A kind of water-based self-matting acrylic resin and preparation method thereof

Abstract

The present application relates to a kind of water-based self-matting acrylic resin and preparation method thereof, relate to the technical field of functional polymer materials, the water-based self-matting acrylic resin of the present application includes fine-particle size emulsion and coarse-particle size emulsion, and fine-particle size emulsion and coarse-particle size emulsion are both acrylic emulsions;The particle diameter of fine-particle size emulsion is 20 90nm;The particle diameter of coarse-particle size emulsion is 2 5μm;The mass ratio of fine-particle size emulsion and coarse-particle size pure emulsion is 1: 1 2.During the film formation of the present application, fine-particle size emulsion forms a dense emulsion film as a microscopic continuous phase, which is closely stacked with coarse-particle size latex particles, and polymer chains diffuse and entangle at the interface of original latex particles, and particles fuse to form an uneven film, achieving matting effect. The fine-particle size emulsion and coarse-particle size emulsion used in the present application are acrylic emulsions, and components are similar, with excellent compatibility, and retain the high water resistance, wear resistance and high hardness performance of acrylic resin.

Description

Technical Field

[0001] The present application relates to the technical field of functional polymer materials, and in particular to a water-based self-matting acrylic resin and a preparation method thereof. Background Art

[0002] In daily life, items with matte effects can be seen everywhere. When choosing whether an item has a glossy or matte effect, we should not only consider fashion and appearance, but also easy cleaning, brightness, touch, safety, economy and practicality.

[0003] Currently, matting technologies are primarily categorized into physical and chemical matting. Physical matting involves adding a matting agent to a base resin to create a matte coating. Examples include naturally occurring high-density fillers, micro-wax powders, inorganic matting powders, and organic matting resin fillers. Nano-fumed SiO2 matting powder is the most commonly used matting agent on the market. While this matting agent-added method can achieve matting, it also has significant drawbacks: For example, the addition of matting agents alters the coating's rheological properties; the composition can coagulate, resulting in a seed-like appearance; the coating becomes more brittle and prone to breakage and shedding; matting agents easily precipitate, causing variations in gloss across the coating; and resistance to rubbing, bending, and friction is reduced.

[0004] In contrast, chemical matting resins offer incomparable advantages. First, chemical matting exploits the difference in curing temperature between the functional groups in the matting resin and the curing agent in the coating composition, resulting in sequential curing and uneven shrinkage of the coating film, which in turn affects the smoothness of the coating and causes matting. Second, it increases the surface tension difference between the two resins, causing uneven shrinkage and micro-roughness. Third, by introducing incompatible monomers into the synthetic resin, these monomers cause the synthetic resin to precipitate from the center of the coating during film formation, increasing the micro-roughness of the coating surface and achieving a low gloss. Therefore, chemical matting technology not only avoids the aforementioned drawbacks associated with the addition of matting agents, but also streamlines the construction process and reduces the cost of purchasing matting agents.

[0005] Water-based acrylic resins are the primary type of water-based coatings. Because the C-C bonds in their backbone chains are resistant to oxidation and hydrolysis, acrylic resins exhibit excellent antioxidant and dielectric properties. Furthermore, their primary electromagnetic absorption peak falls outside the solar spectrum, resulting in excellent outdoor weather resistance. Furthermore, acrylic resin emulsions offer advantages such as simple production processes, safety, environmental friendliness, and low cost. Consequently, they have been widely used in leather finishing, textile coatings, interior and exterior wall coatings, adhesives, papermaking, automotive, construction, biotechnology, and aerospace applications.

[0006] Currently, the main acrylic resin matting agents on the market include organic fluorine-modified acrylic resins and organic silicone-modified acrylic resins. Fluorine-modified acrylic resins exhibit strong chemical inertness, excellent water, stain, and oil repellency, and good film-forming properties, flexibility, and adhesion. Fluorinated acrylate coatings exhibit low surface energy, low friction, self-cleaning properties, and excellent weather resistance. The organic silicone backbone consists of Si-O bonds and has alkyl side chains, which combine the properties of both inorganic and organic materials.

[0007] Although acrylic resins modified with silicone and organic fluorine have excellent water resistance and thermal stability, and the modified acrylic emulsions have excellent matting effects, they are expensive.

[0008] The second is water-based polyurethane emulsion, but water-based polyurethane has problems such as uneven coating, poor wettability to non-polar substrates, water pollution in wastewater, poor water resistance, etc.

