Waterproof material, method for preparing the same and use thereof

Abstract

The application relates to the field of building waterproof materials, and discloses a waterproof material and a preparation method and application thereof. The waterproof material contains composite cementing, composite filler, active permeation component, compound additive and microcapsule self-healing agent; the composite cementing contains ordinary Portland cement, sulphoaluminate cement and high belite cement; the mass ratio of the ordinary Portland cement, the sulphoaluminate cement and the high belite cement is 4-10:2-6:1; wherein, the total mass of the composite cementing is 100 parts, the amount of the composite filler is 44-77 parts, the amount of the active permeation component is 5-12.5 parts, the amount of the compound additive is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts. The waterproof material has the advantages of large permeation depth, wide repairable cracks, excellent mechanical properties, environmental protection and economy.

Description

Technical Field

[0001] This invention relates to the field of building waterproofing materials, specifically to a waterproofing material, its preparation method, and its application. Background Technology

[0002] Cement-based penetrating crystalline waterproofing materials are core materials for underground, hydraulic engineering, and kitchen and bathroom waterproofing. They are mainly divided into three categories: penetrating crystalline type, polymer cement type, and quick-setting leak-stopping type. Penetrating crystalline materials rely on the secondary hydration of active components and cement hydration products to generate insoluble silicate crystals that seal capillaries and microcracks, providing long-lasting waterproofing and self-healing advantages, and have a wide range of applications.

[0003] Existing cement-based penetrating crystalline waterproofing materials suffer from several technical bottlenecks: First, the cementitious system is mostly composed of ordinary silicate cement, making it difficult to coordinate hydration rate, expansion performance, and strength development, which easily leads to early cracking and later strength reduction. Second, the active components are prone to agglomeration and poor dispersibility, resulting in an effective penetration depth of less than 10mm. They can only repair microcracks smaller than 0.3mm, and have no self-healing ability for wide cracks, leading to a high risk of waterproofing failure. Third, the formulation and additives are single-component compounded, making it difficult to balance construction fluidity and waterproofing durability. Rapid setting modification results in insufficient toughness, while slow setting modification reduces impermeability. Fourth, some products contain heavy metals and easily release volatile VOCs, resulting in poor environmental performance. Furthermore, the filler relies on natural quartz sand, leading to high resource consumption and high costs.

[0004] Existing related patents, such as CN115286789A and CN114854027A, mostly employ single-component replacement or minor ratio adjustments. CN115286789A uses only a single cementitious system, lacking vacuum activation and wide crack self-healing design; CN114854027A does not involve ternary cementitious compounding, resulting in limited performance improvement. It fails to achieve synergistic innovation in the cementitious system, active components, and preparation process, leading to a small overall performance improvement and difficulty in adapting the process to industrial mass production. This fails to meet the high-standard engineering requirements for long-term seepage prevention, crack resistance, self-healing, and environmental friendliness. Therefore, developing cement-based waterproofing materials that combine deep penetration, high-efficiency self-healing, excellent mechanical properties, and environmental cost reduction has become a pressing technical challenge for the industry. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of early cracking, shallow penetration depth, inability to self-heal wide cracks, and long-term mechanical property degradation in existing cement-based waterproof materials with a single cementitious system. This invention provides a waterproof material, its preparation method, and its application. This waterproof material has the advantages of large penetration depth, ability to repair wide cracks, excellent mechanical properties, and environmental friendliness and economy.

[0006] To achieve the above objectives, the present invention provides a waterproof material comprising composite gelling agent, composite filler, active penetrating component, compound additives and microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

[0007] A second aspect of the present invention provides a method for preparing a waterproof material, the method comprising: mixing and reacting composite cementitious material, composite filler, active penetrating component, compounded additive and microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

[0008] A third aspect of the present invention provides the application of the waterproof material as described above or the waterproof material prepared by the preparation method as described above in concrete waterproofing or crack self-repair.

[0009] Through the above technical solution, this invention, by limiting the dosage ratio of composite cementitious material, composite filler, active penetrating component, compound additives, and microcapsule self-healing agent, enables ordinary silicate cement, sulfoaluminate cement, and high-belite cement to synergistically regulate the hydration heat release rate and volume stability, inhibiting early drying shrinkage cracking and later strength reduction. The active penetrating component ensures the deep migration of active substances into the concrete interior, and the microcapsule self-healing agent releases crystallization precursors upon rupture, enabling self-repair of wide cracks. The synergistic effect of these technical features gives the waterproof material provided by this invention deep penetration, wide crack self-healing, and long-term stable waterproof performance. Detailed Implementation

[0010] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0011] The first aspect of this invention provides a waterproof material comprising a composite gelling agent, a composite filler, an active penetrating component, a compounding agent, and a microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

[0012] The ordinary silicate cement used in this invention is P O 52.5 grade ordinary Portland cement (compliant with GB 175-2023 standard for general Portland cement) to ensure long-term strength, the sulfoaluminate cement used compensates for early shrinkage, and the high belite cement used smooths the peak of hydration heat release; the three are compounded to inhibit drying shrinkage cracking and eliminate the problem of long-term strength reduction.

