High-efficiency environment-friendly foam extinguishing agent and preparation method thereof

Abstract

The application discloses a kind of high-efficiency environmental protection foam extinguishing agent and preparation method thereof, the foam extinguishing agent is composed of the following components by mass percentage: 15-30% silicone surfactant compound system, 0.3-1% biological polymer polysaccharide complex stabilizer, 0.8-1.2% preservative, 1-2% cosolvent, 1-2% chelating agent, the balance is water, the total of each component is 100%.The silicone surfactant compound system is composed of tetrasiloxane surfactant and trisiloxane surfactant.The foam extinguishing agent of the application takes silicone surfactant compound system as the core, can form film on the surface of large oil-filled equipment special oil (transformer oil) quickly, effectively suppresses the fire of large oil-filled equipment of power system;In addition, the foam extinguishing agent does not contain PFOS, and is green and environmental protection.

Description

Technical Field

[0001] This invention relates to the field of foam fire extinguishing agent technology, specifically to a high-efficiency and environmentally friendly foam fire extinguishing agent and its preparation method. Background Technology

[0002] With the expansion of power systems, the fire risk of large oil-filled equipment (such as transformers and reactors) is becoming increasingly prominent. These devices contain large amounts of flammable insulating oil, and leaks or short circuits can easily ignite high-temperature flowing fires, which spread rapidly and have a high risk of reignition. Traditional extinguishing agents (such as fluoroprotein foam and dry powder) suffer from low extinguishing efficiency, poor resistance to reignition, and equipment corrosion. While aqueous fluorinated film-forming foam (AFFF) can quickly spread to form an insulating film, its core component, fluorocarbon surfactants, is difficult to degrade and has high bioaccumulation potential, leading to its complete elimination by the Stockholm Convention. The power industry urgently needs a fluorine-free alternative technology that combines high-efficiency fire extinguishing performance with environmentally friendly characteristics, while also being adaptable to the complex scenarios of oil-filled equipment fires (such as covering high-temperature oil surfaces and suppressing oil vapor reignition). Existing products are insufficient to meet these needs.

[0003] Currently, the research and development of fluorine-free foam fire extinguishing agents mainly focuses on fires involving low-boiling-point flammable liquid fuels. However, the transformer oil used in oil-filled equipment in power systems is a heavy insulating oil with large oil volume, high oil temperature, large fire scale, and complex fire environment, making it difficult to extinguish. Conventional fluorine-free formulations have slow flow rate, poor oil resistance, and short stability time, making them difficult to extinguish fires involving large oil-filled equipment. Summary of the Invention

[0004] The technical problem to be solved by this invention is how to improve the fire extinguishing performance of fire extinguishing agents.

[0005] The present invention solves the above-mentioned technical problems through the following technical means:

[0006] A high-efficiency and environmentally friendly foam fire extinguishing agent is composed of the following components by mass percentage: 15%-30% organosilicon surfactant compound system, 0.3%-1% biopolymer polysaccharide composite stabilizer, 0.8%-1.2% preservative, 1%-2% co-solvent, 1%-2% chelating agent, and the balance being water, with the total of all components being 100%.

[0007] The organosilicon surfactant compound system is composed of a tetrasiloxane surfactant and a trisiloxane surfactant; the tetrasiloxane surfactant is one or two of the tetrasiloxane surfactants shown in the following formulas (1) and (2):

[0008] (1)

[0009] (2).

[0010] Preferably, the mass percentage of the organosilicon surfactant compound system can be 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%; the mass percentage of the biopolymer polysaccharide composite stabilizer can be 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%; the mass percentage of the preservative can be 0.8%, 0.9%, 1%, 1.1%, or 1.2%; the mass percentage of the cosolvent can be 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or 2%; and the mass percentage of the chelating agent can be 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, or 2%.

[0011] Preferably, the mass ratio of the tetrasiloxane surfactant to the trisiloxane surfactant is 5-10:10-20; more preferably, it is one of 5:10, 10:20, or 8:12.

[0012] Preferably, the method for preparing the tetrasiloxane surfactant shown in formula (1) includes the following steps:

[0013] S1. In an organic solvent, tris(trimethylsiloxy)silane is reacted with ethylene oxide in the presence of sodium triphenylmethyl, and after acidification, tris(trimethylsiloxy)silylethyl alcohol is obtained.

[0014] S2. In an organic solvent, using tris(trimethylsiloxy)silylethyl alcohol as a raw material, the reaction is carried out with Jones' reagent to obtain a carboxylic acid intermediate;

[0015] S3. In an organic solvent, using amino polyether alcohol Using bromoacetic acid and anhydrous sodium carbonate as raw materials, an amino polyether carboxylic acid is reacted with sodium hydroxide to obtain amine compounds.

[0016] S4. In an organic solvent, using a carboxylic acid intermediate as a raw material, and using dicyclohexylcarbodiimide DCC as a condensing agent, reacts with an amine compound to obtain the tetrasiloxane surfactant shown in formula (1).

[0017] Preferably, in an organic solvent, trichlorosilane (SiHCl3) is used as a raw material, and trimethylsilanol is used for the reaction, with pyridine used to promote the reaction, to obtain tris(trimethylsiloxy)silane.

[0018] Preferably, the organic solvent in S1 is one or a mixture of two of anhydrous toluene or anhydrous dichloromethane, the organic solvent in S2 is anhydrous acetone, the organic solvent in S3 is N,N-dimethylformamide, and the organic solvent in S4 is anhydrous dichloromethane.

[0019] Preferably, in the reaction process, tris(trimethylsiloxy)silane is mixed with an organic solvent, triphenylmethyl sodium is added first, and the mixture is stirred at 25°C for 2 hours; then ethylene oxide is added, and the mixture is stirred at 60-80°C for 8-10 hours. Then, 5% dilute hydrochloric acid is added to adjust the pH to an acidic environment of 3-4, and the mixture is stirred continuously under acidic conditions for 15-30 minutes until the reaction is complete.

[0020] Preferably, during the reaction, in step S2, tris(trimethylsiloxy)silylethyl alcohol is mixed with an organic solvent at 0°C, Jones reagent is slowly added dropwise, and then the mixture is brought back to room temperature (25°C) and stirred for 12 hours until the reaction is complete.

[0021] Preferably, in the first step of S3, during the preparation of amino polyether carboxylic acid, the amino polyether alcohol is... Mix with an organic solvent, and first slowly add bromoacetic acid in batches under 0°C ice bath conditions; then slowly add anhydrous sodium carbonate (Na2CO3) over 30 minutes; after the addition is complete, remove the ice bath, raise the temperature of the reaction system to 50°C, and stir the reaction at this temperature for 8 hours; the reaction temperature for the second step of preparing amine compounds is 25°C, and the reaction time is 4 hours.

