Waterproof building coating and preparation method thereof

Abstract

The invention discloses a waterproof building coating, which is prepared from the following raw materials in parts by weight: 10 to 20 parts of waterborne inorganic sol-gel resin, 40 to 60 parts of modified waterborne polyurethane, 10 to 20 parts of polyvinyl alcohol solution, 5 to 10 parts of calcium hydroxide, 10 to 20 parts of filler, 10 to 20 parts of pigment, 1 to 5 parts of auxiliaries and 5 to 20 parts of water. The preparation method comprises the following steps: fully and uniformly stirring the water-based inorganic sol-gel resin, the modified water-based polyurethane and the water to obtain a premix; adding calcium hydroxide, a filler, a pigment and an auxiliary agent into the premix, and uniformly stirring to obtain resin color paste; and adding a polyvinyl alcohol solution into the resin color paste, and fully and uniformly stirring to obtain the colloidal waterproof building coating. The polyvinyl alcohol solution and calcium hydroxide are combined for use, so that the durability and antibacterial property of the coating can be remarkably improved, and the synergistic effect can prolong the service life of the coating.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and particularly relates to a waterproof building coating and a preparation method thereof. Background Art

[0002] Waterproof materials mainly include five categories, namely waterproof roll materials, waterproof coatings, sealing materials, rigid waterproof materials and plugging waterproof materials. These waterproof materials have excellent waterproof performance, durability and environmental protection, and are currently widely used in infrastructure fields such as house construction, roads and bridges, and water conservancy and hydropower. Waterproof coating is a general term for materials with specific properties of waterproof membranes. It is mainly based on polymer materials and presents an amorphous liquid state at room temperature. After being brushed, it can be cured on the surface of the structure to form a waterproof membrane with a certain thickness and certain elasticity. Waterproof coatings are widely used in waterproofing and moisture-proofing of structural parts of buildings such as roofs, bathrooms, and basements because of their simple construction and reliable waterproofing effect. There are rich types of waterproof coatings with a wide range of applications. Common ones include polyurethane series, acrylic series, epoxy resin series and cement-based series. Among them, the polyurethane series is a reaction-curing waterproof coating that can be brushed and cured at room temperature. It is easy to operate, and the waterproof layer formed after curing has strong adhesion, large elongation, high strength, and excellent aging resistance. According to the component type, polyurethane waterproof coatings can be divided into single-component and two-component types. The chain extension and curing cross-linking of the one-component polyurethane waterproof coating are achieved through the reaction between the residual -NCO and water in the air during curing, thus forming a waterproof membrane.

[0003] The Chinese patent with application number CN202210511215.4 discloses a polyurethane resin coating, its preparation method and application. The polyurethane resin coating of the invention includes the following components: water-based polyurethane resin, water-based polyacrylate emulsion, surface-modified carbon nanotubes, fillers, curing agents, and water; the surface-modified carbon nanotubes are carbon nanotubes modified by ultrasound using polyethylene glycol and polyacrylate, and the fillers include cement. The invention combines the surface-modified carbon nanotubes with water-based polyurethane resin, water-based polyacrylate emulsion, and fillers to form a coating with good water resistance, corrosion resistance, and mechanical properties at the same time, but the adhesion of the coating is poor, and it cannot conceal the requirements of architectural coatings for adhesion and durability. Therefore, it is urgent to develop a coating with good waterproofness, adhesion, and durability and apply it to the field of construction. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a waterproof building coating and a preparation method thereof. The coating of the present invention has good waterproof performance, strong adhesion ability and high hardness, and can meet the requirements of building coatings.

[0005] The technical solution of the present invention is as follows:

[0006] One of the purposes of the present invention is to provide a waterproof building coating, which is composed of the following raw materials in parts by weight: 10-20 parts of aqueous inorganic sol-gel resin, 40-60 parts of modified aqueous polyurethane, 10-20 parts of polyvinyl alcohol solution, 5-10 parts of calcium hydroxide, 10-20 parts of filler, 10-20 parts of pigment, 1-5 parts of additives, and 5-20 parts of water.

[0007] Furthermore, the aqueous inorganic sol-gel resin is SIVO 140.

[0008] Furthermore, the modified waterborne polyurethane is a silica-modified hydroxyl-type waterborne polyurethane.

