阅读说明：本技术 一种高柔性聚合物水泥基防水涂料的制备方法 (Preparation method of high-flexibility polymer cement-based waterproof coating ) 是由 赵朵 于 2021-01-15 设计创作，主要内容包括：本发明涉及一种高柔性聚合物水泥基防水涂料的制备方法,属于建筑涂料技术领域。本发明以苯乙烯、丙烯酸脂单体和双酚A型环氧树脂为原料,通过预乳化聚合工艺,制备环氧改性苯丙乳液,以环氧树脂为原料制备的涂料固化收缩率低,固化后涂层中含有致密物,具有良好的耐水性,本发明通过添加甲基丙烯酰氧基三甲氧基硅烷微胶囊和滑石粉,制备高柔性聚合物水泥基防水涂料,滑石粉是片状和纤维状两种结构形态的混合物,能对涂膜的机械性起到增强作用,增加柔韧性,提升涂膜的耐水性,甲基丙烯酰氧基三甲氧基硅烷中的直链烷基具有一定柔性,不仅能增强防水涂料的拉伸强度,同时也能松弛界面之间的应力,提高涂料的柔性和断裂伸长率。(The invention relates to a preparation method of a high-flexibility polymer cement-based waterproof coating, belonging to the technical field of building coatings. The invention takes styrene, acrylate monomer and bisphenol A type epoxy resin as raw materials, the epoxy modified styrene-acrylic emulsion is prepared by a pre-emulsification polymerization process, the coating prepared by taking the epoxy resin as the raw material has low curing shrinkage, and the cured coating contains compact substances and has good water resistance.)

1. A preparation method of a high-flexibility polymer cement-based waterproof coating is characterized by comprising the following specific preparation steps:

(1) adding deionized water, sodium stearate, polydimethylsiloxane and dodecyl alcohol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion in a high-speed stirrer, and stirring at the normal temperature at the rotating speed of 1200-1600 r/min for 20-30 min to obtain a mixed liquid material;

(2) placing portland cement, methacryloxy trimethoxy silane microcapsules, heavy calcium carbonate powder, talcum powder, quartz sand and a modified polycarboxylic acid water reducing agent into a stirrer, and stirring at the normal temperature at the rotating speed of 400-500 r/min for 30-40 min to obtain mixed powder;

(3) and adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 1 to 2 hours at the normal temperature at the rotating speed of 2000 to 2500r/min to obtain the high-flexibility polymer cement-based waterproof coating.

2. The preparation method of the high-flexibility polymer cement-based waterproof coating material as claimed in claim 1, wherein the epoxy modified styrene-acrylic emulsion, the portland cement, the methacryloxy trimethoxy silane microcapsule, the kaolin, the mica powder, the quartz sand, the modified polycarboxylic acid water reducing agent, the sodium stearate, the polydimethylsiloxane, the lauryl alcohol ester and the deionized water are respectively 100-120 parts by weight of the epoxy modified styrene-acrylic emulsion, 50-60 parts by weight of the portland cement, 10-12 parts by weight of the methacryloxy trimethoxy silane microcapsule, 20-24 parts by weight of the kaolin, 20-24 parts by weight of the mica powder, 10-12 parts by weight of the quartz sand, 0.5-0.6 part by weight of the polycarboxylic acid water reducing agent, 0.5-0.6 part by weight of the sodium stearate, 0.2-0.3 part by weight of the polydimethylsiloxane, 0.2-0.3 part by weight of the lauryl alcohol ester and 40-48 parts by weight of.

3. The preparation method of the high-flexibility polymer cement-based waterproof coating as claimed in claim 1, wherein the specific preparation steps of the epoxy modified styrene-acrylic emulsion in the step (1) are as follows:

(1) adding styrene, methyl methacrylate, n-butyl acrylate and acrylic acid into bisphenol A epoxy resin, and stirring at the rotating speed of 160-180 r/min for 10-15 min at normal temperature to obtain a mixed monomer;

(2) adding sodium dodecyl sulfate and octyl phenol polyoxyethylene ether into 1/3 mass of deionized water, stirring for 20-30 min at a rotating speed of 180-200 r/min under a water bath condition of 40-50 ℃, and preserving heat to obtain an emulsifier solution;

(3) adding the mixed monomer into an emulsifier solution, and stirring for 1-2 hours at a rotating speed of 200-240 r/min under a water bath condition of 40-50 ℃ to obtain a pre-emulsion;

(4) adding sodium bicarbonate into 1/3 mass deionized water, and stirring at the normal temperature at the rotating speed of 140-160 r/min for 15-20 min to obtain a sodium bicarbonate solution;

(5) adding a sodium bicarbonate solution and hydroquinone into the pre-emulsion, and stirring for 1-2 hours at a rotating speed of 240-280 r/min under a water bath condition of 30-40 ℃ to obtain a mixed emulsion;

(6) adding ammonium persulfate into the residual 1/3 mass of deionized water, and stirring at the normal temperature at the rotating speed of 180-200 r/min for 12-16 min to obtain an ammonium persulfate solution;

(7) slowly adding an ammonium persulfate solution into the mixed emulsion, stirring and reacting for 1-2 h at a rotating speed of 220-260 r/min under a water bath condition of 80-90 ℃, cooling to 50-60 ℃, adjusting the pH value to 7-8, and cooling at normal temperature to obtain the epoxy modified styrene-acrylic emulsion.

