Efficient environment-friendly flame-retardant fire extinguishing agent and preparation method thereof

Abstract

The invention discloses an efficient environment-friendly flame-retardant fire extinguishing agent and a preparation method thereof. The efficient environment-friendly flame-retardant fire extinguishing agent is prepared from the following components in parts by weight: 5 to 10 parts of gelatin, 1 to 2 parts of chitosan, 20 to 40 parts of 2-bromotrifluoropropene (2-BTP), 10 to 15 parts of acetic acid solution, 0.1 to 0.5 part of nonionic emulsifier, 0.05 to 0.2 part of cross-linking agent, 5 to 10 parts of anti-freezing agent and 70 to 120 parts of deionized water. The invention belongs to the technical field of flame-retardant fire extinguishing agents, and particularly relates to an efficient environment-friendly flame-retardant fire extinguishing agent and a preparation method thereof. According to the invention, the nanoscale microcapsule formed by compounding gelatin and chitosan is used as a wall material to effectively encapsulate the volatile liquid 2-bromotrifluoropropene (2-BTP) with efficient fire extinguishing performance, so that the stability and safety of the fire extinguishing agent are remarkably improved, and the application range of the fire extinguishing agent is remarkably widened.

Description

Technical Field

[0001] The present invention belongs to the technical field of flame retardant fire extinguishing agents, and in particular relates to a high-efficiency and environment-friendly flame retardant fire extinguishing agent and a preparation method thereof. Background Art

[0002] Electrical equipment and lithium-ion batteries are widely used in energy storage, electric vehicles, and electronic devices, posing an increasingly significant fire risk. Traditional water-based, dry powder, or halogenated fire extinguishing agents often suffer from issues such as high conductivity, incomplete fire extinguishing, and poor environmental performance. In lithium battery fires, the extinguishing agents often have difficulty penetrating the internal structure, leading to rekindling.

[0003] In recent years, some environmentally friendly fire extinguishing agents such as perfluorohexanone, aerosols, and foams have seen some development in their applications, but they still face issues such as toxicity, cost, or environmental limitations. Therefore, the development of a safe, environmentally friendly, and flame-retardant fire extinguishing agent is of great significance. Summary of the Invention

[0004] To address the challenges of existing liquid fire extinguishing agents, such as volatility, poor compatibility with electrical equipment, the tendency for lithium battery fires to reignite, and poor encapsulation stability, this invention proposes a highly effective and environmentally friendly flame-retardant fire extinguishing agent and its preparation method, aiming to address the technical challenges of balancing high-efficiency fire extinguishing with safety and environmental protection. Specifically, the invention utilizes nanoscale microcapsules composed of gelatin and chitosan as the wall material to effectively encapsulate the highly effective fire-extinguishing volatile liquid 2-bromotrifluoropropene (2-BTP), significantly improving the stability, safety, and applicability of the fire extinguishing agent.

[0005] The technical solution adopted by the present invention is as follows: The present invention proposes a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which includes the following components by weight: 5-10 parts of gelatin, 1-2 parts of chitosan, 20-40 parts of 2-bromotrifluoropropylene (2-BTP), 10-15 parts of acetic acid solution, 0.1-0.5 parts of non-ionic emulsifier, 0.05-0.2 parts of cross-linking agent, 5-10 parts of antifreeze and 80-120 parts of deionized water.

[0006] Furthermore, the gelatin is Type B gelatin.

[0007] Furthermore, the mass concentration of the chitosan is 0.5-1.0 wt%.

[0008] Furthermore, the mass concentration of the acetic acid solution is 0.5wt%

[0009] Furthermore, the emulsifier is Tween 80.

[0010] Furthermore, the cross-linking agent is glutaraldehyde.

[0011] Furthermore, the antifreeze agent is polyethylene glycol 400 (PEG400).

[0012] Furthermore, the electrical conductivity of the high-efficiency and environmentally friendly flame-retardant fire extinguishing agent is less than 10 μS / cm, and is suitable for rapid suppression of fires in electrical equipment and lithium batteries.

[0013] The present invention also provides a preparation process of a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which specifically comprises the following steps:

[0014] (1) Dissolve Type B gelatin in deionized water, heat briefly in a 40°C water bath to dissolve, and cool to 28°C to obtain a gelatin aqueous phase;

[0015] (2) Dissolve chitosan in an aqueous acetic acid solution and adjust the pH to 5.5 to obtain a chitosan aqueous phase;

[0016] (3) 2-Bromotrifluoropropylene (2-BTP) was mixed with Tween 80 and added dropwise to the gelatin aqueous phase, and ultrasonicated at 25°C for 10 minutes to form a nanoemulsion;

[0017] (4) Adding the nanoemulsion to the chitosan aqueous phase to form a composite microcapsule primary shell;

[0018] (5) Add glutaraldehyde to the primary shell of the microcapsule, stir at 25°C for 1 hour, centrifuge at 10,000 rpm for 10 minutes, and disperse in water to obtain a highly efficient and environmentally friendly flame retardant fire extinguishing agent.