[0009] Furthermore, the silica-modified hydroxyl waterborne polyurethane is composed of the following raw materials in parts by weight: 8-10 parts of neopentyl glycol, 3-5 parts of 2,2-dihydroxymethylbutyric acid, 3-5 parts of trimethylolpropane, 30-40 parts of poly(1,4-butylene adipate), 5-6 parts of toluene diisocyanate, 0.1-0.2 parts of dibutyltin dilaurate, 25-30 parts of high-iminomethyl etherified melamine resin, 15-30 parts of water, 3-5 parts of tetraethyl orthosilicate, and 0.1-0.2 parts of γ-glycidyloxypropyltrimethoxysilane.

[0010] Furthermore, the filler is recycled concrete powder.

[0011] Furthermore, the preparation process of the recycled concrete powder is as follows:

[0012] S11: crushing the waste concrete from which impurities have been removed to obtain recycled fine aggregate with a particle size of less than 3 mm;

[0013] S12: Grinding the recycled fine aggregate obtained in step S11, passing through a 200-mesh sieve, and obtaining recycled concrete particles;

[0014] S13: The recycled concrete particles obtained in step S12 are added into a muffle furnace at 800° C. and calcined for 3 hours. After cooling to room temperature, 5% Ca(OH) 2 is added to obtain the recycled concrete powder.

[0015] Furthermore, the pigment is one or more of chromium oxide green, titanium dioxide, molybdenum chrome orange, cadmium red, phthalocyanine blue and iron black.

[0016] Furthermore, the auxiliary agent includes a dispersant and a defoaming agent.

[0017] Furthermore, the dispersant is one or more of sulfated castor oil and sulfate ester salts, and the defoamer is a polyether defoamer.

[0018] A second object of the present invention is to provide a method for preparing a waterproof architectural coating, comprising the following steps:

[0019] S21: fully and uniformly mixing the aqueous inorganic sol-gel resin, the modified aqueous polyurethane and water according to a set ratio to obtain a premix;

[0020] S22: adding calcium hydroxide, fillers, pigments and additives to the premix obtained in step S21 under stirring and stirring evenly to obtain a resin paste;

[0021] S23: Add the polyvinyl alcohol solution to the resin paste obtained in step S22, and stir thoroughly to obtain the colloidal waterproof architectural coating.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention provides a waterproof architectural coating, which significantly improves the comprehensive performance of the coating by using a water-based inorganic sol-gel resin and a modified water-based polyurethane composite. A polyvinyl alcohol solution is used. During the preparation of the coating, the polyvinyl alcohol solution is evenly dispersed in the slurry. During the curing process of the coating, the water evaporates, and the polyvinyl alcohol shrinks and polymerizes to form a network structure, which can be matched with the filler and filled into the gap of the filler, so that the hardened coating is more compact, and the adhesion, waterproofness and surface properties of the coating can be improved. Calcium hydroxide can inhibit the growth of microorganisms and has antibacterial and mildew-proof effects. The combination of calcium hydroxide and polyvinyl alcohol solution can significantly improve the durability of the coating. This synergistic effect can extend the service life of the coating.

[0024] 2. A waterproof building coating provided by the present invention adopts a modified waterborne polyurethane modified with silica-hydroxyl waterborne polyurethane. The silica structure formed by the hydrolysis of tetraethyl orthosilicate is an inorganic network structure. After modification by tetraethyl orthosilicate, an organic-inorganic hybrid material is formed in the polyurethane, which can improve the mechanical strength and corrosion resistance of the polyurethane. The epoxy group in γ-glycidyloxypropyltrimethoxysilane can react with the hydroxyl group in the polyurethane, and the silane group can be combined with the silica surface after hydrolysis, further improving the mechanical strength, heat resistance and impact resistance of the polyurethane. The alkoxy group on the high-iminomethyl etherified melamine resin can react with the carboxyl group and hydroxyl group in the waterborne polyurethane to form a high-density cross-linked structure, thereby improving the mechanical strength, heat resistance and corrosion resistance of the polyurethane. The waterborne polyurethane modified by the three together also has good surface properties, good waterproof performance and high hardness.

[0025] 3. The waterproof building coating provided by the present invention is added with calcium hydroxide, which can improve the adhesion between the coating and the substrate, and the present invention uses recycled concrete powder as a filler, which is more environmentally friendly and can save costs to a certain extent. The recycled concrete powder contains highly active silicon dioxide and aluminum oxide, which can react with calcium hydroxide to generate CSH gel, which can fill the structural gaps of the coating and further improve the mechanical strength of the coating. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with preferred embodiments. The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values; for numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein; the materials, reagents, etc. used in the following embodiments, unless otherwise specified, can be obtained from commercial channels; the experimental methods in the following embodiments, unless otherwise specified, are all conventional methods.

