A self-leveling penetration crystalline waterproof coating and a preparation method thereof

Abstract

The application discloses a kind of self-leveling penetration crystallization waterproof coating and preparation method thereof, the waterproof coating includes component A and component B, component A includes water and polyvinyl alcohol, component B includes cement, quartz sand, active crystallization chemical and tartaric acid, when preparing, component A and component B are respectively prepared;The components in component A are uniformly mixed to prepare component A;The components in component B are uniformly mixed to prepare component B, when using, component A and B can be mixed;The waterproof coating can realize the full penetration of active crystallization substance by self-locking water without curing process, which can improve the waterproof performance of concrete base layer and form a self-waterproof layer, can close the concrete and external ventilation channel, prevent the construction of the next waterproof or decorative coating Bubble is generated, also has excellent self-leveling performance, can easily realize leveling function to concrete foundation, for example, waterproofing membrane can be directly laid on it, without additional polishing leveling operation.

Description

[0001] This invention is a divisional application of Chinese invention patent application filed on April 28, 2023, with application number 2023104737177 and title "A self-leveling penetrating crystallizing waterproof coating and its application". Technical Field

[0002] This invention relates to the field of waterproof materials technology, specifically to a self-leveling penetrating crystallizing waterproof coating and its preparation method. Background Technology

[0003] Cement-based penetrating crystalline waterproof coatings are powdered rigid waterproof materials made from cement, quartz sand, and other base materials, mixed with active chemical substances. When used, they are mixed with water to form a slurry, applied to the cement concrete substrate, and after curing, form a rigid, adherent coating on the concrete surface. Ideally, the active chemical substances in the coating penetrate into the concrete through a water-penetrating carrier, catalyzing the silicates in the concrete to form water-insoluble crystals. These crystals fill and block capillary pores and micro-cracks, thereby densifying the concrete and achieving enhanced impermeability and waterproof protection. However, current penetrating crystalline waterproof coatings have at least the following problems after application:

[0004] First, the coating formed by brushing is prone to powdering. On the one hand, this prevents the active crystalline substances from fully penetrating into the concrete base layer. The concrete base layer is not dense and has many pores, which poses a risk of leakage. At the same time, the gas remaining in the pores can easily cause bubbles to form when applying the next layer of waterproofing or decorative coating. On the other hand, the coating cannot form its own waterproof function and needs to rely on the concrete material in the foundation structure to produce a waterproof function.

[0005] Secondly, after the coating is applied, additional curing is required (usually around one week. The purpose of curing is to provide sufficient time and replenish carrier water so that the active crystalline substances can fully penetrate into the concrete base). If curing is not carried out and the next process, such as laying waterproof membrane, is carried out directly, it will be difficult for the underlying coating to obtain additional moisture. The existing coating itself is prone to losing water and turning into powder. Without a carrier, the active crystalline substances will also be unable to fully penetrate into the concrete base. Therefore, existing penetrating crystalline waterproof coatings basically require curing, which makes the construction cycle longer.

[0006] Third, after the existing coating is cured, it needs to be leveled before the next process, such as laying waterproof membrane, is required. Otherwise, insufficient flatness can easily cause gaps between the waterproof membrane and the coating, leading to water seepage. Summary of the Invention

[0007] The purpose of this invention is to overcome one or more shortcomings in the prior art and provide an improved method for preparing a penetrating crystalline waterproof coating and the waterproof coating made therefrom. This waterproof coating can not only achieve full penetration of active crystalline substances without curing through self-locking water, thus improving the waterproof performance of the concrete substrate and forming its own waterproof layer, but also seals the ventilation channels between the concrete and the outside, preventing the formation of air bubbles during the construction of subsequent waterproof or decorative coatings. Moreover, it has excellent self-leveling properties, which can easily achieve the leveling function of the concrete foundation, facilitating the application and construction of other materials. For example, waterproof membranes can be laid directly without additional grinding and leveling operations.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] A method for preparing a self-leveling, penetrating, crystalline waterproof coating, the waterproof coating comprising component A and component B, wherein component A contains water, and the preparation method includes:

[0010] Preparation of component A:

[0011] By mass percentage, component A further contains 10%-20% polyvinyl alcohol, and component A does not contain any other film-forming resins besides polyvinyl alcohol; the degree of polymerization of the polyvinyl alcohol is 400-2000, and the degree of alcoholysis is greater than 70%.

[0012] The components in component A are mixed evenly to obtain component A;

[0013] Preparation of component B:

[0014] Component B comprises cement, quartz sand, active crystalline chemical substance and tartaric acid, wherein tartaric acid accounts for 0.1%-0.8% by mass percentage in component B.

[0015] The components in component B are mixed evenly to obtain component B.