[0022] Preferably, during the reaction, S4 is stirred at 60°C for 12 hours until the reaction is complete.

[0023] Preferably, in the preparation method of the tetrasiloxane surfactant shown in formula (1), in S1, the mass ratio of tris(trimethylsiloxy)silane, triphenylmethyl sodium, and ethylene oxide is 25:0.05:3; and the mass ratio of tris(trimethylsiloxy)silane to organic solvent is 25:100.

[0024] In S2, the mass ratio of tris(trimethylsiloxy)silylethyl alcohol to Jones reagent is 30:21.6; the mass ratio of tris(trimethylsiloxy)silylethyl alcohol to organic solvent is 30:100.

[0025] In S3, the mass ratio of amino polyether alcohol to bromoacetic acid is 10.5:7; the mass ratio of amino polyether alcohol to anhydrous sodium carbonate is 10.5:8; and the molar ratio of amino polyether carboxylic acid to sodium hydroxide is 45g:46mmol.

[0026] In S4, the mass ratio of the carboxylic acid intermediate to the amine compound is 10:5; the mass ratio of the carboxylic acid intermediate to dicyclohexylcarbodiimide is 10:6; and the mass ratio of the carboxylic acid intermediate to the organic solvent is 10:80.

[0027] Preferably, the amino polyether alcohol The preparation method includes the following steps:

[0028] S1. Using aziridine and Boc2O as raw materials, Boc-aziridine is reacted in an organic solvent to obtain Boc-aziridine.

[0029] S2. Dissolve Boc-azacyclopropane in a solvent, then add 2-bromoethanol and anhydrous sodium carbonate to react and obtain the intermediate product BocNH(CH2)2O(CH2)2Br.

[0030] S3. Dissolve Boc-NH(CH2)2O(CH2)2Br in a solvent, then add 2-bromoethanol and sodium carbonate to react and obtain the intermediate product BocNH(CH2CH2O)3(CH2)2Br.

[0031] S4. Dissolve BocNH(CH2CH2O)3(CH2)2Br in a solvent, then add trifluoroacetic acid (TFA) to react, and then add NaOH aqueous solution to react to obtain the target product amino polyether alcohol.

[0032] Preferably, the amino polyether alcohol The preparation method includes the following steps:

[0033] S1. Dissolve aziridine and Boc2O in anhydrous dichloromethane, stir at 0°C for 1 hour, then heat to 25°C and continue stirring for 4 hours to obtain Boc-aziridine.

[0034] S2. Dissolve Boc-azacyclopropane in DMF, then add 2-bromoethanol and anhydrous sodium carbonate, and stir at 80°C for 10 hours to obtain the intermediate product BocNH(CH2)2O(CH2)2Br.

[0035] S3. Dissolve Boc-NH(CH2)2O(CH2)2Br in DMF, then add 2-bromoethanol and sodium carbonate, and stir at 80°C for 10 hours to obtain the intermediate product BocNH(CH2CH2O)3(CH2)2Br.

[0036] S4. Dissolve BocNH(CH2CH2O)3(CH2)2Br in anhydrous dichloromethane, then add trifluoroacetic acid (TFA) and stir at 25°C for 6 hours; then add NaOH aqueous solution, heat the system to 70°C, and stir under reflux for 6 hours to obtain the target product, amino polyether alcohol.

[0037] Preferably, in amino polyether alcohol In the preparation method, in S1, the mass ratio of aziridine to Boc₂O is 10:60.8; the mass ratio of aziridine to solvent is 10g:200mL; in S2, the mass ratio of Boc-aziridine to solvent is 33.3g:150mL; the mass ratio of Boc-aziridine, 2-bromoethanol, and anhydrous sodium carbonate is 33.3:29.1:37; in S3, the mass ratio of Boc-NH(CH₂)₂O(CH₂)₂Br to solvent is 62.3g:150mL; Boc-NH The mass ratio of (CH2)2O(CH2)2Br, 2-bromoethanol, and sodium carbonate is 62.3:29.1:37; in S4, the volume ratio of BocNH(CH2CH2O)3(CH2)2Br to solvent is 72.6 g:150 mL; the volume ratio of BocNH(CH2CH2O)3(CH2)2Br to trifluoroacetic acid is 72.6 g:88.4 mL; and the volume ratio of BocNH(CH2CH2O)3(CH2)2Br to NaOH is 72.6 g:232 mmol.

[0038] Preferably, the preparation method of the tetrasiloxane surfactant shown in formula (2) includes the following steps:

[0039] S1. In an organic solvent, tris(trimethylsiloxy)silane is reacted with ethylene oxide in the presence of sodium triphenylmethyl to obtain a sodium alkoxide intermediate.

[0040] S2. In an organic solvent, using sodium alkoxide intermediate as raw material, sodium 3-bromopropane sulfonate is reacted to obtain the tetrasiloxane surfactant shown in formula (2).

[0041] Preferably, in the preparation method of the tetrasiloxane surfactant shown in formula (2), the organic solvent in S1 is one or a mixture of two of anhydrous toluene or anhydrous dichloromethane, and the organic solvent in S2 is one or a mixture of two of anhydrous dichloromethane or anhydrous acetonitrile.

[0042] Preferably, in the preparation method of the tetrasiloxane surfactant shown in formula (2), in the reaction process, tris(trimethylsiloxy)silane is mixed with an organic solvent, triphenylmethyl sodium is added, and the mixture is stirred at 25°C for 2 hours; then ethylene oxide is added, and the mixture is stirred at 60-80°C for 8-10 hours.

[0043] Preferably, in the preparation method of the tetrasiloxane surfactant shown in formula (2), S2 is stirred at 60-80°C for 12-18 hours until the reaction is completed.

[0044] Preferably, in the preparation method of the tetrasiloxane surfactant shown in formula (2), in S1, the mass ratio of tris(trimethylsiloxy)silane, triphenylmethyl sodium, and ethylene oxide is 25:0.05:12; the mass ratio of tris(trimethylsiloxy)silane to organic solvent is 25:100; in S2, the mass ratio of sodium alkoxide intermediate to sodium 3-bromopropanesulfonate is 20:10; the mass ratio of sodium alkoxide intermediate to organic solvent is 20:80.

[0045] Preferably, the trisiloxane surfactant is one or more of vinylsilane, epoxysilane, aminosilane, and ureosilane.

[0046] Preferably, the vinyl silane is one or more of vinyltriethoxysilane surfactant A-151NT, vinyltri(2-methoxyethoxy)silane surfactant Crosile-172, and vinyltrimethoxysilane surfactant SF-Y171; the epoxy silane is epoxy silane surfactant SILQUEST. One or more of the following surfactants are selected: A-186, 3-glycidyl etheroxypropylmethyldiethoxysilane surfactant WETLINK78, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane surfactant COATOSIL-11170; the aminosilane is one or more of the following surfactants: bis-(γ-triethoxysilylpropyl)-amine surfactant Y-11699, bis-(3-(triethoxysilyl)-propyl)-amine surfactant A-1170, and 3-aminopropyltriethoxysilane KBE-90; the ureosilane is one or more of the following surfactants: γ-ureapropyltrimethoxysilane surfactant A-1524, γ-ureapropyltrialkoxysilane surfactant A-1160, and ureapropyltrimethoxysilane surfactant XH-1524.

