High-molecular polymer repair coating and preparation method thereof

Abstract

The invention provides a preparation method of a high-molecular polymer repair coating, and belongs to the technical field of coating materials. The high-molecular polymer repair coating comprises the following components in parts by mass: 800-1200 parts of 525 cement; 800 to 1200 parts of quartz sand; 1 to 5 parts of basalt fiber; 1-3 parts of a water reducing agent; 80 to 150 parts of modified epoxy emulsion; 40-120 parts of a water-based curing agent; 0.5-1 part of an auxiliary agent; and 200 to 400 parts of water. The problem of effective combination of the high-molecular polymer repairing material and the original concrete base surface is effectively solved.

Description

Technical Field

[0001] This invention provides a method for preparing a polymer repair coating, belonging to the field of coating material technology. Background Technology

[0002] Concrete-structured cross-sea bridges play a vital role in transportation. However, these bridges are exposed to harsh environmental conditions, including high salinity and strong corrosion, significant annual temperature fluctuations, and frequent freeze-thaw cycles. Consequently, varying degrees of cracking, powdering, and spalling occur on the concrete surface. If timely and effective repairs are not implemented, chloride ions from the marine environment will penetrate the concrete, inducing steel corrosion and impacting the bridge's lifespan and traffic safety.

[0003] Significant progress has been made in the research and application of polymer repair materials to resist chloride ion penetration in marine environments. For example, self-healing polymers, through the integration of built-in bacterial agents, crystalline agents, or polyurethane repair agents, automatically release and fill cracks when they appear, blocking chloride ion channels. However, the repair effect is strictly limited by crack width and healing conditions; bacterial agents are not effective in corrosion prevention; and the long-term activity and stability of repair agents face challenges. Biomimetic polymers achieve high-strength adhesion at wet interfaces, while self-healing polymers can actively seal micro-cracks, both demonstrating great potential for improving concrete durability; however, the large-scale fabrication of biomimetic structures is complex.

[0004] Therefore, this field still faces many challenges. The primary issue is the reliability of interfacial bonding under harsh conditions; damp, salt-rich concrete substrates severely affect the bond strength between the polymer and the matrix. Secondly, the long-term durability of the repair effect is questionable; the performance degradation patterns of the material under long-term wet-dry cycles, freeze-thaw cycles, and chloride erosion are not yet clear. Furthermore, the compatibility issues within the composite material system also limit its application. Future development requires more intelligent and durable material systems to meet the stringent requirements of marine engineering.

[0005] Therefore, the key to solving the problem of repair materials lies in how to effectively bond polymer repair materials with the original concrete substrate. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention proposes a polymer repair coating and its preparation method.

[0007] The technical solution of the present invention is as follows: On one hand, the present invention provides a polymer repair coating comprising the following components in parts by weight: 800-1200 parts of 525 cement; 800-1200 parts of quartz sand; 1-5 parts basalt fiber; 1-3 parts water-reducing agent; 80-150 parts of modified epoxy emulsion; 40-120 parts of water-based curing agent; 0.5-1 part of auxiliary agent; 200-400 parts water.

[0008] Basalt fiber, with its high elastic modulus, excellent tensile strength, high-temperature resistance, and good chemical stability, is widely used in concrete reinforcement materials. Nano-aqueous organic emulsions, containing numerous hydroxyl groups, can modify the surface of basalt fibers. Nanoparticles, acting as wetting agents, adhere to the fiber surface and undergo ring-opening addition reactions during hydration to form a cross-linked polymer network. This improves the wetting effect between the fiber and cementitious materials, promotes stress transfer between them, and results in excellent bond strength and flexibility. Furthermore, spherical particles and flexible films are formed within the matrix, sealing pores, enhancing matrix density, reducing shrinkage cracking caused by moisture evaporation, and thus increasing the adhesion between the fiber and cementitious materials.