4. The preparation method of the high-flexibility polymer cement-based waterproof coating as claimed in claim 3, wherein the weight parts of styrene, methyl methacrylate, n-butyl acrylate, acrylic acid, bisphenol A epoxy resin, hydroquinone, sodium dodecyl sulfate, polyoxyethylene octylphenol ether, ammonium persulfate, sodium bicarbonate and deionized water are respectively 30-40 parts of styrene, 15-20 parts of methyl methacrylate, 18-24 parts of n-butyl acrylate, 12-16 parts of acrylic acid, 30-40 parts of bisphenol A epoxy resin, 3-4 parts of hydroquinone, 0.6-0.8 part of sodium dodecyl sulfate, 0.6-0.8 part of polyoxyethylene octylphenol ether, 0.3-0.4 part of ammonium persulfate, 6-8 parts of sodium bicarbonate and 180-240 parts of deionized water.

5. The preparation method of the high-flexibility polymer cement-based waterproof coating material as claimed in claim 3, wherein the dropping rate of the ammonium persulfate solution in the step (6) is 20-30 mL/min, and ammonia water with a mass fraction of 1% is used for pH adjustment.

6. The method for preparing the high-flexibility polymer cement-based waterproof coating according to claim 1, wherein the methacryloxy trimethoxy silane microcapsule of the step (2) is prepared by the following steps:

(1) adding maltodextrin and polyvinylpyrrolidone into deionized water, placing the mixture into an ultrasonic dispersion machine, and ultrasonically dissolving the mixture for 20-30 min at the temperature of 30-40 ℃ to obtain a composite wall material solution;

(2) adding methacryloxy trimethoxy silane into the composite wall material solution, placing the solution in a high-speed stirrer, and stirring the solution at the normal temperature at the rotating speed of 3500-4500 r/min for 5-10 min to obtain an emulsion;

(3) putting the emulsion in a spray dryer, introducing nitrogen for protection, and carrying out atomization drying at the rotating speed of 22000-24000 r/min to obtain solid powder;

(4) and (3) cooling the solid powder for 10-12 h at room temperature to obtain the methacryloxy trimethoxy silane microcapsule.

7. The preparation method of the high-flexibility polymer cement-based waterproof coating as claimed in claim 6, wherein the weight parts of the maltodextrin, the polyvinylpyrrolidone, the methacryloxy trimethoxysilane and the deionized water are respectively 20-40 parts of the maltodextrin, 5-10 parts of the polyvinylpyrrolidone, 8-16 parts of the methacryloxy trimethoxysilane and 60-120 parts of the deionized water.

8. The preparation method of the high-flexibility polymer cement-based waterproof coating material as claimed in claim 6, wherein the ultrasonic dissolving power in the step (1) is 300-400W.

9. The preparation method of the high-flexibility polymer cement-based waterproof coating as claimed in claim 6, wherein the conditions of the atomization drying in the step (3) are that the inlet temperature is 160-180 ℃ and the outlet temperature is 80-100 ℃.

10. The preparation method of the high-flexibility polymer cement-based waterproof coating material as claimed in claim 1, wherein the preparation method of the modified polycarboxylate superplasticizer in step (2) comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 1-2 parts, lactic acid: 3-5 parts of sulfamic acid: 4-8 parts of deionized water: 5-10 parts of a solvent, stirring for dissolving, and uniformly mixing to obtain a solution A; the chain transfer agent is any one of mercaptoethanol and dodecyl mercaptan;

preparing solution B: respectively adding potassium permanganate: 1-2 parts of unsaturated polyether: 3-6 parts of deionized water: 5-10 parts of a solvent, and uniformly stirring and mixing to obtain a solution B; the unsaturated polyether is one of nonylphenyl polyoxyethylene ether (NP) or methyl enol polyoxyethylene ether (TPEG);

thirdly, adding the solution B into the reactor, heating to 60-75 ℃, dropwise adding the solution A under the stirring condition of 100-300 r/min at the dropwise adding speed of 8-24 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 2-5h after dropwise adding, cooling to room temperature after the reaction is finished, and adjusting the pH value to 7.8-8.6 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

Technical Field

The invention relates to a preparation method of a high-flexibility polymer cement-based waterproof coating, belonging to the technical field of building coatings.

Background

The building waterproof is an important component in building engineering, is one of main functions of buildings, and is an important process for ensuring that the buildings are not damaged. Leakage is a common quality problem that exists notably in existing projects. If a user finds leakage in the using process, the building wall body can be peeled off, becomes mildewed and smells, and causes an unwearing psychological shadow for residents. Since the waterproof materials for construction are the foundation of waterproof engineering, the development of waterproof materials for construction is indispensable for promoting the progress of construction industry.

