Waterproof and anticorrosive coating for concrete and preparation method thereof
By using inorganic-organic composite coatings and modified graphene oxide, the limitations of concrete coatings in terms of waterproofing and corrosion protection have been overcome, and the overall performance of the coatings has been improved, especially their density and waterproofing and corrosion protection effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING LIGAO LIDE ROAD & BRIDGE WATERPROOFING MATERIALS
- Filing Date
- 2024-06-11
- Publication Date
- 2026-07-21
AI Technical Summary
Existing concrete coatings have limitations in terms of waterproofing and corrosion protection, especially inorganic and organic coatings which have insufficient interfacial adhesion, and epoxy coatings which have problems such as micropore formation and low weather resistance during the curing process.
An inorganic-organic composite coating is adopted, which combines acrylate polymers with epoxy resins and modifies graphene oxide to improve dispersibility. The high hardness of epoxy resin and the high flexibility of acrylate polymers are combined to improve the coating's density, penetration resistance and adhesion.
It improves the durability, weather resistance, corrosion resistance and adhesion of the coating, enhances the density and waterproof and anti-corrosion properties of the coating, and improves the dispersibility of graphene oxide in organic solvents and its compatibility with resins.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of coating composition technology, and in particular to a waterproof and anti-corrosion coating for concrete and its preparation method. Background Technology
[0002] Concrete structures, due to their porous and rough surface, are susceptible to corrosion from environmental factors such as carbon dioxide, moisture, and salt, leading to cracking and carbonation. Chloride ions, in particular, accelerate the corrosion of reinforcing steel within the concrete, negatively impacting the durability of the concrete structure. Therefore, appropriate protective measures are crucial to extending the service life of concrete structures and ensuring their safety. Coating is a simple and effective protective method. Waterproofing primarily prevents moisture erosion and damage to the concrete, while corrosion protection primarily prevents chemical corrosion.
[0003] CN202210915407.1 relates to the field of architectural coatings, specifically a waterproof and anti-corrosion coating for concrete and its preparation method. This invention prepares a waterproof and anti-corrosion coating for concrete, using water-based fluorocarbon resin as the base material, improving its hydrophilicity with water-based hydroxyl acrylic resin, and using a self-made self-cleaning composite material to improve its dust removal and pollutant degradation capabilities. This results in a novel coating that possesses the advantages of fluorocarbon coatings—waterproofing, anti-corrosion, high weather resistance, and chemical resistance—while also exhibiting dust-repellent and self-cleaning properties. Another invention uses nano-silica as the base material, loading a layer of silicotungstic acid onto the surface of the nano-silica, using trimethylsilimidazole as a modifier, and sodium EDTA and sodium dodecylbenzenesulfonate as surfactants, resulting in a self-cleaning composite material with good dispersibility and excellent photocatalytic performance.
[0004] CN202111585217.X relates to the field of coatings, specifically disclosing a penetrating waterproof coating for concrete protection, comprising the following raw materials in parts by weight: 30-55 parts cement, 5-12 parts quartz sand, 2-6 parts tetraneedle-shaped zinc oxide whiskers, 1-3 parts dispersant, 26-40 parts filler, and 5.5-13 parts composite waterproofing agent. The composite waterproofing agent comprises the following raw materials in parts by weight: 2.5-4.5 parts silicon-derived inorganic matter, 0.5-1.5 parts hydrogenated polyisobutylene, and 2.5-7 parts siloxane polymer. The filler includes hydrotalcite powder, silica sol, and pyrophyllite powder. When the coating obtained from this application is applied to concrete, it can quickly penetrate into the concrete interior, blocking and sealing capillary pores while repairing micro-cracks, improving the waterproofing effect of the concrete. Simultaneously, it can effectively improve the secondary impermeability and compressive strength of the concrete, thus extending its service life.
[0005] However, fluorine-containing materials in organic coatings can pollute the environment, while inorganic coatings mainly form films with cement. These coatings have good breathability, allowing water vapor inside the concrete to circulate more easily and reducing the likelihood of expansion stress. They are water-based and environmentally friendly coatings. However, due to the presence of an interface transition zone, the adhesion between the new and old cement materials is slightly insufficient, which can lead to poor performance when used on concrete surfaces. Summary of the Invention
[0006] In view of the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a waterproof and anti-corrosion coating for concrete and a method for preparing the same.