[0027] Example 1

[0028] The present embodiment provides a waterproof building coating, which is composed of the following raw materials in parts by weight: 15 parts of aqueous inorganic sol-gel resin, 50 parts of modified aqueous polyurethane, 15 parts of polyvinyl alcohol solution, 7 parts of calcium hydroxide, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0029] In this embodiment, the aqueous inorganic sol-gel resin is SIVO 140, the modified waterborne polyurethane is a silica-modified hydroxyl-type waterborne polyurethane, the pigment is chromium oxide green, the auxiliary agent includes a dispersant and a defoamer, the dispersant is sulfated castor oil, and the defoamer is a polyether defoamer.

[0030] The silica-modified hydroxyl waterborne polyurethane is composed of the following raw materials in parts by weight: 9 parts of neopentyl glycol, 4 parts of 2,2-dihydroxymethylbutyric acid, 4 parts of trimethylolpropane, 35 parts of poly(1,4-butylene adipate), 5.5 parts of toluene diisocyanate, 0.15 parts of dibutyltin dilaurate, 28 parts of high-iminomethyl etherified melamine resin, 25 parts of water, 4 parts of tetraethyl orthosilicate, and 0.15 parts of γ-glycidyloxypropyltrimethoxysilane.

[0031] In this embodiment, the filler is recycled concrete powder, and the preparation process of the recycled concrete powder is as follows:

[0032] S11: crushing the waste concrete from which impurities have been removed to obtain recycled fine aggregate with a particle size of less than 3 mm;

[0033] S12: Grinding the recycled fine aggregate obtained in step S11, passing through a 200-mesh sieve, and obtaining recycled concrete particles;

[0034] S13: The recycled concrete particles obtained in step S12 are added into a muffle furnace at 800° C. and calcined for 3 hours. After cooling to room temperature, 5% Ca(OH) 2 is added to obtain the recycled concrete powder.

[0035] This embodiment also provides a method for preparing a waterproof architectural coating, comprising the following steps:

[0036] S21: fully and uniformly mixing the aqueous inorganic sol-gel resin, the modified aqueous polyurethane and water according to a set ratio to obtain a premix;

[0037] S22: adding calcium hydroxide, fillers, pigments and additives to the premix obtained in step S21 under stirring and stirring evenly to obtain a resin paste;

[0038] S23: Add the polyvinyl alcohol solution to the resin paste obtained in step S22, and stir thoroughly to obtain the colloidal waterproof architectural coating.

[0039] Example 2

[0040] The present embodiment provides a waterproof building coating, which is composed of the following raw materials in parts by weight: 10 parts of aqueous inorganic sol-gel resin, 40 parts of modified aqueous polyurethane, 10 parts of polyvinyl alcohol solution, 5 parts of calcium hydroxide, 10 parts of filler, 10 parts of pigment, 1 part of additive, and 5 parts of water.

[0041] In this embodiment, the aqueous inorganic sol-gel resin is SIVO 140, the modified waterborne polyurethane is a silica-modified hydroxyl waterborne polyurethane, the pigment is a mixture of titanium dioxide and molybdenum chromium orange, the additives include a dispersant and a defoamer, the dispersant is a sulfate ester salt, and the defoamer is a polyether defoamer.

[0042] The silica-modified hydroxyl waterborne polyurethane is composed of the following raw materials in parts by weight: 8 parts of neopentyl glycol, 3 parts of 2,2-dihydroxymethylbutyric acid, 3 parts of trimethylolpropane, 30 parts of poly(1,4-butylene adipate), 5 parts of toluene diisocyanate, 0.1 parts of dibutyltin dilaurate, 25 parts of high-iminomethyl etherified melamine resin, 15 parts of water, 3 parts of tetraethyl orthosilicate, and 0.1 parts of γ-glycidyloxypropyltrimethoxysilane.