At present, waterproof materials on the market mainly have three main types: waterproof coiled materials, polyurethane waterproof coatings and polymer cement-based waterproof coatings. The polymer cement-based waterproof coating is prepared by mixing emulsion synthesized by various aqueous high-molecular polymers and cement doped with a filler and an additive. The cement-based waterproof material has good durability and good bonding performance with a base layer, but belongs to a rigid material which is not suitable for a part with large deformation; the high molecular polymer flexible waterproof material has various types and varieties, can adapt to various deformations, but has the defects of poor compatibility with a base layer and easy aging. The flexibility of the high molecular polymer and the rigidity of the cement are integrated, so that the cement composite material overcomes the defects of the high molecular polymer and the cement, has two advantages, and improves the impermeability and stability of a system. The method has the advantages of environmental protection, low comprehensive cost, convenient construction and short construction period. Therefore, polymer cement-based waterproof coatings have become the most commonly used waterproof materials

In engineering application, the problems of easy cracking, insufficient flexibility and the like of a coating formed by the polymer cement-based waterproof coating are found. In order to improve the application effect and the service performance of the waterproof coating, a method for blocking a water seepage channel by adding a waterproof agent is generally adopted at present, which is beneficial to making up the defects of the waterproof coating; but the method has no influence on the internal structure of the material, so the effect is poor. Therefore, the research and development of waterproof coatings with better performance and higher flexibility have practical significance.

Disclosure of Invention

The technical problems to be solved by the invention are as follows: aiming at the problems of easy cracking and insufficient flexibility of a coating formed by a common polymer cement-based waterproof coating, the preparation method of the high-flexibility polymer cement-based waterproof coating is provided.

In order to solve the technical problems, the invention adopts the technical scheme that:

(1) adding deionized water, sodium stearate, polydimethylsiloxane and dodecyl alcohol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion in a high-speed stirrer, and stirring at the normal temperature at the rotating speed of 1200-1600 r/min for 20-30 min to obtain a mixed liquid material;

(2) placing portland cement, methacryloxy trimethoxy silane microcapsules, kaolin powder, mica powder, quartz sand and a modified polycarboxylic acid water reducing agent into a stirrer, and stirring at the normal temperature at the rotating speed of 400-500 r/min for 30-40 min to obtain mixed powder;

(3) and adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 1 to 2 hours at the normal temperature at the rotating speed of 2000 to 2500r/min to obtain the high-flexibility polymer cement-based waterproof coating.

The epoxy modified styrene-acrylic emulsion, the portland cement, the methacryloxy trimethoxy silane microcapsule, the kaolin powder, the mica powder, the quartz sand, the modified polycarboxylic acid water reducing agent, the sodium stearate, the polydimethylsiloxane, the dodecyl alcohol ester and the deionized water are respectively in parts by weight: 100-120 parts of epoxy modified styrene-acrylic emulsion, 50-60 parts of portland cement, 10-12 parts of methacryloxy trimethoxy silane microcapsule, 20-24 parts of kaolin powder, 20-24 parts of mica powder, 10-12 parts of quartz sand, 0.5-0.6 part of modified polycarboxylic acid water reducing agent, 0.5-0.6 part of sodium stearate, 0.2-0.3 part of polydimethylsiloxane, 0.2-0.3 part of dodecyl alcohol ester and 40-48 parts of deionized water.

The specific preparation steps of the epoxy modified styrene-acrylic emulsion in the step (1) are as follows:

(1) adding styrene, methyl methacrylate, n-butyl acrylate and acrylic acid into bisphenol A epoxy resin, and stirring at the rotating speed of 160-180 r/min for 10-15 min at normal temperature to obtain a mixed monomer;

(2) adding sodium dodecyl sulfate and octyl phenol polyoxyethylene ether into 1/3 mass of deionized water, stirring for 20-30 min at a rotating speed of 180-200 r/min under a water bath condition of 40-50 ℃, and preserving heat to obtain an emulsifier solution;

(3) adding the mixed monomer into an emulsifier solution, and stirring for 1-2 hours at a rotating speed of 200-240 r/min under a water bath condition of 40-50 ℃ to obtain a pre-emulsion;

(4) adding sodium bicarbonate into 1/3 mass deionized water, and stirring at the normal temperature at the rotating speed of 140-160 r/min for 15-20 min to obtain a sodium bicarbonate solution;

(5) adding a sodium bicarbonate solution and hydroquinone into the pre-emulsion, and stirring for 1-2 hours at a rotating speed of 240-280 r/min under a water bath condition of 30-40 ℃ to obtain a mixed emulsion;

(6) adding ammonium persulfate into the residual 1/3 mass of deionized water, and stirring at the normal temperature at the rotating speed of 180-200 r/min for 12-16 min to obtain an ammonium persulfate solution;

(7) slowly adding an ammonium persulfate solution into the mixed emulsion, stirring and reacting for 1-2 h at a rotating speed of 220-260 r/min under a water bath condition of 80-90 ℃, cooling to 50-60 ℃, adjusting the pH value to 7-8, and cooling at normal temperature to obtain the epoxy modified styrene-acrylic emulsion.

The weight parts of the styrene, the methyl methacrylate, the n-butyl acrylate, the acrylic acid, the bisphenol A epoxy resin, the hydroquinone, the sodium dodecyl sulfate, the octyl phenol polyoxyethylene ether, the ammonium persulfate, the sodium bicarbonate and the deionized water are respectively as follows: 30-40 parts of styrene, 15-20 parts of methyl methacrylate, 18-24 parts of n-butyl acrylate, 12-16 parts of acrylic acid, 30-40 parts of bisphenol A epoxy resin, 3-4 parts of hydroquinone, 0.6-0.8 part of sodium dodecyl sulfate, 0.6-0.8 part of octyl phenol polyoxyethylene ether, 0.3-0.4 part of ammonium persulfate, 6-8 parts of sodium bicarbonate and 180-240 parts of deionized water.

And (3) dropwise adding the ammonium persulfate solution in the step (6) at a rate of 20-30 mL/min, and adjusting the pH by using ammonia water with a mass fraction of 1%.

