One-component highly water-resistant styrene acrylic emulsion waterproof coating and preparation method thereof

Abstract

The present invention belongs to the technical field of waterproof coatings and discloses a one-component, highly water-resistant styrene-acrylic emulsion waterproof coating and its preparation method. The one-component, highly water-resistant styrene-acrylic emulsion waterproof coating comprises the following raw materials by weight: 100 parts styrene-acrylic emulsion, 1-5 parts tetrafluoroterephthalic alcohol, 1-3 parts dispersant, 2-5 parts defoamer, 1-3 parts thickener, 5-6 parts methanol, 0-1 part pH adjuster, 2-6 parts water, and 90-110 parts ground calcium carbonate. The present invention adds tetrafluoroterephthalic alcohol, which undergoes an esterification reaction with the styrene-acrylic resin to form a stable cross-linked structure and introduces hydrophobic fluorine atoms, thereby improving the mechanical properties and water resistance of the styrene-acrylic emulsion waterproof coating.

Description

Technical Field

[0001] The invention belongs to the technical field of waterproof coatings, and particularly relates to a single-component highly water-resistant styrene-acrylic emulsion waterproof coating and a preparation method thereof. Background Art

[0002] One-component styrene acrylic emulsion waterproof coatings are based on a multi-component copolymer emulsion of styrene, acrylates, and other materials, supplemented with various fillers and emulsion additives. A viscous liquid that flows at room temperature, it can be evenly applied to building surfaces. It is particularly suitable for application on detailed structures such as facades, protrusions, and narrow spaces. After curing, it forms a complete waterproof film on these complex surfaces, achieving a waterproof and anti-seepage effect.

[0003] One-component styrene acrylic emulsion waterproof coatings offer strong adhesion and excellent elastic-plastic properties. The coating forms a seamless waterproof system on the substrate surface, adapting to structural deformation. However, these coatings suffer from poor water resistance. This means that their mechanical and waterproof properties degrade significantly after prolonged immersion in water. This significantly limits their application in environments subject to long-term water immersion, such as underground projects, swimming pools, and reservoirs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the deficiencies in the prior art and provide a one-component highly water-resistant styrene acrylic emulsion waterproof coating and a preparation method thereof. By adding tetrafluoroterephthalate, while undergoing an esterification reaction with a styrene acrylic resin to form a stable cross-linked structure, hydrophobic fluorine atoms are introduced, thereby improving the mechanical properties and water resistance of the styrene acrylic emulsion waterproof coating.

[0005] In order to solve the technical problem proposed by the present invention, the present invention provides a one-component highly water-resistant styrene acrylic emulsion waterproof coating, comprising the following raw materials in parts by mass: 100 parts of styrene acrylic emulsion, 1-5 parts of tetrafluoroterephthalic alcohol, 1-3 parts of a dispersant, 2-5 parts of a defoaming agent, 1-3 parts of a thickener, 5-6 parts of methanol, 0-1 part of a pH regulator, 2-6 parts of water, and 90-110 parts of heavy calcium carbonate.

[0006] In the above scheme, the styrene acrylic emulsion is a styrene-acrylate emulsion with a solid content of 50-60%.

[0007] In the above solution, the dispersant is a polycarboxylate sodium salt dispersant.

[0008] In the above solution, the defoaming agent is an organosilicon defoaming agent.

[0009] In the above solution, the thickener is a cellulose thickener.

[0010] In the above solution, the pH regulator is aqueous ammonia with a concentration of 25-28 wt%.

[0011] In the above solution, the particle size of the heavy calcium carbonate is 200 to 300 meshes.

[0012] The present invention also provides a method for preparing a one-component highly water-resistant styrene acrylic emulsion waterproof coating, which specifically comprises the following steps:

[0013] 1) stirring and mixing water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol to obtain a mixture A;

[0014] 2) adding styrene acrylic emulsion and pH regulator to mixture A, stirring to obtain mixture B;

[0015] 3) adding heavy calcium carbonate to mixture B and stirring to obtain mixture C;

[0016] 4) adding a defoamer to the mixture C, stirring and then standing to defoam, to obtain a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

[0017] In the above scheme, in step 1), the stirring rate is 1000-1500 r / min, and the stirring time is 10-15 min.

[0018] In the above scheme, in step 2), the stirring rate is 1500-2000 r / min, and the stirring time is 10-15 min.

[0019] In the above scheme, in step 3), the stirring rate is 1000-1500 r / min, and the stirring time is 10-15 min.

[0020] In the above scheme, in step 4), the stirring rate is 300-500 r / min, and the stirring time is 5-10 min.

[0021] In the above scheme, the temperature during the entire preparation process is 20-30°C.

[0022] In the above solution, the purpose of the pH regulator is to adjust the pH of the mixture B to 7-9.

