Perfluorohexanone microcapsule explosion suppressant as well as preparation method and application thereof

Abstract

The invention discloses a perfluorohexanone microcapsule explosion suppressant as well as a preparation method and application thereof, and belongs to the technical field of explosion-proof materials. The preparation method comprises the following steps: dissolving perfluorohexanone and a bifunctional isocyanate monomer in an organic solvent to obtain an oil phase; adding an emulsifier into water, adding the oil phase while stirring, and continuously stirring to obtain an emulsion; and dropwise adding a cross-linking agent and an initiator into the emulsion while stirring, reacting, filtering, washing, and freeze-drying to obtain the micro perfluorohexanone microcapsule explosion suppressant. The prepared perfluorohexanone microcapsule explosion suppressant is uniform in particle size, the capsule wall thickness and hardness are moderate, mass preparation can be met, storage is easy, meanwhile, core material substances are easy to release, and the explosion suppression performance is not affected. The perfluorohexanone microcapsule explosion suppressant disclosed by the invention has good explosion suppression performance, can be widely applied to flammable and combustible equipment places such as aviation, chemical engineering and the like and fine equipment places such as energy storage power stations and the like, and can effectively suppress explosion caused by combustible gas and liquid.

Description

Technical Field

[0001] The invention belongs to the technical field of explosion-proof materials, and specifically relates to a perfluorohexanone microcapsule explosion suppressant and a preparation method and application thereof. Background Art

[0002] In the existing explosion-proof technology, perfluorohexanone is widely used in aviation, chemical industry and other fields as a fire extinguishing agent. However, perfluorohexanone is volatile and requires a suitable release mechanism during use to effectively suppress fire or explosion. Therefore, it is urgent to develop a microcapsule technology that can effectively encapsulate perfluorohexanone and release it under specific conditions to improve its stability and safety. Traditional explosion suppressants have problems such as uneven release and failure to reach the explosion response surface, and cannot fully meet the explosion-proof requirements in different environments. Therefore, it is of great significance to study a new type of perfluorohexanone microcapsule explosion suppressant and its preparation method. Summary of the invention

[0003] The invention provides a perfluorohexanone microcapsule explosion suppressant and a preparation method and application thereof, so as to solve the problem that the release of the existing explosion suppressants is difficult to control, and improve the stability and release efficiency of perfluorohexanone in the explosion-proof process.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing a perfluorohexanone microcapsule explosion suppressant, comprising the following steps:

[0006] (1) preparing an oil phase: dissolving perfluorohexanone and a difunctional isocyanate monomer in an organic solvent to obtain an oil phase;

[0007] (2) Emulsification: adding an emulsifier to water, adding the oil phase obtained in step (1) while stirring, and continuing to stir to obtain an emulsion;

[0008] (3) Interfacial polymerization: slowly dropwise adding a crosslinking agent and an initiator into the emulsion obtained in step (2) while stirring, reacting, filtering, washing, and freeze-drying to obtain the microperfluorohexanone microcapsule explosion inhibitor.

[0009] As a preferred technical solution of the present invention, in step (1), the difunctional isocyanate monomer includes one or more of isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, tetramethyl-m-xylylene diisocyanate, diphenylmethane diisocyanate and toluene diisocyanate; the organic solvent includes one or more of methyl nonafluorobutyl ether, perfluorobutyl methyl ether, nonafluorobutyl methyl ether, perfluorononene, 2-methoxy-3-trifluoromethyloctafluorobutane, 3-methoxyperfluoro(2-methylpentane), perfluoro-4-methyl-2-pentene, heptafluoropropane and perfluorohexane; the mass ratio of perfluorohexanone to the difunctional isocyanate monomer is (42-47):1.

[0010] As a preferred technical solution of the present invention, in step (2), the emulsifier includes sodium dodecyl sulfate and / or tween-80; the amount of the emulsifier added is 2 to 4 wt % of the oil phase, the stirring speed is 1500 to 2500 rpm, and the stirring time is 0.5 to 1.5 h.

[0011] As a preferred technical solution of the present invention, in step (3), the stirring speed is 200-400 rpm, the cross-linking agent is a compound containing two or more amino structures; the mass ratio of the cross-linking agent to the bifunctional isocyanate monomer in step (1) is (1.5-2.5):1; the initiator includes at least one of dibutyltin dilaurate, benzoyl peroxide, lauroyl peroxide, tert-butyl perbenzoate, diisopropyl peroxydicarbonate, azobisisobutyronitrile, azobisisoheptylnitrile and azoisobutylcyanoformamide; the mass ratio of the initiator to the bifunctional isocyanate monomer in step (1) is 1:(3-5).