The specific preparation steps of the methacryloxy trimethoxy silane microcapsule in the step (2) are as follows:

(1) adding maltodextrin and polyvinylpyrrolidone into deionized water, placing the mixture into an ultrasonic dispersion machine, and ultrasonically dissolving the mixture for 20-30 min at the temperature of 30-40 ℃ to obtain a composite wall material solution;

(2) adding methacryloxy trimethoxy silane into the composite wall material solution, placing the solution in a high-speed stirrer, and stirring the solution at the normal temperature at the rotating speed of 3500-4500 r/min for 5-10 min to obtain an emulsion;

(3) putting the emulsion in a spray dryer, introducing nitrogen for protection, and carrying out atomization drying at the rotating speed of 22000-24000 r/min to obtain solid powder;

(4) and (3) cooling the solid powder for 10-12 h at room temperature to obtain the methacryloxy trimethoxy silane microcapsule.

The maltodextrin, the polyvinylpyrrolidone, the methacryloxy trimethoxy silane and the deionized water are respectively in parts by weight: 20-40 parts of maltodextrin, 5-10 parts of polyvinylpyrrolidone, 8-16 parts of methacryloxy trimethoxy silane and 60-120 parts of deionized water.

The power of ultrasonic dissolution in the step (1) is 300-400W.

The conditions of the atomization drying in the step (3) are that the inlet temperature is 160-180 ℃, and the outlet temperature is 80-100 DEG C

The preparation method of the modified polycarboxylic acid water reducing agent comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 1-2 parts, lactic acid: 3-5 parts of sulfamic acid: 4-8 parts of deionized water: 5-10 parts of a solvent, stirring for dissolving, and uniformly mixing to obtain a solution A; the polymerization chain transfer agent is any one of mercaptoethanol and dodecyl mercaptan;

preparing solution B: respectively adding potassium permanganate: 1-2 parts of unsaturated polyether: 3-6 parts of deionized water: 5-10 parts of a solvent, and uniformly stirring and mixing to obtain a solution B; the unsaturated polyether is one of nonylphenyl polyoxyethylene ether (NP) or methyl enol polyoxyethylene ether (TPEG).

And adding the solution B into a reactor, heating to 60-75 ℃, dropwise adding the solution A under the stirring condition of 100-300 r/min at the dropwise adding speed of 8-24 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 2-5h after dropwise adding, cooling to room temperature after the reaction is finished, and adjusting the pH value to 7.8-8.6 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

Compared with other methods, the method has the beneficial technical effects that:

(1) the invention takes styrene, acrylate monomer and bisphenol A type epoxy resin as raw materials, and prepares epoxy modified styrene-acrylic emulsion for high-flexibility polymer cement-based waterproof coating through a pre-emulsification polymerization process, the structure of the epoxy resin contains extremely active epoxy group, ether bond and hydroxyl group, the epoxy group can form chemical bond with the polymer surface in the styrene-acrylic emulsion, and the hydroxyl group and the ether bond have extremely high polarity, so that the epoxy resin and an adjacent interface generate electromagnetic suction, and the adhesiveness of the waterproof coating can be effectively improved, the curing reaction of the epoxy resin is mainly epoxy ring-opening addition curing, no bubble or small molecular substance is generated in the curing process, the coating prepared by taking the epoxy resin as the raw material has low curing shrinkage, the cured coating contains compact substances of benzene ring, ether bond and three-dimensional cross-linked structure, and has good chemical stability, The epoxy resin is utilized to modify the styrene-acrylic emulsion, so that the film-forming property of the emulsion, the adhesive force of a coating film and the water resistance can be obviously improved, and the service life of the high-flexibility polymer cement-based waterproof coating can be effectively prolonged;

(2) the invention prepares a high-flexibility polymer cement-based waterproof coating by adding methacryloxy trimethoxy silane microcapsule and mica powder, wherein the mica powder is a white powdery substance prepared by selecting, crushing and grinding talc, talcite, saponite, asbestos chlorite, fibrous talc and other minerals, the white powdery substance is a mixture of two structural forms of sheet and fiber, the fibrous structure can enhance the mechanical property of a coating film and increase the flexibility, the sheet structure can prevent the permeation of water and improve the water resistance of the coating film, the wall material of the methacryloxy trimethoxy silane microcapsule is hydrophilic polyvinylpyrrolidone and maltodextrin, after the two components of the waterproof coating are mixed, the wall material can be quickly dissolved in water to release the methacryloxy trimethoxy silane, and when the methacryloxy trimethoxy silane meets water, the hydrolysis reaction can occur, hydrolysis forms silanol bonds, dehydration condensation reaction is carried out among partial silanol bonds to form oligosiloxane, the rest silanol bonds react with hydroxyl on the surface of fillers such as mica powder to form hydrogen bonds, the oligosiloxane further dehydrates and forms covalent bond connection with the fillers along with continuous reduction of water in a system, so that combination between the fillers and an interpenetrating network of an emulsion film is firmer, a film of the waterproof coating becomes more compact, and linear alkyl in methacryloxy trimethoxy silane has certain flexibility, so that the tensile strength of the waterproof coating can be enhanced under the action of the methacryloxy trimethoxy silane, stress among interfaces can be relaxed, and the flexibility and elongation at break of the coating are improved.

