A stain-resistant, high-hardness nano-ceramic paint and its preparation method

Abstract

This application relates to the field of coating technology, specifically disclosing a stain-resistant, high-hardness nano-ceramic paint and its preparation method. The stain-resistant, high-hardness nano-ceramic paint comprises the following components in parts by weight: 90-120 parts of acrylate emulsion, 40-60 parts of nano-inorganic silicone resin, 5-10 parts of film-forming aid, 20-30 parts of titanium dioxide, 10-20 parts of filler, 0.5-2 parts of formaldehyde-removing aid, 2-3 parts of dispersant, 0.5-1.5 parts of defoamer, 1-2 parts of thickener, and 10-20 parts of water. The acrylate emulsion has a solid content of 46-48% and is made from the following raw materials: a mixed monomer composed of methyl methacrylate, n-butyl acrylate, isooctyl acrylate, and methacrylic acid; a functional monomer composed of triethoxysilane succinic anhydride; a crosslinking monomer composed of diacetone acrylamide and dihydrazine adipate; an emulsifier; an initiator; and water. This application improves both the stain resistance and hardness of the ceramic paint by enhancing the film density of the coating system.

Description

Technical Field

[0001] This application relates to the field of coating technology, and more specifically, to a stain-resistant, high-hardness nano-ceramic paint and its preparation method. Background Technology

[0002] With the rapid development of modern construction, automobile manufacturing, and home decoration, the market has placed higher demands on the comprehensive performance of high-performance coatings. Traditional coatings often fail to meet increasingly stringent application requirements in terms of hardness, stain resistance, weather resistance, and environmental performance. For example, while conventional acrylic coatings have advantages such as strong adhesion and good weather resistance, their balance between hardness and stain resistance is poor, and they are prone to scratches and stains after long-term use. Inorganic coatings, although possessing high hardness, generally suffer from insufficient flexibility and are prone to brittleness. In addition, the release of volatile organic compounds (VOCs) and harmful substances such as formaldehyde from coatings has also raised significant concerns about their environmental performance.

[0003] In recent years, the introduction of nanotechnology has opened up new avenues for improving coating performance. By adding inorganic materials such as nano-silica and titanium dioxide, the hardness, abrasion resistance, and UV resistance of coatings have been significantly improved. However, the dispersion stability of nanoparticles and their interfacial bonding with organic resin matrices remain technical bottlenecks restricting their widespread application. For example, nanoparticles are prone to agglomeration, reducing film density and leading to decreased stain resistance; while insufficient compatibility between inorganic components and organic resins weakens the mechanical strength and adhesion of the coating. Although existing technologies have optimized the emulsion polymerization process by adjusting the emulsifier system or introducing crosslinking monomers, problems such as uneven latex particle size distribution and insufficient film density still exist, limiting further improvements in the overall performance of the coating.

[0004] For antifouling performance, existing technologies mostly rely on the introduction of low surface energy materials (such as organosilicon and fluorocarbon resin), but these are expensive and have poor compatibility with the base resin, and are prone to migration failure after long-term use. Some related technologies achieve antifouling by improving the hydrophobicity and oleophobicity of the coating, but they ignore the film density of the coating system, which can easily lead to a decline in the mechanical properties of the coating. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a stain-resistant, high-hardness nano-ceramic paint and its preparation method. This application improves both the stain resistance and hardness of the ceramic paint by enhancing the film density of the coating system.

[0006] In the first aspect, this application provides a stain-resistant, high-hardness nano-ceramic paint, employing the following technical solution:

[0007] A stain-resistant, high-hardness nano-ceramic paint comprises the following components in parts by weight: 90-120 parts acrylic emulsion, 40-60 parts nano-inorganic silicone resin, 5-10 parts film-forming aid, 20-30 parts titanium dioxide, 10-20 parts filler, 0.5-2 parts formaldehyde removal aid, 2-3 parts dispersant, 0.5-1.5 parts defoamer, 1-2 parts thickener, and 10-20 parts water;

[0008] The acrylate emulsion has a solid content of 46-48% and is made from the following raw materials: methyl methacrylate, n-butyl acrylate, a mixed monomer composed of isooctyl acrylate and methacrylic acid, a functional monomer composed of triethoxysilane succinic anhydride, a crosslinking monomer composed of diacetone acrylamide and dihydrazine adipate, an emulsifier, an initiator, and water.

