Silicon-modified waterborne epoxy resin air-entraing concrete, preparation method and application thereof

Abstract

The application discloses a kind of silicon-modified waterborne epoxy resin air-tight concrete and preparation method and application, belong to building material technical field, by mass fraction, including following raw materials: 1 portion of cement, 1.5 portion of fine aggregate, 2 portion of coarse aggregate, 0.4 portion of water and silicon-modified waterborne epoxy resin emulsion, the content of silicon-modified waterborne epoxy resin emulsion is 5-15% of cement quality, and water-cement ratio is 0.4-0.5.The application of the above-mentioned silicon-modified waterborne epoxy resin air-tight concrete and preparation method and application, its raw material source is extensive, preparation process controllable, construction performance is good.Its low permeability, high mechanical properties and excellent durability in high-pressure gas environment make it suitable for underground compressed air energy storage chamber, underground hydrogen storage chamber, underground gas storage and other engineering fields with extremely high air-tightness requirements, with significant economic and social benefits.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and its application. Background Technology

[0002] With the advancement of the "dual-carbon" strategy, large-scale energy storage technology has become a key technology supporting the development of the energy industry. Underground compressed air energy storage and underground hydrogen storage have attracted widespread attention due to their advantages such as large capacity and high efficiency. As underground chambers serve as gas storage spaces, their lining materials need to possess good airtightness, mechanical load-bearing capacity, and durability under long-term high gas pressure.

[0003] Traditional cement concrete, due to its high porosity and brittleness, is prone to micro-cracks and gas leakage in high-pressure gas environments. While existing polymer-modified concrete has shown some improvement, the water resistance and impermeability of cured products from ordinary water-based epoxy resins remain insufficient due to the presence of hydrophilic groups in their molecular chains. Furthermore, the effect of polymer dosage on concrete performance is not yet clear, and a systematic optimal mix design is lacking.

[0004] Therefore, developing a new type of concrete material that combines high airtightness, high mechanical properties, and excellent durability is of great significance for underground energy storage projects. Summary of the Invention

[0005] The purpose of this invention is to provide a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and its applications. The raw materials are widely available, the preparation process is controllable, and it exhibits excellent construction performance. Its low permeability, high mechanical properties, and superior durability under high-pressure gas environments make it suitable for engineering fields with extremely high airtightness requirements, such as underground compressed air storage chambers, underground hydrogen storage chambers, and underground gas storage facilities, resulting in significant economic and social benefits.

[0006] To achieve the above objectives, the present invention provides a silicon-modified waterborne epoxy resin airtight concrete, comprising the following raw materials by weight: 1 part cement, 1.5 parts fine aggregate, 2 parts coarse aggregate, 0.4 parts water, and silicon-modified waterborne epoxy resin emulsion, wherein the amount of silicon-modified waterborne epoxy resin emulsion is 5-15% of the cement weight, and the water-cement ratio is 0.4-0.5.

[0007] Preferably, the cement is P.O42.5 ordinary Portland cement, the fine aggregate is natural medium sand with a mud content of ≤12%, and the coarse aggregate is 5-20mm continuously graded crushed stone.

[0008] Preferably, the preparation method of the silicone-modified waterborne epoxy resin emulsion includes the following steps: Step 1: Preparation of silica sol: Tetraethyl orthosilicate, anhydrous ethanol, deionized water and silane coupling agent are mixed and the pH is adjusted. After the reaction, silica sol is obtained. Step 2, graft copolymerization: Mix epoxy resin E-12 and propylene glycol methyl ether, heat and then add the mixed solution dropwise. The mixed solution consists of acrylic acid, butyl acrylate, styrene and benzoyl peroxide. Keep warm after the reaction. Step 3: After the heat preservation is completed, add triphenylphosphine and the silica sol prepared in step 1, and continue the reaction; Step 4, Neutralization and Waterborneization: After the reaction is complete, triethylamine is added for neutralization to obtain a silicone-modified waterborne epoxy resin emulsion.

