Water-based concrete composite anticorrosive coating and preparation method thereof

Abstract

This invention discloses a water-based composite anti-corrosion coating for concrete and its preparation method, relating to the field of coatings. The invention utilizes a semi-continuous seed emulsion method, employing methyl methacrylate, butyl acrylate, acrylic acid, and the organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane (γ-MPS) to obtain a water-based organosilicon-modified acrylate emulsion as the film-forming substance. Then, hydrophobically modified nano-silica is composited as a dopant filler, and the water-based composite anti-corrosion coating for concrete is obtained through physical blending. The coating prepared by this invention uses a water-based emulsion as the film-forming substance, resulting in low organic matter emissions and strong environmental friendliness. Furthermore, the inclusion of hydrophobically modified nano-silica strengthens the coating structure, while the cross-linking structure between the organosilicon-modified acrylate polymers imparts a certain degree of toughness. This combination of rigidity and flexibility results in excellent mechanical properties, while the hydrophobic structure prevents water molecule penetration and corrosion, giving the coating superior anti-corrosion performance.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a water-based anti-corrosion coating for concrete and its preparation method. Background Technology

[0002] Existing highway bridges, concrete bridge decks, guardrails, and other structures in my country are often subjected to multiple factors during service, including freeze-thaw cycles, corrosion, alkali-aggregate reactions, steel reinforcement corrosion, and mechanical damage. Concrete structures often exhibit layered spalling, exposed aggregate, and loose, exposed reinforcement. Under stress corrosion, the surface layer may peel off, and in severe cases, it may expand and loosen. Some concrete structures may not show obvious external corrosion or deterioration, but their strength is significantly reduced, indicating severe damage. In highway networks and urban construction, the daily maintenance of many bridge concrete components is inadequate, posing a serious risk of durability failure.

[0003] Over the past few decades, various methods have been researched to provide durable concrete and address corrosion problems. Before corrosion damage occurs in concrete structures, applying a protective coating to the concrete surface is one of the most effective and economical ways to mitigate corrosion damage. The coating prevents corrosive substances from eroding the substrate, enhances the concrete's corrosion resistance, and improves its durability. Even after corrosion damage has occurred, protective coating treatment can still be applied in addition to conventional repair and reinforcement methods.

[0004] Traditional solvent-based anti-corrosion coatings use large amounts of organic solvents in their production. During application, solvent evaporation not only harms the environment but also affects human health. Therefore, water-based anti-corrosion coatings, which are low in toxicity and harmless, have become a hot research topic. Summary of the Invention

[0005] The purpose of this invention is to provide a water-based concrete anti-corrosion coating and its preparation method to solve the problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing a water-based concrete anti-corrosion coating, characterized by comprising the following preparation steps:

[0007] (1) Provide an emulsifier solution;

[0008] (2) Weigh out methyl methacrylate, butyl acrylate, acrylic acid, and organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion, mix them evenly, take a part of the mixture as seed monomer, and add it dropwise to the emulsifier solution obtained in step (1) to obtain a milky white seed emulsion.

[0009] (3) Weigh the pH buffer into a container, and under heating conditions, add the white emulsion obtained in step (2) and react until the solution changes from white to blue.

[0010] (4) Add the remaining mixture from step (2) and the initiator, heat, and obtain an aqueous organosilicon-modified acrylate emulsion;

[0011] (5) Weigh nano-silica, deionized water, anhydrous ethanol, ammonia, silane coupling agent KH-560 and tetraethyl orthosilicate into a container according to the proportion, heat and mix, then add hydrophobic long chain modifier, and react to obtain modified nano-silica gel.

[0012] (6) The modified nano-silica gel obtained in step (5) is washed, dried, and ground to obtain hydrophobic modified nano-silica particles;

[0013] (7) Add organosilicon-modified acrylate emulsion to a container, stir, add dispersant, wetting agent, and hydrophobic modified silica nanoparticles, stir evenly, and then add film-forming aid, thickener, leveling agent, pH adjuster, and mildew inhibitor in proportion, continue to disperse evenly, and obtain water-based concrete composite anti-corrosion coating. Further, the emulsifier in step (1) is 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate, and its mass ratio is 1~3% of the total mass of the four monomers in step (2).

[0014] Furthermore, in step (2), the ratio of methyl methacrylate, butyl acrylate, acrylic acid, and organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane is 8~12:10.5~12.5:1:1; the proportion of the seed monomer is 5%~15% of the total monomer mass.

