High-hardness scratch-resistant nano coating material and application thereof in floor repair

Abstract

The invention discloses a high-hardness scratch-resistant nano coating material and application thereof in floor repair, and belongs to the technical field of building materials. The nano coating material comprises a component A and a component B. The component A comprises the following raw materials in parts by mass: 35-50 parts of vinyl silane modified silicon dioxide sol, 10-20 parts of nano aluminum oxide aqueous dispersion, 5-15 parts of nano zirconium dioxide aqueous dispersion, 3-8 parts of a fluorine-containing silane coupling agent, 1-3 parts of sulfydryl grafted POSS-BA and the balance of deionized water, and the total mass part is 100 parts. The component B is prepared from the following raw materials in parts by mass: 40 to 60 parts of lithium silicate aqueous solution, 20 to 40 parts of potassium silicate aqueous solution and 1 to 5 parts of organic titanate. The coating material provided by the invention can be firmly combined with a base material through chemical bonds, and a formed coating has ultrahigh hardness and excellent wear resistance and is endowed with good scratch resistance and self-repairing performance.

Description

Technical Field

[0001] This invention belongs to the field of building materials technology, specifically relating to a high-hardness, scratch-resistant nano-coating material and its application in floor repair. Background Technology

[0002] Due to their unique textures and colors, natural marble floor tiles and marble ceramic tiles are widely used in high-end indoor and outdoor decoration. However, this type of stone flooring has certain drawbacks. First, due to its limited hardness, high-frequency use areas are prone to scratches and wear, resulting in a loss of luster. Second, surface stains are difficult to clean, as the micropores allow dirt (such as oil and pigments) to penetrate, making cleaning difficult. Furthermore, its corrosion resistance is poor; acidic or alkaline cleaners, rainwater, and pollutants can all cause surface corrosion and powdering. Currently, to maintain the aesthetics of this type of stone flooring, surface maintenance treatments are required, such as traditional waxing and crystallization. This maintenance requires frequent application, is costly, and some organic protective agents contain harmful substances such as VOCs and formaldehyde, which are detrimental to human health.

[0003] Therefore, there is an urgent need to develop a protective coating material for repairing stone floors that integrates high hardness, acid and alkali resistance, environmental friendliness (formaldehyde-free, low VOC), and easy cleaning, and is suitable for complex indoor and outdoor environments. Summary of the Invention

[0004] The purpose of this invention is to provide a high-hardness, scratch-resistant nano-coating material and its application in floor repair, which can solve the problem of easy scratching and wear of stone floors in the prior art.

[0005] The objective of this invention can be achieved through the following technical solutions: A high-hardness, scratch-resistant nano-coating material, comprising component A and component B; Component A, by mass parts, includes the following raw materials: Vinylsilane modified silica sol 35-50 parts, nano alumina aqueous dispersion 10-20 parts, nano zirconium dioxide aqueous dispersion 5-15 parts, fluorinated silane coupling agent 3-8 parts, mercapto-grafted POSS-BA 1-3 parts, balance deionized water, total mass parts 100. Component B, by mass parts, includes the following raw materials: 40-60 parts of lithium silicate aqueous solution, 20-40 parts of potassium silicate aqueous solution, and 1-5 parts of organotitanate ester; The thiol-grafted POSS-BA is prepared by grafting thiol groups onto the surface of boric acid-modified POSS via an esterification reaction.

[0006] Using the above technical solution, the coating material is a two-component system product. Component A, silica sol, provides basic hardness and adhesion, penetrating into the micropores of the stone to form a "rivet" effect, improving the coating's stain resistance. It works synergistically with other nano-inorganic materials in the raw materials to form a dense composite inorganic framework. The nanoparticle dispersion strengthening effect significantly enhances the coating's hardness and wear resistance. Nano-alumina greatly improves the coating's wear resistance, while nano-zirconia significantly enhances resistance to acid and alkali corrosion and wear resistance. The fluorosilane coupling agent provides excellent hydrophobicity and hydrophobicity. With its oil-free, easy-to-clean, and weather-resistant properties, POSS is an organic-inorganic hybrid material with good compatibility with other inorganic materials in the coating. It enhances the coating's hardness and abrasion resistance. Using POSS as a rigid node, the thiol groups on thiol-grafted POSS-BA can react and crosslink with the vinyl groups in vinyl silane-modified silica sol, introducing flexible segments between the rigid inorganic framework and the POSS cage. This adds chemical crosslinking to the inorganic crosslinking, strengthening the bonding force between materials and further enhancing the coating's hardness, thus imparting a certain degree of crack resistance. The thiol-grafted POSS-BA is dispersed at the nanoscale in the coating, ensuring its transparency and resulting in a high-gloss surface on the treated floor. Furthermore, the dynamic bonding of the borate esters on the thiol-grafted POSS-BA imparts repairability to the coating at room temperature.