[0013] This invention limits the proportions of composite cementitious material, composite filler, active penetrating component, compounding additives, and microcapsule self-healing agent. The composite cementitious material is a ternary blend of ordinary silicate cement, sulfoaluminate cement, and high-belite cement. The three types of cement have different hydration rates, effectively controlling the hydration heat release rate and volume stability, inhibiting early drying shrinkage cracking while maintaining continuous long-term compressive strength growth. The active penetrating component ensures deep migration of active substances into the concrete interior, and the microcapsule self-healing agent releases crystallization precursors upon rupture, enabling self-repair of wide cracks. The synergistic effect of these technical features gives the waterproof material provided by this invention deep penetration, wide crack self-healing, and long-term stable waterproof performance.

[0014] According to the present invention, preferably, the active penetrating component is selected from at least one of nano-silicon, magnesium fluorosilicate, and chelating calcium complexing agent. Nano-silicon provides crystallization nucleation sites, magnesium fluorosilicate accelerates silicate precipitation, and disodium EDTA continuously supplies calcium ions through complexation-slow release, extending the penetration distance of active ions. The present invention utilizes nano-silicon to fill the capillary pores of cement stone and participate in secondary hydration, magnesium fluorosilicate to promote the reaction of silicate ions with calcium ions to generate insoluble crystals, and chelating calcium complexing agent to continuously transport calcium ions to cracks through a complexation-release cycle. The inventors have found that the three components synergistically complement each other during the penetration and crystallization process, further enhancing the migration ability of the active component into the concrete, thereby significantly improving the penetration and crystallization efficiency of the waterproofing material.

[0015] In this invention, the chelating calcium complexing agent is preferably at least one of ethanolamine, hypotriacetic acid, and EDTA. Ethanolamine, hypotriacetic acid, and EDTA all possess strong complexing abilities for calcium ions and can stably exist and continuously exert their effects in the alkaline environment formed during cement hydration. The inventors have discovered that all three contain multiple coordinating atoms in their molecular structure, enabling them to form stable water-soluble complexes with calcium ions, effectively inhibiting premature precipitation of calcium ions.

[0016] Preferably, the particle size of the nano-silicon is 30-50 nm. Controlling the particle size of the nano-silicon to 30-50 nm avoids agglomeration of excessively fine particles due to high surface energy, while ensuring sufficient specific surface area for participation in the hydration reaction. Nano-silicon within this particle size range can be uniformly dispersed in the cementitious system, filling the capillary pores of cement stone and acting as nucleation sites to promote CSH gelation, making the hardened cement body more compact. Simultaneously, after dissolving in an alkaline environment, the nano-silicon releases silicate ions, which react with calcium ions to form insoluble silicate crystals, thereby improving the waterproofing material's impermeability and self-healing effect.

[0017] According to the present invention, preferably, the active penetrating component is nano-silicon, magnesium fluorosilicate, and a chelating calcium complexing agent. The inventors discovered that these three components form a continuous "penetration-complexation-crystallization" reaction chain within the same system, refining pores and increasing ion penetration distance: nano-silicon provides nucleation sites, magnesium fluorosilicate accelerates silicate ion release, and the chelating calcium complexing agent continuously supplies calcium ions, allowing the crystallization reaction to continue throughout the entire application process of the waterproof material. This further enhances the density and self-healing durability of the waterproof layer, thereby ensuring that the waterproof material maintains stable waterproof and self-healing capabilities during long-term use.

[0018] More preferably, the mass ratio of the nano-silicon, the magnesium fluorosilicate, and the chelated calcium complexing agent is 2-8:1-4:1. The inventors discovered in their research that this preferred ratio range ensures that the three active components are consumed simultaneously and react synergistically in the cement hydration system, avoiding any component being excessive or insufficient, which could interrupt the reaction chain and maximize the penetration and crystallization efficiency of the waterproofing material.

[0019] According to the present invention, preferably, the microcapsule self-healing agent consists of a core material and a wall material covering the core material. The core material is silicate crystals, and the wall material is urea-formaldehyde resin. The present invention utilizes the urea-formaldehyde resin capsule wall to form an isolation and protection for the basic silicate crystal core material, isolating it from moisture and mechanical disturbance during mixing and storage, ensuring the long-term stability of the active precursor of the core material. When cracks appear in the concrete matrix and moisture penetrates along the cracks, the mechanical stress generated by the crack expansion tears the urea-formaldehyde resin capsule wall. The internal silicate crystal core material is released with the moisture and reacts rapidly with calcium ions in the concrete system to generate insoluble silicate crystals, filling and sealing the crack channels, thereby achieving self-repairing and long-term repair of concrete cracks.

