Efficient quick-setting hole sealing material and preparation method thereof

Abstract

The invention discloses an efficient quick-setting hole sealing material and a preparation method thereof, and relates to the technical field of polymer modified materials. The hole sealing material is composed of a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid water reducer, magnesium hydroxide and a cellulose ether thickener. By optimizing the proportion of the components, the material shows excellent leakproofness and construction efficiency in mine gas extraction. Due to the rapid setting characteristic, effective sealing can be formed in a short time, and the sealing agent is suitable for emergency construction scenes. In addition, due to the introduction of the polymer modifier, the mechanical strength and durability of the material are remarkably improved, the permeability coefficient is reduced, and the safety is improved. The preparation method is simple and convenient, and only the components need to be mixed, added with a proper amount of water and uniformly stirred. The novel hole sealing material not only solves the problem that a traditional material is easy to crack in a high-temperature environment, but also has advantages in the aspect of economy, and is suitable for large-scale popularization and application.

Description

Technical Field

[0001] The invention relates to the technical field of polymer modified materials, in particular to a high-efficiency quick-setting pore-sealing material and a preparation method thereof. Background Art

[0002] Mine gas is one of the main disasters in coal mine production. Its outburst and leakage not only threaten the lives of miners, but also seriously affect the normal production of coal mines. Gas outburst is the result of the interaction between coal seam gas pressure, coal body stress and coal body strength. It is sudden, destructive and unpredictable. In order to effectively prevent and control gas outburst, early gas extraction is currently the most commonly used and effective means of control. However, in the process of gas extraction, the sealing quality directly affects the extraction effect, and the key to sealing technology lies in the performance of the sealing material. Therefore, the development of efficient and reliable sealing materials is of great significance to improve gas extraction efficiency and reduce safety hazards.

[0003] At present, conventional sealing methods mainly include mechanical sealing, casing sealing, clay sealing, cement mortar sealing, and polyurethane sealing. Although these methods have met the needs of mine gas extraction to a certain extent, there are still many problems: the mechanical sealing method relies on mechanical devices to seal the borehole, but its sealing effect is greatly affected by the integrity of the borehole wall and the installation accuracy of the mechanical device. Under complex geological conditions, it is difficult for mechanical sealing to completely seal the cracks, which is prone to gas leakage. Casing sealing achieves a sealing effect by inserting a casing into the borehole and filling it with sealing materials. However, this method is complex to construct, has high cost, and is prone to failure under deep high-pressure environments. Clay has been widely used in mine sealing due to its good plasticity and low permeability. However, clay materials are prone to cracking and shrinking in high temperature and dry environments, resulting in sealing failure. In addition, its construction efficiency is low and it is not suitable for large-scale application. As a traditional sealing material, cement mortar has the advantages of low cost and convenient construction. However, ordinary cement mortar has inherent shrinkage problems, and cracks are easily generated during the setting process, resulting in air leakage. In addition, its setting time is long, which is not suitable for scenarios that require rapid construction. Polyurethane foam materials are widely used in mine grouting due to their good expansion and airtightness. However, this type of material cannot completely fill the original cracks around the borehole during the expansion process, and the expansion force is not enough to squeeze and fill the cracks. In addition, polymer foam materials have low strength and high compressibility, lack support for boreholes, and are expensive. Large-scale use will significantly increase production costs.

[0004] In view of the problems existing in the above-mentioned traditional methods and materials, there is an urgent need for a new type of sealing material with excellent performance to meet the requirements of mine gas extraction for efficiency, safety and economy. The ideal high-efficiency quick-setting sealing material should have the following characteristics: Rapid setting: It can complete setting in a short time to improve construction efficiency, especially in emergency situations, it can quickly form a sealing effect. High strength and stability: It has sufficient compressive strength and long-term stability to support the borehole and maintain its structural integrity. Good sealing performance: It can completely fill the borehole and the cracks around it to prevent air leakage. High temperature resistance and non-flammability: It maintains stable performance in high temperature environment and has non-flammable properties to ensure mine safety. Economical: The material cost is moderate, which is convenient for large-scale promotion and application.