[0047] Preferably, the biopolymer polysaccharide composite stabilizer is composed of thickening biopolymer polysaccharides and interface-stabilizing biopolymer polysaccharides.

[0048] Preferably, the mass ratio of the thickening biopolymer polysaccharide to the interface-stabilizing biopolymer polysaccharide is 0.1-0.5:0.2-0.5.

[0049] Preferably, the thickening biopolymer polysaccharide is one or more of xanthan gum, guar gum, tamarind gum, and guar gum.

[0050] Preferably, the interface-stabilized biopolymer polysaccharide is one or more of peppermint seed gum, chitosan, gum arabic, and soybean polysaccharides.

[0051] Preferably, the preservative is one or a mixture of two of potassium sorbate and isothiazolinone.

[0052] Preferably, the co-solvent is one or more of urea, formamide, sodium xylenesulfonate, and propylene glycol phenyl ether.

[0053] Preferably, the chelating agent is sodium ethylenediaminetetraacetate.

[0054] The present invention also proposes a method for preparing the aforementioned high-efficiency and environmentally friendly foam fire extinguishing agent, comprising the following steps: uniformly mixing an organosilicon surfactant compound system, a biopolymer polysaccharide composite stabilizer, a preservative, a cosolvent, a chelating agent, and water to obtain the aforementioned high-efficiency and environmentally friendly foam fire extinguishing agent.

[0055] Preferably, the preparation method of the high-efficiency and environmentally friendly foam fire extinguishing agent includes the following steps: adding a co-solvent to water and stirring until completely transparent to obtain pretreated water; taking two portions of the pretreated water and adding tetrasiloxane surfactant and trisiloxane surfactant respectively to prepare tetrasiloxane surfactant solution and trisiloxane surfactant solution respectively, and then mixing them to obtain an organosilicon surfactant compound system solution; taking a portion of the pretreated water and adding thickening biopolymer polysaccharide and chelating agent in sequence to prepare a preemulsion; adding the preemulsion to the organosilicon surfactant compound system solution, and then adding interface-stabilizing biopolymer polysaccharide, preservative and the remaining pretreated water in sequence and mixing evenly to obtain the high-efficiency and environmentally friendly foam fire extinguishing agent.

[0056] Preferably, the preparation method of the high-efficiency and environmentally friendly foam fire extinguishing agent includes the following steps:

[0057] S1. Water pretreatment: Add a co-solvent to water and stir until completely transparent to obtain pretreated water;

[0058] S2. Preparation of organosilicon surfactant complex system solution: Take a portion of pretreated water, add tetrasiloxane surfactant, and stir to obtain tetrasiloxane surfactant solution; take a portion of pretreated water, add trisiloxane surfactant, and stir to obtain trisiloxane surfactant solution; add trisiloxane surfactant solution to tetrasiloxane surfactant solution and stir to obtain organosilicon surfactant complex system solution.

[0059] S3. Add biopolymer polysaccharide composite stabilizer: Take a portion of the pretreated water, add thickening biopolymer polysaccharide and chelating agent in sequence, prepare a pre-emulsion under stirring conditions, add to the organosilicon surfactant compound system solution and stir, add interface-stabilizing biopolymer polysaccharide and stir.

[0060] S4. Add preservative: Add preservative under stirring conditions, and add the remaining pretreated water. After stirring, the high-efficiency and environmentally friendly foam fire extinguishing agent is obtained.

[0061] If dispersed simultaneously, the trisiloxane surfactant will preferentially occupy the interface due to its faster diffusion rate, inhibiting the adsorption of tetrasiloxane. Therefore, the two surfactants must be prepared separately first, and then compounded.

[0062] Preferably, in S1, the stirring speed is 300 rpm and the time is 10 min; in S2, the stirring speed is 500-1000 rpm and the time is 10-20 min; in S3, the stirring speed is 1500 rpm and the time is 15-20 min; and in S4, the stirring speed is 1000 rpm and the time is 10-25 min.

[0063] This invention also proposes the application of the aforementioned high-efficiency and environmentally friendly foam fire extinguishing agent in fire extinguishing of oil-filled equipment in power systems.

[0064] The present invention also proposes a fire extinguishing device containing the aforementioned high-efficiency and environmentally friendly foam fire extinguishing agent.

[0065] The advantages of this invention are:

[0066] (1) Based on the self-synthesized tetrasiloxane surfactant, this invention develops an environmentally friendly foam extinguishing agent formula to address the technical bottleneck of existing fluorine-free foam extinguishing agents being unable to extinguish fires in large oil-filled equipment. The product fully complies with the requirements of the national standard GB15308-2006 "Foam Extinguishing Agents" and has good foam performance and fire extinguishing performance.

[0067] (2) For transformer oil fires, the high-efficiency and environmentally friendly foam extinguishing agent of this invention has excellent foaming performance, foam stability, fire extinguishing performance and film-forming performance. Its foaming ratio is 7-9 times; the 25% liquid separation time is 13-15 min; the fire extinguishing time is 57s-95s; the fire resistance time is 12min-17s-14min-32s; and the film-forming speed is 1.5-2.3cm. 2 / s. Under the same conditions, compared with commercial 3% aqueous film-forming foam extinguishing agent, the foaming ratio is increased by 19.05%-53.06%, the liquid separation time of 25% is extended by 262.79%-318.60%, the extinguishing time is shortened by 51.53%-70.92%, the anti-burning time is extended by 32.32%-56.55%, and the film-forming speed is increased by 25.00%-91.67%.

[0068] (3) This invention does not use any PFOS-like substances. The invented foam fire extinguishing agent has excellent biodegradability, with a biodegradability rate of ≥97% after 28 days.

[0069] (4) This invention has developed a new process for the efficient synthesis of tetrasiloxane surfactants with a simple route and mild conditions.

[0070] (5) The present invention establishes a simple process for preparing foam extinguishing agent stock solution with mild conditions and good repeatability. The prepared foam extinguishing agent stock solution is uniform and stable after standing for 180 days, without stratification or changes in properties. Attached Figure Description

[0071] Figure 1 The results of performance tests of foam fire extinguishing agents at different concentrations of tetrasiloxane surfactant (1);

[0072] Figure 2 The results of performance tests of foam fire extinguishing agents at different concentrations of tetrasiloxane surfactant (2);

[0073] Figure 3 The results of performance tests on foam fire extinguishing agents at different concentrations of trisiloxane surfactants are presented.

