High-strength antifouling exterior wall coating and preparation method thereof

Abstract

The invention relates to the field of exterior wall coatings, in particular to a high-strength antifouling exterior wall coating and a preparation method thereof. The high-strength antifouling exterior wall coating is prepared from the following components in parts by weight: 25 to 35 parts of nano rutile type titanium dioxide, 15 to 20 parts of silicon dioxide, 58 to 65 parts of acrylic emulsion, 4 to 6 parts of a coupling agent, 2 to 3 parts of a coalescing agent, 0.05 to 0.2 part of a wetting agent, 0.2 to 1 part of a dispersing agent, 0.3 to 0.5 part of a defoaming agent, 0.3 to 0.5 part of a mildew-proof antibacterial agent, 0.3 to 0.5 part of a thickening agent and 8 to 15 parts of deionized water. The silicon dioxide comprises a first powder material and a second powder material in a mass ratio of 1: (3-5), the fineness of the first powder material is 220-280 meshes, and the fineness of the second powder material is 70-180 meshes. The high-strength antifouling exterior wall coating disclosed by the invention has excellent wear resistance and antifouling property through matching of the nano rutile titanium dioxide, the silicon dioxide and the acrylic emulsion.

Description

Technical Field

[0001] The invention relates to the field of exterior wall coatings, and in particular to a high-strength antifouling exterior wall coating and a preparation method thereof. Background Art

[0002] At present, most of the wall coatings are made of organic polymer emulsions. Although organic polymer emulsions have the advantages of good film-forming properties and good water resistance, they also have disadvantages such as high-temperature re-adhesion, poor resistance, low hardness, and poor UV aging when applied to exterior wall coatings. For example, exterior wall coatings may encounter more collisions with hard objects and require stronger hardness. In addition, exterior walls will also face more pollution from various stains, so their anti-fouling properties become more important. Most of the current exterior wall coatings are doped with inorganic components, such as titanium powder, silicon powder, ceramic powder and other particles. Although the use of these inorganic components can increase the hardness of the coating to a certain extent, it will also cause the anti-fouling properties of the exterior wall coating to decrease. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a high-strength antifouling exterior wall coating and a preparation method thereof, aiming to solve the technical problem of insufficient antifouling performance of exterior wall coatings in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The first aspect of the present invention provides a high-strength antifouling exterior wall coating, wherein the raw materials for its preparation include the following components by weight: 25 to 35 parts of nano rutile titanium dioxide, 15 to 20 parts of silicon dioxide, 58 to 65 parts of acrylic emulsion, 4 to 6 parts of coupling agent, 2 to 3 parts of film-forming aid, 0.05 to 0.2 parts of wetting agent, 0.2 to 1 parts of dispersant, 0.3 to 0.5 parts of defoaming agent, 0.3 to 0.5 parts of mildew and antibacterial agent, 0.3 to 0.5 parts of thickener, and 8 to 15 parts of deionized water; the silicon dioxide includes a first powder and a second powder in a mass ratio of 1: (3 to 5), the fineness of the first powder is 220 to 280 meshes, and the fineness of the second sand material is 70 to 180 meshes.

[0006] The high-strength antifouling exterior wall paint, wherein the acrylic emulsion, in parts by weight, has the following raw materials for preparation: 120-150 parts of styrene, 80-100 parts of isobutyl acrylate, 30-40 parts of methyl methacrylate, 15-20 parts of glycidyl methacrylate, 8-12 parts of N-hydroxymethyl acrylamide, 18-22 parts of adipic acid dihydrazide, 10-15 parts of emulsifier, 1-3 parts of initiator, and 280-320 parts of deionized water.

[0007] The high-strength antifouling exterior wall paint, wherein the coupling agent comprises a silane coupling agent and a titanate coupling agent.

[0008] In the high-strength antifouling exterior wall paint, the mass ratio of the silane coupling agent to the titanate coupling agent is 2:1.

[0009] The high-strength antifouling exterior wall coating, wherein the silane coupling agent is at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane.

[0010] The high-strength antifouling exterior wall paint, wherein the silane coupling agent is N-phenyl-3-aminopropyltrimethoxysilane.

[0011] The high-strength antifouling exterior wall coating, wherein the titanium ester acid coupling agent is at least one of isopropyl dioleyl (dioctyl phosphate) titanate (TMC-101) and isopropyl tris-(dioctyl phosphate) titanate (TMC-102).