[0007] Component B can act as an inorganic crosslinking enhancer. Under the catalysis of organic titanate, lithium silicate and potassium silicate in it can undergo rapid polycondensation reaction at room temperature, reacting with the silica sol in component A to form a three-dimensional network structure, promoting the curing of the coating. The inorganic network formed after the two components are cured can chemically bond with the stone, thereby providing extremely strong adhesion.

[0008] Furthermore, the silica content of the vinylsilane-modified silica sol is 15-20% by mass; The solid content of the nano-alumina aqueous dispersion is 10-20%; The solid content of the nano-zirconia aqueous dispersion is 10%-20%.

[0009] Furthermore, the mass fraction of the lithium silicate aqueous solution is 10-20%; The mass fraction of the potassium silicate aqueous solution is 10-20%.

[0010] Furthermore, the preparation method of the vinylsilane-modified silica sol is as follows: Vinylsilane was added to an aqueous ethanol solution at a mass concentration of 100-200 g / L and stirred to hydrolyze and form a transparent silane hydrolysate. An equal mass of deionized water was added to the silane hydrolysate, and the mixture was stirred until homogeneous. The mixture was then added to a silica sol, heated to 60-70°C, and stirred to react. After the reaction was completed, the mixture was concentrated by vacuum evaporation to control the silica mass content in the sol to 15-20%, thus obtaining a modified silica sol.

[0011] Furthermore, the silica sol has a silica content of 15-20% by mass and a silica particle size of 3-5 nm.

[0012] Furthermore, the vinylsilane is one of vinyltriethoxysilane, vinyltrimethoxysilane, and vinyltri(β-methoxyethoxy)silane.

[0013] Furthermore, the mass ratio of the vinylsilane to the silicon dioxide in the silica sol is 1-10:1.

[0014] Using the above technical solution, vinyl silane is hydrolyzed to form silanol. The silanol combines with the hydroxyl groups on the surface of silica in the silica sol, introducing vinyl groups on the surface of silica. The resulting modified silica sol can form chemical crosslinks with the mercapto-grafted POSS-BA in the coating, enhancing the degree of crosslinking between coating materials and increasing the hardness of the coating.

[0015] Furthermore, the fluorinated silane coupling agent is at least one of perfluorooctyltriethoxysilane and perfluorodecyltrimethoxysilane.

[0016] Furthermore, the preparation method of the thiol-grafted POSS-BA is as follows: S1. Add octa-aminophenyl-POSS, 4-formylphenylboronic acid, and sodium cyanoborohydride to methanol, sonicate for 20-50 min, stir the mixture at room temperature for 24-48 h, and remove methanol by rotary evaporation. S2. Wash with sodium bicarbonate solution and deionized water in sequence, and then dry under vacuum to obtain POSS-BA; S3. POSS-BA and 3-mercapto-1,2-propanediol were added to tetrahydrofuran and stirred to dissolve. Then magnesium sulfate and deionized water were added and stirred at room temperature for 12-24 hours. After filtration and concentration, the solvent was removed by rotary evaporation to obtain mercapto-grafted POSS-BA.

[0017] Furthermore, the mass ratio of the octa-aminophenyl-POSS to 4-formylphenylboronic acid is 1:2-6.

[0018] Furthermore, the mass ratio of sodium cyanoborohydride to 4-formylphenylboronic acid is 1-3:1.

[0019] Furthermore, the mass ratio of POSS-BA to 3-mercapto-1,2-propanediol is 1:0.1-0.5.