Detailed Description

Respectively weighing 30-40 parts of styrene, 15-20 parts of methyl methacrylate, 18-24 parts of n-butyl acrylate, 12-16 parts of acrylic acid, 30-40 parts of bisphenol A epoxy resin, 3-4 parts of hydroquinone, 0.6-0.8 part of sodium dodecyl sulfate, 0.6-0.8 part of octyl phenol polyoxyethylene ether, 0.3-0.4 part of ammonium persulfate, 6-8 parts of sodium bicarbonate and 180-240 parts of deionized water according to parts by weight, adding the styrene, the methyl methacrylate, the n-butyl acrylate and the acrylic acid into the bisphenol A epoxy resin, stirring at the rotating speed of 160-180 r/min for 10-15 min at normal temperature to obtain a mixed monomer, adding the sodium dodecyl sulfate and the octyl phenol polyoxyethylene ether into 1/3 mass parts of deionized water, stirring at the rotating speed of 180-200 r/min under the water bath condition of 40-50 ℃ for 20-30 min, preserving heat to obtain an emulsifier solution, adding a mixed monomer into an emulsifier solution, stirring for 1-2 hours at a rotating speed of 200-240 r/min under a water bath condition of 40-50 ℃ to obtain a pre-emulsion, adding sodium bicarbonate into 1/3 mass deionized water, stirring for 15-20 minutes at a rotating speed of 140-160 r/min at normal temperature to obtain a sodium bicarbonate solution, adding the sodium bicarbonate solution and hydroquinone into the pre-emulsion, stirring for 1-2 hours at a rotating speed of 240-280 r/min under a water bath condition of 30-40 ℃ to obtain a mixed emulsion, adding ammonium persulfate into the rest 1/3 mass deionized water, stirring for 12-16 minutes at a rotating speed of 180-200 r/min at normal temperature to obtain an ammonium persulfate solution, slowly adding the ammonium persulfate solution into the mixed emulsion at a dropping speed of 20-30 mL/min, stirring and reacting for 1-2 hours at a rotating speed of 220-260 r/min under a water bath condition of 80-90 ℃, cooling to 50-60 ℃, dropwise adding ammonia water with the mass fraction of 1% to adjust the pH value to 7-8, and cooling at normal temperature to obtain epoxy modified styrene-acrylic emulsion;

respectively weighing 20-40 parts of maltodextrin, 5-10 parts of polyvinylpyrrolidone, 8-16 parts of methacryloxy trimethoxy silane and 60-120 parts of deionized water according to parts by weight, adding the maltodextrin and the polyvinylpyrrolidone into the deionized water, placing the mixture into an ultrasonic dispersion machine, ultrasonically dissolving the mixture for 20-30 min at the temperature of 30-40 ℃ with the power of 300-400W to obtain a composite wall material solution, adding the methacryloxy trimethoxy silane into the composite wall material solution, placing the mixture into a high-speed stirring machine, stirring the mixture for 5-10 min at the normal temperature at the rotating speed of 3500-4500 r/min to obtain an emulsion, placing the emulsion into a spray drying machine, introducing nitrogen for protection, carrying out atomization drying at the inlet temperature of 160-180 ℃ and the outlet temperature of 80-100 ℃ at the rotating speed of 22000-24000 r/min to obtain solid powder, placing the solid powder at the room temperature for cooling for 10-12 h, obtaining methacryloxy trimethoxy silane microcapsules;

then, respectively weighing 100-120 parts of epoxy modified styrene-acrylic emulsion, 50-60 parts of portland cement, 10-12 parts of methacryloxy trimethoxy silane microcapsule, 20-24 parts of kaolin powder, 20-24 parts of mica powder, 10-12 parts of quartz sand, 0.5-0.6 part of modified polycarboxylic acid water reducer, 0.5-0.6 part of sodium stearate, 0.2-0.3 part of polydimethylsiloxane, 0.2-0.3 part of dodecanol ester and 40-48 parts of deionized water according to parts by weight, adding deionized water, sodium stearate, polydimethylsiloxane and dodecanol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion into a high-speed stirrer, stirring at the normal temperature at the rotating speed of 1200-1600 r/min for 20-30 min to obtain a mixed liquid material, placing the portland cement, the methacryloxy trimethoxy silane microcapsule, the kaolin powder, the mica powder, the quartz sand and the modified polycarboxylic acid into a stirrer, stirring the mixture for 30-40 min at the rotating speed of 400-500 r/min at normal temperature to obtain mixed powder, adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 1-2 h at the rotating speed of 2000-2500 r/min at normal temperature to obtain the high-flexibility polymer cement-based waterproof coating.

The preparation method of the modified polycarboxylic acid water reducing agent comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 1-2 parts, lactic acid: 3-5 parts of sulfamic acid: 4-8 parts of deionized water: 5-10 parts of a solvent, stirring for dissolving, and uniformly mixing to obtain a solution A; the polymerization chain transfer agent is any one of mercaptoethanol and dodecyl mercaptan;

preparing solution B: respectively adding potassium permanganate: 1-2 parts of unsaturated polyether: 3-6 parts of deionized water: 5-10 parts of a solvent, and uniformly stirring and mixing to obtain a solution B; the unsaturated polyether is one of nonylphenyl polyoxyethylene ether (NP) or methyl enol polyoxyethylene ether (TPEG).

