Composition for seal primer, seal primer as well as preparation method and application of seal primer

Abstract

The invention relates to the field of building waterproof materials, and discloses a composition for a seal primer, the seal primer and a preparation method and application of the seal primer, the composition contains a component A and a component B in a weight ratio of 1: (1.8-2), the component A is composed of a first main agent and a first auxiliary agent, and the first main agent is styrene-acrylic emulsion and silica sol in a weight ratio of 100: (9-12); the glass transition temperature of the styrene-acrylic emulsion is-9 DEG C to-6 DEG C, and the solid content of the styrene-acrylic emulsion is 53%-56%; the concentration of the silica sol in terms of silicon dioxide is 20-35 wt%, and the average particle diameter is 10-30 nm; the component B is composed of a second main agent and a second auxiliary agent; the second main agent is prepared from a basic component, cellulose ether, polypropylene fiber and filler in a weight ratio of 100: (0.12-0.16): (0.3-0.42): (120-160); the basic component comprises Portland cement, sulfur aluminum cement and gypsum according to a weight ratio of (25-45): (4-6): 1. The seal primer provided by the invention has the advantages of quick drying, crack resistance and excellent adhesive property.

Description

Technical Field

[0001] The present invention relates to the field of building waterproof materials, and particularly to a composition for a sealing primer, a sealing primer, a preparation method thereof, and an application thereof. Background Art

[0002] The surfaces of concrete, aerated concrete, lime-sand bricks, fly ash bricks, etc. have strong water absorption and many voids. If a plaster layer or a waterproof coating is directly applied on these substrates without treatment, the air inside the voids will be squeezed when the ash layer or the coating is applied on the substrate surface. Due to the extrusion of air, this process is likely to cause problems such as bubbles or pinholes in the waterproof layer. At the same time, it will also cause quality defects such as the hollowing and peeling of the mortar plaster layer, or the appearance of pinholes, craters, etc. when applying the waterproof coating. Moreover, if the substrate is too smooth, it will also cause difficult interfacial adhesion, resulting in problems such as the hollowing, cracking, and peeling of the plaster layer.

[0003] Therefore, an interface agent is needed to treat walls such as concrete, aerated concrete, and fly ash blocks, enhance the adhesion between new and old concretes and between the concrete and the waterproof coating, be able to replace the traditional roughening process, enhance the bonding strength between the concrete substrate and the waterproof coating, seal the voids on the wall surface, reduce the water absorption rate of the wall surface, and avoid problems such as pinholes and peeling in the waterproof layer.

[0004] Currently, those skilled in the art often use emulsion-type wall strengthening agents or cement substrate treatment agents to solve the above problems.

[0005] Specifically, emulsion-type wall strengthening agents are generally polymer emulsions such as styrene-acrylate emulsion, polyvinyl alcohol emulsion, and EVA emulsion. The polymers in such strengthening agents can penetrate into the voids inside the concrete substrate. After film formation, the polymers can fill the voids of the substrate, reduce the water absorption rate of the substrate surface, and reduce the pinhole problems that occur during the subsequent waterproof layer construction. At the same time, it can also wrap the loose parts on the substrate surface, play a strengthening effect on the substrate. At the same time, after the strengthening agent is mixed with cement and applied on the substrate surface, it has a roughening effect, increases the adhered area of the substrate, and improves the substrate bonding strength. However, the solid content of such products is low, and the filling and sealing of the substrate voids are not sufficient to seal all the voids, resulting in the appearance of pinholes in the subsequent waterproof layer. In addition, the apparent hardness of such organic strengthening agents is low, and the effect of enhancing the surface bonding strength is poor.

[0006] Cement substrate treatment agents generally consist of cement, sand, heavy calcium, and rubber powder. The rubber powder is a macromolecular polymer that can penetrate into the voids inside the substrate to fill the voids. The mutual wrapping of cement and rubber powder to form a film can provide excellent apparent hardness for the substrate surface and increase the interfacial bonding strength. However, such products have strong sealing properties and cannot be thickly applied. Thick application is likely to cause shrinkage cracking. The products do not have a leveling function, and the traditional portland cement has a slow curing time, so the surface drying time of the products is long, which affects the construction of the next process.

