Exterior wall coating with strong binding power and preparation method thereof

Abstract

The invention discloses an exterior wall coating with strong binding power and a preparation method thereof, and relates to the technical field of building materials. When the exterior wall coating with strong binding power is prepared, 3-aminopropyl pentamethyldisiloxane and 2, 4-divinyl-2, 4, 6, 6, 8, 8-hexamethylcyclotetrasiloxane are subjected to a reaction, and then the reaction product and glutaraldehyde are subjected to a reaction to prepare hydroformylated polysiloxane; carrying out reaction on hydroformylated polysiloxane and vegetable protein peptide to prepare modified vegetable protein peptide; the preparation method comprises the following steps: reacting hydroxylamine hydrochloride with methyl methacrylate, then reacting with acetic anhydride to prepare a photo-thermal response monomer, polymerizing methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate and the photo-thermal response monomer, and emulsifying through modified plant protein peptide to prepare a polymer emulsion; the cement, the allyltriethoxysilane, the 3-aminopropyltriethoxysilane, the potassium persulfate, the pure water and the acrylate emulsion are mixed to prepare the exterior wall coating with strong binding power. The exterior wall coating with strong binding power prepared by the invention has good binding performance and corrosion resistance.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to an exterior wall coating with strong bonding force and a preparation method thereof. Background Art

[0002] Architectural coatings are a general term for a class of liquid or solid materials that can be applied to the surface of a building to form a solid coating with protective, decorative or special properties. Generally, coatings used for interior walls, exterior walls, ceilings, floors, and bathrooms of buildings are called architectural coatings. As a relatively important and largest-volume coating variety, architectural coatings are one of the widely used architectural decoration materials at home and abroad. Architectural coatings have unique advantages: First, from the perspective of decorative function, architectural coatings can create colorful and rich decorative effects. They can be solemn and elegant, or bright and lively, which meets the personalized pursuit of people today; second, architectural coatings are easy to update. When a building decorated with architectural coatings needs to redecorate its appearance, it can be easily reapplied, and the cost is low, which can meet the needs of frequent updates of building exterior decoration; third, from the perspective of construction, architectural coatings themselves are light in weight and can be easily and quickly applied to buildings, with high construction efficiency. After long-term use, there are no safety hazards such as exterior wall tiles and mosaics that are easy to fall off.

[0003] In addition to the decorative function, the surface coating of concrete structure buildings should also have a protective function. Before the exterior wall of the building is decorated, most of them are plastered with cement mortar as the base. Due to the inherent characteristics of cement-based materials, cracks often occur when affected by environmental factors such as temperature changes, dry-wet alternation, freeze-thaw cycles, and base settlement. If its surface is decorated with ordinary exterior wall paint, as the cracks in the base are generated and expanded, the coating will also crack. When the wall surface is eroded by moisture, the moisture will penetrate into the cracks and further penetrate into the interior. In addition to further expanding the cracks due to various external forces, it may also cause corrosion of the steel bars inside the concrete, and even affect the use function of the building; when eroded by acidic gases such as carbon dioxide in the atmosphere and other corrosive gases, these corrosive gases will corrode the coating, internal cement mortar and concrete, causing carbonization of the concrete, and may also affect the steel bars inside the structure. With the extension of time and the accumulation of the above-mentioned destructive factors, the cracks in the base will further increase and deepen, which will have an adverse effect on the building and even cause serious harm. Therefore, it is necessary to modify the exterior wall coatings of buildings so that they have good waterproof and corrosion resistance, thereby improving the protective effect on buildings. Summary of the invention

[0004] The purpose of the present invention is to provide an exterior wall coating with strong bonding force and a preparation method thereof, so as to solve the problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The invention discloses an exterior wall paint with strong bonding force, which mainly comprises, by weight, 20-30 parts of cement, 14-18 parts of polymer emulsion, 5-7 parts of pure water, 2-3 parts of allyl triethoxy silane, 2-3 parts of 3-aminopropyl triethoxy silane and 0.1-0.2 parts of potassium persulfate.

[0007] As an optimization, the polymer emulsion is prepared by free radical-initiated polymerization of methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, and photothermal responsive monomers, and emulsified by modified plant protein peptides.

[0008] As an optimization, the photothermal responsive monomer is prepared by reacting hydroxylamine hydrochloride with methyl methacrylate and then with acetic anhydride.

[0009] As an optimization, the modified plant protein peptide is prepared by reacting 3-aminopropyl pentamethyldisiloxane with 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane, and then reacting with glutaraldehyde to obtain a aldehyded polysiloxane; the aldehyded polysiloxane is reacted with the plant protein peptide to obtain the peptide.