[0015] Furthermore, the pH buffer in step (3) is sodium bicarbonate; the initiator in step (4) is ammonium persulfate, and its mass ratio is 0.3~1% of the total mass of the four monomers in step (2); the hydrophobic long-chain modifier in step (5) is octadecylamine.

[0016] Furthermore, in step (5), the nano-silica particles have a diameter of 5-15 nm and a specific surface area of ​​180-220 m². 2 / g.

[0017] Further, in step (7), the dispersant is 5040; the leveling agent is RM2020; the thickener is one or more of sodium polyacrylate and polyurethane alkali-swellable thickener; the wetting agent is one or two of CF-10, X-450 and TEGO Dispers 755W; the film-forming aid is alcohol ester dodecyl, the defoamer is one or two of BYK306 and F-2-2; the mildew inhibitor is one or two of benzoate and benzyl carbamate; and the pH adjuster is 2-amino-2-methyl-1-propanol pH adjuster.

[0018] Furthermore, a water-based concrete composite anti-corrosion coating is characterized in that, by composition, the water-based concrete composite anti-corrosion coating comprises: 80-120 parts of water-based organosilicon modified acrylic emulsion, 0.5-2.5 parts of hydrophobic modified nano-silica, 0.5-2 parts of dispersant, 0.1-1 parts of leveling agent, 0.5-3 parts of thickener, 0.1-0.3 parts each of wetting agent and defoamer, 1-2 parts of film-forming aid, 0.1-0.4 parts of mildew inhibitor, and 0.3-0.5 parts of pH adjuster; the coating is prepared by the method described above.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0020] This invention uses an aqueous organosilicon-modified acrylate emulsion as the film-forming material. When coated on a concrete surface, the polymer chains on the surface of the emulsion particles interact with each other, causing the particles to fuse and form a film. Under certain conditions, the carboxyl groups and other functional groups in the acrylate segments can undergo cross-linking reactions, further improving the strength and density of the film. Simultaneously, the organosilicon segments migrate to the surface of the film, giving the coating hydrophobicity. Due to the hydrophobic modification of the nano-silica particles, they have good compatibility with the organosilicon-modified acrylate polymer in the emulsion. During the drying and film-forming process of the coating, the nano-silica particles fill the pores of the polymer film, reducing the porosity of the coating and effectively preventing corrosive media. The organosilicon-modified acrylate polymer film and the nano-silica particles in the coating form a relatively dense protective layer, further improving the corrosion resistance of the coating.

[0021] Furthermore, nano-silica particles act as a reinforcing agent in the coating. When the coating is subjected to external forces, the nano-silica particles can bear some of the stress, improving the coating's hardness and wear resistance. Simultaneously, the cross-linking structure between the organosilicon-modified acrylate polymers also gives the coating a certain degree of toughness, enabling it to resist external forces to a certain extent without cracking. This combination of rigidity and flexibility allows the coating to adapt to deformations in concrete structures during use, preventing cracking and peeling. Moreover, the functional groups in the acrylate polymers can chemically bond and physically adsorb onto the concrete surface, improving the adhesion between the coating and the concrete substrate. This ensures the coating provides long-term, effective protection, preventing peeling and loss of protective function. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The test methods for various indicators of the water-based concrete composite anti-corrosion coating prepared in the following embodiments are as follows:

[0024] First, sand the concrete substrate surface clean to remove large protruding particles and stains, exposing a fresh and clean concrete surface. Then, clean the surface with a brush to remove any surface dust. Fill any cracks and level them with putty. Apply the composite coating to the concrete substrate using a top-down, even spraying method, starting with smaller areas and working up to larger areas. Apply three coats, ensuring each coat is surface dry before applying the next. After three coats, ensure there are no missed areas, runs, or uneven coating, and no material accumulation at corners.

[0025] Paint condition: Visual inspection

[0026] Drying time: JG / T 335-2011

[0027] Thickness: GB / T 13452.2-2008

[0028] Salt water resistance: GB / T 9274-1988

[0029] Adhesion: JT / T 695-2007

[0030] Chloride ion penetration resistance: GB / T 50082-2024

[0031] Mass gain rate: m2-m1 / m1*100% (m1 is the initial mass, m2 is the mass after 50 freeze-thaw cycles)

[0032] Compressive strength: GB / T 50081-2019

[0033] Compressive strength loss rate: P1-P2 / P1*100% (P1 is the initial compressive strength, and P2 is the compressive strength after 50 freeze-thaw cycles)

[0034] Example 1

[0035] (1) Weigh 0.58 parts of 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate according to the proportion, add deionized water to dissolve, stir evenly at 25℃ and 800r / min to completely dissolve and obtain an emulsifier solution with a solid content of 48.7%.