[0007] Both inorganic and organic coatings have certain performance limitations. To overcome the shortcomings of a single coating and improve its overall performance, inorganic and organic coatings can be combined to achieve complementary advantages, improving durability, weather resistance, corrosion resistance, and adhesion. Inorganic-organic composite coatings combine the high hardness and abrasion resistance of inorganic coatings with the high flexibility and adhesion of organic coatings. During the preparation process, inorganic particles can fill the voids in the organic coating, improving its density and impermeability; simultaneously, the organic coating can encapsulate the inorganic particles, improving the flexibility and adhesion of the inorganic coating. Epoxy resin coatings are the most widely used anti-corrosion coatings due to their excellent mechanical properties, abrasion resistance, insulation, and stability under acidic and alkaline conditions. However, epoxy coatings still have some limitations, such as micropores formed during curing, low weather resistance, low toughness, and decreased adhesion after long-term use, all of which can lead to coating performance failure. This invention provides an acrylate polymer for composite with epoxy resin to improve the adhesion and waterproof / corrosion resistance of the epoxy resin. The various active groups in the acrylate polymer can react with the epoxy resin matrix and curing agent to increase the degree of cross-linking, making the coating surface denser and preventing moisture or chloride ions from penetrating the coating. The long alkyl chains in the acrylate polymer enhance the hydrophobicity of the coating, further improving its performance. Modified graphene oxide improves its poor dispersibility and tendency to agglomerate in solvents through modification. Grafting alkyl chains improves its dispersibility in organic solvents, and the amino groups at the grafted ends can further react with the epoxy resin matrix, enhancing its compatibility with the resin material. The high strength of graphene itself, along with its ability to enhance gel porosity, reduce large capillaries, bridge microcracks, and inhibit their further propagation, effectively improves the mechanical and chemical properties of the coating.
[0008] To achieve the above objectives, the present invention provides a waterproof and anti-corrosion coating for concrete, comprising components A and B, wherein component A comprises: 10-25 parts of acrylate polymer, 75-100 parts of epoxy resin, 1-10 parts of modified graphene oxide, 0.5-3 parts of leveling agent, 0.5-3 parts of dispersant, 0.5-1 part of defoamer, and 20-50 parts of solvent; and component B comprises 10-40 parts of curing agent.
[0009] Furthermore, the leveling agent is BYK-300.
[0010] Furthermore, the dispersant is BYK-P104S.
[0011] Furthermore, the defoamer is BYK-070.
[0012] Furthermore, the solvent is one of acetone, ethyl acetate, and ethylene glycol butyl ether.
[0013] Furthermore, the curing agent is one of ethylenediamine, diethylenetriamine, diethylaminopropylamine, or phenolic amine curing agents.
[0014] The method for preparing the acrylate polymer includes the following steps:
[0015] Methyl methacrylate, lauryl acrylate, octadecyl acrylate, glycidyl methacrylate, and [2-oxo-2-[2-(2-oxoimidazol-1-yl)ethylamino]ethyl]2-methylprop-2-enoate were mixed in a molar ratio of 2-5:1-4:1-3:0.5-2:0.5-2 and stirred until homogeneous to obtain a mixture. Then, 0.5-2 wt% of azobisisobutyronitrile was added to the mixture, and the mixture was stirred until homogeneous. One-fifth of the mixture was then mixed with an equal volume of ethyl acetate and 0.1-0.2 wt% of dodecanethiol. The mixture was heated and stirred under an inert atmosphere to carry out polymerization. The remaining mixture was then added in batches, and stirred for 10-30 min after each addition. After all the mixture was added, stirring was continued for 20-30 min to obtain the final product.
[0016] Furthermore, the heating temperature range is 85–95°C.