[0007] CN117343582A discloses a composition for preparing an adhesive coating, an adhesive coating, a preparation method and an application thereof. The composition contains Component A and Component B, and the mass ratio of the content of Component A to that of Component B is 1: 0.2-3.5; based on the total mass of Component A, Component A contains water, styrene-acrylic emulsion, silica sol aqueous solution, styrene-butadiene emulsion, defoamer I and preservative; based on the total mass of Component B, Component B contains portland cement, active filler, quartz sand, heavy calcium carbonate, calcium hydroxide, sodium sulfate, cellulose ether, water reducer and defoamer II; the active filler is a combination of metakaolin and ore powder with a mass ratio of 1: 1.8-2.2. The obtained adhesive coating can effectively realize the functions of waterproof coating, wall fixing emulsion and tile back adhesive. During use, the compatibility, affinity and bonding strength between product interfaces are extremely strong. However, this product mainly solves traditional waterproof problems. In the tiling process, three different materials, namely waterproof coating, wall fixing emulsion and tile back adhesive, are used. The affinity of these three materials is poor and the bonding performance is relatively poor. Moreover, the surface drying time of this product is relatively long, which affects the construction progress. At the same time, there are also problems of cracking after thick coating, low product viscosity, low brushing thickness and no leveling function.

[0008] Therefore, it is of great significance to develop a quick-drying, crack-resistant and leveling multi-functional primer. Summary of the Invention

[0009] The purpose of the present invention is to solve the problems of long surface drying time, easy cracking of the coating and no leveling function existing in the primer in the prior art.

[0010] To achieve the above purpose, in the first aspect of the present invention, a composition for a primer is provided. The composition contains Component A and Component B with a weight ratio of 1: 1.8-2.

[0011] Component A is composed of a first main agent and a first auxiliary agent. The first main agent is a styrene-acrylic emulsion and silica sol with a weight ratio of 100: 9-12; the glass transition temperature of the styrene-acrylic emulsion is -9 °C to -6 °C, and the solid content of the styrene-acrylic emulsion is 53%-56%; the concentration of the silica sol in terms of silicon dioxide is 20-35 wt%, and the average particle diameter is 10-30 nm.

[0012] Component B is composed of a second main agent and a second auxiliary agent. The second main agent is a basic component, cellulose ether, polypropylene fiber and filler with a weight ratio of 100: 0.12-0.16: 0.3-0.42: 120-160; the basic component is a combination of portland cement, sulfoaluminate cement and gypsum with a weight ratio of 25-45: 4-6: 1; the filler is a combination of quartz sand, heavy calcium carbonate and mica powder with a weight ratio of 3.5-4.5: 6-7: 1.

[0013] In the second aspect of the present invention, a method for preparing a sealing primer is provided. This method is carried out using the components in the composition described in the first aspect above. This method includes:

[0014] (1) Preparing a liquid agent and a powder

[0015] The method for preparing the liquid agent includes: making a first contact between a first main agent and a first auxiliary agent to obtain the liquid agent;

[0016] The method for preparing the powder includes: making a second contact between a second main agent and a second auxiliary agent to obtain the powder;

[0017] (2) Making a third contact between the liquid agent and the powder in an amount ratio by weight of 1:1.8 - 2 to obtain the sealing primer.

[0018] In the third aspect of the present invention, a sealing primer prepared by the method described in the second aspect above is provided.

[0019] In the fourth aspect of the present invention, the application of the sealing primer described in the third aspect above in the field of building waterproofing is provided.

[0020] The technical solution of the present invention has at least the following advantages:

[0021] (1) The sealing primer provided by the present invention has excellent permeability, sealing property and bonding property. Therefore, the coating after construction of this sealing primer is not easy to crack and has the function of leveling.

[0022] (2) The surface drying time of the sealing primer provided by the present invention is short, which can effectively save labor costs and improve construction efficiency. Description of the Drawings

[0023] Figure 1 is the base layer diagram after waterproof construction using the sealing primer provided in Example 1 of the present invention;

[0024] Figure 2 is the base layer diagram after waterproof construction without using the sealing primer provided by the present invention. Detailed Embodiments

[0025] The endpoints and any values within the ranges disclosed herein are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0026] As described above, the first aspect of the present invention provides a composition for a sealing primer, which composition contains component A and component B in a weight ratio of 1:1.8 - 2.