[0005] In recent years, in order to overcome the shortcomings of traditional materials, some studies have begun to explore polymer-modified cement-based grouting materials. This type of material improves the performance of the cement matrix by introducing polymer modifiers, so that it has both the strength advantages of cement and the flexibility of polymers. For example: by adding polyacrylate emulsion to the cement matrix, the microstructure of the stone body can be significantly improved, and the compressive strength and toughness can be improved. This material can not only coagulate quickly, but also has good impermeability, and is a potential choice for repairing broken rock masses. By introducing inorganic ceramic components, this material can form a ceramic structure under high temperature conditions, thereby improving fire resistance and long-term stability. By combining inorganic gelling materials with organic polymers, the strength, toughness and sealing properties of the grouting material can be improved at the same time. For example, compounding polyurethane with a cement matrix can not only increase the expansion force, but also enhance the ability to fill cracks.

[0006] Although the new modified grouting materials have improved the performance of traditional materials to a certain extent, there are still some problems that need to be solved: some modified grouting materials require special processes or equipment to prepare, which increases production costs. Some modifiers perform poorly in extreme environments (such as high humidity, high temperature or low temperature), which limits their application scope. Some new materials are expensive and face economic pressure in large-scale promotion. Summary of the invention

[0007] The present invention aims to provide a high-efficiency quick-setting sealing material and a preparation method thereof, which is mainly used in the sealing technology in mine gas extraction. The invention aims to solve the problems of traditional sealing materials in terms of airtightness, construction efficiency and economy, and provide an alternative solution with excellent performance.

[0008] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a high-efficiency quick-setting sealing material, comprising the following components, measured by weight: cement matrix: 40-60 parts, polymer modifier: 5-15 parts, aluminum sulfate: 3-8 parts, quartz sand: 10-20 parts, polycarboxylic acid water reducer: 0.5-2 parts, magnesium hydroxide: 1-3 parts, cellulose ether thickener: 0.1-0.5 parts.

[0009] Preferably, the composition includes the following components by weight: cement matrix: 45-55 parts, polymer modifier: 8-12 parts,

[0010] Aluminum sulfate: 3-8 parts, quartz sand: 12-20 parts, polycarboxylic acid water reducer: 0.5-2 parts, magnesium hydroxide: 1-3 parts, cellulose ether thickener: 0.1-0.5 parts.

[0011] Preferably, the composition comprises the following components in parts by weight: 50 parts of cement matrix, 10 parts of polymer modifier, 5 parts of aluminum sulfate, 16 parts of quartz sand, 1.5 parts of polycarboxylic acid water reducer, 2 parts of magnesium hydroxide and 0.3 parts of cellulose ether thickener.

[0012] Preferably, the cement matrix is ​​cement powder, the grade of which is 52.5, and the specific surface area of ​​the cement matrix is ​​300m 2 / kg; the particle size of aluminum sulfate is 100-200mm; the mesh size of quartz sand is 80-120 mesh; and the particle size of magnesium hydroxide is 50-150mm.

[0013] Preferably, the preparation method of the polymer modifier is as follows: 2 g of ferric chloride is added to 10.0 mL of dopamine hydrochloride solution, ultrasonically treated at 60 W for 5 min, and then stirred with a magnetic stirrer at room temperature for 24 h; thereafter, the resulting mixture is centrifuged at a speed of 12000 rpm for 10 min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24 h to obtain a black powder, then, 10 g of methyl trifluoroethyl carbonate and 30 mL of deionized water are added, and the mixture is continuously shaken at 160° C. for 12 h, and the precipitate is washed twice with PBS buffer, dried at 60° C., and weighed to obtain the obtained product.

[0014] Preferably, the mass concentration of the dopamine hydrochloride solution is 3 mg / mL, and the CAS number of dopamine hydrochloride is 62-31-7.