[0010] A method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0011] (1) Methacryloyl hydroxamic acid and dichloromethane are mixed uniformly in a mass ratio of 1:14-16, and under the stirring conditions of 100-200 r / min at 10-20° C., an 8-10% sodium hydroxide aqueous solution with a mass fraction of 5-6 times the mass of the methacryloyl hydroxamic acid is added at a uniform rate within 10-15 minutes. After the addition is completed, stirring is continued for 8-12 minutes, and then acetic anhydride with a mass of 1-1.1 times the mass of the methacryloyl hydroxamic acid is added, and stirring is continued for 20-24 hours. The mixture is washed with a mixture of pure water and dichloromethane for 3-5 times, and after standing and stratification, the organic phase is taken and dried at 20-30° C. and 50-100 Pa for 3-4 hours to obtain a photothermal response monomer;

[0012] (2) The amino-terminated polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly at a mass ratio of 1:1:0.1-0.2:6-8:6-8, ultrasonically reacted at 75-85°C and 25-35kHz for 3-5 hours, and dried at 40-50°C and 10-50Pa for 8-10 hours to obtain the aldehyded polysiloxane; the plant protein peptide, aldehyded polysiloxane, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly at a mass ratio of 1:0.6-0.7:0.08-0.1:4-6:4-6, ultrasonically reacted at 75-85°C and 25-35kHz for 3-5 hours, and dried at 40-50°C and 10-50Pa for 8-10 hours to obtain the modified plant protein peptide;

[0013] (3) The modified plant protein peptide and pure water are mixed uniformly in a mass ratio of 1:20-30 as a reaction base liquid, and a monomer mixed emulsion with a mass of 1.4-1.6 times the mass of the reaction base liquid and a thermal initiation solution with a mass of 0.7-0.8 times the mass of the reaction base liquid are added dropwise at 60°C and 300-500 r / min for 80-100 minutes. After the addition is completed, the temperature is kept unchanged and the reaction is continued for 10-12 hours. The polymer emulsion is concentrated at 30-40°C and 50-100 Pa to a water content of 40-42%, thereby obtaining a polymer emulsion;

[0014] (4) Weigh 20 to 30 parts of cement, 14 to 18 parts of polymer emulsion, 5 to 7 parts of pure water, 2 to 3 parts of allyl triethoxysilane, 2 to 3 parts of 3-aminopropyl triethoxysilane, and 0.1 to 0.2 parts of potassium persulfate according to their mass fractions; mix the cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 20 to 30° C. and 600 to 800 r / min for 3 to 4 minutes, then add the acrylic emulsion and continue stirring for 20 to 30 minutes to obtain an exterior wall coating with strong adhesion.

[0015] As an optimization, the preparation method of the methacryloyl hydroxamic acid in step (1) is as follows: methyl methacrylate and methanol are mixed uniformly in a mass ratio of 1:4-6 to prepare a methyl methacrylate solution; in a nitrogen atmosphere, hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed uniformly in a mass ratio of 1:1.1-1.3:6-8, and under the stirring conditions of 0-5°C and 100-200r / min, methyl methacrylate solution with a mass of 5-7 times of hydroxylamine hydrochloride is added at a uniform speed within 20-25min, and after the addition is completed, the temperature is raised to 20-25°C and stirring is continued for 20-24h to prepare the product.

[0016] As an optimization, the preparation method of the amino-terminated polysiloxane in step (2) is as follows: 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane are uniformly mixed in a mass ratio of 1:3 to 1:4, and then 0.1 to 0.2 times the mass of 3-aminopropyl pentamethyldisiloxane is added with a mass fraction of 98% concentrated sulfuric acid, and the mixture is stirred at 80 to 90° C. and 800 to 1000 r / min for 2 to 3 hours. After cooling to room temperature, calcium hydroxide is added to adjust the pH value to 6 to 7, and the mixture is washed 3 to 5 times with a mixture of pure water and n-heptane in a volume ratio of 1:1, and the oil phase is taken out after standing and layering, and dried at 40 to 50° C. and 10 to 50 Pa for 8 to 10 hours to prepare the polysiloxane.

[0017] As an optimization, the plant protein peptide in step (2) is a mixture of one or more of soybean plant protein peptide, corn plant protein peptide, peanut plant protein peptide, and wheat plant protein peptide, and has a molecular weight of 3000 to 5000 Da.

[0018] As an optimization, the monomer mixed emulsion in step (3) is prepared by uniformly mixing methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide, and pure water in a mass ratio of 1:1:1:1:0.2-0.3:8-10; the thermal initiation solution is prepared by uniformly mixing azobisisobutyronitrile and pure water in a mass ratio of 1:18-20; and the water content is the mass fraction of water.

[0019] As an optimization, the cement in step (4) is one or a mixture of silicate cement, ordinary silicate cement, slag silicate cement, pozzolanic silicate cement, fly ash silicate cement, and composite silicate cement.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] When preparing the exterior wall paint with strong bonding force, the present invention mixes cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, pure water and acrylic ester emulsion to prepare the exterior wall paint with strong bonding force.

