An environmentally friendly polymer cement waterproof coating and its preparation method

Abstract

The present invention relates to the technical field of waterproof coatings, and discloses an environment-friendly polymer cement waterproof coating and a preparation method thereof. The environment-friendly polymer cement waterproof coating is composed of a liquid material and a powder material with a mass ratio of 1:0.8 - 1.1. The liquid material includes the following raw materials: acrylic emulsion, film-forming auxiliary agent, defoaming agent, inorganic modifier, functional composite, and water; the powder material includes the following raw materials: cement, quartz sand, heavy calcium carbonate, sodium stearate, wollastonite, and water reducing agent. By adding an inorganic modifier, the prepared waterproof coating has excellent waterproof performance, the diffusion path of water molecules is extended, and the penetration of water molecules is effectively delayed; by adding a functional composite, the prepared waterproof coating has excellent bonding strength and anti-ultraviolet performance, can be closely combined with the adhered substrate, and still can maintain stable performance under long-term ultraviolet irradiation, having a long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of waterproof coatings, and specifically relates to an environmentally friendly polymer cement waterproof coating and a preparation method thereof. Background Art

[0002] With the development of society and the progress of technology, the gradual increase in engineering construction has put forward higher requirements for the waterproof coatings of buildings. Polymer cement waterproof coatings are environmentally friendly building materials with waterproof functions. They are mainly composed of a liquid material composed of a polymer emulsion and various additives and a powder material composed of cement and various additives. Generally, they are applied to the surface of the building base layer to form a waterproof coating with the rigidity of inorganic powder and the flexibility of polymer organic liquid material. It has the advantages of fast drying speed, excellent physical properties, and good environmental protection. The coating is used to prevent the infiltration of water from small gaps to meet the waterproof requirements.

[0003] The polymer emulsion used in the liquid material of polymer cement waterproof coatings generally uses acrylic emulsion, ethylene-vinyl acetate copolymer emulsion, acrylate emulsion, etc. as the main raw materials. Acrylic emulsion has excellent processing performance, rheology, and thermal stability. It is an excellent polymer emulsion and can be used to prepare polymer cement waterproof coatings. However, the anti-ultraviolet performance of acrylic emulsion is poor. After the waterproof coating prepared from it is irradiated by ultraviolet light during use, the polymer chain will break, resulting in the aging and degradation of the coating, cracking, damage, and even peeling. Moreover, long-term erosion by water vapor or rain will also cause the coating to break and peel, greatly shortening the service life of the waterproof coating. The patent with the publication number CN116004073B discloses a polymer cement waterproof coating, which includes a liquid material modified acrylic ester emulsion and a powder material silicate cement, filler, tannic acid. By mixing the liquid material and the powder material, a waterproof film layer with high crosslinking degree and density can be obtained, improving the water resistance of the polymer cement waterproof coating. However, this patent does not consider the poor anti-ultraviolet performance of polymer cement waterproof coatings, which are easily affected by ultraviolet light and cause the coating to crack and peel. Therefore, the present invention provides an environmentally friendly polymer cement waterproof coating with excellent waterproof performance and anti-ultraviolet performance, long service life, and broad application prospects. Summary of the Invention

[0004] In order to solve the problems mentioned in the background art, the purpose of the present invention is to provide an environmentally friendly polymer cement waterproof coating and a preparation method thereof.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] An environment-friendly polymer cement waterproof coating is composed of a liquid material and a powder material with a mass ratio of 1:0.8 - 1.1. The liquid material comprises the following raw materials in parts by weight: 80 - 100 parts of acrylic emulsion, 3 - 6 parts of film-forming aid, 1 - 4 parts of defoamer, 3 - 6 parts of inorganic modifier, 5 - 8 parts of functional composite, and 14 - 24 parts of water; the powder material comprises the following raw materials in parts by weight: 10 - 35 parts of cement, 10 - 30 parts of quartz sand, 25 - 55 parts of heavy calcium carbonate, 2 - 6 parts of sodium stearate, 10 - 15 parts of wollastonite, and 1 - 4 parts of water reducing agent.

[0007] Further, the film-forming aid is dodecyl acetate; the defoamer is polydimethylsiloxane; the cement is 32.5 white Portland cement or 32.5 gray Portland cement; the particle size of the quartz sand is 120 - 200 mesh; the particle size of the heavy calcium carbonate is 200 - 400 mesh; the water reducing agent is naphthalene-based water reducing agent or polycarboxylate water reducing agent.

