Stain-resistant stone-like coating and preparation method thereof

Abstract

The invention discloses a stain-resistant stone-like coating and a preparation method thereof, and belongs to the technical field of stone-like coatings. Comprising the following raw materials in parts by mass: 50-70 parts of water, 0.3-0.5 part of a dispersing agent, 0.5-1.5 parts of a wetting agent, 23-35 parts of an acrylic emulsion, 3-5 parts of a coalescing agent, 2-3 parts of an anti-settling agent, 2-8 parts of a stain-resistant additive, 21-32 parts of colored rock slices, 0.08-0.12 part of a defoaming agent and 0.2-0.8 part of a thickening agent. Wherein the stain-resistant additive can significantly improve the stain resistance and aging resistance of the coating; the coating can be prepared only through two-step dispersion stirring, and is suitable for industrial large-scale production; due to the stain-resistant characteristic, the manual cleaning frequency is reduced, and the building facade maintenance cost is reduced; therefore, compared with a traditional stone-like coating, the prepared stone-like coating has the advantages that the stain resistance and the aging resistance are greatly improved, and the stone-like coating has important value in the technical field of stone-like coatings.

Description

Technical Field

[0001] The invention belongs to the technical field of stone-imitation coatings, and in particular relates to a stain-resistant stone-imitation coating and a preparation method thereof. Background Art

[0002] With the rapid development of my country's economy, the continuous improvement of living standards, and the ever-improving urban landscape, people's demands for decorative wall designs are becoming increasingly demanding. Natural stone is highly regarded for its vibrant, natural qualities and excellent protective properties. However, natural stone construction is complex and expensive. Furthermore, natural stone is affected by factors such as its origin and environment, resulting in certain limitations in its use and development. Consequently, imitation stone coatings are gaining increasing attention.

[0003] Stone-like paint is a man-made coating that can be applied directly onto cement mortar, concrete, and steel structures. In the architectural decoration sector, stone-like paint is highly sought after for its ability to mimic the texture and decorative effects of natural stone. Traditional stone-like paints primarily utilize a combination of emulsions, fillers, and additives to create a coating with a stone-like texture. These coatings are widely used in building exteriors, interior decoration, and landscape design. However, with the acceleration of urbanization and rising environmental protection requirements, the limitations of traditional stone-like paints are becoming increasingly apparent, particularly in terms of stain resistance, which significantly impacts their service life and decorative effect. Natural stone surfaces typically have a dense structure and low porosity, effectively resisting the adhesion of pollutants. However, due to deficiencies in their film-forming materials and formulation, traditional stone-like paints often exhibit microporous or uneven surfaces, which readily absorb dust, oil, and other contaminants from the air. This can cause the coating surface to become dirty, blackened, and even harbor mold, which not only diminishes the decorative effect but also increases cleaning and maintenance costs. In addition, imitation stone coatings will fade severely under ultraviolet light shortly after the completion of many building facades, which also limits the application of imitation stone coatings. Therefore, it is urgent to solve the above problems to meet the higher demands in the field of imitation stone coating technology. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a stain-resistant stone-like paint and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A stain-resistant imitation stone paint comprises the following raw materials in parts by weight: 50-70 parts of water, 0.3-0.5 parts of a dispersant, 0.5-1.5 parts of a wetting agent, 23-35 parts of an acrylic emulsion, 3-5 parts of a film-forming aid, 2-3 parts of an anti-precipitation agent, 2-8 parts of a stain-resistant aid, 21-32 parts of colored rock flakes, 0.08-0.12 parts of a defoaming agent, and 0.2-0.8 parts of a thickener.

[0007] As a further technical solution, the dispersant is one of sodium dodecyl sulfate and sodium dodecylbenzenesulfonate.

[0008] As a further technical solution, the wetting agent is one or a combination of polyoxyethylene fatty alcohol ether, polyoxyethylene alkylphenol ether, and fatty alcohol polyoxyethylene ether.

[0009] As a further technical solution, the film-forming aid is one of ethylene glycol butyl ether acetate, propylene glycol butyl ether, propylene glycol methyl ether acetate and dodecyl alcohol ester.

[0010] As a further technical solution, the anti-precipitation agent is one of organic bentonite and polyamide wax.

[0011] As a further technical solution, the defoaming agent is a paraffin defoaming agent.

[0012] As a further technical solution, the thickener is one of hydroxyethyl cellulose and hydroxypropyl methyl cellulose.