[0022] First, 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane are reacted, and then reacted with glutaraldehyde to obtain a hydroformylated polysiloxane; the hydroformylated polysiloxane and plant protein peptide are reacted to obtain a modified plant protein peptide, and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane is used to make the prepared modified plant protein peptide contain a large number of carbon-carbon double bonds, which can be polymerized by free radical unsaturated bonds under the initiation of potassium persulfate to form a cross-linked network, thereby improving the bonding performance and corrosion resistance; the hydroformylated polysiloxane is used to modify the plant protein peptide, so that one end of the plant protein peptide is hydrophilic and the other end is hydrophobic, and the plant protein peptide has good emulsification and wetting effects, so that the organic components and inorganic components in the whole are mixed and dispersed more evenly, thereby improving the bonding performance and corrosion resistance.

[0023] Secondly, hydroxylamine hydrochloride is reacted with methyl methacrylate and then reacted with acetic anhydride to obtain a photothermal response monomer, methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate and the photothermal response monomer are polymerized, and the polymer emulsion is obtained by emulsification through modified plant protein peptides. In the preparation process of the polymer emulsion, the photothermal response monomer is used to participate in the copolymerization, so that the copolymer can undergo a Lossen rearrangement reaction under the action of cement hydration heat or sunlight exposure to generate an isocyanate group, which can react with the hydroxyl group introduced by the copolymerization of hydroxyethyl methacrylate, or with the amino group and carboxyl group contained in other components, so as to further improve the degree of cross-linking and make the structure more stable and dense, thereby improving the bonding performance and corrosion resistance. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of the exterior wall coatings with strong bonding strength prepared in the following examples are as follows:

[0026] Adhesion performance: The exterior wall coatings with strong adhesion obtained in each embodiment and the comparative material were coated on a test panel and cured into a 0.5 mm thick paint film. According to GBT9755-2014, the adhesion test method was adopted. Three horizontal cuts were made on the test panel coated with the paint film with a single-edged tool, and then three cuts were made in the direction perpendicular to the horizontal direction. The distance between each cut was 3 mm, so that the number of grids was 4. Then, a tape tear test was performed and the adhesion level was recorded.

[0027] Corrosion resistance: The exterior wall coatings with strong adhesion obtained in each embodiment and the comparative material are made into 5cm*5cm*5cm samples and weighed, cured for 28 days, immersed in a hydrochloric acid solution with a pH of 1, allowed to stand at 30°C for 72h, washed and dried, and weighed again. The mass difference before and after was calculated and recorded as the corrosion amount.

[0028] Example 1

[0029] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0030] (1) Methyl methacrylate and methanol are mixed in a mass ratio of 1:4 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed in a mass ratio of 1:1.1:6 in a nitrogen atmosphere, and methyl methacrylate solution of 5 times the mass of hydroxylamine hydrochloride is added at a uniform rate within 20 minutes at 0°C and 100 r / min stirring conditions. After the addition is completed, the temperature is raised to 20°C and stirring is continued for 24 hours to prepare methacryloyl hydroxamic acid; methacryloyl hydroxamic acid and dichloro Methane was mixed evenly at a mass ratio of 1:14, and an 8% sodium hydroxide aqueous solution with a mass fraction of 5 times the mass of methacryloyl hydroxamic acid was added at a uniform speed within 15 minutes under the stirring conditions of 100r / min at 10°C. After the addition was completed, stirring was continued for 12 minutes, and then acetic anhydride with a mass of 1 times the mass of methacryloyl hydroxamic acid was added, and stirring was continued for 24 hours. The mixture was washed with a mixture of pure water and dichloromethane for 3 times, and the organic phase was taken after standing and stratification, and dried at 20°C and 50Pa for 4 hours to obtain a photothermal response monomer;

[0031] (2) 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane were mixed uniformly in a mass ratio of 1:3, and then 0.1 times the mass of 3-aminopropyl pentamethyldisiloxane was added with 98% concentrated sulfuric acid, and the mixture was stirred at 80° C. and 800 r / min for 3 h. After cooling to room temperature, calcium hydroxide was added to adjust the pH value to 6, and the mixture was washed three times with pure water and n-heptane in a volume ratio of 1:1, and the oil phase was taken out after standing and stratification, and dried at 40° C. and 10 Pa for 10 h to obtain amino-terminated polysiloxane. ; The amino-terminated polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol and n-heptane were mixed uniformly in the ratio of 1:1:0.1:6:6 by mass, and ultrasonically reacted at 75°C and 25kHz for 5 hours, and dried at 40°C and 10Pa for 10 hours to obtain the hydroformylated polysiloxane; The soybean plant protein peptide with a molecular weight of 3000Da, hydroformylated polysiloxane, acetic acid, anhydrous ethanol and n-heptane were mixed uniformly in the ratio of 1:0.6:0.08:4:4 by mass, and ultrasonically reacted at 75°C and 25kHz for 5 hours, and dried at 40°C and 10Pa for 10 hours to obtain the modified plant protein peptide;

