A fire extinguishing microcapsule containing cis-hexafluorobutene, its preparation method and application

Abstract

This invention discloses a fire extinguishing microcapsule containing cis-hexafluorobutene, its preparation method, and its application, belonging to the field of fire extinguishing agent application technology. A fire extinguishing microcapsule containing cis-hexafluorobutene includes a core and a melamine polymer encapsulated around the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine. This invention also discloses a preparation method, including the following steps: emulsifying 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine in an emulsifier to obtain an emulsion containing the core; adding a melamine prepolymer to the emulsion containing the core; adding an acidic solution to adjust the pH value and carrying out a polymerization reaction; filtering and drying to obtain the fire extinguishing microcapsule. When the fire extinguishing microcapsule of this invention interacts with flames, it releases a large amount of CF3 and CF2 free radicals, which combine with free radicals in the fire scene, effectively inhibiting the generation of HF, achieving active fire prevention, and is easy to store at room temperature.

Description

Technical Field

[0001] This invention belongs to the field of fire extinguishing agent application technology, specifically relating to a fire extinguishing microcapsule containing cis-hexafluorobutene, its preparation method, and its application. Background Technology

[0002] Fluorinated fire retardants are chemicals commonly used in fire-retardant materials. They introduce fluorinated compounds into the material to provide the ability to suppress flames and delay combustion. Here are some common fluorinated fire retardants:

[0003] Halogenated flame retardants: One common type of fluorinated fire retardant is the halogenated flame retardant, such as bromides, chlorides, and fluorocarbons. These compounds can release halogen atoms at high temperatures, reacting with free radicals and inhibiting the spread of flame.

[0004] Fluorinated polymers: Fluorinated polymers exhibit low flammability due to the high electronegativity of fluorine atoms, which contributes to their high stability within the molecular chain. They can be used to prepare various fire-retardant coatings, insulating materials, and plastics.

[0005] Non-halogenated flame retardants: In recent years, due to the potential environmental and human health impacts of halogenated flame retardants, researchers have been developing non-halogenated flame retardants, such as phosphorus-nitrogen and silicon-nitrogen flame retardants. These flame retardants provide fire protection while reducing potential environmental hazards.

[0006] Applications of nanomaterials: The development of nanotechnology has also provided new possibilities for the research of fire-retardant materials. For example, nanomaterials such as nano-alumina and titanium dioxide can improve the fire-retardant properties of polymers and increase their thermal stability and mechanical strength.

[0007] Existing fluorinated fire extinguishing agents contain fluorine atoms in their fluorinated polymers, which have a strong affinity for hydrogen. During combustion or fire extinguishing, these atoms combine with surrounding hydrogen atoms to form the toxic gas hydrogen fluoride, and the extinguishing process is time-consuming.

[0008] cis-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz(Z)) is a hydrofluoroolefin with the molecular formula C4H2F6, and is an environmentally friendly fire extinguishing agent. At room temperature, it is a colorless and transparent liquid. Under the influence of high-temperature flames, its pyrolysis produces fluorine-containing free radicals that react with OH and H free radicals in the flame, thus halting the chain reaction of combustion. Furthermore, it has a zero ozone depletion potential (ODP) and a low global warming potential (GWP), and possesses high latent heat of vaporization and specific heat, values ​​higher than or close to perfluorohexanone, meeting the initial requirements for a new type of clean fire extinguishing agent. However, due to its boiling point of 33.4℃, it readily vaporizes and evaporates, making it difficult to store and apply.

[0009] In summary, existing fluorinated fire extinguishing agents have the following technical drawbacks: they take a long time to extinguish fires; they produce toxic gases during the extinguishing process; and they are prone to vaporization and volatilization, making them difficult to transport and store. Summary of the Invention

[0010] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a fire extinguishing microcapsule containing cis-hexafluorobutene, which solves the technical problems of existing fire extinguishing agents having long extinguishing time, generating hydrogen fluoride gas during the extinguishing process, and being difficult to transport and store.

[0011] To achieve the above-mentioned technical objectives, the present invention provides a fire extinguishing microcapsule containing cis-hexafluorobutene, comprising a core and a melamine polymer encapsulated around the core, wherein the core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine.

