Anti-falling stone-like paint and construction process thereof

Abstract

The invention relates to the technical field of building decoration materials, in particular to anti-falling stone-like paint and a construction technology thereof. The construction process comprises the following steps: sequentially spraying and scraping anti-crack mortar on a wall base layer to form a leveling layer and a modeling layer; when the modeling layer is initially solidified and not dried, a wet reinforcing agent is immediately sprayed on the wet surface of the modeling layer to form a reinforcing agent layer; and then maintenance and polishing are conducted, and alkali-resistant seal primer, stone-like paint color points and finish-coat paint are sequentially coated. The inorganic aggregate contains an interface enhanced composite modifier, and is prepared by carrying out graft copolymerization on alkenyl polyurethane, a silane modified silicon dioxide compound and a mixture containing 2-acrylamido-2-methylpropanesulfonic acid, methyl methacrylate, butyl acrylate and a functional monomer. Through the synergistic effect of a unique process and raw materials, the technical problems that a traditional stone-like paint system is poor in interlayer adhesive force and prone to cracking, hollowing and falling off are fundamentally solved, and the bonding strength, crack resistance and durability of a coating are improved.

Description

Technical Field

[0001] This invention relates to the field of building decoration materials technology, specifically to a stone-like paint that prevents peeling and its construction process. Background Technology

[0002] Currently, the widely used exterior wall imitation marble (water-based multicolor) coating system in engineering projects generally follows this process: after leveling and plastering the base layer, a putty layer is first applied for leveling and priming, followed by a sealing primer, a multicolor intermediate coat, and finally, a water-based multicolor dot spray. From early water-based coatings and multicolor intermediate coats to later water-based sand coatings and multicolor dots, although the decorative effect has gradually approached that of dry-hanging stone, in many actual projects, quality problems such as peeling, cracking, bulging, and even complete detachment still frequently occur. This is especially prominent on exterior walls with large temperature variations, fluctuating base quality, or long-term exposure to rain and freeze-thaw cycles, seriously affecting the safety and durability of the facade.

[0003] Analysis of the failure mechanism of traditional stone-like coating systems reveals several weaknesses in their construction process: First, the quality of putty, used for leveling and priming the base layer, is often overlooked. Putty is cement-based and relatively rigid; improper mixing or insufficient curing can easily lead to problems such as powdering, peeling, cracking, and efflorescence, creating potential problems for subsequent coatings. Second, traditional stone-like paints use an emulsion-based organic intermediate coat, while putty is a cement-based inorganic system. The different material systems result in poor interlayer adhesion and a thinner intermediate coat film. When the putty is not strong enough, phenomena such as "masking tape peeling off easily," peeling, and flaking often occur. Third, ordinary stone-like paint intermediate coats are mostly flat and lack texture. The smooth surface leads to insufficient adhesion of colored dots, making thick sprays prone to dripping, cracking at corners, and flaking after exposure to rain or freezing. To achieve sufficient three-dimensionality and fullness, the amount of colored dots often needs to exceed 2.5%. The cost per kilogram of paint is high, resulting in high costs, long construction periods, and slow drying. Fourth, the overall film thickness of the stone-like paint system is relatively thin, making it weak in terms of impact and damage resistance. Once a local area is damaged, the putty layer with significant differences in color and performance is exposed, which not only affects the appearance but is also difficult to repair due to the large difference between the intermediate coat and the putty system. After long-term rainwater infiltration, the damaged area is prone to peeling, cracking, and further detachment.

[0004] To address the aforementioned issues, while the industry has attempted to improve system stability through methods such as increasing putty grade, thickening intermediate coats, using modified emulsions, or layering multiple primer coats and interface agents on the colored dot layer, the overall approach remains focused on patching up existing processes. It fails to systematically optimize the system from the perspectives of the crack resistance, density, and interlayer interface synergy of the thick-coating base material itself. Current technology lacks a robust, dense, flexible, and highly adhesive inorganic aggregate layer system that can form between the base layer and the finish, replacing traditional putty and flat intermediate coats while providing a solid and reliable support and long-term anti-detachment guarantee for water-based multi-colored stone-like finishes. Therefore, there is an urgent need to propose a new stone-like coating system and construction process that simultaneously solves long-standing problems such as cracking, hollowing, peeling, and detachment from both the material system and interface structure perspectives. Summary of the Invention

[0005] This invention aims to solve the problems of poor interlayer adhesion, easy cracking and peeling, poor texture and high cost of existing stone-like paint systems. It provides a stone-like paint with anti-peeling properties and its construction process, which improves the coating's bonding strength, crack resistance and durability by replacing traditional putty and intermediate coating with inorganic aggregates.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A process for applying a stone-like paint that prevents peeling includes the following steps:

[0008] Step 1: Apply crack-resistant mortar to the wall base layer to form a leveling layer;

[0009] Step 2: Mark the grid lines on the dry leveling layer;

[0010] Step 3: Spray inorganic aggregate slurry onto the leveled layer that has been divided into sections to form a shaping layer. The shaping layer is composed of inorganic aggregate slurry containing an interface-reinforcing composite modifier.