[0008] Further, the preparation method of the inorganic modifier comprises the following steps:

[0009] Step A: Add sepiolite into dimethyl sulfoxide, disperse evenly, then raise the temperature to 90 - 100 °C, add 2,2-bis(4-carboxyphenyl)hexafluoropropane and a catalyst, mix evenly, react for 3 - 5 h, then filter, wash, and dry to obtain modified sepiolite;

[0010] Step B: Add the modified sepiolite into N,N-dimethylformamide, mix and stir evenly, then add 2-(tert-butyldimethylsilyloxy)ethylamine, dicyclohexylcarbodiimide, and 4-dimethylaminopyridine, react at room temperature for 4 - 6 h, then separate the product, wash, and dry to obtain the inorganic modifier.

[0011] By adopting the above technical solution, sepiolite contains abundant hydroxyl groups on its surface, which can undergo an esterification reaction with the carboxyl groups in the structure of 2,2-bis(4-carboxyphenyl)hexafluoropropane under the action of high temperature and a catalyst, thereby introducing carboxyl groups on the surface of sepiolite to obtain modified sepiolite. Under the action of dicyclohexylcarbodiimide and 4-dimethylaminopyridine, the carboxyl groups on the surface of the modified sepiolite can undergo an amidation reaction with the amino groups in the structure of 2-(tert-butyldimethylsilyloxy)ethylamine to obtain the inorganic modifier.

[0012] Further, in step A, the catalyst is p-toluenesulfonic acid.

[0013] Further, the preparation method of the functional composite comprises the following steps:

[0014] Step S1: Add polytetrahydrofuran ether diol into tetrahydrofuran. After mixing evenly, introduce nitrogen for protection, add a haloacyl chloride modifier and a promoter, stir and react for 3 - 5 h. After removing the solvent by vacuum distillation, discharge the material to obtain an intermediate substance;

[0015] Step S2: Add the intermediate substance into dimethyl sulfoxide, stir and mix evenly, introduce nitrogen for protection, raise the temperature to 70 - 80 °C, add 2,2,6,6 - tetramethylpiperidinol and potassium carbonate, react for 4 - 5 h, then cool to room temperature and discharge the material to obtain a functional composite.

[0016] By adopting the above technical solution, the hydroxyl group in the structure of polytetrahydrofuran ether diol can react with the acyl chloride in the structure of the haloacyl chloride modifier under the action of the promoter, thereby obtaining an intermediate substance with a halogen substituent. Under the action of potassium carbonate, the halogen substituent in the structure of the intermediate substance can undergo a substitution reaction with the hydroxyl group in the structure of 2,2,6,6 - tetramethylpiperidinol to obtain a functional composite.

[0017] Further, in step S1, the haloacyl chloride modifier is any one of chloroacetyl chloride, bromoacetyl chloride or 3 - chloropropionyl chloride.

[0018] Further, in step S1, the promoter is triethylamine or pyridine.

[0019] A preparation method of an environmentally friendly polymer cement waterproof coating includes the following steps:

[0020] Step 1: Add acrylic emulsion into water. After mixing evenly, add a film - forming aid, an antifoaming agent, an inorganic modifier, and the functional composite, then start stirring, set the stirring rate to 100 - 300 r / min, and stir for 15 - 45 min to obtain a liquid material;

[0021] Step 2: Mix cement, quartz sand, heavy calcium carbonate, sodium stearate, wollastonite, and a water - reducing agent evenly, start stirring, set the stirring rate to 200 - 400 r / min, and stir for 10 - 40 min to obtain a powder material;

[0022] Step 3: Add the liquid material and the powder material with a mass ratio of 1:0.8 - 1.1 into a high - speed mixer, set the stirring rate to 150 - 350 r / min, and stir for 10 - 35 min to obtain the environmentally friendly polymer cement waterproof coating.

[0023] The beneficial effects of the present invention:

[0024] (1) The inorganic modified material prepared by the present invention uses sepiolite as the matrix. Through the organic modification of sepiolite, the compatibility between the inorganic modified material and the polymer emulsion is improved, avoiding agglomeration in the polymer emulsion, promoting the uniform dispersion of the inorganic modified material in the coating, enhancing the interfacial bonding force and intermolecular cohesion between sepiolite and the polymer emulsion, thereby improving the density of the coating. At the same time, sepiolite has a layered structure and is uniformly dispersed in the coating, forming a multi-layer barrier structure, which can extend the diffusion path of water molecules and effectively delay the penetration of water molecules. In addition, introducing rigid benzene rings, fluorine-containing segments and tert-butyl groups with hydrophobic effects on the surface of sepiolite can effectively reduce the surface energy of sepiolite, further preventing the penetration of water molecules and greatly improving the waterproof performance of the coating.

