Phosphorus-containing ferrocene derivatives and fire extinguishing agents, and preparation method and application thereof

Abstract

The application relates to the technical field of energy storage battery emergency fire safety, and discloses a phosphorus-containing ferrocene derivative and a fire extinguishing agent as well as a preparation method and application thereof. The structural formula of the phosphorus-containing ferrocene derivative is shown as formula I. The fire extinguishing agent contains a flame retardant, a hydrocarbon surfactant, an organic silicon surfactant, a thickening agent and a preservative, wherein the flame retardant is the phosphorus-containing ferrocene derivative. The phosphorus-containing ferrocene derivative has excellent flame retardation, the phosphorus-containing ferrocene derivative is used as the flame retardant for preparing the fire extinguishing agent, the fire extinguishing agent has strong inhibition on lithium ion battery fire, can more efficiently perform fire extinguishing operation, reduces water consumption, simultaneously has the function of rapid cooling, and effectively prevents battery afterflame.

Description

Technical Field

[0001] This invention relates to the field of emergency fire safety technology for energy storage batteries, specifically to a phosphorus-containing ferrocene derivative and a fire extinguishing agent, as well as their preparation method and application. Background Technology

[0002] With the widespread use of lithium-ion batteries in various industries and fields, their safety issues have gradually come to the forefront of public attention. These safety concerns severely limit the development of lithium-ion batteries, making a suitable fire extinguishing agent for lithium-ion battery fires urgently needed.

[0003] The mechanisms of fire extinguishing agents are mainly divided into isolation, asphyxiation, cooling, and chemical inhibition. However, since batteries can provide the three essential elements for combustion themselves, battery fires are often difficult to extinguish. Currently, commonly used fire extinguishing agents for extinguishing battery fires can be divided into gaseous fire extinguishing agents (CO2, heptafluoropropane, C6F120, etc.), liquid fire extinguishing agents (water-based fire extinguishing agents, liquid nitrogen, etc.), and solid fire extinguishing agents (dry powder, aerosol fire extinguishing agents, etc.). Solid fire extinguishing agents are almost ineffective in extinguishing lithium battery fires. Gaseous fire extinguishing agents are favored in precision instrument and electrical fires due to their advantages such as non-conductivity, non-corrosiveness, no residue, and fast flow rate. However, gaseous fire extinguishing agents have limited cooling performance for lithium battery fires, resulting in poor effectiveness in preventing reignition. Water is the preferred extinguishing agent carrier for lithium battery fires, and liquid fire extinguishing agents for battery fires are mostly water-based, including pure water, water with additives, and foam. Water has an extremely high specific heat capacity and excellent cooling performance, but using water to extinguish battery fires consumes a very large amount of water, and water's conductivity makes it destructive to batteries.

[0004] In general, there are currently no fire extinguishing products specifically designed for battery fires. Therefore, developing a lithium-ion battery fire extinguishing agent that is highly efficient in extinguishing fires and requires minimal water consumption is an important problem that needs to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of low extinguishing efficiency, high water consumption, and easy reignition in existing water-based battery fire extinguishing agents, and to provide a phosphorus-containing ferrocene derivative, a fire extinguishing agent, its preparation method, and its application. This phosphorus-containing ferrocene derivative has excellent flame-retardant properties. Using it as a flame retardant in the preparation of fire extinguishing agents has a strong inhibitory effect on lithium-ion battery fires, enabling more efficient fire extinguishing operations, reducing water consumption, and providing rapid cooling to effectively prevent battery reignition.

[0006] To achieve the above objectives, the present invention provides a phosphorus-containing ferrocene derivative, the structure of which is shown in Formula I.

[0007]

[0008] Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently a ferrocene methylene group, sodium, potassium, or hydrogen, and R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 At least one of them is a ferrocene methylene group, and at least one of R1 and R2 is sodium, potassium, or hydrogen; at least one of R3 and R4 is sodium, potassium, or hydrogen; at least one of R5 and R6 is sodium, potassium, or hydrogen; at least one of R7 and R8 is sodium, potassium, or hydrogen; and R9 and R 10 At least one of them is sodium, potassium or hydrogen, R 11 and R 12 At least one of them is sodium, potassium or hydrogen.

[0009] Preferably, the number of ferrocene methylene groups in the phosphorus-containing ferrocene derivative is ≤6.

[0010] Preferably, the structure of the phosphorus-containing ferrocene derivative is as follows:

[0011]

[0012] A second aspect of the present invention provides a method for preparing phosphorus-containing ferrocene derivatives, the method comprising:

[0013] (1) In the presence of a catalyst, hydroxymethyl ferrocene is esterified with phytic acid;

[0014] (2) Optionally, the esterification product is reacted with a base.

[0015] Preferably, in step (1), the molar ratio of hydroxymethyl ferrocene to phytic acid is 1.2-6.5:1.

[0016] Preferably, in step (1), the conditions for the esterification reaction include: a temperature of 70-90°C and a time of 4-6 hours.

