Bionic intelligent response type gas explosion suppression gel material as well as preparation method and application thereof

Abstract

The invention discloses a bionic intelligent response type gas explosion suppression gel material and a preparation method and application thereof.Chitosan-montmorillonite in the material is subjected to freeze drying to form a dual-scale pore channel structure containing micron-scale honeycomb holes and nano-scale capillary vessels, ODTAC is grafted, the material expands when encountering gas, then coal cracks are blocked, and gas-air mixing is blocked; the phase change energy storage material adopts paraffin to absorb explosion heat; according to the intelligent response release material, ammonium dihydrogen phosphate is packaged by PNIPAM microspheres, and the ammonium dihydrogen phosphate is released when the temperature reaches 65 + / -2 DEG C. During preparation, sol preparation, emulsion mixing, freeze drying, glutaraldehyde crosslinking and surface grafting modification are sequentially carried out. The preparation method is simple and convenient, and the prepared material can effectively reduce the explosion pressure peak value and the temperature peak value, slow down the flame propagation speed, improve the interface bonding strength, improve the gas adsorption capacity and prolong the action time of an explosion suppressant through the synergistic effect of three mechanisms of physical plugging, heat absorption cooling and chemical inhibition of free radicals, and is suitable for gas explosion prevention and control.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mine gas explosion suppression materials, and in particular to a bionic intelligent response type gas explosion suppression gel material and a preparation method and application thereof. Background Art

[0002] Coal mine gas explosions pose a significant threat to coal industry safety. Prevention and control efforts face two major challenges: rapid fluctuations in gas concentration and the instantaneous release of explosive energy. Currently, gas explosion suppression technologies primarily consist of physical blocking and chemical suppression. The former, exemplified by the paraffin phase-change gel described in Chinese Patent CN111116998A, can seal boreholes by triggering temperature-induced expansion. However, it suffers from a passive response, expanding only at a fixed temperature of 52°C and unable to sense changes in gas concentration. Its compressive strength is also poor, with a maximum resistance to gas pressures of 2 MPa. The latter, such as the automatic spraying system described in Chinese Patent CN103114869A, utilizes the blast wave to trigger the release of a foam fire extinguishing agent. However, this system suffers from poor timeliness, as the suppressant rapidly decomposes in high-temperature environments, resulting in an effective duration of less than 24 hours. Furthermore, conventional gas explosion suppression materials commonly suffer from three major technical bottlenecks: a lack of multi-mechanism synergy, weak environmental adaptability, and delayed intelligent response. They struggle to simultaneously achieve the synergistic effects of dynamically sealing fissures, absorbing explosion energy, and inhibiting free radical chain reactions. Water-based gels lack temperature resistance and rapidly fail in explosive temperatures exceeding 120°C, resulting in poor adhesion to the coal. Furthermore, they lack a multi-parameter trigger mechanism coupled with gas concentration and temperature, preventing the premature release of explosion suppressants when gas levels exceed limits or temperatures are abnormal. These issues render existing technologies ineffective and costly for preventing and controlling explosions in high-gas mines. Summary of the Invention

[0003] The purpose of the present invention is to provide a bionic intelligent responsive gas explosion suppression gel material and its preparation method and application, so as to solve the problems of existing gas explosion suppression materials such as passive response, poor pressure resistance, poor timeliness, easy failure at high temperature, and poor adhesion to coal, so as to achieve efficient prevention and control of gas explosions and at the same time improve the comprehensive performance and application value of the material.

