Cement-based capillary crystalline waterproof material and preparation method thereof

Abstract

The invention belongs to the technical field of concrete, and particularly relates to a cement-based capillary crystalline waterproof material and a preparation method thereof. A C-S-H at sodium siliconate-KH560-PLA core-shell carrier is prepared, an active substance amino silane modified silica sol and an aluminum-zirconium composite chelating agent are loaded, a PLA ester bond is broken along with cement hydration, the core-shell carrier forms a porous channel, the active substance is slowly released, and microcracks in concrete are continuously filled; silicon hydroxyl in the amino silane modified silica sol is subjected to condensation polymerization to generate silicic acid gel, and after amino protonation, hydrogen bonds are formed on the surface of a cement matrix, so that the interface cohesiveness of the gel and the matrix is improved; zr < 4 + > and Al < 3 + > in the aluminum-zirconium composite chelating agent and-OH of the silicic acid gel form stable coordinate bonds to form organic-inorganic composite gel, and the organic-inorganic composite gel is matched with C-S-H gel generated by rapid hydration of a C-S-H precursor in the early stage, so that the structural compactness is improved in the early stage of hydration, and the early strength of the concrete is improved.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, specifically to a cement-based penetrating crystalline waterproof material and its preparation method. Background Technology

[0002] Concrete is a conventional building material. The vast majority of it is formed by mixing silicate cement, aggregates, and various admixtures with water, hydrating, gelling, crystallizing, and solidifying into a solid. The calcium hydroxide crystals generated during cement hydration form cracks, and the expansion and contraction caused by the ettringite produced during the hydration of cement and gypsum also form cracks. The existence of these self-generated cracks is the core factor causing concrete leakage and surface corrosion.

[0003] Cement-based penetrating crystalline waterproofing material is a rigid waterproofing material made with cement as the base material and added active chemical substances. These active chemical substances are mainly substances that can complex with calcium ions in concrete to form calcium ion complexes. Through the transport of calcium ion complexes, they react chemically with moisture and unhydrated cement particles in the concrete to generate more stable crystals such as calcium sulfate, calcium silicate, and calcium carbonate, which block the capillaries and microcracks inside the concrete. These needle-like crystals spread from the cement hydrate crystals, intertwining to form a complex dendritic structure that fills the microcracks inside the concrete structure, blocking the transport of moisture, thereby effectively improving the impermeability of the concrete and achieving the effects of waterproofing and enhancing the durability of the concrete.

[0004] Currently, the core function of cement-based penetrating crystalline waterproofing materials mainly relies on the reaction of active chemical substances with concrete components to generate crystalline products that seal pores and cracks. These mainly include silicate systems, carbonate systems, and carboxylic acid systems. Among them, representative substances of the carboxylic acid system include aspartic acid, citric acid, and polyacrylic acid. The carboxyl groups in these active substances can form complexes with calcium ions, migrate to cracks, and release them, promoting local crystallization and exhibiting strong directional repair capabilities. However, the complexing effect of the carboxylic acid groups reduces the concentration of calcium ions in the matrix during the initial hydration stage. This effect delays the cement hydration reaction, which is detrimental to the early strength development of cement and also has a significant retarding problem.

[0005] Furthermore, promoting green building development has become an industry consensus, with a focus on ultra-low energy consumption building construction and energy-saving and green renovation of existing public buildings. This places higher demands on the long-term durability, energy-saving adaptability, and environmental friendliness of waterproofing materials. Traditional waterproofing materials suffer from problems such as short lifespan, high repair frequency, and difficulty in meeting the energy-saving requirements of green buildings, thus hindering the achievement of green building development goals. Summary of the Invention

[0006] The purpose of this invention is to provide a cement-based penetrating crystalline waterproof material and its preparation method to solve the above-mentioned technical problems.

[0007] To achieve the above-mentioned technical objectives, the technical solution of the present invention is as follows: A cement-based penetrating crystalline waterproofing material, characterized in that, by weight, it comprises the following components: 20-30 parts of active loaded particles, 40-50 parts of ordinary silicate cement, 2-5 parts of polycarboxylate dispersant, 3-8 parts of hydroxypropyl methylcellulose, 15-20 parts of fly ash, and 35-50 parts of water. The preparation method of the active loaded particles is as follows: the air in the CSH@sodium silicate-KH560-PLA core-shell particles is removed by vacuuming, the active mixture is added to completely immerse the CSH@sodium silicate-KH560-PLA core-shell particles, the particles are stirred and adsorbed at -0.08MPa for 2 hours, the vacuum is slowly released after the adsorption is completed, the particles are dried under vacuum, cooled to room temperature, sieved, and the portion passing through the sieve is taken to obtain the active loaded particles. The active mixture is prepared by taking 50-70 parts by weight of aminosilane modified silica sol, 10-20 parts by weight of aluminum zirconium composite chelating agent and 15-30 parts by weight of deionized water, stirring and mixing, heating to 30°C, and ultrasonically dispersing to obtain the active mixture.

[0008] As a further improvement, S1, CSH precursor was dissolved in deionized water at a mass ratio of 1:3, sodium polycarboxylate was added, and after mixing evenly, 20% sodium silicate solution was added dropwise, and stirring was continued. Triethanolamine was added, and the pH of the system was adjusted to stabilize it at 8.5~9.0. KH560 was added, and the mixture was stirred at 1200 rpm for 3 hours to obtain a core-shell structure intermediate mixture. S2. Adjust the pH of the core-shell intermediate mixture to 6.5-7.0. At 55℃ and 1200rpm, slowly add the terminal acetylated PLA emulsion and 10% DBTDL solution simultaneously and continue stirring for 1h. Then reduce the stirring speed to 1000rpm and stir for 2h. Keep the temperature at 55℃ for 3h. After the reaction is complete, collect the solid precipitate by centrifugation. Wash with deionized water and anhydrous ethanol to obtain the product slurry. S3. The product slurry is dried using a spray drying device, sieved, and the undersize portion is collected to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0009] As a further improvement, the preparation method of the CSH precursor is as follows: S1. By weight, take 45-55 parts anhydrous calcium oxide, 35-55 parts silica fume, 500 parts deionized water, 1-3 parts PEG-600, and 0.3-0.5 parts sodium citrate; mix silica fume and PEG-600 evenly, stir and add to deionized water, heat to 40℃, slowly add anhydrous calcium oxide and sodium citrate, stir at 200 rpm for 20 min to obtain CSH precursor slurry; S2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. After centrifugation, washing and freeze-drying for 12h, the mixture was lightly ground in a ball mill at 200rpm for 10min, sieved, and the undersize portion was collected to obtain the CSH precursor.