[0009] Nano-aqueous organic emulsions can rapidly penetrate into the micropores and capillaries of concrete substrates through capillary action, forming an organic-inorganic interpenetrating network after the reaction, thus enhancing interfacial density. The polar groups in the nano-aqueous organic emulsions, through molecular cross-linking processes and synergistic effects with the cement hydration reaction, form hydrogen bonds and chemical bonds on the substrate surface, creating a high-density three-dimensional network structure that achieves high adhesion to concrete, metal, and other substrates.

[0010] Further improvements to this scheme resulted in a modified epoxy emulsion with a particle size distribution of 1.1–1.5 μm. The emulsion exhibits good permeability and dispersion stability, allowing for better interfacial bonding with the matrix in subsequent processes. The solid content is 50%–62%.

[0011] In a further improvement to this scheme, the particle size of the basalt fiber is 3-6 mm.

[0012] In a further improvement to this solution, the water-based curing agent is one or more of G-328 epoxy curing agent, ethylenediamine, hexamethylenediamine, and diethylenetriamine.

[0013] A further improvement to this solution is that the additive is an adhesion promoter. Specifically, it is one or more of isobutylenetriethoxysilane, n-dodecyltrimethoxysilane, and polyetheramine-dopamine biomimetic block copolymer.

[0014] A further improvement to this solution is the preparation method of the adhesion promoter polyetheramine-dopamine biomimetic block copolymer as follows: S1. Under the protection of ice water bath and nitrogen, dopamine hydrochloride and triethylamine are dissolved in anhydrous dichloromethane solution; S2. Dissolve acryloyl chloride in anhydrous dichloromethane and slowly add it dropwise to the S1 solution. After the addition is complete, restore the reaction to room temperature for 6-8 hours, and then purify to obtain the product NADA. S3. Dissolve polyetheramine and N,N'-disuccinimidyl carbonate (DSC) in anhydrous N,N-dimethylformamide (DMF). After the reaction is complete, add the reaction solution dropwise to anhydrous diethyl ether to obtain a white precipitate PEA-DSC. S4. Dissolve NADA, PEA-DSC and triethylamine in anhydrous N,N-dimethylformamide (DMF) and react to obtain the product.

[0015] Preferably, the preparation method of the adhesion promoter polyetheramine-dopamine biomimetic block copolymer is as follows: Step 1: Synthesis of the anchoring monomer - N-acryloyldopamine (NADA) The purpose of this step is to protect the primary amine group of dopamine, retaining only its catechol adhesive function, and to introduce a polymerizable acrylate end to it.

[0016] 1. Dissolve dopamine hydrochloride and triethylamine in anhydrous dichloromethane pre-cooled in an ice bath. Continuously purge the reaction system with nitrogen gas to isolate oxygen and prevent the oxidation of catechol. The molar ratio of dopamine hydrochloride to triethylamine is 1:2-3; triethylamine is used to neutralize HCl and provide an alkaline environment.

[0017] 2. Dissolve acryloyl chloride in anhydrous dichloromethane and transfer the solution to a constant-pressure dropping funnel. Under ice-water bath conditions of 0-5°C, slowly add the product from step 1 dropwise, controlling the addition time to be at least 1 hour. After the addition is complete, allow the reaction mixture to slowly warm to room temperature naturally, and continue stirring at this temperature for 8-12 hours. The molar ratio of dopamine hydrochloride to acryloyl chloride in step S2 is 1:0.9-0.99. A slight deficiency of acryloyl chloride is used to ensure that the catechol ring of dopamine is not acylated and to reduce disubstituted byproducts.

[0018] 3. The reaction solution was washed successively with pre-cooled 1M HCl solution and saturated brine. After filtration, dichloromethane was removed by rotary evaporation under reduced pressure. The crude product was recrystallized from the crude product using a mixed solvent of diethyl ether / n-hexane to obtain a solid powder.

[0019] Step 2: Activation of the macromolecular initiator - amino-terminated polyetheramine This step aims to convert the primary amino group of the polyetheramine into a highly reactive succinimide carbamate, enabling it to efficiently initiate the Michael addition polymerization of NADA.