[0012] As a preferred technical solution of the present invention, the cross-linking agent is a polyethylene polyamine series compound, including one or more of ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

[0013] As a preferred technical solution of the present invention, in step (3), the reaction temperature is 20 to 30° C. and the reaction time is 2 to 5 hours.

[0014] As a preferred technical solution of the present invention, the amount of perfluorohexanone used is 70-90% of the total mass of all raw materials (perfluorohexanone, difunctional isocyanate monomer, organic solvent, emulsifier, crosslinking agent and initiator) except water.

[0015] The present invention also provides a perfluorohexanone microcapsule explosion suppressant prepared according to the above-mentioned preparation method of the perfluorohexanone microcapsule explosion suppressant.

[0016] The present invention also provides an application of the above-mentioned perfluorohexanone microcapsule explosion suppressant in fire extinguishing and explosion suppressing materials.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The perfluorohexanone microcapsule explosion suppressant prepared by the method of the present invention has a particle size range of 150 to 200 μm, a uniform particle size, and a capsule wall thickness, moderate hardness and softness, which can meet the requirements of large-scale preparation and easy storage. At the same time, the core material is easy to release and does not affect the explosion suppression performance.

[0019] (2) The perfluorohexanone microcapsule explosion suppressant of the present invention has good explosion suppression performance and can be widely used in flammable and explosive places such as aviation and chemical industry as well as fine equipment places such as energy storage power stations, and can effectively suppress explosions caused by combustible gases and liquids. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a flow chart of preparing perfluorohexanone microcapsule explosion suppressant in Example 1;

[0022] Figure 2 This is a scanning electron microscope image of the perfluorohexanone microcapsule explosion suppressant prepared in Example 1;

[0023] Figure 3 This is a scanning electron microscope image of the perfluorohexanone microcapsule explosion suppressant prepared in Example 2;

[0024] Figure 4 In the figure, (a), (b) and (c) are scanning electron microscope images of the perfluorohexanone microcapsule explosion suppressant prepared in Examples 3 to 5, respectively;

[0025] Figure 5 The figure is a graph showing the explosion suppression effect of the perfluorohexanone microcapsule explosion suppressant prepared in Examples 1 to 5 and Comparative Examples 1 to 2 on hydrogen. DETAILED DESCRIPTION

[0026] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0027] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0028] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0029] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0030] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0031] Example 1

[0032] According to the types and amounts of raw materials in Table 1, the perfluorohexanone microcapsule explosion suppressant was prepared in the following steps:

[0033] Table 1 Amount of each raw material

[0034]

[0035] (1) preparing an oil phase: dissolving perfluorohexanone and a difunctional isocyanate monomer in an organic solvent to obtain an oil phase;

[0036] (2) Emulsification: Add an emulsifier into water, add the oil phase obtained in step (1) while stirring (2000 r / min), and continue stirring (2000 r / min) for 10 min to obtain an emulsion;

[0037] (3) Interfacial polymerization: Slowly add the second crosslinking agent and the initiator to the emulsion obtained in step (2) while stirring (300 r / min), react at room temperature (25° C.) for 3 h, filter, and rinse the obtained precipitate repeatedly with deionized water and anhydrous ethanol for 3 times, and then freeze-dry to obtain the micro-perfluorohexanone microcapsule explosion inhibitor.

[0038] The flow chart of preparing perfluorohexanone microcapsule explosion inhibitor in this embodiment is as follows Figure 1 shown.

[0039] The scanning electron microscope image of the perfluorohexanone microcapsule explosion inhibitor prepared in this example is as follows Figure 2 As shown by Figure 2 It can be seen that the particle size of the prepared microcapsules is 160-200 μm, and there are no cracks on the surface of the microcapsules to avoid accidental leakage and volatilization of the contents.

[0040] Example 2

[0041] Perfluorohexanone microcapsule explosion suppressant was prepared according to the types and amounts of raw materials in Table 2, and the steps were the same as those in Example 1.

[0042] Table 2 Amount of each raw material

[0043]

[0044]

[0045] The scanning electron microscope image of the perfluorohexanone microcapsule explosion inhibitor prepared in this example is as follows Figure 3 As shown. Figure 3 It can be seen that the microcapsules prepared in this example have regular shapes. By replacing isophorone diisocyanate and diethylenetriamine, the adaptability of the cross-linking agent used to the formation of the microcapsule shell wall is verified, showing that the combination of different isocyanate and amine compounds can regulate the wall material structure and wall thickness of the microcapsule, and microcapsules with suitable wall thickness can be obtained as needed.

[0046] Embodiments 3 to 5

[0047] The dosage of perfluorohexanone was adjusted, and the microcapsule explosion suppressant was prepared using perfluorohexanone with different contents in Table 3, and the steps were the same as those in Example 1.