[0016] In the waterproof coating, the mass ratio of component A to component B is 1:0.6-1.

[0017] Another technical solution provided by the present invention: a self-leveling penetrating crystallizing waterproof coating, the waterproof coating comprising component A and component B, wherein component A contains water, and component B contains a base material and an active crystallizing chemical substance, wherein: by mass percentage, component A further contains 10%-20% polyvinyl alcohol (PVA), and component A does not contain any other film-forming resins other than polyvinyl alcohol.

[0018] Component B also contains 0.1%-0.8% tartaric acid by weight percentage.

[0019] According to some preferred aspects of the invention, component A contains 15%-20% polyvinyl alcohol by mass percentage; and component B contains 0.2%-0.6% tartaric acid by mass percentage.

[0020] According to some preferred aspects of the invention, the degree of polymerization of the polyvinyl alcohol is 400-2000, and the degree of hydrolysis is greater than 70%.

[0021] According to some preferred aspects of the present invention, the polyvinyl alcohol is composed of a first polyvinyl alcohol and a second polyvinyl alcohol, wherein the mass ratio of the first polyvinyl alcohol to the second polyvinyl alcohol is 0.8-2:1, the degree of polymerization of the first polyvinyl alcohol is 1500-2000, and the degree of hydrolysis is 75%-95%; the degree of polymerization of the second polyvinyl alcohol is 500-800, and the degree of hydrolysis is 98%-100%.

[0022] According to some preferred aspects of the present invention, the active crystalline chemical substance is composed of 1000-1500 mesh metakaolin, 3500-4500 mesh metakaolin, and 600-1000 mesh silica fume, wherein the mass ratio of the 1000-1500 mesh metakaolin, the 3500-4500 mesh metakaolin, and the 600-1000 mesh silica fume is 2.5-3.5:0.6-1.2:1.

[0023] According to some preferred aspects of the present invention, the mass ratio of component A to component B is 1:0.6-1.

[0024] According to some preferred aspects of the invention, component A comprises, by weight percentage, 10%-20% polyvinyl alcohol, 78%-90% water, 0-1% defoamer, and 0-1% preservative.

[0025] Furthermore, by mass percentage, component A comprises 15%-20% polyvinyl alcohol, 78%-84% water, 0.05-1% defoamer, and 0.05-1% preservative.

[0026] In some embodiments of the present invention, the defoamer includes one or more of mineral oils, polyethers, and polysiloxanes.

[0027] In some embodiments of the present invention, the preservative includes one or more of isothiazolinones, substituted aromatic hydrocarbons, and organic amines.

[0028] According to some preferred aspects of the invention, the base material comprises cement and quartz sand;

[0029] By mass percentage, component B comprises 30%-35% cement, 30%-50% quartz sand, 15%-35% active crystalline chemical substance, 0.1%-0.8% tartaric acid, 0.1%-0.25% polycarboxylate superplasticizer, and 0.05%-0.2% bentonite.

[0030] In some embodiments of the present invention, the polycarboxylate superplasticizer includes one or both of BASF 2651F and Sika 325C.

[0031] Another technical solution provided by the present invention: an application of the above-described self-leveling penetrating crystallizing waterproof coating to prepare a waterproof coating on a concrete substrate.

[0032] According to some preferred aspects of the present invention, after the above-described self-leveling penetrating crystalline waterproof coating is applied to the concrete substrate to form a waterproof coating, the curing and leveling processes are omitted, and the waterproof membrane is directly applied.

[0033] Another technical solution provided by the present invention: a method for preparing the above-mentioned self-leveling penetrating crystallizing waterproof coating, the preparation method comprising:

[0034] Preparation of component A: Mix all components in component A to obtain the desired product;

[0035] Preparation of component B: Mix all components in component B to obtain the desired result;

[0036] Waterproof coating can be obtained by mixing component A and component B according to the formula ratio.

[0037] In some embodiments of the present invention, during the preparation of component A, each component in component A is weighed according to the formula, added to a temperature-controlled stirring vessel, and stirred for 40-60 minutes at a water temperature of 85-95°C and a stirrer at 600-1000 rpm.

[0038] In some embodiments of the present invention, during the preparation of component B, each component of component B is weighed according to the formula, and 40%-60% of cement, 40%-60% of quartz sand, and 40%-60% of 1200-mesh metakaolin are added sequentially to a horizontal dry mortar mixer. Then, other components except cement, quartz sand, and 1200-mesh metakaolin are added, and stirring is continued. Then, the remaining cement, remaining quartz sand, and remaining 1200-mesh metakaolin are added and stirred until homogeneous to obtain the final product.