[0009] Therefore, there is an urgent need to develop an acrylic resin that is environmentally friendly, highly water-resistant, wear-resistant, high hardness and has excellent matting effect. Summary of the Invention

[0010] In order to solve at least one of the above technical problems, an acrylic resin with high water resistance, wear resistance, high hardness and excellent matting effect is developed. The present application provides a water-based self-matting acrylic resin and a preparation method thereof.

[0011] In the first aspect, the water-based self-matting acrylic resin provided in this application adopts the following technical solution:

[0012] A water-based self-matting acrylic resin comprises a fine-particle emulsion and a coarse-particle emulsion, both of which are acrylic emulsions; the particle diameter of the fine-particle emulsion is 20-90 nm; the particle diameter of the coarse-particle emulsion is 2-5 μm; and the mass ratio of the fine-particle emulsion to the coarse-particle pure emulsion is 1:1-2.

[0013] By adopting the above-mentioned technical scheme, the acrylic resin designed by the present application adopts fine-particle diameter emulsion and coarse-particle diameter emulsion. When film-forming, the fine-particle diameter emulsion forms a dense emulsion film as a microscopic continuous phase, and is gradually closely stacked with coarse-particle diameter latex particles. Polymer chains diffuse and entangle with each other at the original latex particle interface, and particles merge with each other, so that an uneven structural polymer film can be formed to achieve a matte effect. And adopt a specific ratio, the latex particles of different particle sizes interpenetrate each other, so that the gap between the latex particles disappears, until capillaries are formed, and then the particle interface disappears, forming an uneven polymer film, realizing that the emulsion performance of different particle sizes complements each other, and the matte effect is excellent. The fine-particle diameter emulsion and coarse-particle diameter emulsion adopted by the present application are both acrylic emulsions, and the components are similar, so there is excellent compatibility, and the original high water resistance, wear resistance and high hardness of acrylic resin are retained.

[0014] Optionally, the raw materials of the fine particle size emulsion include the following components in parts by weight: 60-100 parts of monomer; 0.2-0.5 parts of initiator; 2-4 parts of emulsifier A; 1-2 parts of crosslinking agent; 0.2-0.5 parts of buffer; and 110-180 parts of deionized water.

[0015] Optionally, the raw materials of the coarse particle size emulsion include the following components in parts by weight: 50-80 parts of monomer; 0.1-0.2 parts of initiator; 0.5-1.2 parts of emulsifier B; 0.5-1 parts of cross-linking agent; 0.2-0.5 parts of buffer; and 60-100 parts of deionized water.

[0016] Optionally, the monomer includes one or more of acrylic acid, methacrylic acid, methyl methacrylate, methyl acrylate, ethyl acrylate, and butyl acrylate; the initiator is ammonium persulfate; the crosslinker is N-hydroxyacrylamide; and the emulsifier is a mixed solution of an anionic emulsifier and a nonionic emulsifier.

[0017] By adopting the above technical solution, the monomers selected are one or more of acrylic acid, methacrylic acid, methyl methacrylate, methyl acrylate, and ethyl acrylate, which are similar in composition and have excellent compatibility. The present application adopts a compound of anionic emulsifier and nonionic emulsifier, which overcomes the shortcomings of poor chemical stability of anionic emulsifier and weak emulsification ability, poor mechanical stability, and easy demulsification of nonionic emulsifier. The two emulsifiers work synergistically, and the emulsifier molecules alternately adsorb on the surface of the latex particles, reducing the charge density on the surface of the latex particles, making it easier for negatively charged free radicals to enter the latex particles, and improving the degree of emulsion polymerization; and the nonionic emulsifier is adsorbed on the surface of the particles to form an elastic interface film, which prevents the particles from coagulating and improves the performance of the resulting emulsion.

[0018] Optionally, the anionic emulsifier is one or both of sodium didodecylphenyl ether disulfonate and sodium laurate; and the nonionic emulsifier is one or both of polyoxyethylene ether and ethylene oxide.

[0019] Optionally, the ratio of the anionic emulsifier to the nonionic emulsifier in the emulsifier A is 3-4:1; the ratio of the anionic emulsifier to the nonionic emulsifier in the emulsifier B is 1-2:1.

[0020] By adopting the above technical solution, emulsifier A and emulsifier B are used in a specific ratio to prepare the fine particle size and coarse particle size acrylic emulsions required for this application. In addition, acrylic resins with specific properties can be prepared according to the requirements of acrylic resins.

[0021] In a second aspect, the present application provides a method for preparing a water-based self-matting acrylic resin using the following technical solution: mixing and stirring a fine-particle emulsion and a coarse-particle emulsion, and obtaining a matte acrylic resin after the reaction is completed;

[0022] The preparation process of the fine particle size emulsion comprises the following steps:

[0023] S1: Pre-emulsification: Add monomers and 3 / 5 emulsifier A, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion;

[0024] S2: Seed emulsion: Add 2 / 5 emulsifier A, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 3 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion;

[0025] S3: Polymerization: slowly add the remaining 7 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge.

