阅读说明：本技术 一种高耐水聚合物水泥防水涂料及其制备工艺 (High-water-resistance polymer cement waterproof coating and preparation process thereof ) 是由 张冬冬 刘新永 常志 李超 王威 鞠立波 刘兴邦 桑喆 于 2021-11-05 设计创作，主要内容包括：本发明提供一种高耐水聚合物水泥防水涂料,其特征在于：所述的涂料包括液料和粉料；所述液料包括纳米二氧化硅溶液、钛酸酯偶联剂、丁苯乳液、分散剂、消泡剂以及防腐剂。所述粉料,以质量份计,包括以下组分：水泥35～70份、沸石粉10～20份、填料10～55份、减水剂0.1～0.5份。本发明制备的聚合物水泥防水涂料涂膜的吸水率低、耐水性能高、与后续施工材料粘接性能优异,且不会释放VOC；可很好的适用于长期浸水的环境,如地下建筑、消防水池、游泳池等工程的防水保护。(The invention provides a high-water-resistance polymer cement waterproof coating which is characterized in that: the coating comprises a liquid material and a powder material; the liquid material comprises a nano silicon dioxide solution, a titanate coupling agent, a butylbenzene emulsion, a dispersing agent, a defoaming agent and a preservative. The powder comprises the following components in parts by mass: 35-70 parts of cement, 10-20 parts of zeolite powder, 10-55 parts of filler and 0.1-0.5 part of water reducing agent. The polymer cement waterproof coating film prepared by the invention has low water absorption, high water resistance, excellent adhesion performance with subsequent construction materials and no VOC release; the waterproof paint can be well suitable for the long-term water immersion environment, such as waterproof protection of projects of underground buildings, fire-fighting water pools, swimming pools and the like.)

1. A high-water-resistance polymer cement waterproof coating is characterized in that: the coating comprises a liquid material and a powder material; the liquid material comprises a nano silicon dioxide solution, a titanate coupling agent, a butylbenzene emulsion, a dispersing agent, a defoaming agent and a preservative.

2. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: the nano silicon dioxide solution comprises the following raw material components in parts by weight: 8-10 parts of concentrated ammonia water, 4-5 parts of ethyl orthosilicate, 24-26 parts of pure water and 59-63 parts of absolute ethyl alcohol.

3. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: the liquid material comprises the following components in parts by mass: 5-15 parts of nano silicon dioxide solution, 0.05-0.15 part of titanate coupling agent, 85-95 parts of butylbenzene emulsion, 0.1-0.3 part of dispersing agent, 0.3-0.6 part of defoaming agent and 0.05-0.1 part of preservative.

4. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: the powder comprises the following components in parts by mass: 35-70 parts of cement, 10-20 parts of zeolite powder, 10-55 parts of filler and 0.1-0.5 part of water reducing agent.

5. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: when in use, the liquid material and the powder material are mixed according to the ratio of 1: (1-2) preparing the mixture according to the mass ratio.

6. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: the titanate coupling agent is one or the combination of more of monoalkoxy type, monoalkoxy pyrophosphate type, integration type and ligand type titanate coupling agent; the dispersant refers to one or more of polyacrylate, polycarboxylate, naphthalenesulfonate polycondensate and polyisobutylene maleic acid salt; the defoaming agent is one or a combination of more of mineral oil, organic silicon and polyether.

7. The high water-resistant polymer cement waterproof coating material as claimed in claim 1, wherein: the preservative is one or a combination of more of isothiazolinone, benzimidazole, substituted aromatic hydrocarbon, organic bromine, organic amine and piperatriazine; the filler is one or a combination of more of quartz powder, calcium carbonate, calcium phosphate, mica powder, barium sulfate, kaolin, quartz sand and river sand.