[0015] Preferably, the polycarboxylate water reducer is one of polyester polycarboxylate water reducer, polyether polycarboxylate water reducer and amphoteric polycarboxylate water reducer; Type: polyester polycarboxylate water reducer Rheobuild 1000, manufacturer: Sika AG; Type: polyether polycarboxylate water reducer Master Glenium SKY, manufacturer: BASF Construction Chemicals; Type: amphoteric polycarboxylate water reducer Superplasticizer K, manufacturer: Fritz-Pak. The addition of polycarboxylate water reducer is only to improve the effect and is not an essential component.

[0016] The cellulose ether thickener is one of carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and ethyl hydroxyethyl cellulose. The cellulose ether thickener has a length of 50 um and a diameter of 70 um.

[0017] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0018] Beneficial Effects

[0019] The polymer modifier plays a key role in the whole high-efficiency rapid-setting pore sealing material, as follows: In this step, 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution. Ferric chloride is a trivalent iron ion, and its strong oxidizing property can react with dopamine hydrochloride to induce the polymerization of dopamine, thereby forming dopamine polymers. This polymer is generated by oxidative polymerization. The oxidizing property of trivalent iron ions promotes the formation of covalent bonds between dopamine molecules in the form of quinoneamine, resulting in the production of polydopamine (PDA). This polymerization process is self-catalytic and can form functionalized coatings on the surfaces of different types of substrates. Apply 60W ultrasonic treatment for 5min, which provides strong shear force by generating high-frequency mechanical vibration, which can promote the mixing and reaction rate of the solution. Ultrasonic treatment can produce a transient high-temperature and high-pressure microenvironment, enhance the interaction efficiency between reactants, and promote the oxidative polymerization reaction of dopamine. In addition, it can effectively remove bubbles in the solution and improve the uniformity of the reaction. A magnetic stirrer was used to stir at room temperature for 24 hours. During this process, continuous stirring ensured that the solution reached a uniform reaction state and avoided inadequate local reaction. At the same time, this continuous stirring can maintain the temperature of the system and the effective collision of the reactants, thereby improving the overall efficiency of the reaction. Long-term stirring also helps to fully diffuse the generated dopamine polymer and promote the subsequent solid-liquid separation effect. After the mixture was centrifuged at 12000rpm for 10min, it was washed twice with deionized water. The purpose of high-speed centrifugation is to separate the generated precipitate from the solution through rapid rotation. Centrifugal force can cause the heavier polymer to settle to the bottom, while the light liquid floats on the upper layer, which facilitates separation. Deionized water washing helps to remove incompletely reacted substances and other dissolved impurities, thereby improving the purity of the final product. A black powder was obtained by a freeze dryer. Freeze drying is usually used for compounds with high stability, especially when residual moisture in the environment is removed. The freeze-drying process directly sublimates water molecules in solid substances into gas by reducing temperature and pressure, thereby protecting the structural integrity of the chemical product and improving its storage stability and redispersibility. This solvent-free process also avoids potential interference with polymer properties. Add 10g of methyl trifluoroethyl carbonate and heat to 160℃ and shake continuously for 12h. Methyl trifluoroethyl carbonate can be used as a fluorinated additive to improve the chemical corrosion resistance of polymers. At this temperature, methyl trifluoroethyl carbonate can react with black powder to form covalent bonds, giving the polymer higher chemical stability and functional properties. Its additional functions also include improving the film-forming properties of the polymer and durability after use. Finally, wash twice with PBS buffer to neutralize and dry at 60℃. The purpose of this step is to further remove excess reagents and by-products and enhance the purity and stability of the product. PBS buffer can maintain a moderate pH value to avoid excessive hydrolysis of polymers containing ester bonds and other sensitive groups.After this treatment, the remaining moisture can be discharged by drying at 60°C to obtain the finished product.