[0009] Preferably, in step one, the molar ratio of tetraethyl orthosilicate, anhydrous ethanol, deionized water, and silane coupling agent is 1:4:2.2:0.2, the silane coupling agent is KH560, the pH is adjusted to 2-2.5 using hydrochloric acid, the reaction temperature is 55℃, and the reaction time is 5h.

[0010] Preferably, in step two, the amount of epoxy resin E-12 is 100g, the amount of propylene glycol methyl ether is 75mL, the temperature is heated to 100℃, the mass ratio of acrylic acid, butyl acrylate, styrene and benzoyl peroxide is (10~15):(10~15):(5~10):(0.5~1), the reaction is carried out for 2.5-3h, and the temperature is maintained for 3h.

[0011] Preferably, in step three, the amount of triphenylphosphine used is 2g, the mass ratio of epoxy resin E-12 to triphenylphosphine is 50:1, and the reaction time is 1h.

[0012] Preferably, in step four, the amount of triethylamine used is 7 mL, and the neutralization reaction time is 1 h.

[0013] The above-mentioned method for preparing silicon-modified waterborne epoxy resin airtight concrete includes the following steps: S1. Add cement, fine aggregate, and coarse aggregate to a mixer and dry mix evenly. S2. Mix the silicone-modified waterborne epoxy resin emulsion with deionized water until uniform, and then add it to the mixer in S1 for wet mixing to obtain the mixture. S3. Pour the mixture into the mold, vibrate to compact it, smooth the surface, and then cure it.

[0014] Preferably, in S1, the dry mixing time is 2 minutes; In S2, mix wet for 2-3 minutes; In S3, the maintenance is standard maintenance, and the standard maintenance conditions are: temperature 20±2℃, relative humidity ≥95%, and maintenance days of 28 days.

[0015] An application of a silicon-modified waterborne epoxy resin airtight concrete: The aforementioned silicon-modified waterborne epoxy resin airtight concrete is used to prepare the lining structure of underground compressed air energy storage chambers, underground hydrogen storage chambers, or underground gas storage facilities.

[0016] Therefore, the present invention, employing the aforementioned silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and its application, has the following beneficial effects: (1) By using the molecular-level hybrid design of silicon-modified waterborne epoxy resin emulsion, the nano-filling effect of inorganic silica sol is combined with the high adhesion and film-forming properties of organic epoxy resin, so that the modified components can form a chemical bond network simultaneously during the cement hydration process, thereby fundamentally improving the defect of poor interfacial compatibility between traditional polymers and inorganic substrates, and laying a chemical foundation for the comprehensive improvement of concrete performance.

[0017] (2) The siloxane segments in the silicon-modified component undergo hydrophobic grafting on the capillary walls inside the concrete and react with cement hydration products to generate hydrophobic silicate complexes. At the same time, the nano-silica sol particles effectively fill the micron-sized pores, changing the pore structure from a connected open type to a closed isolated type, thereby significantly enhancing the concrete's ability to block high-pressure gases and meeting the stringent requirements for long-term airtightness of lining materials in projects such as underground energy storage chambers.

[0018] (3) Silicon-modified waterborne epoxy resin serves as a flexible polymer to bridge microcracks, improve tensile toughness and tensile-compression ratio, and strengthens the cement stone skeleton through the rigid nanoparticles of silica sol, thus avoiding the strength reduction problem caused by ordinary polymer modification and achieving a synergistic improvement in compressive strength and crack toughness.