[0012] cis-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz(Z)) is a novel clean fire extinguishing agent. Cis-hexafluorobutene exhibits a positive synergistic fire extinguishing effect with perfluorotriethylamine (PFMA). Furthermore, PFMA does not contain hydrogen (H) in its molecule. When the extinguishing microcapsules interact with the flame, they release a large number of CF3 and CF2 free radicals, which combine with free radicals in the fire environment, effectively inhibiting the formation of the toxic product HF. After the core is released, the melamine polymer absorbs heat, thereby reducing the temperature around the flame. This endothermic effect effectively inhibits the spread of the fire and slows its development.

[0013] Preferably, the molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine is 4-5:1.

[0014] Preferably, the particle size of the fire extinguishing microcapsules is 40μm to 200μm.

[0015] If the particle size of the fire extinguishing microcapsules is too small, the amount of fire extinguishing material in the core-shell structure will be less, resulting in a lower content of fire extinguishing agent for the same mass. Furthermore, the microcapsule shell will be destroyed more slowly, leading to slower fire extinguishing. If the particle size of the fire extinguishing microcapsules is too large, the shell structure will be too thin, and the effective fire extinguishing ingredients in the core will easily volatilize, making it difficult to store.

[0016] Preferably, the fire extinguishing microcapsule has a fire extinguishing trigger temperature of 70–110°C.

[0017] When the ambient temperature reaches or exceeds the preset minimum trigger temperature (70°C) of the microcapsule, the extinguishing agent inside the microcapsule will begin to be released. As the temperature continues to rise and reaches or exceeds the maximum trigger temperature, all the extinguishing agent inside the microcapsule will be released for fire extinguishing.

[0018] This trigger temperature range is designed to ensure that, in the event of a fire, the extinguishing agent is released only when the temperature rises to a certain level, rather than being released at normal temperatures. This helps avoid false triggering and provides more reliable fire extinguishing performance. The extinguishing microcapsules of this invention are more stable during room temperature storage, which is beneficial for storage.

[0019] A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene as described above includes the following steps:

[0020] S1. 1,1,1,4,4,4-Hexafluoro-2-butene and perfluorotriethylamine are added to an emulsifier at 10℃~15℃ (mixed), stirred, dispersed, and emulsified to obtain an emulsion containing a core. The stirring speed and emulsification time in this step can control the particle size of the fire extinguishing microcapsules. Higher stirring speeds and longer emulsification times generally result in smaller particle sizes of the fire extinguishing microcapsules. Conversely, lower stirring speeds and shorter emulsification times may lead to larger particle sizes of the fire extinguishing microcapsules.

[0021] S2. Add the melamine prepolymer to the emulsion containing the core to obtain the polymerization reaction solution;

[0022] S3. Add an acidic solution to adjust the pH of the polymerization reaction solution to 3-4, and keep it at this temperature for 5-6 hours to carry out the polymerization reaction;

[0023] S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

[0024] Preferably, the emulsifier in S1 is one or more of styrene-maleic anhydride sodium salt, sodium dodecyl sulfate, and sodium dodecylbenzene sulfonate.

[0025] Preferably, the stirring speed in S1 is 200 r / min to 1500 r / min, and the emulsification time is 10 min to 20 min.

[0026] Preferably, the melamine prepolymer is a water-soluble melamine prepolymer, and the melamine prepolymer is one of FN-9010 resin, MF4750 resin from Xinli Chemical, and CYMEL 385 resin.

[0027] Preferably, the acidic solution is one or more of oxalic acid, citric acid, acetic acid, boric acid, dilute sulfuric acid, dilute hydrochloric acid, dilute nitric acid, and dilute phosphoric acid.

[0028] An application of fire extinguishing microcapsules containing cis-hexafluorobutene, as described above, is proposed, in which the fire extinguishing microcapsules can be used as raw materials in the production of fire blankets, fire extinguishing sheets, fire extinguishing coatings, and fire extinguishing fibers.

[0029] Fire extinguishing microcapsules feature a special thin-film material. When exposed to external heat, the internal extinguishing agent core gradually expands until it breaks through the microcapsule wall membrane and is released. The extinguishing agent then achieves its extinguishing effect through a chain reaction of physical cooling, isolation, and chemical inhibition to interrupt combustion. Microencapsulating the extinguishing agent effectively prevents its volatilization and leakage during storage and use.