[0017] Preferably, in step (1), the catalyst is a combination of dicyandiamide and urea.

[0018] Preferably, the molar ratio of urea to phytic acid is 0.5-1.5:1.

[0019] Preferably, the molar ratio of dicyandiamide to urea is 0.4-1.2:1.

[0020] Preferably, in step (1), the method specifically includes: mixing hydroxymethyl ferrocene, phytic acid, catalyst, solvent and dehydrating agent to carry out an esterification reaction.

[0021] Preferably, the dehydrating agent is selected from one or more of toluene, xylene, and cyclohexane.

[0022] Preferably, the weight ratio of the dehydrating agent to phytic acid is 0.5-1:1.

[0023] Preferably, in step (2), the molar ratio of the esterification product to the base is 1:9-11.

[0024] Preferably, the alkali is selected from sodium hydroxide and / or potassium hydroxide.

[0025] Preferably, in step (2), the reaction conditions include: a temperature of 20-40°C and a time of 0.2-1h.

[0026] A third aspect of the present invention provides the application of the phosphorus-containing ferrocene derivatives described above as flame retardants.

[0027] A fourth aspect of the present invention provides a fire extinguishing agent comprising a flame retardant, a hydrocarbon surfactant, an organosilicon surfactant, a thickener, and a preservative.

[0028] The flame retardant is the phosphorus-containing ferrocene derivative mentioned above.

[0029] Preferably, the extinguishing agent also contains water.

[0030] Preferably, the fire extinguishing agent contains 0.8-2.0% by weight of flame retardant, 1.5-3.5% by weight of hydrocarbon surfactant, 0.8-1.5% by weight of organosilicon surfactant, 0.2-1.0% by weight of thickener, 0.1-0.5% by weight of preservative, and the balance is water.

[0031] Preferably, the hydrocarbon surfactant is selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers, polysorbates, and cocoamide.

[0032] Preferably, the organosilicon surfactant is selected from one or more of polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and hydroxyl polyether-modified polyorganosiloxane.

[0033] Preferably, the thickener is selected from one or more of xanthan gum, hydroxypropyl guar gum, polyvinyl alcohol, and hydroxymethyl cellulose.

[0034] Preferably, the preservative is sodium benzoate.

[0035] The fifth aspect of this invention provides an application of the fire extinguishing agent described above in the extinguishing of lithium-ion battery fires.

[0036] Compared with the prior art, the present invention has the following main advantages:

[0037] (1) The phosphorus-containing ferrocene derivative provided by the present invention has phosphorus-containing flame-retardant groups and ferrocene free radical quenching groups, with a phosphorus content as high as 21.7%, and has excellent flame-retardant properties. Among them, iron atoms combine with water, air, etc. to generate active intermediates such as FeO and Fe2O3. These active intermediates can combine with key free radicals such as O·, O2 and OH· generated during combustion, and block the free radical chain reaction. When the phosphorus-containing ferrocene derivative is used as a flame retardant in the fire extinguishing agent, the phosphorus element in the phosphorus-containing ferrocene derivative forms a carbon layer during the fire extinguishing process, which can reduce the heat conduction from the flame to the combustible material and can extinguish the fire efficiently and quickly.

[0038] In preferred cases, when the phosphorus-containing ferrocene derivative has the structure shown in Formula II or Formula III, it is not necessary to adjust the pH value when preparing foam fire extinguishing agents or fine water mist fire extinguishing agents to prepare fire extinguishing agents that meet the specifications.

[0039] (2) The present invention creatively esterifies hydroxymethyl ferrocene containing transition metals with phytic acid. Using these two specific reaction raw materials, phosphorus-containing ferrocene derivatives with excellent flame retardant properties can be obtained by using a simple method.

[0040] (3) Compared with commonly used dry powder battery fire extinguishing agents, the fire extinguishing agent obtained by combining phosphorus-containing ferrocene derivatives with specific structures with hydrocarbon surfactants, organosilicon surfactants, thickeners, preservatives and water can block the free radical combustion chain reaction, has high fire extinguishing efficiency, can quickly extinguish open flames, and can also quickly cool down and effectively prevent battery reignition; at the same time, due to the short fire extinguishing time and small amount of fire extinguishing agent, the water consumption is greatly reduced and the cooling effect is improved.

[0041] In a preferred embodiment, limiting the content of each component in the fire extinguishing agent of the present invention to a specific range can further improve the fire extinguishing effect and reduce the fire extinguishing time.

[0042] (4) Since the fire extinguishing agent provided by the present invention contains phosphorus-containing ferrocene derivatives with excellent flame retardant properties as flame retardants, the fire extinguishing efficiency of the fire extinguishing agent can be improved when using non-fluorocarbon surfactants, so that the fire extinguishing agent in the present invention does not contain fluorocarbon surfactants and has low toxicity and environmental protection.