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0020] Figure 1 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the complete hydrolysis reaction equation of tetraethyl orthosilicate during the preparation of silicon-modified waterborne epoxy resin emulsion. Figure 2 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the condensation reaction equation for preparing a silicon-modified waterborne epoxy resin emulsion. Figure 3 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the co-condensation reaction equation for preparing silicon-modified waterborne epoxy resin emulsion. Figure 4 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the reaction equation for synthesizing epoxy resin when preparing a silicon-modified waterborne epoxy resin emulsion. Figure 5 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the free radical copolymerization reaction equation during the preparation of silicon-modified waterborne epoxy resin emulsion. Figure 6 This invention relates to a silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and the ring-opening esterification reaction equation for preparing a silicon-modified waterborne epoxy resin emulsion. Figure 7 This invention relates to a method for preparing airtight concrete using silicon-modified waterborne epoxy resin, and an equipment diagram for preparing silicon-modified waterborne epoxy resin emulsion. Detailed Implementation

[0021] The reaction principle for preparing silicone-modified waterborne epoxy resin emulsions is as follows: The sol-gel method is a widely used material preparation method that utilizes metal alkoxides or metal salts as precursors. Through the combined effects of hydrolysis and condensation reactions, a stable gel system with a three-dimensional network structure is gradually formed. During hydrolysis, the precursor first generates nanoscale active particles or polymer segments, forming a sol system. Subsequently, these active units further condense to construct a continuous three-dimensional network that runs through the entire structure, thus completing the sol-gel transformation.

[0022] Tetraethyl orthosilicate is a commonly used silicon precursor, but its hydrolysis rate is relatively slow and usually requires effective regulation under the action of acid or base catalysts. In acid-catalyzed systems, H... + By protonating alkoxy groups, the electrophilic reactivity of silicon atoms was significantly enhanced, resulting in a hydrolysis rate that was significantly higher than the condensation rate; while under alkaline catalysis, OH... - Not only does it participate in hydrolysis as a nucleophile, but it can also rapidly abstract protons from silanol groups to form highly reactive silanolate anions, thus increasing the condensation rate compared to the hydrolysis rate. In an acidic environment, the hydrolysis of tetraethyl orthosilicate follows a stepwise nucleophilic substitution mechanism, sequentially generating intermediates such as (C2H5O)3SiOH, (C2H5O)2Si(OH)2, and (C2H5O)Si(OH)3, ultimately producing orthosilicate Si(OH)3. The corresponding reaction equations are shown in [reference needed]. Figure 1 .

[0023] At the same time, the hydrolysis products of tetraethyl orthosilicate will also undergo Figure 2 The condensation reaction shown.

[0024] Tetraethyl orthosilicate and γ-glycidyl etheroxypropyltrimethoxysilane can undergo concerted hydrolysis to produce silanols and reactive intermediates such as R-Si(OH)3. These hydrolysis products then undergo a condensation reaction (reaction equations are shown in...). Figure 3This process forms a ≡Si-O-Si≡(R) covalent bond structure within the inorganic silicon-oxygen framework, ultimately constructing a structure with R-[Si-O-Si]. n -R characteristic organic-inorganic hybrid system to achieve covalent bonding modification of silica sol.

[0025] The esterification reaction between epoxy resins and fatty acids is a stepwise chemical process, and the progress of the reaction is closely related to the reactivity of the functional groups. Epoxy resin molecules contain two types of active sites: epoxy groups and hydroxyl groups, with the epoxy group exhibiting higher reactivity. Therefore, the carboxyl group in the fatty acid first undergoes a ring-opening reaction with the epoxy group.

[0026] In this reaction, the oxygen atom on the carboxyl group acts as a nucleophile, attacking the less sterically hindered carbon atom on the epoxy ring, causing the epoxy ring to open and generating a hydroxyl ester structure linked by ether bonds, i.e., a half-ester intermediate. No water molecules are generated as a byproduct at this stage, making it a crucial preliminary step in the synthesis of epoxy esters. Subsequently, the remaining carboxyl group in the system can continue to undergo conventional condensation esterification reactions with newly formed hydroxyl groups on the half-ester intermediate or with existing hydroxyl groups in the epoxy resin. The corresponding reaction equations are shown below. Figure 4 .