[0020] More preferably, the microcapsule self-healing agent has a particle size of 50-100 μm. The inventors unexpectedly discovered that microcapsules within this particle size range can be uniformly dispersed in the gelation system, which avoids the risk of breakage due to excessively fine particles having a large specific surface area, while ensuring that the microcapsules can fully respond to rupture and release within the cracks, thereby giving the waterproof material excellent self-repairing capabilities.

[0021] According to the present invention, preferably, the composite filler contains at least one of quartz sand, silica fume, and steel slag powder. Any one of these three fillers can independently perform a filling or activating function; selecting at least one provides basic skeletal support or micro-aggregate filling. If two or more are selected simultaneously, they can complement each other at the particle size distribution level, further reducing the internal porosity of the waterproofing material.

[0022] According to the present invention, preferably, the composite filler contains quartz sand, microsilica powder, and steel slag powder. The steel slag powder used in this invention is converter steel slag powder, which has undergone long-term aging and grinding, and its stability has been tested according to the boiling method of GB / T 1346. Microsilica powder fills the micron-sized pores between quartz sand particles, while steel slag powder not only replaces part of the natural quartz sand but also participates in the hydration reaction with its contained active silicate minerals. The inventors discovered in their research that the synergistic effect of the three fillers significantly increases the bulk density of the composite filler, fills the micropores, and thus effectively improves the density of the hardened waterproof material.

[0023] The preferred mass ratio of the silica sand, the microsilica powder, and the steel slag powder in this invention is 1.33-3:0.33-0.8:1. The inventors discovered that within this preferred ratio range, the three fillers can form a dense packing, further enhancing the waterproof material's impermeability and mechanical strength, thus making the waterproof material more stable under water pressure and load.

[0024] Preferably, the particle size of the steel slag powder is ≤74μm. The particle size of the steel slag powder is the average particle size. The steel slag powder used in this invention is uniformly dispersed in the cementitious system after being screened through a 200-mesh sieve. Its micro-aggregate filling effect and hydration activity are fully utilized, realizing the resource utilization of industrial solid waste without reducing waterproof performance. This allows the waterproof material to maintain waterproof performance while also possessing environmental protection and cost advantages.

[0025] The inventors also discovered that by further controlling the average particle size of steel slag powder within the range of 8-25μm, a balance can be struck between grinding energy consumption and activity, while avoiding the problems of increased energy consumption and water demand caused by excessively fine grinding.

[0026] More preferably, the steel slag powder has an average particle size of 10-20 μm and a specific surface area of ​​500-650 m². 2The steel slag powder contains 10-20 μm particles, which account for more than 30% of the total mass. The 10-20 μm particle size has the most significant promoting effect on the strength of steel slag cement. When the specific surface area is controlled at 500-650 m² / kg, the activity of the steel slag powder can be fully utilized. When the 10-20 μm particle size content accounts for more than 30% of the total mass, it ensures that this key particle size occupies a dominant proportion in the system. Under the above optimized conditions, the micro-aggregate filling effect and hydration activity of the steel slag powder are synergistically enhanced, further improving the hardened density and long-term strength of the waterproof material.

[0027] According to the present invention, preferably, the compounding additives are selected from at least one of polycarboxylate superplasticizer, hydroxypropyl methylcellulose ether, and PVA fiber. The superplasticizer reduces the amount of mixing water, thereby increasing the material density; the cellulose ether enhances the water retention and workability of the slurry; and the PVA fiber, selected as 2-4 mm short-cut PVA fiber, inhibits plastic shrinkage cracks at the microscopic level. The inventors have found that the three additives have complementary and synergistic effects, simultaneously addressing fluidity, water retention, and resistance to plastic cracking, further improving the hardened properties of the waterproof material.

[0028] More preferably, the compounded additives are polycarboxylate-based high-efficiency water-reducing agents, hydroxypropyl methylcellulose ether, and PVA fibers. These three additives work synergistically during the construction and curing stages: the water-reducing agent improves performance, the cellulose ether ensures sufficient moisture during the curing period, and the PVA fibers continue to provide crack resistance after curing, thus ensuring the waterproof material remains intact throughout the entire hydration and curing process.

[0029] More preferably, the mass ratio of the polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, and PVA fiber is 0.25-0.625:0.08-0.25:1. The inventors have discovered that this preferred ratio range ensures a balance between the flowability, water retention, and toughness of the compounded additives, enabling them to achieve excellent hardened body performance while meeting construction requirements, thereby optimizing the overall performance of the waterproof material.