[0043] (5) The fire extinguishing agent provided by the present invention has a wide range of applications, especially suitable for lithium-ion battery fire extinguishing agents, and can also be used to extinguish Class A and Class B fires. Attached Figure Description

[0044] Figure 1 The infrared characterization spectrum of ferrocene phytate with the formula IV structure is shown.

[0045] Figure 2 This is the phosphorus NMR spectrum of ferrocene phytate with the formula IV structure.

[0046] Figure 3 This is the primary mass spectrum of ferrocene phytate with the formula IV structure.

[0047] Figure 4 This is a secondary mass spectrum of ferrocene phytate with the structure of formula IV.

[0048] Figure 5 This is the primary mass spectrum of disubstituted ferrocene phytate with the V-structure.

[0049] Figure 6 This is a secondary mass spectrum of disubstituted ferrocene phytate with the V-structure.

[0050] Figure 7 This is the phosphorus NMR spectrum of disubstituted ferrocene phytate with the V-structure. Detailed Implementation

[0051] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0052] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0053] The first aspect of this invention provides a phosphorus-containing ferrocene derivative, the structure of which is shown in Formula I.

[0054]

[0055] Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently a ferrocene methylene group, sodium, potassium, or hydrogen, and R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12At least one of them is a ferrocene methylene group, and at least one of R1 and R2 is sodium, potassium, or hydrogen; at least one of R3 and R4 is sodium, potassium, or hydrogen; at least one of R5 and R6 is sodium, potassium, or hydrogen; at least one of R7 and R8 is sodium, potassium, or hydrogen; and R9 and R 10 At least one of them is sodium, potassium or hydrogen, R 11 and R 12 At least one of the 12 substituents is sodium, potassium, or hydrogen. That is, in the ferrocene-containing phosphorus derivative of this invention, at least one of the 12 substituents is a ferrocene methylene group, and the other substituents can be sodium, potassium, or hydrogen, and the two substituents on the same phosphate group cannot both be ferrocene methylene groups. In this invention, the ferrocene methylene group is...

[0056] The inventors of this invention discovered through research that the iron atoms in the ferrocene methylene group of the compound having the structure shown in Formula I can combine with water, air, etc. to generate active intermediates such as FeO and Fe2O3. These active intermediates can combine with key free radicals such as O·, O2, and OH· generated during combustion, thus blocking the free radical chain reaction. Furthermore, the phosphate group in the compound is a phosphorus-containing flame-retardant group, and the phosphorus content in the compound shown in Formula I is as high as about 21%. Therefore, the phosphorus-containing ferrocene derivative has excellent flame-retardant properties.

[0057] When this phosphorus-containing ferrocene derivative is used as a flame retardant in a fire extinguishing agent, the phosphorus element in the phosphorus-containing ferrocene derivative forms a char layer during the fire extinguishing process, which can reduce the heat transfer from the flame to the combustible material, thereby extinguishing the fire efficiently and quickly.

[0058] In a specific embodiment, the number of ferrocene methylene groups in the phosphorus-containing ferrocene derivative is ≤6.

[0059] In a more specific embodiment, the structure of the phosphorus-containing ferrocene derivative is shown below:

[0060]

[0061]

[0062] When the phosphorus-containing ferrocene derivative has the structure of formula IV and formula V, the pH value is low, and it is directly used as a flame retardant to prepare fire extinguishing agents, which does not meet the specifications of foam fire extinguishing agents. Therefore, the pH value needs to be adjusted during the preparation of fire extinguishing agents. When the phosphorus-containing ferrocene derivative has the structure of formula II and formula III, the pH value does not need to be adjusted when preparing foam fire extinguishing agents or fine water mist fire extinguishing agents, and fire extinguishing agents that meet the specifications can be prepared.

[0063] A second aspect of the present invention provides a method for preparing phosphorus-containing ferrocene derivatives, the method comprising:

[0064] (1) In the presence of a catalyst, hydroxymethyl ferrocene is esterified with phytic acid;

[0065] (2) Optionally, the esterification product is reacted with a base.

[0066] The inventors discovered through research that esterification of hydroxymethyl ferrocene with phytic acid can produce R1, R2, R3, R4, R5, R6, R7, R8, R9, and R... 10 R 11 and R 12 Each of these is an independent phosphorus-containing ferrocene derivative (ferrocene methyl phytate) with a ferrocene methylene group or hydrogen; further reaction with a base yields R1, R2, R3, R4, R5, R6, R7, R8, R9, and R 10 R 11 and R 12 The phosphorus-containing ferrocene derivatives obtained in steps (1) and (2) are each composed of a ferrocene methylene group, sodium, and potassium. Both derivatives exhibit excellent flame retardant properties. The method described in this invention is simple and easy to operate.