[0027] Based on the successful synthesis of epoxy ester resin, further... Figure 5 The free radical copolymerization reaction shown is used to modify the resin for hydrophilicity and prepare a waterborne resin. Acrylic monomers are used as grafting units to undergo a free radical graft copolymerization reaction with epoxy ester resin, introducing carboxyl functional groups into the polymer molecular chain. Subsequently, triethylamine is used for neutralization treatment to convert the carboxyl groups into carboxylic acid ammonium salt groups, thereby endowing the resin with excellent water dispersibility and finally obtaining a stable waterborne epoxy resin system.

[0028] To construct an organic-inorganic hybrid structure, epoxy groups are introduced onto the surface of silica sol using silane coupling agents, which then undergo ring-opening esterification with the carboxyl groups on the resin matrix, thereby achieving chemical bonding.

[0029] During the reaction, the carboxyl group acts as a nucleophile, attacking the epoxy ring and inducing ring-opening and ester bond formation, while simultaneously generating new hydroxyl groups. Through this chemical bonding, a stable interfacial bond is formed between the inorganic silicon phase and the organic resin, ultimately yielding a homogeneous silicon-modified waterborne epoxy resin. The corresponding reaction equations are shown below. Figure 6 .

[0030] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims and are all within the protection scope of the present invention.

[0031] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0032] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0033] In this invention, unless otherwise specified, all other test materials and instruments are conventional test materials in the field and can be purchased through commercial channels.

[0034] Example 1 This invention provides a silicon-modified waterborne epoxy resin airtight concrete, which, by weight, comprises the following raw materials: 1 part cement, 1.5 parts fine aggregate, 2 parts coarse aggregate, 0.4 parts water, and silicon-modified waterborne epoxy resin emulsion. The amount of silicon-modified waterborne epoxy resin emulsion is 10% of the cement weight, and the water-cement ratio is 0.4.

[0035] The cement is P.O42.5 ordinary Portland cement, the fine aggregate is natural medium sand with a mud content of 12%, and the coarse aggregate is 5-20mm continuously graded crushed stone.

[0036] When preparing silicone-modified waterborne epoxy resin emulsions, the following methods are used: Figure 7 The apparatus shown is prepared by the following steps: Step 1: Preparation of silica sol: Tetraethyl orthosilicate, anhydrous ethanol, deionized water and silane coupling agent KH560 are mixed in a molar ratio of 1:4:2.2:0.2, and the pH is adjusted to 2.5 with hydrochloric acid. After reacting at 55°C for 5 hours, silica sol is obtained.

[0037] Step 2, graft copolymerization: Mix 100g of epoxy resin E-12 and 75mL of propylene glycol methyl ether, heat to 100℃ and then add the mixed solution dropwise. The mixed solution is composed of acrylic acid, butyl acrylate, styrene and benzoyl peroxide in a mass ratio of 12:12:8:0.6. The addition is completed in 3 hours, and the reaction is kept at the temperature for 3 hours afterward.

[0038] Step 3: After the heat preservation is completed, add 2g of triphenylphosphine and the silica sol prepared in step 1, and continue the reaction for 1 hour.

[0039] Step 4, Neutralization and Waterborneization: After the reaction is complete, add 7 mL of triethylamine for neutralization to obtain a pale yellow uniform emulsion with a solid content ≥40% and a viscosity ≤5 Pa·s, which is the silicone-modified waterborne epoxy resin emulsion.

[0040] The above-mentioned method for preparing silicon-modified waterborne epoxy resin airtight concrete includes the following steps: S1. Add cement, fine aggregate, and coarse aggregate to the mixer and dry mix for 2 minutes until evenly mixed. S2. Mix the silicone-modified waterborne epoxy resin emulsion with deionized water until uniform, then add it to the mixer in S1 and wet mix for 2 minutes to obtain the mixture. S3. Pour the mixture into a 100mm×100mm×100mm mold, vibrate to compact, smooth the surface, and cure. The curing is standard curing, and the standard curing conditions are: temperature 20±2℃, relative humidity ≥95%, and curing days of 28 days.