[0020] Reaction mechanism: The amino group of polyetheramine reacts with N,N'-disuccinimidyl carbonate.

[0021] Polyetheramine and N,N'-disuccinimidyl carbonate (DSC) were dissolved in anhydrous DMF and stirred at room temperature under nitrogen protection. The reaction was continued for 6-8 hours. After the reaction was complete, the reaction solution was added dropwise to anhydrous diethyl ether to precipitate the product. The white precipitate was collected by filtration, washed thoroughly with diethyl ether, and dried under vacuum to obtain activated polyetheramine (PEA-DSC). The molar ratio of polyetheramine to DSC was 1:1-1.2, with a slight excess of DSC to ensure complete reaction.

[0022] Step 3: One-pot Michael addition polymerization to prepare polyetheramine-dopamine biomimetic block copolymer. The activated PEA-DSC is subjected to Michael addition reaction with NADA monomer to construct an ABA-type triblock structure.

[0023] Reaction mechanism: The activated carbamate in PEA-DSC undergoes Michael addition to the acrylate double bond of NADA.

[0024] Dissolve NADA, PEA-DSC, and triethylamine in anhydrous DMF. React under nitrogen protection and in an oil bath at 40-45°C with continuous stirring for 24-36 hours. The molar ratio of NADA to PEA-DSC is 3:1, and the molar ratio of NADA to triethylamine is 70-80:1.

[0025] After the reaction was complete, the reaction solution was cooled to room temperature. The reaction solution was then slowly added dropwise to an excess of diethyl ether under vigorous stirring to precipitate the copolymer. Drying yielded the final product, a polyetheramine-dopamine biomimetic block copolymer.

[0026] This polyetheramine-dopamine biomimetic block copolymer has a triblock structure: Segment A (anchoring end): contains multiple catechol (a characteristic structure of dopamine) blocks for strong adhesion to inorganic substrates (including damp surfaces). Segment B (flexible segment): a polyetheramine chain that provides flexibility and participates in the curing of the epoxy system. Segment C (reactive end): amino-terminated, capable of undergoing a curing reaction with epoxy groups, firmly embedded in the polymer network.

[0027] This copolymer mimics the catechol chemistry of marine mussel adhesive proteins, providing extremely strong and universal adhesion to wet substrates, solving the core challenge of wet marine environments. The introduction of reversible chemical bonds (dynamic covalent bonds) allows the coating to redistribute stress under stress or thermal expansion and contraction, preventing debonding caused by stress concentration at the interface, thereby improving durability and impact resistance. One end of the molecule firmly bonds to the inorganic substrate (concrete), while the other end forms a chemical crosslink with the organic coating (modified epoxy emulsion).

[0028] On the other hand, the present invention provides a method for preparing the above-mentioned polymer repair coating, comprising the following steps: (1) The basalt fiber is soaked and stirred evenly with modified epoxy emulsion, the excess slurry is squeezed off, and then dried to obtain modified basalt fiber; the surface of the basalt fiber is modified with modified epoxy emulsion, and after drying, a dense film is formed on the fiber surface, which contains hydrophilic groups such as hydroxyl groups.

[0029] (2) Mix cement, quartz sand and modified basalt fiber evenly to form fiber powder; (3) Dissolve the water-reducing agent, then add the modified epoxy emulsion, water-based curing agent and additives in sequence, and stir thoroughly. (4) Pour the liquid that was stirred evenly in step (3) into the fiber powder to obtain a uniform and stable repair slurry.

[0030] There is no requirement for the order of steps (2) and (3).

[0031] In a further improvement to this scheme, in step (1), basalt fibers are soaked in modified epoxy emulsion for 2 hours, and after soaking, excess slurry is squeezed out and dried at 130 degrees.