[0004] To achieve the above objectives, the present invention provides a method for preparing a bionic intelligent responsive gas explosion suppression gel material, comprising the following steps:

[0005] S1, sol preparation;

[0006] S1-1, dissolving chitosan in acetic acid solution to prepare a chitosan solution with a mass concentration of 2.5%;

[0007] S1-2, weighing a certain amount of montmorillonite and adding it to the chitosan solution prepared in step S1-1, wherein the mass ratio of chitosan to montmorillonite is (8-10):1, and uniformly dispersing the montmorillonite in the chitosan solution by ultrasonication to obtain a dispersion;

[0008] S1-3, adding paraffin emulsion and PNIPAM microspheres to the dispersion obtained in step 1-2, wherein the paraffin emulsion accounts for 10% of the mass of chitosan and the PNIPAM microspheres account for 3-5% of the mass of chitosan, and stirring to fully mix the components to obtain a sol; the PNIPAM microspheres are encapsulated with ammonium dihydrogen phosphate, and the ammonium dihydrogen phosphate accounts for 30-40% of the total mass of the PNIPAM microspheres;

[0009] S2. Freeze-drying: Pour the sol prepared in step S1 into a mold, pre-freeze at -50°C for 12 hours to completely freeze the sol, and then freeze-dry in a vacuum to form a porous skeleton with a dual-scale pore structure;

[0010] S3, cross-linking modification treatment: soaking the porous skeleton freeze-dried material formed in step S2 in glutaraldehyde solution, and performing cross-linking reaction at 50°C for 2 hours;

[0011] S4. Surface grafting treatment: soak the material after the cross-linking modification treatment in step S3 in an ODTAC ethanol solution, react at 60° C. for 4 hours, wash and dry to obtain a bionic intelligent responsive gas explosion suppression gel material.

[0012] Furthermore, the specific steps of step S1-1 are: dissolving chitosan in 1 wt% acetic acid solution, stirring at a stirring speed of 300 r / min, and preparing a chitosan solution with a mass concentration of 2.5%.

[0013] Preferably, in step S1-3, the mass concentration of the paraffin emulsion is 5%, the particle size of the paraffin emulsion is 0.5-1 μm, the particle size of the PNIPAM microspheres is 1-3 μm, and the critical solution temperature is 65±2° C.; and the mixture is stirred at a speed of 400 r / min for 2 h.

[0014] Preferably, in step S2, the mold is made of polytetrafluoroethylene, and the sol is cooled to -50°C at a cooling rate of 5°C / min; the vacuum degree is set to ≤10Pa, and vacuum freeze-drying is performed for 48 hours.

[0015] Preferably, in step S3, the mass fraction of the glutaraldehyde solution is 0.3%. After the cross-linking reaction is completed, the material is taken out from the glutaraldehyde solution and rinsed with deionized water for 3-5 times.

[0016] Preferably, in step S4, the mass concentration of the ODTAC ethanol solution is 2%, and the washing is performed by alternating deionized water and ethanol for 3 times, and the drying temperature is 40°C.

[0017] To achieve the purpose of the invention, the present invention also provides a bionic intelligent responsive gas explosion suppression gel material prepared by the above preparation method.

[0018] To achieve the purpose of the invention, the present invention further provides the application of the above-mentioned bionic intelligent responsive gas explosion suppression gel material in gas explosion suppression. The specific application process is as follows:

[0019] (1) Material injection: A directional drill is used to drill a hole with a diameter of 75 mm and a depth of 10-15 m in the coal mining face, and the gel material is injected into the coal body cracks at a pressure of 0.5-1.0 MPa;

[0020] (2) Curing and molding: The gel material expands to 3-4 times its original volume within 30 minutes in a gas environment with a concentration of ≥1.5%, forming an elastic gel layer with a thickness of 5-10 mm;

[0021] (3) Intelligent response: When the ambient temperature exceeds 65°C, PNIPAM microspheres release ammonium dihydrogen phosphate, and paraffin undergoes phase change to absorb heat to achieve gas explosion suppression.

[0022] Preferably, the viscosity of the injected gel material is 2000-3000 mPa·s, and the shear rate of the gel material at 25°C is 10s -1 .