[0032] (3) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide, and pure water are mixed in a mass ratio of 1:1:1:1:0.2:8 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:18 to prepare a thermal initiation solution; modified plant protein peptide and pure water are mixed in a mass ratio of 1:20 to prepare a reaction base liquid, and under stirring conditions of 60°C and 300 r / min, a monomer mixed emulsion with a mass of 1.4 times the mass of the reaction base liquid and a thermal initiation solution with a mass of 0.7 times the mass of the reaction base liquid are simultaneously added dropwise within 100 minutes. After the addition is completed, the temperature is maintained unchanged and the reaction is continued for 12 hours, and the water content is concentrated to 40% at 30°C and 50 Pa to obtain a polymer emulsion;

[0033] (4) Weigh 20 parts of PO42.5 ordinary Portland cement, 14 parts of polymer emulsion, 5 parts of pure water, 2 parts of allyl triethoxysilane, 2 parts of 3-aminopropyl triethoxysilane, and 0.1 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 20° C. and 600 r / min for 4 minutes, then add acrylic emulsion and continue stirring for 30 minutes to prepare an exterior wall coating with strong adhesion.

[0034] Example 2

[0035] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0036] (1) Methyl methacrylate and methanol are mixed in a mass ratio of 1:5 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed in a mass ratio of 1:1.2:7 in a nitrogen atmosphere, and methyl methacrylate solution of 6 times the mass of hydroxylamine hydrochloride is added at a constant speed within 22 minutes at 2.5°C and 150 r / min stirring conditions. After the addition is completed, the temperature is raised to 22.5°C and stirring is continued for 22 hours to prepare methacryloyl hydroxamic acid; methacryloyl hydroxamic acid and dichloromethane are mixed. The alkane was mixed uniformly at a mass ratio of 1:15, and a 9% sodium hydroxide aqueous solution with a mass fraction of 5.5 times the mass of methacryloyl hydroxamic acid was added at a uniform rate within 12 minutes under the stirring condition of 15°C and 150r / min. After the addition was completed, stirring was continued for 10 minutes, and then acetic anhydride with a mass fraction of 1.05 times the mass of methacryloyl hydroxamic acid was added, and stirring was continued for 22 hours. The mixture was washed with pure water and dichloromethane for 4 times, and the organic phase was taken after standing and stratification, and dried at 25°C and 75Pa for 3.5 hours to obtain a photothermal response monomer;

[0037] (2) 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane were mixed uniformly at a mass ratio of 1:3.5, and then 0.15 times the mass of 3-aminopropyl pentamethyldisiloxane was added with 98% concentrated sulfuric acid, and the mixture was stirred at 85°C and 900 r / min for 2.5 hours. After cooling to room temperature, calcium hydroxide was added to adjust the pH to 6.5, and the mixture was washed four times with pure water and n-heptane at a volume ratio of 1:1, and the oil phase was taken out after standing and layering, and dried at 45°C and 30 Pa for 9 hours to obtain amino-terminated poly(vinyl alcohol) Siloxane; amino-terminated polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol, and n-heptane were mixed uniformly at a mass ratio of 1:1:0.15:7:7, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain aldehyded polysiloxane; soybean plant protein peptide with a molecular weight of 4000Da, aldehyded polysiloxane, acetic acid, anhydrous ethanol, and n-heptane were mixed uniformly at a mass ratio of 1:0.65:0.09:5:5, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain modified plant protein peptide;

[0038] (3) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide, and pure water are mixed in a mass ratio of 1:1:1:1:0.25:9 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:19 to prepare a thermal initiation solution; modified plant protein peptide and pure water are mixed in a mass ratio of 1:25 as a reaction base liquid, and under stirring conditions of 60°C and 400 r / min, 1.5 times the mass of the monomer mixed emulsion and 0.75 times the mass of the reaction base liquid The thermal initiation solution is simultaneously added dropwise within 90 minutes. After the addition is completed, the temperature is maintained unchanged and the reaction is continued for 11 hours. At 35°C and 75Pa, it is concentrated to a water content of 41% to obtain a polymer emulsion;

[0039] (4) Weigh 25 parts of PO42.5 ordinary Portland cement, 16 parts of polymer emulsion, 6 parts of pure water, 2.5 parts of allyl triethoxysilane, 2.5 parts of 3-aminopropyl triethoxysilane, and 0.15 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 25° C. and 700 r / min for 3.5 min, then add acrylic emulsion and continue stirring for 25 min to prepare an exterior wall coating with strong adhesion.

[0040] Example 3

[0041] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0042] (1) Methyl methacrylate and methanol are mixed in a mass ratio of 1:6 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed in a mass ratio of 1:1.3:8 in a nitrogen atmosphere, and methyl methacrylate solution of 7 times the mass of hydroxylamine hydrochloride is added at a constant speed within 25 minutes at 5°C and 100-200 r / min stirring conditions. After the addition is completed, the temperature is raised to 25°C and stirring is continued for 20 hours to prepare methacryloyl hydroxamic acid; methacryloyl hydroxamic acid and dihydroxamic acid are mixed. The methyl chloride was mixed uniformly at a mass ratio of 1:16, and a 10% sodium hydroxide aqueous solution with a mass fraction of 6 times the mass of methacryloyl hydroxamic acid was added at a uniform speed within 15 minutes under the stirring conditions of 20°C and 200r / min. After the addition was completed, stirring was continued for 8 minutes, and then acetic anhydride with a mass of 1.1 times the mass of methacryloyl hydroxamic acid was added, and stirring was continued for 24 hours. The mixture was washed with a mixture of pure water and dichloromethane for 5 times, and the organic phase was taken after standing and stratification, and dried at 30°C and 100Pa for 3 hours to obtain a photothermal response monomer;