[0032] In a further improvement of this scheme, the mixing speed in step (2) is 2000-3000 r / min and the mixing time is 15-20 min; in step (3), the mixing speed is 1000-2000 r / min and the mixing time is 5-10 min.

[0033] The beneficial effects of this invention are as follows: This invention utilizes modified epoxy emulsion to modify the surface of basalt fibers, improving their compatibility with the inorganic matrix and reducing interfacial defects. Then, modified epoxy emulsion and a water-based curing agent are added to the sand powder to enhance the interfacial bonding between the fibers and the matrix. After curing with the modified water-based epoxy emulsion and water-based curing agent, a three-dimensional network structure is formed in the repair material, increasing the adhesion between organic and inorganic materials, bridging the fibers and the sand powder matrix, improving stress transfer efficiency, and inhibiting crack propagation. The flexibility of the epoxy resin complements the high strength of the basalt fibers, enhancing crack resistance while maintaining the rigidity of the matrix. The use of a water-based curing agent and epoxy emulsion reduces VOC emissions, protects the environment, and aligns with the trend of green building materials. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 SEM images of basalt fiber before and after modification in Example 3 (left), before modification (right), and after modification.

[0036] Figure 2 The compressive and flexural strengths are those of Example 3. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0038] This invention provides a molecular polymer repair composite material, comprising components in parts by mass of the following: 800-1200 parts of 525 cement; 800-1200 parts of quartz sand; 1-5 parts basalt fiber; 1-3 parts water-reducing agent; 80-150 parts of modified epoxy emulsion; 40-120 parts of water-based curing agent; 0.5-1 part of auxiliary agent; 200-400 parts water.

[0039] The modified epoxy emulsion has a particle size distribution of 1.1~1.5µm and a solid content of 50%-62%.

[0040] The basalt fibers have a particle size of 3-6 mm.

[0041] Among them, 525 cement is selected from Shanshui Group, quartz sand is selected from Shandong High Purity Quartz Sand Co., Ltd., basalt fiber is selected from Shandong Juyuan Basalt Fiber Co., Ltd., water-reducing agent is selected from Shandong Guoqiao Building Materials Technology Co., Ltd., naphthalene-based water-reducing agent FDN-A, water-based curing agent is selected from Mitsubishi Gas Chemical Trading (Shanghai) Co., Ltd., G-328 epoxy curing agent, modified epoxy emulsion is selected from Shandong Ruisan Chemical Technology Co., Ltd., WE-8236 water-based epoxy resin emulsion, and the additive isobutylene triethoxysilane is selected from Jiangsu Wojia New Material Technology Co., Ltd.

[0042] Example 1 Mix 525 cement and quartz sand thoroughly at a ratio of 1:1 to obtain a uniformly mixed powder. Basalt fibers were soaked in a modified epoxy emulsion for 2 hours. After soaking, excess slurry was squeezed out, and the mixture was dried at 130 degrees Celsius. Then, the basalt fibers were stirred with the powder at a speed of 2000 rpm for 15 minutes to ensure thorough mixing. The modified epoxy emulsion used here is the same as that added later; it is only for surface modification and therefore used in very small quantities.

[0043] The water-reducing agent was dissolved in water, and then a modified epoxy emulsion, a water-based curing agent, and an additive were added and dispersed at high speed to obtain a mixed emulsion. The mixing speed was 2000 r / min, and the mixing time was 5 min. The additive was isobutylenetriethoxysilane.

[0044] Take 1500g of the above uniformly mixed fiber powder (749g of 525 cement, 749g of quartz sand, and 2g of basalt fiber) and place it in a mixing container. Add 350g of mixed emulsion (containing 27.5g of modified epoxy emulsion, 10g of water-based curing agent, 2g of water-reducing agent, 0.8g of additives, and 309.7g of water) and stir at 2000r / min for 2-3 minutes. After the reaction is complete, a viscous slurry is formed.