[0074] Figure 4 The results of performance tests on foam fire extinguishing agents at different stabilizer concentrations;

[0075] Figure 5 This is a static image of the foam extinguishing agent stock solution prepared in Example 1 of the present invention.

[0076] Figure 6 This is a static image of the foam fire extinguishing agent stock solution prepared in Comparative Example 7 of this invention.

[0077] Figure 7 These are images showing the film-forming phenomena of the foam fire extinguishing agents prepared in Examples 1-4 and Comparative Examples 3 and 6 of this invention, and 3% AFFF.

[0078] Figure 8 These are diagrams illustrating the fire extinguishing phenomena of the foam fire extinguishing agents prepared in Examples 1-4 of this invention.

[0079] Figure 9 The images show the fire extinguishing phenomena of the foam fire extinguishing agents prepared in Comparative Examples 1-6 of this invention and 3% AFFF.

[0080] Figure 10 The figures show the test data of the foam fire extinguishing agents and the film-forming properties of 3% AFFF prepared in Examples 1-4 and Comparative Examples 3, 5 and 6 of this invention. Detailed Implementation

[0081] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0082] Unless otherwise specified, all test materials and reagents used in the following examples are commercially available.

[0083] Unless otherwise specified in the embodiments, any techniques or conditions described in the literature in this field or in accordance with the product manual may be followed.

[0084] A high-efficiency and environmentally friendly foam fire extinguishing agent is composed of the following components by mass percentage: 15%-30% organosilicon surfactant compound system, 0.3%-1% biopolymer polysaccharide composite stabilizer, 0.8%-1.2% preservative, 1%-2% cosolvent, 1%-2% chelating agent, and the balance being water, with the total of all components being 100%; wherein, the organosilicon surfactant compound system is composed of tetrasiloxane surfactant and trisiloxane surfactant;

[0085] According to the standard GB 15308-2006 "Foam Extinguishing Agents", the effects of different concentrations of key components such as tetrasiloxane surfactant, trisiloxane surfactant and stabilizer on the diffusion coefficient, foaming ratio, 25% liquid separation time, extinguishing time and anti-burning time of the high-efficiency and environmentally friendly foam extinguishing agent formulation were tested. The structural formula and preparation method of tetrasiloxane surfactant (1) are shown in Example 1; the structural formula and preparation method of tetrasiloxane surfactant (2) are shown in Example 2.

[0086] The foam extinguishing agent formulation with fixed mass concentrations of all substances except tetrasiloxane surfactant (1) was as follows: 1%-12% tetrasiloxane surfactant (1), 12% trisiloxane surfactant A-151NT, 0.2% xanthan gum, 0.3% chitosan, 1.2% potassium sorbate, 2% urea, 2% sodium ethylenediaminetetraacetate, and the balance being water. Based on this formulation, the performance of the foam extinguishing agent at different concentrations of tetrasiloxane surfactant (1) was tested, such as... Figure 1As shown. When the concentration of tetrasiloxane surfactant (1) is below 5%, the foam extinguishing agent has a large foaming ratio, but a small diffusion coefficient, short 25% exudation time and short anti-burning time, and a long extinguishing time. When the concentration of tetrasiloxane surfactant (1) is above 8%, the foam extinguishing agent has a large foaming ratio and diffusion coefficient, and a short extinguishing time, but a short 25% exudation time and short anti-burning time. When the concentration of tetrasiloxane surfactant (1) is between 5% and 8%, the foam extinguishing agent has a large foaming ratio and diffusion coefficient, a long 25% exudation time and long anti-burning time, and a short extinguishing time, resulting in the best overall performance of the foam extinguishing agent. Therefore, the optimal concentration range of tetrasiloxane surfactant (1) is 5%-8%.

[0087] The foam extinguishing agent formulation with fixed mass concentrations of all substances except tetrasiloxane surfactant (2) was as follows: 1%-14% tetrasiloxane surfactant (2), 12% trisiloxane surfactant A-151NT, 0.2% xanthan gum, 0.3% chitosan, 1.2% potassium sorbate, 2% urea, 2% sodium ethylenediaminetetraacetate, and the balance being water. Based on this formulation, the performance of the foam extinguishing agent at different concentrations of tetrasiloxane surfactant (2) was tested, such as... Figure 2 As shown. When the concentration of tetrasiloxane surfactant (2) is below 5%, the foam extinguishing agent has a large foaming ratio, but a small diffusion coefficient, a short 25% exudation time, a short anti-burning time, and a long extinguishing time. When the concentration of tetrasiloxane surfactant (2) is above 10%, the foam extinguishing agent has a large foaming ratio and a large diffusion coefficient, but a short 25% exudation time, a short anti-burning time, and a long extinguishing time. When the concentration of tetrasiloxane surfactant (2) is between 5% and 10%, the foam extinguishing agent has a large foaming ratio and a large diffusion coefficient, a long 25% exudation time, a long anti-burning time, and a short extinguishing time, resulting in the best overall performance of the foam extinguishing agent. Therefore, the optimal concentration range of tetrasiloxane surfactant (2) is 5%-10%.

[0088] The foam extinguishing agent formulation with fixed mass concentrations of substances other than the trisiloxane surfactant was as follows: 8% tetrasiloxane surfactant (2), 3%-25% trisiloxane surfactant A-151NT, 0.2% xanthan gum, 0.3% chitosan, 1.2% potassium sorbate, 2% urea, 2% sodium ethylenediaminetetraacetate, and the balance being water. Based on this formulation, the performance of the foam extinguishing agent at different concentrations of trisiloxane surfactant was tested, such as... Figure 3As shown in the diagram, when the concentration of trisiloxane surfactant is below 10%, the foam extinguishing agent has a large expansion ratio, but a small diffusion coefficient, short 25% exudation time, short anti-burning time, and long extinguishing time. When the concentration of trisiloxane surfactant is above 20%, the foam extinguishing agent has a large expansion ratio and diffusion coefficient, and a short extinguishing time, but a short 25% exudation time and short anti-burning time. When the concentration of trisiloxane surfactant is between 10% and 20%, the foam extinguishing agent has a large expansion ratio and diffusion coefficient, a long 25% exudation time and long anti-burning time, and a short extinguishing time, exhibiting the best overall performance. Therefore, the optimal concentration range for trisiloxane surfactant is 10%-20%.