[0009] The acrylate emulsion polymer prepared in this application comprises a mixture of monomers. Methyl methacrylate acts as a hard monomer, enhancing the polymer's rigidity, hardness, and weather resistance, and regulating its glass transition temperature. Butyl acrylate and isooctyl acrylate act as soft monomers, imparting flexibility, elasticity, and adhesion to the polymer. Isooctyl acrylate, due to its long-chain structure, is more flexible and hydrophobic. Methacrylic acid contains carboxylic acid groups, enhancing emulsion stability, participating in crosslinking reactions, and improving wash resistance and mechanical strength. Among the functional and crosslinking monomers, the anhydride groups in triethoxysilane succinic anhydride can participate in crosslinking reactions, enhancing emulsion stability. Furthermore, the silanoxy groups in triethoxysilane succinic anhydride readily react with inorganic substances, thereby improving the adhesion between the coating and the inorganic matrix. Diacetone acrylamide and dihydrazide adipic acid form a ketone-hydrazine crosslinking system. After film formation, covalent bonds are formed through the ketone-hydrazine reaction, achieving post-crosslinking, enhancing the system's mechanical properties and density, thereby improving hardness and stain resistance.

[0010] More preferably, the acrylate emulsion is prepared by the following steps:

[0011] Mix 80-90% of the emulsifier, functional monomer, crosslinking monomer with water, heat and stir, and simultaneously add 80-90% of the mixed monomers to obtain a stable pre-emulsion.

[0012] Mix 10-20% of the emulsifier with water, heat and stir, then add 80-90% of the initiator and 10-20% of the mixed monomers in sequence. After the reaction is complete, the seed emulsion is obtained.

[0013] Add 10-20% initiator and seed emulsion to the pre-emulsion and heat to react, thus obtaining an acrylate emulsion.

[0014] By adjusting the order of addition of each component, using an emulsifier to pre-emulsify most of the monomer raw materials first, then emulsifying a small portion of the raw material monomers, and then mixing and reacting, the resulting acrylic emulsion has high film density and features high hardness and high stain resistance.

[0015] More preferably, the emulsifier is composed of sodium dioctyl sulfosuccinate and emulsifier MOA-7 in a weight ratio of 1:(0.5-1).

[0016] The film-forming process of an emulsion involves the mutual compression of latex particles. The particle size significantly affects the film density; smaller particle sizes result in higher film density and improved anti-fouling properties. Sodium dioctyl sulfosuccinate and emulsifier MOA-7 are combined as emulsifiers to synergistically stabilize the emulsion. Sodium dioctyl sulfosuccinate stabilizes the latex particles through electrostatic repulsion, while emulsifier MOA-7 stabilizes them through steric hindrance, improving the particle size distribution and resulting in a denser film.

[0017] More preferably, the raw materials in the acrylate emulsion are in the following weight proportions: methyl methacrylate 50-100 parts, n-butyl acrylate 25-50 parts, isooctyl acrylate 25-50 parts, methacrylic acid 5-10 parts, triethoxysilane succinic anhydride 5-10 parts, diacetone acrylamide 1-3 parts, dihydrazine adipic acid 1-3 parts, emulsifier 5-10 parts, initiator 1-3 parts, and water 100 parts.

[0018] More preferably, the titanium dioxide is nano-rutile titanium dioxide.

[0019] The use of nano-grade rutile titanium dioxide can improve the absorption capacity of ceramic paint to ultraviolet light, increase the density of the paint film, and greatly improve the scrub resistance and mechanical strength of the coating.

[0020] More preferably, the filler is one or a combination of two of nano-silica, talc, wollastonite, and mica powder.

[0021] More preferably, the defoamer is one or a combination of two or more of the following: mineral oil-based defoamer, organosilicon defoamer, and nonionic defoamer.

[0022] More preferably, the thickener is one or a combination of two or more of hydroxyethyl cellulose, thickener TT-935, and bentonite.

[0023] More preferably, the dispersant is one or a combination of two or more of acrylate, polyurethane, and sodium polyphosphate.

[0024] Secondly, this application provides a method for preparing a stain-resistant, high-hardness nano-ceramic paint, using the following technical solution:

[0025] A method for preparing a stain-resistant, high-hardness nano-ceramic paint includes the following preparation steps:

[0026] Add film-forming aid, dispersant, defoamer, and thickener to water, stir and disperse evenly. Then add acrylate emulsion and nano-inorganic silicone resin, stir and disperse evenly. Next, add titanium dioxide and filler, stir and disperse evenly. Finally, add formaldehyde removal aid, stir and disperse evenly to obtain the final product.