[0025] (2) The functional composite prepared by the present invention can crosslink with the polymer emulsion to form a polymer network structure, making the cohesive force stronger. On the one hand, the ether bonds in the structure of the functional composite can improve the flexibility of the coating, enabling the waterproof coating to better adapt to minor deformations. On the other hand, it can promote the combination between the polymer and the powder, improve the adhesion between the coating and the substrate, and enhance the bonding strength. At the same time, by means of chemical bonding, a hindered amine group with anti-ultraviolet effect is introduced into the structure of the functional composite. By absorbing ultraviolet light, capturing free radicals and reacting with free radicals, it protects the coating from ultraviolet erosion and also avoids the migration and precipitation of small molecule anti-ultraviolet substances, resulting in a decline in anti-ultraviolet performance in the later stage and the occurrence of coating cracking, damage or even peeling under the action of ultraviolet irradiation, thereby extending the service life of the waterproof coating.

[0026] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is the infrared spectrogram of the inorganic modified material in the present invention. Detailed Embodiments

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0030] The preparation methods of the inorganic modifier and the composite additive in the following examples and comparative examples are as follows:

[0031] I. Preparation of the inorganic modifier

[0032] Step A: Add 3.6 g of sepiolite into dimethyl sulfoxide. After dispersing evenly, raise the temperature to 95 °C, add 1.8 g of 2,2-bis(4-carboxyphenyl)hexafluoropropane and 0.5 g of p-toluenesulfonic acid, mix evenly, react for 4 h, then filter, wash, and dry to obtain modified sepiolite;

[0033] Step B: Add 3.4 g of modified sepiolite into N,N-dimethylformamide. After mixing and stirring evenly, add 1.5 g of 2-(tert-butyldimethylsilyloxy)ethylamine, 0.3 g of dicyclohexylcarbodiimide, and 0.1 g of 4-dimethylaminopyridine. React at room temperature for 5 h, then separate the product, wash, and dry to obtain the inorganic modifier.

[0034] The inorganic modifier was subjected to infrared testing using a Fourier transform infrared spectrometer. As Figure 1 shown, it can be analyzed that in the infrared spectrum of the inorganic modifier, an absorption peak of the carbon-hydrogen bond in the benzene ring appears at 3032 cm -1 an absorption peak of the carbon-oxygen double bond in the ester group appears at 1745 cm -1 an absorption peak of the carbon-oxygen double bond in the amide bond appears at 1660 cm -1 an absorption peak of the tert-butyl group appears at 1367 cm -1 an absorption peak of the carbon-fluorine bond appears at 1246 cm -1 an absorption peak of the silicon-oxygen bond appears at 1035 cm -1

[0035] II. Preparation of the composite additive

[0036] Step S1: Add 4 g of polytetrahydrofuran ether diol into tetrahydrofuran. After mixing evenly, introduce nitrogen protection, add 2.9 g of chloroacetyl chloride and 0.8 g of triethylamine, stir and react for 5 h. After removing the solvent by vacuum distillation, discharge to obtain the intermediate substance;

[0037] Step S2: Add 3.5 g of the intermediate substance into dimethyl sulfoxide, stir and mix evenly, introduce nitrogen protection, raise the temperature to 75 °C, add 1.6 g of 2,2,6,6-tetramethylpiperidinol and 0.5 g of potassium carbonate, react for 5 h, then cool to room temperature and discharge to obtain the functional composite.

[0038] ​The organic element content of the functional complex was analyzed using a Vario EL Ⅲ elemental analyzer. From the test results, it can be seen that the percentage content of nitrogen element in the functional complex is 4.53%. Since polytetrahydrofuran ether diol does not contain nitrogen element, it can be reasonably speculated that the reaction between 2,2,6,6-tetramethylpiperidinol and polytetrahydrofuran ether diol was successful, providing a nitrogen source.

[0039] Example 1

[0040] Preparation of environment-friendly polymer cement waterproof coating

[0041] Step 1: Add 80 g of acrylic emulsion to 14 g of water. After mixing evenly, add 3 g of lauryl alcohol ester film-forming aid, 1 g of polydimethylsiloxane defoamer, 3 g of inorganic modifier, and 5 g of functional complex, and start stirring. Set the stirring rate to 100 r / min. After stirring for 15 min, a liquid material is obtained.