And adding the solution B into a reactor, heating to 60-75 ℃, dropwise adding the solution A under the stirring condition of 100-300 r/min at the dropwise adding speed of 8-24 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 2-5h after dropwise adding, cooling to room temperature after the reaction is finished, and adjusting the pH value to 7.8-8.6 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

Example 1

Respectively weighing 30 parts of styrene, 15 parts of methyl methacrylate, 18 parts of n-butyl acrylate, 12 parts of acrylic acid, 30 parts of bisphenol A epoxy resin, 3 parts of hydroquinone, 0.6 part of sodium dodecyl sulfate, 0.6 part of octyl phenol polyoxyethylene ether, 0.3 part of ammonium persulfate, 6 parts of sodium bicarbonate and 180 parts of deionized water according to parts by weight, adding the styrene, the methyl methacrylate, the n-butyl acrylate and the acrylic acid into the bisphenol A epoxy resin, stirring at the rotating speed of 160r/min for 10min at normal temperature to obtain a mixed monomer, adding the sodium dodecyl sulfate and the octyl phenol polyoxyethylene ether into 1/3 mass of deionized water, stirring at the rotating speed of 180r/min for 20min under the water bath condition of 40 ℃, preserving heat to obtain an emulsifier solution, adding the mixed monomer into the emulsifier solution, stirring at the rotating speed of 200r/min for 1h under the water bath condition of 40 ℃, adding sodium bicarbonate into deionized water of 1/3 mass, stirring at 140r/min for 15min at normal temperature to obtain sodium bicarbonate solution, adding the sodium bicarbonate solution and hydroquinone into the pre-emulsion, stirring at 240r/min for 1h under the water bath condition of 30 ℃ to obtain mixed emulsion, adding ammonium persulfate into the rest 1/3 mass of deionized water, stirring at 180r/min for 12min at normal temperature to obtain ammonium persulfate solution, slowly adding the ammonium persulfate solution into the mixed emulsion at the dropping rate of 20mL/min, stirring at 220r/min for reaction for 1h under the water bath condition of 80 ℃, cooling to 50 ℃, dropping ammonia water of which the mass fraction is 1% to adjust the pH to 7, and cooling at normal temperature to obtain epoxy modified styrene-acrylic emulsion;

respectively weighing 20 parts of maltodextrin, 5 parts of polyvinylpyrrolidone, 8 parts of methacryloxy trimethoxy silane and 60 parts of deionized water according to parts by weight, adding the maltodextrin and the polyvinylpyrrolidone into the deionized water, placing the mixture in an ultrasonic dispersion machine, ultrasonically dissolving the mixture for 20min at the temperature of 30 ℃ with the power of 300W to obtain a composite wall material solution, adding methacryloxy trimethoxy silane into the composite wall material solution, placing in a high-speed stirrer, stirring at 3500-4500 r/min for 5min at normal temperature to obtain emulsion, placing the emulsion in a spray dryer, introducing nitrogen for protection, atomizing and drying at the rotating speed of 22000r/min under the conditions that the inlet temperature is 160 ℃ and the outlet temperature is 80 ℃ to obtain solid powder, and cooling the solid powder for 10 hours at room temperature to obtain methacryloxy trimethoxy silane microcapsules;

then respectively weighing 100 parts of epoxy modified styrene-acrylic emulsion, 50 parts of portland cement, 10 parts of methacryloxy trimethoxy silane microcapsule, 20 parts of kaolin powder, 20 parts of mica powder, 10 parts of quartz sand, 0.5 part of modified polycarboxylic acid water reducing agent, 0.5 part of sodium stearate, 0.2 part of polydimethylsiloxane, 0.2 part of dodecanol ester and 40 parts of deionized water, adding deionized water, sodium stearate, polydimethylsiloxane and dodecanol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion in a high-speed stirrer, stirring the epoxy modified styrene-acrylic emulsion for 20min at the normal temperature at the rotating speed of 1200r/min to obtain a mixed liquid material, placing the portland cement, methacryloxy trimethoxy silane microcapsule, the kaolin powder, the mica powder, the quartz sand and the modified polycarboxylic acid water reducing agent in a stirrer, stirring the mixed liquid material for 30min at the normal temperature at the rotating speed of 400r/min to obtain mixed powder material, and adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 1 hour at the normal temperature at the rotating speed of 2000r/min to obtain the high-flexibility polymer cement-based waterproof coating.

The preparation method of the modified polycarboxylic acid water reducing agent comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 1 part, lactic acid: 3 parts, sulfamic acid: 4 parts, deionized water: 5 parts of the raw materials are stirred, dissolved and uniformly mixed to obtain a solution A; the polymerization chain transfer agent is mercaptoethanol;

preparing solution B: respectively adding potassium permanganate: 1 part, unsaturated polyether: 3 parts of deionized water: 5 parts of the raw materials are stirred and mixed uniformly to obtain a solution B; the unsaturated polyether is nonylphenyl polyoxyethylene ether (NP).