[0045] Example 2 The difference from Example 2 is that 350g of mixed emulsion (containing 60g of modified epoxy emulsion, 23g of water-based curing agent, 2g of water-reducing agent, 0.8g of additives, and 264.2g of water) was added. Example 3 The difference from Example 2 is the addition of 350g of a mixed emulsion (containing 75g of modified epoxy emulsion, 50g of water-based curing agent, 2g of water-reducing agent, 0.8g of additives, and 222.2g of water). SEM images of the basalt fiber before and after modification are shown below (left), before modification (right). Figure 1 As shown in the figure, the surface of the basalt fiber undergoes significant changes after modification. The compressive and flexural strengths of the obtained polymer repair coating after solidification are as follows: Figure 2 As shown.

[0046] Comparative Example 1 The difference from Example 3 is the addition of 350g of mixed emulsion (2g water-reducing agent, 0.8g additive, and 347.2g water). Comparative Example 2 The difference from Example 3 is the addition of 350g of mixed emulsion (2g water-reducing agent, 348g water). Comparative Example 3 The difference from Example 3 is the addition of 350g of mixed emulsion (containing 75g of modified epoxy emulsion, 50g of water-based curing agent, 2g of water-reducing agent, and 223g of water). Comparative Example 4 Unlike Example 3, no basalt fiber was added.

[0047] Example 4 The difference from Example 3 is that the additive is a polyetheramine-dopamine biomimetic block copolymer.

[0048] The synthesis method of polyetheramine-dopamine biomimetic block copolymer is as follows: Step 1: Synthesis of the anchoring monomer - N-acryloyldopamine (NADA) 1. Dissolve 52.8 mmol of dopamine hydrochloride and 132 mmol of triethylamine in 150 mL of anhydrous dichloromethane pre-cooled in an ice bath. Continuously purge the reaction system with nitrogen gas to isolate it from oxygen.

[0049] 2. Dissolve 48 mmol of acryloyl chloride in 50 mL of anhydrous dichloromethane and transfer the solution to a constant-pressure dropping funnel. Under an ice-water bath at 0-5°C, slowly add the solution from step 1, controlling the addition time to 1-1.2 hours. After the addition is complete, allow the reaction mixture to slowly warm to room temperature (approximately 25°C) naturally, and continue stirring at this temperature for 10 hours.

[0050] 3. The reaction solution was washed successively with pre-cooled 1M HCl solution and saturated brine. After filtration, dichloromethane was removed by rotary evaporation under reduced pressure. The crude product was recrystallized from the crude product using a mixed solvent of diethyl ether / n-hexane to obtain a solid powder.

[0051] Step 2: Activation of the macromolecular initiator - amino-terminated polyetheramine 50 mmol of polyetheramine and 56 mmol of N,N'-disuccinimidyl carbonate (DSC) were dissolved in 100 mL of anhydrous DMF and stirred at room temperature (25°C) under nitrogen protection. The reaction was continued for 7 hours. After the reaction was completed, the reaction solution was added dropwise to 500 mL of anhydrous diethyl ether to precipitate the product. The white precipitate was collected by filtration, washed thoroughly with diethyl ether, and dried under vacuum to obtain activated polyetheramine (PEA-DSC).

[0052] Step 3: One-pot Michael addition polymerization to prepare polyetheramine-dopamine biomimetic block copolymer 66 mmol NADA, 22 mmol PEA-DSC, and 2 mmol triethylamine were dissolved in 150 mL of anhydrous DMF. The reaction was carried out under nitrogen protection and in an oil bath at 40°C with continuous stirring for 30 hours.

[0053] After the reaction was complete, the reaction solution was cooled to room temperature. The reaction solution was then slowly added dropwise to an excess of diethyl ether under vigorous stirring to precipitate the copolymer. Drying yielded the final product, a polyetheramine-dopamine biomimetic block copolymer.

[0054] Example 5: Pull-out bond strength test C50 concrete test blocks were used uniformly. Before testing, the bonding surface was roughened to ensure it was rough, clean, and dry. The polymer repair coating material of this invention was applied to the C50 concrete test blocks using a scraping method, with the coating thickness controlled to be uniform (3mm).