[0030] cis-1,1,1,4,4,4-hexafluoro-2-butene (HFE-236fa) is a fluorocarbon with excellent physical properties and environmental friendliness. It has low surface tension and high vapor pressure, allowing it to evaporate rapidly in air and form a flammable layer to suppress fires. By forming this flammable layer, HFE-236fa blocks the combustion zone from contacting the surrounding oxygen, thus weakening the flame's ability to burn.

[0031] Perfluorotriethylamine (FT3EA) is a reactive gaseous fire extinguishing agent with a low critical temperature and pressure. When a flame burns, FT3EA releases fluorine atoms. These fluorine atoms react with free radicals (such as hydroxyl radicals) in the flame in the presence of oxygen to form stable fluorooxy radicals, thereby inhibiting the chain reaction of free radicals in the flame. This process is called fluorination and can effectively suppress the combustion process of the flame.

[0032] HFE-236fa not only forms a flaring layer but also absorbs heat, lowering the fire temperature and slowing down the combustion reaction. This provides better working conditions for FT3EA, making it easier for it to react with free radicals in the flame. The fluorination reaction of FT3EA can also inhibit the chain reaction of the flame, thereby weakening the flame's combustion capacity and increasing the fire extinguishing effect of HFE-236fa, achieving a synergistic effect between the two.

[0033] Compared with existing technologies, the beneficial effects of this invention include: when the fire extinguishing microcapsules interact with flames, they release more CF3 and CF2 free radicals, which combine with free radicals in the fire scene, thereby effectively inhibiting the generation of toxic product HF; by selecting a suitable particle size for the fire extinguishing microcapsules, the fire extinguishing agent is ensured to have low volatility while maintaining its fire extinguishing effect; the fire extinguishing microcapsules have a trigger temperature of 70-110℃, achieving active fire prevention; the fire extinguishing microcapsules only function when the temperature is higher than the trigger temperature; the fire extinguishing microcapsules of this invention are relatively stable when stored at room temperature, facilitating storage and transportation, and preventing volatilization and leakage; the fire extinguishing microcapsules of this invention can also be composited with various materials and interfaces, and applied in fire blankets, fire extinguishing pads, and other equipment, as well as in the preparation of coatings and fibers with fire extinguishing functions, with a wide range of applications. Attached Figure Description

[0034] Figure 1The image shows the microstructure of a fire extinguishing microcapsule containing cis-hexafluorobutene, provided in a specific embodiment of the present invention.

[0035] Figure 2 This is a diagram illustrating the fire extinguishing process of a fire extinguishing tablet prepared from fire extinguishing microcapsules containing cis-hexafluorobutene, as provided in a specific embodiment of the present invention.

[0036] Figure 3 This is a diagram illustrating another fire extinguishing process of a fire extinguishing tablet prepared from a fire extinguishing microcapsule containing cis-hexafluorobutene, as provided in a specific embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] Example 1

[0039] This embodiment provides a fire extinguishing microcapsule containing cis-hexafluorobutene, comprising a core and a melamine polymer encapsulating the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine. The molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine is 4:1. The particle size of the fire extinguishing microcapsule is 200 μm, and the fire extinguishing trigger temperature of the fire extinguishing microcapsule is 70°C.

[0040] A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene as described in this embodiment includes the following steps:

[0041] S1. Add styrene maleic anhydride to water and stir. Heat to 90°C and add sodium hydroxide aqueous solution. Heat until dissolved and transparent to obtain a 6% styrene maleic anhydride salt aqueous solution. Add 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine to the styrene maleic anhydride emulsifier at 10°C, mix and stir, disperse, and emulsify to obtain an emulsion containing a core. The stirring speed is 200 r / min, and the emulsification time is 10 min.

[0042] S2. Add melamine prepolymer CYMEL 385 to the emulsion containing the core to obtain a polymerization reaction solution;

[0043] S3. Add citric acid to adjust the pH of the polymerization reaction solution to 3, and keep it at this temperature for 6 hours to carry out the polymerization reaction;

[0044] S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

[0045] The application of the fire extinguishing microcapsule containing cis-hexafluorobutene described in this embodiment can be used as a raw material in the production of fire blankets, fire extinguishing sheets, fire extinguishing coatings, and fire extinguishing fibers.