[0043] In this embodiment, the filler is recycled concrete powder, and the preparation process of the recycled concrete powder is as follows:

[0044] S11: crushing the waste concrete from which impurities have been removed to obtain recycled fine aggregate with a particle size of less than 3 mm;

[0045] S12: Grinding the recycled fine aggregate obtained in step S11, passing through a 200-mesh sieve, and obtaining recycled concrete particles;

[0046] S13: The recycled concrete particles obtained in step S12 are added into a muffle furnace at 800° C. and calcined for 3 hours. After cooling to room temperature, 5% Ca(OH) 2 is added to obtain the recycled concrete powder.

[0047] This embodiment also provides a method for preparing a waterproof architectural coating, comprising the following steps:

[0048] S21: fully and uniformly mixing the aqueous inorganic sol-gel resin, the modified aqueous polyurethane and water according to a set ratio to obtain a premix;

[0049] S22: adding calcium hydroxide, fillers, pigments and additives to the premix obtained in step S21 under stirring and stirring evenly to obtain a resin paste;

[0050] S23: Add the polyvinyl alcohol solution to the resin paste obtained in step S22, and stir thoroughly to obtain the colloidal waterproof architectural coating.

[0051] Example 3

[0052] The present embodiment provides a waterproof building coating, which is composed of the following raw materials in parts by weight: 20 parts of aqueous inorganic sol-gel resin, 60 parts of modified aqueous polyurethane, 20 parts of polyvinyl alcohol solution, 10 parts of calcium hydroxide, 20 parts of filler, 20 parts of pigment, 5 parts of additives, and 20 parts of water.

[0053] In this embodiment, the aqueous inorganic sol-gel resin is SIVO 140, the modified waterborne polyurethane is a silica-modified hydroxyl waterborne polyurethane, the pigment is a mixture of cadmium red and phthalocyanine blue, the additives include a dispersant and a defoamer, the dispersant is a mixture of sulfated castor oil and sulfate ester salt, and the defoamer is a polyether defoamer.

[0054] The silica-modified hydroxyl waterborne polyurethane is composed of the following raw materials in parts by weight: 10 parts of neopentyl glycol, 5 parts of 2,2-dihydroxymethylbutyric acid, 5 parts of trimethylolpropane, 40 parts of poly(1,4-butylene adipate), 6 parts of toluene diisocyanate, 0.2 parts of dibutyltin dilaurate, 30 parts of high-iminomethyl etherified melamine resin, 30 parts of water, 5 parts of tetraethyl orthosilicate, and 0.2 parts of γ-glycidyloxypropyltrimethoxysilane.

[0055] In this embodiment, the filler is recycled concrete powder, and the preparation process of the recycled concrete powder is as follows:

[0056] S11: crushing the waste concrete from which impurities have been removed to obtain recycled fine aggregate with a particle size of less than 3 mm;

[0057] S12: Grinding the recycled fine aggregate obtained in step S11, passing through a 200-mesh sieve, and obtaining recycled concrete particles;

[0058] S13: The recycled concrete particles obtained in step S12 are added into a muffle furnace at 800° C. and calcined for 3 hours. After cooling to room temperature, 5% Ca(OH) 2 is added to obtain the recycled concrete powder.

[0059] This embodiment also provides a method for preparing a waterproof architectural coating, comprising the following steps:

[0060] S21: fully and uniformly mixing the aqueous inorganic sol-gel resin, the modified aqueous polyurethane and water according to a set ratio to obtain a premix;

[0061] S22: adding calcium hydroxide, fillers, pigments and additives to the premix obtained in step S21 under stirring and stirring evenly to obtain a resin paste;

[0062] S23: Add the polyvinyl alcohol solution to the resin paste obtained in step S22, and stir thoroughly to obtain the colloidal waterproof architectural coating.

[0063] Example 4

[0064] It is basically the same as Example 1, except that the modified waterborne polyurethane in this example is only modified by tetraethyl orthosilicate and γ-glycidyloxypropyltrimethoxysilane.

[0065] The silica-modified hydroxyl waterborne polyurethane of this embodiment is composed of the following raw materials in parts by weight: 9 parts of neopentyl glycol, 4 parts of 2,2-dihydroxymethylbutyric acid, 4 parts of trimethylolpropane, 35 parts of poly(1,4-butylene adipate), 5.5 parts of toluene diisocyanate, 0.15 parts of dibutyltin dilaurate, 25 parts of water, 4 parts of tetraethyl orthosilicate, and 0.15 parts of γ-glycidyloxypropyltrimethoxysilane.