And adding the solution B into a reactor, heating to 60 ℃, dropwise adding the solution A under the stirring condition of 100r/min at the dropping speed of 8 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 2 hours after the dropwise adding is finished, cooling to room temperature after the reaction is finished, and adjusting the pH value to 7.8 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

Example 2

Respectively weighing 35 parts of styrene, 17 parts of methyl methacrylate, 21 parts of n-butyl acrylate, 14 parts of acrylic acid, 35 parts of bisphenol A epoxy resin, 3.5 parts of hydroquinone, 0.7 part of sodium dodecyl sulfate, 0.7 part of octyl phenol polyoxyethylene ether, 0.35 part of ammonium persulfate, 7 parts of sodium bicarbonate and 210 parts of deionized water according to parts by weight, adding the styrene, the methyl methacrylate, the n-butyl acrylate and the acrylic acid into the bisphenol A epoxy resin, stirring at the rotating speed of 170r/min for 12.5min at normal temperature to obtain a mixed monomer, adding the sodium dodecyl sulfate and the octyl phenol polyoxyethylene ether into 1/3 mass of deionized water, stirring at the rotating speed of 190r/min for 25min under the water bath condition of 45 ℃, preserving heat to obtain an emulsifier solution, adding the mixed monomer into the emulsifier solution, stirring at the rotating speed of 220r/min for 1.5h under the water bath condition of 45 ℃, adding sodium bicarbonate into deionized water of 1/3 mass, stirring for 17min at the normal temperature at the rotating speed of 150r/min to obtain a sodium bicarbonate solution, adding the sodium bicarbonate solution and hydroquinone into the pre-emulsion, stirring for 1.5h at the rotating speed of 260r/min under the water bath condition of 35 ℃ to obtain a mixed emulsion, adding ammonium persulfate into the rest 1/3 mass of deionized water, stirring for 14min at the normal temperature at the rotating speed of 190r/min to obtain an ammonium sulfate solution, slowly adding the ammonium persulfate solution into the mixed emulsion at the dropping speed of 20-30 mL/min, stirring and reacting for 1.5h at the rotating speed of 240r/min under the water bath condition of 85 ℃, cooling to 55 ℃, dropping ammonia water of which the mass fraction is 1% to adjust the pH value to 7.5, and cooling at the normal temperature to obtain an epoxy modified styrene-acrylic emulsion;

then respectively weighing 30 parts of maltodextrin, 7 parts of polyvinylpyrrolidone, 12 parts of methacryloxy trimethoxy silane and 90 parts of deionized water according to parts by weight, adding the maltodextrin and the polyvinylpyrrolidone into the deionized water, placing the mixture in an ultrasonic dispersion machine, ultrasonically dissolving the mixture for 25min at the temperature of 35 ℃ and the power of 350W to obtain a composite wall material solution, adding methacryloxy trimethoxy silane into the composite wall material solution, placing in a high-speed stirrer, stirring at 4000r/min for 7min at normal temperature to obtain emulsion, placing the emulsion in a spray dryer, introducing nitrogen for protection, atomizing and drying at 23000r/min under the conditions of the inlet temperature of 170 ℃ and the outlet temperature of 90 ℃ to obtain solid powder, and cooling the solid powder at room temperature for 11h to obtain methacryloxy trimethoxy silane microcapsules;

then respectively weighing 110 parts of epoxy modified styrene-acrylic emulsion, 55 parts of portland cement, 11 parts of methacryloxy trimethoxy silane microcapsule, 22 parts of kaolin powder, 22 parts of mica powder, 10-12 parts of quartz sand, 0.55 part of modified polycarboxylic acid water reducing agent, 0.55 part of sodium stearate, 0.25 part of polydimethylsiloxane, 0.25 part of dodecanol ester and 44 parts of deionized water, adding deionized water, sodium stearate, polydimethylsiloxane and dodecanol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion in a high-speed stirrer, stirring at the rotating speed of 1400r/min for 25min at normal temperature to obtain a mixed liquid material, placing the portland cement, methacryloxy trimethoxy silane microcapsule, kaolin powder, mica powder, quartz sand and modified polycarboxylic acid water reducing agent in a stirrer, stirring at the rotating speed of 450r/min at normal temperature for 35min to obtain a mixed powder material, and adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 1.5 hours at the rotating speed of 2250r/min at normal temperature to obtain the high-flexibility polymer cement-based waterproof coating.

The preparation method of the modified polycarboxylic acid water reducing agent comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 1 part, lactic acid: 4 parts, sulfamic acid: 5 parts, deionized water: 8 parts of the raw materials are stirred, dissolved and uniformly mixed to obtain a solution A; the polymerization chain transfer agent is mercaptoethanol 8;

preparing solution B: respectively adding potassium permanganate: 1 part, unsaturated polyether: 5 parts, deionized water: 80 parts of the raw materials are stirred and mixed uniformly to obtain a solution B; the unsaturated polyether is nonylphenyl polyoxyethylene ether (NP).

And adding the solution B into a reactor, heating to 70 ℃, dropwise adding the solution A under the stirring condition of 200r/min at the dropping speed of 20 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 3 hours after the dropwise adding is finished, cooling to room temperature after the reaction is finished, and adjusting the pH value to 8.2 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