[0043] (2) 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane were mixed uniformly in a mass ratio of 1:4, and then 0.2 times the mass of 3-aminopropyl pentamethyldisiloxane was added with 98% concentrated sulfuric acid, and the mixture was stirred at 90° C. and 1000 r / min for 2 h. After cooling to room temperature, calcium hydroxide was added to adjust the pH value to 7, and the mixture was washed 5 times with pure water and n-heptane in a volume ratio of 1:1, and the oil phase was taken out after standing and layering, and dried at 50° C. and 50 Pa for 8 h to obtain amino-terminated polysilicone The terminal amino polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol and n-heptane were mixed in a mass ratio of 1:1:0.2:8:8, ultrasonically reacted at 85°C and 35kHz for 3 hours, and dried at 50°C and 50Pa for 8 hours to obtain the aldehyded polysiloxane; the soybean plant protein peptide with a molecular weight of 5000Da, the aldehyded polysiloxane, acetic acid, anhydrous ethanol and n-heptane were mixed in a mass ratio of 1:0.7:0.1:6:6, ultrasonically reacted at 85°C and 35kHz for 3 hours, and dried at 50°C and 50Pa for 8 hours to obtain the modified plant protein peptide;

[0044] (3) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide, and pure water are mixed in a mass ratio of 1:1:1:1:0.3:10 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:20 to prepare a thermal initiation solution; modified plant protein peptide and pure water are mixed in a mass ratio of 1:30 as a reaction base liquid, and under stirring conditions of 60°C and 500r / min, 1.6 times the mass of the monomer mixed emulsion and 0.8 times the mass of the reaction base liquid are simultaneously added dropwise within 100 minutes. After the addition is completed, the temperature is maintained unchanged and the reaction is continued for 10 hours. At 40°C and 100Pa, the water content is concentrated to 42%, thereby obtaining a polymer emulsion;

[0045] (4) Weigh 30 parts of PO42.5 ordinary Portland cement, 18 parts of polymer emulsion, 7 parts of pure water, 3 parts of allyl triethoxysilane, 3 parts of 3-aminopropyl triethoxysilane, and 0.2 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 30°C and 800 r / min for 3 minutes, then add acrylic emulsion and continue stirring for 20 minutes to prepare an exterior wall coating with strong adhesion.

[0046] Comparative Example 1

[0047] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0048] (1) 3-aminopropyl pentamethyl disiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane were mixed uniformly in a mass ratio of 1:3.5, and then 0.15 times the mass of 3-aminopropyl pentamethyl disiloxane was added with 98% concentrated sulfuric acid, and the mixture was stirred at 85°C and 900 r / min for 2.5 hours. After cooling to room temperature, calcium hydroxide was added to adjust the pH to 6.5, and the mixture was washed four times with pure water and n-heptane in a volume ratio of 1:1, and the oil phase was taken out after standing and layering, and dried at 45°C and 30 Pa for 9 hours to obtain amino-terminated polysiloxane. Siloxane; amino-terminated polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol, and n-heptane were mixed uniformly at a mass ratio of 1:1:0.15:7:7, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain aldehyded polysiloxane; soybean plant protein peptide with a molecular weight of 4000Da, aldehyded polysiloxane, acetic acid, anhydrous ethanol, and n-heptane were mixed uniformly at a mass ratio of 1:0.65:0.09:5:5, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain modified plant protein peptide;

[0049] (2) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, modified plant protein peptide, and pure water are mixed in a mass ratio of 1:1:1:0.25:9 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:19 to prepare a thermal initiation solution; modified plant protein peptide and pure water are mixed in a mass ratio of 1:25 to prepare a reaction base liquid, and under stirring conditions of 60°C and 400 r / min, a monomer mixed emulsion with a mass of 1.5 times that of the reaction base liquid and a thermal initiation solution with a mass of 0.75 times that of the reaction base liquid are simultaneously added dropwise within 90 minutes. After the addition is completed, the temperature is kept unchanged and the reaction is continued for 11 hours. The mixture is concentrated at 35°C and 75 Pa to a water content of 41%, thereby obtaining a polymer emulsion;

[0050] (3) Weigh 25 parts of PO42.5 ordinary Portland cement, 16 parts of polymer emulsion, 6 parts of pure water, 2.5 parts of allyl triethoxysilane, 2.5 parts of 3-aminopropyl triethoxysilane, and 0.15 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 25° C. and 700 r / min for 3.5 min, then add acrylic emulsion and continue stirring for 25 min to prepare an exterior wall coating with strong adhesion.