[0020] Furthermore, the magnesium sulfate is 5-10% of the mass of POSS-BA; The mass ratio of magnesium sulfate to deionized water is 1:0.02-0.05.

[0021] Using the above technical solution, under the reduction of sodium cyanoborohydride, octaaminophenyl-POSS undergoes a reducing amination reaction with 4-formylphenylboronic acid, introducing boric acid groups into the POSS structure. Then, the esterification reaction of the boric acid groups with 3-mercapto-1,2-propanediol forms a cyclic borate ester compound with thiol groups. The thiol groups enhance the cross-linking structure between POSS and silica sol in the coating, balancing the hardness and crack resistance of the coating. The dynamic bond structure of the borate ester allows the coating to self-repair after scratches at room temperature, resulting in better scratch resistance.

[0022] Furthermore, the organic titanate is at least one of tetrabutyl titanate and isopropyl titanate.

[0023] This invention also provides an application of a high-hardness, scratch-resistant nano-coating material in floor repair. The high-hardness, scratch-resistant nano-coating material described above is used to repair stone floors. The repair process includes the following steps: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3-4:1, and let it stand for 15-20 minutes after mixing. Step 2: Apply the cured coating material to the clean and dry stone floor surface using a high-pressure airless spraying device. After curing at room temperature for 48-72 hours, a coating will be formed.

[0024] The beneficial effects of this invention are: 1. The coating material of this invention is a two-component system. The coating material after mixing components A and B can react rapidly with the substrate surface and firmly bond with the substrate through chemical bonds. After film formation, a nano-organic silicon anti-corrosion and waterproof coating with dual physical and chemical protection is generated. The formed coating has extremely strong chemical resistance, ultra-high hardness, excellent wear resistance, and resistance to corrosion from chemicals such as acids, alkalis, salts, and oils. It is non-toxic, harmless, does not pollute the environment, and has a long service life.

[0025] 2. This invention modifies silica sol and adds mercapto-grafted POSS-BA, utilizing the reaction of vinyl groups and mercapto groups to build flexible chemical crosslinking chains between high-hardness inorganic nanoparticles in the coating material. This enhances the coating's hardness and imparts crack resistance. Furthermore, by utilizing the reversible generation and breakage characteristics of dynamic covalent borate esters, the coating acquires self-healing properties at room temperature.

[0026] 3. The present invention provides an inorganic framework structure through the silica sol in component A. The synergistic enhancement effect of nano-alumina and nano-zirconia gives the coating high hardness and greatly improves wear resistance. Nano-zirconia has excellent chemical inertness, and fluorinated silane provides a chemical barrier, enabling the coating to resist the corrosion of chemicals such as acids, alkalis and salts for a long time.

[0027] 4. The coating material of the present invention uses water as a dispersion medium, has no formaldehyde added, and has extremely low VOC content, meeting the most stringent environmental protection standards. The fluorinated silane gives the coating extremely low surface energy, exhibiting excellent hydrophobic and oleophobic properties, resisting stain adhesion, being extremely easy to clean, and having good UV resistance and weather resistance.

[0028] 5. The inorganic materials in the coating are similar to those in the stone, with strong permeability and high adhesion. At the same time, they can maintain the breathability of the stone and can be cured quickly at room temperature. There is no need for complicated post-treatment processes such as high-temperature baking or diamond grinding. Conventional methods can be used for construction. Detailed Implementation

[0029] 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.

[0030] Example 1

[0031] Preparation of vinylsilane-modified silica sol: Prepare an ethanol-water solution with a volume ratio of 6:4 for ethanol and water. Weigh out vinyltris(β-methoxyethoxy)silane and add it to the ethanol-water solution at a mass concentration of 160 g / L. Stir for 1 hour to hydrolyze and form a transparent silane hydrolysate. Add an equal mass of deionized water to the silane hydrolysate and stir until homogeneous. Then add it to a silica sol (silica mass content of 15%, silica particle size of 3-5 nm). The mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is 6:1. Heat to 65℃ and stir for 1.5 hours. After the reaction is complete, concentrate by vacuum evaporation to control the silica mass content in the sol to 15%, thus obtaining a modified silica sol.