[0042] Step 2: Mix 10 g of 32.5-grade gray Portland cement, 10 g of quartz sand with a particle size of 120 mesh, 25 g of heavy calcium carbonate with a particle size of 200 mesh, 2 g of sodium stearate, 10 g of wollastonite, and 1 g of polycarboxylate water reducer evenly, start stirring, set the stirring rate to 200 r / min, and after stirring for 10 min, a powder material is obtained.

[0043] Step 3: Add the liquid material and the powder material with a mass ratio of 1:0.8 to a high-speed mixer, set the stirring rate to 150 r / min, and stir for 10 min to obtain the environment-friendly polymer cement waterproof coating.

[0044] Example 2

[0045] Preparation of environment-friendly polymer cement waterproof coating

[0046] Step 1: Add 85 g of acrylic emulsion to 16 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, 4 g of inorganic modifier, and 6 g of functional complex, and start stirring. Set the stirring rate to 150 r / min. After stirring for 25 min, a liquid material is obtained.

[0047] Step 2: Mix 20 g of 32.5-grade gray Portland cement, 14 g of quartz sand with a particle size of 160 mesh, 35 g of heavy calcium carbonate with a particle size of 300 mesh, 4 g of sodium stearate, 12 g of wollastonite, and 2 g of polycarboxylate water reducer evenly, start stirring, set the stirring rate to 250 r / min, and after stirring for 20 min, a powder material is obtained.

[0048] Step 3: Add the liquid material and powder material with a mass ratio of 1:0.9 into a high-speed mixer, set the stirring rate to 200 r / min, and stir for 20 min to obtain the environmentally friendly polymer cement waterproof coating.

[0049] Example 3

[0050] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0051] Step 1: Add 90 g of acrylic emulsion into 18 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, 5 g of inorganic modifier, and 7 g of functional composite, then start stirring. Set the stirring rate to 200 r / min and stir for 35 min to obtain the liquid material;

[0052] Step 2: Mix 30 g of 32.5-grade gray portland cement, 20 g of quartz sand with a particle size of 180 mesh, 45 g of heavy calcium carbonate with a particle size of 350 mesh, 5 g of sodium stearate, 14 g of wollastonite, and 3 g of polycarboxylate water reducer evenly, then start stirring. Set the stirring rate to 300 r / min and stir for 30 min to obtain the powder material;

[0053] Step 3: Add the liquid material and powder material with a mass ratio of 1:1 into a high-speed mixer, set the stirring rate to 250 r / min, and stir for 30 min to obtain the environmentally friendly polymer cement waterproof coating.

[0054] Example 4

[0055] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0056] Step 1: Add 100 g of acrylic emulsion into 24 g of water. After mixing evenly, add 6 g of lauryl alcohol ester film-forming aid, 4 g of polydimethylsiloxane defoamer, 6 g of inorganic modifier, and 8 g of functional composite, then start stirring. Set the stirring rate to 300 r / min and stir for 45 min to obtain the liquid material;

[0057] Step 2: Mix 35 g of 32.5-grade gray portland cement, 30 g of quartz sand with a particle size of 200 mesh, 55 g of heavy calcium carbonate with a particle size of 400 mesh, 6 g of sodium stearate, 15 g of wollastonite, and 4 g of polycarboxylate water reducer evenly, then start stirring. Set the stirring rate to 400 r / min and stir for 40 min to obtain the powder material;

[0058] Step 3: Add the liquid material and powder material with a mass ratio of 1:1.1 into a high-speed mixer, set the stirring rate to 350 r / min, and stir for 35 min to obtain the environmentally friendly polymer cement waterproof coating.

[0059] Comparative Example 1

[0060] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0061] Step 1: Add 90 g of acrylic emulsion to 18 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, and 5 g of inorganic modifier, and start stirring. Set the stirring rate to 200 r / min. After stirring for 35 min, a liquid material is obtained.

[0062] Step 2: Mix 30 g of 32.5-grade gray Portland cement, 20 g of quartz sand with a particle size of 180 mesh, 45 g of heavy calcium carbonate with a particle size of 350 mesh, 5 g of sodium stearate, 14 g of wollastonite, and 3 g of polycarboxylate water reducer evenly, start stirring. Set the stirring rate to 300 r / min. After stirring for 30 min, a powder material is obtained.

[0063] Step 3: Add the liquid material and the powder material with a mass ratio of 1:1 to a high-speed mixer. Set the stirring rate to 250 r / min and stir for 30 min to obtain the environmentally friendly polymer cement waterproof coating.