[0019] Furthermore, the speed of the ultrasound is 10000-15000 rpm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The Type B gelatin-chitosan double-layer composite structure can complete emulsification and cross-linking under temperature control conditions of <30°C, achieving high-density encapsulation of 2-bromotrifluoropropylene (2-BTP) and significantly reducing volatile losses;

[0022] (2) 2-bromotrifluoropropene (2-BTP) rapidly vaporizes and releases when exposed to fire, and with the cooling and insulation effects of water phase,

[0023] "Fire extinguishing + explosion suppression + cooling" triple synergy;

[0024] (3) Water-based systems can be used in low-temperature environments of -20°C by adding antifreeze;

[0025] (4) The overall system has low electrical conductivity, does not corrode electronic equipment, and uses natural polymers that are non-toxic and biodegradable;

[0026] (5) Use conventional emulsification and cross-linking process, control the temperature to <30℃, the process is safe, the equipment is highly compatible, and it is suitable for pilot scale-up. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Comparison of the average particle size of the microcapsules of Examples 1-3 and Comparative Examples 1-2;

[0028] Figure 2 Comparison of the encapsulation rates of Examples 1-3 and Comparative Examples 1-2;

[0029] Figure 3 The fire extinguishing effects of Examples 1-3 and Comparative Examples 1-2 are compared.

[0030] Figure 4 This is the SEM image of the high-efficiency and environmentally friendly flame retardant fire extinguishing agent of the present invention. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below through specific preferred embodiments, but the present invention is not limited to the following embodiments.

[0032] It should be noted that, unless otherwise specified, all chemical reagents and raw materials used in the present invention were purchased from commercial channels. Type B gelatin (90-100 Bloom) was purchased from Beijing Solebold Technology Co., Ltd.; chitosan (degree of deacetylation ≥ 85%) was purchased from Sinopharm Chemical Reagent Co., Ltd.; 2-bromotrifluoropropylene (2-BTP, 99%) was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.; Tween 80 was purchased from Sigma-Aldrich; glutaraldehyde (analytical grade) was purchased from Tianjin Komiou Chemical Reagent Co., Ltd.; and polyethylene glycol 400 (PEG400) was purchased from Aladdin Reagent.

[0033] Example 1

[0034] The present invention provides a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which comprises the following components in parts by weight: 5 parts of Type B gelatin, 1 part of chitosan, 20 parts of 2-bromotrifluoropropylene (2-BTP), 10 parts of acetic acid solution, 0.1 parts of Tween 800, 0.05 parts of glutaraldehyde, 5 parts of polyethylene glycol 400 (PEG400) and 50 parts of deionized water.

[0035] Wherein, the mass concentration of the chitosan is 0.5wt%.

[0036] Wherein, the mass concentration of the acetic acid solution is 0.5wt%.

[0037] The high-efficiency and environmentally friendly flame-retardant fire extinguishing agent has a conductivity of less than 10 μS / cm and is suitable for rapid suppression of fires in electrical equipment and lithium batteries.

[0038] The present invention also provides a preparation process of a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which specifically comprises the following steps:

[0039] (1) Dissolve 5 parts of Type B gelatin in 20 parts of deionized water, heat briefly in a 40°C water bath to dissolve, and cool to 28°C to obtain a gelatin aqueous phase;

[0040] (2) Dissolve 1 part of chitosan in 10 parts of acetic acid aqueous solution and adjust the pH to 5.5 to obtain a chitosan aqueous phase;

[0041] (3) 20 parts of 2-bromotrifluoropropylene (2-BTP) and 0.1 parts of Tween 80 were mixed and added dropwise to the gelatin aqueous phase, and ultrasonicated at 10,000 rpm for 10 minutes at 25°C to form a nanoemulsion;

[0042] (4) Adding the nanoemulsion to the chitosan aqueous phase to form a composite microcapsule primary shell;

[0043] (5) Add 0.05 parts of glutaraldehyde to the primary shell of the microcapsule, stir at 25°C for 1 hour, centrifuge at 10,000 rpm for 10 minutes, and disperse into 30 parts of water containing 5 parts of PEG400 to obtain a highly efficient and environmentally friendly flame retardant fire extinguishing agent.