[0011] Step 4: While the molding layer is initially set but not completely dry, immediately spray a wet-spray reinforcing agent onto its wet surface to form a reinforcing agent layer;

[0012] Step 5: Curing and polishing the molding layer and reinforcing agent layer;

[0013] Step 6: Apply alkali-resistant sealing primer, imitation stone paint dots, and topcoat in sequence.

[0014] Preferably, the application process of the anti-peeling faux stone paint includes the following steps:

[0015] Step 1: Base treatment: Inspect the concrete wall to be constructed to ensure that there are no hollow areas, no oil stains, and no loose dust. Repair and level any uneven areas with cement mortar.

[0016] Step 2, leveling with crack-resistant mortar: Mix the crack-resistant mortar dry powder with water at a mass ratio of 100:(25-30), stir at a speed of 400-800 rpm for 3-8 minutes, let it stand and mature for 3-8 minutes, then stir again before use, until a uniform crack-resistant mortar clinker without dry powder particles is formed; use a trowel to scrape and level the base surface, with a total thickness of about 2-6 mm.

[0017] Step 3: Marking the grid lines: According to the design drawings, use ink lines to mark the grid lines on the leveled and dried inorganic aggregate layer to determine the position and width of the imitation stone grid lines.

[0018] Step 4: Add water to the inorganic aggregate dry powder and stir it into a slurry in the same way as in Step 2. On the wall surface with the marked grid lines, use a special spray gun with a nozzle diameter of 4-6mm to spray the design, with a spraying pressure of 0.5-1MPa and a design layer thickness of 1.2-2.6mm.

[0019] Step 5: Application of wet-sprayed reinforcing agent: After the inorganic aggregate is molded, while it is still damp after initial setting, apply the wet-sprayed reinforcing agent evenly to its surface. The application rate should be controlled at 0.12-0.2 kg / m². 2 The spraying pressure is 0.1-0.5MPa, the spraying distance is 25-36cm, and the coating is applied evenly in a cross pattern to form a uniform film of reinforcing agent on the surface. After spraying the reinforcing agent, let it stand for 12-48 hours to allow the inorganic aggregate layer and reinforcing agent layer to harden fully.

[0020] Step 6, Grinding and Curing: Use 200-300 grit sandpaper to lightly grind the surface of the inorganic aggregate layer to remove loose sand and sharp protrusions. After grinding, remove surface dust and continue natural curing for 24-72 hours.

[0021] Step 7: Application of Alkali-Resistant Sealing Primer: Apply one coat of alkali-resistant sealing primer evenly to the dry inorganic aggregate layer using a roller, with a coverage rate of 0.10-0.16 kg / m². 2 Allow to air dry naturally for 2-8 hours;

[0022] Step 8: Application of Stone-like Paint Dots: After the alkali-resistant sealing primer has dried, use a stone-like paint spray gun with a nozzle diameter of 2-5mm and an air pressure of 0.2-0.8MPa to spray one coat of water-based sand-textured stone-like paint dots using a cross-spraying method. After drying, spray another coat of water-based sand-textured stone-like paint dots. The dosage for each dot is 1.0kg / m². 2 After the imitation stone paint dot layer dries for 12-48 hours;

[0023] Step Nine: Topcoat Application: After the faux stone paint speckle layer is completely dry, apply one coat of fluorocarbon topcoat by roller, with a coverage rate of 0.08-0.16 kg / m².2 Topcoat paint can give the coating excellent stain resistance, water resistance and weather resistance, and unify the coating gloss, thereby improving the overall decorative effect and service life.

[0024] While a single cement-based thick aggregate coating can improve film thickness and resistance to damage, it still suffers from inherent defects such as excessive rigidity, insufficient crack resistance, and susceptibility to fatigue failure at the interlayer interface. This invention addresses this by incorporating a polymer modifier with a network structure into the inorganic aggregate formulation. This allows the thick coating to maintain high compressive strength while achieving good flexibility and interlayer adhesion. Furthermore, it densifies the pore structure at the microscopic level, preventing moisture intrusion, thereby significantly improving the crack resistance and interlayer adhesion of the thick inorganic aggregate coating. Under long-term thermal cycling and wet-drying cycling conditions, it effectively reduces the risk of delamination, peeling, and detachment, achieving structural stability and durability for the anti-detachment faux stone paint system.

[0025] The inorganic aggregate powder, by weight, comprises the following components:

[0026] 20-40 parts of silicate cement;

[0027] 32-50 parts of quartz sand;

[0028] 10-15 parts calcium carbonate;

[0029] 2-8 parts of redispersible latex powder;

[0030] 5-10 parts of interface-enhancing composite modifier.

[0031] Preferably, the inorganic aggregate dry powder in the stone-like paint is composed of the following raw materials in parts by weight: 20-40 parts by weight of silicate cement, 32-50 parts by weight of quartz sand, 48-18 parts by weight of calcium carbonate, 2-8 parts by weight of redispersible latex powder, 0.1-1 parts by weight of hydroxypropyl methylcellulose ether, 2-4 parts by weight of iron oxide red pigment, 6-10 parts by weight of interface-enhancing composite modifier, 0.05-0.3 parts by weight of defoamer, 0.2-0.6 parts by weight of film-forming aid, and 0.5-2 parts by weight of water-retaining agent.