[0026] The preparation process of the coarse particle size emulsion comprises the following steps:

[0027] S4: Pre-emulsification: Add monomers and 3 / 5 emulsifier B, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion;

[0028] S5: Seed emulsion: Add 2 / 5 emulsifier B, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 1 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion;

[0029] S6: Discharging: slowly add the remaining 9 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge.

[0030] By adopting the above technical solution, the preparation process of the present application is simple, flexible, and easy to produce. In addition, the present application adopts a specific process design. By adjusting the ratio of the emulsifier and controlling the particle size range of the acrylic emulsion, an acrylic emulsion that meets specific needs can be prepared according to product requirements.

[0031] Optionally, the stirring rate is 300-500 r / min; the temperature in S2 is raised to 75-85° C.; and the temperature in S5 is raised to 80-85° C.

[0032] By adopting the above technical solution, the acrylic emulsion has a good dispersion effect. When the temperature in S2 is raised to 75-85°C, the monomer conversion rate of the fine-particle acrylic emulsion prepared is optimal. When the temperature in S5 is raised to 80-85°C, the monomer conversion rate of the coarse-particle acrylic emulsion prepared is optimal.

[0033] In a third aspect, the present application provides an application of a water-based self-matting acrylic resin in the field of poly-ε-caprolactone substrate coating.

[0034] By adopting the above technical solution and using chemical matting to prepare the water-based acrylic resin, a good anti-adhesion effect can be achieved.

[0035] In summary, this application includes at least one of the following beneficial technical effects:

[0036] 1. The fine-particle acrylic emulsion and coarse-particle acrylic emulsion designed in this application form a dense emulsion film as a microscopic continuous phase, gradually and closely stacking with the coarse-particle latex particles. Polymer chains diffuse and entangle at the interfaces of the original latex particles, and the particles fuse together, forming a rugged structured polymer film, achieving a matte effect. Since both the fine-particle and coarse-particle acrylic emulsions have similar components, they have excellent compatibility and retain the inherent high water resistance, wear resistance, and hardness of the acrylic resin.

[0037] 2. This application uses a combination of anionic and nonionic emulsifiers. The two emulsifiers work synergistically, with the emulsifier molecules alternately adsorbing on the surface of the latex particles, reducing the charge density on the surface of the latex particles, making it easier for negatively charged free radicals to enter the latex particles, and improving the degree of emulsion polymerization. The nonionic emulsifier is adsorbed on the particle surface to form an elastic interfacial film, which prevents the particles from coagulating and improves the performance of the resulting emulsion.

[0038] 3. The preparation method of the present application is simple, low-cost, flexible, and easy to produce. Furthermore, the present application adopts a specific process design. By adjusting the ratio of the emulsifier and controlling the particle size range of the acrylic emulsion, an acrylic emulsion that meets specific product requirements can be prepared.

[0039] 4. The water-based acrylic resin prepared in this application is safe and environmentally friendly;

[0040] 5. The application of the water-based acrylic resin prepared in the present application in the field of poly-ε-caprolactone substrate coating has excellent anti-adhesion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic diagram of the film formation of the water-based self-matting acrylic resin of the present application. DETAILED DESCRIPTION

[0042] The following is combined with Figure 1 The present application is further described in detail with reference to the accompanying drawings and embodiments.

[0043] The water-based self-matting acrylic resin designed in this application includes a fine-particle emulsion and a coarse-particle emulsion, both of which are acrylic emulsions; the particle diameter of the fine-particle emulsion is 20-90 nm; the particle diameter of the coarse-particle emulsion is 2-5 μm; the mass ratio of the fine-particle emulsion to the coarse-particle pure emulsion is 1:1-2.

[0044] The preparation method of the water-based self-matting acrylic resin of the present application comprises the following preparation steps:

[0045] The fine particle size emulsion and the coarse particle size emulsion are mixed and stirred, and after the reaction is completed, a matte acrylic resin is obtained;

[0046] The preparation process of the fine particle size emulsion comprises the following steps:

[0047] S1: Pre-emulsification: Add monomers and 3 / 5 emulsifier A, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion;

[0048] S2: Seed emulsion: Add 2 / 5 emulsifier A, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 3 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion;

[0049] S3: Polymerization: slowly add the remaining 7 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge.