[0020] From a mechanistic point of view, polymer modifiers may work in the following ways: Enhancement of microstructure: The polymer forms a strong bond with the cement matrix, improving the consistency and stability of the internal structure of the material. Filling and sealing: The polymer particles fill between the cement particles, reducing the porosity and improving the sealing performance of the material. Chemical reaction promotion: Some polymers may participate in the cement hydration reaction, accelerating the reaction process and shortening the setting time.

[0021] In summary, polymer modifiers provide significant advantages for high-efficiency fast-setting pore-sealing materials by improving mechanical properties, enhancing sealing effects, and shortening setting time. These characteristics make them promising in engineering applications that require fast response and high performance. By optimizing the type and amount of polymer, the material properties can be further improved to meet specific needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a scanning electron microscope image of the sample prepared in Example 5 of the present invention. DETAILED DESCRIPTION

[0023] The reagents involved in the present invention are all analytically pure. In actual operation, parts by weight are equivalent to kilograms.

[0024] The polycarboxylic acid water reducer is one of polyester polycarboxylic acid water reducer, polyether polycarboxylic acid water reducer and amphoteric polycarboxylic acid water reducer; Type: polyester polycarboxylic acid water reducer Rheobuild 1000, manufacturer: Sika AG; Type: polyether polycarboxylic acid water reducer Master Glenium SKY, manufacturer: BASF Construction Chemicals; Type: amphoteric polycarboxylic acid water reducer Superplasticizer K, manufacturer: Fritz-Pak. The cellulose ether thickener is one of carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and ethyl hydroxyethyl cellulose. The length of the cellulose ether thickener is 50um and the diameter is 70um.

[0025] Example 1

[0026] The high-efficiency quick-setting sealing material comprises the following components, measured in parts by weight: cement matrix: 40 parts, polymer modifier: 15 parts, aluminum sulfate: 3 parts, quartz sand: 20 parts, polycarboxylic acid water reducer: 0.5 parts, magnesium hydroxide: 3 parts, and cellulose ether thickener: 0.1 parts.

[0027] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 100mm; the mesh size of quartz sand is 120 mesh; and the particle size of magnesium hydroxide is 50mm.

[0028] The preparation method of the polymer modifier is as follows: 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution, ultrasonically treated at 60W for 5min, and then stirred with a magnetic stirrer at room temperature for 24h; then, the resulting mixture is centrifuged at a speed of 12000rpm for 10min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24h to obtain a black powder, then, 10g of methyl trifluoroethyl carbonate and 30mL of deionized water are added, and the mixture is continuously shaken at 160°C for 12h, and the precipitate is washed twice with PBS buffer, and weighed after drying at 60°C. The mass concentration of the dopamine hydrochloride solution is 3mg / mL. The polycarboxylic acid water reducer is a polyester polycarboxylic acid water reducer; and the cellulose ether thickener is carboxymethyl cellulose.

[0029] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0030] Example 2

[0031] The high-efficiency quick-setting pore sealing material comprises the following components, measured in parts by weight: cement matrix: 60 parts, polymer modifier: 5 parts, aluminum sulfate: 8 parts, quartz sand: 10 parts, polycarboxylic acid water reducer: 2 parts, magnesium hydroxide: 1 part, and cellulose ether thickener: 0.5 parts.

[0032] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 200mm; the mesh size of quartz sand is 80 mesh; and the particle size of magnesium hydroxide is 150mm.

[0033] The preparation method of the polymer modifier is as follows: 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution, ultrasonically treated at 60W for 5min, and then stirred with a magnetic stirrer at room temperature for 24h; then, the obtained mixture is centrifuged at a speed of 12000rpm for 10min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24h to obtain a black powder, then, 10g of methyl trifluoroethyl carbonate and 30mL of deionized water are added, and the mixture is continuously shaken at 160°C for 12h, and the precipitate is washed twice with PBS buffer, and weighed after drying at 60°C. The mass concentration of the dopamine hydrochloride solution is 3mg / mL. The polycarboxylic acid water reducer is a polyether polycarboxylic acid water reducer; and the cellulose ether thickener is hydroxyethyl cellulose.