[0036] (2) Weigh out 10 parts of methyl methacrylate, 12.2 parts of butyl acrylate, 1 part of acrylic acid, and 1 part of organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion. After stirring evenly, take 10% of the total amount as seed monomer and add it dropwise to the emulsifier solution obtained in step (1). After pre-emulsification at 25℃ and 800r / min, a milky white seed emulsion is obtained.

[0037] (3) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0038] (4) Weigh 0.2 parts of sodium bicarbonate into a four-necked round-neck flask, add the milky white seed emulsion obtained in step (2), place the flask in a water bath and add a stirring rod, add the milky white seed emulsion obtained in the previous step into the flask and start stirring at a speed of 350 r / min, set the water bath temperature to 72℃, and stir while heating after placing the condenser; continue to keep the temperature and stir after the water temperature reaches 72℃ until the seed emulsion in the flask changes from white to blue.

[0039] (5) Adjust the water bath heating temperature to 75°C, continue to heat and stir, add the remaining monomer in step (2) and the ammonium persulfate solution obtained in step (3) to two constant pressure funnels respectively, and then drop them into the flask. After the titration is complete, raise the water bath temperature to 80°C and keep stirring for 1 hour. After the reaction is complete, filter and cool to obtain water-based organosilicon modified acrylate emulsion.

[0040] (6) Weigh out 3 parts of nano-silica, 40 parts of deionized water, 20 parts of anhydrous ethanol, 3 parts of ammonia, 3 parts of silane coupling agent KH-560, and 3 parts of tetraethyl orthosilicate according to the proportion. Place them in a round-bottom flask and put it in a water bath at 50°C for stirring until they are evenly mixed. Then raise the temperature to 60°C and add 1 part of saturated octadecylamine solution at once. Continue stirring at 60°C for 8 hours to obtain modified gel-like nano-silica.

[0041] (7) The modified nano silica gel obtained in step (6) was washed and centrifuged with anhydrous ethanol, dried at 80°C, and ground to obtain hydrophobic modified nano silica particles.

[0042] (8) Add 100 parts of organosilicon modified acrylate emulsion to a container, stir, add 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, 0.5 parts of hydrophobic modified silica nanoparticles, stir evenly, add 2 parts of alcohol ester twelve, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continue to disperse evenly, let stand for 2 hours, and obtain water-based concrete composite anti-corrosion coating.

[0043] Example 2

[0044] (1) Weigh 0.58 parts of 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate according to the proportion, add deionized water to dissolve, stir evenly at 25℃ and 800r / min to completely dissolve and obtain an emulsifier solution with a solid content of 48.7%.

[0045] (2) Weigh out 10 parts of methyl methacrylate, 12.2 parts of butyl acrylate, 1 part of acrylic acid, and 1 part of organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion. After stirring evenly, take 10% of the total amount as seed monomer and add it dropwise to the emulsifier solution obtained in step (1). After pre-emulsification at 25℃ and 800r / min, a milky white seed emulsion is obtained.

[0046] (3) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0047] (4) Weigh 0.2 parts of sodium bicarbonate into a four-necked round-neck flask, add the milky white seed emulsion obtained in step (2), place the flask in a water bath and add a stirring rod, add the milky white seed emulsion obtained in the previous step into the flask and start stirring at a speed of 350 r / min, set the water bath temperature to 72℃, and stir while heating after placing the condenser; continue to keep the temperature and stir after the water temperature reaches 72℃ until the seed emulsion in the flask changes from white to blue.

[0048] (5) Adjust the water bath heating temperature to 75°C, continue to heat and stir, add the remaining monomer in step (2) and the ammonium persulfate solution obtained in step (3) to two constant pressure funnels respectively, and then drop them into the flask. After the titration is complete, raise the water bath temperature to 80°C and keep stirring for 1 hour. After the reaction is complete, filter and cool to obtain water-based organosilicon modified acrylate emulsion.