[0017] Preferably, the method for preparing the acrylate polymer includes the following steps:
[0018] Methyl methacrylate, lauryl acrylate, octadecyl acrylate, glycidyl methacrylate, and [2-oxo-2-[2-(2-oxoimidazol-1-yl)ethylamino]ethyl]2-methylprop-2-enoate were mixed in a molar ratio of 2-5:1-4:1-3:0.5-2:0.5-2 and stirred until homogeneous. Then, 0.5-2 wt% of the mixture of azobisisobutyronitrile was added and stirred until homogeneous. One-fifth of the mixture was then mixed with an equal volume of ethyl acetate and 0.1-0.2 wt% of the mixture of dodecanethiol. The mixture was heated to 85-95°C under an inert atmosphere and stirred to polymerize. The remaining mixture was then added in batches, with stirring for 10-30 min after each addition. After all the mixture was added, stirring was continued for 20-30 min to polymerize the final product.
[0019] The method for preparing the modified graphene oxide includes the following steps:
[0020] 1,12-Diaminododecane was added to anhydrous ethanol and stirred until dissolved. Then, an equal volume of graphene oxide aqueous dispersion was added, and the mixture was heated to 80–90 °C and stirred for 6–10 h. After cooling to room temperature, the mixture was centrifuged, and the lower precipitate was washed with ethanol and dried to obtain the final product.
[0021] Furthermore, the mass ratio of 1,12-diaminododecane to graphene oxide is 1:1.
[0022] Preferably, the method for preparing the modified graphene oxide includes the following steps:
[0023] 1,12-Diaminododecane was added to anhydrous ethanol and stirred until dissolved. Then, an equal volume of aqueous dispersion of graphene oxide was added. The mass ratio of 1,12-diaminododecane to graphene oxide was 1:1. The mixture was heated to 80–90 °C and stirred for 6–10 h. After cooling to room temperature, the mixture was centrifuged. The lower precipitate was washed with ethanol and dried to obtain the final product.
[0024] A method for preparing a waterproof and anti-corrosion coating for concrete includes the following steps:
[0025] After mixing the acrylate polymer, epoxy resin, modified graphene oxide, leveling agent, dispersant, defoamer, and solvent according to the specified ratio, the mixture is stirred evenly to obtain component A. Component A is then mixed with component B and stirred evenly to obtain the final product.
[0026] The beneficial effects of this invention are:
[0027] This invention improves the defects of poor toughness and high porosity of epoxy resin by modifying epoxy resin and graphene oxide, and enhances the dispersibility of graphene oxide in coatings. The resulting coating has good waterproofness, excellent corrosion resistance, and good mechanical properties. Detailed Implementation
[0028] Epoxy resin, model: E44, Baling Petrochemical.
[0029] Curing agent, model: T31, Guangzhou Qirui Chemical Co., Ltd.
[0030] Graphene oxide, particle size: 1-10 μm, Shenzhen Turing Evolution Technology Co., Ltd.
[0031] Compare with Example 1
[0032] A method for preparing a waterproof and anti-corrosion coating for concrete includes the following steps:
[0033] A1. Methyl methacrylate, lauryl acrylate, octadecyl acrylate, glycidyl methacrylate, and [2-oxo-2-[2-(2-oxoimidazol-1-yl)ethylamino]ethyl]2-methylprop-2-enoate were mixed in a molar ratio of 4:3:2:0.5:0.55 and stirred until homogeneous to obtain a mixture. Then, 0.8 wt% of azobisisobutyronitrile was added to the mixture, and the mixture was stirred until homogeneous. One-fifth of the mixture was then mixed with an equal volume of ethyl acetate and 0.15 wt% of dodecanethiol. The mixture was heated to 90°C under nitrogen and stirred until homogeneous to carry out polymerization. The remaining mixture was then added in batches, and stirred for 20 min after each addition. After all the mixture was added, stirring was continued for 30 min to obtain the acrylate polymer.
[0034] A2. By weight, mix 20 parts of acrylate polymer, 100 parts of epoxy resin E44, 3 parts of graphene oxide, 1 part of BYK-300, 2 parts of BYK-P104S, 0.8 parts of BYK-070, and 45 parts of acetone, and stir until homogeneous to obtain component A. Mix component A with 30 parts of T31 curing agent and stir until homogeneous to obtain the final product.