[0032] Preferably, the defoamer is any one of mineral oil-based defoamers, silicone defoamers, and polyether defoamers.

[0033] Preferably, the film-forming aid is any one of ethylene glycol, propylene glycol, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol butyl ether, propylene glycol phenyl ether, and dodecyl alcohol ester.

[0034] Preferably, the water-retaining agent is any one of maltodextrin, water-soluble starch, sepiolite, calcium chloride, magnesium chloride, sodium humate, sodium polyacrylate, hydroxypropyl methylcellulose, and polyacrylamide.

[0035] The preparation method of the interface-enhancing composite modifier includes the following steps:

[0036] (1) React polyurethane with glycidyl acrylate to obtain alkenyl polyurethane;

[0037] (2) Reaction of silica and nano-montmorillonite with a silane coupling agent containing an active functional group yields a silane-modified silica composite; the active functional group includes at least one of amino, hydroxyl and double bond;

[0038] (3) The alkenyl polyurethane obtained in step (1), the silane-modified silica composite obtained in step (2), and a monomer mixture including 2-acrylamido-2-methylpropanesulfonic acid, functional monomers, methyl methacrylate and butyl acrylate are subjected to graft copolymerization in the presence of an initiator to obtain the interface-enhancing composite modifier.

[0039] This invention introduces an interface-reinforcing composite modifier into inorganic aggregate dry powder. The polyurethane soft segment provides high elongation and elasticity, while the acrylic hard segment and inorganic particles provide strength and stiffness. The two form an interwoven soft and hard network structure, which enables the thick coating to maintain high compressive strength and surface hardness while possessing significant flexibility and stress buffering capacity. This effectively reduces stress concentration caused by drying shrinkage, temperature difference and external force, significantly improves the crack resistance of the thick inorganic aggregate layer, and avoids the problem of inevitable cracking in thick coatings.

[0040] Secondly, polar functional groups such as hydroxyl, amide, and sulfonic acid groups are introduced into the interface-reinforcing composite modifier. Through a silane coupling agent, these groups interact chemically and physically with cement hydration products and aggregate surfaces, forming a continuous interface reinforcement layer in situ between the concrete substrate and the thick inorganic aggregate layer. This interface reinforcement layer can penetrate into the micropores of the substrate and solidify into a film on the pore walls, significantly improving the adhesion and bonding of the thick coating to the substrate. This transforms the damage from interfacial peeling to damage within the substrate or coating itself, fundamentally reducing the risk of hollowing, peeling, and complete detachment. Simultaneously, it provides a stable and reliable supporting interface for the upper faux stone paint and colored dot layers.

[0041] Finally, the inorganic particles such as nano-silica and montmorillonite in the composite modifier fill and refine the capillary structure, and in conjunction with polyurethane / acrylic film formation, significantly improve the density and impermeability of the thick coating, block the migration of moisture and corrosive media within the coating, and mitigate volume changes and interfacial fatigue failure caused by freeze-thaw cycles and wet-dry cycles. The modified inorganic aggregate thick coating possesses high strength, high toughness, high adhesion, and high density, and forms a composite system with gradual changes in mechanical properties and synergistic deformation with the subsequent wet-sprayed reinforcing agent layer, faux stone paint dot layer, and topcoat. This maintains structural stability under long-term thermal and wet-dry cycles, significantly improving the overall durability of the anti-peeling faux stone paint system and thus extending its service life.

[0042] Preferably, the interface-enhancing composite modifier is a composite polyurethane material, and the preparation method of the composite polyurethane material is as follows:

[0043] (1) Under nitrogen protection, 80-140 parts by weight of polyurethane were dissolved in 300-600 parts by weight of tetrahydrofuran and stirred to obtain a polyurethane solution; 5-10 parts by weight of glycidyl acrylate were added and reacted at 60-80℃ and 300-600rpm for 2-6h, centrifuged, distilled under reduced pressure, and dried under vacuum to obtain alkenylated polyurethane.

[0044] (2) Mix 5-12 parts by weight of silica, 1-4 parts by weight of nano-montmorillonite and 200-500 parts by weight of 50-70 wt% ethanol aqueous solution and sonicate. Add 2-5 parts by weight of silane coupling agent, adjust the pH to 4, and react at 70-85℃ and 400-700 rpm for 2-8 hours. Filter, wash and vacuum dry to obtain silane-modified silica composite. The silane coupling agent is a silane coupling agent containing amino, hydroxyl and double bonds.

[0045] (3) 20-30 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 8-16 parts by weight of methyl methacrylate, 3-8 parts by weight of functional monomer, 10-20 parts by weight of butyl acrylate, and 8-12 parts by weight of silane-modified silica composite are added to 100-200 parts by weight of ethylene glycol butyl ether and mixed evenly. Then, 80-120 parts by weight of alkenyl polyurethane and 1-4 parts by weight of initiator benzoyl peroxide are added. The mixture is reacted at 95-110℃ and 300-600rpm for 2-6 hours. After the reaction is completed, the solvent is removed under reduced pressure and the mixture is dried to obtain the interface-enhanced composite modifier.