[0067] In this invention, to obtain compounds with the structure shown in Formula I, the molar ratio of hydroxymethyl ferrocene to phytic acid needs to be limited to a specific range. In a preferred embodiment, the molar ratio of hydroxymethyl ferrocene to phytic acid can be 1.2-6.5:1, for example 1.2:1, 2.5:1, 3.5:1, 4.5, 5.5:1, or 6.5:1. When the molar ratio of hydroxymethyl ferrocene to phytic acid is small, products with the structures of Formula II and Formula IV are obtained; when the molar ratio of hydroxymethyl ferrocene to phytic acid is large, phytic acid will undergo esterification with multiple hydroxymethyl ferrocene compounds, forming two or more phosphate ester bonds, i.e., the resulting phosphorus-containing ferrocene derivative has two or more ferrocene methylene groups.

[0068] In order to obtain a compound with the structure shown in Formula I, in a preferred embodiment, the esterification reaction conditions include a temperature of 70-90°C and a time of 4-6 hours.

[0069] In this invention, the catalyst can be a specific combination of dicyandiamide and urea, and dicyandiamide and urea need to be added simultaneously to obtain the target product of Formula I. In a specific embodiment, the molar ratio of urea to phytic acid can be 0.5-1.5:1. Specifically, the molar ratio of dicyandiamide to urea can be 0.4-1.2:1.

[0070] In a specific embodiment, the method includes: mixing hydroxymethyl ferrocene, phytic acid, a catalyst, a solvent, and a dehydrating agent to carry out an esterification reaction.

[0071] In a more specific embodiment, the method includes: dissolving hydroxymethyl ferrocene, phytic acid and catalyst in a solvent at room temperature (15-30°C), then adding a dehydrating agent, heating to 70-90°C and reacting for 4-6 hours, then cooling to room temperature (15-30°C), and removing the solvent, dehydrating agent and excess hydroxymethyl ferrocene by multiple water washings and vacuum distillation to obtain a phosphorus-containing ferrocene derivative (i.e., ferrocene methyl phytate).

[0072] In this invention, the dehydrating agent can be a conventional choice in the art. In a specific embodiment, the dehydrating agent can be selected from one or more of toluene, xylene, and cyclohexane, preferably toluene.

[0073] There are no particular restrictions on the amount of the dehydrating agent used; it can be added according to conventional requirements. In a specific embodiment, the weight ratio of the dehydrating agent to phytic acid can be 0.5-1:1.

[0074] In this invention, the solvent can be any conventional choice in the art. In a specific embodiment, the solvent can be selected from one or more of dimethyl sulfoxide, toluene, and cyclohexane, preferably dimethyl sulfoxide.

[0075] In the method described in this invention, the molar ratio of the esterification product to the base can be 1:9-11.

[0076] In a specific embodiment, the alkali is selected from sodium hydroxide and / or potassium hydroxide.

[0077] In a specific embodiment, the conditions for reacting the esterification product with the base include: a temperature of 20-40°C and a time of 0.2-1 h.

[0078] This invention, by selecting appropriate reaction raw materials, can obtain products with excellent flame retardant properties using only a simple preparation method.

[0079] A third aspect of this invention provides the application of the aforementioned phosphorus-containing ferrocene derivative as a flame retardant. This phosphorus-containing ferrocene derivative possesses phosphorus-containing flame-retardant groups and ferrocene free radical quenching groups, with a phosphorus content as high as approximately 21%, exhibiting excellent flame-retardant properties.

[0080] The fourth aspect of the present invention provides a fire extinguishing agent containing a flame retardant, a hydrocarbon surfactant, an organosilicon surfactant, a thickener, and a preservative, wherein the flame retardant is a phosphorus-containing ferrocene derivative as described above.

[0081] In a preferred embodiment, the extinguishing agent further contains water. Preparing the extinguishing agent of the present invention as a water-based extinguishing agent can quickly extinguish open flames, rapidly cool the flames, effectively prevent reignition, and greatly reduce water consumption.

[0082] This invention combines a phosphorus-containing ferrocene derivative with a specific structure with hydrocarbon surfactants, organosilicon surfactants, thickeners, preservatives, and water to obtain a fire extinguishing agent. This agent has high fire extinguishing efficiency, can block the free radical combustion chain reaction, quickly extinguish open flames, and can also rapidly cool down the battery, effectively preventing battery reignition. At the same time, due to the short fire extinguishing time and small amount of fire extinguishing agent, it not only greatly reduces water consumption but also has a highly efficient cooling effect.

[0083] In this invention, since the fire extinguishing agent contains phosphorus-containing ferrocene derivatives with excellent flame retardant properties as flame retardants, the fire extinguishing efficiency of the fire extinguishing agent can be improved without using fluorocarbon surfactants. Thus, the fire extinguishing agent in this invention can have excellent fire extinguishing efficiency without using fluorocarbon surfactants, avoiding the use of environmentally unfriendly fluorocarbon surfactants.

[0084] In this invention, limiting the content of each component in the fire extinguishing agent to a specific range can further improve the fire extinguishing effect. If the content of one or more components in the fire extinguishing agent is too low, the fire extinguishing effect will be significantly worse.

[0085] In a preferred embodiment, the fire extinguishing agent contains 0.8-2.0% by weight of flame retardant, 1.5-3.5% by weight of hydrocarbon surfactant, 0.8-1.5% by weight of organosilicon surfactant, 0.2-1.0% by weight of thickener, 0.1-0.5% by weight of preservative, and the balance is water.

