A hybrid polymer gel material for treating water leakage and its preparation method

Abstract

This invention relates to the field of chemical grouting materials technology, specifically to a hybrid polymer gel leakage control material and its preparation method, comprising three components: a hybrid polymer aqueous solution, a accelerator triethanolamine, and an initiator sodium persulfate. The hybrid polymer aqueous solution is prepared using deionized water, light magnesium oxide, zinc oxide, acrylic acid, and a self-made crosslinking agent. An intermediate is obtained by esterification reaction of pentaerythritol and 3,4-dihydroxybenzoic acid, and the self-made crosslinking agent is obtained by reacting the intermediate with acryloyl chloride. The hybrid polymer gel leakage control material exhibits extremely high bulk strength, and its drying shrinkage rate can be reduced to below 10%.

Description

Technical Field

[0001] This invention belongs to the field of chemical grouting materials technology, specifically relating to a modification technology of acrylate grouting materials, and particularly to a hybrid polymer gel leakage control material and its preparation method. Background Technology

[0002] Traffic tunnels, underground utility tunnels, underground spaces in commercial complexes, and underpasses have been put into use and operation year by year. During the construction and service of these facilities, various factors have led to through-cracks in the concrete structure or leaks in the expansion joints of underground projects, causing inconvenience and reducing comfort. Therefore, grouting is often required for repairs. Currently, grouting materials used on the market include epoxy resin, polyurethane, and acrylate materials. Epoxy resin materials, due to their high strength, are used for projects requiring reinforcement. However, because epoxy resin grout is an oil-based system, it is difficult to bond in damp areas where water seeps, making these areas weak points for future re-leakage. Polyurethane grouting materials are divided into oil-based and water-based polyurethane grouts, used for projects involving expansion joints or sudden gushing. Oil-based polyurethane grout foams rapidly upon contact with water during construction; while water-based polyurethane grout solidifies into a gel upon contact with water, encapsulating the water within the gel. However, due to the high internal porosity and lack of flexibility of oil-based polyurethane foam, the foam is prone to damage during later structural deformation and settling, resulting in a high re-leakage rate and questionable repair effectiveness. Water-based polyurethane has poor dry and wet cycle performance. Traditional acrylate materials are typically produced by free radical polymerization of monomers such as magnesium acrylate and zinc acrylate in aqueous solutions. Due to their low viscosity, good pourability, non-toxicity, environmental friendliness, adjustable gel time, high elasticity, and adhesion to damp substrates, their market prospects are attracting considerable attention.

[0003] However, acrylate grouting materials have low solidified body strength and low compressive strength. In the industry standard JC / T 2037-2010 for acrylate grouting fluids, they are divided into Type I and Type II. Type I has a solidified sand body compressive strength ≥200kPa, and Type II has a solidified sand body compressive strength ≥400kPa. Therefore, current acrylate grouting materials on the market have the following defects:

[0004] 1. Insufficient bulk strength: a single ionic bond (Mg) 2+ or Zn 2+ With -COO - The limited strength of the cross-linked network results in low mechanical properties of the gel (such as compressive and shear strength), making it difficult to withstand high hydraulic impacts or mechanical loads.

[0005] 2. High drying shrinkage rate: After the gel loses water, the polymer network shrinks significantly, which can easily lead to shrinkage cracks, resulting in sealing failure and secondary leakage.

[0006] To address these issues, existing patents and technologies often employ the addition of inorganic fillers (such as nano-clay, silica fume, gypsum, and cement) or conventional crosslinking agents (such as N,N'-methylenebisacrylamide, or MBA). However, these methods have limitations: while fillers can improve the compressive strength of the solidified sand, adding powder increases the viscosity of the slurry, affecting its flowability and injectability; MBA provides only a single, rigid covalent crosslink, which, while improving strength, often makes the material brittle and has limited effectiveness in solving drying shrinkage problems. Furthermore, MBA has a certain degree of toxicity, impacting the environment. Although some low-toxicity crosslinking agents exist, such as polyethylene glycol diacrylate, the overall strength remains low, limiting comprehensive performance.

[0007] Therefore, developing an innovative technology that can simultaneously and significantly improve bulk strength and suppress drying shrinkage has significant engineering value and market potential. Summary of the Invention

[0008] This invention aims to overcome the shortcomings of existing technologies and provide a novel acrylate grouting material and its preparation method. By introducing a self-designed multifunctional crosslinking agent, this invention simultaneously achieves a significant increase in the material's bulk strength and a substantial reduction in drying shrinkage.

[0009] To achieve the above objectives, in a first aspect, the present invention provides a crosslinking agent comprising the following components:

[0010] .