8. A preparation process of a high-water-resistance polymer cement waterproof coating is characterized by comprising the following steps of: comprises the steps of preparing a nano silicon dioxide solution; preparing a nano silicon dioxide solution: preparing a solution a: respectively weighing ethyl orthosilicate and part of absolute ethyl alcohol in a container, and uniformly mixing to prepare an ethyl orthosilicate ethanol solution with the mass fraction of 9-11%;

preparing solution b, namely respectively weighing concentrated ammonia water, pure water and the residual absolute ethyl alcohol into a container, and starting stirring, wherein the stirring speed is 900rpm-1100 rpm;

quickly adding the solution a into the solution b, after 4-6min, reducing the stirring speed to 400-600 rpm, and keeping the rotating speed for reacting for 1-1.5h to obtain a solution c;

and distilling the obtained solution c at the rotating speed of 300-400 rpm to obtain a solution d, namely a nano silicon dioxide solution.

9. The preparation process of the high water-resistant polymer cement waterproof coating material according to claim 8, characterized in that: the nano silicon dioxide solution: the mass percentage of the nano silicon dioxide is 10-13%.

10. The preparation process of the high water-resistant polymer cement waterproof coating material according to claim 8, characterized in that: the preparation process of the liquid material comprises the following steps: stirring the nano silicon dioxide solution at the speed of 700-900rpm, uniformly adding the titanate coupling agent within 2-3 minutes, reducing the rotation speed to 650rpm after stirring for 8-12 minutes, sequentially adding the butylbenzene emulsion, the defoaming agent and the preservative, and stirring until the mixture is uniformly mixed.

Technical Field

The invention provides a high-water-resistance polymer cement waterproof coating and a preparation process thereof, which are a building waterproof coating and a preparation process thereof, and belong to the field of waterproof coatings.

Background

The polymer cement waterproof coating (JS waterproof coating) is a two-component water-based building waterproof coating which is prepared by reasonably proportioning and compounding organic liquid materials consisting of polymer emulsions such as polyacrylate emulsion, ethylene-vinyl acetate copolymer emulsion and the like and various additives and inorganic powder materials consisting of inorganic fillers such as cement, quartz sand, light and heavy calcium carbonate and the like and various additives.

The JS waterproof coating has many advantages, such as water-based no pollution, good adhesion with a wet base layer, rigidity, flexibility, high cost performance and the like. The series of advantages make it become a popular waterproof coating, widely used in kitchen, toilet, balcony, floor, outer wall and other industrial and civil engineering for water and moisture proofing; is particularly suitable for waterproofing complex parts such as curves, special-shaped structures and the like.

At present, most of polymer cement waterproof coatings sold on the market only meet the requirements of GB/T23445-2009 standard, but the traditional polymer cement waterproof coatings cannot be applied to waterproof engineering of long-term water immersion due to the problem of limited water resistance. After the polymer cement waterproof coating prepared from the polyacrylate emulsion and the ethylene-vinyl acetate copolymer emulsion is soaked in water for a long time, particularly in an alkaline building environment, the water absorption swelling and hydrolysis can be realized to different degrees, and the water absorption can be realized to different degrees, so that the impermeability, the tensile property and the acid and alkali resistance of a coating film of the polymer cement waterproof coating are attenuated to different degrees, a waterproof system fails, and extremely serious damage is brought to a building.

The traditional polymer cement waterproof coating is a continuous structure network which takes a polymer network structure as a main body and is embedded with cement, other inorganic fillers and hydration products, and simultaneously, the interface combination is realized because chemical bonding exists between the polymer and the cement. The reason why the coating film of the conventional polymer cement waterproof coating is not water-resistant is that the hydrolysis problem of the polymer itself, the water absorption problem of the powder and the interface bonding between the polymer and the powder are not tight enough. After the conventional polymer cement waterproof coating is formed into a film, cement hydration is not complete, so that the interface combination of powder particles and a polymer structure is very limited, and the interface is easy to be invaded by water, so that the water resistance of the coating film is poor. The traditional polymer cement waterproof coating has hydrolysis phenomena of different degrees after a coating film is soaked in water, so that the coating film is expanded, the water absorption rate is very high, and the loss of physical properties such as tensile strength, elongation at break, bonding strength, impermeability and the like is serious; on the other hand, the acrylic emulsion can be slowly hydrolyzed under the alkaline condition after being mixed with cement, and VOC is volatile organic matter and causes certain damage to the environment and human bodies.