[0050] The preparation process of the coarse particle size emulsion comprises the following steps:

[0051] S4: Pre-emulsification: Add monomers and 3 / 5 emulsifier B, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion;

[0052] S5: Seed emulsion: Add 2 / 5 emulsifier B, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 1 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion;

[0053] S6: Discharging: slowly add the remaining 9 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge.

[0054] Prior to this application, physical matting was commonly used, but this method is prone to poor dispersion and reduced overall film mechanical strength due to film formation defects. Furthermore, existing matting coatings primarily use water-based polyurethane emulsions, but these suffer from issues such as uneven coating, poor wettability on non-polar substrates, water contamination in wastewater, poor water resistance, and high cost. Acrylic resin emulsions offer advantages such as simple production processes, safety, environmental protection, and low cost, but there are relatively few patents on self-matting water-based acrylic emulsions.

[0055] In view of the above problems, the inventors of this application designed the technical solution of this application. Through special formula design and corresponding preparation method, the water-based self-matting acrylic resin of this application was prepared, which has high water resistance, wear resistance, high hardness and excellent matting effect.

[0056] The inventors of this application designed an acrylic emulsion system with different latex particle sizes and a specific ratio, such as Figure 1 As shown, latex particles of varying sizes interpenetrate, eliminating gaps between particles until capillaries form, leading to the disappearance of particle interfaces. Polymer chains diffuse and entangle at the interfaces of the original latex particles, fusing the particles together to form a rugged polymer film, achieving complementary performance between latexes of varying particle sizes. Furthermore, considering the compatibility of the components, the same acrylic emulsion was used, preserving the inherent high water resistance, abrasion resistance, and hardness of the acrylic resin.

[0057] Secondly, this application utilizes a combination of anionic and nonionic emulsifiers. The two emulsifiers work synergistically, with the emulsifier molecules alternately adsorbing on the surface of the latex particles, reducing the surface charge density, allowing negatively charged free radicals to more easily enter the particles, and increasing the degree of emulsion polymerization. Furthermore, the nonionic emulsifier is adsorbed on the particle surface, forming an elastic interfacial film that prevents particle coagulation and improves the performance of the resulting emulsion. Furthermore, by adjusting the ratio of the emulsifiers, and thereby controlling the particle size of the acrylic emulsion, an acrylic emulsion that meets specific product requirements can be prepared.

[0058] The raw materials used in the preparation examples and examples of this application can be obtained from commercial sources, among which:

[0059] Acrylic acid, methacrylic acid, methyl methacrylate, ethyl acrylate, methyl acrylate: Jiangsu Jurong Chemical Co., Ltd.

[0060] Sodium didodecylphenyl ether disulfonate, sodium laurate: Xingtai Xinlanxing Technology Co., Ltd.

[0061] Polyoxyethylene ether, ethylene oxide: Xingtai Xinlanxing Technology Co., Ltd.

[0062] Ammonium persulfate: Nanfeng Fine Chemicals.

[0063] N-hydroxyacrylamide: Mingzhixin Chemical.

[0064] Preparation Example 1

[0065] Add 60 kg of acrylic acid, 1 kg of sodium didodecylphenyl ether disulfonate, and 0.2 kg of polyoxyethylene ether, mix, heat and dissolve, and stir for 40 minutes to obtain 62 kg of pre-emulsion;

[0066] 0.5 kg of sodium didodecylphenyl ether disulfonate, 0.3 kg of polyoxyethylene ether emulsifier, 0.2 kg of buffer and 110 kg of deionized water were added, mixed and heated to dissolve, 0.08 kg of ammonium persulfate was added, the temperature was raised, and 18.6 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 18.68 kg of seed emulsion;

[0067] 43.4 kg of pre-emulsion, 0.12 kg of ammonium persulfate and 1 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0068] Preparation Example 2

[0069] Add 30 kg of methacrylic acid, 40 kg of methyl methacrylate, 1 kg of sodium didodecylphenyl ether disulfonate, 0.5 kg of sodium laurate, and 0.4 kg of polyoxyethylene ether, mix, heat and dissolve, and stir for 40 minutes to obtain 73 kg of pre-emulsion;

[0070] 0.5 kg of sodium didodecylphenyl ether disulfonate, 0.3 kg of sodium laurate, 0.3 kg of polyoxyethylene ether emulsifier, 0.2 kg of buffer and 130 kg of deionized water were added, mixed and heated to dissolve, 0.12 kg of ammonium persulfate was added, the temperature was raised, and 21.9 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 22.02 kg of seed emulsion;

[0071] 51.1 kg of pre-emulsion, 0.18 kg of ammonium persulfate and 1.2 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0072] Preparation Example 3