[0011] The method for synthesizing and preparing the crosslinking agent includes the following steps:

[0012] S1: Install and secure the four-port glass reaction apparatus, equipped with a mechanical stirrer, thermometer, water separator, reflux condenser, and nitrogen inlet, in the heating jacket, ensuring all interfaces are well sealed; first add toluene solvent to the reaction vessel, then add pentaerythritol, 3,4-dihydroxybenzoic acid, and p-toluenesulfonic acid in sequence, with a molar ratio of 1:4.2~5.0:0.06~0.10; turn on nitrogen protection and continuously purge the reaction system at a flow rate of 50 sccm to replace the air; turn on the stirrer and set the speed to 200 rpm to ensure the solids are fully and uniformly suspended in toluene;

[0013] S2: Gradually increase the stirring speed from 200 rpm to 400 rpm to ensure mixing, while slowly heating the temperature to and maintaining the reflux temperature of 115±5℃. Stir at a constant speed to ensure the esterification reaction lasts 8–12 hours. Collect the water generated during the reaction using a water separator. The reaction is considered complete when the water level in the separator no longer increases. The reactants in this step are labeled as intermediate M1. During the esterification reaction, 3,4-dihydroxybenzoic acid is in excess to ensure that all hydroxyl groups in pentaerythritol participate in the esterification process. However, due to factors such as stirring rate and slow heating, intermediate M1 may not be a single final product, but rather a mixture of hydroxyl groups at different positions in pentaerythritol that have been substituted. By controlling the proportion of reactants and the reaction time, the hydroxyl groups of pentaerythritol can be substituted as much as possible.

[0014] The reaction equation for the substitution of four hydroxyl groups in pentaerythritol:

[0015]

[0016] The structural formula of M1, obtained by substituting all four hydroxyl groups of pentaerythritol, is as follows:

[0017]

[0018] S3: After the S2 reaction is complete, turn on the cooling water circulation system to cool the temperature inside the reaction apparatus to below 40°C; then transfer intermediate M1 to a separatory funnel and use 5% (w / w) [a specific solution / method]. Wash the aqueous phase with sodium bicarbonate solution until it is neutral to neutralize the catalyst p-toluenesulfonic acid and excess 3,4-dihydroxybenzoic acid; then wash the organic phase (toluene layer) with deionized water to remove residual inorganic salts (sodium bicarbonate); transfer the organic phase to a clean flask, add sufficient anhydrous magnesium sulfate, stir for 30 minutes to dry; filter to remove the drying agent anhydrous magnesium sulfate, and then use a rotary evaporator to distill under reduced pressure at a water bath temperature of 65°C to completely remove the toluene solvent, obtaining intermediate M2; since intermediate M1 obtained in the esterification reaction may not be a single final product, but a mixture of hydroxyl groups at different positions of pentaerythritol after substitution, intermediate M2 after removing impurities (such as raw materials that did not participate in the reaction, inorganic salts added during washing, etc.) and solvent in step S3 may also not be a single final product, but a mixture of hydroxyl groups at different positions of pentaerythritol after substitution, mainly the organic compound obtained by replacing all four hydroxyl groups of pentaerythritol;

[0019] S4: Install and fix the four-port glass reaction apparatus (reactor) in a low-temperature constant-temperature reaction bath. First, add anhydrous tetrahydrofuran solvent to the reactor, then add intermediate M2, triethylamine, and the polymerization inhibitor p-methoxyphenol, with a molar ratio of 1:9~10:0.003~0.005. Turn on the stirrer and set the speed to 300 rpm to completely dissolve intermediate M2. Set the reaction bath temperature to 0℃ and wait for the reaction solution temperature to drop to 0~5℃. Continuously purge with nitrogen gas at a flow rate of 50 sccm. Add acryloyl chloride in a constant-pressure dropping funnel, with a molar ratio of acryloyl chloride to M2 of 8.8~9.0:1. Finally, add a certain amount of anhydrous tetrahydrofuran for dilution.

[0020] S5: Keep the stirrer running at a constant speed and begin slowly adding the mixture of acryloyl chloride and anhydrous tetrahydrofuran at a dropping rate of 1.0 mL / min. Maintain the reaction solution temperature between 0 and 5°C during the addition process. After the addition is complete, maintain the acrylation reaction at 0–5°C for 1–2 hours. Then remove the ice bath and allow the reaction mixture to slowly and naturally warm to room temperature, continuing to stir for at least 12 hours. The reaction mechanism is as follows:

[0021]

[0022] Acryloyl chloride is in excess relative to intermediate M2, thereby allowing the hydroxyl groups of intermediate M2 to participate in the acrylation reaction as much as possible;