[0064] Comparative Example 2

[0065] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0066] Step 1: Add 90 g of acrylic emulsion to 18 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, and 7 g of functional complex, and start stirring. Set the stirring rate to 200 r / min. After stirring for 35 min, a liquid material is obtained.

[0067] Step 2: Mix 30 g of 32.5-grade gray Portland cement, 20 g of quartz sand with a particle size of 180 mesh, 45 g of heavy calcium carbonate with a particle size of 350 mesh, 5 g of sodium stearate, 14 g of wollastonite, and 3 g of polycarboxylate water reducer evenly, start stirring. Set the stirring rate to 300 r / min. After stirring for 30 min, a powder material is obtained.

[0068] Step 3: Add the liquid material and the powder material with a mass ratio of 1:1 to a high-speed mixer. Set the stirring rate to 250 r / min and stir for 30 min to obtain the environmentally friendly polymer cement waterproof coating.

[0069] Comparative Example 3

[0070] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0071] Step 1: Add 90 g of acrylic emulsion to 18 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, 5 g of sepiolite, and 7 g of functional composite, then start stirring. Set the stirring rate to 200 r / min. After stirring for 35 min, a liquid material is obtained;

[0072] Step 2: Mix 30 g of 32.5-grade gray portland cement, 20 g of quartz sand with a particle size of 180 mesh, 45 g of heavy calcium carbonate with a particle size of 350 mesh, 5 g of sodium stearate, 14 g of wollastonite, and 3 g of polycarboxylate water reducer evenly, then start stirring. Set the stirring rate to 300 r / min. After stirring for 30 min, a powder material is obtained;

[0073] Step 3: Add the liquid material and the powder material with a mass ratio of 1:1 to a high-speed mixer. Set the stirring rate to 250 r / min and stir for 30 min to obtain an environmentally friendly polymer cement waterproof coating.

[0074] Comparative Example 4

[0075] Preparation of Environmentally Friendly Polymer Cement Waterproof Coating

[0076] Step 1: Add 90 g of acrylic emulsion to 18 g of water. After mixing evenly, add 4 g of lauryl alcohol ester film-forming aid, 2 g of polydimethylsiloxane defoamer, 5 g of inorganic modifier, and 7 g of 2,2,6,6-tetramethylpiperidinol, then start stirring. Set the stirring rate to 200 r / min. After stirring for 35 min, a liquid material is obtained;

[0077] Step 2: Mix 30 g of 32.5-grade gray portland cement, 20 g of quartz sand with a particle size of 180 mesh, 45 g of heavy calcium carbonate with a particle size of 350 mesh, 5 g of sodium stearate, 14 g of wollastonite, and 3 g of polycarboxylate water reducer evenly, then start stirring. Set the stirring rate to 300 r / min. After stirring for 30 min, a powder material is obtained;

[0078] Step 3: Add the liquid material and the powder material with a mass ratio of 1:1 to a high-speed mixer. Set the stirring rate to 250 r / min and stir for 30 min to obtain an environmentally friendly polymer cement waterproof coating.

[0079] Performance Testing

[0080] Refer to the standard GB / T 23445-2009 "Polymer Cement Waterproof Coating" to test the environmentally friendly polymer cement waterproof coatings prepared in Examples 1 - 4 and Comparative Examples 1 - 4 for water impermeability, impermeability, and bond strength. After the waterproof coating is placed for 6 months and then cured to form a coating, test the appearance change of the coating after 7 days of ultraviolet treatment. The test results are shown in the following table:

[0081]

[0082] As can be seen from the above table, the environment-friendly polymer cement waterproof coating prepared by the present invention has excellent waterproof performance, bonding strength and anti-ultraviolet performance. In Comparative Example 1, inorganic modifiers were added but functional composites were not added. The waterproof coating has excellent waterproof performance but poor bonding strength and anti-ultraviolet performance. In Comparative Example 2, functional composites were added but inorganic modifiers were not added. The bonding strength and anti-ultraviolet performance are excellent but the waterproof performance is poor. In Comparative Example 3, sepiolite and functional composites were added. Sepiolite is prone to agglomeration and was not modified with hydrophobic benzene rings, fluorine-containing segments and tert-butyl groups. The waterproof performance is poor, but the bonding strength and anti-ultraviolet performance are excellent. In Comparative Example 4, inorganic modifiers and 2,2,6,6-tetramethylpiperidinol were added. The waterproof performance is excellent, but 2,2,6,6-tetramethylpiperidinol is prone to migration and precipitation, resulting in a decrease in anti-ultraviolet performance. Therefore, the bonding strength and anti-ultraviolet performance are poor.