[0030] A second aspect of the present invention provides a method for preparing a waterproof material, the method comprising: mixing and reacting composite cementitious material, composite filler, active penetrating component, compounded additive and microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

[0031] Through the above mixing reaction steps, the components are uniformly dispersed under mechanical stirring. The hydration reaction of the composite cementitious material, the ion migration of the active penetrating components, and the distribution of the microcapsule self-healing agent are synergistically optimized, resulting in a uniform and dense structure in the hardened cement body. During the mixing process, the composite cementitious material and composite filler are mixed first to form a skeleton base. The active penetrating components are uniformly attached to the surface of the cementitious particles under stirring. The compounded additives improve the rheological properties of the slurry and promote the interfacial bonding of the components. The microcapsule self-healing agent is added in the later stage of mixing to avoid mechanical damage to the capsule wall caused by prolonged stirring, ensuring that it maintains its complete burst-release response capability during the use stage. Under the above synergistic effect, the waterproof material provided by this invention has the characteristics of deep penetration, wide crack self-healing, and long-term stable waterproof performance.

[0032] Some preferred embodiments of the present invention refer to the preferred embodiments of a waterproof material provided in the first aspect of the present invention, which will not be repeated here by the applicant.

[0033] According to the present invention, preferably, the preparation method of the microcapsule self-healing agent includes: mixing the silicate crystals and the urea-formaldehyde resin, and using an in-situ polymerization method to polymerize the urea-formaldehyde resin on the surface of the silicate crystals to form a capsule wall. The in-situ polymerization method directly forms a shell on the surface of the core material, resulting in a uniform and dense capsule wall thickness, ensuring the structural integrity of the microcapsules during storage and stirring. The inventors have discovered that the microcapsule self-healing agent prepared by this method ruptures and releases the core material upon contact with water, thereby ensuring that the waterproof material possesses a stable self-healing trigger mechanism during use.

[0034] According to the present invention, preferably, the method for preparing the silicate crystals includes: mixing water glass with a modulus of 3.2-3.5 and a Baume degree of 38-40 with calcium hydroxide at a mass ratio of 2:1, and stirring at 150-250 rpm for 25-35 minutes at 10-30°C. The inventors have discovered that the water glass obtained under these preparation conditions reacts with calcium hydroxide to form highly reactive basic calcium silicate, which, upon contact with water, can rapidly react with calcium ions and silicate ions in concrete to form insoluble silicate crystals, thereby ensuring the rapid initiation and continuous stable progress of the crystallization reaction at cracks in the waterproofing material.

[0035] More preferably, the mass ratio of the silicate crystals to the urea-formaldehyde resin is 1:1.5-2.5. Within this core-to-wall ratio range, the capsule wall thickness is moderate, the wall material protects the core material from external interference, and at the same time ensures that the capsule wall can rupture in time to release the core material when cracks occur, thus further improving the self-healing response speed of the waterproof material.

[0036] According to the present invention, preferably, the conditions for the in-situ polymerization method include: adjusting the pH to 4-5, the reaction temperature to 60-70℃, and the heat preservation reaction time to 1.5-2.5h. The inventors have found in their research that these preferred conditions allow the capsule wall to solidify completely and have a smooth, defect-free surface, ensuring both capsule wall quality and production efficiency, thereby making the supply of the self-healing dosage of the waterproof material stable and controllable.

[0037] According to the present invention, preferably, the mixing reaction conditions include: a vacuum degree of -0.08 to -0.07 MPa, a temperature of 40-50°C, and a time of 2-2.5 h. The negative pressure environment can break the electrostatic adsorption and particle agglomeration of the powder, allowing the components to be fully dispersed during the mixing process; the low-temperature thermal field of 40-50°C can reduce the surface energy of the nano-active silicon, while preventing the microcapsule wall material from softening or deforming due to heat; the continuous treatment time of 2-2.5 h ensures sufficient contact between the interfaces of each component, uniform reaction, and small batch-to-batch performance fluctuations. The treatment under the above preferred embodiment can further improve the penetration depth and crack self-healing rate of the waterproof material, thereby providing dual protection for the waterproof performance and reliability of the waterproof material.

[0038] According to a particularly preferred embodiment of the present invention, a method for preparing a waterproof material is provided, the method comprising the following steps: S1. Material preparation: Based on 100 parts of the total mass of the composite gel, the waterproof material provided by the present invention is also made of the following components: the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

[0039] In the composite cementitious material, the mass ratio of ordinary silicate cement, sulfoaluminate cement, and high-belite cement is 4-10:2-6:1; in the active penetrating component, the mass ratio of nano-silica, magnesium fluorosilicate, and chelated calcium complexing agent is 2-8:1-4:1; in the composite filler, the mass ratio of quartz sand, microsilica powder, and aged converter steel slag powder is 1.33-3:0.33-0.8:1; and in the compounding additives of the waterproof material, the mass ratio of polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, and PVA fiber is 0.25-0.625:0.08-0.25:1.