[0023] S6: After the acrylation reaction is completed, the reaction solution is filtered through a Buchner funnel to remove the white solid triethylamine hydrochloride produced. The filter cake is washed with a small amount of anhydrous tetrahydrofuran. The filtrate is transferred to a separatory funnel and washed with a 5% (w / w) hydrochloric acid aqueous solution pre-cooled to 0°C to remove excess triethylamine. The product is then washed with a 5% (w / w) sodium bicarbonate solution pre-cooled to 0°C to neutralize excess hydrochloric acid and acryloyl chloride, and finally washed once with saturated brine pre-cooled to 0°C. The organic phase is transferred to a clean flask, and sufficient anhydrous magnesium sulfate is added for drying for 1 hour. The desiccant, anhydrous magnesium sulfate, is removed by filtration, and the product is concentrated on a rotary evaporator. The temperature of this process must be controlled below 35°C. Under light-protected conditions, most of the anhydrous tetrahydrofuran solvent is removed by vacuum distillation to obtain a viscous product. The viscous product is then transferred to a vacuum drying oven, and under room temperature and light-protected conditions, residual trace solvents and volatile impurities are removed for 24 hours to obtain the final product, pentaerythritol tetrakis(3,4-diacetoxybenzoic acid) crosslinking agent. Since the intermediates M1 and M2 at the front end may be a mixture, the final product may also be a mixture of several different hydroxyl substitution numbers, with pentaerythritol tetrakis(3,4-diacetoxybenzoic acid) as the main component.

[0024]

[0025] Pentaerythritol tetrakis(3,4-disacryloyloxybenzoic acid) ester

[0026] Secondly, the present invention provides a hybrid polymer gel material for treating water leakage, which is prepared from the following materials in parts by weight:

[0027] 100 parts of hybrid polymer aqueous solution,

[0028] Accelerator: Triethanolamine 0.1–10 parts

[0029] Initiator: Sodium persulfate 0.1–10 parts;

[0030] The hybrid polymer aqueous solution is prepared from the following materials in parts by weight:

[0031] 100 parts deionized water

[0032] 1-20 parts of light magnesium oxide,

[0033] 0-20 parts of zinc oxide

[0034] 10-50 parts acrylic acid

[0035] Crosslinking agent pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) ester 0.1 to 6 parts.

[0036] Preferably, the hybrid polymer gel leakage control material comprises the following three components by weight:

[0037] 100 parts of hybrid polymer aqueous solution,

[0038] Accelerator: Triethanolamine 0.1–10 parts

[0039] Initiator: Sodium persulfate 0.1–10 parts;

[0040] The hybrid polymer aqueous solution is prepared from raw materials including the following materials, calculated by weight:

[0041] 100 parts deionized water

[0042] 5-10 parts of light magnesium oxide,

[0043] 4-10 parts zinc oxide

[0044] 30-40 parts acrylic acid

[0045] Crosslinking agent pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) ester 2 to 6 parts.

[0046] A further technical solution is that the hybrid polymer gel leakage treatment material, calculated by weight, includes the following three components:

[0047] 100 parts of hybrid polymer aqueous solution,

[0048] Accelerator: 0.5–2 parts triethanolamine

[0049] Sodium persulfate initiator: 0.5–2 parts;

[0050] The hybrid polymer aqueous solution, calculated by weight, is prepared from raw materials including the following:

[0051] 100 parts deionized water

[0052] 5-10 parts of light magnesium oxide,

[0053] 4-10 parts zinc oxide

[0054] 30-40 parts acrylic acid

[0055] Crosslinking agent pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) ester 2 to 6 parts.

[0056] The preparation method of the hybrid polymer gel leakage treatment material includes the following steps:

[0057] S1: Add 100 parts of deionized water to the reactor, turn on the stirrer, and control the stirring speed at 80-120 rpm; under stirring conditions, add 1-20 parts of light magnesium oxide and 0-20 parts of zinc oxide to the reactor, and mix the powder with deionized water thoroughly to form a suspension.

[0058] S2: Turn on the cold water circulation system and start titrating 10-50 parts of acrylic acid into the reactor; since the acid-base neutralization reaction is exothermic, in order to avoid explosive polymerization, control the temperature inside the reactor to be below 50°C; continue the reaction for 4-6 hours, stirring until the acid-base neutralization reaction is completely finished, to obtain a transparent solution of one or a mixture of two monomers of magnesium acrylate and zinc acrylate, i.e., an aqueous solution of acrylate, with the pH controlled in the range of 6.0-9.0;

[0059] S3: After the above-prepared acrylate aqueous solution is filtered through precipitation, it is added to a high-speed dispersion vessel and the rotation speed is controlled at 1000-1200 rpm; then 0.1-5 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent are added and stirred for 15-30 minutes until completely mixed.