[0012] The high-strength antifouling exterior wall paint, wherein the titanium ester acid coupling agent is isopropyl dioleyl acyloxy (dioctyl phosphate acyloxy) titanate (TMC-101).

[0013] The high-strength antifouling exterior wall coating, wherein the film-forming aid is at least one of propylene glycol butyl ether, dipropylene glycol monobutyl ether, and tripropylene glycol n-butyl ether; the dispersant is at least one of polyoxyethylene alkyl phenyl ether, sodium dodecylbenzene sulfonate, fatty acid sulfonalkyl esters, and fatty acid sulfonalkyl amides; and the wetting agent is at least one of glycerol, ethanol, propylene glycol, and dimethyl sulfoxide.

[0014] A second aspect of the present invention provides a method for preparing an exterior wall coating, which is used to prepare the high-strength antifouling exterior wall coating as described above, and is characterized in that it comprises the following steps:

[0015] S001 prepare the raw materials according to the formula, add deionized water, dispersant and wetting agent to the stirrer in turn, stir well at 1000rmp;

[0016] S002. Adjust the speed to 1500rmp, add nano-rutile titanium dioxide and silica;

[0017] S003. Adjust the speed to 1000rmp, add coupling agent, acrylic emulsion and film-forming agent;

[0018] S004. Maintaining the rotation speed at 1000 rpm, adding antiseptic and bactericidal agent, thickener and defoaming agent to obtain the high-strength antifouling exterior wall coating.

[0019] Beneficial effects: The present invention provides a high-strength antifouling exterior wall coating and a preparation method thereof. The high-strength antifouling exterior wall coating is prepared by combining components such as nano-rutile titanium dioxide, silicon dioxide, acrylic emulsion, and coupling agent, and then combining a first powder and a second powder of a specific size and ratio in silicon dioxide, so that the coating has not only high hardness after curing, but also has a dense structure with excellent antifouling performance. DETAILED DESCRIPTION

[0020] The present invention provides a high-strength antifouling exterior wall coating and a preparation method thereof. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The first aspect of the present invention provides a high-strength antifouling exterior wall coating, wherein the raw materials for its preparation include the following components by weight: 25 to 35 parts of nano rutile titanium dioxide, 15 to 20 parts of silicon dioxide, 58 to 65 parts of acrylic emulsion, 4 to 6 parts of coupling agent, 2 to 3 parts of film-forming aid, 0.05 to 0.2 parts of wetting agent, 0.2 to 1 parts of dispersant, 0.3 to 0.5 parts of defoaming agent, 0.3 to 0.5 parts of mildew and antibacterial agent, 0.3 to 0.5 parts of thickener, and 8 to 15 parts of deionized water; the silicon dioxide includes a first powder and a second powder in a mass ratio of 1: (3 to 5), the fineness of the first powder is 220 to 280 meshes, and the fineness of the second sand material is 70 to 180 meshes.

[0022] In the above raw materials, nano rutile titanium dioxide and silicon dioxide play the role of filling and enhancing hardness. Acrylic emulsion can form a complex cross-linked structure, and nano rutile titanium dioxide and silicon dioxide of different sizes can be fully filled into the cross-linked structure, so that the obtained coating structure has better compactness, thereby improving the antifouling performance. Coupling agent is used to improve the connectivity of nano rutile titanium dioxide, silicon dioxide and acrylic emulsion, which can make the connection strength of each component of the coating better and more evenly dispersed. In addition, the present invention also defines the mass ratio and fineness of the first powder and the second powder in silicon dioxide, and within this range, the high-strength antifouling exterior wall coating of the present invention has the highest strength and antifouling performance.

[0023] Preferably, the acrylic emulsion is prepared from the following raw materials by weight: 120-150 parts of styrene, 80-100 parts of isobutyl acrylate, 30-40 parts of methyl methacrylate, 15-20 parts of glycidyl methacrylate, 8-12 parts of N-hydroxymethyl acrylamide, 18-22 parts of adipic acid dihydrazide, 10-15 parts of emulsifier, 1-3 parts of initiator, and 280-320 parts of deionized water. Among the above components, N-hydroxymethyl acrylamide and adipic acid dihydrazide are cross-linking monomers, which can increase the cross-linking density of the acrylic emulsion. Isobutyl acrylate, methyl methacrylate, and glycidyl methacrylate are functional monomers, which can be used to improve the weather resistance and stain resistance of the emulsion.