[0035] Compare with Example 2
[0036] A method for preparing a waterproof and anti-corrosion coating for concrete includes the following steps:
[0037] A1. Add 1,12-diaminododecane to anhydrous ethanol, stir to dissolve, and then add an equal volume of graphene oxide aqueous dispersion. The mass ratio of 1,12-diaminododecane to graphene oxide is 1:1. Heat to 85℃ and stir for 8 hours. After cooling to room temperature, centrifuge to separate the precipitate. The lower precipitate is washed with ethanol and dried to obtain modified graphene oxide.
[0038] A2. By weight, mix 100 parts of epoxy resin E44, 3 parts of modified graphene oxide, 1 part of BYK-300, 2 parts of BYK-P104S, 0.8 parts of BYK-070, and 45 parts of acetone, and stir until homogeneous to obtain component A. Mix component A with 30 parts of T31 curing agent and stir until homogeneous to obtain the final product.
[0039] Example 1
[0040] A method for preparing a waterproof and anti-corrosion coating for concrete includes the following steps:
[0041] A1. Methyl methacrylate, lauryl acrylate, octadecyl acrylate, glycidyl methacrylate, and [2-oxo-2-[2-(2-oxoimidazol-1-yl)ethylamino]ethyl]2-methylprop-2-enoate were mixed in a molar ratio of 4:3:2:0.5:0.55 and stirred until homogeneous to obtain a mixture. Then, 0.8 wt% of azobisisobutyronitrile was added to the mixture, and the mixture was stirred until homogeneous. One-fifth of the mixture was then mixed with an equal volume of ethyl acetate and 0.15 wt% of dodecanethiol. The mixture was heated to 90°C under nitrogen and stirred until homogeneous to carry out polymerization. The remaining mixture was then added in batches, and stirred for 20 min after each addition. After all the mixture was added, stirring was continued for 30 min to obtain the acrylate polymer.
[0042] A2. Add 1,12-diaminododecane to anhydrous ethanol, stir to dissolve, and then add an equal volume of graphene oxide aqueous dispersion. The mass ratio of 1,12-diaminododecane to graphene oxide is 1:1. Heat to 85℃ and stir for 8 hours. After cooling to room temperature, centrifuge to separate the precipitate. The lower precipitate is washed with ethanol and dried to obtain modified graphene oxide.
[0043] A3. By weight, mix 20 parts of acrylate polymer, 100 parts of epoxy resin E44, 3 parts of modified graphene oxide, 1 part of BYK-300, 2 parts of BYK-P104S, 0.8 parts of BYK-070, and 45 parts of acetone, and stir until homogeneous to obtain component A. Mix component A with 30 parts of T31 curing agent and stir until homogeneous to obtain the final product.
[0044] Example 2
[0045] Same as Example 1, except that glycidyl methacrylate was not added in the preparation of the acrylic polymer.
[0046] Example 3
[0047] Same as in Example 1, except that [2-oxo-2-[2-(2-oxoimidazolidine-1-yl)ethylamino]ethyl]2-methylprop-2-enoate was not added in the preparation of the acrylic polymer.
[0048] Example 4
[0049] Same as Example 1, except that lauryl acrylate is replaced with butyl acrylate in the preparation of the acrylic polymer.
[0050] Example 5
[0051] Same as in Example 1, except that octadecyl acrylate is replaced with ethyl acrylate in the preparation of the acrylic polymer.
[0052] Test Example 1
[0053] Sampling was performed on the coatings in the control example and examples according to GB / T12573-2008 "Sampling Method for Cement". After preparing the coatings, tensile strength and toughness tests were conducted on the coatings, referring to GB / T 16777-2008 "Test Method for Waterproof Coatings for Buildings" and GB / T 1732-2020 "Test Method for Impact Resistance of Paint Films". The coatings in the control example and examples were applied to the concrete slab in three coats, with each coat spaced 40 minutes apart. After application, the samples were cured at room temperature for 7 days. The tensile properties of the cured coatings were then tested. The same application method was used to apply the coatings in three coats to a tinplate sheet, followed by an impact strength test.