[0027] Component A is composed of a first main agent and a first auxiliary agent. The first main agent is a styrene-acrylic emulsion and silica sol with a weight ratio of 100:9 - 12; the glass transition temperature of the styrene-acrylic emulsion is -9°C to -6°C, and the solid content of the styrene-acrylic emulsion is 53% - 56%; the concentration of the silica sol in terms of silicon dioxide is 20 - 35 wt%, and the average particle diameter is 10 - 30 nm.

[0028] Component B is composed of a second main agent and a second auxiliary agent. The second main agent is a basic component, a cellulose ether, a polypropylene fiber, and a filler with a weight ratio of 100:0.12 - 0.16:0.3 - 0.42:120 - 160; the basic component is a Portland cement, a sulphoaluminate cement, and gypsum with a weight ratio of 25 - 45:4 - 6:1; the filler is a combination of quartz sand, heavy calcium carbonate, and mica powder with a weight ratio of 3.5 - 4.5:6 - 7:1.

[0029] Preferably, in component A, based on the total weight of component A, the content of the styrene-acrylic emulsion is 45 - 55 wt%, and the content of the silica sol is 4 - 6 wt%.

[0030] More preferably, in component A, the first auxiliary agent contains a dispersant, a preservative, a first defoamer, and a thickener.

[0031] Further preferably, based on the total weight of component A, the content of the dispersant is 0.2 - 0.4 wt%, the content of the preservative is 0.1 - 0.2 wt%, the content of the first defoamer is 0.1 - 0.3 wt%, and the content of the thickener is 0.1 - 0.3 wt%.

[0032] The present invention has no particular requirements for the types of the dispersant, the preservative, the first defoamer, and the thickener. Various dispersants, various preservatives, various defoamers, and various thickeners known and commonly used in the art can be used in the solution of the present invention. Exemplarily, the dispersant can be sodium polycarboxylate and / or ammonium polycarboxylate, the first defoamer can be a silicone defoamer and / or a mineral oil defoamer, and the thickener can be an acrylic alkali-swellable thickener.

[0033] Particularly preferably, component A further contains water. Based on the total weight of component A, the content of the water is 35 - 50 wt%.

[0034] Preferably, in the B component, based on the total weight of the B component, in the second main agent, the content of the base component is 35-50 wt%, the content of the cellulose ether is 0.05-0.07 wt%, the content of the polypropylene fiber is 0.12-0.18 wt%, and the content of the filler is 50-65 wt%.

[0035] According to a preferred specific embodiment, in the B component, the average particle diameter of the quartz sand in the filler is 120-180 μm, the average particle diameter of the heavy calcium carbonate is 60-90 μm, and the average particle diameter of the mica powder is 18-25 μm. The inventors of the present invention have found that under this specific embodiment, the sealing primer provided by the present invention has better bonding performance and leveling effect.

[0036] More preferably, in the B component, in the base component of the second main agent, the weight ratio of the contents of the portland cement, the sulfoaluminate cement, and the gypsum is 35-37:4.5-5.5:1. The inventors of the present invention have found that in this preferred case, the surface drying time of the sealing primer provided by the present invention is faster and it has more excellent crack resistance.

[0037] Further preferably, the strength grades of both the portland cement and the sulfoaluminate cement are 42.5R.

[0038] Even more preferably, in the B component, the second auxiliary agent contains a water reducing agent and a second defoaming agent.

[0039] Particularly preferably, based on the total weight of the B component, the content of the water reducing agent is 0.12-0.16 wt%, and the content of the second defoaming agent is 0.03-0.05 wt%.

[0040] The present invention has no particular requirements on the types of the water reducing agent and the second defoaming agent. Those skilled in the art can use various dispersants, various preservatives, various defoaming agents, and various thickeners known and commonly used in the art in the solution of the present invention. Exemplarily, the water reducing agent can be a melamine water reducing agent and / or a polycarboxylate water reducing agent, and the second defoaming agent can be a powder type silicone defoaming agent.