[0010] As a further improvement, the preparation method of the aminosilane-modified silica sol is as follows: Silane-ethanol solution is slowly added dropwise to the silica sol under ultrasonic dispersion at 200W, 40℃, and 500rpm. After the addition is complete, the mixture is kept at 50℃ for 2 hours, cooled to 30℃, ethylene glycol is added, and stirring continues for 30 minutes. The pH is adjusted to 7-8, and then transferred to a sealed container and allowed to stand at room temperature for 24 hours to obtain the aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 3.5-4.5:1, and the amount of ethylene glycol added is 0.5-0.8 wt% of the silica sol.

[0011] As a further improvement, the preparation method of the silane-ethanol solution is as follows: KH550 and KH540 are stirred and added to anhydrous ethanol at a mass ratio of 3:1, deionized water is slowly added dropwise, and acetic acid is added simultaneously to adjust the pH to 4.5~5.0. The solution is then ultrasonically pre-hydrolyzed at 30°C for 30 min to obtain the silane-ethanol solution; wherein, the mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water is 1:3:1.5; and the amount of acetic acid added is 2.5~3% of the total mass of KH550 and KH540.

[0012] As a further improvement, the preparation method of the aluminum-zirconium composite chelating agent is as follows: S1. Take zirconium oxychloride and citric acid in a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40°C with stirring. After it is completely dissolved, add half of the citric acid and continue stirring for 15 minutes to obtain a citric acid-zirconium complex solution. S2. At 40℃, a 0.2 mol / L aluminum chloride solution was added dropwise to a citric acid-zirconium complex solution, maintaining the pH at 2.8-3.2 during the addition. After the addition was complete, the remaining citric acid was added, and the mixture was stirred at 50℃ for 1 hour to obtain an aluminum-zirconium-citric acid ternary complex solution. The mass ratio of aluminum chloride to zirconium oxychloride in the aluminum chloride solution was 3-4:1. S3. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. The solution was stirred and added dropwise to the aluminum zirconium citrate ternary complex solution at 50°C. After the addition was complete, the pH was gradually increased using 1 mol / L NaOH solution: from 3.2 to 5.0 in 0-30 min, to 5.5 in 30-60 min, and to 6.0 in 60-90 min. Then the temperature was increased to 55°C and reacted for 2 h to obtain the aluminum zirconium composite chelating agent.

[0013] As a further improvement, the total mass ratio of glycine and sodium citrate to deionized water is 0.24:1; the mass ratio of the complex ligand solution to the aluminum zirconium citrate ternary complex solution is 1:3~5.

[0014] As a further improvement, the method for preparing the terminal acetylated PLA emulsion is as follows: take a hydroxyl-terminated PLA emulsion with a solid content of 50%, disperse it by ultrasonication at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain the terminal acetylated PLA emulsion. The 10% DBTDL solution is prepared by diluting DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution. The hydroxyl-terminated PLA has a molecular weight of 5000-10000; the amount of Tween 80 added is 0.1-0.3 wt% of the hydroxyl-terminated PLA emulsion; the molar ratio of acetic anhydride to hydroxyl-terminated PLA is 2-3:1; and the amount of DBTDL added is 0.5-0.8 wt% of the hydroxyl-terminated PLA.

[0015] As a further improvement, in step S1, the amount of sodium polycarboxylate added is 1-3 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3-5; the amount of triethanolamine added is 0.1-0.3 wt% of the CSH precursor; and the amount of KH560 added is 1.0-1.5 wt% of the CSH precursor.

[0016] The present invention also provides a method for preparing a cement-based penetrating crystalline waterproof material, comprising the following steps: first, ordinary silicate cement and fly ash are mixed at 30 rpm for 10 min, then active loaded particles are added, and the mixture is continued to be mixed at 30 rpm for 15 min, then polycarboxylate dispersant and hydroxypropyl methylcellulose are added in sequence, and the mixture is continued to be mixed for 5 min, and finally water is added and stirred for 5 min to obtain the cement-based penetrating crystalline waterproof material.

[0017] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: 1. Using CSH@sodium silicate-KH560-PLA core-shell particles loaded with aminosilane-modified nano-silica sol and an aluminum-zirconium composite chelating agent, as cement hydration progresses, the pH of the system continuously increases. The ester bonds of PLA in the core-shell particles gradually break and degrade under a strongly alkaline environment, causing the inorganic siloxane shell to form porous channels, slowly releasing the active substances loaded within the pores. The released active substances react with the Ca continuously precipitated during cement hydration. 2+ Al 3+ It works fully and continuously generates a gel phase, which can permanently repair cracks generated during concrete pouring and service, and significantly improve the impermeability of cement-based materials.

[0018] 2. During cement hydration, the silanol groups (-Si-OH) in the aminosilane-modified silica sol undergo a condensation reaction to form silica gel. After the amino groups (-NH2) are protonated, they form hydrogen bonds with the cement matrix surface, improving the interfacial adhesion between the gel and the matrix. Simultaneously, the Zr in the aluminum-zirconium composite chelating agent… 4+ Al 3+ (As a multidentate coordination center) it forms a stable coordination bond with the -OH group of silica gel, realizing the cross-linking of organic chelate chains and inorganic siloxane networks, forming a dense organic-inorganic composite gel, which effectively fills the capillaries and microcracks of cement-based materials, enhancing the mechanical properties and structural stability of concrete.

[0019] 3. The CSH precursor in CSH@sodium silicate-KH560-PLA core-shell particles rapidly hydrates in the early stage of cement hydration, generating CSH gel. Together with the organic-inorganic composite gel, it fills the pores in the early stage of hydration, reduces internal defects in cement stone, and further improves the early structural density and early strength.

[0020] 4. The material of this invention can significantly improve the sealing and durability of building structures, reduce energy loss caused by leakage, and perfectly meet the stringent energy-saving performance requirements of ultra-low energy buildings; its long-term crack repair capability can extend the service life of existing public buildings, reduce the frequency and overall cost of green renovation, and provide reliable material support for the energy-saving and green renovation of existing public buildings; the material composition is environmentally friendly and utilizes industrial by-products such as fly ash, which is in line with the environmental protection orientation of green building development and helps the industry's green transformation. Attached Figure Description

[0021] Figure 1 The microstructure test results of a reference concrete specimen hydrated for 28 days after being coated with the cement-based penetrating crystalline waterproofing material obtained in Example 3; Figure 2 The microstructure test results of the reference concrete specimen after hydration for 28 days after coating with the cement-based penetrating crystalline waterproofing material obtained in Comparative Example 2 are shown. Figure 3This is a microscopic morphology diagram of the active loaded particles obtained in Example 3. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or manufacturer's conditions shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0023] Example 1: A method for preparing a cement-based penetrating crystalline waterproofing material, comprising the following steps: 1. By weight, take 45 parts anhydrous calcium oxide, 35 parts silica fume, 500 parts deionized water, 1 part polyethylene glycol (PEG-600), and 0.3 parts sodium citrate. Mix silica fume and PEG-600 evenly, add them to deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 10.5 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0024] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0025] 3. Take a 50% solids content polylactic acid (PLA) emulsion with hydroxyl groups, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a acetylated PLA emulsion with hydroxyl groups; dilute dibutyltin dilaurate (DBTDL) with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the hydroxyl-terminated PLA is 5000; the amount of Tween 80 added is 0.1 wt% of the hydroxyl-terminated PLA emulsion; the molar ratio of acetic anhydride to hydroxyl-terminated PLA is 2:1; and the amount of DBTDL added is 0.5 wt% of the hydroxyl-terminated PLA.