[0060] S4: Weigh out 0.1 to 10 parts of triethanolamine as an accelerator;

[0061] S5: Weigh out 0.1 to 10 parts of sodium persulfate as an initiator.

[0062] Compared with the prior art, the outstanding advantages and beneficial effects of the present invention are as follows:

[0063] 1. Improved bulk strength: The hybrid polymer gel leakage treatment material uses a novel crosslinking agent with multiple acryloyl groups. These multiple acryloyl groups participate in crosslinking, enabling the material to form a strong covalent crosslinking network after curing, thus giving the material extremely high bulk strength.

[0064] 2. Reduced drying shrinkage: The hybrid polymer gel leakage treatment material prepared by this invention, with the optimal formulation, can increase the compressive strength of the solid sand body of the gel by more than 200% compared with traditional materials, and reduce the drying shrinkage to below 10%. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0066] Synthesis and preparation examples of crosslinking agents

[0067] S1: Install and secure the four-necked glass reactor within the heating mantle. First, add 150 ml of toluene solvent, then add 13.6 g of pentaerythritol, 69.36 g of 3,4-dihydroxybenzoic acid, and 1 g of p-toluenesulfonic acid sequentially. Turn on nitrogen protection and continuously purge the reaction system at a flow rate of 50 sccm to replace the air. Turn on the stirrer and set the speed to 200 rpm to ensure the solids are fully and uniformly suspended in the toluene.

[0068] S2: Gradually increase the stirring speed from 200 rpm to 400 rpm, while slowly heating the temperature to and maintaining it between 110 and 120°C (reflux temperature). Stir at a constant speed to ensure the reaction lasts for 8 hours. Collect the water produced in the reaction using a water separator. When the amount of water in the separator is close to the theoretical value and no longer increases, the reaction is considered complete. The reactant in this step is labeled as intermediate M1.

[0069] S3: Turn on the cooling water circulation system to cool the reaction apparatus to below 40°C. Then transfer intermediate M1 to a separatory funnel and wash it three times with approximately 100 mL of 5% (w / w) sodium bicarbonate aqueous solution until the aqueous phase is neutral to neutralize the catalyst p-toluenesulfonic acid and excess 3,4-dihydroxybenzoic acid. Wash the organic phase (toluene layer) twice with deionized water, approximately 100 mL each time, to remove residual inorganic salts. Transfer the organic phase to a clean flask, add sufficient anhydrous magnesium sulfate, and stir for 30 minutes to dry. After filtering to remove the drying agent, use a rotary evaporator to distill under reduced pressure at a water bath temperature of 65°C to completely remove the toluene solvent, obtaining the purified intermediate M2.

[0070] S4: Install and fix the four-necked glass reaction apparatus in a low-temperature constant-temperature reaction bath. First, add 120 mL of anhydrous tetrahydrofuran to the reaction vessel, then add 68 g of intermediate M2 obtained in step S3, 91 g of triethylamine, and 0.04 g of the polymerization inhibitor p-methoxyphenol. Start stirring and set the speed to 300 rpm to ensure the intermediate is completely dissolved and dispersed in the solvent. Set the reaction bath temperature to 0°C and wait for the reaction solution temperature to drop to 0–5°C. Continuously purge with nitrogen gas at a flow rate of 50 sccm, add 80 g of acryloyl chloride to a constant-pressure dropping funnel, and finally add 20 mL of anhydrous tetrahydrofuran for dilution.

[0071] S5: While maintaining continuous and uniform stirring, begin slowly adding the mixture of acryloyl chloride and anhydrous tetrahydrofuran dropwise at a rate of 1.0 mL / min. Maintain the reaction solution temperature between 0 and 5°C during the addition process. After the addition is complete, continue the reaction at 0–5°C for 1 hour. Then remove the ice bath and allow the reaction mixture to slowly and naturally warm to room temperature, continuing stirring for 12 hours.

[0072] S6: Filter the reaction solution through a Buchner funnel to remove the resulting white solid triethylamine hydrochloride. Wash the filter cake with a small amount of anhydrous tetrahydrofuran. Transfer the filtrate to a separatory funnel and wash it twice with approximately 100 mL of 5% (w / w) hydrochloric acid solution pre-cooled to 0°C to remove excess triethylamine. Wash it twice more with approximately 100 mL of 5% (w / w) sodium bicarbonate solution pre-cooled to 0°C to neutralize excess hydrochloric acid and acryloyl chloride. Finally, wash it once with approximately 100 mL of pre-cooled saturated brine. Transfer the organic phase to a clean flask, add sufficient anhydrous magnesium sulfate, and dry for 1 hour. Filter to remove the drying agent, and concentrate the product using a rotary evaporator. The temperature must be controlled below 35°C during this process. Remove most of the anhydrous tetrahydrofuran solvent by vacuum distillation under dark conditions to obtain a viscous product. The viscous product was transferred to a vacuum drying oven and dried at room temperature and in the dark to remove residual trace solvents and volatile impurities for 24 hours to obtain the final product, pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent.