[0034] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0035] Example 3

[0036] The high-efficiency quick-setting pore sealing material comprises the following components, measured in parts by weight: cement matrix: 45 parts, polymer modifier: 12 parts, aluminum sulfate: 3 parts, quartz sand: 20 parts, polycarboxylic acid water reducer: 0.5 parts, magnesium hydroxide: 3 parts, and cellulose ether thickener: 0.1 parts.

[0037] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 200mm; the mesh size of quartz sand is 80 mesh; and the particle size of magnesium hydroxide is 150mm.

[0038] The preparation method of the polymer modifier is as follows: 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution, ultrasonically treated at 60W for 5min, and then stirred with a magnetic stirrer at room temperature for 24h; then, the resulting mixture is centrifuged at a speed of 12000rpm for 10min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24h to obtain a black powder, then, 10g of methyl trifluoroethyl carbonate and 30mL of deionized water are added, and the mixture is continuously shaken at 160°C for 12h, and the precipitate is washed twice with PBS buffer, and weighed after drying at 60°C. The mass concentration of the dopamine hydrochloride solution is 3mg / mL. The polycarboxylic acid water reducer is an amphoteric polycarboxylic acid water reducer; and the cellulose ether thickener is hydroxypropyl methylcellulose.

[0039] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0040] Example 4

[0041] The high-efficiency quick-setting pore sealing material comprises the following components, measured in parts by weight: cement matrix: 55 parts, polymer modifier: 8 parts, aluminum sulfate: 8 parts, quartz sand: 12 parts, polycarboxylic acid water reducer: 2 parts, magnesium hydroxide: 1 part, and cellulose ether thickener: 0.5 parts.

[0042] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 200mm; the mesh size of quartz sand is 120 mesh; and the particle size of magnesium hydroxide is 150mm.

[0043] The preparation method of the polymer modifier is as follows: 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution, ultrasonically treated at 60W for 5min, and then stirred with a magnetic stirrer at room temperature for 24h; then, the resulting mixture is centrifuged at a speed of 12000rpm for 10min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24h to obtain a black powder, then, 10g of methyl trifluoroethyl carbonate and 30mL of deionized water are added, and the mixture is continuously shaken at 160°C for 12h, and the precipitate is washed twice with PBS buffer, and weighed after drying at 60°C. The mass concentration of the dopamine hydrochloride solution is 3mg / mL. The polycarboxylic acid water reducer is a polyester polycarboxylic acid water reducer; and the cellulose ether thickener is ethyl hydroxyethyl cellulose.

[0044] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0045] Example 5

[0046] The high-efficiency quick-setting pore sealing material comprises the following components, measured in parts by weight: cement matrix: 50 parts, polymer modifier: 10 parts, aluminum sulfate: 5 parts, quartz sand: 16 parts, polycarboxylic acid water reducer: 1.5 parts, magnesium hydroxide: 2 parts, and cellulose ether thickener: 0.3 parts.

[0047] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 150mm; the mesh size of quartz sand is 100 mesh; and the particle size of magnesium hydroxide is 100mm.

[0048] The preparation method of the polymer modifier is as follows: 2g of ferric chloride is added to 10.0mL of dopamine hydrochloride solution, ultrasonically treated at 60W for 5min, and then stirred with a magnetic stirrer at room temperature for 24h; then, the resulting mixture is centrifuged at a speed of 12000rpm for 10min, the supernatant is washed twice with deionized water, and freeze-dried in a freeze dryer for 24h to obtain a black powder, then, 10g of methyl trifluoroethyl carbonate and 30mL of deionized water are added, and the mixture is continuously shaken at 160°C for 12h, and the precipitate is washed twice with PBS buffer, and weighed after drying at 60°C. The mass concentration of the dopamine hydrochloride solution is 3mg / mL. The polycarboxylic acid water reducer is a polyester polycarboxylic acid water reducer; and the cellulose ether thickener is hydroxypropyl methylcellulose.