[0051] Comparative Example 2

[0052] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0053] (1) Methyl methacrylate and methanol are mixed in a mass ratio of 1:5 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed in a mass ratio of 1:1.2:7 in a nitrogen atmosphere, and methyl methacrylate solution of 6 times the mass of hydroxylamine hydrochloride is added at a constant speed within 22 minutes at 2.5°C and 150 r / min stirring conditions. After the addition is completed, the temperature is raised to 22.5°C and stirring is continued for 22 hours to prepare methacryloyl hydroxamic acid; methacryloyl hydroxamic acid and dichloromethane are mixed. The alkane was mixed uniformly at a mass ratio of 1:15, and a 9% sodium hydroxide aqueous solution with a mass fraction of 5.5 times the mass of methacryloyl hydroxamic acid was added at a uniform rate within 12 minutes under the stirring condition of 15°C and 150r / min. After the addition was completed, stirring was continued for 10 minutes, and then acetic anhydride with a mass fraction of 1.05 times the mass of methacryloyl hydroxamic acid was added, and stirring was continued for 22 hours. The mixture was washed with pure water and dichloromethane for 4 times, and the organic phase was taken after standing and stratification, and dried at 25°C and 75Pa for 3.5 hours to obtain a photothermal response monomer;

[0054] (2) 3-aminopropyl pentamethyldisiloxane and octamethylcyclotetrasiloxane were mixed uniformly in a mass ratio of 1:3.5, and then 0.15 times the mass of 3-aminopropyl pentamethyldisiloxane was added with 98% concentrated sulfuric acid, and the mixture was stirred at 85°C and 900 r / min for 2.5 hours. After cooling to room temperature, calcium hydroxide was added to adjust the pH value to 6.5, and the mixture was washed four times with pure water and n-heptane in a volume ratio of 1:1, and the oil phase was taken out after standing and stratified, and dried at 45°C and 30 Pa for 9 hours to obtain amino-terminated polysiloxane; amino-terminated polysiloxane Oxyethane, glutaraldehyde, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly in a mass ratio of 1:1:0.15:7:7, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain aldehyded polysiloxane; soybean plant protein peptide with a molecular weight of 4000Da, aldehyded polysiloxane, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly in a mass ratio of 1:0.65:0.09:5:5, ultrasonically reacted at 80°C and 30kHz for 4 hours, and dried at 45°C and 30Pa for 9 hours to obtain modified plant protein peptide;

[0055] (3) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide, and pure water are mixed in a mass ratio of 1:1:1:1:0.25:9 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:19 to prepare a thermal initiation solution; modified plant protein peptide and pure water are mixed in a mass ratio of 1:25 as a reaction base liquid, and under stirring conditions of 60°C and 400 r / min, 1.5 times the mass of the monomer mixed emulsion and 0.75 times the mass of the reaction base liquid The thermal initiation solution is simultaneously added dropwise within 90 minutes. After the addition is completed, the temperature is maintained unchanged and the reaction is continued for 11 hours. At 35°C and 75Pa, it is concentrated to a water content of 41% to obtain a polymer emulsion;

[0056] (4) Weigh 25 parts of PO42.5 ordinary Portland cement, 16 parts of polymer emulsion, 6 parts of pure water, 2.5 parts of allyl triethoxysilane, 2.5 parts of 3-aminopropyl triethoxysilane, and 0.15 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 25° C. and 700 r / min for 3.5 min, then add acrylic emulsion and continue stirring for 25 min to prepare an exterior wall coating with strong adhesion.

[0057] Comparative Example 3

[0058] A method for preparing an exterior wall coating with strong bonding strength, the method for preparing an exterior wall coating with strong bonding strength mainly comprises the following preparation steps:

[0059] (1) Methyl methacrylate and methanol are mixed in a mass ratio of 1:5 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed in a mass ratio of 1:1.2:7 in a nitrogen atmosphere, and methyl methacrylate solution of 6 times the mass of hydroxylamine hydrochloride is added at a constant speed within 22 minutes at 2.5°C and 150 r / min stirring conditions. After the addition is completed, the temperature is raised to 22.5°C and stirring is continued for 22 hours to prepare methacryloyl hydroxamic acid; methacryloyl hydroxamic acid and dichloromethane are mixed. The alkane was mixed uniformly at a mass ratio of 1:15, and a 9% sodium hydroxide aqueous solution with a mass fraction of 5.5 times the mass of methacryloyl hydroxamic acid was added at a uniform rate within 12 minutes under the stirring condition of 15°C and 150r / min. After the addition was completed, stirring was continued for 10 minutes, and then acetic anhydride with a mass fraction of 1.05 times the mass of methacryloyl hydroxamic acid was added, and stirring was continued for 22 hours. The mixture was washed with pure water and dichloromethane for 4 times, and the organic phase was taken after standing and stratification, and dried at 25°C and 75Pa for 3.5 hours to obtain a photothermal response monomer;