[0041] As described above, the second aspect of the present invention provides a method for preparing a sealing primer. This method is carried out using the components in the composition described in the first aspect above. This method includes:

[0042] (1) Preparing a liquid agent and a powder agent

[0043] The preparation method of the liquid agent includes: making a first contact between the first main agent and the first auxiliary agent to obtain the liquid agent;

[0044] The preparation method of the powder includes: subjecting the second main agent and the second auxiliary agent to a second contact to obtain the powder;

[0045] (2) Subjecting the liquid agent and the powder to a third contact at a weight ratio of 1:1.8 - 2 to obtain the sealing primer.

[0046] According to a preferred embodiment, in the preparation method of the liquid agent, the first contact further includes: first mixing water, styrene-acrylic emulsion, silica sol, dispersant, first defoamer, and thickener to obtain mixture I; and second mixing the mixture I with a preservative to obtain the liquid agent.

[0047] According to a more preferred embodiment, in the method for preparing the sealing primer, the conditions of the first contact, the second contact, and the third contact are each independently selected from: a rotation speed of 500 - 1500 rpm and a time of 10 - 25 min.

[0048] According to a particularly preferred embodiment, in the method for preparing the sealing primer, the conditions of the first contact include: a rotation speed of 500 - 1000 rpm and a time of 10 - 20 min; the conditions of the second contact include: a rotation speed of 500 - 1000 rpm and a time of 15 - 25 min; the conditions of the third contact include: a rotation speed of 1000 - 1500 rpm and a time of 15 - 25 min.

[0049] According to a particularly preferred specific embodiment, the method for preparing the sealing primer includes:

[0050] (1) Adding water, styrene-acrylic emulsion, silica sol, dispersant, first defoamer, and thickener into a dispersion tank, stirring and mixing at 500 - 1000 rpm for 5 - 10 min; then adding a preservative and continuing to stir for 5 - 10 min to obtain the liquid agent;

[0051] (2) Mixing portland cement, sulphoaluminate cement, gypsum, cellulose ether, polypropylene fiber, quartz sand, heavy calcium, mica powder, water reducer, and second defoamer, stirring and mixing at 500 - 1000 rpm for 15 - 25 min to obtain the powder;

[0052] (3) Stirring and mixing the liquid agent and the powder at 1000 - 1500 rpm for 15 - 25 min to obtain the sealing primer.

[0053] As described above, the third aspect of the present invention provides a sealing primer prepared by the method described in the foregoing second aspect.

[0054] As described above, the fourth aspect of the present invention provides the application of the sealing primer described in the foregoing third aspect in the field of building waterproofing.

[0055] The present invention will be described in detail below with reference to examples. In the following examples, various instruments and raw materials used are commercially available unless otherwise specified.

[0056] Some of the raw materials used in the following examples and their sources are as follows:

[0057] Styrene-acrylic emulsion: Styrene-acrylic emulsion-I, with a solid content of 54-56%, a glass transition temperature of -9 °C, and a grade of 7366, purchased from Foshan Shunde Badfu Industrial Co., Ltd.

[0058] Styrene-acrylic emulsion: Styrene-acrylic emulsion-II, with a solid content of 51-52%, a glass transition temperature of -9 °C, and a grade of 7117, purchased from Dongying Jinyoulai Industry and Trade Co., Ltd.

[0059] Silica sol: with a concentration of 24-25% (calculated as SiO2), an average particle diameter of 18 nm, and a grade of SW-25, purchased from Jinan Hongxinda Biotechnology Co., Ltd.

[0060] Dispersant: Sodium polycarboxylate, with a grade of TD-JSS2, purchased from Wuhan Desai New Building Materials Co., Ltd.

[0061] Preservative: Kathon preservative 15, purchased from Jinan Kathon Chemical Co., Ltd.

[0062] First defoamer: Organosilicon defoamer, with a grade of CI-0560, purchased from Guangdong Nanhui New Materials Co., Ltd.

[0063] Thickener: Acrylic alkali-swellable thickener, with a grade of A801, purchased from Wanhua Chemical Group Co., Ltd.

[0064] Portland cement: Strength grade 42.5R;

[0065] Sulphoaluminate cement: Strength grade 42.5R;

[0066] Quartz sand: Average particle diameter 150 μm;

[0067] Water reducer: Melamine water reducer, purchased from Jinan Qingtian Chemical Technology Co., Ltd.