[0049] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing a cement matrix, a polymer modifier, aluminum sulfate, quartz sand, a polycarboxylic acid-based water reducer, magnesium hydroxide, and a cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0050] Comparative Example

[0051] The high-efficiency quick-setting sealing material comprises the following components, measured in parts by weight: cement matrix: 50 parts, aluminum sulfate: 5 parts, quartz sand: 16 parts, polycarboxylic acid water reducer: 1.5 parts, magnesium hydroxide: 2 parts, and cellulose ether thickener: 0.3 parts.

[0052] The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; the particle size of aluminum sulfate is 150mm; the mesh size of quartz sand is 100 mesh; and the particle size of magnesium hydroxide is 100mm.

[0053] The preparation method of the above-mentioned high-efficiency quick-setting sealing material includes the following steps: mixing cement matrix, aluminum sulfate, quartz sand, polycarboxylic acid water reducer, magnesium hydroxide, and cellulose ether thickener, and adding 0.25 times of water, stirring and mixing evenly.

[0054] The test plan is as follows: refer to ASTM C78-16 to test the sealing material, and refer to GB / T 35159-2017 to determine the setting time. The specimen size of the flexural strength test is 40mm×40mm×160mm, and the loading speed is 0.02mm / min. After the flexural strength test, the crushed specimen is subjected to a compressive strength test. The cross-sectional size of the compressive test specimen fixture is 40mm×40mm, the height is 40mm, and the loading rate is 0.12mm / min. The impermeability test is carried out in accordance with the test method for relative permeability coefficient of concrete in SL352-2020. The specimen size of the impermeability test is 80mm in bottom diameter, 70mm in top diameter, and 30mm in height. The test is carried out after curing for 28 days in a standard curing box. The constant pressure is controlled at 0.5MPa during the test, and the duration is 2h; finally, the specimen is taken out and split, the water seepage height of the cross section is recorded, and the relative permeability coefficient is calculated.

[0055] Table 1 Test results

[0056]

[0057] At the same time, the sample of Example 5 (the sample for the flexural strength test) was subjected to a scanning electron microscope test. Figure 1 As shown, it can be seen that the structure is uniform and smooth. The high-efficiency quick-setting pore sealing material prepared by the present invention not only improves the mechanical strength, but also improves the sealing performance and construction efficiency by introducing a polymer modifier. These characteristics make it have significant advantages in applications such as mine gas extraction that require fast and efficient sealing.

[0058] The polymer modifier was removed from the control, and both the flexural strength and the compressive strength decreased significantly. Specifically, the flexural strength: The flexural strength of the control was 6.4MPa, which was about 15% lower than that of Example 5, which was 7.5MPa. This shows that the polymer modifier plays an important role in improving the toughness of the material and resisting bending failure. Compressive strength: The compressive strength of the control was 57.1MPa, while that of Example 5 was 63.1MPa, a decrease of more than 9%. This shows that the polymer modifier not only enhances the overall structural strength of the material, but also improves the density and bearing capacity of the material by improving the microstructure. After removing the polymer modifier, the relative permeability coefficient of the material increased significantly. The polymer modifier reduces the permeability of the material by filling microscopic pores or improving the interfacial bonding of the material. After removal, there are more unfilled pores or cracks inside the material, making it easier for gas or liquid to penetrate. Weakened structural integrity: The high permeability coefficient also reflects that the internal structure of the material is not dense enough, which is consistent with the reduced strength. After removing the polymer modifier, the initial setting time and final setting time were significantly extended, reaching 7800s and 14600s respectively. This indicates that: the setting speed is slowed down: the polymer modifier accelerates the hydration reaction of the cement matrix through chemical reaction or physical doping, thereby shortening the setting time. After removal, the cement matrix lacks sufficient reactivity or catalytic effect. Construction efficiency is reduced: the extended setting time means that in actual application, it takes longer to wait for the material to solidify, which is disadvantageous in emergency construction or rapid sealing scenarios.