[0066] Example 5

[0067] The method is basically the same as Example 1, except that the modified waterborne polyurethane in this example is only modified with high iminomethyl etherified melamine resin.

[0068] The silica-modified hydroxyl-type waterborne polyurethane of this embodiment is composed of the following raw materials in parts by weight:

[0069] 9 parts of neopentyl glycol, 4 parts of 2,2-dimethylolbutyric acid, 4 parts of trimethylolpropane, 35 parts of poly(1,4-butylene adipate), 5.5 parts of toluene diisocyanate, 0.15 parts of dibutyltin dilaurate, 28 parts of highly iminomethyletherified melamine resin, and 25 parts of water.

[0070] Example 6

[0071] It is basically the same as Example 1, except that the filler in this example is carbon fiber.

[0072] In this embodiment, the pigment may also be selected from one or more of chromium oxide green, titanium dioxide, molybdenum chrome orange, cadmium red, phthalocyanine blue and iron black.

[0073] Comparative Example 1

[0074] The difference from Example 1 is that the architectural coating of this comparative example does not contain polyvinyl alcohol solution and calcium hydroxide.

[0075] The colloidal waterproof building coating of this comparative example is composed of the following raw materials in parts by weight:

[0076] 15 parts of aqueous inorganic sol-gel resin, 72 parts of modified aqueous polyurethane, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0077] Comparative Example 2

[0078] The difference from Example 1 is that the architectural coating of this comparative example does not contain polyvinyl alcohol solution.

[0079] The colloidal waterproof building coating of this comparative example is composed of the following raw materials in parts by weight:

[0080] 15 parts of aqueous inorganic sol-gel resin, 65 parts of modified aqueous polyurethane, 7 parts of calcium hydroxide, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0081] Comparative Example 3

[0082] The difference from Example 1 is that the architectural coating of this comparative example does not contain calcium hydroxide.

[0083] The colloidal waterproof building coating of this comparative example is composed of the following raw materials in parts by weight:

[0084] 15 parts of aqueous inorganic sol-gel resin, 57 parts of modified aqueous polyurethane, 15 parts of polyvinyl alcohol solution, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0085] Comparative Example 4

[0086] The difference from Example 1 is that the architectural coating of this comparative example does not contain water-based inorganic sol-gel resin.

[0087] The colloidal waterproof building coating of this comparative example is composed of the following raw materials in parts by weight:

[0088] 65 parts of modified waterborne polyurethane, 15 parts of polyvinyl alcohol solution, 7 parts of calcium hydroxide, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0089] Comparative Example 5

[0090] The difference from Example 1 is that the architectural coating of this comparative example does not contain modified waterborne polyurethane.

[0091] The colloidal waterproof building coating of this comparative example is composed of the following raw materials in parts by weight:

[0092] 65 parts of aqueous inorganic sol-gel resin, 15 parts of polyvinyl alcohol solution, 7 parts of calcium hydroxide, 15 parts of filler, 15 parts of pigment, 3 parts of additives, and 15 parts of water.

[0093] Implementation effect evaluation:

[0094] The sample was prepared according to the relevant standard of GB / T 9757-2001, and the size of the sample was 150mm*70mm*5mm. The architectural coatings prepared in Examples 1-6 and Comparative Examples 1-5 and the prepared samples were specifically tested to further illustrate the excellent effect achieved by the present invention:

[0095] Adhesion test: Carry out adhesion test on each sample in accordance with the relevant provisions of GB / T1720-79;

[0096] Water resistance test: immerse the sample in the third-grade water specified in GB / T6682. When the sample shows blistering, powdering or discoloration, stop the test and record the immersion time.

[0097] Contact angle test: The water contact angle of each sample is tested by a contact angle meter;

[0098] Tensile strength, elongation at break, tear strength test: tensile strength, elongation at break, tear strength test of each sample in accordance with the relevant standards of GB / T 16777-2008;

[0099] Hardness test: Conduct hardness test on each sample in accordance with the relevant standards of GB / T 6739-1996;

[0100] Antibacterial performance test: The test strains used were Escherichia coli ATCC8739 and Staphylococcus aureus ATCC6538. According to the relevant standards in AATCC90-1982 "Determination of Antibacterial Activity of Fibers - Plate Culture Method", the antibacterial performance of each sample was evaluated by the inhibition zone method. When the diameter of the inhibition zone was greater than 14 mm, it was judged to have an antibacterial effect; when the diameter of the inhibition zone was less than or equal to 14 mm, it was judged to have no antibacterial effect;