[0044] Example 2

[0045] The present invention provides a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which comprises the following components in parts by weight: 7.5 parts of Type B gelatin, 1.5 parts of chitosan, 30 parts of 2-bromotrifluoropropylene (2-BTP), 12.5 parts of acetic acid solution, 0.3 parts of Tween 80, 0.125 parts of glutaraldehyde, 7.5 parts of polyethylene glycol 400 (PEG400), and 95 parts of deionized water.

[0046] Wherein, the mass concentration of the chitosan is 0.5wt%.

[0047] Wherein, the mass concentration of the acetic acid solution is 0.5wt%.

[0048] The high-efficiency and environmentally friendly flame-retardant fire extinguishing agent has a conductivity of less than 10 μS / cm and is suitable for rapid suppression of fires in electrical equipment and lithium batteries.

[0049] The present invention also provides a preparation process of a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which specifically comprises the following steps:

[0050] (1) Dissolve 7.5 parts of Type B gelatin in 20 parts of deionized water, heat briefly in a 40°C water bath to dissolve, and cool to 28°C to obtain a gelatin aqueous phase;

[0051] (2) Dissolve 1.5 parts of chitosan in 12.5 parts of acetic acid aqueous solution and adjust the pH to 5.5 to obtain a chitosan aqueous phase;

[0052] (3) 30 parts of 2-bromotrifluoropropylene (2-BTP) and 0.3 parts of Tween 80 were mixed and added dropwise to the gelatin aqueous phase, and ultrasonicated at 12500 rpm for 10 minutes at 25°C to form a nanoemulsion;

[0053] (4) Adding the nanoemulsion to the chitosan aqueous phase to form a composite microcapsule primary shell;

[0054] (5) Add 0.125 parts of glutaraldehyde to the primary shell of the microcapsule, stir at 25°C for 1 hour, centrifuge at 10,000 rpm for 10 minutes, and disperse in 75 parts of water containing 6.5 parts of PEG400 to obtain a highly efficient and environmentally friendly flame retardant fire extinguishing agent.

[0055] Example 3

[0056] The present invention provides a high-efficiency and environmentally friendly flame retardant fire extinguishing agent, which comprises the following components in parts by weight: 10 parts of Type B gelatin, 2 parts of chitosan, 40 parts of 2-bromotrifluoropropylene (2-BTP), 15 parts of acetic acid solution, 0.5 parts of Tween 80, 0.2 parts of glutaraldehyde, 10 parts of polyethylene glycol 400 (PEG400) and 120 parts of deionized water.

[0057] Wherein, the mass concentration of the chitosan is 0.5wt%.

[0058] Wherein, the mass concentration of the acetic acid solution is 0.5wt%.

[0059] The high-efficiency and environmentally friendly flame-retardant fire extinguishing agent has a conductivity of less than 10 μS / cm and is suitable for rapid suppression of fires in electrical equipment and lithium batteries.

[0060] The present invention also provides a process for preparing a highly efficient and environmentally friendly flame retardant fire extinguishing agent, which specifically comprises the following steps:

[0061] (1) Dissolve 10 parts of Type B gelatin in 20 parts of deionized water, heat briefly in a 40°C water bath to dissolve, and cool to 28°C to obtain a gelatin aqueous phase;

[0062] (2) Dissolve 2 parts of chitosan in 15 parts of acetic acid aqueous solution and adjust the pH to 5.5 to obtain a chitosan aqueous phase;

[0063] (3) 40 parts of 2-bromotrifluoropropylene (2-BTP) and 0.5 parts of Tween 80 were mixed and added dropwise to the gelatin aqueous phase, and ultrasonicated at 15,000 rpm for 10 minutes at 25°C to form a nanoemulsion;

[0064] (4) Adding the nanoemulsion to the chitosan aqueous phase to form a composite microcapsule primary shell;

[0065] (5) Add 0.2 parts of glutaraldehyde to the primary shell of the microcapsule, stir at 25°C for 1 hour, centrifuge at 10000 rpm for 10 minutes, and disperse in 100 parts of water containing 10 parts of PEG400 to obtain a highly efficient and environmentally friendly flame retardant fire extinguishing agent.

[0066] Comparative Example 1

[0067] The difference of this comparative example is that 2-bromotrifluoropropylene (2-BTP) is replaced by an equal amount of deionized water, and the other components and component ratios are the same as those in Example 1.

[0068] Comparative Example 2

[0069] The difference of this comparative example is that no gelatin and chitosan are added, and only 2-bromotrifluoropropylene (2-BTP) and Tween 80 are emulsified in water to form a crude emulsion, that is, no gelatin-chitosan microcapsule encapsulation is performed.