[0059] In summary, polymer modifiers play a key role in high-efficiency quick-setting sealing materials. Their main contributions include: Enhanced mechanical properties: By improving the material's flexural and compressive resistance, it exhibits better durability when subjected to external forces. Improved sealing performance: Reduced permeability coefficient, effectively prevented gas or liquid leakage, and improved safety. Accelerated setting process: Shortened initial and final setting time, and improved construction efficiency. Therefore, when developing new sealing materials, the selection and ratio of polymer modifiers should be fully considered to optimize material performance and meet specific application requirements.

[0060] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A high-efficiency quick-setting pore sealing material, characterized in that: In parts by weight, it includes the following components: Cement matrix: 40-60 parts, Polymer modifier: 5-15 parts, Aluminum sulfate: 3-8 parts, Quartz sand: 10-20 parts, Polycarboxylic acid water reducer: 0.5-2 parts, Magnesium hydroxide: 1-3 parts, Cellulose ether thickener: 0.1-0.5 parts.

2. The high-efficiency quick-setting pore sealing material according to claim 1, characterized in that: In parts by weight, it includes the following components: Cement matrix: 45-55 parts, Polymer modifier: 8-12 parts, Aluminum sulfate: 3-8 parts, Quartz sand: 12-20 parts, Polycarboxylic acid water reducer: 0.5-2 parts, Magnesium hydroxide: 1-3 parts, Cellulose ether thickener: 0.1-0.5 parts.

3. The high-efficiency quick-setting pore sealing material according to claim 2, characterized in that: In parts by weight, it includes the following components: Cement matrix: 50 parts, Polymer modifier: 10 parts, Aluminum sulfate: 5 parts, Quartz sand: 16 parts, Polycarboxylic acid water reducing agent: 1.5 parts, Magnesium hydroxide: 2 parts, Cellulose ether thickener: 0.3 parts.

4. The high-efficiency quick-setting pore sealing material according to claim 1, characterized in that: The cement matrix is ​​cement powder with a grade of 52.5 and a specific surface area of ​​300m 2 / kg; The particle size of aluminum sulfate is 100-200 mm; The mesh number of quartz sand is 80-120 mesh; The particle size of magnesium hydroxide is 50-150 mm.

5. The high-efficiency quick-setting pore-sealing material according to claim 4, characterized in that: The preparation method of the polymer modifier is as follows: 2 g of ferric chloride was added to 10.0 mL of dopamine hydrochloride solution, ultrasonically treated at 60 W for 5 min, and then stirred with a magnetic stirrer at room temperature for 24 h; thereafter, the resulting mixture was centrifuged at 12000 rpm for 10 min, the supernatant was washed twice with deionized water, and freeze-dried in a freeze dryer for 24 h to obtain a black powder, then 10 g of methyl trifluoroethyl carbonate and 30 mL of deionized water were added, and the mixture was continuously shaken at 160° C. for 12 h, and the precipitate was washed twice with PBS buffer, dried at 60° C., and weighed to obtain the product.

6. The high-efficiency quick-setting pore-sealing material according to claim 5, characterized in that: The mass concentration of the dopamine hydrochloride solution is 3 mg / mL.

7. The high-efficiency quick-setting pore-sealing material according to claim 6, characterized in that: The polycarboxylic acid water reducer is one of polyester polycarboxylic acid water reducer, polyether polycarboxylic acid water reducer and amphoteric polycarboxylic acid water reducer; The cellulose ether thickener is one of carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and ethyl hydroxyethyl cellulose.

8. The method for preparing a high-efficiency quick-setting pore-sealing material according to claim 1, characterized in that: The steps include: Mix the cement matrix, polymer modifier, aluminum sulfate, quartz sand, polycarboxylic acid water reducer, magnesium hydroxide, and cellulose ether thickener, add 0.25 times of water, and stir to mix evenly.

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