[0026] 4. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 8.5. Add γ-glycidoxypropyltrimethoxysilane (KH560) and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 1 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3; the amount of triethanolamine added is 0.1 wt% of the CSH precursor; and the amount of KH560 added is 1.0 wt% of the CSH precursor.

[0027] 5. Adjust the pH of the core-shell intermediate mixture to 6.5 using dilute hydrochloric acid. At 55℃ and 1200 rpm, simultaneously add the terminal acetylated PLA emulsion and 10% DBTDL solution via a dual peristaltic pump at a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then once with anhydrous ethanol to obtain the product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheat for 30 min; outlet air temperature 62℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0028] 6. γ-aminopropyltriethoxysilane (KH550) and γ-aminopropylmethyldimethoxysilane (KH540) are added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water is slowly added dropwise, and acetic acid is added simultaneously to adjust the pH to 4.5. The mixture is pre-hydrolyzed at 300W and 30℃ for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water is 1:3:1.5. The amount of acetic acid added is 2.5 wt% of the total mass of KH550 and KH540.

[0029] 7. Treat the silica sol in a 30℃ water bath for 30 min to remove air bubbles. Place the sol in a three-necked flask, turn on the reflux condenser, and ultrasonically disperse at 200W, in a 40℃ water bath at 500 rpm. Slowly add a silane-ethanol solution dropwise to the silica sol at a rate of 1 mL / min. After the addition is complete, maintain the reaction temperature at 50℃ for 2 h, cool to 30℃, add ethylene glycol, and continue stirring for 30 min. Adjust the pH to 7 using 0.1 mol / L NaOH solution, transfer to a sealed container, and let stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, obtaining an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 3.5:1; the amount of ethylene glycol added is 0.5 wt% of the silica sol.

[0030] 8. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain at 2.8. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:3.

[0031] 9. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The temperature was then raised to 55℃ and reacted for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:3.

[0032] 10. By weight, take 50 parts of aminosilane modified silica sol, 10 parts of aluminum zirconium composite chelating agent, and 15 parts of deionized water, stir evenly at 300 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0033] 11. Add CSH@sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min to ensure that the active mixture completely submerges the CSH@sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0034] 12. By weight, take 20 parts of active loaded particles, 40 parts of ordinary silicate cement, 2 parts of polycarboxylate dispersant, 3 parts of hydroxypropyl methylcellulose, 15 parts of fly ash, and 37.5 parts of water; first, mix the ordinary silicate cement and fly ash at 30 rpm for 10 min, add the active loaded particles, continue mixing at 30 rpm for 15 min, add the polycarboxylate dispersant and hydroxypropyl methylcellulose, continue mixing for 5 min, finally add water, stir and mix for 5 min to obtain cement-based penetrating crystalline waterproof material.

[0035] Example 2: A method for preparing a cement-based penetrating crystalline waterproofing material, comprising the following steps: 1. By weight, take 50 parts anhydrous calcium oxide, 45 parts silica fume, 500 parts deionized water, 2 parts PEG-600, and 0.4 parts sodium citrate. Mix silica fume and PEG-600 evenly, add them to deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 10.8 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0036] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0037] 3. Take a 50% solid content PLA emulsion with terminal hydroxyl groups, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a acetylated PLA emulsion with terminal hydroxyl groups; dilute DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the PLA with terminal hydroxyl groups is 8000; the amount of Tween 80 added is 0.2 wt% of the PLA emulsion with terminal hydroxyl groups; the molar ratio of acetic anhydride to PLA with terminal hydroxyl groups is 2.5:1; and the amount of DBTDL added is 0.7 wt% of the PLA with terminal hydroxyl groups.

[0038] 4. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 8.7. Add KH560 and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 2 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:4; the amount of triethanolamine added is 0.3 wt% of the CSH precursor; and the amount of KH560 added is 1.3 wt% of the CSH precursor.

[0039] 5. Adjust the pH of the core-shell intermediate mixture to 6.8 using dilute hydrochloric acid. Add the terminal acetylated PLA emulsion and 10% DBTDL solution simultaneously via a dual peristaltic pump at 55℃ and 1200 rpm with a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then once with anhydrous ethanol to obtain the product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheating for 30 min; outlet air temperature 64℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0040] 6. KH550 and KH540 were added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water was added dropwise, and acetic acid was added simultaneously to adjust the pH to 4.7. The mixture was pre-hydrolyzed at 300 W and 30 °C for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water was 1:3:1.5. The amount of acetic acid added was 2.8 wt% of the total mass of KH550 and KH540.

[0041] 7. Treat the silica sol in a 30℃ water bath for 30 min to remove air bubbles. Place the sol in a three-necked flask, turn on the reflux condenser, and ultrasonically disperse at 200W, in a 40℃ water bath at 500 rpm. Slowly add a silane-ethanol solution dropwise to the silica sol at a rate of 1 mL / min. After the addition is complete, maintain the reaction temperature at 50℃ for 2 h, cool to 30℃, add ethylene glycol, and continue stirring for 30 min. Adjust the pH to 8 using 0.1 mol / L NaOH solution, transfer to a sealed container, and let stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, obtaining an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 4.0:1; the amount of ethylene glycol added is 0.7 wt% of the silica sol.

[0042] 8. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain it at 3.0. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:3.5.

[0043] 9. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The reaction was then carried out at 55℃ for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:4.

[0044] 10. By weight, take 60 parts of aminosilane modified silica sol, 15 parts of aluminum zirconium composite chelating agent, and 25 parts of deionized water, stir evenly at 400 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0045] 11. Add CSH@sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min to ensure that the active mixture completely submerges the CSH@sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0046] 12. By weight, take 25 parts of active loaded particles, 45 parts of ordinary silicate cement, 3 parts of polycarboxylate dispersant, 6 parts of hydroxypropyl methylcellulose, 18 parts of fly ash, and 44 parts of water; first, mix the ordinary silicate cement and fly ash at 30 rpm for 10 min, add the active loaded particles, continue mixing at 30 rpm for 15 min, add the polycarboxylate dispersant and hydroxypropyl methylcellulose, continue mixing for 5 min, finally add water, stir and mix for 5 min to obtain cement-based penetrating crystalline waterproof material.