[0070] Performance Testing

[0071] The present invention conducted a performance comparison test on the fire extinguishing agent samples prepared in Examples 1-3 and Comparative Examples 1-2 through the following experiments. The main test indicators include: average particle size of microcapsules, encapsulation rate, low-temperature stability (storage at -20°C for 7 days), fire extinguishing time, re-ignition situation and spray conductivity.

[0072] Table 1: Performance Test

[0073]

[0074] Results show that the samples prepared in Examples 1–3 exhibit excellent microcapsule particle size, encapsulation efficiency, low-temperature storage stability, and fire extinguishing efficiency. They can be stored for long periods at –20°C without precipitation or delamination. In a simulated lithium battery fire test, they extinguished the fire within 5 seconds, with no rekindling within 30 minutes of extinguishing, demonstrating excellent immediate fire suppression performance and long-term safety. In contrast, Comparative Example 1 lacks the core fire extinguishing agent 2-bromotrifluoropropene (2-BTP), exhibiting only a cooling effect and incomplete fire extinguishing. While Comparative Example 2 contains 2-bromotrifluoropropene (2-BTP), it lacks a gelatin-chitosan composite shell, resulting in delamination and leakage at low temperatures, and the possibility of rekindling during fire extinguishing. Furthermore, the gelatin-chitosan composite shell structure itself possesses hydrogel properties, gradually releasing encapsulated water and 2-bromotrifluoropropene (2-BTP) as the fire temperature rises, achieving a synergistic fire extinguishing mechanism combining physical insulation, vapor-phase fire suppression, and delayed cooling. Therefore, the present invention achieves stable fixation and controlled release of the volatile liquid fire extinguishing core material by encapsulating a high-efficiency fire extinguishing agent in a dual-functional natural polymer shell, which not only improves the fire extinguishing efficiency, but also has significant low-temperature adaptability and anti-reignition ability, showing practical engineering application potential in high-risk scenarios such as lithium batteries and electrical equipment.

[0075] It should be noted that, in this document, relational terms such as first and second, etc., are used only 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 "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0076] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

[0077] The present invention and its embodiments are described above. This description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by this and, without departing from the purpose of the present invention, designs structures and embodiments similar to this technical solution without inventiveness, they shall fall within the scope of protection of the present invention.

Claims

1. A highly efficient and environmentally friendly flame retardant fire extinguishing agent, characterized in that: The invention comprises the following components in parts by weight: 5-10 parts of gelatin, 1-2 parts of chitosan, 20-40 parts of 2-bromotrifluoropropylene (2-BTP), 10-15 parts of acetic acid solution, 0.1-0.5 parts of nonionic emulsifier, 0.05-0.2 parts of crosslinking agent, 5-10 parts of antifreeze agent and 70-120 parts of deionized water.

2. A high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 1, characterized in that: The gelatin is Type B gelatin.

3. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 2, characterized in that: The mass concentration of the chitosan is 0.5-1.0 wt%.

4. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 3, characterized in that: The mass concentration of the acetic acid solution is 0.5 wt%.

5. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 4, characterized in that: The emulsifier is Tween 80.

6. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 5, characterized in that: The cross-linking agent is glutaraldehyde.

7. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 6, characterized in that: The antifreeze agent is polyethylene glycol 400 (PEG400).

8. The high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 7, characterized in that: The water-based fire extinguishing agent has a conductivity of less than 10 μS / cm and is suitable for quickly suppressing fires of electrical equipment and lithium batteries.

9. A method for preparing the high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 8, characterized in that: The preparation method comprises the following steps: (1) Dissolve gelatin in deionized water, heat briefly in a 40°C water bath to dissolve, and cool to 28°C to obtain a gelatin aqueous phase; (2) dissolving chitosan in an acetic acid aqueous solution and adjusting the pH to 5.5 to obtain a chitosan aqueous phase; (3) 2-BTP was mixed with an emulsifier and then added dropwise to the gelatin aqueous phase, and ultrasonicated at 25°C for 10 minutes to form a nanoemulsion; (4) adding the nanoemulsion to the chitosan aqueous phase to form a primary shell of the microcapsule; (5) Adding a crosslinking agent into the primary shell of the microcapsule, stirring at 25° C. for 1 hour, centrifuging at 10,000 rpm for 10 minutes, and dispersing into water to obtain a highly efficient and environmentally friendly flame retardant fire extinguishing agent.

10. The method for preparing a high-efficiency and environmentally friendly flame retardant fire extinguishing agent according to claim 9, characterized in that: The speed of the ultrasound is 10000-15000 rpm.

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