[0049] (6) Weigh out 3 parts of nano-silica, 40 parts of deionized water, 20 parts of anhydrous ethanol, 3 parts of ammonia, 3 parts of silane coupling agent KH-560, and 3 parts of tetraethyl orthosilicate according to the proportion. Place them in a round-bottom flask and put it in a water bath at 50°C for stirring until they are evenly mixed. Then raise the temperature to 60°C and add 1 part of saturated octadecylamine solution at once. Continue stirring at 60°C for 8 hours to obtain modified gel-like nano-silica.

[0050] (7) The modified nano silica gel obtained in step (6) was washed and centrifuged with anhydrous ethanol, dried at 80°C, and ground to obtain hydrophobic modified nano silica particles.

[0051] (8) Add 100 parts of silicone-modified acrylate emulsion to a container, stir, add 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, 1.5 parts of hydrophobic modified silica nanoparticles, stir evenly, add 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continue to disperse evenly, let stand for 2 hours, and obtain water-based concrete composite anti-corrosion coating.

[0052] Example 3

[0053] (1) Weigh 0.58 parts of 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate according to the proportion, add deionized water to dissolve, stir evenly at 25℃ and 800r / min to completely dissolve and obtain an emulsifier solution with a solid content of 48.7%.

[0054] (2) Weigh out 10 parts of methyl methacrylate, 12.2 parts of butyl acrylate, 1 part of acrylic acid, and 1 part of organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion. After stirring evenly, take 10% of the total amount as seed monomer and add it dropwise to the emulsifier solution obtained in step (1). After pre-emulsification at 25℃ and 800r / min, a milky white seed emulsion is obtained.

[0055] (3) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0056] (4) Weigh 0.2 parts of sodium bicarbonate into a four-necked round-neck flask, add the milky white seed emulsion obtained in step (2), place the flask in a water bath and add a stirring rod, add the milky white seed emulsion obtained in the previous step into the flask and start stirring at a speed of 350 r / min, set the water bath temperature to 72℃, and stir while heating after placing the condenser; continue to keep the temperature and stir after the water temperature reaches 72℃ until the seed emulsion in the flask changes from white to blue.

[0057] (5) Adjust the water bath heating temperature to 75°C, continue to heat and stir, add the remaining monomer in step (2) and the ammonium persulfate solution obtained in step (3) to two constant pressure funnels respectively, and then drop them into the flask. After the titration is complete, raise the water bath temperature to 80°C and keep stirring for 1 hour. After the reaction is complete, filter and cool to obtain water-based organosilicon modified acrylate emulsion.

[0058] (6) Weigh out 3 parts of nano-silica, 40 parts of deionized water, 20 parts of anhydrous ethanol, 3 parts of ammonia, 3 parts of silane coupling agent KH-560, and 3 parts of tetraethyl orthosilicate according to the proportion. Place them in a round-bottom flask and put it in a water bath at 50°C for stirring until they are evenly mixed. Then raise the temperature to 60°C and add 1 part of saturated octadecylamine solution at once. Continue stirring at 60°C for 8 hours to obtain modified gel-like nano-silica.

[0059] (7) The modified nano silica gel obtained in step (5) was washed with anhydrous ethanol, centrifuged, dried at 80°C, and ground to obtain hydrophobic modified nano silica particles.

[0060] (8) Add 100 parts of silicone-modified acrylate emulsion to a container, stir, add 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, and 3 parts of hydrophobic modified silica nanoparticles. After stirring evenly, add 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate in proportion, continue to disperse evenly, and let stand for 2 hours to obtain water-based concrete composite anti-corrosion coating.

[0061] Example 4

[0062] (1) Weigh 0.58 parts of 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate according to the proportion, add deionized water to dissolve, stir evenly at 25℃ and 800r / min to completely dissolve and obtain an emulsifier solution with a solid content of 48.7%.

[0063] (2) Weigh out 15 parts of methyl methacrylate, 12.2 parts of butyl acrylate, 1 part of acrylic acid, and 1 part of organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion. After stirring evenly, take 10% of the total amount as seed monomer and add it dropwise to the emulsifier solution obtained in step (1). After pre-emulsification at 25℃ and 800r / min, a milky white seed emulsion is obtained.