[0101] Antifungal test: The fungi include Aspergillus brasiliensis ATCC9642, Chaetomium globosum ATCC6205, Trichoderma viride ATCC9645, and Aureobasidium pullulans ATCC15233. According to the national standard GB / T1741-1979 (1989), the antifungal performance of each sample was tested by the culture dish method;

[0102] Antibacterial durability test: After 5000 hours of xenon lamp accelerated aging, the changes in the inhibitory and killing effects of each sample on bacteria and mold were tested;

[0103] Aging resistance test: The aging resistance test was carried out on each sample in accordance with the relevant standards of GB / T 23987-2009.

[0104] The performance test results are shown in Table 1 and Table 2:

[0105] Table 1 Test results statistics Table 1

[0106]

[0107]

[0108] Table 2 Test results statistics Table 2

[0109]

[0110]

[0111]

[0112] It can be seen from Table 1 and Table 2 that the waterproof building coating provided by the present invention has good mechanical properties, waterproof properties, durability and antibacterial properties, and the hardened coating has high hardness, strong adhesion and excellent surface properties, and is suitable for use in the construction field.

[0113] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A waterproof architectural coating, characterized in that: The invention is composed of the following raw materials in parts by weight: 10-20 parts of aqueous inorganic sol-gel resin, 40-60 parts of modified aqueous polyurethane, 10-20 parts of polyvinyl alcohol solution, 5-10 parts of calcium hydroxide, 10-20 parts of filler, 10-20 parts of pigment, 1-5 parts of auxiliary agent and 5-20 parts of water.

2. A waterproof architectural coating according to claim 1, characterized in that: The aqueous inorganic sol-gel resin is SIVO 140.

3. A waterproof architectural coating according to claim 1, characterized in that: The modified waterborne polyurethane is a silicon dioxide-modified hydroxyl-type waterborne polyurethane.

4. A waterproof architectural coating according to claim 3, characterized in that: The silica-modified hydroxyl waterborne polyurethane is composed of the following raw materials in parts by weight: 8-10 parts of neopentyl glycol, 3-5 parts of 2,2-dihydroxymethylbutyric acid, 3-5 parts of trimethylolpropane, 30-40 parts of poly(1,4-butylene adipate), 5-6 parts of toluene diisocyanate, 0.1-0.2 parts of dibutyltin dilaurate, 25-30 parts of high-iminomethylether melamine resin, 15-30 parts of water, 3-5 parts of tetraethyl orthosilicate, and 0.1-0.2 parts of γ-glycidyloxypropyltrimethoxysilane.

5. A waterproof architectural coating according to claim 1, characterized in that: The filler is recycled concrete powder.

6. A waterproof architectural coating according to claim 5, characterized in that: The preparation process of the recycled concrete powder is as follows: S11: crushing the waste concrete from which impurities have been removed to obtain recycled fine aggregate with a particle size of less than 3 mm; S12: Grinding the recycled fine aggregate obtained in step S11, passing through a 200-mesh sieve, and obtaining recycled concrete particles; S13: The recycled concrete particles obtained in step S12 are added into a muffle furnace at 800° C. and calcined for 3 hours. After cooling to room temperature, 5% Ca(OH) 2 is added to obtain the recycled concrete powder.

7. A waterproof architectural coating according to claim 1, characterized in that: The pigment is one or more of chromium oxide green, titanium dioxide, molybdenum chromium orange, cadmium red, phthalocyanine blue and iron black.

8. A waterproof architectural coating according to claim 1, characterized in that: The auxiliary agents include dispersants and defoamers.

9. A waterproof architectural coating according to claim 8, characterized in that: The dispersant is one or more of sulfated castor oil and sulfate ester salt, and the defoamer is a polyether defoamer.

10. The method for preparing a waterproof architectural coating according to any one of claims 1 to 9, characterized in that: The following steps are involved: S21: fully and uniformly mixing the aqueous inorganic sol-gel resin, the modified aqueous polyurethane and water according to a set ratio to obtain a premix; S22: adding calcium hydroxide, fillers, pigments and additives to the premix obtained in step S21 under stirring and stirring evenly to obtain a resin paste; S23: Add the polyvinyl alcohol solution to the resin paste obtained in step S22, and stir thoroughly to obtain the colloidal waterproof architectural coating.

Images