[0032] Preparation of thiol-grafted POSS-BA: S1. Add octa-aminophenyl-POSS, 4-formylphenylboronic acid and sodium cyanoborohydride to methanol in a mass ratio of 1:4:4. The concentration of octa-aminophenyl-POSS in methanol is 3 g / L. Sonicate for 40 min, stir the mixture at room temperature for 24 h, and remove methanol by rotary evaporation.

[0033] S2. Washed sequentially with 5wt% sodium bicarbonate solution and deionized water, and dried under vacuum at 80℃ for 4h to obtain POSS-BA; S3. POSS-BA and 3-mercapto-1,2-propanediol were added to tetrahydrofuran at a mass ratio of 1:0.3, where the mass of tetrahydrofuran was 20 times that of POSS-BA. The mixture was stirred to dissolve, and then magnesium sulfate (7% of the mass of POSS-BA) was added. Deionized water was added simultaneously at a mass ratio of 1:0.03. The mixture was stirred at room temperature for 24 hours. After filtration and concentration, the solvent was removed by rotary evaporation to obtain mercapto-grafted POSS-BA.

[0034] Nano-coating materials: Component A: Prepare 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 2 parts of mercapto-grafted POSS-BA, and 23 parts of deionized water. Add all of these to a reaction vessel and stir until homogeneous to obtain Component A.

[0035] Component B: Prepare 50 parts of a 15% lithium silicate aqueous solution, 30 parts of a 15% potassium silicate aqueous solution, and 3 parts of tetrabutyl titanate. Add all of these to the reaction vessel and stir until homogeneous to obtain Component B.

[0036] Coating material application method: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3.5:1, and let it stand for 20 minutes to mature. Step 2: Apply the cured coating material to the clean and dry marble surface using a high-pressure airless spraying device. Allow it to surface dry for 45 minutes at room temperature (25°C), then allow it to fully dry for 12 hours. After complete curing, allow it to cure for 48 hours to form a coating with a thickness of 8 μm.

[0037] Example 2

[0038] The only difference from Example 1 is that, in preparing the vinylsilane-modified silica sol, the mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is adjusted to 1:1.

[0039] Example 3

[0040] The only difference from Example 1 is that, in preparing the vinylsilane-modified silica sol, the mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is adjusted to 10:1.

[0041] Example 4

[0042] The only difference from Example 1 is that, in preparing thiol-grafted POSS-BA, the mass ratio of octa-aminophenyl-POSS, 4-formylphenylboronic acid, and sodium cyanoborohydride was adjusted to 1:2:2.

[0043] Example 5

[0044] The only difference from Example 1 is that, in preparing thiol-grafted POSS-BA, the mass ratio of octa-aminophenyl-POSS, 4-formylphenylboronic acid, and sodium cyanoborohydride was adjusted to 1:6:6.

[0045] Example 6

[0046] The only difference from Example 1 is that, in preparing thiol-grafted POSS-BA, the mass ratio of POSS-BA to 3-mercapto-1,2-propanediol was adjusted to 1:0.1.

[0047] Example 7

[0048] The only difference from Example 1 is that, when preparing thiol-grafted POSS-BA, the mass ratio of POSS-BA to 3-mercapto-1,2-propanediol was adjusted to 1:0.5.

[0049] Example 8

[0050] The only difference from Example 1 is that the mass fraction of thiol-grafted POSS-BA in component A is increased to 3 parts, with the specific mass fraction ratio as follows: 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 3 parts of mercapto-grafted POSS-BA, and 22 parts of deionized water.

[0051] Example 9

[0052] The only difference from Example 1 is that the mass fraction of thiol-grafted POSS-BA in component A is reduced to 1 part, with the specific mass fraction ratio as follows: 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 1 part of mercapto-grafted POSS-BA, and 24 parts of deionized water.

[0053] Implementation 10

[0054] The only difference from Example 1 is that the mass fractions of each raw material in components A and B are different, and the specific mass fraction ratios are as follows: Component A: 35 parts of vinylsilane-modified silica sol, 20 parts of nano-alumina aqueous dispersion with a solid content of 15%, 15 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 8 parts of perfluorooctyltriethoxysilane, 2 parts of mercapto-grafted POSS-BA, and 20 parts of deionized water.