[0040] S2: Preparation method: First, put the above-mentioned ordinary silicate cement, sulfoaluminate cement, high belite cement, quartz sand, microsilica powder, and aged converter steel slag powder into a mixing device and stir at a low speed of 300-400 r / min for 10-15 min to obtain the first mixture; then add nano-silica, magnesium fluorosilicate, chelated calcium complexing agent, polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, PVA fiber, and microcapsule self-healing agent, and stir at a high speed of 600-800 r / min for 15-20 min to obtain the second mixture; then place it in a vacuum activation device and activate it at a vacuum degree of -0.08 to -0.07 MPa and a temperature of 40-50℃ for 2-2.5 h; finally, pass it through an 80-mesh standard sieve to obtain the finished product.

[0041] The waterproof material prepared by this invention has multiple advantages: First, the active components of the material can migrate deep into the concrete matrix, and the crystallization penetration depth is significantly better than that of traditional cement-based penetrating crystallizing materials, enabling long-term deep sealing of capillary seepage channels inside the concrete; Second, for 0.6mm structural through cracks, the material can maintain stable self-healing ability after repeated dry and wet cycles, and the impermeability grade of the specimens does not decrease after crack repair; Third, the mechanical properties are durable and stable, and the compressive strength at 28d, 56d, and 90d continues to increase with the curing age, without the problem of later strength reduction; Fourth, the formula introduces stabilized converter steel slag powder to replace part of the natural quartz sand, which reduces the consumption of natural mineral resources, and the system does not add additional heavy metal raw materials, resulting in low TVOC release of the finished product, and the harmful substance indicators meet GB / T 18445-2025 and HJ standards. The 456-2009 Green Building Materials Standard; finally, the entire preparation process is simple, the powder is evenly dispersed after vacuum activation treatment, the performance difference between batches of finished products is small, and it is suitable for continuous large-scale industrial production.

[0042] A third aspect of the present invention provides the application of the waterproof material as described above or the waterproof material prepared by the method described above in concrete waterproofing or crack self-repair.

[0043] The waterproof material provided by this invention, when mixed with water and applied to a concrete substrate, forms a penetrating crystalline waterproof layer. This layer is not only dense and impermeable but also possesses self-healing crack-repairing capabilities, allowing it to continue functioning throughout the concrete's service life and reducing subsequent maintenance costs. This application method is simple to operate and suitable for long-term seepage prevention and self-repair of 0.6mm structural cracks in underground engineering, water conservancy facilities, tunnels, municipal works, and kitchen / bathroom applications.

[0044] The present invention will be described in detail below through embodiments. In the following embodiments, the raw materials of the present invention are all commercially available qualified industrial products, and the preparation equipment uniformly uses a horizontal twin-shaft zero-gravity mixer, a vacuum activation tank, and an 80-mesh standard inspection sieve.

[0045] The ordinary silicate cement used in this invention is P O 52.5 grade ordinary Portland cement, conforming to GB 175-2023 "General Portland Cement".

[0046] The steel slag powder used in this invention is aged converter steel slag powder that has been naturally aged for more than 6 months and passed through 200 mesh, with an average particle size of ≤74μm. After long-term aging and grinding, the stability test was completed according to the boiling method of GB / T 1346. The judgment standard is that the test cake has no cracks, collapses, or warping.

[0047] The preparation method of the microcapsules used in the following examples and comparative examples includes: taking industrial-grade water glass with a modulus of 3.2-3.5 and a Baume degree of 38-40 and industrial-grade calcium hydroxide, and adding them into a mixing tank at a mass ratio of 2:1, stirring at 200 r / min for 30 min at room temperature, and mixing evenly to obtain basic calcium silicate core material for later use; the wall material is selected from industrial low-viscosity urea-formaldehyde resin prepolymer liquid conforming to GB / T 14732-2017 "Urea-formaldehyde, phenolic and melamine-formaldehyde resins for wood industry adhesives", with a solid content controlled at 60%-65%, which is the general specification of commercially available conventional industrial urea-formaldehyde resin. With a core material to wall material mass ratio of 1:2, the core material is dispersed in an aqueous phase and then urea-formaldehyde resin prepolymer is added. Microcapsules are prepared by in-situ polymerization. The reaction system is pre-adjusted to a weakly acidic environment of pH 4-5 and kept at a controlled temperature of 60-70℃ for 2 hours to allow the urea-formaldehyde resin to polymerize on the surface of the silicate crystalline core material to form a dense capsule wall. After washing and drying, microcapsule self-healing agent with a particle size of 50-100μm is obtained.

[0048] The following examples and comparative examples were conducted under the same environmental conditions: temperature (20±2)℃, relative humidity ≥95%.

[0049] Example 1 Material preparation: Based on a total mass of 100 parts of the composite gel, the waterproof material of this embodiment is also made of the following components: 55 parts of composite filler, 10 parts of active penetrating component, 2.2 parts of compounding agent, and 2 parts of microcapsule self-healing agent.