Meanwhile, in order to enhance the water-resistant effect, more hydrophobing agents, water repellents and the like are often added in the traditional water-resistant coating, so that partial adhesive property of a coating film and a subsequent construction material is sacrificed to a certain extent.

Through search, the polymer waterproof coating in the prior art is found to be incapable of solving the technical problems. The CN200910027627.5 nano-material modified I-type polymer cement waterproof coating and the preparation method thereof comprise a liquid material component and a powder material component, wherein the liquid material component comprises the following components in parts by weight: 50-70% of ethylene-vinyl acetate emulsion; 20-40% of acrylate emulsion and 5-7% of plasticizer; 0.1-0.3% of a dispersant; 0.1-0.4% of organic silicon defoaming agent; 0.1-0.3% of preservative; the content of active ingredients of the pre-dispersed nano silicon dioxide solution is 0.15-0.45%; the content of active ingredients of the pre-dispersed nano alumina solution is 0.02-0.06%; the balance of water; the mixing ratio of the liquid material component to the powder material component is 10: 7-10 in terms of weight ratio. CN 201510821972.1A polymer cement composite waterproof coating and a preparation method thereof, wherein the modified powder is prepared from the following components in percentage by mass: 5% of nano silicon carbide, 5% of kaolin powder, 5% of nano boron carbide, 5% of fly ash, 0.02% of micro aluminum oxide, 0.01% of graphene, 0.2% of modified starch, 0.3% of potassium carbonate, 0.05% of rare earth light conversion agent and the balance of nano silicon dioxide; the emulsion is prepared from the following components in percentage by mass: 60% of pure acrylic emulsion, 0.5% of defoaming agent, 4% of polyether polyol, 6% of polyurethane thickener, 0.2% of preservative, 1% of hydroxyethyl cellulose, 0.8% of sodium dodecyl sulfate, 3% of propyl benzene emulsion, 0.4% of dispersant and the balance of deionized water.

Although the two technical schemes of the invention improve the weather resistance and the water resistance to a certain extent. But the problems of the environment of long-term soaking, the bonding performance of a coating and a subsequent construction material, the expansion and water absorption of a waterproof coating after coating and the release of VOC are not solved.

In conclusion, the polymer cement waterproof coating film in the prior art has poor subsequent bonding performance with subsequent construction materials, is used in a long-term water immersion environment, has high water absorption rate, and influences the engineering service life; release VOC, and are not beneficial to the environment and human health.

Disclosure of Invention

Aiming at the technical problems, the invention provides a high-water-resistance polymer cement waterproof coating and a preparation process thereof, and aims to achieve the following aims: the prepared polymer cement waterproof coating film has low water absorption rate, high water resistance, excellent adhesion performance with subsequent construction materials and no release of VOC; the waterproof paint can be well suitable for the long-term water immersion environment, such as waterproof protection of projects of underground buildings, fire-fighting water pools, swimming pools and the like.

In order to achieve the purpose of the invention, the following technical scheme is adopted:

the invention provides a high water-resistant polymer cement waterproof coating and a preparation process thereof, wherein the coating comprises a liquid material and a powder material; the liquid material comprises a nano silicon dioxide solution, a titanate coupling agent, a butylbenzene emulsion, a dispersing agent, a defoaming agent and a preservative.

The nano silicon dioxide solution comprises the following raw material components in parts by weight: 8-10 parts of concentrated ammonia water, 4-5 parts of ethyl orthosilicate, 24-26 parts of pure water and 59-63 parts of absolute ethyl alcohol.

The liquid material comprises the following components in parts by mass: 5-15 parts of nano silicon dioxide solution, 0.05-0.15 part of titanate coupling agent, 85-95 parts of butylbenzene emulsion, 0.1-0.3 part of dispersing agent, 0.3-0.6 part of defoaming agent and 0.05-0.1 part of preservative.