[0023] Preferably, the release rate of ammonium dihydrogen phosphate is 0.5-1.0 g / min·m 2 , sustained release time ≥72h.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] (1) High-efficiency explosion suppression performance: The gel material prepared by the present invention has a triple explosion suppression mechanism of physical barrier, heat absorption and cooling, and chemical inhibition; when the gas concentration is ≥1.5%, the volume of the gel material expands to 3-4 times of its original volume within 30 minutes, forming an elastic gel layer 5-10 mm thick, effectively sealing the coal body cracks and blocking the gas-air mixing; when the explosion occurs, when the temperature is ≥65°C, the PNIPAM microspheres quickly release ammonium dihydrogen phosphate to capture free radicals (such as ·OH, ·H) in the explosion chain reaction, and at the same time, the paraffin undergoes phase change to absorb a large amount of heat, which reduces the peak explosion temperature by more than 400°C, the explosion energy absorption efficiency is ≥60%, the peak explosion pressure is reduced by 64%, and the flame propagation speed is reduced by 62.5% (compared with the blank group).

[0026] (2) Strong environmental adaptability: The gel material prepared by the present invention has a temperature resistance of ≥200°C and can withstand a gas pressure of 5MPa. The gas adsorption capacity under a gas pressure of 0.5MPa is ≥80cm 3 / g, adsorption equilibrium time ≤ 2h, can quickly adsorb gas and reduce gas concentration.

[0027] (3) Excellent material properties: The compressive strength of the gel material prepared by the present invention is ≥2.5MPa, the elongation at break is ≥150%, and the interfacial bonding strength with the coal body is ≥1.2MPa, ensuring its stable existence in complex underground environments and effectively playing an explosion suppression role.

[0028] (4) Environmentally friendly and economical: The chitosan used in the preparation of this invention is a biomass-based material that is biodegradable, reducing environmental pollution. Compared with traditional explosion suppressants, the material cost is reduced by 40%, and the coal reinforcement cost is reduced by 35%, with good economic and environmental benefits.

[0029] (5) Preparation process optimization: In the freeze-drying process of the present invention, the pre-freezing rate and vacuum degree are precisely controlled to ensure the integrity of the pore structure, the mechanical properties of the material are improved through cross-linking modification, and the bonding effect with the coal body is enhanced through surface grafting. The present invention ensures the stability of material performance through the synergistic effect of each step.

[0030] In summary, the present invention constructs an intelligent response system of gas-triggered expansion-high-temperature release of explosion suppressant-phase change heat absorption through the bionic multi-stage pore structure design and temperature-sensitive phase change system, breaking through the bottleneck of existing technologies and achieving active early warning and efficient suppression of gas explosions. The present invention significantly improves the gas explosion suppression effect through unique material design and innovative preparation process, realizes the multifunctionality and green environmental protection of materials, and is suitable for large-scale application in the field of coal mine gas prevention and control. In practical applications, the material can be deployed in coal mining working faces, return air lanes and other areas where gas is easily accumulated. Its intelligent response characteristics can expand and seal cracks in time when the gas concentration rises, and activate the heat absorption and cooling and explosion suppressant release mechanism when the temperature rises; the material is firmly bonded to the coal body and has good long-term stability, while reducing the cost of material and coal body reinforcement. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a graph showing the change in explosion pressure of the material prepared by the present invention over time;

[0032] Figure 2 This is a graph showing the change in explosion temperature of the material prepared by the present invention over time;

[0033] Figure 3 This is a graph showing the change in flame propagation speed of the material prepared by the present invention over time;

[0034] Figure 4 This is the tensile force-displacement curve of the interface bonding strength test between the material prepared by the present invention and the coal body;

[0035] Figure 5This is a graph showing the change in gas adsorption capacity of the material prepared in the present invention over time at a gas pressure of 0.5 MPa;

[0036] Figure 6 This is the SEM image of the material prepared in the present invention. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] Example 1

[0039] A method for preparing a bionic intelligent responsive gas explosion suppression gel material comprises the following steps:

[0040] S1. Preparation of sol

[0041] S1-1. Preparation of chitosan solution: Place an appropriate amount of 1 wt% acetic acid solution in a clean reaction vessel, slowly add chitosan to the acetic acid solution, and stir at 300 rpm using a magnetic stirrer to fully dissolve the chitosan, to prepare a chitosan solution with a mass concentration of 2.5%;

[0042] S1-2. Addition and dispersion of montmorillonite: Weigh a certain amount of montmorillonite at a chitosan to montmorillonite mass ratio of 8:1 and slowly add it to the chitosan solution prepared in step S1-1; after the addition is complete, place the reaction vessel in an ultrasonic device at a frequency of 40 kHz and perform ultrasonic dispersion for 30 minutes to ensure that the montmorillonite is evenly dispersed in the chitosan solution to obtain a dispersion;

[0043] S1-3. Addition of other ingredients: Add paraffin emulsion (mass concentration is 5%) accounting for 10% of the mass of chitosan and poly N-isopropylacrylamide (PNIPAM) microspheres accounting for 3% of the mass of chitosan to the dispersion obtained in step 1-2, the particle size of the paraffin emulsion is 0.5-1 μm, and the paraffin is used as a phase change energy storage material with a melting point of 52±2°C and a latent heat value of ≥180 kJ / kg; the PNIPAM microspheres are encapsulated with ammonium dihydrogen phosphate, and the ammonium dihydrogen phosphate accounts for 30-40% of the total mass of the PNIPAM microspheres; the PNIPAM microspheres are used as a photothermal response material, with a particle size of 1-3 μm and a critical solution temperature of 65±2°C; continue to turn on the magnetic stirrer and stir at a speed of 400 r / min for 2 h to fully mix the ingredients to obtain a sol;

[0044] S2. Freeze-drying to form a porous skeleton

[0045] S2-1. Mold preparation: Select a mold made of polytetrafluoroethylene, clean and dry the mold to ensure that the inside of the mold is clean and free of impurities;

[0046] S2-2, pre-freezing treatment: slowly pour the sol prepared in step S1 into a mold, then place the mold in a low-temperature freezing device, cool the sol to -50°C at a cooling rate of 5°C / min, and maintain this temperature for 12 hours to completely freeze the sol;

[0047] S2-3, vacuum freeze drying: The sample pre-frozen in step S2-2 is placed in a vacuum freeze dryer, the vacuum degree is set to ≤10Pa, and vacuum freeze drying is performed for 48 hours. During the drying process, ice directly sublimates into water vapor and is extracted, thereby forming a porous skeleton with a dual-scale pore structure (such as Figure 6 ); The dual-scale pore structure comprises micron-scale honeycomb pores with a pore size of 20-50 μm and a porosity of 45-60% and nanoscale capillaries with a pore size of 5-10 nm, the nanoscale capillaries being formed by nano-gaps between montmorillonite sheets.

[0048] S3, cross-linking modification treatment

[0049] S3-1. Preparation of crosslinking solution: Accurately weigh an appropriate amount of glutaraldehyde and add it to deionized water to prepare a 0.3% glutaraldehyde solution;

[0050] S3-2, cross-linking reaction: The porous framework formed in step S2 is immersed in the glutaraldehyde solution prepared in step S3-1. The reaction vessel is placed in a thermostatic water bath at 50°C for 2 hours. After the cross-linking reaction is completed, the material is removed from the glutaraldehyde solution and rinsed with deionized water 3-5 times to remove any residual glutaraldehyde on the surface.

[0051] S4. Surface grafting treatment

[0052] S4-1. Preparation of grafting solution: Weigh an appropriate amount of octadecyltrimethylammonium chloride (ODTAC) and add it to ethanol to prepare a 2% ODTAC ethanol solution;

[0053] S4-2, grafting reaction: The cross-linked material was immersed in an ODTAC ethanol solution, and the reaction vessel was placed in a constant temperature water bath, the temperature was controlled at 60° C., and the reaction was carried out for 4 hours. The grafting rate in this step was 1.2-2.0 mmol / g.