[0046] The microstructure of the fire extinguishing microcapsules obtained in this embodiment is shown in the figure below. Figure 1 .

[0047] Example 2

[0048] This embodiment provides a fire extinguishing microcapsule containing cis-hexafluorobutene, comprising a core and a melamine polymer encapsulating the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine. The molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine is 4:1. The particle size of the fire extinguishing microcapsule is 40 μm, and the fire extinguishing trigger temperature of the fire extinguishing microcapsule is 110°C.

[0049] A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene as described in this embodiment includes the following steps:

[0050] S1. At 15℃, 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine were added to sodium dodecyl sulfate emulsifier, mixed and stirred, dispersed and emulsified to obtain an emulsion containing a core. The stirring speed was 1500 r / min and the emulsification time was 20 min.

[0051] S2. Add melamine prepolymer energy-rich resin FN-9010 to the emulsion containing the core to obtain a polymerization reaction solution;

[0052] S3. Add oxalic acid to adjust the pH of the polymerization reaction solution to 4, and keep it at this temperature for 5 hours to carry out the polymerization reaction;

[0053] S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

[0054] Example 3

[0055] This embodiment provides a fire extinguishing microcapsule containing cis-hexafluorobutene, comprising a core and a melamine polymer encapsulating the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine. The molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine is 5:1. The particle size of the fire extinguishing microcapsule is 50 μm, and the fire extinguishing trigger temperature of the fire extinguishing microcapsule is 100°C.

[0056] A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene as described in this embodiment includes the following steps:

[0057] S1. At 12℃, 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine were added to sodium dodecylbenzenesulfonate emulsifier, mixed and stirred, dispersed, and emulsified to obtain an emulsion containing a core. The stirring speed was 1500 r / min and the emulsification time was 15 min.

[0058] S2. Add melamine prepolymer Xinli Chemical MF475 to the emulsion containing the core to obtain a polymerization reaction solution;

[0059] S3. Add acetic acid to adjust the pH of the polymerization reaction solution to 4, and keep it at this temperature for 6 hours to carry out the polymerization reaction;

[0060] S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

[0061] Example 4

[0062] This embodiment provides a fire extinguishing microcapsule containing cis-hexafluorobutene, comprising a core and a melamine polymer encapsulating the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine. The molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine is 4.5:1. The particle size of the fire extinguishing microcapsule is 70 μm, and the fire extinguishing trigger temperature of the fire extinguishing microcapsule is 90°C.

[0063] A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene as described in this embodiment includes the following steps:

[0064] S1. At 10℃, 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine were added to styrene-maleic anhydride sodium salt emulsifier, mixed and stirred, dispersed, and emulsified to obtain an emulsion containing a core. The stirring speed was 1200 r / min and the emulsification time was 15 min.

[0065] S2. Add melamine prepolymer CYMEL 385 resin to the emulsion containing the core to obtain a polymerization reaction solution;

[0066] S3. Add boric acid to adjust the pH of the polymerization reaction solution to 3.5, and keep it at this temperature for 5.5 hours to carry out the polymerization reaction;

[0067] S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

[0068] Comparative Example 1

[0069] This comparative example is the same as Example 1, except that the core in this comparative example contains only cis-1,1,1,4,4,4-hexafluoro-2-butene.

[0070] Comparative Example 2

[0071] This comparative example is the same as Example 1, except that in this comparative example S1, the stirring speed is 2500 r / min, the emulsification time is 40 min, and the particle size of the fire extinguishing microcapsules in this comparative example is 15 μm.

[0072] Comparative Example 3

[0073] This comparative example is the same as Example 1, except that in this comparative example S1, the stirring speed is 150 r / min and the particle size of the fire extinguishing microcapsules is 300 μm.