The powder comprises the following components in parts by mass: 35-70 parts of cement, 10-20 parts of zeolite powder, 10-55 parts of filler and 0.1-0.5 part of water reducing agent.

A preparation process of a high-water-resistance polymer cement waterproof coating comprises the following steps:

step 1, preparing a nano silicon dioxide solution:

the nano silicon dioxide solution comprises the following raw material components in parts by weight: 8-10 parts of concentrated ammonia water, 4-5 parts of ethyl orthosilicate, 24-26 parts of pure water and 59-63 parts of absolute ethyl alcohol.

Preferably, the nano-silica solution comprises the following raw material components in parts by weight: 9 parts of concentrated ammonia water, 4.5 parts of ethyl orthosilicate, 25 parts of pure water and 61.5 parts of absolute ethyl alcohol.

The preparation process comprises the following steps:

(1) preparing a solution a: respectively weighing ethyl orthosilicate and part of absolute ethyl alcohol in a container, and uniformly mixing to prepare an ethyl orthosilicate ethanol solution with the mass fraction of 10%;

(2) preparing solution b, namely respectively weighing concentrated ammonia water, pure water and the residual absolute ethyl alcohol into a container, and starting stirring, wherein the stirring speed is 900rpm-1100 rpm;

(3) quickly adding the solution a into the solution b, reducing the stirring speed to 400-600 rpm after 5min, and keeping the rotating speed for reacting for 1h to obtain a solution c;

(4) and distilling the obtained solution c at the rotating speed of 300-400 rpm to obtain a solution d, namely a nano silicon dioxide solution. The mass of the solution d obtained after distillation was 10% of the mass of the solution c. In the solution d, the mass percentage of the nano silicon dioxide is 12%.

Step 2, preparing liquid material:

the invention relates to a liquid material of a high-water-resistance polymer cement waterproof coating, which comprises the following components in parts by mass:

the following preparation process is adopted: stirring the nano silicon dioxide solution prepared in the step 1 at the speed of 700-900rpm, uniformly adding the titanate coupling agent within 2-3 minutes, reducing the rotation speed to 550-650rpm after stirring for 8-12 minutes, sequentially adding the butylbenzene emulsion, the defoaming agent and the preservative, and stirring until the mixture is uniformly mixed.

Step 3, preparing powder:

the invention relates to a powder material of a high-water-resistance polymer cement waterproof coating, which comprises the following components in parts by mass:

the preparation process comprises the following steps: mixing the above powder materials uniformly.

When in use, the liquid material and the powder material are mixed according to the ratio of 1: (1-2) preparing the mixture according to the mass ratio.

The concentration of the strong ammonia water is 25 percent;

the purity of the ethyl orthosilicate is more than 96 percent;

the purity of the absolute ethyl alcohol is 99.5 percent;

the titanate coupling agent is one or the combination of more of monoalkoxy type, monoalkoxy pyrophosphate type, integration type and ligand type titanate coupling agents.

The styrene-butadiene emulsion comprises the following components: the glass transition temperature is between-20 ℃ and-5 ℃, and the butadiene-styrene copolymer is prepared by copolymerizing butadiene and styrene emulsion.

The dispersant refers to one or more of polyacrylate, polycarboxylate, naphthalenesulfonate polycondensate and polyisobutylene maleic acid salt.

The defoaming agent is one or a combination of more of mineral oil, organic silicon and polyether.

The preservative is one or a combination of more of isothiazolinone, benzimidazole, substituted aromatic hydrocarbon, organic bromine, organic amine and piperatriazine.

The cement is one or more of Portland cement, high-alumina cement and sulpho-alumina cement.

The zeolite powder is prepared by the following steps: the mesh number is 400-800 meshes.

The filler is one or a combination of more of quartz powder, calcium carbonate, calcium phosphate, mica powder, barium sulfate, kaolin, quartz sand and river sand.