[0054] The method for calculating the grafting rate is as follows: First, accurately weigh a certain mass (denoted as m1) of the cross-linked ungrafted material, and complete the grafting operation according to the above-mentioned grafting reaction steps. After the reaction is completed, the material is taken out of the solution and washed alternately with deionized water and ethanol three times to remove the unreacted ODTAC on the surface. Finally, the material is placed in an oven at 40°C and dried to constant weight, and the mass of the grafted material at this time is weighed (denoted as m2). Then, the content of octadecyltrimethylammonium chloride (ODTAC) in the grafted material is determined by elemental analysis (denoted as n, in mmol). The calculation formula of the grafting rate (G) is: G = n / m1 (unit: mmol / g). Through multiple experimental measurements and calculations, the grafting rate is stable in the range of 1.2-2.0mmol / g. After completing the above operations, a bionic intelligent responsive gas explosion suppression gel material is obtained.

[0055] The gel material prepared in this embodiment is applied to gas explosion suppression, and the specific application process is as follows:

[0056] (1) Material injection: A directional drill is used to drill a hole with a diameter of 75 mm and a depth of 10-15 m in the coal mining face, and the gel material as claimed in claim 8 is injected into the coal body cracks at a pressure of 0.5-1.0 MPa; the viscosity of the gel material is 2000-3000 mPa·s (25°C, shear rate 10s -1 );

[0057] (2) Curing and molding: The gel material expands to 3-4 times its original volume within 30 minutes in a gas environment with a concentration of ≥1.5%, forming an elastic gel layer with a thickness of 5-10 mm;

[0058] (3) Intelligent response: When the ambient temperature exceeds 65°C, PNIPAM microspheres release ammonium dihydrogen phosphate at a rate of 0.5-1.0 g / min·m 2 , the continuous release time is ≥72h, and at the same time, the paraffin undergoes phase change and absorbs heat to achieve gas explosion suppression.

[0059] Effect monitoring: Pre-buried distributed optical fiber sensors monitor material expansion rate (error ≤ 5%), temperature change (accuracy ± 0.5°C) and gas concentration (resolution 0.1%) in real time.

[0060] The bionic intelligent responsive gas explosion suppression gel material prepared in this embodiment was tested in terms of controlling explosion pressure, controlling explosion temperature, controlling flame propagation speed, interfacial bonding strength with coal, and gas adsorption performance under a gas pressure of 0.5 MPa. The results are as follows:

[0061] Performance results in controlling explosion pressure are as follows Figure 1As shown in the figure, when the inventive material is not used, the peak explosion pressure reaches 0.95 MPa; after using the inventive material, the peak explosion pressure is significantly reduced to 0.34 MPa. This shows that the material of the present invention can effectively suppress the rise in explosion pressure. Compared with the case where the material is not used, the peak explosion pressure is reduced by about 64.2%. This significant pressure suppression effect can greatly reduce the impact and damage of gas explosions on the surrounding environment and equipment, which is of great significance in coal mine safety production and can effectively reduce the losses caused by explosion accidents.

[0062] The performance results in controlling the explosion temperature are as follows Figure 2 As shown in the figure, without the inventive material, the explosion temperature rapidly rose to 1200°C; however, with the inventive material, the peak explosion temperature only reached 800°C. This demonstrates that the inventive material significantly suppresses explosion temperature, reducing the peak explosion temperature by approximately 400°C compared to the case without the material. By reducing the explosion temperature, high-temperature damage to the coal body and tunnels can be reduced, lowering the risk of secondary disasters caused by high temperatures and ensuring the safety of underground workers.

[0063] The performance results in controlling the flame propagation speed are as follows Figure 3 As shown in the figure, without the inventive material, the peak flame propagation speed reached 40 m / s; after using the inventive material, the peak flame propagation speed dropped to 15 m / s. This demonstrates that the inventive material effectively slows the flame propagation speed, reducing the peak flame propagation speed by approximately 62.5% compared to the case without the material. Slowing the flame propagation speed can prevent the explosion flame from spreading to a wider area, buying valuable time for evacuation and disaster control.