[0064] (3) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0065] (4) Weigh 0.2 parts of sodium bicarbonate into a four-necked round-neck flask, add the milky white seed emulsion obtained in step (2), place the flask in a water bath and add a stirring rod, add the milky white seed emulsion obtained in the previous step into the flask and start stirring at a speed of 350 r / min, set the water bath temperature to 72℃, and stir while heating after placing the condenser; continue to keep the temperature and stir after the water temperature reaches 72℃ until the seed emulsion in the flask changes from white to blue.

[0066] (5) Adjust the water bath heating temperature to 75°C, continue to heat and stir, add the remaining monomer in step (2) and the ammonium persulfate solution obtained in step (3) to two constant pressure funnels respectively, and then drop them into the flask. After the titration is complete, raise the water bath temperature to 80°C and keep stirring for 1 hour. After the reaction is complete, filter and cool to obtain water-based organosilicon modified acrylate emulsion.

[0067] (6) Weigh out 3 parts of nano-silica, 40 parts of deionized water, 20 parts of anhydrous ethanol, 3 parts of ammonia, 3 parts of silane coupling agent KH-560, and 3 parts of tetraethyl orthosilicate according to the proportion. Place them in a round-bottom flask and put it in a water bath at 50°C for stirring until they are evenly mixed. Then raise the temperature to 60°C and add 1 part of saturated octadecylamine solution at once. Continue stirring at 60°C for 8 hours to obtain modified gel-like nano-silica.

[0068] (7) The modified nano silica gel obtained in step (5) was washed with anhydrous ethanol, centrifuged, dried at 80°C, and ground to obtain hydrophobic modified nano silica particles.

[0069] (8) Add 100 parts of silicone-modified acrylate emulsion to a container, stir, add 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, 1.5 parts of hydrophobic modified silica nanoparticles, stir evenly, add 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continue to disperse evenly, let stand for 2 hours, and obtain water-based concrete composite anti-corrosion coating.

[0070] Example 5

[0071] (1) Weigh 0.58 parts of 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate according to the proportion, add deionized water to dissolve, stir evenly at 25℃ and 800r / min to completely dissolve and obtain an emulsifier solution with a solid content of 48.7%.

[0072] (2) Weigh out 5 parts of methyl methacrylate, 12.2 parts of butyl acrylate, 1 part of acrylic acid, and 1 part of organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion. After stirring evenly, take 10% of the total amount as seed monomer and add it dropwise to the emulsifier solution obtained in step (1). After fully pre-emulsifying at 25℃ and 800r / min, a milky white seed emulsion is obtained.

[0073] (3) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0074] (4) Weigh 0.2 parts of sodium bicarbonate into a four-necked round-neck flask, add the milky white seed emulsion obtained in step (2), place the flask in a water bath and add a stirring rod, add the milky white seed emulsion obtained in the previous step into the flask and start stirring at a speed of 350 r / min, set the water bath temperature to 72℃, and stir while heating after placing the condenser; continue to keep the temperature and stir after the water temperature reaches 72℃ until the seed emulsion in the flask changes from white to blue.

[0075] (5) Adjust the water bath heating temperature to 75°C, continue to heat and stir, add the remaining monomer in step (2) and the ammonium persulfate solution obtained in step (3) to two constant pressure funnels respectively, and then drop them into the flask. After the titration is complete, raise the water bath temperature to 80°C and keep stirring for 1 hour. After the reaction is complete, filter and cool to obtain water-based organosilicon modified acrylate emulsion.

[0076] (6) Weigh out 3 parts of nano-silica, 40 parts of deionized water, 20 parts of anhydrous ethanol, 3 parts of ammonia, 3 parts of silane coupling agent KH-560, and 3 parts of tetraethyl orthosilicate according to the proportion. Place them in a round-bottom flask and put it in a water bath at 50°C for stirring until they are evenly mixed. Then raise the temperature to 60°C and add 1 part of saturated octadecylamine solution at once. Continue stirring at 60°C for 8 hours to obtain modified gel-like nano-silica.

[0077] (7) The modified nano silica gel obtained in step (5) was washed with anhydrous ethanol, centrifuged, dried at 80°C, and ground to obtain hydrophobic modified nano silica particles.

[0078] (8) Add 100 parts of silicone-modified acrylate emulsion to a container, stir, add 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, 1.5 parts of hydrophobic modified silica nanoparticles, stir evenly, add 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continue to disperse evenly, let stand for 2 hours, and obtain water-based concrete composite anti-corrosion coating.