[0046] The functional monomer is at least one of N-hydroxymethylacrylamide and hydroxyethyl acrylate; preferably, the functional monomer is a mixture of N-hydroxymethylacrylamide and hydroxyethyl acrylate in a mass ratio of 1:1.

[0047] Furthermore, the amino-containing silane coupling agent includes at least one of KH-550, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and N-(beta-aminoethyl)-gama-aminopropyltrimethoxysilane; the hydroxyl-containing silane coupling agent includes any one of N-(3-acryloyloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane and 3-[bis(2-hydroxyethyl)amino]propane-triethoxysilane; the double-bonded silane coupling agent includes at least one of 3-(methacryloyloxy)propyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, vinyltrimethoxysilane, and tetraethoxydivinyldisiloxane.

[0048] When spraying the wet-sprayed reinforcing agent, a cross-spraying method is used, the spraying pressure is 0.2-0.4MPa, and the spraying amount is 0.1-0.2kg / m².

[0049] A type of anti-peeling faux stone paint is obtained by using the aforementioned anti-peeling faux stone paint application process.

[0050] The beneficial effects of this invention are:

[0051] 1. This invention provides an anti-peeling faux stone paint and its construction process. By using a specially formulated inorganic aggregate layer to replace the traditional putty layer and intermediate coating layer, and introducing an interface-reinforcing composite modifier into the inorganic aggregate molding layer, combined with wet spraying and wet-jointing application of a wet-applied reinforcing agent, a strong and continuous transition interface layer is formed between the base layer, the cement-based inorganic aggregate layer, the faux stone paint dot layer, and the topcoat. Combined with the construction process, an organic-inorganic interface bridge is established during the initial setting of the inorganic aggregate, achieving a composite coating structure with gradual changes in mechanical properties and synergistic deformation from the concrete base layer to the final topcoat, thus completely solving long-standing quality problems such as peeling, hollowing, and detachment.

[0052] 2. This invention directly forms a leveling layer and a shaping layer by spraying an inorganic aggregate slurry. Relying on the particle size distribution and shaping capabilities of the inorganic aggregate itself, it achieves a textured surface and high fullness similar to dry-hanging stone. The stone-like effect is primarily achieved through a thick inorganic layer, while the colored dot layer only serves to enhance color and pattern. Compared to traditional systems that rely on multiple intermediate coats and thick colored dot layers to build texture, this invention significantly reduces the amount of colored dots used in the stone-like paint while achieving the same decorative effect. Calculations show that the amount of base coat used can be reduced by approximately 40% for the same decorative effect, thus effectively reducing system costs.

[0053] 3. The inorganic aggregate layer in this invention is mainly composed of inorganic components such as silicate cement and quartz sand, forming a rigid skeleton. Simultaneously, an organic / inorganic composite modification system, including alkenylated polyurethane, acrylic emulsion, and silica modified with a silane coupling agent, is introduced into the inorganic aggregate. Under the action of a wet-spraying reinforcing agent, a cross-linked network is further constructed between the layers. This gives the wall surface surface surface hardness and impact resistance close to that of a cement mortar layer, while effectively dispersing stress, improving crack resistance and freeze-thaw resistance. It is not prone to powdering or cracking with long-term use, providing a solid and reliable base for the stone-like paint.

[0054] 4. The inorganic aggregate dry powder of this invention integrates leveling, shaping, and coloring functions, simplifying the construction process, reducing reliance on multiple processes and different trades, and minimizing quality fluctuations caused by human factors. Through the built-in iron oxide pigment and stable inorganic system, it successfully overcomes the technical bottlenecks of traditional inorganic materials, such as difficulty in coloring and poor color development. The resulting coating structure is dense, effectively blocking the intrusion of moisture and corrosive media. Its bonding strength can reach over 2.5 MPa, adhesion reaches level 1, and it has a long resistance to artificial weathering, achieving a long-term protective and decorative effect with the same lifespan as the building wall. Detailed Implementation

[0055] The invention will be further described in detail below with reference to specific embodiments, but it should not be construed as limiting the scope of the invention to the following embodiments.

[0056] The raw materials described in this application are partially described; all other raw materials not described are commercially available.

[0057] The crack-resistant mortar was purchased from Anhui Ranhong New Building Materials Co., Ltd.

[0058] The water-based acrylic emulsion, brand name SA-212, was purchased from Anhui Zhongen Chemical Co., Ltd.

[0059] The silicone-acrylic emulsion was purchased from Weifang Changxu Building Materials Co., Ltd., model TG9854.

[0060] The water-based sand-like stone paint dots were purchased from Langfang Aoguang Energy Saving Technology Co., Ltd., model FS-001.

[0061] The fluorocarbon topcoat was purchased from Guangzhou Gaodeng Refreshing Technology Co., Ltd., model ZZ1.