[0060] (2) Methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, soybean plant protein peptide with a molecular weight of 4000Da, and pure water are mixed in a mass ratio of 1:1:1:1:0.25:9 to prepare a monomer mixed emulsion; azobisisobutyronitrile and pure water are mixed in a mass ratio of 1:19 to prepare a thermal initiation solution; soybean plant protein peptide with a molecular weight of 4000Da and pure water are mixed in a mass ratio of 1:25 as a reaction base liquid, and under stirring conditions of 60°C and 400r / min, a monomer mixed emulsion with a mass of 1.5 times that of the reaction base liquid and a thermal initiation solution with a mass of 0.75 times that of the reaction base liquid are simultaneously added dropwise within 90 minutes. After the addition is completed, the temperature is kept unchanged and the reaction is continued for 11 hours, and the water content is concentrated to 41% at 35°C and 75Pa to obtain a polymer emulsion;

[0061] (3) Weigh 25 parts of PO42.5 ordinary Portland cement, 16 parts of polymer emulsion, 6 parts of pure water, 2.5 parts of allyl triethoxysilane, 2.5 parts of 3-aminopropyl triethoxysilane, and 0.15 parts of potassium persulfate according to their mass proportions; mix PO42.5 ordinary Portland cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 25° C. and 700 r / min for 3.5 min, then add acrylic emulsion and continue stirring for 25 min to prepare an exterior wall coating with strong adhesion.

[0062] Effect example

[0063] Table 1 below shows the performance analysis results of the compressive and corrosion resistance properties of the exterior wall coatings with strong bonding strength of Examples 1 to 3 of the present invention and Comparative Examples 1 to 3.

[0064] Table 1

[0065]

[0066]

[0067] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 1, it can be found that the exterior wall coating with strong bonding strength prepared by the present invention has good bonding performance and corrosion resistance.

[0068] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 1, it can be found that Examples 1, 2, and 3 have higher adhesion and lower corrosion than Comparative Example 1, which illustrates that the use of photothermal responsive monomers in the copolymerization during the preparation of the polymer emulsion allows the copolymer to undergo a Lossen rearrangement reaction under the action of cement hydration heat or sunlight exposure to generate isocyanate groups, which can react with the hydroxyl groups introduced by the copolymerization of hydroxyethyl methacrylate, or with the amino and carboxyl groups contained in other components to form a cross-linked network structure, making the structure more stable and dense, thereby improving the bonding performance and corrosion resistance; From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 2, it can be found that Examples 1, 2, and 3 have higher adhesion and lower corrosion than Comparative Example 2, which illustrates that By using 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane, the prepared modified plant protein peptide contains a large number of carbon-carbon double bonds, which can be polymerized by free radical unsaturated bonds under the initiation of potassium persulfate, and the Lossen rearrangement works together to form a double cross-linked network, further improving the bonding performance and corrosion resistance. From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 3, it can be found that Examples 1, 2, 3 have higher adhesion and lower corrosion than Comparative Example 3, which shows that the plant protein peptide is modified to make one end of the plant protein peptide hydrophilic and the other end hydrophobic, and has good emulsification and wetting effects, so that the organic components and inorganic components in the whole are mixed and dispersed more evenly, thereby improving the bonding performance and corrosion resistance.

[0069] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.

Claims

1. An exterior wall coating with strong bonding strength, characterized in that: Calculated by mass, it mainly includes: 20-30 parts of cement, 14-18 parts of polymer emulsion, 5-7 parts of pure water, 2-3 parts of allyltriethoxysilane, 2-3 parts of 3-aminopropyltriethoxysilane, and 0.1-0.2 parts of potassium persulfate.

2. The exterior wall paint with strong bonding strength according to claim 1, characterized in that: The polymer emulsion is prepared by free radical-initiated polymerization of methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate and photothermal response monomers and emulsification through modified plant protein peptides.

3. The exterior wall paint with strong bonding force according to claim 2, characterized in that: The photothermal response monomer is prepared by reacting hydroxylamine hydrochloride with methyl methacrylate and then reacting with acetic anhydride.

4. The exterior wall paint with strong bonding strength according to claim 2, characterized in that: The modified plant protein peptide is prepared by reacting 3-aminopropyl pentamethyldisiloxane with 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane, and then reacting with glutaraldehyde to obtain aldehyded polysiloxane; and reacting the aldehyded polysiloxane with the plant protein peptide to obtain the modified plant protein peptide.