The water reducing agent is preferably a naphthalene water reducing agent, a polycarboxylic acid water reducing agent or a melamine water reducing agent.

The invention adopts the specially-prepared nano silicon dioxide solution, is matched with other specific components and specific processes to prepare the high-water-resistance polymer cement waterproof coating, and achieves the following beneficial effects:

(1) the polymer cement waterproof coating has excellent water resistance. The styrene-butadiene emulsion is used as polymer support and is matched with other components, and the prepared coating has the property of being not easy to hydrolyze in the structure. The retention rate of the water resistance and the physical property of the coating film is improved, and VOC can not be released. According to the liquid material, the nano silicon dioxide and the polymer are combined in advance through the matching of specific components, a tiny gap is generated in the film-forming and water-loss process of the coating, the nano silicon dioxide enters the gap, a macromolecular chain of the polymer can also partially enter the gap, the combination between inorganic matters and organic matters is enhanced while the gap is filled, and the water resistance of a coating film is greatly improved. The powder material is matched with the specific components, and reacts with a hydration product calcium hydroxide of cement to generate a gelled substance in the film forming process, so that chemical bonds are generated between the gelled substance and the polymer, and the interface bonding is strengthened; the cement is completely hydrated, and the bonding effect of the cement and the polymer is good. Meanwhile, the zeolite powder has a porous structure, so that the zeolite powder has strong carrying capacity and improves the combination with surrounding materials.

(2) The polymer cement waterproof coating is prepared under the condition of not adding a hydrophobic agent and a water repellent agent, and has good water resistance and water resistance without hydrophobicity. The conventional waterproof coating generally achieves the aim of waterproofing by adding a hydrophobic agent, a water repellent agent and the like, and partial adhesive property of a coating film and a subsequent construction product is sacrificed to a certain extent. The invention has the advantages of no addition of hydrophobic and hydrophobic components, high water resistance and high subsequent bonding strength. Water-resistant, not hydrophobic, is an advanced technology in the art.

(3) The adhesive strength between the coating film and the base layer of the polymer cement waterproof coating is high, and the adhesive strength between the coating film and the wet base layer reaches 1.25-1.42 MPa; after alkali treatment, the bonding strength of the coating film and the base layer can still reach 1.24-1.3 MPa; after the water immersion treatment, the bonding strength of the coating film and the base layer can still reach 1.25-1.4 MPa.

(4) The water impermeability of the coating film of the polymer cement waterproof coating reaches 0.6 MPa, and the coating film is impermeable in 5 hours. The impermeability (mortar back surface) of the coating film reaches 0.8 MPa; the water absorption of the coating after soaking in water for 168 hours is only 3.5-3.7% (mass percent). The mechanical strength of the coating film is directly tested after the coating film is soaked in water for 168 hours, the length change of a test piece with the size of 120mm multiplied by 25mm is 0, the retention rate of tensile strength is more than 92%, the retention rate of elongation at break is more than 108%, the retention rate of adhesive strength is more than 95%, and the retention rate of adhesive strength of a wet base layer is more than 94%.

(5) The adhesive strength of the polymer cement waterproof mortar on the surface of a coating film of the waterproof coating reaches 1.2-1.3 MPa.

In conclusion, the invention achieves the remarkable effects of low water absorption, high water resistance, water resistance and no hydrophobicity, and no VOC release.

Detailed Description

Example 1 high-water-resistance polymer cement waterproof coating and preparation process thereof

The preparation process comprises the following steps:

step 1, preparing a nano silicon dioxide solution:

the preparation formula is as follows:

the preparation process comprises the following steps:

(1) preparing a solution a: respectively weighing 4.5 parts of tetraethoxysilane and 40.5 parts of absolute ethyl alcohol in a container, and uniformly mixing to prepare an ethyl orthosilicate ethanol solution with the mass fraction of 10%;

(2) preparing solution b, namely respectively weighing 9 parts of strong ammonia water, 25 parts of pure water and 21 parts of absolute ethyl alcohol in a container, and starting stirring, wherein the stirring speed is 900 rpm;

(3) quickly adding the solution a into the solution b, reducing the stirring speed to 400rpm after 5min, and keeping the rotating speed for reacting for 1h to obtain a solution c;

(4) and distilling the obtained solution c at the rotating speed of 300rpm to obtain a solution d, namely a nano silicon dioxide solution. The mass of the solution d obtained after distillation was 10% of the mass of the solution c. In the solution d, the mass percentage of the nano silicon dioxide is 12%.