[0055] Test Method: Following ASTM C1583 / C1583M, a 50mm diameter steel pull-out head was bonded to the cured coating surface using high-strength epoxy adhesive. The specimen was placed in a tensile testing machine, and a tensile force was applied at a constant rate (0.8 MPa / s) until failure. The maximum pull-out force was recorded, and the bond strength (pull-out force / pull-out head area) was calculated. The test results are shown in Table 1.

[0056] Table 1 Group Initial bond strength (MPa) Comparative Example 2 1.2 Comparative Example 1 1.8 Comparative Example 3 3.0 Comparative Example 4 4.2 Example 1 3.3 Example 2 3.8 Example 3 4.3 Example 4 4.8 Comparative analysis revealed that Comparative Example 1 (without emulsion, 1.8 MPa) and Comparative Example 3 (with emulsion but no additives, 3.0 MPa) both showed improvements over Comparative Example 2, with Comparative Example 3 showing a significant improvement. This demonstrates that the emulsion is the primary source of adhesive strength. The nano-aqueous organic emulsion of this invention contains a large number of hydroxyl groups, which can modify the surface of organic or inorganic fibers in the repair material. The nanoparticles act as a wetting agent, adhering to the fiber surface. During hydration, a ring-opening addition reaction occurs simultaneously, generating a cross-linked polymer network, improving the wetting effect between the fiber and the cementitious material, promoting stress transfer between the fiber and the cementitious material, and exhibiting excellent bonding strength and flexibility. It forms spherical particles and a flexible film in the matrix, sealing pores, enhancing the density of the matrix, reducing shrinkage cracking caused by moisture evaporation, and thus increasing the adhesion force at the fiber-cementitious material interface.

[0057] Nano-aqueous organic emulsions can rapidly penetrate into the micropores and capillaries of concrete matrices through capillary action, forming an organic-inorganic interpenetrating network after the reaction, enhancing interfacial density. The polar groups in the nano-aqueous organic emulsion, through molecular cross-linking and synergistic effects with cement hydration, form hydrogen bonds and chemical bonds on the substrate surface, creating a high-density three-dimensional network structure that achieves strong adhesion to concrete, metal, and other substrates. It possesses excellent physical, mechanical, and electrical insulation properties, strong adhesion, and is also resistant to impermeability, freeze-thaw cycles, salt, alkali, and weak acid corrosion. It can be applied to damp substrates without drying and can harden in humid environments or underwater; it is non-flammable, non-explosive, and environmentally friendly, posing no harm to human health; it is easy to apply and can be cleaned with water, exhibiting strong environmental adaptability and meeting the surface protection requirements of concrete, thus finding wide application in the building materials industry.

[0058] Compared with Comparative Example 3 (without additives, 3.0 MPa) and Example 3 (with silane, 4.3 MPa), the strength was increased by about 43%, demonstrating the key improvement of interfacial properties by silane additives.

[0059] From Example 1 (3.3 MPa), Example 2 (3.8 MPa), and Example 3 (4.3 MPa), the strength steadily increased with the increase of emulsion dosage, demonstrating a clear dose dependence.

[0060] The strength of Example 4 (4.8 MPa) is about 12% higher than that of the best silane system Example 3 (4.3 MPa), indicating that the polyetheramine-dopamine biomimetic block copolymer has better adhesion.

[0061] Example 6: Accelerated Aging Test under Simulated Service Environment The system employs a combined cycle of "humid heat-salt spray-drying-freezing," with each cycle lasting 24 hours, simulating the harsh conditions of the marine environment.

[0062] Step 1: Chloride soaking (4 hours): Immerse the test block in a 3.5% NaCl solution at a temperature of 40°C.

[0063] Step 2: Moist heat curing (4 hours): After taking it out, place it in a constant temperature and humidity chamber at 40°C and 95%RH.