[0079] Comparative Example 1

[0080] The difference between Comparative Example 1 and Example 2 is that steps (6) and (7) are deleted, and step (8) is changed to adding 100 parts of organosilicon modified acrylate emulsion to a container, stirring, adding 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, and 1.5 parts of unmodified silica nanoparticles. After stirring evenly, 2 parts of alcohol ester twelve, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate are added in proportion, and the mixture is further dispersed evenly and allowed to stand for 2 hours to obtain a water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0081] Comparative Example 2

[0082] The difference between Comparative Example 2 and Example 2 is that steps (6) and (7) are deleted, and step (8) is changed to adding 100 parts of silicone-modified acrylate emulsion to a container, stirring, adding 1 part of dispersant 5040 and 0.2 parts of wetting agent X-450, stirring evenly, and then adding 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol and 0.2 parts of benzoate according to the proportion, continuing to disperse evenly, and standing for 2 hours to obtain water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0083] Comparative Example 3

[0084] The difference between Comparative Example 3 and Example 2 is that steps (6) and (7) are deleted, and step (8) is changed to adding 100 parts of organosilicon modified acrylate emulsion to a container, stirring, adding 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, adding 0.025 parts of commercially available graphene oxide that is evenly dispersed, stirring evenly, adding 2 parts of alcohol ester dodecyl, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate in proportion, continuing to disperse evenly, and standing for 2 hours to obtain water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0085] Comparative Example 4

[0086] The difference between Comparative Example 4 and Example 2 is that steps (6) and (7) are deleted, and step (8) is changed to adding 100 parts of silicone-modified acrylate emulsion to a container, stirring, adding 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, adding 1.5 parts of commercially available nano titanium dioxide particles, stirring evenly, and then adding 2 parts of alcohol ester twelve, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continuing to disperse evenly, and standing for 2 hours to obtain water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0087] Comparative Example 5

[0088] The difference between Comparative Example 5 and Example 2 is that steps (6) and (7) are deleted, and step (8) is changed to adding 100 parts of silicone-modified acrylate emulsion to a container, stirring, adding 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, adding 1.5 parts of commercially available nano-calcium carbonate particles, stirring evenly, and then adding 2 parts of alcohol ester twelve, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continuing to disperse evenly, and standing for 2 hours to obtain water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0089] Comparative Example 6

[0090] The difference between Comparative Example 6 and Example 2 is that steps (1) to (5) are changed to:

[0091] (1) Weigh 11 parts of methyl methacrylate, 1 part of methacrylic acid, 15 parts of butyl acrylate and 3 parts of epoxy resin according to the proportion, stir evenly at 25℃ and 800r / min to obtain monomer mixture.

[0092] (2) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0093] (2) Weigh 4 parts of octylphenol polyoxyethylene ether-10, 0.5 parts of sodium dodecyl sulfate and 0.2 parts of sodium bicarbonate according to the proportion, mix them evenly, and place them in a round-bottom flask in a water bath at 55°C and stir for 30 min to make them evenly mixed. Control the dropping rate to add 20% of the total number of monomer mixed solutions dropwise using a constant pressure dropping funnel within 30 min. After the dropping is completed, raise the temperature of the reaction system to 70°C and add the ammonium persulfate solution obtained in step (2) and all the remaining monomer solutions. After all the materials are added, continue to raise the temperature to 80°C and keep the reaction at that temperature for 1 hour. After cooling to room temperature, filter and discharge the material to obtain epoxy acrylic emulsion; the remaining steps are the same as in Example 2.

[0094] Comparative Example 7

[0095] The difference between Comparative Example 7 and Example 2 is that steps (1) to (5) are changed to:

[0096] (1) Weigh 11 parts of methyl methacrylate, 1 part of methacrylic acid, and 15 parts of butyl acrylate according to the proportion. Stir at 25℃ and 800r / min until homogeneous to obtain a monomer mixture.

[0097] (2) Weigh 0.15 parts of ammonium persulfate according to the proportion and dissolve it completely in 100 times its weight of deionized water to obtain an ammonium persulfate solution;

[0098] (3) Mix 4 parts of octylphenol polyoxyethylene ether-10, 0.5 parts of sodium dodecyl sulfate, 40 parts of deionized water, and 0.2 parts of sodium bicarbonate evenly, and place them in a round-bottom flask in a water bath at 55°C and stir for 30 min to make them evenly mixed. Control the dropping rate to add 20% of the total number of monomer mixed solutions dropwise using a constant pressure dropping funnel within 30 min. After the dropping is completed, raise the temperature of the reaction system to 70°C and add the ammonium persulfate solution obtained in step (2), 4 parts of dodecyl fluoroheptyl methacrylate, and all the remaining monomer solutions. After all materials are added, continue to raise the temperature to 80°C and keep the reaction at that temperature for 1 hour. After cooling to room temperature, filter and discharge to obtain a fluorinated acrylic emulsion; the remaining steps are the same as in Example 2.