Step 2, preparing liquid material:

the liquid material of the high-water-resistance polymer cement waterproof coating comprises the following components in parts by mass:

the styrene-butadiene emulsion comprises the following components: the glass transition temperature is-20 ℃;

the titanate coupling agent is a monoalkoxy pyrophosphate titanate coupling agent.

The following preparation process is adopted: stirring the nano silicon dioxide solution prepared in the step 1 at the speed of 800rpm, adding a titanate coupling agent at a constant speed for 2 minutes, reducing the rotating speed to 600rpm after stirring for 10 minutes, sequentially adding a butylbenzene emulsion, a polyacrylic acid sodium salt, an organic silicon defoamer and an isothiazolinone preservative, and stirring until the materials are uniformly mixed.

Step 3, preparing powder:

the powder material of the high-water-resistance polymer cement waterproof coating comprises the following components in parts by mass:

the preparation process comprises the following steps: mixing the above powder materials uniformly.

When in use, the liquid material and the powder material are mixed according to the ratio of 1:1.4 in mass ratio.

Example 2 high-water-resistance polymer cement waterproof coating and preparation process thereof

The preparation process comprises the following steps:

step 1, preparing a nano silicon dioxide solution:

prepared by the method of preparing the nano-silica solution of example 1.

Step 2, preparing liquid materials:

the styrene-butadiene emulsion comprises the following components: the glass transition temperature is-15 ℃;

the titanate coupling agent is a ligand type titanate coupling agent.

The preservative is benzimidazole preservative.

The following preparation process is adopted: stirring the nano silicon dioxide solution prepared in the step 1 at the speed of 900rpm, adding the titanate coupling agent at a constant speed for 3 minutes, reducing the rotating speed to 650rpm after stirring for 8 minutes, sequentially adding the butylbenzene emulsion, the polyacrylic acid sodium salt dispersing agent, the organic silicon defoaming agent and the preservative, and stirring until the mixture is uniformly mixed.

Step 3, preparing powder:

the invention relates to a powder material of a high-water-resistance polymer cement waterproof coating, which comprises the following components in parts by mass:

the preparation process comprises the following steps: mixing the above powder materials uniformly.

When in use, the liquid material and the powder material are mixed according to the ratio of 1:1.4 in mass ratio.

Example 3 high-water-resistance polymer cement waterproof coating and preparation process thereof

The preparation process comprises the following steps:

step 1, preparing a nano silicon dioxide solution:

prepared by the method of preparing the nano-silica solution of example 1.

Step 2, preparing liquid materials:

the styrene-butadiene emulsion comprises the following components: the glass transition temperature is-5 ℃;

the titanate coupling agent is a ligand type titanate coupling agent.

The preservative is a phentriazine preservative.

The following preparation process is adopted: stirring the nano silicon dioxide solution prepared in the step 1 at the speed of 700rpm, adding the titanate coupling agent at a constant speed for 2 minutes, reducing the rotating speed to 550rpm after stirring for 8 minutes, sequentially adding the butylbenzene emulsion, the polyacrylic acid sodium salt dispersing agent, the organic silicon defoaming agent and the preservative, and stirring until the mixture is uniformly mixed.

Step 3, preparing powder:

the powder material of the high-water-resistance polymer cement waterproof coating comprises the following components in parts by mass:

the preparation process comprises the following steps: mixing the above powder materials uniformly.

When in use, the liquid material and the powder material are mixed according to the ratio of 1:1.4 in mass ratio.