[0064] The performance of the interface bonding strength between the material and the coal body is Figure 4 As shown in the figure, the bond strength between the material and the coal interface reaches 1.2 MPa, reaching the failure point when the tensile force reaches 144.0 kN and the displacement reaches 2.5 mm. This shows that the material of the present invention has a high bond strength with the coal, can firmly adhere to the coal surface, and is not easy to fall off. This ensures the stability and durability of the material's effect in the coal, effectively sealing coal cracks and suppressing gas outbursts.

[0065] The gas adsorption performance at 0.5MPa gas pressure is as follows Figure 5 As shown in the figure, the gas adsorption capacity of the material of the present invention reaches adsorption equilibrium in 1.41h, and the adsorption capacity exceeds 80cm 3 This indicates that the material of the present invention has good gas adsorption performance, can achieve a high adsorption capacity in a relatively short time, can effectively reduce gas concentration, and reduce the risk of gas explosion. At the same time, it meets the requirements for adsorption capacity and adsorption equilibrium time under specific gas pressure, providing strong support for coal mine gas control.

[0066] Example 2

[0067] A method for preparing a bionic intelligent responsive gas explosion suppression gel material comprises the following steps:

[0068] S1. Preparation of sol

[0069] S1-1, preparation of chitosan solution: This step is consistent with Example 1;

[0070] S1-2. Addition and Dispersion of Montmorillonite: Weigh a certain amount of montmorillonite in a chitosan to montmorillonite mass ratio of 10:1 and slowly add it to the chitosan solution. After addition, place the reaction vessel in an ultrasonic device at 40 kHz and perform ultrasonic dispersion for 30 minutes to ensure that the montmorillonite is evenly dispersed in the chitosan solution.

[0071] S1-3. Adding other ingredients: Add 10% paraffin wax emulsion (5% by mass) and 5% PNIPAM microspheres to the dispersed solution. Continue stirring at 400 rpm with a magnetic stirrer for 2 hours to thoroughly mix the ingredients and obtain a sol.

[0072] S2, freeze-drying to form a porous skeleton, this step is consistent with Example 1;

[0073] S3, cross-linking modification treatment, this step is consistent with Example 1;

[0074] S4, surface grafting treatment, this step is consistent with Example 1.

[0075] The gel material prepared in this example is applied to gas explosion suppression, and the specific application process is consistent with that in Example 1.

[0076] The bionic intelligent responsive gas explosion suppression gel material prepared in this embodiment was tested in terms of controlling explosion pressure, controlling explosion temperature, controlling flame propagation speed, interfacial bonding strength with the coal body, and gas adsorption performance under a gas pressure of 0.5 MPa. The testing process was consistent with that in Example 1, and the experimental results were similar to those in Example 1. It exhibited excellent performance in suppressing explosion pressure, controlling explosion temperature, slowing flame propagation speed, enhancing interfacial bonding with the coal body, and gas adsorption, and has application value in the field of coal mine gas explosion prevention and control, effectively ensuring safe coal mine production. Furthermore, the preparation method of the present invention is simple and easy to implement, has low cost, and has good application prospects.