[0073] Example 1:

[0074] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 4.4 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 15.6 parts of acrylic acid into the reactor. Control the temperature inside the reactor to below 50℃ and continue the reaction for 5 hours, maintaining the pH within the range of 6.0–7.0. After precipitation and filtration, the obtained acrylate aqueous solution is added to a high-speed dispersion vessel, with the speed controlled at 1000–1200 rpm. Then, add 0.5 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent, stirring for 15–30 minutes until completely dissolved and mixed evenly to obtain a hybrid polymer aqueous solution. Take 100 parts of the hybrid polymer aqueous solution obtained in this example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0075] Comparative Example 1: Without the use of pentaerythritol tetrakis(3,4-disacryloyloxybenzoic acid) crosslinking agent

[0076] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 4.4 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 15.6 parts of acrylic acid into the reactor. Control the temperature inside the reactor below 50℃ and continue the reaction for 5 hours, maintaining the pH within the range of 6.0–7.0 to obtain an acrylate aqueous solution. Take 100 parts of the acrylate aqueous solution prepared in this comparative example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0077] Example 2:

[0078] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 6.5 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 22 parts of acrylic acid into the reactor. Control the temperature inside the reactor to below 50℃ and continue the reaction for 5 hours, maintaining the pH within the range of 6.0–9.0. After precipitation and filtration, the obtained acrylate aqueous solution is added to a high-speed dispersion vessel, with the rotation speed controlled at 1000–1200 rpm. Then, add 1.2 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent, stirring for 15–30 minutes until completely dissolved and mixed evenly to obtain a hybrid polymer aqueous solution. Take 100 parts of the hybrid polymer aqueous solution obtained in this example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0079] Comparative Example 2: Using polyethylene glycol diacrylate crosslinking agent

[0080] Add 100 parts of deionized water to the reactor and turn on the stirrer at a speed of 80 rpm. While stirring, add 6.5 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 22 parts of acrylic acid into the reactor. Maintain the temperature inside the reactor below 50°C and continue the reaction for 5 hours, keeping the pH between 6.0 and 9.0. After precipitating and filtering the prepared acrylate aqueous solution, add it to a high-speed dispersion vessel at a speed of 1000–1200 rpm. Then, add 1.2 parts of polyethylene glycol diacrylate crosslinking agent and stir for 15–30 minutes until completely dissolved and mixed evenly to obtain a polymer aqueous solution. Take 100 parts of the polymer aqueous solution prepared in this comparative example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0081] Example 3:

[0082] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 9.8 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 35 parts of acrylic acid into the reactor. Control the temperature inside the reactor to below 50℃ and continue the reaction for 5 hours, maintaining the pH within the range of 6.0–9.0. After precipitating and filtering the obtained acrylate aqueous solution, add it to a high-speed dispersion vessel, controlling the rotation speed at 1000–1200 rpm. Then add 2.9 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent, stirring for 15–30 minutes until completely dissolved and mixed evenly to obtain a hybrid polymer aqueous solution. Take 100 parts of the hybrid polymer aqueous solution obtained in this example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0083] Comparative Example 3: The amount of light magnesium oxide was increased, i.e., the acrylate concentration was increased, and the type of crosslinking agent was also changed.

[0084] Add 100 parts of deionized water to the reactor and turn on the stirrer at a speed of 80 rpm. While stirring, add 9.8 parts of light magnesium oxide to the reactor, thoroughly mixing the powder with the deionized water to form a suspension. Then, titrate 35 parts of acrylic acid into the reactor. Maintain the temperature inside the reactor below 50°C and continue the reaction for 5 hours, keeping the pH between 6.0 and 9.0. After precipitating and filtering the prepared acrylate aqueous solution, add it to a high-speed dispersion vessel at a speed of 1000–1200 rpm. Then, add 2.9 parts of N'N-dimethylbisacrylamide crosslinking agent (MBA) and stir for 15–30 minutes until completely dissolved and mixed evenly to obtain a polymer aqueous solution. Take 100 parts of the polymer aqueous solution prepared in this comparative example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0085] Example 4:

[0086] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 7 parts of light magnesium oxide and 4.7 parts of zinc oxide to the reactor, and thoroughly mix the powder with deionized water to form a suspension. Then, titrate 33 parts of acrylic acid into the reactor. Control the temperature inside the reactor to be below 50℃ and continue the reaction for 5 hours, controlling the pH to be within the range of 6.0 to 9.0. After precipitation and filtration, the above-prepared acrylate aqueous solution is added to a high-speed dispersion vessel, with the speed controlled at 1000 to 1200 rpm. Then, add 4.3 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent, and stir for 15 to 30 minutes until completely dissolved and mixed evenly to obtain a hybrid polymer aqueous solution. Take 100 parts of the hybrid polymer aqueous solution prepared in this example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0087] Comparative Example 4: Using polyethylene glycol allyl ether crosslinking agent

[0088] Add 100 parts of deionized water to the reactor and turn on the stirrer at a speed of 80 rpm. While stirring, add 7 parts of light magnesium oxide and 4.7 parts of zinc oxide to the reactor, thoroughly mixing the powders with the deionized water to form a suspension. Then, titrate 33 parts of acrylic acid into the reactor. Control the temperature inside the reactor below 50℃ and continue the reaction for 5 hours, maintaining the pH between 6.0 and 9.0. After precipitating and filtering the prepared acrylate aqueous solution, add it to a high-speed dispersion vessel at a speed of 1000–1200 rpm. Then, add 4.3 parts of polyethylene glycol allyl ether crosslinking agent and stir for 15–30 minutes until completely dissolved and mixed evenly to obtain a polymer aqueous solution. Take 100 parts of the polymer aqueous solution prepared in this comparative example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0089] Example 5:

[0090] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 5 parts of light magnesium oxide and 8 parts of zinc oxide to the reactor, and mix the powder with deionized water thoroughly to form a suspension. Then, add 31 parts of acrylic acid titrated into the reactor. Control the temperature inside the reactor to be below 50°C and continue the reaction for 5 hours, controlling the pH to be within the range of 6.0 to 9.0. After precipitating and filtering the above-prepared acrylate aqueous solution, add it to a high-speed dispersion vessel, controlling the rotation speed at 1000 to 1200 rpm. Then add 5.8 parts of the synthesized pentaerythritol tetrakis(3,4-diacryloyloxybenzoic acid) crosslinking agent, and stir for 15 to 30 minutes until completely dissolved and mixed evenly to obtain a hybrid polymer aqueous solution. Take 100 parts of the hybrid polymer aqueous solution prepared in this example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0091] Comparative Example 5: Using pentaerythritol diacrylate crosslinking agent

[0092] Add 100 parts of deionized water to the reactor and turn on the stirrer, controlling the stirring speed at 80 rpm. Under stirring conditions, add 5 parts of light magnesium oxide and 8 parts of zinc oxide to the reactor, and mix the powder with deionized water thoroughly to form a suspension. Then, add 31 parts of acrylic acid titrated into the reactor. Control the temperature inside the reactor to be below 50℃ and continue the reaction for 5 hours, maintaining the pH in the range of 6.0–9.0. After precipitating and filtering the above-prepared acrylate aqueous solution, add it to a high-speed dispersion vessel, controlling the rotation speed at 1000–1200 rpm. Then, add 5.8 parts of pentaerythritol diacrylate crosslinking agent and stir for 15–30 minutes until completely dissolved and mixed evenly to obtain a polymer aqueous solution. Take 100 parts of the polymer aqueous solution prepared in this comparative example, weigh 1 part of triethanolamine and 1 part of sodium persulfate, and prepare samples according to the performance testing methods for relevant performance tests.

[0093] Performance testing:

[0094] 1. Compressive strength of the solidified sand: Referring to the method described in section 7.9 of the industry standard JC / T 2037-2010 "Acrylic Grouting Materials", the polymer aqueous solution, triethanolamine, and sodium persulfate were rapidly mixed in the specified mass ratio and poured into a cylindrical mold with a diameter of 40mm × 100mm, which was already filled with 100mm high ISO standard sand. The mixture was allowed to cure within 30 minutes under standard conditions. After covering the surface with plastic wrap and curing for 24 hours, the compressive strength of the solidified sand was tested.

[0095] 2. Thermal expansion rate: Tested according to the method specified in section 12 of GB / T 16777-2008 "Test Methods for Waterproof Coatings for Buildings".

[0096] 3. Adhesion strength: Tested according to the method specified in 7.1A of GB / T 16777-2008 "Test Methods for Waterproof Coatings for Buildings".

[0097] 4. Resistance to extrusion failure drop: Refer to the method described in section 7.10 of the industry standard JC / T 2037-2010 "Acrylic Grouting Materials".

[0098] The results of the tests for each embodiment and comparative example are shown in Table 1.