[0064] Step 3: Drying (8 hours): Place in a 60°C forced-air oven for drying.

[0065] Step 4: Freeze (8 hours): Place in a freezer at -20°C to freeze.

[0066] Test cycle: 30 cycles. After 30 cycles, a predetermined number of test blocks were taken from each group for pull-out bond strength testing. The test results are shown in Table 2.

[0067] Table 2 Group Strength (MPa) after 30 cycles Strength retention rate (%) Comparative Example 2 0.4 33% Comparative Example 1 0.9 50% Comparative Example 3 2.1 70% Comparative Example 4 3.2 76% Example 1 2.5 76% Example 2 3.1 82% Example 3 3.7 86% Example 4 4.4 92% Comparative Example 2: The pure cement system deteriorated rapidly under multi-factor aging, and the bonding interface completely failed. Comparative Example 1: Silane provided hydrophobicity, delaying the intrusion of moisture and salt, but the material itself was not resistant to freeze-thaw cycles and wet-dry stress, resulting in severe performance degradation. Comparative Example 3: The epoxy emulsion provided a polymer network that effectively inhibited the generation and propagation of microcracks and resisted physical stress, thus achieving a significantly higher retention rate than the previous two. However, weak points at the interface allowed chloride ion intrusion, causing a continuous decline in performance in the later stages. Examples 1-3: The epoxy emulsion was responsible for crack resistance and toughening. The silane additive was responsible for waterproofing and interface strengthening. The combination of the two formed a dual protection mechanism of bulk strengthening and interface protection. The higher the emulsion dosage, the stronger and tougher the bulk; the better the protective effect in synergy with silane. Example 4: Its ultra-high retention rate stemmed from the ultra-stable interface created by the biomimetic copolymer. This interface is resistant to hydrolysis and salt corrosion, and exhibits minimal performance degradation in aging environments. It can more effectively block chloride ions and moisture from reaching the interface, protecting the "foundation" of the bond. The strong interfacial bonding makes the whole system more integrated when subjected to freeze-thaw cycles and thermal stress, avoiding localized damage.

[0068] Meanwhile, as can be seen from Comparative Example 4, in static, short-term pull-out tests, the load is dominated by polymer bonding force and cement hydration products. The bridging and toughening effects of the fibers have not been fully activated. Therefore, the presence or absence of fibers has little direct impact on the initial bond strength. After 30 aging cycles, the strength of Comparative Example 4 (3.2 MPa) is lower than that of Example 3 (3.7 MPa), and its attenuation trend intensifies with continued cycling, indicating that basalt fibers play a crucial role in the long-term durability test. Materials without fibers are brittle, and once cracks occur, they propagate rapidly, leading to failure. Materials with fibers are tough; crack propagation requires overcoming the pull-out work of the fibers, consuming more energy, thus significantly improving the toughness of the material. Under freeze-thaw cycles and wet-dry heat stress, micro-stresses are generated inside the repair material. In Comparative Example 4 without fibers, these stresses directly lead to the formation of micro-cracks. In Example 3, the basalt fibers are three-dimensionally randomly distributed in the material, acting like a skeleton, effectively bridging these micro-cracks and preventing them from propagating into macro-cracks.

[0069] Example 7: The difference from Example 4 is that the raw material dosage is: 800g of 525 cement; 800g of quartz sand; 1g of basalt fiber; 1g of water-reducing agent; 80g of modified epoxy emulsion; 40g of water-based curing agent; 0.5g of additives; and 200g of water. Its initial bond strength is 4.4 MPa, and the strength retention rate after 30 cycles is 90%.

[0070] Example 8: The difference from Example 4 is that the raw material dosage is: 1200g of 525 cement; 1200g of quartz sand; 5g of basalt fiber; 3g of water-reducing agent; 150g of modified epoxy emulsion; 120g of water-based curing agent; 1g of additives; and 400g of water. Its initial bond strength is 4.6 MPa, and the strength retention rate after 30 cycles is 92%.