[0023] In the above solution, the one-component highly water-resistant styrene acrylic emulsion waterproof coating is used within 1 hour after preparation.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1) The present invention uses tetrafluoroterephthalic acid as a modifier. The modifier contains highly reactive hydroxymethyl groups, which can undergo esterification reaction with the carboxyl groups in the styrene acrylic resin to form a stable cross-linked structure, thereby improving the mechanical properties of the coating. The fluorine atoms contained in the modifier are highly hydrophobic and can form a hydrophobic barrier on the surface of the coating, thereby reducing the water absorption rate of the coating and significantly improving the water resistance of the coating. Therefore, the mechanical properties and water resistance of the styrene acrylic emulsion waterproof coating are simultaneously improved.

[0026] 2) In the system of the present invention, methanol can better disperse tetrafluoroterephthalate dimethanol in the emulsion, strengthen the reaction between tetrafluoroterephthalate dimethanol and styrene acrylic resin, and promote the modification effect of tetrafluoroterephthalate dimethanol on styrene acrylic emulsion. DETAILED DESCRIPTION

[0027] In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.

[0028] In the following examples, the dispersant used is sodium polycarboxylate dispersant HY-731A, the defoaming agent is silicone defoaming agent TH-5800, the thickener is carboxymethyl cellulose, the pH regulator is 27 wt% ammonia water, and the particle size of the heavy calcium carbonate is 200 mesh.

[0029] Example 1

[0030] A one-component highly water-resistant styrene acrylic emulsion waterproof coating comprises the following raw materials in parts by mass: 100 parts of styrene acrylic emulsion with a solid content of 56%, 3 parts of tetrafluoroterephthalic alcohol, 1 part of a dispersant, 2 parts of a defoaming agent, 1 part of a thickener, 5 parts of methanol, 1 part of a pH regulator, 4 parts of water, and 100 parts of heavy calcium carbonate.

[0031] The preparation method comprises the following steps:

[0032] 1) stirring water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol for 13 minutes at a temperature of 25° C. and a stirring rate of 1300 r / min to obtain a mixture A;

[0033] 2) Adding styrene-acrylic emulsion and pH adjuster to mixture A, stirring for 15 minutes at 25° C. and 1800 rpm to obtain mixture B having a pH of 7 to 9;

[0034] 3) adding heavy calcium carbonate to mixture B, stirring for 13 min at a temperature of 25° C. and a stirring rate of 1300 rpm to obtain mixture C;

[0035] 4) Add a defoamer to the mixture C, stir for 8 minutes at a temperature of 25° C. and a stirring rate of 400 r / min, and allow to stand for defoaming to obtain a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

[0036] Example 2

[0037] A one-component highly water-resistant styrene acrylic emulsion waterproof coating comprises the following raw materials in parts by mass: 100 parts of styrene acrylic emulsion with a solid content of 53%, 1 part of tetrafluoroterephthalic alcohol, 2 parts of a dispersant, 3 parts of a defoaming agent, 2 parts of a thickener, 5 parts of methanol, 0 parts of a pH regulator, 2 parts of water, and 90 parts of heavy calcium carbonate.

[0038] The preparation method comprises the following steps:

[0039] 1) Mixing water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol at 20° C. and a stirring rate of 1000 rpm for 10 minutes to obtain a mixture A;

[0040] 2) Adding styrene acrylic emulsion and pH adjuster to mixture A, stirring for 10 min at 20° C. and 1500 rpm to obtain mixture B with a pH of 7 to 9;

[0041] 3) adding heavy calcium carbonate to mixture B, stirring for 10 min at a temperature of 20° C. and a stirring rate of 1000 rpm to obtain mixture C;

[0042] 4) Add a defoamer to the mixture C, stir for 5 minutes at a temperature of 20° C. and a stirring rate of 300 r / min, and allow to stand for defoaming to obtain a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

[0043] Example 3

[0044] A one-component highly water-resistant styrene acrylic emulsion waterproof coating comprises the following raw materials in parts by mass: 100 parts of styrene acrylic emulsion with a solid content of 58%, 5 parts of tetrafluoroterephthalic alcohol, 3 parts of a dispersant, 3 parts of a defoaming agent, 3 parts of a thickener, 6 parts of methanol, 1 part of a pH regulator, 6 parts of water, and 110 parts of heavy calcium carbonate.

[0045] The preparation method comprises the following steps:

[0046] 1) Mixing water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol at 30° C. and a stirring rate of 1500 rpm for 15 minutes to obtain a mixture A;

[0047] 2) Adding styrene acrylic emulsion and pH adjuster to mixture A, stirring at 30°C and 2000 rpm for 15 min to obtain mixture B with a pH of 7 to 9;

[0048] 3) adding heavy calcium carbonate to mixture B, stirring for 15 min at a temperature of 30° C. and a stirring rate of 1400 rpm to obtain mixture C;

[0049] 4) Add a defoamer to the mixture C, stir for 10 min at a temperature of 30° C. and a stirring rate of 500 r / min, and allow to stand for defoaming to obtain a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

[0050] Comparative Example 1-1

[0051] The only difference between Comparative Example 1-1 and Example 1 is that no methanol is added.

[0052] Comparative Example 1-2

[0053] The only difference between Comparative Example 1-2 and Example 1 is that tetrafluorophenylenediol is not added.