[0068] Heavy calcium: Average particle diameter 75 μm, purchased from Jiaoling Jinpeng Fine Chemical Co., Ltd.

[0069] Mica powder: Mica powder-I, average particle diameter 25 μm, purchased from Chuzhou Baota Sericite Mining Co., Ltd.

[0070] Mica powder: Mica powder-II, average particle diameter 15 μm, purchased from Chuzhou Baota Sericite Mining Co., Ltd.

[0071] Cellulose ether: Methyl cellulose ether, grade SC-60M, viscosity of 2% aqueous solution at 25°C is 5200 mPa·S, purchased from Aohanshengchuan Chemical Industry (Beijing) Co., Ltd.;

[0072] Polypropylene fiber: Fiber length is 6 mm, purchased from Shandong Hongju Engineering Materials Co., Ltd.;

[0073] Second defoamer: Powdered silicone defoamer, grade B-290, purchased from Guangdong Zhongke Hongtai New Materials Co., Ltd.

[0074] The component dosages in the following examples are all expressed in parts by weight. Without special instructions, each part by weight is 100 g.

[0075] Example 1

[0076] (1) Add water, styrene-acrylic emulsion, silica sol, dispersant, first defoamer, and thickener into the dispersion tank, and stir and mix at 800 rpm for 10 min; then add preservative and continue to stir for 10 min to obtain the liquid agent;

[0077] (2) Mix portland cement, sulphoaluminate cement, gypsum, cellulose ether, polypropylene fiber, quartz sand, heavy calcium, mica powder, water reducer, and second defoamer, and stir and mix at 800 rpm for 20 min to obtain the powder agent;

[0078] (3) Stir and mix the liquid agent and the powder agent according to the ratio at 1000 rpm for 20 min to obtain the sealing primer.

[0079] Without special instructions, the following examples are carried out according to the method of Example 1. The difference is that the types and dosages of raw materials used in the other examples are different. See Table 1 for details.

[0080] Table 1

[0081]

[0082]

[0083] Example 4

[0084] It is carried out by a method similar to that of Example 1. The difference is that while keeping the total dosage of the basic components in Component B unchanged, the weight ratio of portland cement, sulphoaluminate cement, and gypsum is adjusted to portland cement:sulphoaluminate cement:gypsum = 34:6:1.

[0085] Example 5

[0086] It is carried out by a method similar to that of Example 1. The difference is that mica powder-I in Component B is replaced with an equal weight of mica powder-II.

[0087] Comparative Example 1

[0088] It was carried out in a similar method to Example 1, except that the amount of styrene-acrylic emulsion in Component A was adjusted to 620 parts by weight, and the amount of water was adjusted to 321.5 parts by weight.

[0089] Comparative Example 2

[0090] It was carried out in a similar method to Example 1, except that styrene-acrylic emulsion-I in Component A was replaced with an equal weight of styrene-acrylic emulsion-II.

[0091] Comparative Example 3

[0092] It was carried out in a similar method to Example 1, except that the total amount of the basic components in Component B was kept unchanged, gypsum was not added, and the weight ratio of Portland cement to sulfoaluminate cement was Portland cement:sulfoaluminate cement = 35:6.

[0093] Comparative Example 4

[0094] It was carried out in a similar method to Example 1, except that the total amount of fillers in Component B was kept unchanged, and the weight ratio of quartz sand, heavy calcium carbonate, and mica powder was adjusted to quartz sand:heavy calcium carbonate:mica powder = 3:6:1.

[0095] Test Example

[0096] The mechanical properties of the sealant primers obtained in the above examples were tested according to the standard JC / T 907-2018 "Concrete Interface Treatment Agent", and the technical performance of the sealant primers obtained in the present invention was evaluated with reference to the technical requirements of Type I in the standard;

[0097] Surface drying time: The test was carried out according to Method B in 7.2.2 of GB / T 1728-2020;

[0098] Actual drying time: The test was carried out according to Method C in 7.3.3 of GB / T 1728-2020;

[0099] Elongation at break: It was formed according to 7.4.2 of GBT 23445-2009 and determined according to 9.2.1 of GBT 16777-2008.

[0100] The specific test results are shown in Table 2.