[0039] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0040] Based on the problems of existing penetrating crystalline waterproof coatings, the inventors of this invention provide a solution that addresses the issues of easy powdering, the need for separate curing, and the requirement for additional grinding and leveling of the resulting coating. This invention innovatively uses polyvinyl alcohol (PVA) as an independent film-forming resin (component A) and controls its addition amount. Simultaneously, tartaric acid is added to component B. This results in a penetrating crystalline waterproof coating with excellent self-leveling properties and a self-locking water function, preventing the lack of water channels for the active crystalline chemicals to penetrate and modify the base concrete after water curing. Furthermore, by utilizing PVA as a film-forming substance and also forming water-retaining channels, it achieves the function of penetrating and crystallizing without the need for curing. Simultaneously, it provides a structural layer with a certain mechanical strength, sealing the ventilation channels between the concrete and the outside, and preventing the formation of air bubbles during the construction of subsequent waterproofing or decorative coatings. This material of the present invention can achieve self-waterproofing performance of modified concrete structures and form a waterproof layer itself. One material forms two waterproof structures, improving the waterproofing quality. In addition, the advantage of good self-leveling performance also allows the waterproof coating to easily achieve the leveling function of the concrete base, facilitating the application and construction of other materials. For example, waterproof membranes can be laid directly without additional grinding and leveling operations. Detailed Implementation

[0041] The above-mentioned solution will be further described below with reference to specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions used in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0042] Unless otherwise specified in the following examples, all raw materials are commercially available or prepared by conventional methods in the art.

[0043] Example 1

[0044] This example provides a self-leveling penetrating crystallizing waterproof coating, which includes component A and component B. The mass ratio of component A to component B is 1:0.6. The specific raw material formula is shown in Table 1 below.

[0045] Table 1

[0046]

[0047]

[0048] The method for preparing the self-leveling penetrating crystallizing waterproof coating includes:

[0049] Preparation of component A: Weigh each component in component A, add them to a temperature-controlled stirring vessel, and stir at 1000 rpm for 60 minutes at a water temperature of 90℃.

[0050] Preparation of component B: Weigh each component of component B, and add 50% of cement, 50% of quartz sand, and 50% of 1200 mesh metakaolin to a horizontal dry mortar mixer in sequence. Then add the other components except cement, quartz sand, and 1200 mesh metakaolin, continue mixing, and then add the remaining cement, remaining quartz sand, and remaining 1200 mesh metakaolin, mix well, and obtain the final product.

[0051] By mixing component A and component B according to the formula ratio, a self-leveling penetrating crystalline waterproof coating can be obtained.

[0052] Example 2

[0053] This example provides a self-leveling penetrating crystallizing waterproof coating, which includes component A and component B. The mass ratio of component A to component B is 1:0.8. The specific raw material formula is shown in Table 2 below.

[0054] Table 2

[0055]

[0056]

[0057] The preparation method is the same as in Example 1.

[0058] Example 3

[0059] This example provides a self-leveling penetrating crystallizing waterproof coating, which includes component A and component B. The mass ratio of component A to component B is 1:1.0. The specific raw material formula is shown in Table 3 below.

[0060] Table 3

[0061]

[0062] The preparation method is the same as in Example 1.

[0063] Comparative Example 1

[0064] The basic structure is the same as in Example 1, except that in component A, "polyvinyl alcohol" is completely replaced with acrylate of the same mass percentage.

[0065] Comparative Example 2

[0066] The composition is basically the same as in Example 1, except that in component A, "4% polyvinyl alcohol PVA-1788 and 5% polyvinyl alcohol BP-0599" are replaced with 9% acrylate. That is, after adjustment, component A contains 4% polyvinyl alcohol PVA-1788, 5% polyvinyl alcohol BP-0599, 9% acrylate, 81.5% water, 0.3% defoamer, and 0.2% preservative.

[0067] Comparative Example 3

[0068] The method is basically the same as in Example 1, except that the amount of "polyvinyl alcohol" in component A is reduced and the mass percentage of polyvinyl alcohol in component A is controlled at 3%, and the amount of water is increased accordingly. After adjustment, the composition is: polyvinyl alcohol PVA-1788 1%, polyvinyl alcohol BP-0599 2%, water 96.5%, defoamer 0.3%, and preservative 0.2%.

[0069] Comparative Example 4

[0070] The basic structure is the same as in Example 1, except that in component B, tartaric acid is replaced with citric acid of the same mass percentage.

[0071] Comparative Example 5

[0072] It is basically the same as Example 1, except that the entire component A is replaced with water.

[0073] Performance testing

[0074] 1. Performance tests were conducted on Examples 1-3 and Comparative Examples 1-5. The test methods followed the flowability index of standard JC / T985-2017 "Cement-based Self-leveling Mortar for Floors". The determination of the failure mode was based on the performance test methods in GB 18445-2012 "Cement-based Penetrating Crystalline Waterproofing Materials". The chalking was judged by lightly rubbing the coating with a finger after 2-3 days of drying and observing whether there was chalking or powdering. The water-locking performance was judged by testing the adhesion strength on the dry substrate after 7 days. Specific results are shown in Table 4.