[0073] 30 kg of acrylic acid, 30 kg of methacrylic acid, 0.7 kg of sodium didodecylphenyl ether disulfonate, 1 kg of sodium laurate, 0.3 kg of polyoxyethylene ether, and 0.2 kg of ethylene oxide were added, mixed, heated, and dissolved, and stirred for 40 minutes to obtain 83.5 kg of pre-emulsion;

[0074] 0.3 kg of sodium didodecylphenyl ether disulfonate, 0.7 kg of sodium laurate, 0.1 kg of polyoxyethylene ether, 0.2 kg of ethylene oxide, 0.2 kg of buffer, and 145 kg of deionized water were added, mixed, heated, and dissolved. 0.16 kg of ammonium persulfate was added, the temperature was raised, and 25.05 kg of pre-emulsion was added. The mixture was stirred for 20 minutes to prepare 25.21 kg of seed emulsion.

[0075] 58.45 kg of pre-emulsion, 0.24 kg of ammonium persulfate and 1.4 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0076] Preparation Example 4

[0077] 30 kg of methacrylic acid, 20 kg of methyl acrylate, 40 kg of ethyl acrylate, 2 kg of sodium laurate, 0.2 kg of polyoxyethylene ether and 0.3 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 94 kg of pre-emulsion;

[0078] 1.1 kg of sodium laurate, 0.2 kg of polyoxyethylene ether, 0.2 kg of ethylene oxide, 0.2 kg of buffer and 160 kg of deionized water were added, mixed and heated to dissolve, 0.2 kg of ammonium persulfate was added, the temperature was raised, and 28.2 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 28.4 kg of seed emulsion;

[0079] 65.8 kg of pre-emulsion, 0.3 kg of ammonium persulfate and 1.6 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0080] Preparation Example 5

[0081] 60 kg of methyl acrylate, 40 kg of ethyl acrylate, 1.9 kg of sodium laurate and 0.4 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 103 kg of pre-emulsion;

[0082] 0.5 kg of sodium laurate, 0.2 kg of ethylene oxide, 0.2 kg of buffer, and 160 kg of deionized water were added, mixed and heated to dissolve, 0.12 kg of ammonium persulfate was added, the temperature was raised, and 30.9 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 31.02 kg of seed emulsion;

[0083] 72.1 kg of pre-emulsion, 0.18 kg of ammonium persulfate and 1.8 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0084] Preparation Example 6

[0085] 80 kg of acrylic acid, 1.8 kg of sodium laurate and 0.4 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 83 kg of pre-emulsion;

[0086] 0.8 kg of sodium laurate, 0.2 kg of ethylene oxide, 0.2 kg of buffer, and 145 kg of deionized water were added, mixed and heated to dissolve, 0.16 kg of ammonium persulfate was added, the temperature was raised, and 24.9 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 25.06 kg of seed emulsion;

[0087] 58.1 kg of pre-emulsion, 0.24 kg of ammonium persulfate and 2 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a fine particle size emulsion.

[0088] Preparation Example 7

[0089] 15 kg of acrylic acid, 0.25 kg of sodium laurate and 0.25 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 15.5 kg of pre-emulsion;

[0090] 0.05 kg of sodium laurate, 0.05 kg of ethylene oxide, 0.1 kg of buffer, and 60 kg of deionized water were added, mixed and heated to dissolve, 0.02 kg of ammonium persulfate was added, the temperature was raised, and 1.55 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 1.57 kg of seed emulsion;

[0091] 13.95 kg of pre-emulsion, 0.08 kg of ammonium persulfate and 0.5 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a coarse particle size emulsion.

[0092] Preparation Example 8

[0093] 8 kg of methacrylic acid, 10 kg of methyl methacrylate, 0.3 kg of sodium didodecylphenyl ether disulfonate, 0.15 kg of polyoxyethylene ether, and 0.08 kg of ethylene oxide were added, mixed, heated, and dissolved, and stirred for 40 minutes to obtain 18.7 kg of pre-emulsion;

[0094] 0.1 kg of sodium didodecylphenyl ether disulfonate, 0.05 kg of polyoxyethylene ether, 0.02 kg of ethylene oxide, 0.1 kg of buffer, and 72 kg of deionized water were added, mixed and heated to dissolve, 0.03 kg of ammonium persulfate was added, the temperature was raised, and 1.87 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 1.9 kg of seed emulsion;

[0095] 16.83 kg of pre-emulsion, 0.12 kg of ammonium persulfate and 0.6 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a coarse particle size emulsion.

