Super-strong anti-permeability polymer cement waterproof coating and preparation method thereof

Abstract

The invention discloses a super-strong anti-permeability polymer cement waterproof coating and a preparation method thereof, and belongs to the technical field of building waterproof materials. The coating is formed by mixing a liquid material and a powder material according to the mass ratio of 1: 1, the liquid material comprises distilled water, a defoaming agent, a coalescing agent, a dispersing agent and an acrylic emulsion, and the powder material comprises calcium carbonate, bentonite, silicon dioxide, cement and (3-mercaptopropyl) triethoxysilane functionalized acidified sepiolite. The sepiolite is subjected to acid activation and silane coupling agent functional modification, on the basis of maintaining the elongation at break of the coating to be 90% and the tensile strength to be 1.84 MPa, the anti-permeability performance of the material is remarkably improved, the anti-permeability pressure can be up to 0.81 MPa according to the actual test, and the coating has excellent application prospects.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to a super-strong impermeable polymer cement waterproof coating and its preparation method. Background Technology

[0002] In modern construction engineering, the quality of waterproofing directly affects the structural safety and service life of buildings. Polymer cement waterproofing coatings, with their excellent physical and mechanical properties, good substrate adaptability, and environmentally friendly construction characteristics, have become a core material for key waterproofing areas such as basements, roofs, kitchens, and bathrooms. Major infrastructure projects and underground spaces place even more stringent demands on the superior impermeability of waterproofing coatings.

[0003] However, existing polymer cement waterproof coatings still exhibit significant shortcomings in their anti-seepage reliability during long-term service. Microstructural analysis reveals that waterproof coatings consist of interwoven organic emulsion film-forming substances and inorganic hydration products. Due to the substantial surface energy difference between organic polymers and inorganic mineral powders, the interface between the two phases often suffers from weak bonding and poor compatibility. During the coating curing and drying process, these interface defects easily evolve into penetrating microcracks or capillary channels. Under sustained high water pressure, moisture physically penetrates along these weak interfaces and micropores, causing the coating to swell, delaminate, or even fail, ultimately leading to steel corrosion and deterioration of the concrete structure.

[0004] To improve this situation, the industry has generally tried to introduce active mineral fillers for reinforcement. Sepiolite, as a natural fibrous hydrous magnesium silicate mineral, has an extremely high specific surface area and a unique layered chain nanoporous structure, making it theoretically an ideal material for improving the density of coatings. However, due to the large number of acidic hydroxyl groups on the surface of natural sepiolite and its strong hydrophilicity, direct addition of it easily leads to agglomeration, making it difficult to form a uniform barrier network in the polymer matrix.

[0005] Therefore, how to precisely modify and activate the surface of sepiolite through chemical means, and construct a "bridging" system that can both deeply integrate with cement hydration products and form strong chemical bonds with polymer molecular chains, so as to completely block microscopic water seepage channels, has become a key research direction in the field of high-performance waterproof materials to break through the anti-seepage bottleneck and achieve long-term protection. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a super-strong impermeable polymer cement waterproof coating and its preparation method.

[0007] This invention is achieved through the following technical solution: A super-strong impermeable polymer cement waterproof coating is made by mixing liquid and powder in a mass ratio of 1:1. The liquid includes the following components in parts by weight: 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion. The powder includes the following components in parts by weight: 20 parts calcium carbonate 350 mesh, 0.8 parts bentonite, 20 parts silica 100 mesh, 35 parts cement, and 1-10 parts functionalized sepiolite.

[0008] Furthermore, the functionalized sepiolite is (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite.

[0009] Furthermore, the powder contains 8 parts by weight of (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite.

[0010] Further, the preparation method of the (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite includes the following steps: 1) Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, filter, wash the precipitate with deionized water until chloride ions are undetectable, and dry to obtain acid-activated sepiolite; 2) Add 6g of acid-activated sepiolite to 150mL of toluene, and stir for 30min under a nitrogen atmosphere; 3) Add 6mL of (3-mercaptopropyl)triethoxysilane dropwise to the system in step 2), and reflux for 24h; 4) After filtering the precipitate, wash with ethanol and dry under nitrogen to obtain the final product.

[0011] Furthermore, the functionalized sepiolite is (2-mercaptoethyl)trimethoxysilane-functionalized acidified sepiolite.

[0012] Further, the preparation method of the (2-mercaptoethyl)trimethoxysilane-functionalized acidified sepiolite includes the following steps: 1) Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, filter, wash the precipitate with deionized water until no chloride ions are detected, and dry to obtain acid-activated sepiolite; 2) Add 6g of acid-activated sepiolite to 150mL of toluene, and stir for 30min under a nitrogen atmosphere; 3) Add 6mL of (2-mercaptoethyl)trimethoxysilane dropwise to the system in step 2), and reflux for 24h; 4) After filtering the precipitate, wash with ethanol and dry under nitrogen to obtain the final product.