[0089] The foam extinguishing agent formulation with fixed mass concentrations of substances other than the stabilizer is as follows: 7% tetrasiloxane surfactant (1), 12% trisiloxane surfactant A-151NT, 0.1%-1.5% biopolymer polysaccharide composite stabilizer (a mixture of xanthan gum and chitosan in a mass ratio of 2:3), 1.2% potassium sorbate, 2% urea, 2% sodium ethylenediaminetetraacetate, and the balance being water. Based on this formulation, the performance of the foam extinguishing agent at different stabilizer concentrations was tested, such as... Figure 4 As shown in the diagram, when the stabilizer concentration is below 0.3%, the foam extinguishing agent has a larger foaming ratio and diffusion coefficient, but its 25% exudation time and anti-burning time are short, while its extinguishing time is long. When the stabilizer concentration is above 1%, the foam extinguishing agent has a large diffusion coefficient, but its 25% exudation time and anti-burning time are short, while its extinguishing time is long. When the stabilizer concentration is between 0.3% and 1%, the foam extinguishing agent has a larger foaming ratio and diffusion coefficient, a longer 25% exudation time and anti-burning time, and a shorter extinguishing time, exhibiting the best overall performance. Therefore, the optimal concentration range for the stabilizer is 0.3%-1%.

[0090] Therefore, based on this highly efficient and environmentally friendly foam fire extinguishing agent formula and Figure 1-4 The test results and design examples 1-4 are as follows:

[0091] Example 1

[0092] Prepare a high-efficiency and environmentally friendly foam fire extinguishing agent using the following method:

[0093] ① First, weigh out 5g of tetrasiloxane surfactant (1), 10g of trisiloxane surfactant vinylsilane surfactant A-151NT, 0.1g of xanthan gum, 0.2g of peppermint seed gum, 0.8g of potassium sorbate, 1g of urea, and 1g of sodium ethylenediaminetetraacetate; ② Add 1g of urea to 81.9g of deionized water and stir at 300rpm for 10min until completely transparent to obtain pretreated deionized water; ③ Add 5g of tetrasiloxane surfactant (1) to 10g of pretreated deionized water and stir at 800rpm for 15min to obtain a tetrasiloxane surfactant solution; Add 10g of trisiloxane surfactant vinylsilane surfactant A-151NT to 10g of pretreated deionized water and stir at 500rpm for 20min to obtain a vinylsilane surfactant solution; Then add the vinylsilane surfactant solution to the tetrasiloxane surfactant solution and stir at 1000rpm for 10min to obtain a surfactant compound system. ④ Add 0.1g xanthan gum and 1g sodium EDTA to 10g pretreated deionized water sequentially. Stir at 1500rpm and 40℃ for 20min to obtain a preemulsion. Then, add the preemulsion to the surfactant compound system at 1500rpm and stir for 15min. Next, add 0.2g peppermint seed gum at 1500rpm and stir for 15min. Finally, add 0.8g potassium sorbate at 1000rpm and replenish the remaining pretreated deionized water. Stir for 20min to obtain the foam extinguishing agent stock solution. Its appearance is shown in the image below. Figure 5 As shown in the figure, after 180 days of natural settling, the appearance of the original solution changed little, remaining a pale yellow homogeneous liquid without obvious stratification or precipitation, indicating that the original solution has good stability.

[0094] The structural formula and synthesis process of the tetrasiloxane surfactant (1) are as follows:

[0095]

[0096]

[0097] The specific synthesis path is as follows:

[0098] Step 1: Synthesis of tris(trimethylsiloxy)silane

[0099] Under nitrogen protection and at 3°C, 15 g of trichlorosilane (SiHCl3) was dissolved in 60 g of anhydrous n-hexane. Then, 30 g of pyridine was added all at once, followed by the slow addition of 30 g of trimethylsilanol with stirring. After the addition was complete, the mixture was stirred for another 3 hours. Subsequently, the system was heated to 50°C and stirred for another 0.8 hours to ensure complete reaction. Byproducts were removed by vacuum distillation to obtain tris(trimethylsiloxy)silane.

[0100]

[0101] Step 2: Reaction with ethylene oxide

[0102] At 25°C, 25g of tris(trimethylsiloxy)silane was dissolved in 100g of anhydrous toluene, and 0.05g of triphenylmethyl sodium was slowly added. After stirring for 2 hours, 3g of ethylene oxide was added, and the mixture was heated to 60°C to carry out the epoxide ring-opening reaction. After stirring for 8 hours, Si-H reacted with ethylene oxide to form a sodium alkoxide intermediate. Then, an appropriate amount of 5% dilute hydrochloric acid was added to adjust the pH to 4 to create an acidic environment. The mixture was stirred continuously under acidic conditions for 30 minutes until the reaction was complete to obtain tris(trimethylsiloxy)silylethyl alcohol.

[0103]

[0104] Step 3: Hydroxyl oxidation reaction

[0105] At 0°C, 30g of tris(trimethylsiloxy)silylethyl alcohol was dissolved in 100g of anhydrous acetone, and 80g of Jones reagent with a mass concentration of 27% was slowly added. After the addition was completed, the temperature was restored to 25°C, and the reaction was carried out for 12 hours to obtain a carboxylic acid intermediate.

[0106]

[0107] Step 4: Carboxylic acid amination

[0108] 10g of a carboxylic acid intermediate was dissolved in 80g of anhydrous dichloromethane, followed by the addition of 5g of an amine compound. 6 g of dicyclohexylcarbodiimide (DCC) was added, and the mixture was reacted at 60 °C for 12 hours. The carboxyl and amino fragments were then coupled to obtain the final product. The NMR data are as follows:

[0109] 13 C NMR (100 MHz, CDCl3) δ 180.2, 169.1, 70.7, 70.4, 70.3, 69.2, 65.2,39.9, 23.7, 1.7.

[0110] 1H NMR (400 MHz, CDCl3) δ 8.01 (s, 1H), 3.90 (s, 2H), 3.58-3.71 (m,12H), .3.49 (t, J = 6.1 Hz, 2H), 3.46 (t, J = 6.1 Hz, 2H), 2.63 (s, 2H), 0.06(s, 27H).

[0111] The process is as follows:

[0112]

[0113] Among them, amine compounds The synthesis path is as follows:

[0114]

[0115] The specific synthesis path is as follows:

[0116] Step 1: Nucleophilic substitution reaction

[0117] Under nitrogen protection and at 25°C, 10.5g of amino polyether alcohol was... Dissolve in 200 mL of anhydrous N,N-dimethylformamide. Then, under 0°C ice bath conditions, slowly add 7 g of bromoacetic acid in portions; then, over 30 minutes, slowly add 8 g of anhydrous sodium carbonate (Na₂CO₃). After the addition is complete, remove the ice bath, heat the reaction system to 50°C, and stir the reaction at this temperature for 8 hours to obtain the target product, aminopolyether carboxylic acid.

[0118]

[0119] Step 2: Carboxylic acid alkalization reaction

[0120] 45g of aminopolyether carboxylic acid was dissolved in 150mL of deionized water and stirred at 25°C until a clear solution was formed. Then, 23mL of a 2mol / L sodium hydroxide aqueous solution was slowly added dropwise under an ice-water bath at 0°C. After the addition was complete, the ice bath was removed, the reaction system was heated to 25°C, and the reaction was stirred at this temperature for 4 hours to obtain the target product, an amine compound (sodium aminopolyether carboxylic acid).