[0086] In this invention, the hydrocarbon surfactant can be a conventional choice in the art. In specific embodiments, the hydrocarbon surfactant can be selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers, polysorbates, and cocoamide.

[0087] In this invention, the organosilicon surfactant can be a conventional choice in the art. In specific embodiments, the organosilicon surfactant can be selected from one or more of polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and hydroxyl polyether-modified polyorganosiloxane.

[0088] In this invention, the thickener can be a conventional choice in the art. In a specific embodiment, the thickener is selected from one or more of xanthan gum, hydroxypropyl guar gum, polyvinyl alcohol, and hydroxymethyl cellulose.

[0089] In this invention, the preservative can be a conventional choice in the art. In a specific embodiment, the preservative is sodium benzoate.

[0090] The fire extinguishing agent provided by this invention can extinguish open flames in a very short time when used to extinguish batteries, and prevents reignition. Embodiments of this invention have verified that when using the fire extinguishing agent described herein to extinguish lithium-ion batteries, open flames can be extinguished within 30 seconds, and reignition will not occur within 24 hours.

[0091] The preparation method of the fire extinguishing agent described in this invention is simple; the fire extinguishing agent can be obtained simply by mixing the various components in the fire extinguishing agent.

[0092] In a specific embodiment, the method includes mixing a flame retardant, a hydrocarbon surfactant, an organosilicon surfactant, a thickener, a preservative, and water.

[0093] By employing a specific mixing sequence during the preparation of the fire extinguishing agent, the fire extinguishing effect of the prepared agent can be improved. In a preferred embodiment, the method specifically includes: first mixing a thickener with water at 40-60°C, and then second mixing the resulting solution with a flame retardant, a hydrocarbon surfactant, an organosilicon surfactant, and a preservative at room temperature (15-30°C). Both the first and second mixing can be carried out under stirring conditions; specifically, the stirring rate for the first mixing can be 150-250 r / min, and the stirring rate for the second mixing can be 50-80 r / min.

[0094] The fifth aspect of this invention provides an application of the aforementioned fire extinguishing agent in extinguishing fires involving lithium-ion batteries. The fire extinguishing agent provided by this invention has a wide range of applications, is particularly suitable for lithium-ion battery fire extinguishing, and can also be used to extinguish Class A and Class B fires.

[0095] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto. In the following embodiments, the raw materials used were purchased from Shanghai Maclean.

[0096] Example 1

[0097] Preparation of phosphorus-containing ferrocene derivatives:

[0098] At 20°C, hydroxymethyl ferrocene, phytic acid, and catalysts (dicyandiamide and urea) were dissolved in dimethyl sulfoxide (solvent). After complete dissolution, cyclohexane (a dehydrating agent) was added, and the mixture was heated to 70°C and reacted for 4 hours before being cooled to room temperature. The solvent, dehydrating agent, and excess hydroxymethyl ferrocene were removed by repeated washing with water and vacuum distillation to obtain ferrocene methyl phytate with structure IV. Then, ferrocene methyl phytate and sodium hydroxide were reacted at 25°C for 0.2 hours to obtain a phosphorus-containing ferrocene derivative with structure II. The molar ratio of hydroxymethyl ferrocene to phytic acid was 1.2:1; the molar ratio of phytic acid to urea was 1:1; the molar ratio of dicyandiamide to urea was 0.5:1; the mass ratio of the dehydrating agent to phytic acid was 0.5:1; and the molar ratio of ferrocene methyl phytate to sodium hydroxide was 1:11.

[0099] Figure 1 The image shows the infrared spectrum of the phosphorus-containing ferrocene derivative obtained in this embodiment. Figure 2 This is the phosphorus NMR spectrum of the phosphorus-containing ferrocene derivative obtained in this embodiment. From... Figure 1 It can be seen that 3415cm -1 The peak for phytic acid is the -OH peak at 2850 cm⁻¹. -1 This is a saturated CH peak, 1699 cm⁻¹ -1 The peak is P=O, at 1080 cm⁻¹. -1 The peak for the newly generated POC is at 1189 cm⁻¹. -1 It is the primary alcohol -OH on hydroxymethylferrocene. Additionally, 481 cm⁻¹ -1 The peak at this point represents the interaction of the cyclopentadiene ring and Fe. This indicates that hydroxymethyl ferrocene underwent an esterification reaction with phytic acid, synthesizing ferrocene phytate methyl ester. From Figure 2 It can be seen that the absorption peak at 3.3 ppm is the phosphate monoester bond in phytic acid, and the shift peak at -0.75 ppm is considered to be related to the newly formed phosphate diester bond, proving that hydroxymethyl ferrocene has successfully esterified with phytic acid. Figure 3 and Figure 4 The primary mass spectrometry showed a signal peak at 857.87, consistent with the molecular mass of the target product; the secondary mass spectrometry (858→793→737→672→659) indicated the gradual removal of the hydroxymethyl ferrocene group from ferrocene phytate. In summary, the phosphorus-containing ferrocene derivative prepared in this embodiment possesses the structure of Formula II.