[0099] Comparative Example 8

[0100] The difference between Comparative Example 8 and Example 2 is that steps (1) to (5) are deleted, and step (8) is changed to: adding 100 parts of commercially available silicone acrylic emulsion to a container, stirring, adding 1 part of dispersant 5040, 0.2 parts of wetting agent X-450, and 1.5 parts of hydrophobic modified silica nanoparticles, stirring evenly, and then adding 2 parts of alcohol ester twelve, 1 part of sodium polyacrylate, 1 part of RM2020, 0.5 parts of 2-amino-2-methyl-1-propanol, and 0.2 parts of benzoate according to the proportion, continuing to disperse evenly, and standing for 2 hours to obtain water-based concrete composite anti-corrosion coating; the remaining steps are the same as in Example 2.

[0101] Example of effect

[0102] Table 1 below shows the performance analysis results of the waterborne concrete composite coatings of Examples 1 to 3 and Comparative Examples 1 to 8 of the present invention.

[0103] Table 1

[0104] Coating condition Drying time (h) Actual working time (h) Thickness (μm) Salt water resistance Adhesion (MPa) Resistance to chloride ion penetration (6h, C) Quality increase rate (%) Compressive strength loss rate (%) Example 1 No reunion 1.5 14 155 240 hours, no shedding 1.51 886.53 7.3 24.3 Example 2 No reunion 1.5 14 160 240 hours, no shedding 1.68 746.24 5.6 21.6 Example 3 No reunion 1.5 15 170 240 hours, no shedding 1.54 800.21 7.8 23.4 Example 4 No reunion 2 20 160 240h, foaming 1.39 903.6 9.87 24.36 Example 5 No reunion 1.5 15 160 240h, foaming 1.42 932.46 9.95 26.75 Comparative Example 1 Reunion 1.6 17 170 240 hours, no shedding 1.28 890.21 7.9 25.4 Comparative Example 2 No reunion 1.5 14 120 240h, foaming 1.36 1000.57 9.24 25.32 Comparative Example 3 Reunion 1.5 15 140 240 hours, no shedding 1.54 920.37 8.72 21.43 Comparative Example 4 No reunion 1.5 14 160 240 hours, no shedding 1.34 1050.27 8.03 22.79 Comparative Example 5 No reunion 1.5 14 160 240 hours, no shedding 1.46 1000.34 7.96 22.45 Comparative Example 6 No reunion 1.8 17 160 240 hours, no shedding 1.64 988.32 7.04 22.73 Comparative Example 7 No reunion 1.8 17 160 240 hours, no shedding 1.58 985.73 7.52 22.89 Comparative Example 8 No reunion 2 17 160 240 hours, no shedding 1.62 997.25 8.35 25.02

[0105] A comparison of the data from the examples and comparative examples reveals that this invention uses an aqueous organosilicon-modified acrylate emulsion as the film-forming material. When coated on a concrete surface, the polymer chains on the surface of the emulsion particles interact with each other, causing the particles to fuse and form a film. Under certain conditions, the carboxyl groups and other functional groups in the acrylate segments can undergo cross-linking reactions, further improving the strength and density of the film. Simultaneously, the organosilicon segments migrate to the surface of the film, giving the coating hydrophobicity. Due to the hydrophobic modification of the nano-silica particles, they have good compatibility with the organosilicon-modified acrylate polymer in the emulsion. During the coating drying process, the nano-silica particles fill the pores of the polymer film, reducing the porosity of the coating and effectively preventing corrosive media. The organosilicon-modified acrylate polymer film and the nano-silica particles in the coating form a relatively dense protective layer, further improving the corrosion resistance of the coating. Furthermore, the nano-silica particles play a reinforcing role in the coating; when the coating is subjected to external forces, the nano-silica particles can bear some of the stress, improving the hardness and wear resistance of the coating. Meanwhile, the cross-linking structure between the organosilicon-modified acrylate polymers also endows the coating with a certain degree of toughness, enabling it to resist external forces to a certain extent without cracking. This combination of rigidity and flexibility allows the coating to adapt to deformations in concrete structures during use, without easily cracking or peeling. Furthermore, the functional groups in the acrylate polymers can chemically bond and physically adsorb onto the concrete surface, improving the adhesion between the coating and the concrete substrate, ensuring the coating provides long-term effective protection and preventing peeling and loss of protective function. The coating prepared in this invention uses an aqueous emulsion as the film-forming substance, reducing organic emissions and making it highly environmentally friendly. Simultaneously, the inclusion of nanoparticles provides superior anti-corrosion performance.