[0050] In the composite cementitious material, the mass ratio of ordinary silicate cement, sulfoaluminate cement, and high-belite cement is 5.95:3.31:1; in the active penetrating component, the mass ratio of nano-silicon, magnesium fluorosilicate, and chelated calcium complexing agent is 4.5:2.5:1; in the composite filler, the mass ratio of quartz sand, microsilica powder, and aged converter steel slag powder is 2:0.52:1; and in the compounding additives of the waterproof material, the mass ratio of polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, and PVA fiber is 0.4:0.15:1.

[0051] Preparation method: First, ordinary silicate cement, sulfoaluminate cement, high belite cement, quartz sand, microsilica powder, and aged converter steel slag powder are added to a mixing device and stirred at low speed of 350 r / min for 12 min to obtain the first mixture; then, nano-silica, magnesium fluorosilicate, chelated calcium complexing agent, polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, PVA fiber, and microcapsule self-healing agent are added and stirred at high speed of 700 r / min for 18 min to obtain the second mixture; then, the mixture is placed in a vacuum activation device and activated at a vacuum degree of -0.075 MPa and a temperature of 45℃ for 2.2 h; finally, it is passed through an 80-mesh standard sieve (pore size 180 μm) to obtain the finished product.

[0052] Example 2 Material preparation: Based on a total mass of 100 parts of the composite gel, the waterproof material of this embodiment is also made of the following components: 70 parts of composite filler, 5.5 parts of active penetrating component, 3 parts of compounding agent, and 1.25 parts of microcapsule self-healing agent.

[0053] In the composite cementitious material, the mass ratio of ordinary silicate cement, sulfoaluminate cement, and high-belite cement is 10:6:1; in the active penetrating component, the mass ratio of nano-silica, magnesium fluorosilicate, and chelated calcium complexing agent is 2:1:1; in the composite filler, the mass ratio of quartz sand, microsilica powder, and aged converter steel slag powder is 3:0.8:1; and in the compounding additives of the waterproof material, the mass ratio of polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, and PVA fiber is 0.25:0.08:1.

[0054] Preparation method: First, ordinary silicate cement, sulfoaluminate cement, high belite cement, quartz sand, microsilica powder, and aged converter steel slag powder are added to a mixing device and stirred at low speed (300 r / min) for 10 min to obtain the first mixture. Then, nano-silica, magnesium fluorosilicate, chelated calcium complexing agent, polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, PVA fiber, and microcapsule self-healing agent are added and stirred at high speed (600 r / min) for 15 min to obtain the second mixture. The mixture is then placed in a vacuum activation device and activated at a vacuum of -0.080 MPa and a temperature of 40℃ for 2 h. Finally, the mixture is passed through an 80-mesh standard sieve (180 μm aperture) to obtain the finished product.

[0055] Example 3 Material preparation: Based on a total mass of 100 parts of the composite gel, the waterproof material of this embodiment is also made of the following components: 45 parts of composite filler, 12 parts of active penetrating component, 1.5 parts of compounding agent, and 2.5 parts of microcapsule self-healing agent.

[0056] In the composite cementitious material, the mass ratio of ordinary silicate cement, sulfoaluminate cement, and high-belite cement is 4:2:1; in the active penetrating component, the mass ratio of nano-silica, magnesium fluorosilicate, and chelated calcium complexing agent is 8:4:1; in the composite filler, the mass ratio of quartz sand, microsilica powder, and aged converter steel slag powder is 1.5:0.35:1; and in the compounding additives of the waterproof material, the mass ratio of polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, and PVA fiber is 0.6:0.25:1.

[0057] Preparation method: First, ordinary silicate cement, sulfoaluminate cement, high belite cement, quartz sand, microsilica powder, and aged converter steel slag powder are added to a mixing device and stirred at low speed for 15 minutes at 400 r / min to obtain the first mixture; then, nano-silica, magnesium fluorosilicate, chelated calcium complexing agent, polycarboxylate-based high-efficiency water-reducing agent, hydroxypropyl methylcellulose ether, PVA fiber, and microcapsule self-healing agent are added and stirred at high speed for 20 minutes at 800 r / min to obtain the second mixture; then, the mixture is placed in a vacuum activation device and activated at a vacuum degree of -0.070 MPa and a temperature of 50℃ for 2.5 hours; finally, it is passed through an 80-mesh standard sieve (pore size 180 μm) to obtain the finished product.

[0058] Example 4 The waterproof material was prepared according to the method of Example 2, except that the active penetrating component contained only nano-silicon, while the others remained unchanged, and the finished product was obtained.

[0059] Example 5 The waterproof material was prepared according to the method of Example 2, except that the mass ratio of the nano-silicon, the magnesium fluorosilicate, and the chelated calcium complexing agent was 1:8:1, while other parameters remained unchanged, and the finished product was obtained.

[0060] Example 6 The waterproof material was prepared according to the method of Example 2, except that the microcapsule self-healing agent was directly mixed from silicate crystals and urea-formaldehyde resin, while other aspects remained unchanged, thus obtaining the finished product.