[0071] Example 9: The difference from Example 4 is that the raw material usage is as follows: 1000g of 525 cement; 1000g of quartz sand; 3g of basalt fiber; 2g of water-reducing agent; 100g of modified epoxy emulsion; 80g of water-based curing agent; 0.8g of additives; and 300g of water. Its initial bond strength is 5.0 MPa, and the strength retention rate after 30 cycles is 95%.

[0072] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high polymer polymeric repair coating characterized by: Comprise the following components by mass fraction: 525 cement 800~1200 parts; Quartz sand 800~1200 parts; Basalt fiber 1~5 parts; Water reducing agent 1~3 parts; Modified epoxy emulsion 80~150 parts; Water-based curing agent 40~120 parts; Auxiliary agent 0.5-1 parts; Water 200~400 parts.

2. The polymeric polymer repair coating of claim 1, wherein: The modified epoxy emulsion has a particle size of 1.1-1.5um and a solid content of 50%-62%.

3. The polymeric polymer repair coating of claim 1, wherein: The basalt fiber has a particle size of 3-6mm.

4. The polymeric polymer repair coating of claim 1, wherein: The auxiliary agent is one or more of isobutylene triethoxysilane, n-dodecyl trimethoxysilane, and polyether amine-dopamine biomimetic block copolymer.

5. The polymeric polyblend washcoat coating of claim 4 wherein: The preparation method of the polyether amine-dopamine biomimetic block copolymer is as follows: S1, under ice water bath and nitrogen protection, dopamine hydrochloride and triethylamine are dissolved in anhydrous dichloromethane solution; S2, acryloyl chloride is dissolved in anhydrous dichloromethane, slowly added to the S1 solution, after the addition is completed, the temperature is restored to room temperature for 6-8 hours, and then purified to obtain the product NADA; S3, polyether amine and N,N'-disuccinimidyl carbonate are dissolved in anhydrous N,N-dimethylformamide, and after the reaction is completed, the reaction solution is added to anhydrous ether to obtain white precipitate PEA-DSC; S4, NADA, PEA-DSC and triethylamine are dissolved in anhydrous N,N-dimethylformamide to obtain the product.

6. The polymeric polyblend washcoat coating of claim 5, wherein: In step S1, the molar ratio of dopamine hydrochloride to triethylamine is 1:2-3, and in step S2, the molar ratio of dopamine hydrochloride to acryloyl chloride is 1:0.9-0.99; in step S3, the molar ratio of polyether amine to N,N'-disuccinimidyl carbonate is 1:1-1.

2.

7. The polymeric polyblend washcoat coating of claim 5 wherein: In step S4, the molar ratio of NADA to PEA-DSC is 3:1, and the molar ratio of NADA to triethylamine is 70-80:

1.

8. The method for preparing a polymer repair coating according to any one of claims 1-7, characterized in that, Comprise the following steps: (1) The basalt fiber is soaked with the modified epoxy emulsion and stirred uniformly, the excess slurry is squeezed out, and then dried to obtain modified basalt fiber; (2) The cement, quartz sand and modified basalt fiber are stirred and mixed uniformly to form a fiber powder; (3) The water reducing agent is dissolved, and then the modified epoxy emulsion, water-based curing agent and auxiliary agent are added in sequence and stirred uniformly; (4) The liquid stirred uniformly in step (3) is poured into the fiber powder to obtain a uniform and stable repair slurry; The steps (2) and (3) have no sequence requirement.

9. The method for preparing a polymer repair coating according to claim 8, characterized in that, In step (1), the basalt fiber is soaked in the modified epoxy emulsion for 2h, the excess slurry is squeezed out after soaking, and dried at 130 degrees.

10. The method for preparing a polymer repair coating according to claim 8, characterized in that, In step (2), the mixing speed is 2000-3000r / min, and the mixing time is 15~20min; in step (3), the mixing speed is 1000-2000r / min, and the mixing time is 5~10min.

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