[0024] Specifically, the preparation method of the acrylic emulsion comprises the following steps:

[0025] A001. Mix 40 to 50 parts of deionized water with 5 to 7 parts of emulsifier to form a kettle bottom emulsion;

[0026] A002. Mix 20 to 30 parts of deionized water with an initiator to prepare an initiator solution;

[0027] A003. The remaining deionized water and the remaining emulsifier were mixed, and styrene, isobutyl acrylate, methyl methacrylate, glycidyl methacrylate, and N-hydroxymethyl acrylamide were added to form a monomer premix;

[0028] A004. The monomer premix and the initiator solution were added dropwise to the emulsion at the bottom of the kettle and mixed, and kept at 85 to 90°C for 200 min to obtain a pre-emulsion;

[0029] A005. Mix the pre-emulsion with adipic acid dihydrazide to obtain the acrylic emulsion.

[0030] Preferably, the coupling agent includes a silane coupling agent and a titanium ester acid coupling agent. The combined use of the silane coupling agent and the titanium ester acid coupling agent can better improve the bonding strength and durability between the organic material and the inorganic material, improve the compatibility and stability of the interface of different materials, enhance the chemical corrosion resistance of the material, and improve the hardness and wear resistance of the material.

[0031] Preferably, the mass ratio of the silane coupling agent to the titanate coupling agent is 2:1.

[0032] Preferably, the silane coupling agent is at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane.

[0033] Preferably, the silane coupling agent is N-phenyl-3-aminopropyltrimethoxysilane. In the system of the present invention, N-phenyl-3-aminopropyltrimethoxysilane has the best use effect.

[0034] Preferably, the titanic acid coupling agent is at least one of isopropyl dioleyl (dioctyl phosphate) titanate (TMC-101) and isopropyl tris-(dioctyl phosphate) titanate (TMC-102).

[0035] Preferably, the titanate coupling agent is isopropyl dioleyl acyloxy (dioctyl phosphate acyloxy) titanate (TMC-101).

[0036] Preferably, the film-forming aid is at least one of propylene glycol butyl ether, dipropylene glycol monobutyl ether and tripropylene glycol n-butyl ether.

[0037] Preferably, the dispersant is at least one of polyoxyethylene alkylphenyl ether, sodium dodecylbenzene sulfonate, fatty acid sulfonalkyl ester, and fatty acid sulfonalkyl amide.

[0038] Preferably, the wetting agent is at least one of glycerol, ethanol, propylene glycol and dimethyl sulfoxide.

[0039] A second aspect of the present invention provides a method for preparing an exterior wall coating, which is used to prepare the high-strength antifouling exterior wall coating as described above, and is characterized in that it comprises the following steps:

[0040] S001 prepare the raw materials according to the formula, add deionized water, dispersant and wetting agent to the stirrer in turn, stir well at 1000rmp;

[0041] S002. Adjust the speed to 1500rmp, add nano-rutile titanium dioxide and silica;

[0042] S003. Adjust the speed to 1000rmp, add coupling agent, acrylic emulsion and film-forming agent;

[0043] S004. Maintaining the rotation speed at 1000 rpm, adding antiseptic and bactericidal agent, thickener and defoaming agent to obtain the high-strength antifouling exterior wall coating.

[0044] The present invention is further described below with reference to specific examples and comparative examples.

[0045] Example 1

[0046] A high-strength antifouling exterior wall paint, wherein the raw materials for its preparation include the following components by weight: 30 parts of nano-rutile titanium dioxide, 18 parts of silicon dioxide, 60 parts of acrylic emulsion, 5 parts of coupling agent, 2 parts of film-forming aid, 0.1 parts of wetting agent, 0.8 parts of dispersant, 0.3 parts of defoaming agent, 0.3 parts of mildew and antibacterial agent, 0.4 parts of thickener, and 12 parts of deionized water;

[0047] The silicon dioxide is composed of a first powder and a second powder in a mass ratio of 1:3, the first powder has a fineness of 220 to 280 meshes, and the second powder has a fineness of 70 to 180 meshes;