[0054] Comparative Example 2

[0055] The only difference between Comparative Example 2 and Example 2 is that methanol and tetrafluorophenylenediol are not added.

[0056] Comparative Example 3

[0057] The only difference between Comparative Example 3 and Example 3 is that methanol and tetrafluorophenylenediol are not added.

[0058] The styrene acrylic emulsion waterproof coatings prepared in each embodiment and each comparative example were respectively coated and sampled according to JC / T 864-2008 "Polymer Emulsion Building Waterproof Coatings". The water absorption rate of the coatings and the tensile strength and elongation of the coatings before and after immersion in water for 7 days were tested. The contact angle of the coatings was also tested using a CA200 fully automatic contact angle meter. The test results are shown in Table 1.

[0059] Table 1 Performance test results

[0060]

[0061]

[0062] From the data of Example 1 and Comparative Example 1-1 and Comparative Example 1-2, it can be seen that the coating of Example 1, in which tetrafluoro-p-terephthalic alcohol and methanol are added at the same time, has the best water resistance and mechanical properties, while the water resistance and mechanical properties of Comparative Example 1-2, in which tetrafluoro-p-terephthalic alcohol is not added, are significantly reduced. This is because tetrafluoro-p-terephthalic alcohol contains highly reactive hydroxymethyl groups, which can undergo esterification reaction with the carboxyl groups in the styrene-acrylic resin to form a stable cross-linked structure, thereby improving the mechanical properties of the coating. At the same time, the fluorine atoms therein are highly hydrophobic and can form a hydrophobic barrier on the coating surface, reducing the water absorption rate of the coating and significantly improving the water resistance of the coating. The water resistance and mechanical properties of Comparative Example 1-1 without adding methanol are significantly improved compared with Comparative Example 1-2, but there is still a large difference from Example 1. This is because methanol can strengthen the reaction between tetrafluoro-p-terephthalic alcohol and styrene-acrylic resin. The synergistic use of tetrafluoro-p-terephthalic alcohol and methanol enhances the reaction and effect. The data of Example 2 and Comparative Example 2, and Example 3 and Comparative Example 3 can further verify the effect of tetrafluoro-p-terephthalic alcohol and methanol when used.

[0063] The above embodiments are merely examples for clarification and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications may be made based on the above descriptions. It is not necessary and impossible to enumerate all implementation methods here, and any obvious variations or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A one-component highly water-resistant styrene acrylic emulsion waterproof coating, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of styrene-acrylic emulsion, 1-5 parts of tetrafluoroterephthalic alcohol, 1-3 parts of dispersant, 2-5 parts of defoaming agent, 1-3 parts of thickener, 5-6 parts of methanol, 0-1 part of pH regulator, 2-6 parts of water, and 90-110 parts of heavy calcium carbonate; The preparation method of the one-component highly water-resistant styrene acrylic emulsion waterproof coating comprises the following steps: 1) Stirring and mixing water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol to obtain a mixture A; 2) Adding styrene acrylic emulsion and pH adjuster to mixture A, stirring to obtain mixture B; 3) Adding heavy calcium carbonate to mixture B and stirring to obtain mixture C; 4) Add a defoamer to the mixture C, stir it, and let it stand to defoam, thereby obtaining a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

2. The one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 1, characterized in that: The styrene acrylic emulsion is a styrene-acrylate emulsion with a solid content of 50-60%.

3. The one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 1, characterized in that: The pH regulator is ammonia water with a concentration of 25~28 wt%.

4. The one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 1, characterized in that: The dispersant is a polycarboxylate sodium salt dispersant; the defoaming agent is an organosilicon defoaming agent; and the thickener is a cellulose thickener.

5. The one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 1, characterized in that: The particle size of the heavy calcium carbonate is 200-300 meshes.

6. The method for preparing the one-component highly water-resistant styrene acrylic emulsion waterproof coating according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) Stirring and mixing water, methanol, a dispersant, a thickener, and tetrafluoroterephthalic alcohol to obtain a mixture A; 2) Adding styrene acrylic emulsion and pH adjuster to mixture A, stirring to obtain mixture B; 3) Adding heavy calcium carbonate to mixture B and stirring to obtain mixture C; 4) Add a defoamer to the mixture C, stir it, and let it stand to defoam, thereby obtaining a one-component highly water-resistant styrene acrylic emulsion waterproof coating.

7. The method for preparing the one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 6, wherein: The stirring rate in step 1) and step 3) is 1000-1500 r / min, and the stirring time is 10-15 min.

8. The method for preparing the one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 6, wherein: The stirring rate in step 2) is 1500~2000 r / min, and the stirring time is 10~15 min; the stirring rate in step 4) is 300~500 r / min, and the stirring time is 5~10 min.

9. The method for preparing a one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 6, characterized in that: The temperature during the preparation process is 20~30℃.

10. The method for preparing a one-component highly water-resistant styrene acrylic emulsion waterproof coating according to claim 6, characterized in that: The pH regulator adjusts the pH of the mixture B to 7-9.

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