Example 3

Respectively weighing 40 parts of styrene, 20 parts of methyl methacrylate, 24 parts of n-butyl acrylate, 16 parts of acrylic acid, 40 parts of bisphenol A epoxy resin, 4 parts of hydroquinone, 0.8 part of sodium dodecyl sulfate, 0.8 part of octyl phenol polyoxyethylene ether, 0.4 part of ammonium persulfate, 8 parts of sodium bicarbonate and 240 parts of deionized water according to parts by weight, adding the styrene, the methyl methacrylate, the n-butyl acrylate and the acrylic acid into the bisphenol A epoxy resin, stirring for 15min at the normal temperature at the rotating speed of 180r/min to obtain a mixed monomer, adding the sodium dodecyl sulfate and the octyl phenol polyoxyethylene ether into 1/3 mass of deionized water, stirring for 30min at the rotating speed of 200r/min under the water bath condition of 50 ℃, preserving heat to obtain an emulsifier solution, adding the mixed monomer into the emulsifier solution, stirring for 2h at the rotating speed of 240r/min under the water bath condition of 50 ℃, adding sodium bicarbonate into deionized water of 1/3 mass, stirring for 20min at the rotating speed of 160r/min at normal temperature to obtain sodium bicarbonate solution, adding the sodium bicarbonate solution and hydroquinone into the pre-emulsion, stirring for 2h at the rotating speed of 280r/min under the water bath condition of 40 ℃ to obtain mixed emulsion, adding ammonium persulfate into the rest 1/3 mass of deionized water, stirring for 16min at the rotating speed of 200r/min at normal temperature to obtain ammonium persulfate solution, slowly adding the ammonium persulfate solution into the mixed emulsion at the dropping speed of 30mL/min, stirring and reacting for 2h at the rotating speed of 260r/min under the water bath condition of 90 ℃, cooling to 60 ℃, dropping ammonia water of which the mass fraction is 1% to adjust the pH value to 8, and cooling at normal temperature to obtain epoxy modified styrene-acrylic emulsion;

respectively weighing 40 parts of maltodextrin, 10 parts of polyvinylpyrrolidone, 16 parts of methacryloxy trimethoxy silane and 120 parts of deionized water according to parts by weight, adding the maltodextrin and the polyvinylpyrrolidone into the deionized water, placing the mixture into an ultrasonic dispersion machine, ultrasonically dissolving the mixture for 30min at the temperature of 40 ℃ with the power of 300-400W to obtain a composite wall material solution, adding methacryloxy trimethoxy silane into the composite wall material solution, placing in a high-speed stirrer, stirring at 4500r/min for 10min at normal temperature to obtain emulsion, placing the emulsion in a spray drier, introducing nitrogen for protection, atomizing and drying at the rotating speed of 24000r/min under the conditions of the inlet temperature of 180 ℃ and the outlet temperature of 100 ℃ to obtain solid powder, and cooling the solid powder for 12 hours at room temperature to obtain methacryloxy trimethoxy silane microcapsules;

respectively weighing 120 parts of epoxy modified styrene-acrylic emulsion, 60 parts of portland cement, 12 parts of methacryloxy trimethoxy silane microcapsule, 24 parts of kaolin powder, 24 parts of mica powder, 12 parts of quartz sand, 0.6 part of modified polycarboxylic acid water reducing agent, 0.6 part of sodium stearate, 0.3 part of polydimethylsiloxane, 0.3 part of dodecanol ester and 48 parts of deionized water, adding deionized water, sodium stearate, polydimethylsiloxane and dodecanol ester into the epoxy modified styrene-acrylic emulsion, placing the epoxy modified styrene-acrylic emulsion in a high-speed stirrer, stirring the epoxy modified styrene-acrylic emulsion for 30min at normal temperature at the rotating speed of 1600r/min to obtain a mixed liquid material, placing the portland cement, methacryloxy trimethoxy silane microcapsule, the kaolin powder, the mica powder, the quartz sand and the modified polycarboxylic acid water reducing agent in a stirrer, stirring the mixed liquid material for 40min at normal temperature at the rotating speed of 500r/min to obtain mixed powder material, and adding the mixed powder into the mixed liquid material, placing the mixed liquid material in a high-speed stirrer, and stirring the mixed liquid material for 2 hours at the normal temperature at the rotating speed of 2500r/min to obtain the high-flexibility polymer cement-based waterproof coating.

Comparative example: a polymer cement waterproof coating produced by a company of Henan.

The preparation method of the modified polycarboxylic acid water reducing agent comprises the following steps:

preparation of solution A: respectively adding a polymerization chain transfer agent: 2 parts, lactic acid: 5 parts, sulfamic acid: 8 parts, deionized water: 10 parts of the raw materials are stirred, dissolved and uniformly mixed to obtain solution A; the polymerization chain transfer agent is dodecyl mercaptan;

preparing solution B: respectively adding potassium permanganate: 2 parts of unsaturated polyether: 6 parts of deionized water: 10 parts of the raw materials are stirred and mixed uniformly to obtain a solution B; the unsaturated polyether is methyl enol polyoxyethylene ether (TPEG).

And adding the solution B into a reactor, heating to 75 ℃, dropwise adding the solution A under the stirring condition of 300r/min at the dropping speed of 24 drops/min, wherein the volume ratio of the solution A to the solution B is 8:25, reacting at constant temperature for 5 hours after the dropwise adding is finished, cooling to room temperature after the reaction is finished, and adjusting the pH value to 8.6 by using liquid alkali to obtain the modified polycarboxylic acid water reducer.

The waterproof coating prepared in the embodiment and a reference example are detected, and the specific detection is as follows:

the paint is cut into dumbbell test pieces according to the regulations in GB/T16777-.

Table 1 comparative table of property characterization

Detecting items	Example 1	Example 2	Example 3	Comparative example
					Tensile strength/MPa	2.04	2.34	2.26	1.68
Elongation at break/%	261.3	262.4	263.2	143.5

As can be seen from Table 1, the high-flexibility polymer cement-based waterproof coating prepared by the invention has good tensile strength and elongation at break.