[0096] Preparation Example 9

[0097] 10 kg of acrylic acid, 5 kg of methacrylic acid, 0.3 kg of sodium laurate, 0.15 kg of polyoxyethylene ether and 0.15 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 20.9 kg of pre-emulsion;

[0098] 0.2 kg of sodium laurate, 0.05 kg of polyoxyethylene ether, 0.05 kg of ethylene oxide, 0.1 kg of buffer and 80 kg of deionized water were added, mixed and heated to dissolve, 0.04 kg of ammonium persulfate was added, the temperature was raised, and 2.09 kg of pre-emulsion was added, and stirred for 20 minutes to prepare 2.31 kg of seed emulsion;

[0099] 18.81 kg of pre-emulsion, 0.16 kg of ammonium persulfate and 0.8 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a coarse particle size emulsion.

[0100] Preparation Example 10

[0101] 22 kg of acrylic acid, 0.2 kg of sodium didodecylphenyl ether disulfonate, 0.2 kg of sodium laurate, 0.15 kg of polyoxyethylene ether and 0.15 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 23 kg of pre-emulsion;

[0102] 0.1 kg sodium didodecylphenyl ether disulfonate, 0.1 kg sodium laurate, 0.05 kg polyoxyethylene ether, 0.05 kg ethylene oxide, 0.1 kg buffer, and 88 kg deionized water were added, mixed, heated, and dissolved. 0.04 kg ammonium persulfate was added, the temperature was raised, and 2.3 kg pre-emulsion was added. The mixture was stirred for 20 minutes to prepare 2.34 kg seed emulsion.

[0103] 20.7 kg of pre-emulsion, 0.16 kg of ammonium persulfate and 0.9 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a coarse particle size emulsion.

[0104] Preparation Example 11

[0105] 15 kg of methyl methacrylate, 10 kg of ethyl acrylate, 0.5 kg of sodium laurate, 0.2 kg of polyoxyethylene ether and 0.08 kg of ethylene oxide were added, mixed, heated and dissolved, and stirred for 40 minutes to obtain 26.2 kg of pre-emulsion;

[0106] 0.3 kg of sodium laurate, 0.1 kg of polyoxyethylene ether, 0.02 kg of ethylene oxide, 0.1 kg of buffer, and 100 kg of deionized water were added, mixed, heated, and dissolved. 0.03 kg of ammonium persulfate was added, the temperature was raised, and 2.62 kg of pre-emulsion was added. The mixture was stirred for 20 minutes to prepare 2.65 kg of seed emulsion.

[0107] 23.58 kg of pre-emulsion, 0.12 kg of ammonium persulfate and 1 kg of N-hydroxyacrylamide were added to the prepared seed emulsion, kept warm, stirred for 3 hours, cooled to room temperature, adjusted the pH to 7-8, and discharged to obtain a coarse particle size emulsion.

[0108] Table 1 is a table of the formula components of the preparation examples 1-6 of the fine particle size emulsion of the present application; Table 2 is a table of the formula components of the preparation examples 7-11 of the coarse particle size emulsion of the present application:

[0109] Table 1: Formula components of fine particle size emulsion preparation examples 1-6

[0110]

[0111] Table 2: Formula components of coarse particle size emulsion preparation examples 7-11

[0112]

[0113] Example 1

[0114] The fine particle size emulsion prepared in Preparation Example 1 and the coarse particle size emulsion prepared in Preparation Example 7 were mixed and stirred, and after the reaction was completed, a matte acrylic resin was obtained.

[0115] The difference between Examples 2-11 and Comparative Examples 1-3 and Example 1 is that the raw material components and proportions are different. The raw material components and proportions of Examples 1-11 and Comparative Examples 1-3 are shown in Table 3.

[0116] Table 3: Ratio of raw materials for Examples 1-11 and Comparative Examples 1-3

[0117]

[0118] Comparative Example 4

[0119] The difference between this comparative example and Example 4 is that both the coarse particle size emulsion and the fine particle size emulsion are polyurethane emulsions;

[0120] Comparative Example 5

[0121] The difference between this comparative example and Example 4 is that the coarse particle size emulsion is a polyurethane emulsion and the fine particle size emulsion is an acrylic emulsion;

[0122] Comparative Example 6

[0123] The difference between this comparative example and Example 4 is that the coarse particle size emulsion is a styrene acrylic emulsion, and the fine particle size emulsion is the acrylic emulsion prepared in Preparation Example 4;

[0124] The styrene acrylic emulsion and polyurethane emulsion in Comparative Examples 4-6 were purchased from Tesco Chemical (Hubei) Co., Ltd.