[0083] The above content is only an example and illustration of the concept of the present invention. Those skilled in the art of the present technology can make various modifications or supplements to the specific embodiments described or use similar methods to replace them. As long as they do not deviate from the concept of the invention or exceed the scope defined by this claim book, they should fall within the protection scope of the present invention.

Claims

1. An environmentally friendly polymer cement waterproof coating, characterized in that, It is composed of a liquid material and a powder material with a mass ratio of 1:0.8 - 1.

1. The liquid material includes the following raw materials in parts by weight: 80 - 100 parts of acrylic emulsion, 3 - 6 parts of film-forming auxiliary, 1 - 4 parts of defoamer, 3 - 6 parts of inorganic modifier, 5 - 8 parts of functional composite, and 14 - 24 parts of water; the powder material includes the following raw materials in parts by weight: 10 - 35 parts of cement, 10 - 30 parts of quartz sand, 25 - 55 parts of heavy calcium carbonate, 2 - 6 parts of sodium stearate, 10 - 15 parts of wollastonite, and 1 - 4 parts of water reducer. The inorganic modifier is prepared by the following method: Step A: Add sepiolite into dimethyl sulfoxide, disperse evenly, then raise the temperature to 90 - 100 °C, add 2,2-bis(4-carboxyphenyl)hexafluoropropane and a catalyst, mix evenly, react for 3 - 5 h, then filter, wash, and dry to obtain modified sepiolite. Step B: Add the modified sepiolite into N,N-dimethylformamide, mix and stir evenly, then add 2-(tert-butyldimethylsilyloxy)ethylamine, dicyclohexylcarbodiimide, and 4-dimethylaminopyridine, react at room temperature for 4 - 6 h, then separate the product, wash, and dry to obtain the inorganic modifier. The functional composite is prepared by the following method: Step S1: Add polytetrahydrofuran ether glycol into tetrahydrofuran, mix evenly, then introduce nitrogen protection, add a haloacyl chloride modifier and a promoter, stir and react for 3 - 5 h, distill off the solvent under reduced pressure, and then discharge to obtain an intermediate substance. Step S2: Add the intermediate substance into dimethyl sulfoxide, stir and mix evenly, introduce nitrogen protection, raise the temperature to 70 - 80 °C, add 2,2,6,6-tetramethylpiperidinol and potassium carbonate, react for 4 - 5 h, then cool to room temperature and discharge to obtain the functional composite.

2. The environmentally friendly polymer cement waterproof coating according to claim 1, characterized in that The film-forming auxiliary is lauryl alcohol ester; the defoamer is polydimethylsiloxane; the cement is 32.5 white Portland cement or 32.5 gray Portland cement; the particle size of the quartz sand is 120 - 200 mesh; the particle size of the heavy calcium carbonate is 200 - 400 mesh; the water reducer is naphthalene-based water reducer or polycarboxylate water reducer.

3. An environment-friendly polymer cement waterproof coating according to claim 1, characterized in that, In step A, the catalyst is p-toluenesulfonic acid.

4. An environment-friendly polymer cement waterproof coating according to claim 1, characterized in that, In step S1, the haloacyl chloride modifier is any one of chloroacetyl chloride, bromoacetyl chloride, or 3-chloropropionyl chloride.

5. An environmentally friendly polymer cement waterproof coating according to claim 1, characterized in that, In step S1, the promoter is triethylamine or pyridine.

6. A preparation method of the environment-friendly polymer cement waterproof coating as described in claim 1, characterized in that, It includes the following steps: Step one: Add the acrylic emulsion into water, mix evenly, then add the film-forming auxiliary, defoamer, inorganic modifier, and functional composite, start stirring, set the stirring rate to 100 - 300 r / min, and stir for 15 - 45 min to obtain the liquid material. Step two: Mix the cement, quartz sand, heavy calcium carbonate, sodium stearate, wollastonite, and water reducer evenly, start stirring, set the stirring rate to 200 - 400 r / min, and stir for 10 - 40 min to obtain the powder material. Step 3: Add liquid material and powder material with a mass ratio of 1:0.8 - 1.1 into a high-speed mixer, set the stirring rate to 150 - 350 r / min, and stir for 10 - 35 min to obtain the environment-friendly polymer cement waterproof coating.

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