[0047] Example 3: A method for preparing a cement-based penetrating crystalline waterproofing material, comprising the following steps: 1. By weight, take 55 parts anhydrous calcium oxide, 55 parts silica fume, 500 parts deionized water, 3 parts PEG-600, and 0.5 parts sodium citrate. Mix the silica fume and PEG-600 evenly, add them to the deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 11.0 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0048] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0049] 3. Take a 50% solid content PLA emulsion with terminal hydroxyl groups, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a acetylated PLA emulsion with terminal groups; dilute DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the PLA with terminal hydroxyl groups is 10000; the amount of Tween 80 added is 0.3 wt% of the PLA emulsion with terminal hydroxyl groups; the molar ratio of acetic anhydride to PLA with terminal hydroxyl groups is 3:1; and the amount of DBTDL added is 0.8 wt% of the PLA with terminal hydroxyl groups.

[0050] 4. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 9.0. Add KH560 and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 3 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:5; the amount of triethanolamine added is 0.3 wt% of the CSH precursor; and the amount of KH560 added is 1.5 wt% of the CSH precursor.

[0051] 5. Adjust the pH of the core-shell intermediate mixture to 7.0 using dilute hydrochloric acid. At 55℃ and 1200 rpm, simultaneously add the terminal acetylated PLA emulsion and 10% DBTDL solution via a dual peristaltic pump at a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then once with anhydrous ethanol to obtain the product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheating for 30 min; outlet air temperature 65℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0052] 6. KH550 and KH540 were added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water was added dropwise, and acetic acid was added simultaneously to adjust the pH to 5.0. The mixture was pre-hydrolyzed at 300W and 30℃ for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water was 1:3:1.5. The amount of acetic acid added was 3 wt% of the total mass of KH550 and KH540.

[0053] 7. Treat the silica sol in a 30℃ water bath for 30 min to remove air bubbles. Place the sol in a three-necked flask, turn on the reflux condenser, and ultrasonically disperse at 200W, in a 40℃ water bath at 500 rpm. Slowly add a silane-ethanol solution dropwise to the silica sol at a rate of 1 mL / min. After the addition is complete, maintain the reaction temperature at 50℃ for 2 h, cool to 30℃, add ethylene glycol, and continue stirring for 30 min. Adjust the pH to 8 using 0.1 mol / L NaOH solution, transfer to a sealed container, and let stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, obtaining an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 4.5:1; the amount of ethylene glycol added is 0.8 wt% of the silica sol.

[0054] 8. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain it at 3.2. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:4.

[0055] 9. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The temperature was then raised to 55℃ and reacted for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:5.

[0056] 10. By weight, take 70 parts of aminosilane modified silica sol, 20 parts of aluminum zirconium composite chelating agent, and 30 parts of deionized water, stir evenly at 500 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0057] 11. Add CSH@sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min to ensure that the active mixture completely submerges the CSH@sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0058] 12. By weight, take 30 parts of active loaded particles, 50 parts of ordinary silicate cement, 5 parts of polycarboxylate dispersant, 8 parts of hydroxypropyl methylcellulose, 20 parts of fly ash, and 50 parts of water; first, mix the ordinary silicate cement and fly ash at 30 rpm for 10 min, add the active loaded particles, continue mixing at 30 rpm for 15 min, add the polycarboxylate dispersant and hydroxypropyl methylcellulose, continue mixing for 5 min, finally add water, stir and mix for 5 min to obtain cement-based penetrating crystalline waterproof material.

[0059] Comparative Example 1: A method for preparing a cement-based penetrating crystalline waterproofing material, differing from Example 1 in that the CSH@sodium silicate-KH560-PLA core-shell particles do not contain PLA. The method specifically includes the following steps: 1. By weight, take 45 parts anhydrous calcium oxide, 35 parts silica fume, 500 parts deionized water, 1 part PEG-600, and 0.3 parts sodium citrate. Mix the silica fume and PEG-600 evenly, add them to the deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 10.5 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0060] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0061] 3. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 8.5. Add KH560 and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 1 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3; the amount of triethanolamine added is 0.1 wt% of the CSH precursor; and the amount of KH560 added is 1.0 wt% of the CSH precursor.

[0062] 5. Centrifuge the core-shell intermediate mixture at 10,000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then wash once with anhydrous ethanol to obtain a product slurry; dry the product slurry using a spray dryer, setting the inlet air temperature to 115℃, preheating for 30 min; outlet air temperature to 62℃; atomization speed to 32,000 rpm; feed rate to 600 mL / h; and induced draft fan power to 0.75 kW; pass the dried particles through a 100-mesh standard sieve, collect the undersize portion, and obtain CSH@sodium silicate-KH560 core-shell particles.

[0063] 6. KH550 and KH540 were added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water was added dropwise, and acetic acid was added simultaneously to adjust the pH to 4.5. The mixture was pre-hydrolyzed at 300 W and 30 °C for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water was 1:3:1.5. The amount of acetic acid added was 2.5 wt% of the total mass of KH550 and KH540.

[0064] 7. Treat the silica sol in a 30℃ water bath for 30 min to remove air bubbles. Place the sol in a three-necked flask, turn on the reflux condenser, and ultrasonically disperse at 200W, in a 40℃ water bath at 500 rpm. Slowly add a silane-ethanol solution dropwise to the silica sol at a rate of 1 mL / min. After the addition is complete, maintain the reaction temperature at 50℃ for 2 h, cool to 30℃, add ethylene glycol, and continue stirring for 30 min. Adjust the pH to 7 using 0.1 mol / L NaOH solution, transfer to a sealed container, and let stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, obtaining an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 3.5:1; the amount of ethylene glycol added is 0.5 wt% of the silica sol.

[0065] 8. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain at 2.8. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:3.

[0066] 9. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The temperature was then raised to 55℃ and reacted for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:3.

[0067] 10. By weight, take 50 parts of aminosilane modified silica sol, 10 parts of aluminum zirconium composite chelating agent, and 15 parts of deionized water, stir evenly at 300 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0068] 11. Add CSH@sodium silicate-KH560 core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min, ensuring that the active mixture completely submerges the CSH@sodium silicate-KH560 core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0069] 12. By weight, take 20 parts of active loaded particles, 40 parts of ordinary silicate cement, 2 parts of polycarboxylate dispersant, 3 parts of hydroxypropyl methylcellulose, 15 parts of fly ash, and 37.5 parts of water; first, mix the ordinary silicate cement and fly ash at 30 rpm for 10 min, add the active loaded particles, continue mixing at 30 rpm for 15 min, add the polycarboxylate dispersant and hydroxypropyl methylcellulose, continue mixing for 5 min, finally add water, stir and mix for 5 min to obtain cement-based penetrating crystalline waterproof material.