[0099] Table 1 Performance Comparison Table

[0100]

[0101] Compared to Examples 1 to 5, the main differences lie in the monomer composition and concentration, and the type and amount of crosslinking agent, resulting in significant differences in product performance. When the monomer is a mixture of magnesium acrylate and zinc acrylate, or zinc acrylate alone, and the amount of the self-made crosslinking agent reaches more than 2 parts, better performance can be obtained, especially in terms of the compressive strength and thermal expansion rate of the solidified sand. Among them, the monomer concentration of Examples 3-5 is higher than that of Examples 1-2, and its mechanical properties such as compressive strength and adhesive strength are better.

[0102] Compared with Example 1, Comparative Example 1 did not use a crosslinking agent, and its solid sand body had very low compressive strength and adhesive strength. This proves that the crosslinking agent synthesized by this technology can improve the mechanical properties of the gel and has the advantage of being used as a crosslinking agent.

[0103] The monomer concentration in Example 2 and Comparative Example 2 was 20%, which is higher than the 15% monomer concentration in Example 1 and Comparative Example 1. In this series, Example 2 used a crosslinking agent synthesized using this technology, while the crosslinking agent used in Comparative Document 2 was polyethylene glycol diacrylate, a common crosslinking agent available on the market, which is different from the crosslinking agent in Example 2 of this invention. As can be seen from the performance comparison table, all properties of Comparative Example 2 are lower than those of Example 2, indicating that when different types of crosslinking agents are added but the amount of crosslinking agent is the same, the crosslinking agent synthesized in this invention can improve the overall performance of the gel.

[0104] The monomer concentration in Example 3 and Comparative Example 3 was 28%, higher than the 20% monomer concentration in Example 2 and Comparative Example 2. In this series, Example 3 used a crosslinking agent synthesized using this technology, while the crosslinking agent used in Comparative Document 3 was N'N-dimethylbisacrylamide, a common crosslinking agent available on the market, which is different from the crosslinking agent in Example 3 of this invention. As can be seen from the performance comparison table, all properties of Comparative Example 3 are lower than those of Example 3. This indicates that when different types of crosslinking agents are added but the amount of crosslinking agent is the same, the crosslinking agent synthesized in this invention can improve the overall performance of the gel, especially the compressive strength and thermal shrinkage rate of the solidified gel, with an improvement of nearly 2 times. This shows that increasing the amount of crosslinking agent synthesized in this invention increases the number of crosslinking points and the crosslinking density, thereby improving the mechanical strength of the gel, enhancing its water-locking ability, and reducing the shrinkage rate.

[0105] The monomer concentration in Example 4 and Comparative Example 4 was 28%. However, unlike Examples 3 and Comparative Example 3, the monomer in this series was replaced with a mixture of magnesium acrylate and zinc acrylate monomers, with a mass ratio of 7:3, instead of magnesium acrylate. Compared to magnesium acrylate, zinc acrylate polymers have higher mechanical properties but relatively lower flexibility. Therefore, this series uses a mixture of the two, with a small amount of zinc acrylate monomer added, which can improve mechanical properties to a certain extent while maintaining good flexibility. The performance data table shows that Example 4 outperforms Comparative Example 4 in all aspects of performance indicators. This is due to the different selection of crosslinking agents; more functional groups can achieve denser crosslinking.

[0106] The monomer concentration in Example 5 and Comparative Example 5 was also 28%, but unlike Example 4 and Comparative Example 4, the ratio of magnesium acrylate to zinc acrylate monomers in this series was changed from 7:3 in Example 4 to 1:1. Consistent with the previous examples, the polymer of zinc acrylate itself has higher mechanical properties than magnesium acrylate. Therefore, the increased zinc acrylate content in this series of mixtures can improve mechanical properties while maintaining a certain degree of flexibility. The performance comparison table shows that Example 5 outperforms Comparative Example 5 in all aspects of performance indicators. This is due to the different selection of crosslinking agents; more functional groups can achieve denser crosslinking.

[0107] Although the invention has been described herein with reference to illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter combination within the scope of this disclosure. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A hybrid polymer gel-based leak-proof material, characterized in that, Based on parts by weight, it includes the following three components: 100 parts of hybrid polymer aqueous solution, Accelerator: Triethanolamine 0.1–10 parts Initiator: Sodium persulfate 0.1–10 parts; The hybrid polymer aqueous solution, calculated by weight, is prepared from raw materials including the following: 100 parts deionized water 1-20 parts of light magnesium oxide 0-20 parts of zinc oxide 10-50 parts acrylic acid Crosslinking agent 0.1-6 parts, The crosslinking agent contains the following components: 。 2. The hybrid polymer gel leakage control material according to claim 1, characterized in that, Based on parts by weight, it includes the following three components: 100 parts of hybrid polymer aqueous solution, Accelerator: Triethanolamine 0.1–10 parts Initiator: Sodium persulfate 0.1–10 parts; The hybrid polymer aqueous solution, calculated by weight, is prepared from raw materials including the following: 100 parts deionized water 5-10 parts of light magnesium oxide, 4-10 parts zinc oxide 30-40 parts acrylic acid Crosslinking agent 2 to 6 parts.