[0100] Preparation of extinguishing agents:

[0101] The fire extinguishing agent is composed of the following components: 2.0 wt% ferrocene phosphorus derivative, 1.5 wt% alkyl glycoside, 2.0 wt% polysorbate, 0.5 wt% polyether-modified polydimethylsiloxane, 1.0 wt% trisiloxane polyoxyethylene ether, 1.0 wt% xanthan gum, 0.5 wt% sodium benzoate, and the balance being water.

[0102] Xanthan gum was added to water at 50℃ and 200r / min and stirred until completely dissolved. Heating was then stopped, and the solution was allowed to cool to room temperature. Then, ferrocene phosphorus derivatives, alkyl glycosides, polysorbates, polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and sodium benzoate were added in sequence and stirred at 60r / min until homogeneous to obtain the fire extinguishing agent.

[0103] Fire extinguishing experiment:

[0104] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 5kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 115 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.0kg.

[0105] Example 2

[0106] Preparation of phosphorus-containing ferrocene derivatives:

[0107] At 20°C, hydroxymethyl ferrocene, phytic acid, and a catalyst (dicyandiamide and urea) were dissolved in dimethyl sulfoxide (solvent). After complete dissolution, toluene (a dehydrating agent) was added, and the mixture was heated to 90°C and reacted for 6 hours before cooling to room temperature. The solvent, dehydrating agent, and excess hydroxymethyl ferrocene were removed by repeated washing with water and vacuum distillation to obtain disubstituted ferrocene methyl phytate, i.e., the compound with formula V. Then, ferrocene methyl phytate and sodium hydroxide were reacted at 25°C for 0.2 hours to obtain a phosphorus-containing ferrocene derivative with the structure of formula III. The molar ratio of hydroxymethyl ferrocene to phytic acid was 2.5:1; the molar ratio of phytic acid to urea was 1:1.2; the molar ratio of dicyandiamide to urea was 0.5:1; the mass ratio of the dehydrating agent to phytic acid was 1:1; and the molar ratio of ferrocene methyl phytate to sodium hydroxide was 1:10.

[0108] Phytic acid molecules contain six phosphate groups and twelve hydroxyl groups, including four weakly acidic groups, two moderately acidic groups, and six strongly acidic groups. Within the weakly acidic pKa range of 5.7, one hydrogen atom in the phytic acid molecule dissociates; within the pKa range of 6.8–7.6, two hydrogen atom dissociates; and within the pKa range of 10.0–12.0, three hydrogen atom dissociates.

[0109] according to Figure 5 and Figure 6 The primary mass spectrometer showed a signal peak at 1055.89, consistent with the molecular mass of the target product; the secondary mass spectrometer showed a progressive removal of two hydroxymethyl ferrocene groups from 1056 to 658. According to... Figure 7The absorption peaks at 2.08 ppm to 3.40 ppm represent the phosphate monoester bond in the phytic acid group; the absorption peaks at -1.43 ppm to -0.79 ppm represent the phosphate diester bond in the two symmetrical ferrocene methylene groups. The methylferrocene group increases the electronegativity of the O directly bonded to P, causing a low-field shift in the peak position. In summary, the phosphorus-containing ferrocene derivative prepared in this embodiment has the structure of Formula III.

[0110] Preparation of extinguishing agents:

[0111] The extinguishing agent consists of the following components: 0.8 wt% ferrocene phosphorus derivative, 0.5 wt% alkyl glycoside, 1.0 wt% polysorbate, 0.3 wt% polyether-modified polydimethylsiloxane, 0.5 wt% trisiloxane polyoxyethylene ether, 0.2 wt% xanthan gum, 0.1 wt% sodium benzoate, and the balance being water.

[0112] Xanthan gum was added to water at 50℃ and 200r / min and stirred until completely dissolved. Heating was then stopped, and the solution was allowed to cool to room temperature. Then, ferrocene phosphorus derivatives, alkyl glycosides, polysorbates, polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and sodium benzoate were added in sequence and stirred at 60r / min until homogeneous to obtain the fire extinguishing agent.

[0113] Fire extinguishing experiment:

[0114] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 5kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 153 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.3kg.

[0115] Example 3

[0116] Preparation of phosphorus-containing ferrocene derivatives:

[0117] At 20°C, hydroxymethyl ferrocene, phytic acid, and catalysts (dicyandiamide and urea) were dissolved in dimethyl sulfoxide (solvent). After complete dissolution, cyclohexane (a dehydrating agent) was added, and the mixture was heated to 70°C and reacted for 4 hours before being cooled to room temperature. The solvent, dehydrating agent, and excess hydroxymethyl ferrocene were removed by repeated washing with water and vacuum distillation to obtain ferrocene methyl phytate. Then, ferrocene methyl phytate and sodium hydroxide were reacted at 25°C for 0.2 hours to obtain a phosphorus-containing ferrocene derivative. The molar ratio of hydroxymethyl ferrocene to phytic acid was 1.2:1; the molar ratio of phytic acid to urea was 1:1; the molar ratio of dicyandiamide to urea was 0.5:1; the mass ratio of the dehydrating agent to phytic acid was 0.5:1; and the molar ratio of ferrocene methyl phytate to sodium hydroxide was 1:11.