[0121]

[0122] The synthetic route for amino polyether alcohols is as follows:

[0123]

[0124] The specific synthesis path is as follows:

[0125] Step 1: Reaction with Boc2O

[0126] 10 g of aziridine and 60.8 g of Boc2O were dissolved in 200 mL of anhydrous dichloromethane. The mixture was stirred at 0 °C for 1 hour, then heated to 25 °C and stirred for another 4 hours to obtain the target product Boc-aziridine.

[0127]

[0128] Step 2: Nucleophilic substitution reaction

[0129] SN1: 33.3 g of Boc-azacyclopropane was dissolved in 150 mL of DMF, then 29.1 g of 2-bromoethanol and 37 g of anhydrous sodium carbonate were added, and the mixture was stirred at 80 °C for 10 hours to obtain the intermediate product BocNH(CH2)2O(CH2)2Br.

[0130]

[0131] SN2: Dissolve 62.3 g of Boc-NH(CH2)2O(CH2)2Br in 150 mL of DMF, then add 29.1 g of 2-bromoethanol and 37 g of sodium carbonate, and stir at 80 °C for 10 hours to obtain the intermediate product BocNH(CH2CH2O)3(CH2)2Br.

[0132]

[0133] Step 3: Boc deprotection and terminal bromine hydrolysis tandem reaction

[0134] 72.6 g of BocNH(CH2CH2O)3(CH2)2Br was dissolved in 150 mL of anhydrous dichloromethane, and then 88.4 mL of trifluoroacetic acid (TFA) was added. The mixture was stirred at 25 °C for 6 hours. Then, 116 mL of 2 mol / L NaOH aqueous solution was added, and the system was heated to 70 °C and stirred under reflux for 6 hours to obtain the target product, amino polyether alcohol.

[0135]

[0136] Example 2

[0137] Prepare a high-efficiency and environmentally friendly foam fire extinguishing agent using the following method:

[0138] ① First, weigh out 10g of tetrasiloxane surfactant (2), 20g of trisiloxane surfactant epoxysilane SILQUEST A-186, 0.5g of tamarind gum, 0.5g of gum arabic, 1.2g of isothiazolinone, 2g of formamide, and 2g of sodium ethylenediaminetetraacetate; ② Add 2g of formamide to 63.8g of deionized water and stir at 300rpm for 10min until completely transparent to obtain pretreated deionized water; ③ Add 10g of tetrasiloxane surfactant (2) to 10g of pretreated deionized water and stir at 800rpm for 15min to obtain a tetrasiloxane surfactant solution; Add 20g of trisiloxane surfactant epoxysilane SILQUEST A-186 to the solution. Add A-186 to 20g of pretreated deionized water and stir at 500rpm for 20min to obtain an epoxy silane surfactant solution; then add the epoxy silane surfactant solution to the tetrasiloxane surfactant solution and stir at 1000rpm for 10min to obtain a surfactant compound system. ④ Add 0.5g of tamarind gum and 2g of sodium ethylenediaminetetraacetate to 10g of pretreated deionized water sequentially and stir at 1500rpm at 40℃ for 20min to obtain a preemulsion; then add the preemulsion to the surfactant compound system at 1500rpm and stir for 15min; then add 0.5g of gum arabic at 1500rpm and stir for 15min; then add 1.2g of isothiazolinone at 1000rpm and replenish the remaining pretreated deionized water, stir for 20min to obtain the foam extinguishing agent stock solution.

[0139] The structural formula and synthesis process of the tetrasiloxane surfactant (2) are as follows:

[0140]

[0141]

[0142] The specific synthesis path is as follows:

[0143] Step 1: Synthesis of tris(trimethylsiloxy)silane. The reaction in step 1 is the same as in Example 1, tetrasiloxane surfactant (1), step 1 synthesis route.

[0144] Step 2: Reaction with ethylene oxide. At 25°C, 25g of tris(trimethylsiloxy)silane was dissolved in 100g of anhydrous toluene, and 0.05g of triphenylmethyl sodium was slowly added. After stirring for 2 hours, 12g of ethylene oxide was added, and the mixture was heated to 80°C to initiate an epoxide ring-opening reaction. The mixture was stirred for 10 hours to allow Si-H to undergo an addition reaction with ethylene oxide, generating a sodium alkoxide intermediate.

[0145]

[0146] Step 3: Introduce sodium sulfonate. Add 20g of sodium alkoxide intermediate to 80g of anhydrous acetonitrile, slowly add 10g of 3-bromopropane sulfonate, heat to 70℃, and stir for 12 hours until the reaction is complete to obtain the target product, tetrasiloxane surfactant (2). Its NMR data are as follows:

[0147] 13 C NMR (100 MHz, CDCl3) δ 70.9, 70.7, 70.2, 66.2, 51.4, 29.4, 15.8,1.7.

[0148] 1 H NMR (400 MHz, CDCl3) δ 3.58-3.71 (m, 12H), 3.52 (t, J = 6.5 Hz, 2H), 3.38 (t, J = 4.3 Hz, 2H), 3.33 (t, J = 6.2 Hz, 2H), 2.12 (tt, J = 6.2, 4.3 Hz, 2H), 1.43 (t, J = 6.5 Hz, 2H), 0.06 (s, 27H).

[0149] The process is as follows:

[0150]

[0151] Example 3

[0152] Prepare a high-efficiency and environmentally friendly foam fire extinguishing agent using the following method:

[0153] ① First, weigh out 8g of tetrasiloxane surfactant (2), 12g of bis-(γ-triethoxysilylpropyl)amine surfactant Y-11699, 0.2g of xanthan gum, 0.3g of chitosan, 1g of isothiazolinone, 1.5g of urea, and 1.5g of sodium ethylenediaminetetraacetate; ② Add 1.5g of urea to 75.5g of deionized water, and stir at 300rpm for 10min until completely transparent to obtain pretreated deionized water; ③ Add 8g of tetrasiloxane surfactant (2) to 10g of sodium ethylenediaminetetraacetate. A tetrasiloxane surfactant solution was prepared by stirring 12g of bis-(γ-triethoxysilylpropyl)amine surfactant Y-11699 in 15g of pretreated deionized water at 800 rpm for 15 min. A trisiloxane solution was prepared by stirring 12g of bis-(γ-triethoxysilylpropyl)amine surfactant Y-11699 in 15g of pretreated deionized water at 500 rpm for 20 min. The trisiloxane solution was then added to the tetrasiloxane surfactant solution and stirred 1000 rpm for 10 min to obtain a surfactant complex system. ④ Add 0.2g xanthan gum and 1.5g sodium EDTA to 10g pretreated deionized water in sequence. Stir at 1500rpm and 40℃ for 20min to obtain a preemulsion. Then, add the preemulsion to the surfactant compound system at 1500rpm and stir for 15min. Next, add 0.3g chitosan at 1500rpm and stir for 15min. Finally, add 1g isothiazolinone at 1000rpm and replenish the remaining pretreated deionized water. Stir for 20min to obtain the foam fire extinguishing agent stock solution.