3. The hybrid polymer gel leakage control material according to claim 1, characterized in that, Based on parts by weight, it includes the following three components: 100 parts of hybrid polymer aqueous solution, Accelerator: 0.5–2 parts triethanolamine Sodium persulfate initiator: 0.5–2 parts; The hybrid polymer aqueous solution, calculated by weight, is prepared from raw materials including the following: 100 parts deionized water 5-10 parts of light magnesium oxide, 4-10 parts zinc oxide 30-40 parts acrylic acid Crosslinking agent 2 to 6 parts.

4. The hybrid polymer gel leakage control material according to any one of claims 1 to 3, characterized in that, The preparation method of the crosslinking agent includes the following steps: S1: Add solvent to the reaction vessel, then add pentaerythritol, 3,4-dihydroxybenzoic acid, and p-toluenesulfonic acid in sequence, with a molar ratio of 1:4.2~5.0:0.06~0.10; turn on nitrogen protection and stir to suspend the solids evenly. S2: Heat to reflux and carry out esterification reaction for 8-12 hours with stirring; collect the water produced in the reaction, and when the amount of water no longer increases, the reaction is considered complete, and intermediate M1 is obtained; S3: Cool intermediate M1 to below 40°C, then wash with sodium bicarbonate aqueous solution, wash the organic phase with deionized water, dry, and distill under reduced pressure to obtain intermediate M2. S4: Add solvent to the reactor, then add intermediate M2, triethylamine, and polymerization inhibitor p-methoxyphenol in a molar ratio of 1:9~10:0.003~0.

005. Lower the temperature of the reaction solution to 0~5℃. Under nitrogen protection, dilute acryloyl chloride with solvent to obtain a mixture in a molar ratio of acryloyl chloride to intermediate M2 of 8.8~9.0:

1. S5: Add the mixture described in S4 dropwise while stirring. During the dropwise addition, the temperature of the reaction solution is maintained at 0-5℃. After the dropwise addition is completed, perform an acrylation reaction at 0-5℃ for 1-2 hours. Then, allow the reaction solution to naturally rise to room temperature and continue stirring for at least 12 hours. S6: Filter the reaction solution, wash the filtrate with hydrochloric acid solution, then wash with sodium bicarbonate solution, and finally wash with saturated brine; dry, concentrate, and remove impurities under vacuum to obtain the crosslinking agent.

5. The hybrid polymer gel leakage control material according to claim 4, characterized in that, The solvent in step S1 is toluene, and the solvent in step S4 is anhydrous tetrahydrofuran.

6. The hybrid polymer gel leakage control material according to claim 4, characterized in that, The reflux temperature in step S2 is 115±5℃, and the droplet acceleration of the mixed liquid in step S5 is 1.0 mL / min.

7. The hybrid polymer gel leakage control material according to claim 4, characterized in that, During the washing process in step S6, the concentration of hydrochloric acid aqueous solution is 5%, the concentration of sodium bicarbonate solution is 5%, and the hydrochloric acid aqueous solution, sodium bicarbonate solution, and saturated brine are all pre-cooled to 0°C. The temperature during the drying and concentration processes must be controlled below 35°C and protected from light.

8. A method for preparing the hybrid polymer gel leakage control material according to any one of claims 1 to 7, characterized in that... Includes the following steps: S1: Add deionized water to the reactor, and add light magnesium oxide and zinc oxide into the reactor under stirring conditions; S2: Add acrylic acid dropwise into the reactor; turn on the cold water circulation system to control the temperature inside the reactor below 50℃, and continue the reaction for 4 to 6 hours to obtain an aqueous solution of acrylate, with the pH controlled in the range of 6.0 to 9.0; S3: After precipitating and filtering the acrylate aqueous solution, add it to a high-speed dispersion vessel, and control the rotation speed at 1000-1200 rpm; add the crosslinking agent, stir evenly, and obtain a hybrid polymer aqueous solution; S4: Weigh out triethanolamine as an accelerator; S5: Weigh out sodium persulfate as the initiator.

9. The method for preparing the hybrid polymer gel leakage control material according to claim 8, characterized in that... The stirring described in S3 requires stirring the acrylate aqueous solution and the crosslinking agent in a high-speed dispersion vessel at a speed of 1000-1200 rpm for 15-30 minutes.

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