[0027] In summary, this application has the following beneficial effects:

[0028] Enhanced stain resistance and self-cleaning ability: This application provides an acrylic emulsion prepared using a stepwise polymerization process of pre-emulsification and seed emulsion. Combined with sodium sulfosuccinate and MOA-7 compound emulsifier, it significantly improves the latex particle size distribution, resulting in a low porosity film that effectively blocks contaminant penetration. The introduction of nano-inorganic silicone resin and triethoxysilane succinic anhydride creates a low surface energy siloxane network on the coating surface, imparting hydrophobic and oleophobic properties. Stains are difficult to adhere to and easy to clean.

[0029] Synergistic Enhancement of High Hardness and Flexibility: Through the molecular structure design of the acrylic emulsion, a precise ratio of methyl methacrylate (hard monomer) to n-butyl acrylate and isooctyl acrylate (soft monomer), combined with a dual crosslinking system (ketone-hydrazine crosslinking + silane coupling), effectively balances the rigidity and flexibility of the coating film. The hard monomer imparts high hardness and abrasion resistance to the coating, while the soft monomer improves adhesion and impact resistance. The dual crosslinking system further enhances the density of the coating film, ultimately achieving a film hardness of 3H or higher.

[0030] Wide range of applications: This porcelain paint combines high hardness, stain resistance, environmental friendliness and decorative properties, and can be widely used in building exterior walls, interior walls, metal protection, wooden furniture and automotive parts, etc. It is especially suitable for children's room decoration and can deal with scenes of graffiti. Detailed Implementation

[0031] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application.

[0032] Furthermore, it should be understood that the one or more method steps mentioned in this application do not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, unless otherwise stated. Moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and is not intended to limit the order of the method steps or limit the scope of implementation of this application. Changes or adjustments to their relative relationships, without substantially altering the technical content, shall also be considered as within the scope of implementation of this application.

[0033] Unless otherwise specified, the experimental conditions used in the examples are generally in accordance with conventional conditions in the art or the conditions recommended by the reagent company. Unless otherwise specified, the materials and reagents used in the examples can be purchased commercially.

[0034] The raw materials used in this application are sourced as follows: the nano-inorganic silicone resin used is water-based nano-inorganic silicone resin BS-518, purchased from Jinan Baishiduo Polymer Chemical Technology Co., Ltd.; the formaldehyde removal additive is Rhodoline. ® FS360 formaldehyde absorption aid was purchased from Nanjing Qinhai Trading Co., Ltd. Sodium dioctyl sulfosuccinate was purchased from Wuhan Kanos Technology Co., Ltd.; MOA-7 emulsifier was purchased from Nantong Dexin Chemical Co., Ltd.; nano silica was purchased from Suzhou Qiuyi New Materials; and dimethyl silicone oil defoamer was purchased from Huangshan Qiangli Chemical Co., Ltd.

[0035] In this application, the triethoxysilane succinic anhydride can be customized or prepared in-house. The preparation steps are as follows: 44.95g of allyltriethoxysilane and 19.61g of maleic anhydride are added to a 250mL flask as reactants, 0.47g of hydroquinone is added as a polymerization inhibitor, and 5.77g of methanesulfonic acid is added as a catalyst. The reaction temperature is set to 180℃, and after reacting for 6 hours, the mixture is cooled to room temperature. 100mL of petroleum ether and 10g of kaolin are added, and the mixture is stirred for 10 minutes and then filtered. The filtrate is concentrated by rotary evaporation, and the residue is distilled under reduced pressure at 9mmHg and 290℃ to obtain 47.22g of triethoxysilane succinic anhydride.

[0036] Preparation Example 1

[0037] Preparation of acrylate emulsions:

[0038] Raw material composition: 50 parts methyl methacrylate, 25 parts n-butyl acrylate, 25 parts isooctyl acrylate and 5 parts methacrylic acid as mixed monomers, 10 parts triethoxysilane succinic anhydride as functional monomers, 2 parts diacetone acrylamide and 2 parts dihydrazine adipate as crosslinking monomers, a mixture of 4 parts sodium dioctyl sulfosuccinate and 2 parts emulsifier MOA-7 as emulsifier, 1 part ammonium persulfate as initiator, and 100 parts water as solvent.

[0039] Preparation steps: Mix 80% of the emulsifier, functional monomer, crosslinking monomer, and water, heat to 50°C and stir, while adding 80% of the mixed monomer, and continue stirring until a stable pre-emulsion is obtained; mix 20% of the emulsifier with water, heat to 50°C and stir, then add 80% of the initiator and 20% of the mixed monomer successively, and after the reaction is complete, a seed emulsion is obtained; add 20% of the initiator and the seed emulsion to the pre-emulsion, heat to 95°C and react, and after the reaction is complete, an acrylate emulsion is obtained, with a solid content of 46.5%.