[0154] The method for synthesizing the tetrasiloxane surfactant (2) is the same as that described in Example 2.

[0155] Example 4

[0156] Same as Example 1, except that the tetrasiloxane surfactant (1) is replaced with tetrasiloxane surfactant (2).

[0157] Comparative Example 1

[0158] Same as Example 1, except that the tetrasiloxane surfactant (1) is replaced with the trisiloxane surfactant COATOSIL-77.

[0159] Comparative Example 2

[0160] Same as Example 2, except that the tetrasiloxane surfactant (2) is replaced with hydrocarbon surfactant AES.

[0161] Comparative Example 3

[0162] Same as Example 1, except that the amount of tetrasiloxane surfactant (1) used is changed from 5g to 1g, and the amount of deionized water in ② is changed from 81.9g to 85.9g.

[0163] Comparative Example 4

[0164] Same as Example 3, except that only the tetrasiloxane surfactant (2) is removed, and the amount of deionized water is changed from 75.5g to 83.5g.

[0165] Comparative Example 5

[0166] Same as Example 4, except that the amount of tetrasiloxane surfactant (2) used is changed from 5g to 1g, and the amount of deionized water is changed from 81.9g to 85.9g.

[0167] Comparative Example 6

[0168] Same as Example 2, except that the amount of tetrasiloxane surfactant (2) used was changed from 10g to 1g, and the amount of deionized water was changed from 63.8g to 72.8g.

[0169] Comparative Example 7

[0170] ① First, weigh out 8g of tetrasiloxane surfactant (2), 12g of bis-(γ-triethoxysilylpropyl)-amine surfactant Y-11699, 0.2g of xanthan gum, 0.3g of chitosan, 1g of isothiazolinone, 1.5g of urea, and 1.5g of sodium ethylenediaminetetraacetate. ② Add 1.5g of urea to 75.5g of deionized water and stir at 300rpm for 10min until completely transparent to obtain pretreated deionized water. ③ Take 45g of pretreated deionized water and add 8g of tetrasiloxane surfactant (2) and 12g of bis-(γ-triethoxysilylpropyl)-amine surfactant Y-11699 sequentially at 1000rpm and stir for 20min to obtain a surfactant complex system. ④ At 1500rpm, add 0.2g of xanthan gum and 1.5g of sodium ethylenediaminetetraacetate sequentially to the surfactant complex system solution and stir for 15min. ⑤ At 1500 rpm, add 0.3 g of chitosan and stir for 15 min; at 1000 rpm, add 1 g of isothiazolinone and replenish the remaining pretreated deionized water, stir for 20 min to obtain the foam extinguishing agent stock solution, as follows. Figure 6 As shown. The main difference between Comparative Example 7 and Example 3 in the preparation process is that in Comparative Example 7, tetrasiloxane surfactant and trisiloxane surfactant were directly mixed to prepare a surfactant complex solution; then, xanthan gum and sodium ethylenediaminetetraacetate were directly added to the surfactant complex solution. Figure 6 At day 0, the stock solution was a uniform milky white liquid with no stratification or sedimentation. After 15 days, the liquid began to separate into layers, with a thinner emulsion on top and white flocculent or granular sediment appearing on the bottom. After 30 days, the stratification intensified further, with a large amount of sediment accumulating at the bottom and flocculent material adhering to the bottle walls. This indicates that the prepared foam fire extinguishing agent sample has poor stability and a short shelf life.

[0171] Based on the foam extinguishing agent stock solution described in Examples 1-4 and Comparative Examples 1-6 above, a 3% foam extinguishing agent solution was obtained by diluting it at a volume ratio of stock solution:water = 3:97. Based on the characteristics of fires involving large oil-filled equipment in converter stations (substations) and existing mainstream foam extinguishing systems, a positive pressure foaming system (referring to standard GB 27897-2011 "Class A Foam Extinguishing Agents") was used to determine the foaming ratio and 25% separation time of the foam extinguishing agent. Simultaneously, considering the combustion characteristics of transformer oil fires, a 4.52m... 2 A transformer oil pool fire source model was used (the oil pool structure and test procedures were based on standard GB 27897-2011 "Class A Foam Extinguishing Agents"). The initial transformer oil temperature was controlled at 150±5℃, and the extinguishing time and fire resistance time were tested using a positive pressure foaming system. Simultaneously, the film-forming performance of the foam extinguishing agent solution on the transformer oil surface was tested. The specific test method was as follows: ① The equipment used included a miniature injection pump, an oil pan (15cm in diameter), and a high-speed camera; ② 50mL of transformer oil was placed in the oil pan, and the needle of the miniature injection pump was positioned 2cm directly above the center of the oil pan; ③ At 25℃, the foam solution was dripped onto the transformer oil surface at a rate of 12μL / drop using the miniature injection pump. The camera recorded the process of the foam droplets spreading on the transformer oil surface, and the rate of change of the spreading area over time was calculated as the film-forming rate. The performance of the foam extinguishing agents corresponding to Examples 1-4 and Comparative Examples 1-6, as well as the 3% commercial aqueous film-forming foam extinguishing agent (AFFF), measured using the above method are shown in the table below. Figure 7-10 As shown:

[0172]

[0173] From the table above and Figure 7-10 It is evident that the high-efficiency and environmentally friendly foam fire extinguishing agent of this invention (Examples 1-4) exhibits a faster film-forming speed and shorter extinguishing time compared to Comparative Examples 1-6; and compared to 3% AFFF, it demonstrates a higher foaming ratio, higher biodegradability, shorter extinguishing time, and longer 25% eluent release time and fire resistance time. Therefore, the high-efficiency and environmentally friendly foam fire extinguishing agent of this invention possesses excellent performance. Experimental results show that the foaming ratio of this fire extinguishing agent is 7-9 times; the 25% eluent release time is 13-15 min; the extinguishing time is 57-95 s; the fire resistance time is 12 min 17 s-14 min 32 s; and the film-forming speed is 1.5-2.3 cm. 2 / s; 28-day biodegradation rate is 97%-99%.