[0070] Comparative Example 2 describes a method for preparing a cement-based penetrating crystalline waterproofing material, which differs from Example 1 in that it does not contain aminosilane-modified silica sol. The method specifically includes the following steps: 1. By weight, take 45 parts anhydrous calcium oxide, 35 parts silica fume, 500 parts deionized water, 1 part PEG-600, and 0.3 parts sodium citrate. Mix the silica fume and PEG-600 evenly, add them to the deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 10.5 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0071] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0072] 3. Take a 50% solid content PLA emulsion with terminal hydroxyl groups, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a acetylated PLA emulsion with terminal hydroxyl groups; dilute DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the PLA with terminal hydroxyl groups is 5000; the amount of Tween 80 added is 0.1 wt% of the PLA emulsion with terminal hydroxyl groups; the molar ratio of acetic anhydride to PLA with terminal hydroxyl groups is 2:1; and the amount of DBTDL added is 0.5 wt% of the PLA with terminal hydroxyl groups.

[0073] 4. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 8.5. Add KH560 and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 1 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3; the amount of triethanolamine added is 0.1 wt% of the CSH precursor; and the amount of KH560 added is 1.0 wt% of the CSH precursor.

[0074] 5. Adjust the pH of the core-shell intermediate mixture to 6.5 using dilute hydrochloric acid. At 55℃ and 1200 rpm, simultaneously add the terminal acetylated PLA emulsion and 10% DBTDL solution via a dual peristaltic pump at a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then once with anhydrous ethanol to obtain the product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheat for 30 min; outlet air temperature 62℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0075] 6. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain at 2.8. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:3.

[0076] 7. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The reaction was then carried out at 55℃ for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:3.

[0077] 8. By weight, take 10 parts of aluminum-zirconium composite chelating agent and 15 parts of deionized water, stir evenly at 300 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0078] 9. Add CSH@sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min, ensuring that the active mixture completely submerges the CSH@sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0079] 10. By weight, take 20 parts of active loaded particles, 40 parts of ordinary silicate cement, 2 parts of polycarboxylate dispersant, 3 parts of hydroxypropyl methylcellulose, 15 parts of fly ash, and 37.5 parts of water. First, mix the ordinary silicate cement and fly ash at 30 rpm for 10 minutes. Then, add the active loaded particles and continue mixing at 30 rpm for 15 minutes. Next, add the polycarboxylate dispersant and hydroxypropyl methylcellulose and continue mixing for 5 minutes. Finally, add the water and stir for 5 minutes to obtain the cement-based penetrating crystalline waterproof material.

[0080] Comparative Example 3: A method for preparing a cement-based penetrating crystalline waterproofing material, which differs from Example 1 in that it does not include an aluminum-zirconium composite chelating agent, and specifically includes the following steps: 1. By weight, take 45 parts anhydrous calcium oxide, 35 parts silica fume, 500 parts deionized water, 1 part PEG-600, and 0.3 parts sodium citrate. Mix the silica fume and PEG-600 evenly, add them to the deionized water at 500 rpm, heat to 40℃, slowly add anhydrous calcium oxide at a rate of 1 g / min, then add sodium citrate, adjust the pH to 10.5 with 1 mol / L NaOH solution, stir and disperse at 200 rpm for 20 min to obtain CSH precursor slurry.

[0081] 2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. The product was transferred to a centrifuge tube and centrifuged at 8000rpm for 15min to separate the solid product. The product was washed three times with deionized water, freeze-dried at -50℃ and -0.09MPa for 12h, and finally lightly ground at 200rpm for 10min in a ball mill. The product was then passed through a 200-mesh sieve, and the portion passing through the sieve was collected to obtain the CSH precursor.

[0082] 3. Take a 50% solid content PLA emulsion with terminal hydroxyl groups, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a acetylated PLA emulsion with terminal hydroxyl groups; dilute DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the PLA with terminal hydroxyl groups is 5000; the amount of Tween 80 added is 0.1 wt% of the PLA emulsion with terminal hydroxyl groups; the molar ratio of acetic anhydride to PLA with terminal hydroxyl groups is 2:1; and the amount of DBTDL added is 0.5 wt% of the PLA with terminal hydroxyl groups.

[0083] 4. Add the CSH precursor to deionized water at a mass ratio of 1:3. Stir at 500 rpm for 10 min, then add sodium polycarboxylate and disperse at 40℃ and 1200 rpm for 45 min. Add 20% sodium silicate solution dropwise at a rate of 5 mL / min. After the addition is complete, continue stirring for 10 min. Add triethanolamine and stir for 5 min. Insert an online pH meter for real-time monitoring. Slowly add 0.1 mol / L dilute hydrochloric acid at a rate of 0.5 mL / min to stabilize the pH of the system at 8.5. Add KH560 and stir at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of sodium polycarboxylate added is 1 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3; the amount of triethanolamine added is 0.1 wt% of the CSH precursor; and the amount of KH560 added is 1.0 wt% of the CSH precursor.

[0084] 5. Adjust the pH of the core-shell intermediate mixture to 6.5 using dilute hydrochloric acid. At 55℃ and 1200 rpm, simultaneously add the terminal acetylated PLA emulsion and 10% DBTDL solution via a dual peristaltic pump at a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, and then once with anhydrous ethanol to obtain the product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheat for 30 min; outlet air temperature 62℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

[0085] 6. KH550 and KH540 were added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water was added dropwise, and acetic acid was added simultaneously to adjust the pH to 4.5. The mixture was pre-hydrolyzed at 300W and 30℃ for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water was 1:3:1.5. The amount of acetic acid added was 2.5 wt% of the total mass of KH550 and KH540.

[0086] 7. Treat the silica sol in a 30℃ water bath for 30 min to remove air bubbles. Place the sol in a three-necked flask, turn on the reflux condenser, and ultrasonically disperse at 200W, in a 40℃ water bath at 500 rpm. Slowly add a silane-ethanol solution dropwise to the silica sol at a rate of 1 mL / min. After the addition is complete, maintain the reaction temperature at 50℃ for 2 h, cool to 30℃, add ethylene glycol, and continue stirring for 30 min. Adjust the pH to 7 using 0.1 mol / L NaOH solution, transfer to a sealed container, and let stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, obtaining an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 3.5:1; the amount of ethylene glycol added is 0.5 wt% of the silica sol.