[0040] Preparation Example 2

[0041] Preparation of acrylate emulsions:

[0042] The amount of raw materials and the preparation method are the same as in Preparation Example 1. The difference from Preparation Example 1 is that the emulsifier is composed of 3.5 parts of sodium dioctyl sulfosuccinate and 2.5 parts of emulsifier MOA-7.

[0043] Preparation Example 3

[0044] Preparation of acrylate emulsions:

[0045] The amount of raw materials and the preparation method are the same as in Preparation Example 1. The difference from Preparation Example 1 is that the emulsifier is composed of 3 parts of sodium dioctyl sulfosuccinate and 3 parts of emulsifier MOA-7.

[0046] Comparative Preparation Example 1

[0047] Preparation of acrylate emulsions:

[0048] The amount of raw materials and the preparation method are the same as in Preparation Example 1. The difference from Preparation Example 1 is that the emulsifier used is 6 parts of sodium dioctyl sulfosuccinate.

[0049] Comparative Preparation Example 2

[0050] Preparation of acrylate emulsions:

[0051] The amount of raw materials and the preparation method are the same as in Preparation Example 1. The difference from Preparation Example 1 is that 6 parts of emulsifier MOA-7 are used.

[0052] Comparative preparation example 3

[0053] Preparation of acrylate emulsions:

[0054] The amount of raw materials and the preparation method are the same as in Preparation Example 1. The difference from Preparation Example 1 is that vinyltriethoxysilane is used instead of triethoxysilane succinic anhydride as a functional monomer in the preparation of acrylate emulsion.

[0055] Example

[0056] Example 1

[0057] Preparation of anti-fouling, high-hardness nano-ceramic paint:

[0058] Using the acrylate emulsion obtained in Preparation Example 1 and the waterborne nano-inorganic silicone resin BS-518 as the film-forming system, dodecyl alcohol ester as the film-forming aid, nano-silica as the filler, dimethyl silicone oil as the defoamer, sodium hexametaphosphate as the dispersant, and hydroxyethyl cellulose as the thickener, a ceramic coating was prepared. The specific amounts of each raw material are shown in Table 1.

[0059] Preparation steps: Add film-forming aid, dispersant, defoamer, and thickener to water, stir and disperse evenly, then add acrylate emulsion and nano-inorganic silicone resin, stir and disperse evenly, then add titanium dioxide and filler, stir and disperse evenly, and finally add formaldehyde removal aid, stir and disperse evenly to obtain the final product.

[0060] Example 2-3

[0061] Preparation of anti-fouling high-hardness nano-ceramic paint: The amount of raw materials is shown in Table 1, and the preparation method is the same as in Example 1.

[0062] Table 1. Amounts of raw material components used in Examples 1-3

[0063]

[0064] Example 4

[0065] Preparation of anti-fouling high-hardness nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion is prepared in Example 2.

[0066] Example 5

[0067] Preparation of anti-fouling high-hardness nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion is prepared in Example 3.

[0068] Comparative Example

[0069] Comparative Example 1

[0070] Preparation of nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion was prepared by comparative preparation example 1.

[0071] Comparative Example 2

[0072] Preparation of nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion was prepared by comparative preparation example 2.

[0073] Comparative Example 3

[0074] Preparation of nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion was prepared by comparative preparation example 3.

[0075] Comparative Example 4

[0076] Preparation of nano-ceramic paint: The amount of raw materials and the preparation method are the same as in Example 1. The difference from Example 1 is that the acrylic emulsion was purchased from Dow Chemical, model PRIMAL TR407.

[0077] Performance testing

[0078] Comparative tests were conducted on the stain resistance, scrub resistance and hardness of the porcelain paints prepared in Examples 1-5 and Comparative Examples 1-4. The specific test standards are as follows, and the test results are shown in Table 2.

[0079] Stain resistance: Film preparation, curing, and washing were conducted according to GB / T 9780—2013 "Test Method for Stain Resistance of Architectural Coatings". The overall stain resistance ΔE was used as the evaluation index, where ΔE = ΔL, Δa, and Δb represent the differences in L (brightness value), a (red-green value), and b (yellow-blue value) before and after wiping, respectively. The smaller ΔE is, the closer the color of the stained area is to the uncolored blank film, meaning the stronger the stain resistance.

[0080] Scrub resistance: Tested in accordance with GB / T 9756-2018 Synthetic resin emulsion interior wall coatings.

[0081] Hardness: The hardness of the paint film was tested according to GB / T 6739-2022, "Determination of Hardness of Paint and Varnish Film by Pencil Method".

[0082] Table 2 Test Results

[0083]

[0084] As can be seen from Table 2, the ceramic paint prepared in this application has excellent stain resistance, scrub resistance, and high hardness.