[0013] As a further technical solution, the anti-fouling agent is prepared by the following steps:

[0014] Step 1. A thermometer, a reflux condenser, and a constant pressure dropping funnel were installed on a dry three-necked flask. Vacuuming and nitrogen filling were cycled three times to establish an inert reaction environment. Pentaerythritol was used as a reaction raw material and mixed with the solvent toluene. Then, phosphorus trichloride was added dropwise to the flask through a constant pressure dropping funnel. After the addition was completed, the device was heated until the temperature reached 78° C., the temperature was maintained constant, and the reaction was refluxed for 5 hours. After the reaction was completed, the solvent and excess phosphorus trichloride were removed by rotary evaporation to obtain product 1;

[0015] As a further technical solution, the ratio of pentaerythritol, toluene and phosphorus trichloride in step 1 is 13.6 g:100 mL:28.2 g.

[0016] In step 1, pentaerythritol and phosphorus trichloride react with a slight excess of phosphorus trichloride to ensure a complete reaction; the reaction formula is as follows:

[0017]

[0018] Step 2: Install a thermometer, a condenser, and a constant pressure dropping funnel on a dry three-necked flask, vacuum-fill with nitrogen for three cycles to establish an inert reaction environment, mix 2,4-dihydroxybenzophenone and product 1 as reaction raw materials with the solvent toluene, then mix sodium hydroxide with distilled water, stir to dissolve the sodium hydroxide, and slowly add it dropwise to the flask through a dropping funnel. After the addition is completed, heat the device until the temperature stabilizes at 70 ° C. Stir and react at this temperature for 5 hours. After the reaction is completed, filter, use a rotary evaporator for rotary evaporation, and purify by column chromatography to obtain product 2;

[0019] As a further technical solution, in step 2, the ratio of 2,4-dihydroxybenzophenone, product 1, toluene, sodium hydroxide and distilled water is 21.4 g:26.3 g:150 mL:3.9 g:20 mL.

[0020] In step 2, sodium hydroxide provides an alkaline environment to catalyze the reaction between 2,4-dihydroxybenzophenone and product 1. In addition, the hydroxyl group at the 2-position of 2,4-dihydroxybenzophenone forms a hydrogen bond with the carbonyl group, which is not easily broken. The reaction formula is as follows:

[0021]

[0022] Step 3: Install a thermometer, a condenser, and a constant pressure dropping funnel on a dry three-necked flask, and perform a vacuum-nitrogen filling cycle three times to establish an inert reaction environment. Mix product 2 and bisaminopropyl polydimethylsiloxane as reaction raw materials with N,N-dimethylformamide and potassium carbonate, and stir evenly. Control the reaction temperature to 80°C, stir the reaction for 12 hours, and after the reaction is complete, filter, and distill under reduced pressure to obtain a stain-resistant additive.

[0023] As a further technical solution, in step 3, the ratio of the amount of product 2, bisaminopropyl polydimethylsiloxane, N,N-dimethylformamide, and potassium carbonate is 85.6g:10g:200mL:27.6g.

[0024] In step 3, potassium carbonate is used as a catalyst to cause nucleophilic substitution between product 2 and bisaminopropyl polydimethylsiloxane. Excessive amount of product 2 is added to fully react to obtain a stain-resistant additive. The structure of the stain-resistant additive is shown below:

[0025]

[0026] The prepared anti-fouling additive is mainly composed of polysiloxane, with anti-ultraviolet aging groups connected at both ends. Among them, polysiloxane has Si-O-Si as the main chain, high bond energy, strong chemical inertness, and can resist the erosion of ultraviolet rays and pollutants; and the densely arranged -CH3 forms a "molecular-level brush" that makes it difficult for pollutants such as dust and oil to adhere. Even if they do adhere, they are easily washed away by rain, further reducing the surface energy of the substrate and improving the anti-fouling performance. In addition, the connected anti-ultraviolet aging groups contain benzophenone groups and phosphite groups at the same time. The benzophenone, as a UV absorber, can synergistically enhance the phosphite group, an auxiliary antioxidant, and significantly enhance the UV resistance of the substrate.

[0027] The present invention also provides a method for preparing a stain-resistant imitation stone coating, comprising the following steps:

[0028] Step 1: first add water, dispersant and wetting agent into the disperser in sequence and stir;

[0029] Step 2: Add acrylic emulsion, film-forming agent, anti-precipitation agent, anti-fouling agent, colored rock flakes and defoaming agent into the disperser in sequence, stir evenly, and finally add thickener and stir to adjust viscosity to prepare anti-fouling stone-like paint.

[0030] Beneficial effects of the present invention:

[0031] 1. The present invention prepares the anti-fouling additive through a three-step reaction. The anti-fouling additive molecule contains multiple functional groups, which can significantly improve the anti-fouling and anti-aging properties of the coating;

[0032] 2. The coating preparation only requires two steps of dispersion and stirring, without the need for complex processes or special equipment, and is suitable for industrial large-scale production;

[0033] 3. It can be directly applied to various base surfaces such as cement mortar, concrete, and steel structures. It is compatible with the construction process of traditional imitation stone coatings and is convenient for rapid replacement and application in the field of architectural decoration.