[0106] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no designations in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a water-based concrete composite anti-corrosion coating, characterized in that, The preparation steps include the following: (1) Provide an emulsifier solution; (2) Weigh out methyl methacrylate, butyl acrylate, acrylic acid, and organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane according to the proportion, mix them evenly to obtain a mixture, take a portion of the mixture as seed monomer, and add it dropwise to the emulsifier solution obtained in step (1) to obtain a milky white seed emulsion; the ratio of methyl methacrylate, butyl acrylate, acrylic acid, and organosilicon monomer γ-methacryloyloxypropyltrimethoxysilane is 8~12:10.5~12.5:1:1; the proportion of seed monomer is 5%~15% of the total monomer mass; (3) Weigh the pH buffer into a container, and add the milky white seed emulsion obtained in step (2) under heating conditions. The reaction continues until the emulsion changes from white to blue. (4) Add the remaining mixture from step (2) and the initiator, heat, and obtain an aqueous organosilicon-modified acrylate emulsion; (5) Weigh nano-silica, deionized water, anhydrous ethanol, ammonia, silane coupling agent KH-560, and tetraethyl orthosilicate into a container according to the proportion, heat and mix, then add hydrophobic long-chain modifier, and react to obtain modified nano-silica gel; the hydrophobic long-chain modifier is octadecylamine; (6) The modified nano-silica gel obtained in step (5) is washed, dried, and ground to obtain hydrophobic modified nano-silica particles; (7) Add organosilicon-modified acrylate emulsion to a container, stir, add dispersant, wetting agent, hydrophobic modified nano-silica particles, stir evenly, add film-forming aid, thickener, leveling agent, pH adjuster and mildew inhibitor in proportion, continue to disperse evenly, and obtain water-based concrete composite anti-corrosion coating. The water-based concrete composite anti-corrosion coating comprises, by composition: 80-120 parts of water-based organosilicon modified acrylic emulsion, 0.5-2.5 parts of hydrophobic modified nano-silica particles, 0.5-2 parts of dispersant, 0.1-1 parts of leveling agent, 0.5-3 parts of thickener, 0.1-0.3 parts each of wetting agent and defoamer, 1-2 parts of film-forming aid, 0.1-0.4 parts of mildew inhibitor, and 0.3-0.5 parts of pH adjuster.

2. The preparation method of a water-based concrete composite anti-corrosion coating according to claim 1, characterized in that, The emulsifier in step (1) is 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate, and its mass is 1 to 3% of the total mass of the four monomers in step (2).

3. The preparation method of a water-based concrete composite anti-corrosion coating according to claim 1, characterized in that, In step (3), the pH buffer is sodium bicarbonate; in step (4), the initiator is ammonium persulfate, the mass of which is 0.3~1% of the total mass of the four monomers in step (2).

4. The preparation method of a water-based concrete composite anti-corrosion coating according to claim 1, characterized in that, Step (5) The nano-silica particles have a diameter of 5~15nm and a specific surface area of ​​180~220m². 2 / g.

5. The method for preparing a water-based concrete composite anti-corrosion coating according to claim 1, characterized in that, Step (7) The dispersant is 5040; the leveling agent is RM2020; the thickener is one or more of sodium polyacrylate and polyurethane alkali swelling thickener; the wetting agent is one or two of CF-10, X-450 and TEGO Dispers 755W; the film-forming aid is alcohol ester dodecyl; the defoamer is BYK306; the mildew inhibitor is one or two of benzoate and benzyl carbamate; the pH adjuster is 2-amino-2-methyl-1-propanol.

6. A water-based concrete composite anti-corrosion coating, characterized in that, The anti-corrosion coating is prepared by the preparation method according to any one of claims 1-5.