[0118] The structure of the phosphorus-containing ferrocene derivative obtained in this embodiment is Formula II.

[0119] Preparation of extinguishing agents:

[0120] The extinguishing agent consists of the following components: 1.5 wt% ferrocene phosphorus derivative, 1.0 wt% alkyl glycoside, 1.5 wt% polysorbate, 0.4 wt% polyether-modified polydimethylsiloxane, 0.8 wt% trisiloxane polyoxyethylene ether, 0.5 wt% xanthan gum, 0.3 wt% sodium benzoate, and the balance being water.

[0121] Xanthan gum was added to water at 50℃ and 200r / min and stirred until completely dissolved. Heating was then stopped, and the solution was allowed to cool to room temperature. Then, ferrocene phosphorus derivatives, alkyl glycosides, polysorbates, polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and sodium benzoate were added in sequence and stirred at 60r / min until homogeneous to obtain the fire extinguishing agent.

[0122] Fire extinguishing experiment:

[0123] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 5kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 130 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.1kg.

[0124] Example 4

[0125] The preparation method of the phosphorus-containing ferrocene derivative is the same as in Example 1, except that the reaction temperature is 75°C and the reaction time is 5 hours. The obtained phosphorus-containing ferrocene derivative has the structure of Formula II.

[0126] Preparation of extinguishing agents:

[0127] The fire extinguishing agent consists of the following components: 2.0 wt% ferrocene phosphorus derivative, 1.5 wt% fatty alcohol polyoxyethylene ether, 2.0 wt% cocoamide, 0.5 wt% hydroxyl polyether modified polyorganosiloxane, 1.0 wt% trisiloxane polyoxyethylene ether, 0.5 wt% hydroxypropyl guar gum, 0.5 wt% sodium benzoate, and the balance being water.

[0128] Hydroxypropyl guar gum was added to water at 50℃ and 200 rpm and stirred until completely dissolved. Heating was then stopped, and the solution was allowed to cool to room temperature. Then, ferrocene phosphorus derivatives, fatty alcohol polyoxyethylene ether, cocoamide, hydroxyl polyether modified polyorganosiloxane, trisiloxane polyoxyethylene ether, and sodium benzoate were added sequentially and stirred at 60 rpm until homogeneous to obtain a fire extinguishing agent based on ferrocene phosphorus derivatives.

[0129] Fire extinguishing experiment:

[0130] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 10kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 135 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.1kg.

[0131] Example 5

[0132] The preparation method of the phosphorus-containing ferrocene derivative is the same as in Example 1.

[0133] The preparation of the extinguishing agent is the same as in Example 1, except that the phosphorus-containing ferrocene derivative is 0.6% by weight.

[0134] Fire extinguishing experiment:

[0135] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 5kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 225 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.9kg.

[0136] Example 6

[0137] The preparation method of the phosphorus-containing ferrocene derivative is the same as in Example 1.

[0138] The extinguishing agent was prepared in the same manner as in Example 1, except that the alkyl glycoside was 0.6 wt% and the polysorbate was 0.6 wt%.

[0139] Fire extinguishing experiment:

[0140] Eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm) were connected in series, and a heating plate was used to trigger thermal runaway. After the batteries caught fire, 10kg of the extinguishing agent prepared in this embodiment was used to extinguish the fire at a flow rate of 0.5L / min. The flames extinguished within 180 seconds, and spraying continued for another 2 minutes. No reignition occurred within 24 hours. The total amount of extinguishing agent used was 2.5kg.

[0141] Comparative Example 1

[0142] The fire extinguishing agent was prepared according to the method of Example 1, except that 99% diammonium hydrogen phosphate purchased from Shanghai McLean Company was used as a flame retardant instead of the phosphorus-containing ferrocene derivative in Example 1.

[0143] Fire extinguishing experiment:

[0144] The extinguishing agent in this comparative example was used to extinguish eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm in length x width x height) that were in series. The flow rate was 0.5L / min. The open flames were extinguished within 310 seconds. After that, spraying was continued for 2 minutes. The fire reignited within 1 hour. The amount of extinguishing agent used was 3.6kg.

[0145] Comparative Example 2

[0146] A commercially available 3% aqueous film-forming foam extinguishing agent was used to prepare a 20kg foam mixture (purchased from Jiangsu Jiangya Company) to extinguish eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm in length x width x height) that were in series. The flow rate was 11.4L / min. The open flames disappeared within 60 seconds. The spray was continued at 0.5L / min for 2 minutes. Reignition occurred within 30 minutes.