[0085] Comparing the test results of Example 1 and Comparative Examples 1-2, it can be seen that the selection and dosage of emulsifier have a significant impact on the performance of the final coating. The acrylic emulsion prepared by using sodium dioctyl sulfosuccinate and MOA-7 as a compound emulsifier has high anti-fouling properties and hardness. This is because the emulsifier mainly controls the particle size and distribution of latex particles. The compound emulsifier of this application can obtain an emulsion with uniform particle size distribution, thereby improving the film density.

[0086] Comparing the test results of Example 1 and Comparative Example 3, it can be seen that using triethoxysilane succinic anhydride as the functional monomer is more effective than using vinyltriethoxy. This is because the anhydride in triethoxysilane can participate in the emulsion crosslinking reaction and the subsequent coating film-forming crosslinking reaction. The siloxane group is also easy to react with inorganic substances, which improves the bonding force. In addition, the triethoxysilane succinic anhydride of this application is prepared from allyltriethoxysilane and maleic anhydride, and the chain length is relatively longer. Therefore, the toughness of the resulting coating is better than that of vinylsilane coupling agent. The coatings prepared by the two were tested for impact resistance separately. The test results showed that the impact resistance was 42 cm in Example 1 and 31 cm in Comparative Example 3, respectively. It can be seen that the coating prepared by this application has higher toughness.

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A stain-resistant, high-hardness nano-ceramic paint, characterized in that, The product comprises the following components in parts by weight: 90-120 parts acrylate emulsion, 40-60 parts nano-inorganic silicone resin, 5-10 parts film-forming aid, 20-30 parts titanium dioxide, 10-20 parts filler, 0.5-2 parts formaldehyde removal aid, 2-3 parts dispersant, 0.5-1.5 parts defoamer, 1-2 parts thickener, and 10-20 parts water. The acrylate emulsion has a solid content of 46-48% and is made from the following raw materials: methyl methacrylate, n-butyl acrylate, a mixed monomer composed of isooctyl acrylate and methacrylic acid, a functional monomer composed of triethoxysilane succinic anhydride, a crosslinking monomer composed of diacetone acrylamide and dihydrazine adipate, an emulsifier, an initiator, and water.

2. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The acrylate emulsion was prepared by the following steps: Mix 80-90% of the emulsifier, functional monomer, crosslinking monomer with water, heat and stir, and simultaneously add 80-90% of the mixed monomers to obtain a stable pre-emulsion. Mix 10-20% of the emulsifier with water, heat and stir, then add 80-90% of the initiator and 10-20% of the mixed monomers in sequence. After the reaction is complete, the seed emulsion is obtained. Add 10-20% initiator and seed emulsion to the pre-emulsion and heat to react, thus obtaining an acrylate emulsion.

3. The anti-fouling, high-hardness nano-ceramic paint according to claim 2, characterized in that, The emulsifier is composed of sodium dioctyl sulfosuccinate and emulsifier MOA-7 in a weight ratio of 1:(0.5-1).

4. The anti-fouling, high-hardness nano-ceramic paint according to claim 3, characterized in that, The raw materials in the acrylate emulsion are in the following weight proportions: methyl methacrylate 50-100 parts, n-butyl acrylate 25-50 parts, isooctyl acrylate 25-50 parts, methacrylic acid 5-10 parts, triethoxysilane succinic anhydride 5-10 parts, diacetone acrylamide 1-3 parts, dihydrazine adipic acid 1-3 parts, emulsifier 5-10 parts, initiator 1-3 parts, and water 100 parts.

5. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The titanium dioxide used is nano-rutile titanium dioxide.

6. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The filler is one or a combination of two of the following: nano-silica, talc, wollastonite, and mica powder.

7. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The dispersant is one or a combination of two or more of acrylate, polyurethane, and sodium polyphosphate.

8. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The defoamer is one or a combination of two or more of the following: mineral oil-based defoamers, organosilicon defoamers, and nonionic defoamers.

9. The anti-fouling, high-hardness nano-ceramic paint according to claim 1, characterized in that, The thickener is one or a combination of two or more of hydroxyethyl cellulose, thickener TT-935, and bentonite.

10. A method for preparing a stain-resistant, high-hardness nano-ceramic paint according to any one of claims 1-9, characterized in that, The preparation steps include the following: Add film-forming aid, dispersant, defoamer, and thickener to water, stir and disperse evenly. Then add acrylate emulsion and nano-inorganic silicone resin, stir and disperse evenly. Next, add titanium dioxide and filler, stir and disperse evenly. Finally, add formaldehyde removal aid, stir and disperse evenly to obtain the final product.

Images