[0041] Example 2 The only difference between this embodiment and Embodiment 1 is that the dosage of the silicon-modified waterborne epoxy resin emulsion is 15% of the cement mass; all other conditions are the same.

[0042] Comparative Example 1 The only difference between this comparative example and Example 1 is that the silicone-modified waterborne epoxy resin emulsion in the raw materials was replaced with commercially available ordinary waterborne epoxy resin; all other conditions were the same.

[0043] Comparative Example 2 The only difference between this comparative example and Example 1 is that the raw materials do not contain silicone-modified waterborne epoxy resin emulsion; all other conditions are the same.

[0044] The products prepared in Examples 1-2 and Comparative Examples 1-2 were subjected to performance tests, and the test results are shown in Table 1.

[0045] Table 1 Test Results

[0046] Comparative analysis of the mechanical, physical, and durability performance test data of the four mix proportions showed that the silicon-modified waterborne epoxy resin concrete exhibited the best comprehensive performance at a dosage of 10% and a water-cement ratio of 0.4. In terms of mechanical properties, the 28-day compressive strength of this mix proportion (Example 1) reached 38.96 MPa, the splitting tensile strength was 4.6 MPa, and the tension-to-compression ratio was 0.1181, all significantly higher than those of Example 2 (37.65 MPa, 4.0 MPa, 0.1062), Comparative Example 1 (37.48 MPa, 3.7 MPa, 0.0987), and Comparative Example 2 (34.43 MPa, 3.3 MPa, 0.0958), demonstrating that it possesses both the highest strength and optimal toughness.

[0047] In terms of physical properties, Example 1 had the lowest saturation coefficient (0.716) and porosity (10.6%) among the four groups, indicating that its internal pore structure was the densest and had the fewest interconnected pores. Regarding durability, Example 1 had the lowest gas permeability coefficient (0.36 × 10⁻⁶). -6 The permeability (cm / s) was reduced by 78% compared to Comparative Example 1 and by 89% compared to Comparative Example 2; the carbonization depth at 28 days (9.22 mm) was the lowest; the electrical flux (419.48 C) was at a "very low" permeability level; and the sulfate resistance coefficient (64.7%) was also better than that of the ordinary modified group and the reference group.

[0048] Overall, although the 15% silicon-modified waterborne epoxy resin emulsion in Example 2 is slightly superior in terms of gas permeability, sulfate resistance, and chloride ion resistance (e.g., gas permeability coefficient 0.26 × 10⁻⁶), -6 While the epoxy resin exhibits a high strength (cm / s) and corrosion resistance coefficient of 85.1%, its compressive strength, tensile strength, tensile-compression ratio, and carbonation resistance are all lower than those of a 10% content. Furthermore, increasing the silicon-modified waterborne epoxy resin emulsion by 50% leads to a decrease in mechanical properties and reduced economic efficiency. In contrast, a 10% silicon-modified content maintains excellent durability (airtightness fully meets engineering requirements) while achieving peak mechanical properties and the densest microstructure, resulting in the best overall benefits. Therefore, a 10% silicon-modified waterborne epoxy resin content and a water-cement ratio of 0.4 are determined to be the optimal formulation, particularly suitable for lining projects with high airtightness and durability requirements, such as underground energy storage chambers.

[0049] Furthermore, Table 1 shows that Examples 1 and 2, which use silicon-modified waterborne epoxy resin, are superior to Comparative Examples 1 and 2 in terms of mechanical, physical, and durability indicators. This directly proves that the silicon-modified component and the cement-based material are not simply physically mixed, but achieve a significant synergistic enhancement effect through chemical bonding and microstructure regulation.