[0147] Comparative Example 3

[0148] The fire was extinguished by using 10 kg of commercially available ABC type dry powder fire extinguishing agent to extinguish 8 commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm in length x width x height) connected in series. The fire was not extinguished.

[0149] Comparative Example 4

[0150] A 4.2MPa piped perfluorohexanone gas fire extinguishing system (purchased from Jinan Noah Company) was used to extinguish the fire on eight commercially available lithium-ion batteries (12V, 200Ah, approximately 320mm x 270mm x 115mm in length x width x height). The fire was extinguished within 20 seconds, and reignition occurred within 10 minutes.

[0151] The results from the examples and comparative examples show that using the ferrocene phosphorus derivatives described in this invention as flame retardants to prepare fire extinguishing agents can not only quickly extinguish open flames after extinguishing lithium-ion battery fires, but also effectively prevent reignition, and the amount of fire extinguishing agent used is small.

[0152] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A phosphorus-containing ferrocene derivative, characterized in that, The structure of this phosphorus-containing ferrocene derivative is shown in Formula I. Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently a ferrocene methylene group, sodium, potassium, or hydrogen, and R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 At least one of them is a ferrocene methylene group, and at least one of R1 and R2 is sodium, potassium, or hydrogen; at least one of R3 and R4 is sodium, potassium, or hydrogen; at least one of R5 and R6 is sodium, potassium, or hydrogen; at least one of R7 and R8 is sodium, potassium, or hydrogen; and R9 and R 10 At least one of them is sodium, potassium or hydrogen, R 11 and R 12 At least one of them is sodium, potassium or hydrogen.

2. The phosphorus-containing ferrocene derivative according to claim 1, characterized in that, The number of ferrocene methylene groups in the phosphorus-containing ferrocene derivative is ≤6.

3. The phosphorus-containing ferrocene derivative according to claim 1 or 2, characterized in that, The structure of the phosphorus-containing ferrocene derivative is shown below:

4. A method for preparing phosphorus-containing ferrocene derivatives, characterized in that, The method includes: (1) In the presence of a catalyst, hydroxymethyl ferrocene is esterified with phytic acid; (2) Optionally, the esterification product is reacted with a base.

5. The method according to claim 4, characterized in that, In step (1), the molar ratio of hydroxymethyl ferrocene to phytic acid is 1.2-6.5:

1.

6. The method according to claim 4 or 5, characterized in that, In step (1), the conditions for the esterification reaction include: a temperature of 70-90°C and a time of 4-6 hours.

7. The method according to any one of claims 4-6, characterized in that, In step (1), the catalyst is a combination of dicyandiamide and urea; Preferably, the molar ratio of urea to phytic acid is 0.5-1.5:1; Preferably, the molar ratio of dicyandiamide to urea is 0.4-1.2:

1.

8. The method according to any one of claims 4-7, characterized in that, In step (1), the method specifically includes: mixing hydroxymethyl ferrocene, phytic acid, catalyst, solvent and dehydrating agent to carry out an esterification reaction.

9. The method according to claim 8, characterized in that, The dehydrating agent is selected from one or more of toluene, xylene, and cyclohexane; Preferably, the weight ratio of the dehydrating agent to phytic acid is 0.5-1:

1.

10. The method according to any one of claims 4-9, characterized in that, In step (2), the molar ratio of the esterification product to the base is 1:9-11; Preferably, the alkali is sodium hydroxide and / or potassium hydroxide; Preferably, in step (2), the reaction conditions include: a temperature of 20-40°C and a time of 0.2-1h.

11. The use of the phosphorus-containing ferrocene derivative according to any one of claims 1-3 as a flame retardant.

12. A fire extinguishing agent, characterized in that, The extinguishing agent contains flame retardants, hydrocarbon surfactants, organosilicon surfactants, thickeners, and preservatives. The flame retardant is a phosphorus-containing ferrocene derivative as described in any one of claims 1-3.

13. The extinguishing agent according to claim 12, characterized in that, The extinguishing agent also contains water; Preferably, the fire extinguishing agent contains 0.8-2.0% by weight of flame retardant, 1.5-3.5% by weight of hydrocarbon surfactant, 0.8-1.5% by weight of organosilicon surfactant, 0.2-1.0% by weight of thickener, 0.1-0.5% by weight of preservative, and the balance is water.

14. The extinguishing agent according to claim 12 or 13, characterized in that, The hydrocarbon surfactant is selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers, polysorbates, and cocoamide; Preferably, the organosilicon surfactant is selected from one or more of polyether-modified polydimethylsiloxane, trisiloxane polyoxyethylene ether, and hydroxyl polyether-modified polyorganosiloxane; Preferably, the thickener is selected from one or more of xanthan gum, hydroxypropyl guar gum, polyvinyl alcohol, and hydroxymethyl cellulose; Preferably, the preservative is sodium benzoate.

15. The application of the extinguishing agent according to any one of claims 12-14 in extinguishing fires in lithium-ion batteries.

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