[0013] This invention also provides a method for preparing a super-strong impermeable polymer cement waterproof coating, comprising the following steps: 1) Preparing the liquid: adding acrylic emulsion to water, then adding film-forming aid, dispersant and defoamer, stirring for 30 minutes to obtain the liquid; 2) Preparing the powder: mixing cement, calcium carbonate, bentonite, silica and functionalized sepiolite in proportion, stirring for 30 minutes to obtain the powder; 3) Mixing: adding the liquid and powder in a 1:1 mass ratio to a mixer, stirring for 30 minutes to obtain the final product.

[0014] Furthermore, its elongation at break is 90%, its tensile strength is 1.84 MPa, and its impermeability is 0.70-0.81 MPa.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: This invention introduces a specific proportion of (3-mercaptopropyl)triethoxysilane to functionalize acidified sepiolite, significantly enhancing the system's density while maintaining excellent mechanical properties such as 90% elongation at break and 1.84 MPa tensile strength. This increases the impermeability pressure from 0.68 MPa in the base group to a maximum of 0.81 MPa. Through acid activation and silane functionalization modification, this method effectively improves the interfacial compatibility between inorganic fillers and organic emulsions, solving the problem of easy agglomeration of natural sepiolite. Without increasing the complexity of construction, it achieves a leapfrog improvement in the impermeability of the coating. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments. The illustrative embodiments and descriptions of this invention are only used to explain this invention and are not intended to limit this invention.

[0017] The preparation method of (3-mercaptopropyl)triethoxysilane (HS-(CH2)3-Si(OCH2CH3)3)-functionalized acidified sepiolite in this invention is as follows: Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, then filter, wash the precipitate with deionized water until no chloride ions are detected; dry for later use to obtain acid-activated sepiolite. Take 6g of acid-activated sepiolite and 6mL of mercaptosilane, add them to 150mL of toluene, stir for 30min under a nitrogen atmosphere, then add 6mL of (3-mercaptopropyl)triethoxysilane dropwise, reflux for 24h, filter the precipitate, wash the precipitate with ethanol, and then dry it under nitrogen to obtain the final product.

[0018] The preparation method of (2-mercaptoethyl)trimethoxysilane (HS-(CH2)2-Si(OCH3)3)-functionalized acidified sepiolite in this invention is as follows: Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, then filter, wash the precipitate with deionized water until no chloride ions are detected; dry for later use to obtain acid-activated sepiolite. Take 6g of acid-activated sepiolite and 6mL of mercaptosilane, add them to 150mL of toluene, stir for 30min under a nitrogen atmosphere, then add 6mL of (2-mercaptoethyl)trimethoxysilane dropwise, reflux for 24h, filter the precipitate, wash the precipitate with ethanol, and then dry it under nitrogen to obtain the final product.

[0019] The preparation method of (3-mercaptopropyl)triethoxysilane (HS-(CH2)3-Si(OCH2CH3)3)-functionalized natural sepiolite in this invention is as follows: Take 6g of natural sepiolite and 6mL of mercaptosilane, add them to 150mL of toluene, stir for 30min under a nitrogen atmosphere, then add 6mL of (3-mercaptopropyl)triethoxysilane dropwise, reflux for 24h, filter the precipitate, wash the precipitate with ethanol, and then dry it under nitrogen to obtain the final product.

[0020] Example 1 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder materials include: 20 parts calcium carbonate (350 mesh), 0.8 parts bentonite, 20 parts silica (100 mesh), 35 parts cement, and 1 part (3-mercaptopropyl)triethoxysilane HS-(CH2)3-Si(OCH2CH3)3) functionalized acidified sepiolite.

[0021] The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0022] Example 2 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 4 parts of (3-mercaptopropyl)triethoxysilane HS-(CH2)3-Si(OCH2CH3)3) functionalized acidified sepiolite; The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0023] Example 3 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 6 parts of (3-mercaptopropyl)triethoxysilane HS-(CH2)3-Si(OCH2CH3)3) functionalized acidified sepiolite; The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0024] Example 4 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 8 parts of (3-mercaptopropyl)triethoxysilane HS-(CH2)3-Si(OCH2CH3)3) functionalized acidified sepiolite; The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0025] Example 5 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 10 parts of (3-mercaptopropyl)triethoxysilane HS-(CH2)3-Si(OCH2CH3)3) functionalized acidified sepiolite; The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0026] Comparative Example 1 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 8 parts of (2-mercaptoethyl)trimethoxysilane-functionalized acidified sepiolite. The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized acidified sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0027] Comparative Example 2 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder includes 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 8 parts of (3-mercaptoethyl)trimethoxysilane-functionalized natural sepiolite. The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and functionalized sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0028] Comparative Example 3 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder consists of 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 8 parts of natural sepiolite. The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and natural sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0029] Comparative Example 4 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder materials include 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, 35 parts of cement, and 8 parts of acidified sepiolite. The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid; mix cement, calcium carbonate, bentonite, silica and sepiolite evenly, stir for 30 minutes to obtain powder; add liquid and powder to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0030] The preparation method of acid-activated sepiolite is as follows: 10g of natural sepiolite is added to 100mL of 4MHCl, stirred at room temperature for 10h, then filtered, and the precipitate is washed with deionized water until no chloride ions are detected; dried for later use, and acid-activated sepiolite is obtained.