[0101] Table 2

[0102]

[0103] As can be seen from the results in Table 2, the sealing primer provided by the present invention has a fast surface drying time, excellent adhesion performance and crack resistance, and its excellent mechanical properties meet the requirements for Type I interface treatment agents in the JCT 907-2018 "Concrete Interface Treatment Agent" standard. In addition, Figure 1 is the base layer for waterproof construction after using the sealing primer provided in Example 1 of the present invention, Figure 2 is the base layer for waterproof construction without using the sealing primer provided by the present invention. By comparing Figure 1 with Figure 2 the displayed effects, it can be seen that Figure 1 there are no obvious pinholes in the waterproof coating in Figure 2 while there are many obvious pinholes in the waterproof coating in

[0104] This indicates that the sealing primer provided by the present invention has excellent sealing performance, can effectively reduce the water absorption rate of the base layer, and avoid the pinhole problem in the base layer waterproof construction. The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A sealing primer composition, characterized in that: The composition contains component A and component B in a weight ratio of 1:1.8-2. The component A is composed of a first main agent and a first auxiliary agent, wherein the first main agent is a styrene-acrylic emulsion and a silica sol in a weight ratio of 100:9-12; the glass transition temperature of the styrene-acrylic emulsion is -9°C to -6°C, and the solid content of the styrene-acrylic emulsion is 53%-56%; the concentration of the silica sol in terms of silicon dioxide is 20-35wt%, and the average particle diameter is 10-30nm; The B component is composed of a second main agent and a second auxiliary agent, wherein the second main agent is a basic component, cellulose ether, polypropylene fiber and filler in a weight ratio of 100:0.12-0.16:0.3-0.42:120-160; the basic component is silicate cement, sulfoaluminum cement and gypsum in a weight ratio of 25-45:4-6:1; the filler is a combination of quartz sand, heavy calcium and mica powder in a weight ratio of 3.5-4.5:6-7:

1.

2. The composition according to claim 1, wherein In the component A, based on the total weight of the component A, the content of the styrene-acrylic emulsion is 45-55wt%, and the content of the silica sol is 4-6wt%.

3. The composition according to claim 1 or 2, wherein In the component A, the first auxiliary agent contains a dispersant, a preservative, a first defoamer and a thickener; And / or, based on the total weight of the A component, the content of the dispersant is 0.2-0.4wt%, the content of the preservative is 0.1-0.2wt%, the content of the first defoamer is 0.1-0.3wt%, and the content of the thickener is 0.1-0.3wt%; And / or, based on the total weight of the component A, the component A further contains 35-50 wt % of water.

4. The composition according to claim 1 or 2, wherein In the B component, based on the total weight of the B component, in the second main agent, the content of the base component is 35-50wt%, the content of the cellulose ether is 0.05-0.07wt%, the content of the polypropylene fiber is 0.12-0.18wt%, and the content of the filler is 50-65wt%.

5. The composition according to claim 1 or 2, wherein In the B component, in the base component of the second main agent, the weight ratio of the silicate cement, the sulphoaluminium cement and the gypsum is 35-37:4.5-5.5:1; Preferably, the strength grade of the silicate cement and the sulphoaluminium cement are both 42.5R.

6. The composition according to claim 1 or 2, wherein In the B component, the second auxiliary agent contains a water reducing agent and a second defoaming agent; And / or, based on the total weight of the B component, the content of the water reducing agent is 0.12-0.16wt%, and the content of the second defoaming agent is 0.03-0.05wt%.

7. A method for preparing a closed primer, characterized in that: The method is carried out using the components in the composition according to any one of claims 1 to 6, and the method comprises: (1) Preparation of liquid and powder The preparation method of the liquid agent comprises: bringing a first main agent into first contact with a first auxiliary agent to obtain the liquid agent; The preparation method of the powder comprises: bringing a second main agent and a second auxiliary agent into second contact to obtain the powder; (2) The liquid and the powder are brought into contact with each other in a weight ratio of 1:1.8-2 to obtain the sealing primer.

8. The method according to claim 7, wherein: The conditions of the first contact, the second contact and the third contact are independently selected from: a rotation speed of 500-1500 rpm and a time of 10-25 min.

9. The closed primer prepared by the method described in claim 7 or 8.

10. Use of the sealing primer according to claim 9 in the field of building waterproofing.

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