[0062] The silicate cement was purchased from Wuhan Jiyesheng Chemical Co., Ltd., model 425 / 525.

[0063] The redispersible latex powder was purchased from Wuhan Runxingyuan Technology Co., Ltd., model 328.

[0064] The polyurethane was purchased from Dongguan Hongrui Polymer Materials Technology Co., Ltd., brand name US-60A10.

[0065] The silicon dioxide was purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model R812S.

[0066] The nano-montmorillonite was purchased from Zhejiang Fenghong New Material Co., Ltd., model DK32B.

[0067] The water-based mineral oil defoamer was purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model Drewplus T-4201A.

[0068] The exterior wall putty powder was purchased from Xianyang Yunerya Building Materials Co., Ltd.

[0069] Example 1

[0070] A process for applying a non-peeling faux stone paint includes the following steps:

[0071] Step 1: Base treatment: Inspect the concrete wall to be constructed to ensure that there are no hollow areas, no oil stains, and no loose dust. Repair and level any uneven areas with cement mortar.

[0072] Step 2, leveling with crack-resistant mortar: Mix crack-resistant mortar dry powder with water at a mass ratio of 100:25, stir at 600 rpm for 5 minutes, let stand and mature for 5 minutes, then stir again before use until a uniform crack-resistant mortar clinker without dry powder particles is formed; use a trowel to scrape and level the base surface, with a total thickness of approximately 3 mm.

[0073] Step 3: Marking the grid lines: According to the design drawings, use ink lines to mark the grid lines on the leveled and dried inorganic aggregate layer to determine the position and width of the imitation stone grid lines.

[0074] Step 4: Add water to the inorganic aggregate dry powder and stir it into a slurry in the same way as in Step 2. On the wall surface with the grid lines already marked, use a special spray gun with a nozzle diameter of 5mm to spray the design, with a spraying pressure of 0.8MPa and a design layer thickness controlled at 1.8mm.

[0075] Step 5: Application of wet-sprayed reinforcing agent: After the inorganic aggregate is molded, while it is still wet and not completely dry after initial setting, apply the wet-sprayed reinforcing agent evenly to its surface. The application rate should be controlled at 0.15 kg / m². 2 The spraying pressure is 0.3MPa and the spraying distance is 30cm. Spray the material evenly in a cross pattern to form a uniform film of reinforcing agent on the surface. After spraying the reinforcing agent, let it stand for 24 hours to allow the inorganic aggregate layer and reinforcing agent layer to harden fully.

[0076] Step 6, Grinding and Curing: Use 240-grit sandpaper to lightly grind the surface of the inorganic aggregate layer to remove loose sand and sharp protrusions. After grinding, remove surface dust and continue natural curing for 48 hours.

[0077] Step 7: Application of Alkali-Resistant Sealing Primer: Apply one coat of alkali-resistant sealing primer evenly to the dry inorganic aggregate layer using a roller, with a coverage rate of 0.12 kg / m². 2 Air dry for 4 hours.

[0078] Step 8, Application of Stone-like Paint Dots: After the alkali-resistant sealing primer has dried, use a stone-like paint spray gun with a nozzle diameter of 3mm and an air pressure of 0.4MPa to spray one coat of water-based sand-like stone-like paint dots using a cross-spraying method. After drying, spray another coat of water-based sand-like stone-like paint dots. The amount of paint used for each dot is 1.0kg / m². The stone-like paint dot layer should be dried for 24 hours.

[0079] Step 9: Topcoat Application: After the faux stone paint speckle layer is completely dry, apply one coat of fluorocarbon topcoat by roller, with a coverage rate of 0.10 kg / m². 2 Topcoat paint can give the coating excellent stain resistance, water resistance and weather resistance, and unify the coating gloss, thereby improving the overall decorative effect and service life.

[0080] The inorganic aggregate dry powder in the faux stone paint is composed of the following raw materials in parts by weight: 32 parts by weight of silicate cement, 40 parts by weight of quartz sand, 12 parts by weight of calcium carbonate, 4 parts by weight of redispersible latex powder, 0.3 parts by weight of hydroxypropyl methylcellulose ether, 2.7 parts by weight of iron oxide red pigment, 7.5 parts by weight of interface-enhancing composite modifier, 0.1 parts by weight of water-based mineral oil defoamer, 0.4 parts by weight of dodecyl alcohol ester, and 1 part by weight of sepiolite.

[0081] The preparation method of the interface-enhancing composite modifier is as follows:

[0082] (1) Under nitrogen protection, 100 parts by weight of polyurethane was dissolved in 400 parts by weight of tetrahydrofuran and stirred to obtain a polyurethane solution; 7 parts by weight of glycidyl acrylate was added and reacted at 72°C and 400 rpm for 3 h. After centrifugation, vacuum distillation and vacuum drying, alkenylated polyurethane was obtained.

[0083] (2) Mix 8 parts by weight of silica, 2 parts by weight of nano-montmorillonite and 300 parts by weight of 60wt% ethanol aqueous solution and sonicate. Add 3 parts by weight of silane coupling agent, adjust the pH to 4, react at 75℃ and 500rpm for 4h, filter, wash and vacuum dry to obtain silane-modified silica composite; the silane coupling agent is KH-550.

