing core material for later use.

6. The method for preparing microcapsules of a novel fire extinguishing agent according to claim 4, characterized in that, In step S2, the aqueous emulsion is prepared by adding sodium dodecylbenzenesulfonate emulsifier to deionized water and stirring to dissolve it. Then, modified urea-formaldehyde resin prepolymer is added and stirred continuously until uniform to form a stable aqueous emulsion. The mass ratio of sodium dodecylbenzenesulfonate emulsifier to deionized water is 1:80-1:100, and the mass ratio of modified urea-formaldehyde resin prepolymer to emulsion system is 15-20%.

7. The method for preparing microcapsules of a novel fire extinguishing agent according to claim 4, characterized in that, In step S3, primary microcapsule preparation is carried out. The specific steps are as follows: the composite core material prepared in step S1 is slowly added dropwise to the aqueous emulsion in step S2, high-speed shear emulsification is performed for 15-20 min, the pH value of the system is adjusted to 4.5-5.5, the temperature is raised to 55-65℃, and the polymerization is carried out for 2-3 h to obtain a primary microcapsule emulsion with inner wall material. The mass ratio of the composite core material to the aqueous emulsion is 1:3-1:4, and the high-speed shear speed is controlled at 1200-1500 r / min.

8. The method for preparing microcapsules of a novel fire extinguishing agent according to claim 4, characterized in that, In step S4, a double-layer wall material modification coating is performed. The specific steps are as follows: polyethylene glycol modified polyurethane prepolymer is added dropwise to the primary microcapsule emulsion, the stirring speed is adjusted to 500-600 r / min, the temperature is raised to 60-70℃, and the reaction is maintained for 1.5-2.5 h to complete the outer wall material coating. The mass ratio of the polyethylene glycol modified polyurethane prepolymer to the primary microcapsule emulsion is 1:10-1:

15.

9. The method for preparing microcapsules of a novel fire extinguishing agent according to claim 4, characterized in that, In step S5, post-processing and molding are carried out. The specific steps are as follows: after the reaction is completed, the mixture is naturally cooled to room temperature, filtered, centrifuged, washed 3-4 times alternately with deionized water and anhydrous ethanol, vacuum dried at 60-70℃ for 8-12 hours, and then sieved to obtain the novel fire extinguishing agent microcapsule product.

10. The application of a novel fire extinguishing agent microcapsule, characterized in that: It is applicable to automatic fire extinguishing and protection scenarios in precision electronic equipment, energy storage power stations, data centers, aerospace equipment, and new energy battery warehouses. It can be used alone or in combination with water-based coatings, flame-retardant boards, and fire extinguishing patches.

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