Waterproof material for house repair and preparation method thereof

Abstract

The invention discloses a waterproof material for house repair and a preparation method thereof, and relates to the technical field of house repair and waterproofing. The waterproof material provided by the invention is composed of an organic silicon modified asphalt matrix, a core-shell particle moisture absorption and heat release unit with lithium chloride loaded on MIL-101 (Cr), an aluminum powder-sodium hydroxide temperature control type microcapsule curing trigger unit and a surface silanization straw nano-fibril reinforced net. The preparation method comprises the following steps: melting modified asphalt, dispersing, curing and triggering microcapsules, adding moisture-absorbing and heat-releasing core-shell particles at 80 DEG C, finally dip-coating a fiber-reinforced net, and carrying out gradient cooling to form sheets; during use, only the sheet needs to be attached to a leakage base surface; environmental moisture triggers LiCl to absorb moisture and Al / NaOH to react to release heat, so that asphalt-siloxane is promoted to be crosslinked and deeply permeate into a basal plane, dehumidification is not needed, and self-curing is realized within 48 hours; compared with the existing modified asphalt coiled material, light-cured resin and nano permeable material, the modified asphalt coiled material disclosed by the invention has high wet surface adhesion and back water pressure impermeability at the same time; and long-term self-adaption to 3mm static and dynamic cracks is maintained.

Description

Technical Field

[0001] This invention relates to the field of building repair and waterproofing technology, and in particular to a waterproofing material for building repair and its preparation method. Background Technology

[0002] The basement's back side leaks due to prolonged exposure to extreme environments characterized by high humidity, lack of sunlight, and active structural deformation. The walls are continuously permeated by groundwater pressure and soil moisture, often reaching saturation levels, and the base surface becomes loose due to concrete carbonization.

[0003] Current mainstream solutions rely on modified bitumen membranes or UV-cured resins, but the former's adhesion to damp substrates decreases by more than 50%, while the latter cannot cure at all due to the lack of ultraviolet light. During construction, additional dehumidification equipment is often required, which increases costs and makes it difficult to completely eliminate repeated leaks.

[0004] Recent attempts at nano-permeable crystalline materials and water-swellable polyurethane have partially improved adaptability to humid environments, but they still have fatal flaws. Nanomaterials are sensitive to the width of cracks in the substrate, and fail when the crack exceeds 0.5mm; expanded polyurethane foams out of control in high humidity environments, forming hollow areas that lead to secondary peeling; more troublesome is that these materials lack sustained waterproofing ability after curing. Repair industry reports show that the average re-leakage rate of such repairs is as high as 65% within 2 years, and frequent repairs will further damage the building structure; therefore, there is an urgent need for a waterproof material for building repairs to solve these problems. Summary of the Invention

[0005] In view of the aforementioned existing problems, the present invention is proposed.

[0006] This invention provides a waterproof material for house repair and its preparation method to solve the problem of waterproof materials failing to cure independently and repeatedly leaking on the back surface of basements under conditions of high RH≥95% and structural deformation.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, embodiments of the present invention provide a waterproof material for house repair, comprising, Organosilicon-modified asphalt matrix; The moisture-absorbing and heat-releasing unit is composed of core-shell particles formed by lithium chloride supported on a metal-organic framework material; The curing trigger unit contains temperature-controlled microcapsules of aluminum powder and sodium hydroxide; Plant fiber reinforced netting, the plant fiber used is straw nanofibers with surface silanization treatment.

[0008] As a preferred embodiment of the waterproof material for house repair described in this invention, the temperature-controlled microcapsule has a wall made of polyurea-formaldehyde resin with a wall thickness of 0.1-0.3 μm, and the mass ratio of the core aluminum powder to sodium hydroxide is 1:0.8-1.2.

[0009] As a preferred embodiment of the waterproof material for house repair described in this invention, the metal-organic framework material in the core-shell particles is MIL-101(Cr), and the lithium chloride loading is 35-40% of the total particle weight.

[0010] As a preferred embodiment of the waterproof material for house repair described in this invention, the plant fiber reinforced mesh has a filament diameter of 20-50 nm, a mesh density of 100-120 mesh, and uses γ-aminopropyltriethoxysilane for silanization treatment.