[0054] Table 1 Mechanical property tests of waterproof and anti-corrosion coatings for concrete
[0055] Compare with Example 1 50.1 7.8 8.52 Compare with Example 2 51.2 8.1 8.98 Example 1 58.8 10.5 11.23 Example 2 52.3 8.31 9.21 Example 3 52.7 8.47 9.35 Example 4 57.8 9.89 10.34 Example 5 58.2 10.1 10.89
[0056] The mechanical properties of the coating are closely related to the composition, adhesion, and density of the coating. As can be seen from the comparison between the comparative example and the example, the mechanical properties of the coating are significantly worse when the graphene oxide is not modified. This is because graphene oxide has good dispersibility in water, but poor dispersibility in the organic solvent system of the present invention, which makes it prone to agglomeration and thus affects the performance of the coating. In the comparative example 2, only modified graphene oxide was added without adding acrylate polymer to modify the epoxy resin. Therefore, the crosslinking degree is poor compared to Example 1. Epoxy resin itself has defects such as many pores and poor toughness. The acrylate polymer in Example 1 has a variety of active groups such as epoxy groups, amino groups, and long alkyl chains, which allows it to not only combine with epoxy resin groups during the curing process, but also react with the curing agent, thereby reducing the porosity of the coating surface and improving the crosslinking degree of the coating. Therefore, the coating is more dense, and the modified graphene oxide has high strength. Modification improves its dispersibility in the coating, mitigating the defect of poor dispersibility. Thus, the coating in Example 1 exhibits the best mechanical properties. In Examples 2-5, the raw materials in the acrylate polymer were reduced and replaced, respectively. It can be seen that each component is indispensable for the mechanical properties of the coating. A lack of raw materials affects the composition of active groups in the acrylate polymer, thereby affecting the porosity and density of the coating. In Examples 4-5, the replacement of raw materials reduced the composition of hydrophobic alkyl chains in the acrylate polymer, but its effect on mechanical properties was not significant; it likely primarily affected water absorption.
[0057] Test Example 2
[0058] The coating was prepared according to the method in Test Example 1. The cured coating was immersed in water, the container was sealed, and after immersion for 48 hours, the sample was taken out, the surface moisture was wiped off, and the mass of each group of samples after immersion was tested. The water absorption rate of the coating was calculated by the mass difference before and after immersion.
[0059] Table 2 Waterproofing Performance Tests of Waterproof and Anticorrosive Coatings for Concrete
[0060]
[0061]
[0062] A key indicator of the performance of waterproof coatings is their water absorption rate. Epoxy resin coatings typically absorb water for the following reasons: water dissolves into the epoxy resin matrix as water molecules, causing the epoxy system to absorb water; the epoxy resin structure contains numerous hydrophilic groups, such as hydroxyl groups, and amine groups in amine curing agents, which readily absorb moisture, leading to water absorption; the cured epoxy resin product is not a dense structure, containing many pores, which also absorb some moisture, increasing the system's water absorption rate. In this invention, the epoxy resin is modified to alter its cured structure, resulting in a large number of hydrophobic groups and reducing water absorption. Furthermore, modification of the epoxy resin's acrylate content improves its density and reduces its porosity, making it less susceptible to water penetration into the coating. Since coating density and porosity are positively correlated with water absorption, Example 1 exhibits a lower water absorption rate. Compared to Examples 4 and 5, Example 1 has more hydrophobic alkyl chains in the modified composite epoxy resin, resulting in poorer water absorption and better water resistance.
[0063] Test Example 3
[0064] The coating was prepared on a concrete slab according to the method in Test Example 1. A 10% sulfuric acid solution, a 20% sodium hydroxide solution, and a 3% sodium chloride solution were prepared. After curing, the coating was immersed in the acid, alkali, and salt solutions, respectively. When removed, the residual liquid on the surface of the coating was absorbed with filter paper. The sample was placed in an oven and dried to constant weight. The mass loss rate of the coating in each medium was calculated.