[0125] Performance tests were performed on Examples 1-11 and Comparative Examples 1-6, and the testing methods were based on the following standards:

[0126] Gloss: GB / T 9754-2007; Anti-blocking: GB / T 23982-2009 Wood Coatings - Determination of Anti-blocking Properties; Abrasion Resistance: GB / T 1768-2006; Water Resistance: GB / T 1733-1993; Anti-blocking and other performance tests were conducted on the water-based self-matting acrylic resins of Examples 1-11 and Comparative Examples 1-3 applied to a poly-ε-caprolactone substrate. The test results are shown in Table 4.

[0127] Table 4 Performance test results of Examples 1-11 and Comparative Examples 1-6

[0128]

[0129]

[0130] The test data from Examples 1-11, Comparative Examples 1-6, and Table 4 demonstrate that the water-based, self-matting acrylic resins of Examples 1-11 of the present application exhibit excellent overall performance, particularly low coating film gloss, which can be rationally adjusted based on the ratio of coarse and fine particle size emulsions. Because the matting resins of the present invention are primarily acrylic acid, chemical matting is achieved by varying the emulsion particle size. Compared to the polyurethane emulsions in the comparative examples, the acrylic emulsions exhibit superior antioxidant and media resistance, and their similar composition further enhances the water resistance and abrasion resistance of the coatings.

[0131] Compared with Example 4, Example 1 and Example 11 have poor water resistance and gloss performance. The reason is that the former has a single component, and the latex particles are tightly packed during the film formation process. Water and other soluble substances are dispersed in the gaps between the latex particles. As the water further evaporates, the gaps between the latex particles become smaller and smaller, and thus an uneven structural polymer film is not formed, and the gloss is relatively high.

[0132] Preparation Example 12

[0133] The difference between this preparation example and preparation example 4 is that in the emulsifier A of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 2.5:1; the amount of sodium laurate is 2.85 kg, the amount of polyoxyethylene ether is 0.5 kg, and the amount of ethylene oxide is 0.65 kg.

[0134] Preparation Example 13

[0135] The difference between this preparation example and preparation example 4 is that in the emulsifier A of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 3:1; the sodium laurate is 3 kg, the polyoxyethylene ether is 0.45 kg, and the ethylene oxide is 0.55 kg.

[0136] Preparation Example 14

[0137] The difference between this preparation example and preparation example 4 is that in the emulsifier A of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 4:1; the amount of sodium laurate is 3.2 kg, the amount of polyoxyethylene ether is 0.36 kg, and the amount of ethylene oxide is 0.44 kg.

[0138] Preparation Example 15

[0139] The difference between this preparation example and preparation example 4 is that in the emulsifier A of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 4.5:1; the amount of sodium laurate is 3.27 kg, the amount of polyoxyethylene ether is 0.32 kg, and the amount of ethylene oxide is 0.41 kg.

[0140] Preparation Example 16

[0141] The difference between this preparation example and preparation example 4 is that in the emulsifier B of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 2:3; the amount of sodium didodecylphenyl ether disulfonate is 0.2 kg, the amount of sodium laurate is 0.2 kg, the amount of polyoxyethylene ether is 0.3 kg, and the amount of ethylene oxide is 0.3 kg.

[0142] Preparation Example 17

[0143] The difference between this preparation example and preparation example 4 is that in the emulsifier B of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 1:1; the amount of sodium didodecylphenyl ether disulfonate is 0.25 kg, the amount of sodium laurate is 0.25 kg, the amount of polyoxyethylene ether is 0.25 kg, and the amount of ethylene oxide is 0.25 kg.

[0144] Preparation Example 18

[0145] The difference between this preparation example and preparation example 4 is that in the emulsifier B of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 2:1; the amount of sodium didodecylphenyl ether disulfonate is 0.33 kg, the amount of sodium laurate is 0.33 kg, the amount of polyoxyethylene ether is 0.17 kg, and the amount of ethylene oxide is 0.17 kg.

[0146] Preparation Example 19

[0147] The difference between this preparation example and preparation example 4 is that in the emulsifier B of this preparation example, the weight ratio of the anionic emulsifier to the nonionic emulsifier is 3:1; the amount of sodium didodecylphenyl ether disulfonate is 0.375 kg, the amount of sodium laurate is 0.375 kg, the amount of polyoxyethylene ether is 0.125 kg, and the amount of ethylene oxide is 0.125 kg.

[0148] Examples 12-15

[0149] The difference from Example 4 is that the specific ratios of emulsifier A and emulsifier B in Examples 12-15 are different. The specific ratios are shown in Table 5.