[0075] Table 4

[0076]

[0077]

[0078] As can be seen from the above, the addition of acrylate resin to component A has a significant impact on secondary impermeability, hindering penetration and crystallization. The content of PVA not only has a significant impact on water-locking performance and impermeability, but also significantly affects self-leveling performance. Compared with Example 1, Comparative Example 5, when the entire component A was replaced with water, showed a sedimentation and stratification phenomenon.

[0079] 2. The waterproof coatings prepared in Example 1 with components A and B in ratios of 1:0.6, 1:0.8, and 1:1 were subjected to the following performance tests (dry environment preparation and curing). The specific results are shown in Table 5.

[0080] Table 5

[0081]

[0082]

[0083] As can be seen from the above, as the proportion of component B increases, the effect on self-leveling performance is relatively small, and the anti-permeability pressure ratio of the coating with penetrating crystallization is improved.

[0084] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0085] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A method for preparing a self-leveling, penetrating, crystalline waterproof coating, the waterproof coating comprising component A and component B, wherein component A contains water, characterized in that, The preparation method includes: Preparation of component A: By mass percentage, component A further comprises 10%-20% polyvinyl alcohol, and component A does not contain any other film-forming resins besides polyvinyl alcohol; the polyvinyl alcohol is composed of a first polyvinyl alcohol and a second polyvinyl alcohol, the mass ratio of the first polyvinyl alcohol to the second polyvinyl alcohol is 0.8-2:1, the degree of polymerization of the first polyvinyl alcohol is 1500-2000, and the degree of alcoholysis is 75%-95%; the degree of polymerization of the second polyvinyl alcohol is 500-800, and the degree of alcoholysis is 98%-100%; The components in component A are mixed evenly to obtain component A; Preparation of component B: Component B comprises cement, quartz sand, an active crystalline chemical substance, and tartaric acid. By mass percentage, component B comprises 30%-35% cement, 30%-50% quartz sand, 15%-35% active crystalline chemical substance, and 0.1%-0.8% tartaric acid. The active crystalline chemical substance is composed of 1000-1500 mesh metakaolin, 3500-4500 mesh metakaolin, and 600-1000 mesh silica fume, with a mass ratio of 2.5-3.5:0.6-1.2:1 for the 1000-1500 mesh metakaolin, 3500-4500 mesh metakaolin, and 600-1000 mesh silica fume. The components in component B are mixed evenly to obtain component B. In the waterproof coating, the mass ratio of component A to component B is 1:0.6-1.

2. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, In the preparation of component A, each component in component A is weighed according to the formula, added to a temperature-controlled stirring vessel, and stirred for 40-60 minutes at a water temperature of 85-95℃ and a stirrer at 600-1000 rpm.

3. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, By mass percentage, component A comprises 10%-20% polyvinyl alcohol, 78%-90% water, 0-1% defoamer, and 0-1% preservative.

4. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 3, characterized in that, By mass percentage, component A comprises 15%-20% polyvinyl alcohol, 78%-84% water, 0.05-1% defoamer, and 0.05-1% preservative.

5. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, In the preparation of component B, each component of component B is weighed according to the formula, and 40%-60% of cement, 40%-60% of quartz sand, and 40%-60% of metakaolin are added to a horizontal dry mortar mixer in sequence. Then, other components except cement, quartz sand, and metakaolin are added, and stirring is continued. Then, the remaining cement, remaining quartz sand, and remaining metakaolin are added and stirred until well mixed to obtain the final product.

6. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, Component B further comprises polycarboxylate superplasticizer and bentonite, wherein, by mass percentage, the polycarboxylate superplasticizer accounts for 0.1%-0.25% and the bentonite accounts for 0.05%-0.2%.

7. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, By mass percentage, component A contains 15%-20% polyvinyl alcohol; by mass percentage, component B contains 0.2%-0.6% tartaric acid.

8. The method for preparing the self-leveling penetrating crystallizing waterproof coating according to claim 1, characterized in that, When in use, component A and component B are mixed according to the formula ratio to obtain a self-leveling penetrating crystalline waterproof coating. After the self-leveling penetrating crystalline waterproof coating is applied to the concrete base to form a waterproof coating, the curing and leveling processes are omitted, and the waterproof membrane can be directly applied.

9. A self-leveling penetrating crystalline waterproof coating prepared by any one of claims 1-8; wherein the self-leveling penetrating crystalline waterproof coating achieves a water-locking performance of 1.2 MPa in a 7-day adhesion strength test on a dry substrate and does not powder.

Images