[0065] Table 3. Corrosion resistance test of waterproof and anti-corrosion coatings for concrete.
[0066]
[0067]
[0068] The corrosion resistance is directly related to the density, porosity, and water absorption of the coating. A denser coating with fewer pores is less susceptible to corrosion, while poor water absorption means the coating is less affected by external solutions. Example 1 exhibits the best density and water resistance, resulting in superior corrosion resistance. This is not only due to the presence of active epoxy groups in the coating, which have good compatibility with epoxy resin, but also because it reacts with the curing agent during curing to improve the epoxy coating's performance. The modified epoxy resin also has a larger relative molecular weight and longer molecular chains, making it easier to entangle with the epoxy resin during solvent evaporation, thus sealing micropores and microcracks generated during curing and effectively reducing the penetration path of corrosive media. The coating exhibits good hydrophobicity and adhesion, reducing water adsorption and preventing the penetration of corrosive media. Furthermore, the modified graphene oxide is well dispersed in the coating. The high strength and large aspect ratio of graphene not only improve the mechanical properties of the coating but also effectively increase the transport path of corrosive media, further enhancing corrosion resistance.
[0069] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.
Claims
1. A waterproof and anti-corrosion coating for concrete, characterized in that, The product comprises components A and B, in parts by weight. Component A includes: 10-25 parts of acrylate polymer, 75-100 parts of epoxy resin, 1-10 parts of modified graphene oxide, 0.5-3 parts of leveling agent, 0.5-3 parts of dispersant, 0.5-1 part of defoamer, and 20-50 parts of solvent; component B includes 10-40 parts of curing agent. The method for preparing the acrylate polymer includes the following steps: Methyl methacrylate, lauryl acrylate, octadecyl acrylate, glycidyl methacrylate, and [2-oxo-2-[2-(2-oxoimidazol-1-yl)ethylamino]ethyl]2-methylprop-2-enoate were mixed in a molar ratio of 2~5:1~4:1~3:0.5~2:0.5~2 and stirred until homogeneous to obtain mixture 1. Then, 0.5~2wt% of azobisisobutyronitrile of mixture 1 was added and stirred until homogeneous to obtain mixture 2. One-fifth of mixture 2 was mixed with an equal volume of ethyl acetate and 0.1~0.2wt% of dodecanethiol of mixture 2. The mixture was heated to 85~95℃ under an inert atmosphere and stirred to carry out polymerization. The remaining mixture 2 was then added in batches, and stirred for 10~30 min after each addition. After all the mixture was added, stirring was continued for 20~30 min to polymerize the product. The method for preparing the modified graphene oxide includes the following steps: 1,12-Diaminododecane was added to anhydrous ethanol and stirred to dissolve. Then, an equal volume of graphene oxide aqueous dispersion was added. The mass ratio of 1,12-diaminododecane to graphene oxide was 1:
1. The mixture was heated to 80-90°C and stirred for 6-10 hours. After cooling to room temperature, the mixture was centrifuged. The lower precipitate was washed with ethanol and dried to obtain the final product.
2. The waterproof and anti-corrosion coating for concrete as described in claim 1, characterized in that, The leveling agent is BYK-300; the dispersant is BYK-P104S.
3. The waterproof and anti-corrosion coating for concrete as described in claim 1, characterized in that, The defoamer is BYK-070.
4. The waterproof and anti-corrosion coating for concrete as described in claim 1, characterized in that, The solvent is one of acetone, ethyl acetate, and ethylene glycol butyl ether.
5. The waterproof and anti-corrosion coating for concrete as described in claim 1, characterized in that, The curing agent is one of ethylenediamine, diethylenetriamine, diethylaminopropylamine, or phenolic amine curing agents.
6. A method for preparing a waterproof and anti-corrosion coating for concrete as described in any one of claims 1 to 5, characterized in that, Includes the following steps: After mixing the acrylate polymer, epoxy resin, modified graphene oxide, leveling agent, dispersant, defoamer, and solvent according to the specified ratio, the mixture is stirred evenly to obtain component A. Component A is then mixed with component B and stirred evenly to obtain the final product.