[0074] The fire extinguishing microcapsules from Examples 1 to 4 and Comparative Examples 1 to 2 were made into fire extinguishing discs of equal volume and thickness, and fire extinguishing tests were conducted. The fire extinguishing performance was tested using the cup burner method. The fire extinguishing microcapsule discs were placed above the flame, and the time for the flame to extinguish was recorded. The fire extinguishing performance of the fire extinguishing discs made from the fire extinguishing microcapsules in Example 1 is as follows: Figure 2 and Figure 3 As shown, Figure 2 This is a diagram showing the initial state of the flames. Figure 3 This diagram shows the burning situation when the flames are about to go out. The extinguishing time for each group of fire extinguishing discs is shown in Table 1.

[0075] Table 1 Flame Extinguishing Time Table

[0076]

[0077]

[0078] Comparing the data from Example 1 and Comparative Example 1, it can be seen that the combined use of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine can enhance the fire extinguishing effect and shorten the extinguishing time. Comparing the data from Comparative Example 1 and Comparative Example 2, it can be seen that the microcapsules in Example 1 extinguish the fire 4 seconds faster than the microcapsules in Comparative Example 2. The microcapsules in Example 1 have a relatively larger particle size, resulting in a higher extinguishing agent content for the same mass. Furthermore, the microcapsule shell is destroyed more quickly, leading to faster core material release and better fire extinguishing performance.

[0079] The fire extinguishing effect in Examples 2-3 is not as good as that in Example 1 because the microcapsules in Comparative Example 1 have a larger particle size. Particle size and shell material density are also important factors affecting the fire extinguishing effect of microcapsules.

[0080] The fire extinguishing microcapsules from Example 1 and Comparative Example 3 were stored at 45°C for one week, and their weight loss was recorded. After one week of storage, the weight loss rate of the fire extinguishing microcapsules in Example 1 was 20%, while that in Comparative Example 3 was 35%. The fire extinguishing microcapsules in Comparative Example 3 were not easily preserved at room temperature, indicating that the fire extinguishing microcapsules of the present invention are easier to preserve at room temperature, and there is no risk of leakage of the core material.

[0081] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A fire extinguishing microcapsule containing cis-hexafluorobutene, characterized in that, The device includes a core and a melamine polymer encapsulating the core. The core is composed of cis-1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine, with a molar ratio of 1,1,1,4,4,4-hexafluoro-2-butene to perfluorotriethylamine of 4-5:

1. The particle size of the fire extinguishing microcapsule is 40 μm to 200 μm, and the fire extinguishing trigger temperature of the fire extinguishing microcapsule is 70 to 110°C.

2. A method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene according to any one of claims 1, characterized in that, Includes the following steps: S1. At 10℃~15℃, 1,1,1,4,4,4-hexafluoro-2-butene and perfluorotriethylamine are added to the emulsifier and stirred to emulsify, thereby obtaining an emulsion containing a core. S2. Add the melamine prepolymer to the emulsion containing the core to obtain the polymerization reaction solution; S3. Add an acidic solution to adjust the pH of the polymerization reaction solution to 3-4, and keep it at this temperature for 5-6 hours to carry out the polymerization reaction; S4. After filtration and drying, the fire extinguishing microcapsules are obtained.

3. The method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene according to claim 2, characterized in that, The emulsifier mentioned in S1 is one or more of styrene-maleic anhydride sodium salt, sodium dodecyl sulfate, and sodium dodecylbenzene sulfonate.

4. The method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene according to claim 2, characterized in that, The stirring speed in S1 is 200 r / min to 1500 r / min, and the emulsification time is 10 min to 20 min.

5. The method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene according to claim 2, characterized in that, The melamine prepolymer is a water-soluble melamine prepolymer, and the melamine prepolymer is one of the following: FN-9010 resin, MF4750 resin from Xinli Chemical, and CYMEL 385 resin.

6. The method for preparing fire extinguishing microcapsules containing cis-hexafluorobutene according to claim 3, characterized in that, The acidic solution is one or more of the following: oxalic acid, citric acid, acetic acid, boric acid, dilute sulfuric acid, dilute hydrochloric acid, dilute nitric acid, and dilute phosphoric acid.

7. An application of a fire extinguishing microcapsule containing cis-hexafluorobutene as described in any one of claims 1, characterized in that, The fire extinguishing microcapsules are used as raw materials in the production of fire blankets, fire extinguishing pads, fire extinguishing coatings, and fire extinguishing fibers.

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