[0011] Secondly, the present invention provides a method for preparing a waterproof material for house repair, comprising, Step S1: Heat the silicone-modified asphalt to 160-170℃ to melt it; Step S2: Add temperature-controlled microcapsules and stir at 800-1000 rpm for 10 minutes; Step S3: After cooling to 80°C, add the core-shell particles and stir at 300 rpm until evenly dispersed; Step S4: The mixture is coated onto the surface of the plant fiber reinforced mesh and cooled to form a sheet.

[0012] In a preferred embodiment of the preparation method of the waterproof material for house repair described in this invention, the stirring process in step S2 is carried out under nitrogen protection, and the temperature fluctuation range is ≤ ±2℃.

[0013] In a preferred embodiment of the preparation method of the waterproof material for house repair described in this invention, the coating thickness in step S4 is 1.5-2.0 mm, and the cooling adopts a gradient cooling method: 100℃→60℃→25℃. Cooling is performed from 100℃ to 60℃ at a rate of 5℃ / min, and water cooling is used from 60℃ to 25℃.

[0014] Thirdly, the present invention provides a method for using a waterproof material for house repair, comprising, After the sheet is attached to the leaking substrate, the core-shell particles absorb moisture through the ambient humidity. The released heat causes the temperature-controlled microcapsule wall to rupture, and sodium hydroxide catalyzes the cross-linking and penetration of the asphalt.

[0015] As a preferred embodiment of the method of using the waterproof material for house repair described in this invention, the method involves: after removing dust, spraying magnesium phosphate cement slurry and allowing it to stand for 2-3 minutes to form a needle-like crystalline layer.

[0016] Fourthly, this invention provides an application of a waterproof material for house repair in a damp environment on the back side of a basement. When the relative humidity of the construction environment is ≥95%, the material completes self-curing within 48 hours.

[0017] The beneficial effects of this invention are as follows: This invention relies on the dual triggering of the hygroscopic and exothermic reactions of LiCl@MIL-101 and Al / NaOH, achieving cross-linking and curing within 48 hours in an environment with RH ≥ 95%, without the need for dehumidification or heating equipment; the organosilicon-asphalt-silane cross-linked network endows the material with a wet surface peel strength > 1 MPa against saturated concrete, while simultaneously withstanding a continuous backwater pressure ≥ 0.6 MPa without leakage; the sheet material exhibits overall flexibility, and the straw nanofiber reinforcement mesh increases the crack following elongation to > 700%, enabling bridging of single-pass thicknesses of 3 mm and cyclic thicknesses of 0.4 mm or more. The structure shifts without cracking; the asphalt matrix forms bulk cross-links under NaOH catalysis; LiCl is repeatedly hygroscopic and dehumidified but still confined by MOF, preventing salt migration; after 96 dry-wet cycles, the permeability deterioration is less than 5%; this invention is solvent-free and flameless throughout the process; plant fibers utilize agricultural waste, significantly reducing carbon emissions compared to modified asphalt roll solutions; dehumidifiers and secondary repairs are eliminated, significantly reducing overall costs; in addition, this invention offers various forms such as sheet materials, self-spraying, and composite sealing, adaptable to narrow foundation pits, sidewalls, and irregular nodes, allowing for application by a single person, effectively shortening the construction period. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic flowchart of the method for preparing waterproof material for house repair in Example 1. Detailed Implementation

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0023] Example 1, referring to Figure 1 This is the first embodiment of the present invention, which provides a standard backwater sheet and preparation steps, the composition of which is shown in Table 1;

[0024] The matrix consists of organosilicon-modified asphalt, LiCl@MIL-101(Cr) as the hygroscopic and exothermic unit, Al / NaOH temperature-controlled microcapsules as the curing trigger unit, and γ-aminopropyltriethoxysilane-modified straw nanofiber mesh as the reinforcing skeleton. The preparation steps include: Surface preparation: Spray magnesium phosphate cement slurry (0.5mm thick) and let stand for 2.5-3 minutes; Step S1, Melting and Dispersion: Take 100 kg of organosilicon-modified asphalt, and in... Under protection ( Heat (<0.5 vol%) to 165 °C and hold at that temperature for 10 min.

[0025] Step S2, Add microcapsules: In Under protection ( <0.5 vol%), high shear at 800 rpm for 10 min. Material temperature fluctuation ≤ ±1.5℃.