[0034] 4. The anti-fouling property reduces the frequency of manual cleaning and reduces the maintenance cost of building facades. It is especially suitable for high-rise buildings and large-area decoration scenes.

[0035] Therefore, the imitation stone coating prepared by the present invention has greatly improved stain resistance and aging resistance compared with traditional imitation stone coatings, and has important value in the field of imitation stone coating technology. DETAILED DESCRIPTION

[0036] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0037] Example 1

[0038] Preparation of anti-fouling additives:

[0039] Step 1. A thermometer, a reflux condenser, and a constant pressure dropping funnel were installed on a dry three-necked flask. The vacuum-filling-nitrogen cycle was repeated three times to establish an inert reaction environment. 13.6 g of pentaerythritol was used as a reaction raw material and mixed with 100 mL of toluene solvent. Then, 28.2 g of phosphorus trichloride was added dropwise to the flask through a constant pressure dropping funnel. After the addition was complete, the device was heated until the temperature reached 78 ° C. The temperature was maintained constant and the reaction was refluxed for 5 h. After the reaction was completed, the solvent and excess phosphorus trichloride were removed by rotary evaporation to obtain product 1;

[0040] Step 2, a thermometer, a condenser and a constant pressure dropping funnel were installed on a dry three-necked flask, and the vacuum-nitrogen filling cycle was repeated three times to establish an inert reaction environment. 41.8 g of 2,4-dihydroxybenzophenone and 52.6 g of product 1 were mixed as reaction raw materials with 300 mL of solvent toluene, and then 7.8 g of sodium hydroxide was mixed with 40 mL of distilled water. The sodium hydroxide was dissolved by stirring and slowly added dropwise to the flask through a dropping funnel. After the addition was completed, the device was heated until the temperature stabilized at 70 ° C. The reaction was stirred at this temperature for 5 h. After the reaction was completed, it was filtered, and after rotary evaporation using a rotary evaporator, it was purified by column chromatography to obtain product 2;

[0041] Step 3. A thermometer, a condenser, and a constant pressure dropping funnel were installed on a dry three-necked flask, and the vacuum-nitrogen filling cycle was repeated three times to establish an inert reaction environment. 85.6 g of product 2 and 10 g of bisaminopropyl polydimethylsiloxane (produced by Wuhan Jushun Chemical Co., Ltd.) were used as reaction raw materials. They were mixed with 200 mL of N, N-dimethylformamide and 27.6 g of potassium carbonate and stirred evenly. The reaction temperature was controlled to 80 ° C. The reaction was stirred for 12 h. After the reaction was completed, the mixture was filtered and distilled under reduced pressure to obtain a stain-resistant additive.

[0042] Example 2

[0043] Preparation of stain-resistant imitation stone coating:

[0044] Step 1: First, add 50g water, 0.3g sodium lauryl sulfate and 0.5g polyoxyethylene fatty alcohol ether into a disperser in sequence and stir;

[0045] Step 2: 23 g of acrylic emulsion (BASF model Acronal 296DSap), 3 g of ethylene glycol butyl ether acetate, 2 g of polyamide wax, 2 g of the anti-fouling agent prepared in Example 1, 21 g of colored rock flakes and 0.08 g of defoamer (BYK-011) were added to the disperser in sequence, stirred evenly, and finally 0.2 g of hydroxyethyl cellulose was added and stirred to adjust the viscosity to obtain a stain-resistant imitation stone coating.

[0046] Example 3

[0047] Preparation of stain-resistant imitation stone coating:

[0048] Step 1: First, add 60g of water, 0.4g of sodium dodecylbenzenesulfonate and 1.0g of polyoxyethylene alkylphenol ether into a disperser in sequence and stir;

[0049] Step 2: 29 g of acrylic emulsion (BASF model Acronal 296DSap), 4 g of propylene glycol butyl ether, 2.5 g of polyamide wax, 5 g of the anti-fouling agent prepared in Example 1, 25 g of colored rock flakes and 0.10 g of defoamer (BYK-011) were added to the disperser in sequence, stirred evenly, and finally 0.5 g of hydroxypropyl methylcellulose was added and stirred to adjust the viscosity to obtain a stain-resistant imitation stone coating.

[0050] Example 4

[0051] Preparation of stain-resistant imitation stone coating:

[0052] Step 1: First, add 70g of water, 0.5g of sodium dodecylbenzene sulfonate and 1.5g of polyoxyethylene alkylphenol ether into a disperser in sequence and stir;

[0053] Step 2: 35 g of acrylic emulsion (BASF model Acronal 296DSap), 5 g of dodecyl alcohol ester, 3 g of polyamide wax, 8 g of the stain-resistant additive prepared in Example 1, 32 g of colored rock flakes, and 0.12 g of defoamer (BYK-011) were added to the disperser in sequence, stirred evenly, and finally 0.8 g of hydroxypropyl methylcellulose was added and stirred to adjust the viscosity to obtain a stain-resistant imitation stone coating.