[0055] Component B: 40 parts of a 15% lithium silicate aqueous solution, 40 parts of a 15% potassium silicate aqueous solution, and 5 parts of tetrabutyl titanate.

[0056] Example 11

[0057] The only difference from Example 1 is that the mass fractions of each raw material in components A and B are different, and the specific mass fraction ratios are as follows: Component A: 50 parts of vinylsilane-modified silica sol, 10 parts of nano-alumina aqueous dispersion with a solid content of 15%, 5 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 3 parts of perfluorooctyltriethoxysilane, 2 parts of mercapto-grafted POSS-BA, and 30 parts of deionized water.

[0058] Component B: 60 parts of a 15% lithium silicate aqueous solution, 20 parts of a 15% potassium silicate aqueous solution, and 1 part of tetrabutyl titanate.

[0059] Comparative Example 1

[0060] The only difference from Example 1 is that the vinylsilane-modified silica sol in component A of the coating material is replaced by an equal mass of unmodified silica sol.

[0061] Preparation of thiol-grafted POSS-BA: S1. Add octa-aminophenyl-POSS, 4-formylphenylboronic acid and sodium cyanoborohydride to methanol in a mass ratio of 1:4:4. The concentration of octa-aminophenyl-POSS in methanol is 3 g / L. Sonicate for 40 min, stir the mixture at room temperature for 24 h, and remove methanol by rotary evaporation.

[0062] S2. Washed sequentially with 5wt% sodium bicarbonate solution and deionized water, and dried under vacuum at 80℃ for 4h to obtain POSS-BA; S3. POSS-BA and 3-mercapto-1,2-propanediol were added to tetrahydrofuran at a mass ratio of 1:0.3, where the mass of tetrahydrofuran was 20 times that of POSS-BA. The mixture was stirred to dissolve, and then magnesium sulfate (7% of the mass of POSS-BA) was added. Deionized water was added simultaneously at a mass ratio of 1:0.03. The mixture was stirred at room temperature for 24 hours. After filtration and concentration, the solvent was removed by rotary evaporation to obtain mercapto-grafted POSS-BA.

[0063] Nano-coating materials: Component A: Prepare 45 parts of silica sol (silica mass content of 15%, silica particle size of 3-5nm), 15 parts of nano alumina aqueous dispersion with a solid content of 15%, 10 parts of nano zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 2 parts of mercapto-grafted POSS-BA, and 23 parts of deionized water. Add all of these to the reaction vessel and stir evenly to obtain Component A.

[0064] Component B: Prepare 50 parts of a 15% lithium silicate aqueous solution, 30 parts of a 15% potassium silicate aqueous solution, and 3 parts of tetrabutyl titanate. Add all of these to the reaction vessel and stir until homogeneous to obtain Component B.

[0065] Coating material application method: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3.5:1, and let it stand for 20 minutes to mature. Step 2: Apply the cured coating material to the clean and dry marble surface using a high-pressure airless spraying device. Allow it to surface dry for 45 minutes at room temperature (25°C), then allow it to fully dry for 12 hours. After complete curing, allow it to cure for 48 hours to form a coating with a thickness of 8 μm.

[0066] Comparative Example 2

[0067] The only difference from Example 1 is that the coating material A component does not contain thiol-grafted POSS-BA.

[0068] Preparation of vinylsilane-modified silica sol: Prepare an ethanol-water solution with a volume ratio of 6:4 for ethanol and water. Weigh out vinyltris(β-methoxyethoxy)silane and add it to the ethanol-water solution at a mass concentration of 160 g / L. Stir for 1 hour to hydrolyze and form a transparent silane hydrolysate. Add an equal mass of deionized water to the silane hydrolysate and stir until homogeneous. Then add it to a silica sol (silica mass content of 15%, silica particle size of 3-5 nm). The mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is 6:1. Heat to 65℃ and stir for 1.5 hours. After the reaction is complete, concentrate by vacuum evaporation to control the silica mass content in the sol to 15%, thus obtaining a modified silica sol.