[0026] Step S3, Add LiCl@MOF: Add in batches, stir at 300 rpm for 15 min, particle size... Control it within 4.0-4.5µm.

[0027] Step S4, dip coating: The material is cooled to 80°C and coated on both sides of the fiber web with a 1.8mm thick metering scraper; gradient cooling process: 100°C hot air zone (2min) → 60°C roller pressing zone (pressure 0.5MPa, cooling rate 5°C / min) → 25°C water cooling zone (cooling water flow rate 10L / min) to obtain a 2mm thick sheet.

[0028] The finished product was subjected to performance testing at (48h, 25℃, RH98%): Self-curing time: 32h (penetration ≤0.1mm); Wet peel strength: 1.24 MPa; According to GB 23445-2019 testing, the hydrostatic pressure is 0.6 MPa, and there is no leakage after 72 hours; A 3mm trapezoidal crack was simulated according to the JC / T 1067-2008 method, and the crack width was <0.1mm after 200,000 cycles.

[0029] The comparison results with commercially available products are shown in Table 2.

[0030] Comparative Example 1, unlike Example 1, did not contain LiCl@MIL-101(Cr); did not cure after 72 hours at 98%RH.

[0031] Comparative Example 2 differs from Example 1 in that it uses ordinary polyester mesh fabric; the wet peel strength is 0.31 MPa. Other preparation conditions not specifically described in this specification are the same as in Example 1 and will not be repeated here.

[0032] Testing Standard: GB / T 23445-2019 "Waterproof Coatings for Buildings" Example 2 is the second embodiment of the present invention, which provides a highly flexible and crack-resistant formulation: In Example 1, 6 wt% thermoplastic elastomer SBS particles were added to the matrix at 165°C and dispersed at 1200 rpm for 10 min under high shear. Continue cooling to 85℃, add 1wt% water-based epoxy toughening agent, stir at 400rpm for 5min, and keep the other steps unchanged.

[0033] Performance tests showed that the tensile elongation at break increased from 400% to 730%. Permeation increment after impact at -25℃ is <0.05g.

[0034] It is suitable for the backwater surface of underground continuous walls that are greatly affected by pit heave and shear displacement.

[0035] Example 3 is the third embodiment of the present invention, which provides a rapid cold-applied spray coating type: Step S1 was changed to emulsified organosilicon pitch (60% solids content) and 0.3wt% hydrophobic stabilizer (octadecyltrimethoxysilane) was added. A nano-silica hydrophobic layer (contact angle > 150°) was sprayed on the surface of the microcapsules. The particle size of LiCl@MOF was reduced to 1µm to prevent nozzle clogging, and the final coating thickness was 1.0mm.

[0036] At 25℃ and 95% RH, it takes 6 hours to surface dry and 24 hours to fully dry. The wet surface adhesion strength by pull-out method is ≥0.85 MPa. Suitable for on-site spraying without open flame in narrow areas with side walls.

[0037] According to GB 23445-2019, a backwater pressure of 0.4 MPa was tested for 48 hours, and no leakage was found.

[0038] Conduct spraying process verification: Continuous spraying for 30 minutes using a spray gun with an orifice diameter of 0.8 mm (working pressure 0.5 MPa): Nozzle clogging incidents: 0; Film thickness uniformity deviation: ±0.1mm; Microcapsule rupture rate: ≤2% (microscopic counting method).

[0039] Example 4 is the fourth embodiment of the present invention, which provides an enhanced durability composite system: Using the sheet material from Example 1 as the main layer, before construction, after removing the floating dust, spray magnesium phosphate cement slurry, let it stand for 2-3 minutes to form a needle-like crystalline layer, and then roll a 20µm polyurea protective layer on the surface (cured for 5 seconds).

[0040] A 28-day mold test was conducted according to ISO 846:2018, and the rating was 0 (no growth). After 400 hours of dry-wet cycling according to GB / T 23987-2009, the peel strength retention rate was 92% ± 3%. It improves the water vapor barrier efficiency by 38%, further inhibiting LiCl migration.

[0041] Table 3 compares the composite system with the single-layer system.