[0050] Firstly, in terms of mechanical properties, the 28-day compressive strength, splitting tensile strength, and tensile-compression ratio of Example 1 are all higher than those of Comparative Example 1 and Comparative Example 2, while its porosity and water saturation coefficient are the lowest among the four groups. This indicates that the organic-inorganic hybrid network formed by the nano-SiO2 in the silica sol and the epoxy resin can effectively fill the capillary pores of cement stone and chemically bond with the CSH gel, making the interfacial transition zone denser, thereby synergistically improving strength and toughness. Ordinary waterborne epoxy, due to its large number of hydrophilic groups and poor film water resistance, cannot achieve the same effect.

[0051] Secondly, regarding airtightness and durability, the gas permeability coefficient of Example 1 was reduced by 78% compared to Comparative Example 1 and by 89% compared to Comparative Example 2; the electrical flux was significantly lower than that of Comparative Example 1 and Comparative Example 2, and the sulfate resistance coefficient was also significantly better than the latter two. This indicates that the siloxane segments in the silicon-modified component can not only form a hydrophobic film, but also undergo secondary reactions with cement hydration products (such as ettringite and calcium hydroxide) to generate silicate complexes, synergistically sealing gas permeation channels. Ordinary epoxy lacks this chemical affinity, hence its barrier effect is significantly inferior.

[0052] Furthermore, the preparation process of the silicon-modified waterborne epoxy emulsion itself demonstrates deep synergy between the steps: first, silica sol is prepared by hydrolysis and condensation of tetraethyl orthosilicate and KH560 silane coupling agent is introduced; then, epoxy resin E-12 is grafted and copolymerized with monomers such as acrylic acid to introduce carboxyl groups; subsequently, the silanol groups on the surface of the silica sol undergo esterification condensation with epoxy groups under triphenylphosphine catalysis; finally, triethylamine is used to neutralize and form a salt to achieve waterborne properties. This sequence ensures that the siloxane groups are chemically bonded to the epoxy molecular chain to form a homogeneous hybrid emulsion. If any step is missing (such as the direct use of ordinary waterborne epoxy in Comparative Example 1), stable nanoscale dispersion and continuous secondary crosslinking cannot be formed in concrete, as strongly evidenced by the performance differences shown in Table 1.

[0053] Finally, although Example 2 was slightly better than Example 1 in terms of gas permeability and sulfate resistance, its compressive strength, tensile strength, tensile-compressive ratio, and carbonation resistance all decreased. Furthermore, a 30% increase in polymer content led to a deterioration in mechanical properties, indicating that there is an optimal dosage window (10%) for the synergistic effect of the silicon-modified components. This non-monotonicity precisely confirms that the synergistic effect originates from a chemical reaction. Excessive polymer can encapsulate cement particles, hinder hydration, or agglomerate, damaging the inorganic skeleton. Physical filler modifiers typically do not exhibit the phenomenon of strength reduction due to "over-doping," thus conversely proving that there is indeed a genuine chemical synergy between the silicon-modified system and the cement matrix.

[0054] In summary, the data in Table 1 confirms from multiple dimensions that the silica-modified waterborne epoxy resin airtight concrete of this invention achieves triple synergy between silica sol, epoxy resin and cement hydration products through a molecular-level hybrid preparation process, including nanofilling, interfacial chemical bonding and hydrophobic film formation. Ultimately, at the optimal dosage, it obtains mechanical properties, dense pore structure and ultra-high airtightness far superior to ordinary modified concrete, making it particularly suitable for harsh environments such as underground energy storage chambers.

[0055] Therefore, this invention utilizes the aforementioned silicon-modified waterborne epoxy resin airtight concrete, its preparation method, and its application. The raw materials are widely available, the preparation process is controllable, and the construction performance is excellent. Its low permeability, high mechanical properties, and superior durability under high-pressure gas environments make it suitable for engineering fields with extremely high airtightness requirements, such as underground compressed air storage chambers, underground hydrogen storage chambers, and underground gas storage facilities, resulting in significant economic and social benefits.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A silicon-modified waterborne epoxy resin airtight concrete, characterized in that: By weight, it includes the following raw materials: 1 part cement, 1.5 parts fine aggregate, 2 parts coarse aggregate, 0.4 parts water, and silicon-modified waterborne epoxy resin emulsion. The amount of silicon-modified waterborne epoxy resin emulsion is 5-15% of the cement weight, and the water-cement ratio is 0.4-0.