[0061] Example 7 The waterproof material was prepared according to the method of Example 2, except that the composite filler contained only quartz sand, while the others remained unchanged, thus obtaining the finished product.

[0062] Example 8 The waterproof material was prepared according to the method of Example 2, except that the mass ratio of quartz sand, silica fume and steel slag powder in the composite filler was 0.5:1:1, while other parameters remained unchanged, thus obtaining the finished product.

[0063] Example 9 The waterproof material was prepared according to the method of Example 2, except that the compound additive contained only polycarboxylate-based high-efficiency water-reducing agent, while the others remained unchanged, thus obtaining the finished product.

[0064] Example 10 The waterproof material was prepared according to the method of Example 2, except that the mass ratio of polycarboxylate superplasticizer, hydroxypropyl methylcellulose ether and PVA fiber in the compound additive was 0.1:0.5:1, while other components remained unchanged, thus obtaining the finished product.

[0065] Example 11 The waterproof material was prepared according to the method of Example 2, except that the mixing reaction was carried out under normal pressure without using a vacuum device, while other aspects remained unchanged, thus obtaining the finished product.

[0066] Comparative Example 1 The waterproof material was prepared according to the method of Example 3, except that in the composite cement, the mass ratio of the ordinary silicate cement, the sulfoaluminate cement and the high belite cement was 2.5:1.2:1, while other aspects remained unchanged, thus obtaining the finished product.

[0067] Comparative Example 2 The waterproof material was prepared according to the method of Example 3, except that in the composite cement, the mass ratio of the ordinary silicate cement, the sulfoaluminate cement and the high belite cement was 14.0:8.7:1, while other aspects remained unchanged, thus obtaining the finished product.

[0068] Comparative Example 3 The waterproof material was prepared according to the method of Example 3, except that the composite cement did not contain high-belite cement, while other aspects remained unchanged, thus obtaining the finished product.

[0069] Comparative Example 4 The waterproof material was prepared according to the method of Example 3, except that the composite cement contained only high-belite cement, while the others remained unchanged, thus obtaining the finished product.

[0070] Comparative Example 5 The waterproof material was prepared according to the method of Example 3, except that the amount of the composite filler was 30 parts, the amount of the active penetrating component was 2 parts, the amount of the compounding agent was 0.5 parts, and the amount of the microcapsule self-healing agent was 0.5 parts, while other components remained unchanged, and the finished product was obtained.

[0071] Comparative Example 6 The waterproof material was prepared according to the method of Example 3, except that the amount of the composite filler was 90 parts, the amount of the active penetrating component was 15 parts, the amount of the compounding agent was 5 parts, and the amount of the microcapsule self-healing agent was 5 parts, while other components remained unchanged, thus obtaining the finished product.

[0072] Comparative Example 7 The waterproof material was prepared according to the method of Example 3, except that the waterproof material did not contain compound additives, while other aspects remained unchanged, thus obtaining the finished product.

[0073] Test case The 28-day compressive strength, 28-day flexural strength, impermeability grade, water absorption rate, and penetration depth of each group of samples were tested according to the test methods specified in JC / T 1018-2020 "Cement-based Penetrating Crystalline Waterproofing Materials". The 56-day and 90-day long-term compressive strength, the self-healing rate of 0.6mm cracks, and the impermeability recovery rate after repair are special evaluation indicators added in this invention. The corresponding test methods are detailed below. The test results of all samples are shown in Table 1. 0.6mm crack self-healing rate test: A 0.6mm through crack was pre-cast in a standard concrete test block, coated with the waterproof material of this invention, and cured for 28 days according to standard. The water pressure method was used to test the water permeability of the crack, and the percentage of the number of impermeable test blocks to the total number of test blocks was used as the self-healing rate. Anti-seepage recovery rate after repair: The maximum anti-seepage water pressure of the repaired test block with crack and the intact standard test block were measured respectively, and the anti-seepage recovery rate was calculated by the ratio of the two water pressures. The 56d and 90d compressive strength tests followed the sample specifications and curing conditions specified in JC / T 1018-2020, only extending the curing age to the corresponding number of days for testing.

[0074] Table 1

[0075] As shown in Table 1, the waterproof materials obtained in Examples 1-3 all achieved the best performance in terms of mechanical strength, impermeability, crack self-healing, and crystal penetration. The overall performance of Examples 4-11 decreased significantly, but they still had basic waterproofing and micro-crack repair capabilities. The waterproof materials obtained in all comparative examples showed a significant decrease in strength, self-healing rate, and penetration depth.