[0048] The acrylic emulsion is prepared from the following raw materials by weight: 130 parts of styrene, 85 parts of isobutyl acrylate, 35 parts of methyl methacrylate, 18 parts of glycidyl methacrylate, 10 parts of N-hydroxymethyl acrylamide, 20 parts of adipic acid dihydrazide, 13 parts of emulsifier, 2 parts of initiator, and 300 parts of deionized water;

[0049] The coupling agent is composed of a silane coupling agent and a titanium ester acid coupling agent in a mass ratio of 2:1; the silane coupling agent is N-phenyl-3-aminopropyltrimethoxysilane; the titanium ester acid coupling agent is isopropyl dioleyloxy (dioctylphosphoacyloxy) titanate (TMC-101);

[0050] The film-forming aid is propylene glycol butyl ether; the wetting agent is glycerol; and the dispersant is polyoxyethylene alkyl phenyl ether.

[0051] Example 2

[0052] A high-strength antifouling exterior wall paint, which is different from Example 1 in that its preparation raw materials include the following components: 25 parts of nano rutile titanium dioxide, 20 parts of silicon dioxide, 63 parts of acrylic emulsion, 5 parts of coupling agent, 2 parts of film-forming aid, 0.1 parts of wetting agent, 0.8 parts of dispersant, 0.3 parts of defoaming agent, 0.3 parts of mildew and antibacterial agent, 0.4 parts of thickener, and 12 parts of deionized water;

[0053] The silicon dioxide is composed of a first powder and a second powder in a mass ratio of 1:5.

[0054] Example 3

[0055] A high-strength antifouling exterior wall coating, which differs from Example 1 in that the coupling agent is N-phenyl-3-aminopropyltrimethoxysilane.

[0056] Example 4

[0057] A high-strength antifouling exterior wall coating, which differs from Example 1 in that the silane coupling agent is 3-aminopropyltrimethoxysilane.

[0058] Example 5

[0059] A high-strength antifouling exterior wall paint, which differs from Example 1 in that the titanate acid coupling agent is isopropyl tris-(dioctylphosphoyloxy) titanate (TMC-102).

[0060] Comparative Example 1

[0061] An exterior wall paint, which differs from Example 1 in that the formula of the acrylic emulsion is different;

[0062] In this comparative example, the raw materials for preparing the acrylic emulsion include the following components, measured by weight: 110 parts of styrene, 105 parts of isobutyl acrylate, 35 parts of methyl methacrylate, 18 parts of glycidyl methacrylate, 10 parts of N-hydroxymethyl acrylamide, 20 parts of adipic acid dihydrazide, 13 parts of emulsifier, 2 parts of initiator, and 300 parts of deionized water.

[0063] Comparative Example 2

[0064] An exterior wall paint, which differs from Example 1 in that the formula of the acrylic emulsion is different;

[0065] In this comparative example, the raw materials for preparing the acrylic emulsion include the following components, measured by weight: 130 parts of styrene, 85 parts of isobutyl acrylate, 35 parts of methyl methacrylate, 28 parts of N-hydroxymethyl acrylamide, 20 parts of adipic acid dihydrazide, 13 parts of emulsifier, 2 parts of initiator, and 300 parts of deionized water.

[0066] Comparative Example 3

[0067] An exterior wall paint, which differs from Example 1 in that the silicon dioxide is composed of a first powder and a second powder in a mass ratio of 1:1.

[0068] Comparative Example 4

[0069] An exterior wall paint, which differs from Example 1 in that the silicon dioxide is composed of a first powder and a second powder in a mass ratio of 1:7.

[0070] The various properties of the exterior wall coatings prepared in the above embodiments and comparative examples were measured. The various properties were measured with reference to JG / T24-2018 "Synthetic resin emulsion sand-walled architectural coatings".

[0071] Scrub resistance: Tested according to GB 9266-2009 "Determination of Scrub Resistance of Architectural Paint Coatings".

[0072]

[0073] It can be seen from the above results that the coatings formed by the exterior wall coatings prepared in Examples 1-5 have good stain resistance, water resistance, alkali resistance and scrub resistance.

[0074] Compared with Example 1, the formulas of acrylic emulsions in Comparative Examples 1 and 2 are different. From the test results, the scrub resistance of Comparative Example 1 is significantly reduced, which may be caused by insufficient styrene dosage. The stain resistance, water resistance and alkali resistance of Comparative Example 2 are significantly reduced. This is because the acrylic emulsion in Comparative Example 2 does not use glycidyl methacrylate, resulting in a decrease in the stain resistance and water resistance of the acrylic emulsion.