[0084] (3) 25 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 12 parts by weight of methyl methacrylate, 5 parts by weight of functional monomer, 15 parts by weight of butyl acrylate, and 10 parts by weight of silane-modified silica composite were added to 120 parts by weight of ethylene glycol butyl ether and mixed evenly. Then, 100 parts by weight of alkenyl polyurethane and 2.5 parts by weight of initiator benzoyl peroxide were added and reacted at 100°C and 400 rpm for 4 hours. After the reaction was completed, the solvent was removed under reduced pressure and dried to obtain the interface-enhancing composite modifier. The functional monomer was a mixture of N-hydroxymethylacrylamide and hydroxyethyl acrylate in a mass ratio of 1:1.

[0085] The crack-resistant mortar is commercially available.

[0086] The wet spray reinforcing agent is a commercially available water-based acrylic emulsion.

[0087] The alkali-resistant sealing primer is a commercially available silicone-acrylic emulsion.

[0088] The water-based sand-like stone paint dots are commercially available.

[0089] The fluorocarbon topcoat is commercially available.

[0090] Example 2

[0091] The process is basically the same as in Example 1, except that the silane coupling agent in step (2) of the preparation of the interface-enhancing composite modifier is vinyltris(2-methoxyethoxy)silane.

[0092] Example 3

[0093] The process is basically the same as in Example 1, except that the silane coupling agent in step (2) of the preparation of the interface-enhancing composite modifier is 3-[bis(2-hydroxyethyl)amino]propane-triethoxysilane.

[0094] Example 4

[0095] The process is basically the same as in Example 1, except that the functional monomer in step (3) of the preparation of the interface-enhancing composite modifier is N-hydroxymethylacrylamide.

[0096] Example 5

[0097] The process is basically the same as in Example 1, except that the functional monomer in step (3) of the preparation of the interface-enhancing composite modifier is hydroxyethyl acrylate.

[0098] Comparative Example 1

[0099] The process is basically the same as in Example 1, except that the inorganic aggregate dry powder in the stone-like paint does not contain an interface-enhancing composite modifier. It is composed of the following raw materials in parts by weight: 39.5 parts by weight of silicate cement, 40 parts by weight of quartz sand, 12 parts by weight of calcium carbonate, 4 parts by weight of redispersible latex powder, 0.3 parts by weight of hydroxypropyl methylcellulose ether, 2.7 parts by weight of iron oxide red pigment, 0.1 parts by weight of water-based mineral oil defoamer, 0.4 parts by weight of dodecyl alcohol ester, and 1 part by weight of sepiolite.

[0100] Comparative Example 2

[0101] The process is basically the same as in Example 1, except that the silane coupling agent in step (2) of the preparation of the interface-enhancing composite modifier is n-octyltriethoxysilane without amino, double bond, or hydroxyl modification.

[0102] Comparative Example 3

[0103] The method is basically the same as in Example 1, except that the preparation method of the interface-enhancing composite modifier is as follows:

[0104] (1) Mix 8 parts by weight of silica, 2 parts by weight of nano-montmorillonite and 300 parts by weight of 60wt% ethanol aqueous solution and sonicate. Add 3 parts by weight of silane coupling agent, adjust the pH to 4, react at 75℃ and 500rpm for 4h, filter, wash and vacuum dry to obtain silane-modified silica composite; the silane coupling agent is KH-550.

[0105] (2) 25 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 12 parts by weight of methyl methacrylate, 5 parts by weight of N-hydroxymethylacrylamide, 15 parts by weight of butyl acrylate, and 10 parts by weight of silane-modified silica composite were added to 120 parts by weight of ethylene glycol butyl ether and mixed evenly. Then, 100 parts by weight of polyurethane and 2.5 parts by weight of initiator benzoyl peroxide were added and reacted at 100℃ and 400rpm for 4h. After the reaction was completed, the solvent was removed under reduced pressure and dried to obtain the interface-enhanced composite modifier.

[0106] Comparative Example 4

[0107] The process is basically the same as in Example 1, except that the preparation method of the interface-enhancing composite modifier is as follows: (1) Under nitrogen protection, 100 parts by weight of polyurethane is dissolved in 400 parts by weight of tetrahydrofuran and stirred to obtain a polyurethane solution; 7 parts by weight of glycidyl acrylate is added, and the reaction is carried out at 72°C and 400 rpm for 3 hours. After centrifugation, vacuum distillation and vacuum drying are carried out to obtain alkenylated polyurethane.

[0108] (2) 25 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 12 parts by weight of methyl methacrylate, 5 parts by weight of N-hydroxymethylacrylamide, 15 parts by weight of butyl acrylate and 10 parts by weight of silica were added to 120 parts by weight of ethylene glycol butyl ether and mixed evenly. Then, 100 parts by weight of alkenyl polyurethane and 2.5 parts by weight of initiator benzoyl peroxide were added and reacted at 100℃ and 400rpm for 4h. After the reaction was completed, the solvent was removed under reduced pressure and dried to obtain the interface-enhanced composite modifier.