[0054] Comparative Example 1

[0055] The anti-fouling agent in Example 4 was replaced by ordinary polysiloxane of the same mass, and the remaining steps were the same as those in Example 4 to obtain the coating.

[0056] Comparative Example 2

[0057] Use commercially available traditional stone-like paint.

[0058] The following performance tests were performed on Examples 2, 3, and 4 and Comparative Examples 1 and 2:

[0059] Adopt the construction industry standard JG / T 24-2000 "Synthetic resin emulsion sand-walled architectural coating";

[0060] The measured results are shown in the following table:

[0061]

[0062] As can be seen from the above table, after adding the anti-fouling additive, the anti-fouling and aging resistance of the embodiment of the present invention are higher than those of the comparative example. Therefore, the imitation stone coating prepared by the present invention has both anti-fouling and aging resistance, and has important application value in the field of imitation stone coating technology.

[0063] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0064] The above contents are merely examples and explanations of the present invention. Any modifications or additions made by those skilled in the art to the described specific embodiments, or replacements made in a similar manner, shall fall within the scope of protection of the present invention.

Claims

1. A stain-resistant imitation stone paint, characterized in that: The invention comprises the following raw materials in parts by weight: 50-70 parts of water, 0.3-0.5 parts of dispersant, 0.5-1.5 parts of wetting agent, 23-35 parts of acrylic emulsion, 3-5 parts of film-forming aid, 2-3 parts of anti-precipitation agent, 2-8 parts of anti-fouling aid, 21-32 parts of colored rock flakes, 0.08-0.12 parts of defoaming agent and 0.2-0.8 parts of thickener.

2. The stain-resistant stone-like paint according to claim 1, characterized in that: The anti-fouling auxiliary agent is prepared by the following steps: Step 1: After pentaerythritol and toluene are mixed, phosphorus trichloride is added, and the mixture is refluxed at 78° C. for 5 hours. The reaction is completed to obtain product 1; Step 2: After mixing 2,4-dihydroxybenzophenone, product 1 and toluene, sodium hydroxide and distilled water were mixed, and the mixture was added to a flask. The mixture was stirred at 70° C. for 5 h. The reaction was completed to obtain product 2. Step 3: Mix and stir the product 2, bisaminopropyl polydimethylsiloxane, N,N-dimethylformamide and potassium carbonate, and react at 80° C. for 12 hours. The reaction is completed to obtain a stain-resistant additive.

3. The stain-resistant stone-like paint according to claim 2, characterized in that: In step 1, the ratio of pentaerythritol, toluene and phosphorus trichloride is 13.6 g:100 mL:28.2 g.

4. The stain-resistant stone-like paint according to claim 2, characterized in that: In step 2, the ratio of 2,4-dihydroxybenzophenone, product 1, toluene, sodium hydroxide and distilled water is 21.4 g:26.3 g:150 mL:3.9 g:20 mL.

5. The stain-resistant stone-like paint according to claim 2, characterized in that: In step 3, the ratio of product 2, bisaminopropyl polydimethylsiloxane, N,N-dimethylformamide, and potassium carbonate is 85.6 g:10 g:200 mL:27.6 g.

6. The stain-resistant imitation stone paint according to claim 1, characterized in that: The dispersant is one of sodium dodecyl sulfate and sodium dodecylbenzene sulfonate.

7. The stain-resistant stone-like paint according to claim 1, characterized in that: The wetting agent is one or a combination of polyoxyethylene fatty alcohol ether, polyoxyethylene alkylphenol ether, and fatty alcohol polyoxyethylene ether.

8. The stain-resistant stone-like paint according to claim 1, characterized in that: The film-forming aid is one of ethylene glycol butyl ether acetate, propylene glycol butyl ether, propylene glycol methyl ether acetate and dodecyl alcohol ester.

9. The stain-resistant stone-like paint according to claim 1, characterized in that: The film-forming aid is one of ethylene glycol butyl ether acetate, propylene glycol butyl ether, propylene glycol methyl ether acetate and dodecyl alcohol ester.

10. The method for preparing a stain-resistant stone-like coating according to any one of claims 1 to 9, characterized in that: The following steps are involved: First, add water, dispersant and wetting agent into the disperser in sequence and stir; then add acrylic emulsion, film-forming agent, anti-precipitation agent, anti-fouling agent, colored rock flakes and defoaming agent into the disperser in sequence, stir evenly, and finally add thickener and stir to prepare the stain-resistant imitation stone paint.

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