[0076] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A waterproof material, characterized in that, The waterproof material contains composite gel, composite filler, active penetrating component, compound additives and microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

2. The waterproof material according to claim 1, characterized in that, The active penetrating component is selected from at least one of nano-silicon, magnesium fluorosilicate, and chelated calcium complexing agent; Preferably, the chelating calcium complexing agent is selected from at least one of ethanolamine, hyponitrotriacetic acid, and EDTA; Preferably, the particle size of the nano-silicon is 30-50 nm; Preferably, the active penetrating component is nano-silicon, magnesium fluorosilicate, and a chelating calcium complexing agent; Preferably, the mass ratio of the nano-silicon, the magnesium fluorosilicate, and the chelating calcium complexing agent is 2-8:1-4:

1.

3. The waterproof material according to claim 2, characterized in that, The microcapsule self-healing agent includes a core material and a wall material covering the core material. The core material is silicate crystals, and the wall material is urea-formaldehyde resin. Preferably, the particle size of the microcapsule self-healing agent is 50-100 μm.

4. The waterproof material according to any one of claims 1-3, characterized in that, The composite filler contains at least one of quartz sand, silica fume, and steel slag powder; Preferably, the composite filler contains quartz sand, silica fume, and steel slag powder; Preferably, the mass ratio of the silica sand, the silica fume, and the steel slag powder is 1.33-3:0.33-0.8:1; Preferably, the particle size of the steel slag powder is ≤74μm.

5. The waterproof material according to any one of claims 1-3, characterized in that, The compounded additive is selected from at least one of polycarboxylate superplasticizer, hydroxypropyl methylcellulose ether and PVA fiber; Preferably, the compounded additives are polycarboxylate superplasticizers, hydroxypropyl methylcellulose ethers, and PVA fibers; Preferably, the mass ratio of the polycarboxylate superplasticizer, the hydroxypropyl methylcellulose ether, and the PVA fiber is 0.25-0.625:0.08-0.25:

1.

6. A method for preparing a waterproof material, characterized in that, The method includes: mixing and reacting composite gel, composite filler, active penetrating component, compound additives and microcapsule self-healing agent; The composite cement contains ordinary silicate cement, sulfoaluminate cement, and high belite cement; the mass ratio of the ordinary silicate cement, the sulfoaluminate cement, and the high belite cement is 4-10:2-6:1; Of which, based on a total mass of 100 parts of the composite gel, the amount of the composite filler is 44-77 parts, the amount of the active penetrating component is 5-12.5 parts, the amount of the compounding auxiliary agent is 1.5-3 parts, and the amount of the microcapsule self-healing agent is 1.25-2.5 parts.

7. The preparation method according to claim 6, characterized in that, The active penetrating component is selected from at least one of nano-silicon, magnesium fluorosilicate, and chelated calcium complexing agent; Preferably, the chelating calcium complexing agent is selected from at least one of ethanolamine, hyponitrotriacetic acid, and EDTA; Preferably, the particle size of the nano-silicon is 30-50 nm; Preferably, the active penetrating component is nano-silicon, magnesium fluorosilicate, and a chelating calcium complexing agent; Preferably, the mass ratio of the nano-silicon, the magnesium fluorosilicate, and the chelating calcium complexing agent is 2-8:1-4:1; Preferably, the composite filler contains quartz sand, silica fume, and steel slag powder; Preferably, the mass ratio of the silica sand, the silica fume, and the steel slag powder is 1.33-3:0.33-0.8:1; Preferably, the particle size of the steel slag powder is ≤74μm; Preferably, the compounding additive is selected from at least one of polycarboxylate superplasticizer, hydroxypropyl methylcellulose ether, and PVA fiber; Preferably, the compounded additives are polycarboxylate superplasticizers, hydroxypropyl methylcellulose ethers, and PVA fibers; Preferably, the mass ratio of the polycarboxylate superplasticizer, the hydroxypropyl methylcellulose ether, and the PVA fiber is 0.25-0.625:0.08-0.25:

1.

8. The preparation method according to claim 6 or 7, characterized in that, The preparation method of the microcapsule self-healing agent includes: mixing the silicate crystals and the urea-formaldehyde resin, and using an in-situ polymerization method to polymerize the urea-formaldehyde resin on the surface of the silicate crystals to form a capsule wall. Preferably, the method for preparing the silicate crystals includes: mixing water glass with a modulus of 3.2-3.5 and a Baume degree of 38-40 with calcium hydroxide at a mass ratio of 2:1, and stirring at 150-250 rpm for 25-35 minutes at 10-30°C. Preferably, the mass ratio of the silicate crystals to the urea-formaldehyde resin is 1:1.5-2.5; Preferably, the conditions for the in-situ polymerization method include: adjusting the pH to 4-5, the reaction temperature to 60-70℃, and the heat preservation reaction time to 1.5-2.5h.

9. The preparation method according to claim 6 or 7, characterized in that, The conditions for the mixing reaction include: a vacuum of -0.08 to -0.07 MPa, a temperature of 40-50°C, and a time of 2-2.5 h.

10. The application of the waterproof material according to any one of claims 1-5 or the waterproof material prepared by the preparation method according to any one of claims 6-9 in concrete waterproofing or crack self-repair.

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