[0109] Comparative Example 5

[0110] The method is basically the same as in Example 1, except that no functional monomer is added in step (3) of the preparation method of the interface-enhancing composite modifier. The preparation method is as follows:

[0111] (1) Under nitrogen protection, 100 parts by weight of polyurethane was dissolved in 400 parts by weight of tetrahydrofuran and stirred to obtain a polyurethane solution; 7 parts by weight of glycidyl acrylate was added and reacted at 72°C and 400 rpm for 3 h. After centrifugation, vacuum distillation and vacuum drying, alkenylated polyurethane was obtained.

[0112] (2) Mix 8 parts by weight of silica, 2 parts by weight of nano-montmorillonite and 300 parts by weight of 60wt% ethanol aqueous solution and sonicate. Add 3 parts by weight of silane coupling agent, adjust the pH to 4, react at 75℃ and 500rpm for 4h, filter, wash and vacuum dry to obtain silane-modified silica composite; the silane coupling agent is KH-550.

[0113] (3) 25 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 12 parts by weight of methyl methacrylate, 15 parts by weight of butyl acrylate, and 10 parts by weight of silane-modified silica composite were added to 120 parts by weight of ethylene glycol butyl ether and mixed evenly. Then, 100 parts by weight of alkenyl polyurethane and 2.5 parts by weight of initiator benzoyl peroxide were added and reacted at 100℃ and 400rpm for 4h. After the reaction was completed, the solvent was removed under reduced pressure and dried to obtain the interface-enhanced composite modifier.

[0114] Comparative Example 6

[0115] The process is basically the same as in Example 1, except that in step four of the construction process of the anti-detachment faux stone paint, the inorganic aggregate dry powder is replaced with commercially available exterior wall putty powder, while the other steps remain unchanged.

[0116] Step 4: Add water to the inorganic aggregate dry powder and stir it into a slurry in the same way as in Step 2. On the wall surface with the grid lines already marked, use a special spray gun with a nozzle diameter of 5mm to spray the design, with a spraying pressure of 0.8MPa and a design layer thickness controlled at 1.8mm.

[0117] Test Example 1

[0118] Adhesion strength performance test: The anti-detachment imitation stone paint prepared in the above examples and comparative examples was tested according to the national standard JG / T24-2018 "Synthetic Resin Emulsion Sand-textured Architectural Coatings". Each group was tested 5 times and the average value was taken. The results are shown in Table 1.

[0119] Adhesion test: The anti-peeling imitation stone paint prepared in the above examples and comparative examples was tested according to the national standard GB / T1720-2020 "Circle Cross Test of Paint Film". The results are shown in Table 1.

[0120] Aging resistance test: The anti-peeling imitation stone paint prepared in the above examples and comparative examples was tested in accordance with the national standard GB / T1865-2009 "Artificial climate aging and artificial radiation exposure of paints and varnishes with filtered xenon arc radiation". The time of initial peeling, cracking, wrinkling, blistering and peeling were observed. The results are shown in Table 1.

[0121] Table 1 Performance Test Results

[0122] Bond strength (MPa) Adhesion rating Aging resistance time, days Example 1 2.69 Level 1 52 Example 2 2.61 Level 1 50 Example 3 2.53 Level 1 48 Example 4 2.57 Level 1 43 Example 5 2.63 Level 1 45 Comparative Example 1 0.98 Level 4 24 Comparative Example 2 1.93 Level 2 37 Comparative Example 3 1.68 Level 3 34 Comparative Example 4 1.75 Level 3 33 Comparative Example 5 1.81 Level 2 35 Comparative Example 6 0.79 Level 4 21

[0123] The results above show that the anti-peeling faux stone paint prepared by this invention has good bonding performance, high adhesion grade, and good aging resistance, thus extending the service life of the faux stone paint. Table 1 shows that compared with Comparative Example 1 (without the interface-reinforcing composite modifier) ​​or Comparative Example 6 (using the traditional putty system), the bonding strength of Examples 1-5 is greater than 2.5 MPa, the adhesion grade is 1, and the aging resistance time is extended to 43-52 days. In contrast, the bonding strength of Comparative Examples 1 and 6 is only 0.98 MPa and 0.79 MPa, respectively, the adhesion grade is 4, and the aging resistance time is only 24 days and 21 days, respectively. This indicates that introducing an interface-reinforcing composite modifier composed of alkenyl polyurethane / acrylic acid / silane-modified silica into the inorganic aggregate system can significantly improve the overall mechanical properties and interlayer adhesion of the thick inorganic aggregate layer, forming a stable and dense support layer, fundamentally improving the problems of peeling, blistering, and detachment in traditional faux stone paint systems.