5.

2. The silicon-modified waterborne epoxy resin airtight concrete according to claim 1, characterized in that: The cement is P.O42.5 ordinary Portland cement, the fine aggregate is natural medium sand with a mud content of ≤12%, and the coarse aggregate is 5-20mm continuously graded crushed stone.

3. The silicon-modified waterborne epoxy resin airtight concrete according to claim 1, characterized in that: The preparation method of silicone-modified waterborne epoxy resin emulsion includes the following steps: Step 1: Preparation of silica sol: Tetraethyl orthosilicate, anhydrous ethanol, deionized water and silane coupling agent are mixed and the pH is adjusted. After the reaction, silica sol is obtained. Step 2, graft copolymerization: Mix epoxy resin E-12 and propylene glycol methyl ether, heat and then add the mixed solution dropwise. The mixed solution consists of acrylic acid, butyl acrylate, styrene and benzoyl peroxide. Keep warm after the reaction. Step 3: After the heat preservation is completed, add triphenylphosphine and the silica sol prepared in step 1, and continue the reaction; Step 4, Neutralization and Waterborneization: After the reaction is complete, triethylamine is added for neutralization to obtain a silicone-modified waterborne epoxy resin emulsion.

4. The silicon-modified waterborne epoxy resin airtight concrete according to claim 3, characterized in that: In step one, the molar ratio of tetraethyl orthosilicate, anhydrous ethanol, deionized water, and silane coupling agent is 1:4:2.2:0.2, the silane coupling agent is KH560, the pH is adjusted to 2-2.5 using hydrochloric acid, the reaction temperature is 55℃, and the reaction time is 5h.

5. The silicon-modified waterborne epoxy resin airtight concrete according to claim 3, characterized in that: In step two, the amount of epoxy resin E-12 is 100g, the amount of propylene glycol methyl ether is 75mL, the temperature is heated to 100℃, and the mass ratio of acrylic acid, butyl acrylate, styrene and benzoyl peroxide is (10~15):(10~15):(5~10):(0.5~1). The reaction is carried out for 2.5-3h and kept at the temperature for 3h.

6. The silicon-modified waterborne epoxy resin airtight concrete according to claim 3, characterized in that: In step three, the amount of triphenylphosphine used is 2g, the mass ratio of epoxy resin E-12 to triphenylphosphine is 50:1, and the reaction time is 1h.

7. The silicon-modified waterborne epoxy resin airtight concrete according to claim 3, characterized in that: In step four, the amount of triethylamine used is 7 mL, and the neutralization reaction time is 1 h.

8. A method for preparing silicon-modified waterborne epoxy resin airtight concrete as described in any one of claims 1-7, characterized in that: Includes the following steps: S1. Add cement, fine aggregate, and coarse aggregate to a mixer and dry mix evenly. S2. Mix the silicone-modified waterborne epoxy resin emulsion with deionized water until uniform, and then add it to the mixer in S1 for wet mixing to obtain the mixture. S3. Pour the mixture into the mold, vibrate to compact it, smooth the surface, and then cure it.

9. The method for preparing silicon-modified waterborne epoxy resin airtight concrete according to claim 8, characterized in that: In S1, the dry mixing time is 2 minutes; In S2, mix wet for 2-3 minutes; In S3, the maintenance is standard maintenance, and the standard maintenance conditions are: temperature 20±2℃, relative humidity ≥95%, and maintenance days of 28 days.

10. An application of silicon-modified waterborne epoxy resin airtight concrete, characterized in that: The silicon-modified waterborne epoxy resin airtight concrete according to any one of claims 1-7 is used to prepare the lining structure of underground compressed air energy storage chambers, underground hydrogen storage chambers or underground gas storage facilities.

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