[0150] Table 5: Distribution ratio of raw materials in Examples 12-15

[0151]

[0152] The acrylic resins prepared in Examples 12-15 were subjected to performance tests. The test results are shown in Table 6.

[0153] Table 6 Performance test of acrylic resin prepared in Examples 12-15

[0154]

[0155]

[0156] The data in Table 6 show that the water-based self-matting acrylic resins prepared in Examples 4 and 13-14 have excellent comprehensive properties. That is, the ratio of the anionic emulsifier to the nonionic emulsifier in the emulsifier A in the fine-particle emulsion is 3-4:1; and the ratio of the anionic emulsifier to the nonionic emulsifier in the emulsifier B in the coarse-particle emulsion is 1-2:1. The water-based self-matting acrylic resin prepared by mixing the fine-particle emulsion and the coarse-particle emulsion has better comprehensive properties.

[0157] The appropriate type and proportion of emulsifiers can make the monomer reaction in the emulsion more complete, and the particle sizes of different types of emulsifiers vary greatly. Emulsifiers with relatively larger particle sizes can further improve the matting properties of acrylic resins.

[0158] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. A water-based self-matting acrylic resin, characterized in that: The invention comprises a fine-particle emulsion and a coarse-particle emulsion, both of which are acrylic emulsions; the particle diameter of the fine-particle emulsion is 20-90 nm; the particle diameter of the coarse-particle emulsion is 2-5 μm; the mass ratio of the fine-particle emulsion to the coarse-particle emulsion is 1:1-2; the raw materials of the fine-particle emulsion include the following components in parts by weight: 60-100 parts of monomer; 0.2-0.5 parts of initiator; 2-4 parts of emulsifier A; 1-2 parts of crosslinking agent; 0.2-0.5 parts of buffer; and 110-180 parts of deionized water; the raw materials of the coarse-particle emulsion include the following components in parts by weight: 50-80 parts of monomer; 0.1-0.2 parts of initiator; emulsifier B 0.5-1.2 parts; 0.5-1 parts of cross-linking agent; 0.2-0.5 parts of buffer; 60-100 parts of deionized water; the emulsifier A and emulsifier B are a mixed solution of anionic emulsifier and nonionic emulsifier; the ratio of the anionic emulsifier and nonionic emulsifier in the emulsifier A is 3-4:1; the ratio of the anionic emulsifier and nonionic emulsifier in the emulsifier B is 1-2:1; the water-based self-matting acrylic resin forms an uneven polymer film; the monomers include one or more of acrylic acid, methacrylic acid, methyl methacrylate, methyl acrylate, and ethyl acrylate; the cross-linking agent is N-hydroxyacrylamide.

2. The water-based self-matting acrylic resin according to claim 1, characterized in that The initiator is ammonium persulfate; the acid-base regulator is ammonia water; and the buffer is sodium bicarbonate.

3. The water-based self-matting acrylic resin according to claim 1, characterized in that The anionic emulsifier is one or both of sodium didodecylphenyl ether disulfonate and sodium laurate; the nonionic emulsifier is one or both of polyoxyethylene ether and ethylene oxide.

4. A method for preparing a water-based self-matting acrylic resin according to claim 1, characterized in that: The fine particle size emulsion and the coarse particle size emulsion are mixed and stirred, and after the reaction is completed, a matte acrylic resin is obtained; The preparation process of the fine particle size emulsion comprises the following steps: S1: Pre-emulsification: Add monomers and 3 / 5 emulsifier A, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion; S2: Seed emulsion: Add 2 / 5 emulsifier A, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 3 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion; S3: Polymerization: Slowly add the remaining 7 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge; The preparation process of the coarse particle size emulsion comprises the following steps: S4: Pre-emulsification: Add monomers and 3 / 5 emulsifier B, mix and heat to dissolve, and stir for 40 minutes to obtain a pre-emulsion; S5: Seed emulsion: Add 2 / 5 emulsifier B, buffer and deionized water, mix and heat to dissolve, add 2 / 5 initiator, increase the temperature, and then add 1 / 10 pre-emulsion and stir for 20 minutes to prepare seed emulsion; S6: Discharging: slowly add the remaining 9 / 10 pre-emulsion and the remaining 3 / 5 initiator to the prepared seed emulsion, keep warm, stir for 3 hours, cool to room temperature, adjust the pH to 7-8, and discharge.

5. The method for preparing the water-based self-matting acrylic resin according to claim 4, wherein: The stirring rate is 500-600 r / min; the temperature in S2 is raised to 75-85° C.; the temperature in S5 is raised to 80-85° C.

6. Use of the water-based self-matting acrylic resin according to claim 1 in the field of poly-ε-caprolactone substrate coating.

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