[0124] Examples 1-3 all employed alkenylated polyurethane and silica composites modified with coupling agents containing amino, hydroxyl, or double bonds in silanes, and introduced functional monomer combinations composed of N-hydroxymethylacrylamide and hydroxyethyl acrylate. Example 1 used aminosilane KH-550, exhibiting a bonding strength of 2.69 MPa and an aging resistance of 52 days. Example 2 used vinylsilane containing double bonds, and Example 3 used triethoxysilane containing hydroxyl and amino groups; the bonding strength remained above 2.5 MPa, and the aging resistance was 48-50 days. This demonstrates that although different active silanes differ in chemical structure, as long as active functional groups such as amino, hydroxyl, or double bonds are introduced, they can effectively connect cement hydration products, inorganic aggregates, and organic polymers through chemical bonding and polar interactions, improving interfacial adhesion and anti-aging ability. Among these, aminosilanes exhibit a more complete reaction at the cement-based interface.

[0125] Compared to Example 1, Examples 4-5 only changed the type of functional monomer: Example 4 contained only N-hydroxymethylacrylamide, and Example 5 contained only hydroxyethyl acrylate. The bond strength and adhesion of both remained at a high level, reaching 2.57 MPa-2.63 MPa, with adhesion grade 1 for both. However, their aging resistance times were 43 days and 45 days respectively, slightly lower than the 52 days of Example 1, which contained both N-hydroxymethylacrylamide and hydroxyethyl acrylate. This indicates that N-hydroxymethylacrylamide provides self-crosslinking functional groups, enabling crosslinking reactions under thermal or alkaline conditions during film formation and subsequent processes, significantly improving the density, water resistance, and hardness of the coating. The hydroxyl groups provided by hydroxyethyl acrylate can form hydrogen bonds with inorganic surfaces and provide more reaction anchoring points for subsequent wet-sprayed reinforcing agents, greatly enhancing the interlayer adhesion between the inorganic aggregate layer and the organic reinforcing agent layer. When used in combination, both can simultaneously improve the internal crosslinking density and multi-interface bonding strength of the coating, thereby achieving superior long-term aging resistance.

Claims

1. A construction process for an anti-peeling faux stone paint, characterized in that, Includes the following steps: Step 1: Apply crack-resistant mortar to the wall base layer to form a leveling layer; Step 2: Mark the grid lines on the dry leveling layer; Step 3: Spray inorganic aggregate slurry onto the leveled layer that has been divided into sections to form a shaping layer. The shaping layer is composed of inorganic aggregate slurry containing an interface-reinforcing composite modifier. Step 4: While the molding layer is initially set but not completely dry, immediately spray a wet-spray reinforcing agent onto its wet surface to form a reinforcing agent layer; Step 5: Curing and polishing the molding layer and reinforcing agent layer; Step 6: Apply alkali-resistant sealing primer, imitation stone paint dots, and topcoat in sequence.

2. The construction process of the anti-peeling faux stone paint as described in claim 1, characterized in that, The total thickness of the inorganic aggregate leveling layer and the shaping layer is 2-6mm.

3. The construction process of the anti-peeling faux stone paint as described in claim 1, characterized in that, The inorganic aggregate slurry is prepared by mixing the inorganic aggregate dry powder with water at a mass ratio of 100:(18-30).

4. The construction process of the anti-peeling faux stone paint as described in claim 3, characterized in that, The inorganic aggregate powder, by weight, comprises the following components: 20-40 parts of silicate cement; 32-50 parts of quartz sand; 10-15 parts calcium carbonate; 2-8 parts of redispersible latex powder; 5-10 parts of interface-enhancing composite modifier.

5. The construction process of the anti-peeling faux stone paint as described in claim 1, characterized in that, The preparation method of the interface-enhancing composite modifier includes the following steps: (1) React polyurethane with glycidyl acrylate to obtain alkenyl polyurethane; (2) Reaction of silica and nano-montmorillonite with a silane coupling agent containing an active functional group yields a silane-modified silica composite; the active functional group includes at least one of amino, hydroxyl and double bond; (3) The alkenyl polyurethane obtained in step (1), the silane-modified silica composite obtained in step (2), and a monomer mixture including 2-acrylamido-2-methylpropanesulfonic acid, functional monomers, methyl methacrylate and butyl acrylate are subjected to graft copolymerization in the presence of an initiator to obtain the interface-enhancing composite modifier; the functional monomer is one or two of N-hydroxymethylacrylamide and hydroxyethyl acrylate.

6. The construction process of the anti-peeling faux stone paint as described in claim 5, characterized in that, The reaction conditions in step (1) are 60-80℃ and 300-600rpm for 2-6 hours.

7. The construction process of the anti-peeling faux stone paint as described in claim 5, characterized in that, The reaction conditions in step (2) are 70-85℃ and 400-700rpm for 2-8 hours.

8. The construction process of the anti-peeling faux stone paint as described in claim 5, characterized in that, The reaction conditions in step (3) are 95-110℃ and 300-600rpm for 2-6 hours.

9. The construction process of the anti-peeling faux stone paint as described in claim 1, characterized in that, When spraying the wet-sprayed reinforcing agent, a cross-spraying method is used, the spraying pressure is 0.2-0.4MPa, and the spraying amount is 0.1-0.2kg / m².

10. A stone-like paint that prevents peeling, characterized in that, The process of applying the anti-detachment faux stone paint as described in any one of claims 1-9 is adopted.