[0087] 8. Take 50 parts by weight of aminosilane modified silica sol and 15 parts by weight of deionized water, stir evenly at 300 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0088] 9. Add CSH@sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08MPa, maintain for 30min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50mL / min, ensuring that the active mixture completely submerges the CSH@sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200rpm for 2h, using negative pressure to allow the active material to penetrate into the pores. After adsorption, slowly release the vacuum at a decompression rate of 0.22MPa / min, and dry at 60℃ and 0.06MPa for 4h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0089] 10. By weight, take 20 parts of active loaded particles, 40 parts of ordinary silicate cement, 2 parts of polycarboxylate dispersant, 3 parts of hydroxypropyl methylcellulose, 15 parts of fly ash, and 37.5 parts of water. First, mix the ordinary silicate cement and fly ash at 30 rpm for 10 minutes. Then, add the active loaded particles and continue mixing at 30 rpm for 15 minutes. Next, add the polycarboxylate dispersant and hydroxypropyl methylcellulose and continue mixing for 5 minutes. Finally, add the water and stir for 5 minutes to obtain the cement-based penetrating crystalline waterproof material.

[0090] Comparative Example 4: A method for preparing a cement-based penetrating crystalline waterproofing material, differing from Example 1 in that the CSH@sodium silicate-KH560-PLA core-shell particles do not contain a CSH precursor. The method specifically includes the following steps: 1. Take a 50% hydroxyl-terminated PLA emulsion, ultrasonically disperse it at 20 kHz and 100 W for 15 min, add Tween 80, stir at 500 rpm for 5 min, add acetic anhydride, and continue stirring for 10 min to obtain a hydroxyl-terminated acetylated PLA emulsion; dilute DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution; wherein, the molecular weight of the hydroxyl-terminated PLA is 5000; the amount of Tween 80 added is 0.1 wt% of the hydroxyl-terminated PLA emulsion; the molar ratio of acetic anhydride to hydroxyl-terminated PLA is 2:1; and the amount of DBTDL added is 0.5 wt% of the hydroxyl-terminated PLA.

[0091] 2. Triethanolamine was added to a 20% sodium silicate solution and stirred for 5 min. An online pH meter was inserted for real-time monitoring. 0.1 mol / L dilute hydrochloric acid was slowly added dropwise at a rate of 0.5 mL / min to stabilize the pH of the system at 8.5. KH560 was added, and the mixture was stirred at 1200 rpm for 3 h to obtain a core-shell structure intermediate mixture. The amount of triethanolamine added was 0.1 wt% of the CSH precursor, and the amount of KH560 added was 1.0 wt% of the sodium silicate in the 20% sodium silicate solution.

[0092] 3. Adjust the pH of the core-shell intermediate mixture to 6.5 using dilute hydrochloric acid. At 55℃ and 1200 rpm, simultaneously add the terminal acetylated PLA emulsion and 10% DBTDL solution via a dual peristaltic pump at a dropping rate of 1 mL / min. Stir at 1200 rpm for 1 h, then reduce to 1000 rpm and stir for 2 h. Maintain the temperature at 55℃ for 3 h. After the reaction is complete, centrifuge at 10000 rpm for 15 min, collect the solid precipitate, wash twice with deionized water, then once with anhydrous ethanol. Finally, adjust the pH of the product to 6.5 to obtain a product slurry. Dry the product slurry using a spray dryer with the following settings: inlet air temperature 115℃, preheat for 30 min; outlet air temperature 62℃; atomization speed 32000 rpm; feed rate 600 mL / h; induced draft fan power 0.75 kW. Pass the dried particles through a 100-mesh standard sieve and collect the undersize portion to obtain sodium silicate-KH560-PLA core-shell particles.

[0093] 4. KH550 and KH540 are added to anhydrous ethanol at a mass ratio of 3:1 and stirred at 300 rpm. Deionized water is added dropwise while acetic acid is added to adjust the pH to 4.5. The mixture is pre-hydrolyzed at 300W and 30℃ for 30 min to obtain a silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass of anhydrous ethanol and deionized water is 1:3:1.5. The amount of acetic acid added is 2.5 wt% of the total mass of KH550 and KH540.

[0094] 5. The silica sol was kept at a constant temperature of 30℃ for 30 min to remove air bubbles. It was then placed in a three-necked flask, and reflux was started. The mixture was ultrasonically dispersed at 200W, in a 40℃ water bath at 500 rpm. A silane-ethanol solution was slowly added dropwise to the silica sol at a rate of 1 mL / min. After the addition was complete, the mixture was kept at 50℃ for 2 h. The temperature was then lowered to 30℃, ethylene glycol was added, and stirring continued for 30 min. The pH was adjusted to 7 using 0.1 mol / L NaOH solution. The mixture was transferred to a sealed container and allowed to stand at room temperature for 24 h to remove residual foam and unreacted trace amounts of silane, yielding an aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution was 3.5:1, and the amount of ethylene glycol added was 0.5 wt% of the silica sol.

[0095] 6. Take zirconium oxychloride and citric acid at a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40℃ and 300rpm with stirring. After complete dissolution, add half of the citric acid and continue stirring for 15min to obtain a citric acid-zirconium complex solution; at 40℃, add 0.2mol / L aluminum chloride solution dropwise to the citric acid-zirconium complex solution. During the dropwise addition, use 1mol / L hydrochloric acid to adjust the pH to maintain at 2.8. After the dropwise addition is complete, add the remaining citric acid and stir the reaction at 50℃ for 1h to obtain an aluminum-zirconium-citric acid ternary complex solution; wherein, the mass ratio of aluminum chloride in the zirconium oxychloride to aluminum chloride solution is 1:3.

[0096] 7. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. This solution was added dropwise to the aluminum-zirconium-citric acid ternary complex solution at a rate of 1 mL / min at 50℃ and 500 rpm. After the addition was complete, the pH was gradually increased using a 1 mol / L NaOH solution: from 3.2 to 5.0 within 0–30 min, to 5.5 within 30–60 min, and to 6.0 within 60–90 min. The reaction was then carried out at 55℃ for 2 h to obtain the aluminum-zirconium composite chelating agent. The mass ratio of the total mass of glycine and sodium citrate to deionized water was 0.24:1; the mass ratio of the composite ligand solution to the aluminum-zirconium-citric acid ternary complex solution was 1:3.

[0097] 8. By weight, take 50 parts of aminosilane modified silica sol, 10 parts of aluminum zirconium composite chelating agent, and 15 parts of deionized water, stir evenly at 300 rpm, heat to 30℃, and ultrasonically disperse at 300W and 40kHz for 30 minutes to ensure that the mixture does not agglomerate, and obtain an active mixture.

[0098] 9. Add sodium silicate-KH560-PLA core-shell particles to a vacuum stirred tank, evacuate to -0.08 MPa, maintain for 30 min, and remove air from the pores inside the particles; add the active mixture at an injection rate of 50 mL / min to ensure that the active mixture completely submerges the sodium silicate-KH560-PLA core-shell particles, and perform negative pressure adsorption at 200 rpm for 2 h to allow the active substance to penetrate into the pores using negative pressure. After adsorption, slowly release the vacuum at a depressurization rate of 0.22 MPa / min, and dry at 60℃ and 0.06 MPa for 4 h to remove free moisture. After cooling to room temperature, pass through a 120-mesh sieve and take the portion that passes through the sieve to obtain the active loaded particles.