[0174] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A highly efficient and environmentally friendly foam fire extinguishing agent, characterized in that: It consists of the following components by mass percentage: 15%-30% organosilicon surfactant compound system, 0.3%-1% biopolymer polysaccharide composite stabilizer, 0.8%-1.2% preservative, 1%-2% cosolvent, 1%-2% chelating agent, and the balance is water, with the total of all components being 100%. The organosilicon surfactant compound system consists of a tetrasiloxane surfactant and a trisiloxane surfactant in a mass ratio of 5-10:10-20; the tetrasiloxane surfactant is one or both of the structures shown in formulas (1) and (2) below: (1) (2) ； Trisiloxane surfactants are one or more of vinylsilane, epoxysilane, aminosilane, and ureosilane.

2. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The preparation method of the tetrasiloxane surfactant shown in formula (1) includes the following steps: S1. In an organic solvent, tris(trimethylsiloxy)silane is reacted with ethylene oxide in the presence of sodium triphenylmethyl, and after acidification, tris(trimethylsiloxy)silylethyl alcohol is obtained. S2. In an organic solvent, using tris(trimethylsiloxy)silylethyl alcohol as a raw material, the reaction is carried out with Jones' reagent to obtain a carboxylic acid intermediate; S3. In an organic solvent, using amino polyether alcohol Using bromoacetic acid and anhydrous sodium carbonate as raw materials, an amino polyether carboxylic acid is reacted with sodium hydroxide to obtain amine compounds. S4. In an organic solvent, using a carboxylic acid intermediate as a raw material, and using dicyclohexylcarbodiimide DCC as a condensing agent, reacts with an amine compound to obtain the tetrasiloxane surfactant shown in formula (1).

3. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The preparation method of the tetrasiloxane surfactant shown in formula (2) includes the following steps: S1. In an organic solvent, tris(trimethylsiloxy)silane is reacted with ethylene oxide in the presence of sodium triphenylmethyl to obtain a sodium alkoxide intermediate. S2. In an organic solvent, using sodium alkoxide intermediate as raw material, sodium 3-bromopropane sulfonate is used to react and obtain the tetrasiloxane surfactant shown in formula (2).

4. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The vinyl silane is one or more of the following: vinyltriethoxysilane surfactant A-151NT, vinyltri(2-methoxyethoxy)silane surfactant Crosile-172, and vinyltrimethoxysilane surfactant SF-Y171; the epoxy silane is the epoxy silane surfactant SILQUEST. One or more of the following surfactants are selected: A-186, 3-glycidyl etheroxypropylmethyldiethoxysilane surfactant WETLINK78, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane surfactant COATOSIL-11170; the aminosilane is one or more of the following surfactants: bis-(γ-triethoxysilylpropyl)-amine surfactant Y-11699, bis-(3-(triethoxysilyl)-propyl)-amine surfactant A-1170, and 3-aminopropyltriethoxysilane KBE-90; the ureosilane is one or more of the following surfactants: γ-ureapropyltrimethoxysilane surfactant A-1524, γ-ureapropyltrialkoxysilane surfactant A-1160, and ureapropyltrimethoxysilane surfactant XH-1524.

5. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The biopolymer polysaccharide composite stabilizer is composed of thickening biopolymer polysaccharides and interface-stabilizing biopolymer polysaccharides.

6. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 5, characterized in that: The mass ratio of the thickening biopolymer polysaccharide to the interface-stabilizing biopolymer polysaccharide is 0.1-0.5:0.2-0.

5.

7. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 5, characterized in that: The thickening biopolymer polysaccharide is one or more of xanthan gum, guar gum, tamarind gum, and guar gum.

8. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 5, characterized in that: The interface-stabilized biopolymer polysaccharide is one or more of peppermint seed gum, chitosan, gum arabic, and soybean polysaccharides.

9. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The preservative is one or a mixture of two of potassium sorbate and isothiazolinone.

10. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The co-solvent is one or more of urea, formamide, sodium xylenesulfonate, and propylene glycol phenyl ether.

11. The high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 1, characterized in that: The chelating agent is sodium ethylenediaminetetraacetate.

12. A method for preparing a high-efficiency and environmentally friendly foam fire extinguishing agent as described in any one of claims 1-11, characterized in that: The process includes the following steps: uniformly mixing an organosilicon surfactant compound system, a biopolymer polysaccharide composite stabilizer, a preservative, a cosolvent, a chelating agent, and water to obtain the high-efficiency and environmentally friendly foam fire extinguishing agent.

13. The method for preparing the high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 12, characterized in that: Includes the following steps: Pretreated water is obtained by adding a co-solvent to water and stirring until it becomes completely transparent. Two portions of the pretreated water are taken and tetrasiloxane surfactant and trisiloxane surfactant are added to them respectively to prepare tetrasiloxane surfactant solution and trisiloxane surfactant solution. These solutions are then mixed to obtain an organosilicon surfactant compound system solution. A portion of the pretreated water is taken and a thickening biopolymer polysaccharide and a chelating agent are added sequentially to prepare a pre-emulsion. The pre-emulsion is added to the organosilicon surfactant compound system solution, and then an interface-stabilizing biopolymer polysaccharide, a preservative, and the remaining pretreated water are added sequentially and mixed evenly to obtain the high-efficiency and environmentally friendly foam fire extinguishing agent.

14. The method for preparing the high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 12 or 13, characterized in that: Includes the following steps: S1. Water pretreatment: Add a co-solvent to water and stir until completely transparent to obtain pretreated water; S2. Preparation of organosilicon surfactant compound system solution: Take a portion of pretreated water, add tetrasiloxane surfactant, and stir to obtain tetrasiloxane surfactant solution; take a portion of pretreated water, add trisiloxane surfactant, and stir to obtain trisiloxane surfactant solution. A solution of organosilicon surfactant complex was prepared by adding a solution of trisiloxane surfactant to a solution of tetrasiloxane surfactant and stirring. S3. Add biopolymer polysaccharide composite stabilizer: Take a portion of the pretreated water, add thickening biopolymer polysaccharide and chelating agent in sequence, prepare a pre-emulsion under stirring conditions, add to the organosilicon surfactant compound system solution and stir, add interface-stabilizing biopolymer polysaccharide and stir. S4. Add preservative: Add preservative under stirring conditions, and add the remaining pretreated water. After stirring, the high-efficiency and environmentally friendly foam fire extinguishing agent is obtained.

15. The method for preparing the high-efficiency and environmentally friendly foam fire extinguishing agent according to claim 14, characterized in that: In S1, the stirring speed is 300 rpm and the time is 10 min; in S2, the stirring speed is 500-1000 rpm and the time is 10-20 min; in S3, the stirring speed is 1500 rpm and the time is 15-20 min; in S4, the stirring speed is 1000 rpm and the time is 10-25 min.

16. The application of a high-efficiency and environmentally friendly foam fire extinguishing agent as described in any one of claims 1-11 in fire extinguishing of oil-filled equipment in power systems.

17. A fire extinguishing device, characterized in that: It contains the highly efficient and environmentally friendly foam fire extinguishing agent as described in any one of claims 1-11.

Images