[0031] Comparative Example 5 A super-strong impermeable polymer cement waterproof coating, the liquid component of which includes 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; Its powder consists of 20 parts of 350-mesh calcium carbonate, 0.8 parts of bentonite, 20 parts of 100-mesh silica, and 35 parts of cement. The preparation method of the super-strong impermeable polymer cement waterproof coating is as follows: add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid material; mix cement, calcium carbonate, bentonite and silica evenly, stir for 30 minutes to obtain powder material; add liquid material and powder material to a mixer at a mass ratio of 1:1, stir for 30 minutes to obtain the final product.

[0032] Test case The mechanical properties and impermeability of the coatings were tested in accordance with standards GB / T23445-2009 and GB / T16777-2008.

[0033] Table 1 Performance Tests

[0034] As can be seen from the performance test data in Table 1, in all 10 experimental samples, the two mechanical indicators, elongation at break and tensile strength, showed extremely high numerical stability, with the measured values ​​remaining constant at 90% and 1.84 MPa, respectively, without fluctuations due to formula adjustments. However, the impermeability index showed a significant numerical gradient due to the differences in the composition and content of each component. Specifically, in Examples 1 to 5, with the increase of the amount of (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite added, the impermeability pressure steadily increased from 0.70 MPa to a peak of 0.81 MPa. This value was significantly better than the data of each group that only changed the type of silane coupling agent, omitted the acid activation step, used natural sepiolite, or used only acidified sepiolite. Moreover, it was significantly improved compared to Comparative Example 5, which did not add any sepiolite component. This fully demonstrates the decisive influence of specific functionalized modified components on the impermeability numerical dimension of the coating.

Claims

1. A polymer cement waterproof coating with superior impermeability, characterized in that, It is composed of liquid and powder mixed in a mass ratio of 1:1; the liquid includes the following components in parts by weight: 4 parts distilled water, 0.1 parts defoamer XHD103, 0.8 parts film-forming aid alcohol ester-12, 0.4 parts dispersant DS-172, and 50 parts acrylic emulsion; the powder includes the following components in parts by weight: 20 parts calcium carbonate 350 mesh, 0.8 parts bentonite, 20 parts silica 100 mesh, 35 parts cement, and 1-10 parts functionalized sepiolite.

2. The super-strong impermeable polymer cement waterproof coating according to claim 1, characterized in that, The functionalized sepiolite is (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite.

3. The super-strong impermeable polymer cement waterproof coating according to claim 2, characterized in that, The powder contains 8 parts by weight of (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite.

4. The super-strong impermeable polymer cement waterproof coating according to claim 2, characterized in that, The preparation method of (3-mercaptopropyl)triethoxysilane-functionalized acidified sepiolite includes the following steps: 1) Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, filter, wash the precipitate with deionized water until chloride ions are undetectable, and dry to obtain acid-activated sepiolite; 2) Add 6g of acid-activated sepiolite to 150mL of toluene, and stir for 30min under a nitrogen atmosphere; 3) Add 6mL of (3-mercaptopropyl)triethoxysilane dropwise to the system in step 2), and reflux for 24h; 4) After filtering the precipitate, wash with ethanol and dry under nitrogen to obtain the final product.

5. The super-strong impermeable polymer cement waterproof coating according to claim 1, characterized in that, The functionalized sepiolite is (2-mercaptoethyl)trimethoxysilane-functionalized acidified sepiolite.

6. The super-strong impermeable polymer cement waterproof coating according to claim 5, characterized in that, The preparation method of (2-mercaptoethyl)trimethoxysilane-functionalized acidified sepiolite includes the following steps: 1) Add 10g of natural sepiolite to 100mL of 4MHCl, stir at room temperature for 10h, filter, wash the precipitate with deionized water until chloride ions are undetectable, and dry to obtain acid-activated sepiolite; 2) Add 6g of acid-activated sepiolite to 150mL of toluene, and stir for 30min under a nitrogen atmosphere; 3) Add 6mL of (2-mercaptoethyl)trimethoxysilane dropwise to the system in step 2), and reflux for 24h; 4) After filtering the precipitate, wash with ethanol and dry under nitrogen to obtain the final product.

7. The method for preparing a super-strong impermeable polymer cement waterproof coating according to claim 1, characterized in that, Includes the following steps: 1) Preparation of liquid material: Add acrylic emulsion to water, then add film-forming aid, dispersant and defoamer, stir for 30 minutes to obtain liquid material; 2) Preparation of powder material: Mix cement, calcium carbonate, bentonite, silica and functionalized sepiolite in proportion and stir for 30 minutes to obtain powder material; 3) Mixing: Add liquid material and powder material to a mixer at a mass ratio of 1:1 and stir for 30 minutes to obtain the final product.

8. The super-strong impermeable polymer cement waterproof coating according to claim 1, characterized in that, Its elongation at break is 90%, its tensile strength is 1.84 MPa, and its impermeability is 0.70-0.81 MPa.

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