[0099] 10. By weight, take 20 parts of active loaded particles, 40 parts of ordinary silicate cement, 2 parts of polycarboxylate dispersant, 3 parts of hydroxypropyl methylcellulose, 15 parts of fly ash, and 37.5 parts of water. First, mix the ordinary silicate cement and fly ash at 30 rpm for 10 minutes. Then, add the active loaded particles and continue mixing at 30 rpm for 15 minutes. Next, add the polycarboxylate dispersant and hydroxypropyl methylcellulose and continue mixing for 5 minutes. Finally, add the water and stir for 5 minutes to obtain the cement-based penetrating crystalline waterproof material.

[0100] The cement-based penetrating crystalline waterproofing materials obtained in each embodiment and comparative example were tested in accordance with GB18445-2012.

[0101] 1. The pore structure of the reference concrete specimens coated with cement-based penetrating crystalline waterproofing material was characterized by mercury intrusion porosimetry. The test results are shown in Table 1.

[0102] Table 1. Pore structure test results of reference concrete at different curing ages.

[0103] As shown in Table 1, the reference concrete specimens coated with cement-based penetrating crystalline waterproofing materials obtained in Examples 1-3 had a slightly higher porosity than Comparative Example 1 at 7 days, but a lower porosity at all other ages. In Comparative Example 1, due to the lack of PLA in the core-shell particles, the active substances loaded with the cement-based penetrating crystalline waterproofing material are immediately released after being added to the concrete. These substances combine with calcium and aluminum ions in the system to form a cementitious substance, filling the capillaries and microcracks in the concrete cementitious system and reducing early porosity. As hydration progresses, the active substances are rapidly consumed, preventing continuous gel formation. Therefore, the porosity in the later stages of hydration is higher than in other examples and comparative examples. Comparative Examples 2 and 3 lack aminosilane-modified silica sol and aluminum-zirconium composite chelating agents, respectively, resulting in lower cementitious content in the concrete system compared to the examples. Consequently, their porosity is slightly higher than in Examples 1-3. In Comparative Example 4, the core-shell particles lack CSH precursors, preventing rapid hydration and the formation of a gel composite with the active substances in the loaded particles. This fills the pores in the early stages of hydration. Therefore, the porosity of the reference concrete obtained in Comparative Example 4 is higher than in other examples and comparative examples in the early stages of hydration. 2. Compressive and flexural strength The compressive and flexural strength of the reference concrete specimens coated with cement-based penetrating crystalline waterproofing material at different hydration ages were tested, and the test results are shown in Table 2.

[0104] Table 2 Compressive and flexural strengths of reference concrete at different curing ages

[0105] Table 2 shows that the reference concrete specimens coated with the cement-based penetrating crystalline waterproofing materials obtained in Examples 1-3, except for a slightly lower strength at 7 days compared to Comparative Example 1, had higher strengths at all other ages. This result corresponds to the pore structure test results. The CSH@sodium silicate-KH560 core-shell particles in Comparative Example 1 lacked PLA components. After being added to the reference concrete system, the active substances in the core-shell particles were directly released, reacting with the Ca in the system. 2+ Al 3+ Contact gel formation contributes to the early strength of concrete, but the continuous formation of gel cannot be achieved, resulting in insufficient later strength development. Comparative Examples 2 and 3 lack aminosilane-modified silica sol and aluminum-zirconium composite chelating agent, respectively. The resulting concrete system lacks the organic chelate chain-inorganic siloxane composite gel possessed in Examples 1-3, thus the strength is slightly lower than that of the examples. The sodium silicate-KH560-PLA core-shell particles in Comparative Example 4 lack CSH precursor, which cannot provide early strength for the reference concrete specimen. Therefore, the 7-day strength is much lower than that of other examples and comparative examples.

[0106] 3. Microstructure Microstructure tests were conducted on reference concrete specimens hydrated for 28 days after coating with the cement-based penetrating crystalline waterproofing materials obtained in Example 3 and Comparative Example 2. The test results are as follows: Figure 1 and Figure 2 As shown.

[0107] Depend on Figure 1 (a) and Figure 2 (a) It can be seen that the reference concrete specimen coated with the cement-based penetrating crystalline waterproofing material obtained in Example 3 has a denser surface structure and fewer surface pores. In contrast, the reference concrete specimen coated with the cement-based penetrating crystalline waterproofing material obtained in Comparative Example 2 has more obvious pores and cracks in its morphology. Compared with the reference concrete specimen coated with the cement-based penetrating crystalline waterproofing material obtained in Example 3, the surface structure is not smooth enough.

[0108] Depend on Figure 1 (b) and Figure 2 (b) It can be seen that the reference concrete specimen coated with the cement-based penetrating crystalline waterproofing material obtained in Example 3 has more needle-like crystals and gel substances generated inside the structure, which are evenly distributed inside the concrete, tightly arranged, and have fewer pores, which is conducive to enhancing the mechanical properties of the concrete. In the reference concrete specimen coated with the cement-based penetrating crystalline waterproofing material obtained in Comparative Example 2, a certain amount of needle-like ettringite and calcium hydroxide are also generated. However, due to the lack of aminosilane-modified silica sol, the gel substances in the structure are significantly reduced and cannot be bonded to other hydration products, resulting in a decrease in strength.

[0109] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A cement-based penetrating crystalline waterproofing material, characterized in that, By weight, it includes the following components: 20-30 parts of active loaded particles, 40-50 parts of ordinary silicate cement, 2-5 parts of polycarboxylate dispersant, 3-8 parts of hydroxypropyl methylcellulose, 15-20 parts of fly ash, and 35-50 parts of water. The preparation method of the active loaded particles is as follows: the air in the CSH@sodium silicate-KH560-PLA core-shell particles is removed by vacuuming, the active mixture is added to completely immerse the CSH@sodium silicate-KH560-PLA core-shell particles, the particles are stirred and adsorbed at -0.08MPa for 2 hours, the vacuum is slowly released after the adsorption is completed, the particles are dried under vacuum, cooled to room temperature, sieved, and the portion passing through the sieve is taken to obtain the active loaded particles. The active mixture is prepared by taking 50-70 parts by weight of aminosilane modified silica sol, 10-20 parts by weight of aluminum zirconium composite chelating agent and 15-30 parts by weight of deionized water, stirring and mixing, heating to 30°C, and ultrasonically dispersing to obtain the active mixture.

2. The cement-based penetrating crystalline waterproofing material according to claim 1, characterized in that, The preparation method of the CSH@sodium silicate-KH560-PLA core-shell particles is as follows: S1. Dissolve the CSH precursor in deionized water at a mass ratio of 1:3, add sodium polycarboxylate, mix well, add 20% sodium silicate solution dropwise, continue stirring and mixing, add triethanolamine, adjust the pH of the system to stabilize it at 8.5~9.0, add KH560, stir at 1200rpm for 3h to obtain a core-shell structure intermediate mixture. S2. Adjust the pH of the core-shell intermediate mixture to 6.5-7.