In examples 1-3, the concentration of the concentrated ammonia water is 25%; the purity of the ethyl orthosilicate is more than 96 percent; the purity of the absolute ethyl alcohol is 99.5 percent; the styrene-butadiene emulsion comprises the following components: the glass transition temperature is-15 ℃;

comparative example 1 Polymer Cement Water-proofing paint

Compared with the example 1, the comparative example uses styrene-acrylic emulsion to replace butylbenzene emulsion, uses 600-mesh heavy calcium to replace 600-mesh zeolite powder, does not use silicon dioxide solution and titanate coupling agent, and has the same preparation method as the example 1; the components of the liquid material and the powder material of the comparative example are as follows:

comparative example 2 Polymer Cement Water-proofing paint

Compared with the example 1, the comparative example is added with the hydrophobic agent, styrene-butadiene emulsion is replaced by styrene-acrylic emulsion, 600-mesh heavy calcium is replaced by 600-mesh zeolite powder, and a silicon dioxide solution and a titanate coupling agent are not used, and the preparation method is the same as that of the example 1;

the components of the liquid material and the powder material of the comparative example are as follows:

the polymer cement waterproof coating prepared in the above examples 1 to 3 and comparative examples 1 to 2 was prepared according to the following liquid materials: coating is carried out according to the mass ratio of powder =1:1.4, performance detection is carried out according to industry relevant standards, and the detection result is shown in the following table:

in the above table, performance detection is performed according to GB/T23445-.

As can be seen from the above table, the performance of the high-water-resistance polymer cement waterproof coating is higher than that of GB/T23445-. Compared with the comparative example 1, the product of the invention has the advantages that the water absorption rate is lower than 4 percent after being soaked in water for 7 days, the tensile property retention rate is more than 90 percent, the waterproof property is not attenuated, the water absorption expansion is avoided, and the product has excellent waterproof property; the comparative example 2 obviously weakens the bonding property of the follow-up mortar due to the existence of the hydrophobic agent, and compared with the comparative example 2, the product of the invention can maintain the follow-up bonding property while resisting water, thereby realizing the effect of resisting water and not hydrophobic.

As can be seen from the above table, the polymer cement waterproof coating has high bonding strength between the coating film and the base layer, and the bonding strength between the coating film and the wet base layer reaches 1.25-1.42 MPa; after alkali treatment, the bonding strength of the coating film and the base layer can still reach 1.24-1.3 MPa; after the water immersion treatment, the bonding strength of the coating film and the base layer can still reach 1.25-1.4 MPa. The water impermeability of the coating film of the polymer cement waterproof coating reaches 0.6 MPa, and the coating film is impermeable in 5 hours. The impermeability (mortar back surface) of the coating film reaches 0.8 MPa; the water absorption of the coating after soaking in water for 168 hours is only 3.5-3.7% (mass percent). The mechanical strength of the coating film is directly tested after the coating film is soaked in water for 168 hours, the length change of a test piece with the size of 120mm multiplied by 25mm is 0, the retention rate of tensile strength is more than 92%, the retention rate of elongation at break is more than 108%, the retention rate of adhesive strength is more than 95%, and the retention rate of adhesive strength of a wet base layer is more than 94%. The adhesive strength of the polymer cement waterproof mortar on the surface of a coating film of the waterproof coating reaches 1.2-1.3 MPa.

The waterproof coating disclosed by the invention does not release VOC (volatile organic compounds) in the using process after being mixed with cement. The traditional waterproof coating adopts styrene-acrylic emulsion, and VOC is easily released in the using process after the styrene-acrylic emulsion is mixed with cement; is harmful to the environment and human health.

Except for special description, the proportions are mass ratios, and the percentages are mass percentages.

In conclusion, the invention effectively solves the problem that the common polymer cement waterproof coating has poor water resistance and cannot be applied to the environment with long-term water immersion. It is clear that many variants are possible within the inventive idea, and that any changes made within the inventive idea shall be deemed to fall within the scope of protection of the invention.