[0069] Nano-coating materials: Component A: Prepare 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, and 23 parts of deionized water. Add all of these to a reaction vessel and stir until homogeneous to obtain Component A.

[0070] Component B: Prepare 50 parts of a 15% lithium silicate aqueous solution, 30 parts of a 15% potassium silicate aqueous solution, and 3 parts of tetrabutyl titanate. Add all of these to the reaction vessel and stir until homogeneous to obtain Component B.

[0071] Coating material application method: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3.5:1, and let it stand for 20 minutes to mature. Step 2: Apply the cured coating material to the clean and dry marble surface using a high-pressure airless spraying device. Allow it to surface dry for 45 minutes at room temperature (25°C), then allow it to fully dry for 12 hours. After complete curing, allow it to cure for 48 hours to form a coating with a thickness of 8 μm.

[0072] Comparative Example 3

[0073] The only difference from Example 1 is that the reaction product of POSS-BA and 1,2-propanediol replaces the thiol group in POSS-BA grafting.

[0074] Preparation of vinylsilane-modified silica sol: Prepare an ethanol-water solution with a volume ratio of 6:4 for ethanol and water. Weigh out vinyltris(β-methoxyethoxy)silane and add it to the ethanol-water solution at a mass concentration of 160 g / L. Stir for 1 hour to hydrolyze and form a transparent silane hydrolysate. Add an equal mass of deionized water to the silane hydrolysate and stir until homogeneous. Then add it to a silica sol (silica mass content of 15%, silica particle size of 3-5 nm). The mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is 6:1. Heat to 65℃ and stir for 1.5 hours. After the reaction is complete, concentrate by vacuum evaporation to control the silica mass content in the sol to 15%, thus obtaining a modified silica sol.

[0075] Preparation of POSS-BA esterified products: S1. Add octa-aminophenyl-POSS, 4-formylphenylboronic acid and sodium cyanoborohydride to methanol in a mass ratio of 1:4:4. The concentration of octa-aminophenyl-POSS in methanol is 3 g / L. Sonicate for 40 min, stir the mixture at room temperature for 24 h, and remove methanol by rotary evaporation.

[0076] S2. Washed sequentially with 5wt% sodium bicarbonate solution and deionized water, and dried under vacuum at 80℃ for 4h to obtain POSS-BA; S3. POSS-BA and 1,2-propanediol were added to tetrahydrofuran at a mass ratio of 1:0.3, where the mass of tetrahydrofuran was 20 times that of POSS-BA. The mixture was stirred to dissolve, and then magnesium sulfate (7% of the mass of POSS-BA) was added. Deionized water was added simultaneously at a mass ratio of 1:0.03. The mixture was stirred at room temperature for 24 hours. After filtration and concentration, the solvent was removed by rotary evaporation to obtain the esterified product of POSS-BA.

[0077] Nano-coating materials: Component A: Prepare 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 2 parts of POSS-BA esterification product, and 23 parts of deionized water. Add all of these to the reaction vessel and stir evenly to obtain Component A.

[0078] Component B: Prepare 50 parts of a 15% lithium silicate aqueous solution, 30 parts of a 15% potassium silicate aqueous solution, and 3 parts of tetrabutyl titanate. Add all of these to the reaction vessel and stir until homogeneous to obtain Component B.

[0079] Coating material application method: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3.5:1, and let it stand for 20 minutes to mature. Step 2: Apply the cured coating material to the clean and dry marble surface using a high-pressure airless spraying device. Allow it to surface dry for 45 minutes at room temperature (25°C), then allow it to fully dry for 12 hours. After complete curing, allow it to cure for 48 hours to form a coating with a thickness of 8 μm.

[0080] Comparative Example 4

[0081] The only difference from Example 1 is that the mercapto-grafted POSS-BA in component A of the coating material is replaced by an equal amount of octa-aminophenyl-POSS.