0. At 55℃ and 1200rpm, slowly add the terminal acetylated PLA emulsion and 10% DBTDL solution simultaneously and continue stirring for 1h. Then reduce the stirring speed to 1000rpm and stir for 2h. Keep the temperature at 55℃ for 3h. After the reaction is complete, collect the solid precipitate by centrifugation. Wash with deionized water and anhydrous ethanol to obtain the product slurry. S3. The product slurry is dried using a spray drying device, sieved, and the undersize portion is collected to obtain CSH@sodium silicate-KH560-PLA core-shell particles.

3. The cement-based penetrating crystalline waterproofing material according to claim 2, characterized in that, The preparation method of the CSH precursor is as follows: S1. By weight, take 45-55 parts anhydrous calcium oxide, 35-55 parts silica fume, 500 parts deionized water, 1-3 parts PEG-600, and 0.3-0.5 parts sodium citrate; mix silica fume and PEG-600 evenly, stir and add to deionized water, heat to 40℃, slowly add anhydrous calcium oxide and sodium citrate, stir at 200 rpm for 20 min to obtain CSH precursor slurry; S2. The CSH precursor slurry was heated to 120℃ at a heating rate of 5℃ / min and reacted at 0.2MPa and 300rpm for 2h. After the reaction was completed, the temperature was lowered to 25℃ at a cooling rate of 10℃ / min to terminate the reaction. After centrifugation, washing and freeze-drying for 12h, the mixture was lightly ground in a ball mill at 200rpm for 10min, sieved, and the undersize portion was collected to obtain the CSH precursor.

4. The cement-based penetrating crystalline waterproofing material according to claim 1, characterized in that, The preparation method of the aminosilane-modified silica sol is as follows: Silane-ethanol solution is slowly added dropwise to the silica sol under ultrasonic dispersion at 200W, 40℃, and 500rpm. After the addition is complete, the mixture is kept at 50℃ for 2 hours, cooled to 30℃, ethylene glycol is added, and stirring continues for 30 minutes. The pH is adjusted to 7-8, and then transferred to a sealed container and allowed to stand at room temperature for 24 hours to obtain the aminosilane-modified silica sol. The mass ratio of the silica sol to the silane-ethanol solution is 3.5-4.5:1, and the amount of ethylene glycol added is 0.5-0.8 wt% of the silica sol.

5. The cement-based penetrating crystalline waterproofing material according to claim 4, characterized in that, The silane-ethanol solution is prepared as follows: KH550 and KH540 are stirred and added to anhydrous ethanol at a mass ratio of 3:1, deionized water is slowly added dropwise, and acetic acid is added simultaneously to adjust the pH to 4.5-5.

0. The solution is then ultrasonically pre-hydrolyzed at 30°C for 30 minutes to obtain the silane-ethanol solution. The mass ratio of the total mass of KH550 and KH540 to the mass ratio of anhydrous ethanol and deionized water is 1:3:1.

5. The amount of acetic acid added is 2.5-3% of the total mass of KH550 and KH540.

6. The cement-based penetrating crystalline waterproofing material according to claim 1, characterized in that, The preparation method of the aluminum-zirconium composite chelating agent is as follows: S1. Take zirconium oxychloride and citric acid in a mass ratio of 1:2; add zirconium oxychloride to deionized water at 40°C with stirring. After it is completely dissolved, add half of the citric acid and continue stirring for 15 minutes to obtain a citric acid-zirconium complex solution. S2. At 40℃, a 0.2 mol / L aluminum chloride solution was added dropwise to a citric acid-zirconium complex solution, maintaining the pH at 2.8-3.2 during the addition. After the addition was complete, the remaining citric acid was added, and the mixture was stirred at 50℃ for 1 hour to obtain an aluminum-zirconium-citric acid ternary complex solution. The mass ratio of aluminum chloride to zirconium oxychloride in the aluminum chloride solution was 3-4:

1. S3. Glycine and sodium citrate were dissolved in deionized water at a mass ratio of 2:1 to obtain a composite ligand solution. The solution was stirred and added dropwise to the aluminum zirconium citrate ternary complex solution at 50°C. After the addition was complete, the pH was gradually increased using 1 mol / L NaOH solution: from 3.2 to 5.0 in 0-30 min, to 5.5 in 30-60 min, and to 6.0 in 60-90 min. Then the temperature was increased to 55°C and reacted for 2 h to obtain the aluminum zirconium composite chelating agent.

7. The cement-based penetrating crystalline waterproofing material according to claim 6, characterized in that, The total mass ratio of glycine and sodium citrate to deionized water is 0.24:1; the mass ratio of the complex ligand solution to the aluminum zirconium citrate ternary complex solution is 1:3~5.

8. The cement-based penetrating crystalline waterproofing material according to claim 2, characterized in that, The method for preparing the terminal acetylated PLA emulsion is as follows: Take a 50% solid content terminal hydroxyl PLA emulsion, disperse it by ultrasonication at 20kHz and 100W for 15min, add Tween 80, stir at 500rpm for 5min, add acetic anhydride, and continue stirring for 10min to obtain the terminal acetylated PLA emulsion. The 10% DBTDL solution is prepared by diluting DBTDL with anhydrous ethanol to obtain a 10% DBTDL solution. The hydroxyl-terminated PLA has a molecular weight of 5000-10000; the amount of Tween 80 added is 0.1-0.3 wt% of the hydroxyl-terminated PLA emulsion; the molar ratio of acetic anhydride to hydroxyl-terminated PLA is 2-3:1; and the amount of DBTDL added is 0.5-0.8 wt% of the hydroxyl-terminated PLA.

9. A cement-based penetrating crystalline waterproofing material according to claim 2, characterized in that, In step S1, the amount of sodium polycarboxylate added is 1-3 wt% of the CSH precursor; the mass ratio of the 20% sodium silicate solution to the CSH precursor is 1:3-5; the amount of triethanolamine added is 0.1-0.3 wt% of the CSH precursor; and the amount of KH560 added is 1.0-1.5 wt% of the CSH precursor.

10. A method for preparing a cement-based penetrating crystalline waterproof material according to any one of claims 1-9, characterized in that, The process includes the following steps: First, mix ordinary silicate cement and fly ash at 30 rpm for 10 minutes, add active loaded particles, continue mixing at 30 rpm for 15 minutes, then add polycarboxylate dispersant and hydroxypropyl methylcellulose in sequence, continue mixing for 5 minutes, and finally add water and stir for 5 minutes to obtain cement-based penetrating crystalline waterproof material.

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