[0042] Note: Single system refers to the sheet of Example 1 without a polyurea protective coating; In summary, the waterproof material provided by this invention consists of an organosilicon-modified asphalt matrix, a core-shell particle moisture-absorbing and heat-releasing unit with lithium chloride loaded with MIL-101(Cr), an aluminum powder-sodium hydroxide temperature-controlled microcapsule curing triggering unit, and a surface-silanized straw nanofiber reinforcing mesh. The material is prepared by first melting the modified asphalt, dispersing and curing the triggering microcapsules, then adding the moisture-absorbing and heat-releasing core-shell particles at 80°C, and finally impregnating the fiber-reinforced mesh and gradient cooling to form a sheet. In use, the sheet is simply adhered to the leaking surface. Ambient moisture triggers LiCl moisture absorption and Al… The reaction with NaOH is exothermic, which in turn promotes the cross-linking of asphalt and siloxane and deep penetration into the substrate, achieving self-curing within 48 hours without dehumidification. Compared with existing modified asphalt rolls, UV-cured resins, and nano-penetrating materials, this invention has both high adhesion on wet surfaces and strong backwater pressure resistance. It maintains long-term adaptability to 3mm static and dynamic cracks. It can still cure in one go in an environment with RH≥95%, significantly reducing the re-leakage rate. This material is suitable for waterproofing and repairing backwater surfaces in long-term damp and structurally active environments such as basements, subway tunnel sections, and tunnel linings.

[0043] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A waterproof material for house repair, characterized in that, include, Organosilicon-modified asphalt matrix; The moisture-absorbing and heat-releasing unit is composed of core-shell particles formed by lithium chloride supported on a metal-organic framework material; The curing trigger unit contains temperature-controlled microcapsules of aluminum powder and sodium hydroxide; Plant fiber reinforced netting, the plant fiber used is straw nanofibers with surface silanization treatment.

2. The waterproof material for house repair as described in claim 1, characterized in that, The temperature-controlled microcapsule has a polyurea-formaldehyde resin wall with a wall thickness of 0.1-0.3 μm, and the mass ratio of the core aluminum powder to sodium hydroxide is 1:0.8-1.

2.

3. The waterproof material for house repair as described in claim 1, characterized in that, The metal-organic framework material in the core-shell particles is MIL-101(Cr), and the lithium chloride loading is 35-40% of the total particle weight.

4. A waterproof material for house repair as described in claim 1, characterized in that, The plant fiber reinforced net has a filament diameter of 20-50 nm and a mesh density of 100-120 mesh. The silanization treatment uses γ-aminopropyltriethoxysilane.

5. A method for preparing a waterproof material for house repair, based on the waterproof material for house repair according to any one of claims 1 to 4, characterized in that, Includes the following steps: Step S1: Heat the silicone-modified asphalt to 160-170℃ to melt it; Step S2: Add temperature-controlled microcapsules and stir at 800-1000 rpm for 10 minutes; Step S3: After cooling to 80°C, add the core-shell particles and stir at 300 rpm until evenly dispersed; Step S4: The mixture is coated onto the surface of the plant fiber reinforced mesh and cooled to form a sheet.

6. The method for preparing a waterproof material for house repair as described in claim 5, characterized in that, The stirring process in step S2 is carried out under nitrogen protection, with a temperature fluctuation range of ≤±2℃.

7. The method for preparing a waterproof material for house repair as described in claim 5, characterized in that, The coating thickness in step S4 is 1.5-2.0 mm, and the cooling adopts a gradient cooling method: 100℃→60℃→25℃; Cooling is performed from 100℃ to 60℃ at a rate of 5℃ / min, and water cooling is used from 60℃ to 25℃.

8. A method of using a waterproof material for house repair, based on the waterproof material for house repair as described in any one of claims 1 to 4, characterized in that, include: After the sheet is attached to the leaking substrate, the core-shell particles absorb moisture through the ambient humidity. The released heat causes the temperature-controlled microcapsule wall to rupture, and sodium hydroxide catalyzes the cross-linking and penetration of the asphalt.

9. The method of using a waterproof material for house repair as described in claim 8, characterized in that, The pre-bonding surface treatment includes: removing dust and then spraying magnesium phosphate cement slurry, allowing it to stand for 2-3 minutes to form a needle-like crystalline layer.

10. The application of the waterproof material for house repair as described in claim 1 in a damp environment on the back side of a basement, characterized in that: When the relative humidity of the construction environment is ≥95%, the material will complete self-curing within 48 hours.

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