5. A method for preparing an exterior wall coating with strong bonding strength, characterized in that: The preparation process mainly includes the following steps: (1) Methacryloyl hydroxamic acid and dichloromethane are mixed uniformly in a mass ratio of 1:14-16, and under the stirring conditions of 100-200 r / min at 10-20° C., an 8-10% sodium hydroxide aqueous solution with a mass fraction of 5-6 times the mass of the methacryloyl hydroxamic acid is added at a uniform rate within 10-15 minutes. After the addition is completed, stirring is continued for 8-12 minutes, and then acetic anhydride with a mass of 1-1.1 times the mass of the methacryloyl hydroxamic acid is added, and stirring is continued for 20-24 hours. The mixture is washed with a mixture of pure water and dichloromethane for 3-5 times, and after standing and stratification, the organic phase is taken and dried at 20-30° C. and 50-100 Pa for 3-4 hours to obtain a photothermal response monomer; (2) The amino-terminated polysiloxane, glutaraldehyde, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly at a mass ratio of 1:1:0.1-0.2:6-8:6-8, ultrasonically reacted at 75-85°C and 25-35kHz for 3-5 hours, and dried at 40-50°C and 10-50Pa for 8-10 hours to obtain the aldehyded polysiloxane; the plant protein peptide, aldehyded polysiloxane, acetic acid, anhydrous ethanol, and n-heptane are mixed uniformly at a mass ratio of 1:0.6-0.7:0.08-0.1:4-6:4-6, ultrasonically reacted at 75-85°C and 25-35kHz for 3-5 hours, and dried at 40-50°C and 10-50Pa for 8-10 hours to obtain the modified plant protein peptide; (3) The modified plant protein peptide and pure water are mixed uniformly in a mass ratio of 1:20-30 as a reaction base liquid, and a monomer mixed emulsion with a mass of 1.4-1.6 times the mass of the reaction base liquid and a thermal initiation solution with a mass of 0.7-0.8 times the mass of the reaction base liquid are added dropwise at 60°C and 300-500 r / min for 80-100 minutes. After the addition is completed, the temperature is kept unchanged and the reaction is continued for 10-12 hours. The polymer emulsion is concentrated at 30-40°C and 50-100 Pa to a water content of 40-42%, thereby obtaining a polymer emulsion; (4) Weigh 20 to 30 parts of cement, 14 to 18 parts of polymer emulsion, 5 to 7 parts of pure water, 2 to 3 parts of allyl triethoxysilane, 2 to 3 parts of 3-aminopropyl triethoxysilane, and 0.1 to 0.2 parts of potassium persulfate according to their mass fractions; mix the cement, allyl triethoxysilane, 3-aminopropyl triethoxysilane, potassium persulfate, and pure water, and stir at 20 to 30° C. and 600 to 800 r / min for 3 to 4 minutes, then add the acrylic emulsion and continue stirring for 20 to 30 minutes to obtain an exterior wall coating with strong adhesion.

6. The method for preparing an exterior wall coating with strong bonding force according to claim 5, characterized in that: The preparation method of the methacryloyl hydroxamic acid in step (1) is as follows: methyl methacrylate and methanol are mixed uniformly at a mass ratio of 1:4-6 to prepare a methyl methacrylate solution; hydroxylamine hydrochloride, sodium hydroxide and pure water are mixed uniformly at a mass ratio of 1:1.1-1.3:6-8 in a nitrogen atmosphere, and the methyl methacrylate solution with a mass of 5 to 7 times that of hydroxylamine hydrochloride is added at a uniform speed within 20 to 25 minutes at a stirring condition of 0 to 5° C. and 100 to 200 r / min, and after the addition is completed, the temperature is raised to 20 to 25° C. and the stirring is continued for 20 to 24 hours to prepare the methacrylic acid.

7. The method for preparing an exterior wall coating with strong bonding force according to claim 5, characterized in that: The preparation method of the amino-terminated polysiloxane in step (2) is as follows: 3-aminopropyl pentamethyldisiloxane and 2,4-divinyl-2,4,6,6,8,8-hexamethylcyclotetrasiloxane are uniformly mixed in a mass ratio of 1:3 to 1:4, and then 0.1 to 0.2 times the mass of 3-aminopropyl pentamethyldisiloxane is added with concentrated sulfuric acid of 98% by mass, and the mixture is stirred at 80 to 90° C. and 800 to 1000 r / min for 2 to 3 hours. After cooling to room temperature, calcium hydroxide is added to adjust the pH to 6 to 7, and the mixture is washed 3 to 5 times with a mixture of pure water and n-heptane in a volume ratio of 1:1, and the oil phase is taken out after standing for stratification, and dried at 40 to 50° C. and 10 to 50 Pa for 8 to 10 hours to prepare the polysiloxane.

8. The method for preparing an exterior wall coating with strong bonding force according to claim 5, characterized in that: The plant protein peptide in step (2) is a mixture of one or more of soybean plant protein peptide, corn plant protein peptide, peanut plant protein peptide and wheat plant protein peptide, and has a molecular weight of 3000 to 5000 Da.

9. The method for preparing an exterior wall coating with strong bonding force according to claim 5, characterized in that: The monomer mixed emulsion in step (3) is prepared by uniformly mixing methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, photothermal response monomer, modified plant protein peptide and pure water in a mass ratio of 1:1:1:1:0.2-0.3:8-10; the thermal initiation solution is prepared by uniformly mixing azobisisobutyronitrile and pure water in a mass ratio of 1:18-20.

10. The method for preparing an exterior wall coating with strong bonding force according to claim 5, characterized in that: The cement in step (4) is one or a mixture of silicate cement, ordinary silicate cement, slag silicate cement, pozzolanic silicate cement, fly ash silicate cement, and composite silicate cement.

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