Claims

1. A method for preparing a bionic intelligent responsive gas explosion suppression gel material, characterized in that: The following steps are involved: S1, sol preparation; S1-1, dissolving chitosan in acetic acid solution to prepare a chitosan solution with a mass concentration of 2.5%; S1-2, weighing a certain amount of montmorillonite and adding it to the chitosan solution prepared in step S1-1, wherein the mass ratio of chitosan to montmorillonite is (8-10):1, and uniformly dispersing the montmorillonite in the chitosan solution by ultrasonication to obtain a dispersion; S1-3, adding paraffin emulsion and PNIPAM microspheres to the dispersion obtained in step 1-2, wherein the paraffin emulsion accounts for 10% of the mass of chitosan and the PNIPAM microspheres account for 3-5% of the mass of chitosan, and stirring to fully mix the components to obtain a sol; the PNIPAM microspheres are encapsulated with ammonium dihydrogen phosphate, and the ammonium dihydrogen phosphate accounts for 30-40% of the total mass of the PNIPAM microspheres; S2. Freeze-drying: Pour the sol prepared in step S1 into a mold, pre-freeze at -50°C for 12 hours to completely freeze the sol, and then freeze-dry in a vacuum to form a porous skeleton with a dual-scale pore structure; S3, cross-linking modification treatment: soaking the porous skeleton freeze-dried material formed in step S2 in glutaraldehyde solution, and performing cross-linking reaction at 50°C for 2 hours; S4. Surface grafting treatment: soak the material after the cross-linking modification treatment in step S3 in an ODTAC ethanol solution, react at 60° C. for 4 hours, wash and dry to obtain a bionic intelligent responsive gas explosion suppression gel material.

2. The method for preparing a bionic intelligent responsive gas explosion suppression gel material according to claim 1, characterized in that: The specific steps of step S1-1 are: dissolving chitosan in 1 wt% acetic acid solution, stirring at a stirring speed of 300 r / min, and preparing a chitosan solution with a mass concentration of 2.5%.

3. The method for preparing a bionic intelligent responsive gas explosion suppression gel material according to claim 1, characterized in that: In step S1-3, the mass concentration of the paraffin emulsion is 5%, the particle size of the paraffin emulsion is 0.5-1 μm, the particle size of the PNIPAM microspheres is 1-3 μm, and the critical solution temperature is 65±2° C.; and the mixture is stirred at a speed of 400 r / min for 2 h.

4. The method for preparing a bionic intelligent responsive gas explosion suppression gel material according to claim 1, characterized in that: In step S2, the mold is made of polytetrafluoroethylene, and the sol is cooled to -50°C at a cooling rate of 5°C / min; the vacuum degree is set to ≤10Pa, and vacuum freeze-drying is performed for 48 hours.

5. The method for preparing a bionic intelligent responsive gas explosion suppression gel material according to claim 1, characterized in that: In step S3, the mass fraction of the glutaraldehyde solution is 0.3%. After the cross-linking reaction is completed, the material is taken out from the glutaraldehyde solution and rinsed with deionized water for 3-5 times.

6. The method for preparing a bionic intelligent responsive gas explosion suppression gel material according to claim 1, characterized in that: In step S4, the mass concentration of the ODTAC ethanol solution is 2%, and the washing is performed three times with alternating deionized water and ethanol, and the drying temperature is 40°C.

7. A bionic intelligent responsive gas explosion suppression gel material prepared by the preparation method according to any one of claims 1 to 6.

8. An application of the bionic intelligent responsive gas explosion suppression gel material according to claim 7 in gas explosion suppression, wherein the specific application process is as follows: (1) Material injection: a directional drill is used to drill a hole with a diameter of 75 mm and a depth of 10-15 m in the coal mining face, and the gel material as claimed in claim 7 is injected into the coal body cracks at a pressure of 0.5-1.0 MPa; (2) Curing and molding: The gel material expands to 3-4 times its original volume within 30 minutes in a gas environment with a concentration of ≥1.5%, forming an elastic gel layer with a thickness of 5-10 mm; (3) Intelligent response: When the ambient temperature exceeds 65°C, PNIPAM microspheres release ammonium dihydrogen phosphate, and paraffin undergoes phase change to absorb heat to achieve gas explosion suppression.

9. The use according to claim 8, characterized in that In step (1), the viscosity of the injected gel material is 2000-3000 mPa·s, and the shear rate of the gel material at 25°C is 10s -1 .

10. The use according to claim 8, characterized in that In step (3), the release rate of ammonium dihydrogen phosphate is 0.5-1.0 g / min·m 2 , sustained release time ≥72h.

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