[0075] Compared with Example 1, the amount of the first powder used in Comparative Example 3 is more, and the amount of the second powder used is less. Compared with Example 1, the amount of the first powder used in Comparative Example 4 is less, and the amount of the second powder used is more. From the results, the effects of Comparative Examples 3 and 4 are not as good as those of Example 1, which shows that when the ratio of the first powder to the second powder is not appropriate, the coating cannot form the most dense structure, so that stains or water can more easily enter the interior of the structure, which not only makes it difficult to clean the stains and has poor stain resistance, but also significantly reduces the water resistance and alkali resistance of the coating.

[0076] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A high-strength antifouling exterior wall coating, characterized in that: The raw materials for its preparation include the following components by weight: 25 to 35 parts of nano rutile titanium dioxide, 15 to 20 parts of silicon dioxide, 58 to 65 parts of acrylic emulsion, 4 to 6 parts of coupling agent, 2 to 3 parts of film-forming aid, 0.05 to 0.2 parts of wetting agent, 0.2 to 1 parts of dispersant, 0.3 to 0.5 parts of defoaming agent, 0.3 to 0.5 parts of mildew and antibacterial agent, 0.3 to 0.5 parts of thickener, and 8 to 15 parts of deionized water; the silicon dioxide includes a first powder and a second powder in a mass ratio of 1: (3 to 5), the fineness of the first powder is 220 to 280 meshes, and the fineness of the second sand material is 70 to 180 meshes.

2. The high-strength antifouling exterior wall paint according to claim 1, characterized in that: The acrylic emulsion comprises the following components in parts by weight: 120-150 parts of styrene, 80-100 parts of isobutyl acrylate, 30-40 parts of methyl methacrylate, 15-20 parts of glycidyl methacrylate, 8-12 parts of N-hydroxymethyl acrylamide, 18-22 parts of adipic acid dihydrazide, 10-15 parts of emulsifier, 1-3 parts of initiator, and 280-320 parts of deionized water.

3. The high-strength antifouling exterior wall paint according to claim 1, characterized in that: The coupling agent includes a silane coupling agent and a titanate coupling agent.

4. The high-strength antifouling exterior wall paint according to claim 3, characterized in that: The mass ratio of the silane coupling agent to the titanium ester acid coupling agent is 2:

1.

5. The high-strength antifouling exterior wall paint according to claim 4, characterized in that: The silane coupling agent is at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane.

6. The high-strength antifouling exterior wall paint according to claim 4, characterized in that: The silane coupling agent is N-phenyl-3-aminopropyltrimethoxysilane.

7. The high-strength antifouling exterior wall paint according to claim 4, characterized in that: The titanium ester acid coupling agent is at least one of isopropyl dioleyl (dioctyl phosphate) titanate (TMC-101) and isopropyl tris-(dioctyl phosphate) titanate (TMC-102).

8. The high-strength antifouling exterior wall paint according to claim 4, characterized in that: The titanium ester acid coupling agent is isopropyl dioleyl acyloxy (dioctyl phosphate acyloxy) titanate (TMC-101).

9. The high-strength antifouling exterior wall paint according to claim 1, characterized in that: The film-forming aid is at least one of propylene glycol butyl ether, dipropylene glycol monobutyl ether, and tripropylene glycol n-butyl ether; the dispersant is at least one of polyoxyethylene alkyl phenyl ether, sodium dodecylbenzene sulfonate, fatty acid sulfonalkyl ester, and fatty acid sulfonalkyl amide; and the wetting agent is at least one of glycerol, ethanol, propylene glycol, and dimethyl sulfoxide.

10. A method for preparing an exterior wall coating, for preparing the high-strength antifouling exterior wall coating according to any one of claims 1 to 9, characterized in that: The steps include: S001 prepare the raw materials according to the formula, add deionized water, dispersant and wetting agent to the stirrer in turn, stir well at 1000rmp; S002. Adjust the speed to 1500rmp, add nano-rutile titanium dioxide and silica; S003. Adjust the speed to 1000rmp, add coupling agent, acrylic emulsion and film-forming agent; S004. Maintaining the rotation speed at 1000 rpm, adding antiseptic and bactericidal agent, thickener and defoaming agent to obtain the high-strength antifouling exterior wall coating.

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