[0082] Preparation of vinylsilane-modified silica sol: Prepare an ethanol-water solution with a volume ratio of 6:4 for ethanol and water. Weigh out vinyltris(β-methoxyethoxy)silane and add it to the ethanol-water solution at a mass concentration of 160 g / L. Stir for 1 hour to hydrolyze and form a transparent silane hydrolysate. Add an equal mass of deionized water to the silane hydrolysate and stir until homogeneous. Then add it to a silica sol (silica mass content of 15%, silica particle size of 3-5 nm). The mass ratio of vinyltris(β-methoxyethoxy)silane to silica in the silica sol is 6:1. Heat to 65℃ and stir for 1.5 hours. After the reaction is complete, concentrate by vacuum evaporation to control the silica mass content in the sol to 15%, thus obtaining a modified silica sol.

[0083] Nano-coating materials: Component A: Prepare 45 parts of vinylsilane-modified silica sol, 15 parts of nano-alumina aqueous dispersion with a solid content of 15%, 10 parts of nano-zirconium dioxide aqueous dispersion with a solid content of 15%, 5 parts of perfluorooctyltriethoxysilane, 2 parts of octa-aminophenyl-POSS, and 23 parts of deionized water. Add all of these to a reaction vessel and stir until homogeneous to obtain Component A.

[0084] Component B: Prepare 50 parts of a 15% lithium silicate aqueous solution, 30 parts of a 15% potassium silicate aqueous solution, and 3 parts of tetrabutyl titanate. Add all of these to the reaction vessel and stir until homogeneous to obtain Component B.

[0085] Coating material application method: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3.5:1, and let it stand for 20 minutes to mature. Step 2: Apply the cured coating material to the clean and dry marble surface using a high-pressure airless spraying device. Allow it to surface dry for 45 minutes at room temperature (25°C), then allow it to fully dry for 12 hours. After complete curing, allow it to cure for 48 hours to form a coating with a thickness of 8 μm.

[0086] The coatings formed from the coating materials of Examples 1-11 and Comparative Examples 1-4 were subjected to performance tests, and the results are shown in Table 1.

[0087] The reference standard for pencil hardness testing is GB / T 6739-2022.

[0088] The abrasion resistance test reference standard is GB / T 1768-2006, 750g / 500r.

[0089] The reference standard for VOC content testing is GB 38468-2019.

[0090] Reference standard for testing free formaldehyde content: GB 18582-2020.

[0091] Contact angle: The water contact angle of the coating was measured using the static drop method.

[0092] Adhesion: The adhesion of the coating was tested using the cross-cut test, referring to standard GB / T 9286-2021.

[0093] Self-healing performance: Micro-scratches (ten micrometers wide) were created on the coating surface using a standard scratch instrument, and the changes in scratch width were observed using an optical microscope. The time for the scratches to disappear at room temperature was also observed.

[0094] Table 1

[0095] As shown in Table 1, among Examples 1, 2, 3, and Comparative Example 1, the coating formed by the coating material in Example 1 has the highest hardness and best wear resistance. Modification of the silica sol with vinylsilane allows it to better form a cross-linking network with the mercapto-grafted POSS-BA, improving the coating's hardness and scratch resistance. In Example 3, when the amount of vinylsilane is higher, the compatibility of the silica sol with other inorganic materials decreases, and the wear resistance is slightly lower than in Example 1. The results of Examples 1 and Comparative Examples 2-4 show that the borate ester bonds formed by boric acid groups can promote coating repair. In Comparative Example 3, when the boric acid groups in POSS-BA form an ester with propylene glycol, it can impart certain self-healing properties to the coating. However, due to the lack of mercapto grafting, the degree of cross-linking with the silica sol is weakened, and the coating's repair performance is not as good as in Example 1.

[0096] The coating formed in this invention was tested for acid and alkali resistance according to the standard GB / T 9274-1988. The acid resistance test was performed by immersing the coating in a 10wt% H2SO4 solution for 24 hours, and the alkali resistance test was performed by immersing the coating in a 10wt% NaOH solution for 24 hours. After removing the acid and alkali solutions, the coating showed no change and no loss of gloss, indicating that it has good acid and alkali resistance.