[0048] Table 3 Amount of each raw material

[0049]

[0050] The scanning electron microscope images of the perfluorohexanone microcapsule explosion suppressants prepared in Example 3, Example 4 and Example 5 are shown in FIG. Figure 4 As shown in (a), (b) and (c). Figure 4 It can be seen that when the content of perfluorohexanone is 70wt%, the shell wall of the microcapsule is thinner and softer, and the shape of the microcapsule is uneven. When the content reaches 80wt%, the shape of the microcapsule is uniform but the shell wall is softer, and the core material is easy to release. When it is 90wt%, the shell wall thickness is moderate, which can meet the needs of large-scale preparation and easy storage without affecting the explosion suppression performance.

[0051] Comparative Example 1

[0052] Same as Example 1, except that the reaction temperature in step (3) is adjusted from room temperature to 40°C.

[0053] Comparative Example 2

[0054] Same as Example 1, except that the stirring speed in step (3) is adjusted from 300 r / min to 600 r / min.

[0055] Verify the explosion suppression effect of the perfluorohexanone microcapsule explosion suppressant prepared in Examples 1 to 5 and Comparative Examples 1 to 2 on hydrogen: add different amounts of explosion suppressant to a 20L standard explosion test device, mix 20vol% H2 with air to form a gaseous mixture. After a delay of 90ms, ignite and detonate the mixture, and measure the maximum pressure suppression curve of each group of products on 20vol% H2 explosion as shown in the following figure: Figure 5 As shown in . Figure 5 It can be seen that: in the comparative example, increasing the reaction temperature and increasing the stirring speed will reduce the explosion suppression effect of the microcapsules, while in the examples, making reasonable adjustments within the preferred embodiment of the present invention will not have much impact on the suppression effect of the microcapsules, indicating that the microcapsules prepared by the scheme of the present invention can achieve a better explosion suppression effect.

[0056] The above description is only a preferred specific implementation manner of the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a perfluorohexanone microcapsule explosion suppressant, characterized in that: The following steps are involved: (1) preparing an oil phase: dissolving perfluorohexanone and a difunctional isocyanate monomer in an organic solvent to obtain an oil phase; (2) Emulsification: adding an emulsifier to water, adding the oil phase obtained in step (1) while stirring, and continuing to stir to obtain an emulsion; (3) Interfacial polymerization: adding a crosslinking agent and an initiator dropwise to the emulsion obtained in step (2) while stirring, reacting, filtering, washing, and freeze-drying to obtain the microperfluorohexanone microcapsule explosion inhibitor.

2. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 1, characterized in that: In step (1), the difunctional isocyanate monomer includes one or more of isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, tetramethyl-m-xylylene diisocyanate, diphenylmethane diisocyanate and toluene diisocyanate; the organic solvent includes one or more of methyl nonafluorobutyl ether, perfluorobutyl methyl ether, nonafluorobutyl methyl ether, perfluorononene, 2-methoxy-3-trifluoromethyloctafluorobutane, 3-methoxyperfluoro(2-methylpentane), perfluoro-4-methyl-2-pentene, heptafluoropropane and perfluorohexane; the mass ratio of perfluorohexanone to the difunctional isocyanate monomer is (42-47):

1.

3. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 1, characterized in that: In step (2), the emulsifier includes sodium dodecyl sulfate and / or tween-80; the amount of the emulsifier added is 2-4wt% of the oil phase, the stirring speed is 1500-2500rpm, and the stirring time is 0.5-1.5h.

4. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 1, characterized in that: In step (3), the stirring speed is 200-400 rpm, the cross-linking agent is a compound containing two or more amino structures; the mass ratio of the cross-linking agent to the difunctional isocyanate monomer in step (1) is (1.5-2.5):1; the initiator includes at least one of dibutyltin dilaurate, benzoyl peroxide, lauroyl peroxide, tert-butyl perbenzoate, diisopropyl peroxydicarbonate, azobisisobutyronitrile, azobisisoheptylnitrile and azoisobutylcyanoformamide; the mass ratio of the initiator to the difunctional isocyanate monomer in step (1) is 1:(3-5).

5. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 4, characterized in that: The cross-linking agent is a polyethylene polyamine series compound, including one or more of ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

6. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 1, characterized in that: In step (3), the reaction temperature is 20-30° C. and the reaction time is 2-5 h.

7. The method for preparing the perfluorohexanone microcapsule explosion suppressant according to claim 1, characterized in that: The amount of perfluorohexanone used is 70-90% of the total mass of all raw materials except water.

8. A perfluorohexanone microcapsule explosion inhibitor prepared according to the method for preparing a perfluorohexanone microcapsule explosion inhibitor according to any one of claims 1 to 7.

9. Use of the perfluorohexanone microcapsule explosion suppressant according to claim 8 in fire extinguishing and explosion suppression materials.

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