[0097] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0098] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-hardness, scratch-resistant nano-coating material, characterized in that, It includes component A and component B; component A, by mass parts, includes the following raw materials: Vinylsilane modified silica sol 35-50 parts, nano alumina aqueous dispersion 10-20 parts, nano zirconium dioxide aqueous dispersion 5-15 parts, fluorinated silane coupling agent 3-8 parts, mercapto-grafted POSS-BA 1-3 parts, balance deionized water, total mass parts 100. Component B, by mass parts, includes the following raw materials: 40-60 parts of lithium silicate aqueous solution, 20-40 parts of potassium silicate aqueous solution, and 1-5 parts of organotitanate ester; The thiol-grafted POSS-BA is prepared by grafting thiol groups onto the surface of boric acid-modified POSS via an esterification reaction.

2. The high-hardness, scratch-resistant nano-coating material according to claim 1, characterized in that, The vinylsilane-modified silica sol has a silica content of 15-20% by mass; the nano-alumina aqueous dispersion has a solid content of 10-20%; the nano-zirconium dioxide aqueous dispersion has a solid content of 10%-20%; the lithium silicate aqueous solution has a mass fraction of 10-20%; and the potassium silicate aqueous solution has a mass fraction of 10-20%.

3. The high-hardness, scratch-resistant nano-coating material according to claim 1, characterized in that, The method for preparing the vinylsilane-modified silica sol is as follows: Vinylsilane was added to an aqueous ethanol solution at a mass concentration of 100-200 g / L and stirred to hydrolyze and form a transparent silane hydrolysate. An equal mass of deionized water was added to the silane hydrolysate, and the mixture was stirred until homogeneous. The mixture was then added to a silica sol, heated to 60-70°C, and stirred to react. After the reaction was completed, the mixture was concentrated by vacuum evaporation to control the silica mass content in the sol to 15-20%, thus obtaining a modified silica sol.

4. The high-hardness, scratch-resistant nano-coating material according to claim 3, characterized in that, The silica sol has a silica content of 15-20% by mass and a silica particle size of 3-5 nm.

5. The high-hardness, scratch-resistant nano-coating material according to claim 3, characterized in that, The vinylsilane is one of vinyltriethoxysilane, vinyltrimethoxysilane, and vinyltri(β-methoxyethoxy)silane; the mass ratio of the vinylsilane to the silica in the silica sol is 1-10:

1.

6. The high-hardness, scratch-resistant nano-coating material according to claim 1, characterized in that, The fluorinated silane coupling agent is at least one of perfluorooctyltriethoxysilane and perfluorodecyltrimethoxysilane.

7. The high-hardness, scratch-resistant nano-coating material according to claim 1, characterized in that, The method for preparing the thiol-grafted POSS-BA is as follows: S1. Add octa-aminophenyl-POSS, 4-formylphenylboronic acid, and sodium cyanoborohydride to methanol, sonicate for 20-50 min, stir the mixture at room temperature for 24-48 h, and remove methanol by rotary evaporation. S2. Wash with sodium bicarbonate solution and deionized water in sequence, and then dry under vacuum to obtain POSS-BA; S3. POSS-BA and 3-mercapto-1,2-propanediol were added to tetrahydrofuran and stirred to dissolve. Then magnesium sulfate and deionized water were added and stirred at room temperature for 12-24 hours. After filtration and concentration, the solvent was removed by rotary evaporation to obtain mercapto-grafted POSS-BA.

8. The high-hardness, scratch-resistant nano-coating material according to claim 7, characterized in that, The mass ratio of the octa-aminophenyl-POSS to 4-formylphenylboronic acid is 1:2-6; The mass ratio of sodium cyanoborohydride to 4-formylphenylboronic acid is 1-3:

1.

9. The high-hardness, scratch-resistant nano-coating material according to claim 7, characterized in that, The mass ratio of POSS-BA to 3-mercapto-1,2-propanediol is 1:0.1-0.

5.

10. The application of a high-hardness, scratch-resistant nano-coating material in floor repair, characterized in that, The stone floor is repaired using the high-hardness, scratch-resistant nano-coating material as described in any one of claims 1-9, the repair process comprising the following steps: Step 1: Mix component A and component B of the high-hardness anti-scratch nano-coating material at a mass ratio of 3-4:1, and let it stand for 15-20 minutes after mixing. Step 2: Apply the cured coating material to the clean and dry stone floor surface using a high-pressure airless spraying device. After curing at room temperature for 48-72 hours, a coating will be formed.

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