A kind of intercrystalline type waterproofing membrane and its production process

Abstract

The application discloses a kind of percolation type waterproofing membrane and production process thereof, and the integrated structure of membrane is percolation waterproofing layer, asphalt glue layer composite.The percolation waterproofing layer is composed of cement, fly ash, quartz sand, pretreated straw fiber, double-layer co-embedded type bacillus pasteurii-urea complex microbial inoculum, complex percolation active ingredient, etc.It is made by grading curing solidification process, etc.The application uses straw fiber toughening, microbial mineralization self-repairing and percolation active ingredient dense waterproofing, solves the problems of large brittleness, easy water channeling and inability to self-repairing of the membrane, and has the advantages of stable structure, strong impermeability, self-repairing microcracks, good construction adaptability, etc.

Description

Technical Field

[0001] This invention relates to the field of waterproof membrane technology, and in particular to a crystallizing waterproof membrane and its manufacturing process. Background Technology

[0002] Building waterproofing directly affects the lifespan of buildings, and waterproof membranes are a key material. Currently, the mainstream types are bituminous and polymer membranes, which rely on a physical barrier layer to block moisture. The effectiveness depends on the integrity of the membrane and its bonding strength.

[0003] However, in practical applications, traditional waterproofing membranes have four major drawbacks: First, they are easily damaged; scratches during transportation and construction or deformation and cracking of the substrate can create permanent seepage channels. Second, they cause interlayer flow; after local damage, moisture spreads between the membrane and the substrate, leading to "one damage point causing large-area leakage," making repairs extremely difficult to pinpoint. Third, they are demanding to install; most membranes require a dry substrate, and work must be stopped during the rainy season or when the groundwater level is high, severely impacting the construction period. Fourth, they cannot self-repair, being passive waterproofing, and deformation and cracking during the building's service life are unavoidable, resulting in high maintenance costs later on.

[0004] The aforementioned problems have long plagued the industry, and there is an urgent need for a waterproof material that can actively adapt to deformation and has self-healing capabilities.

[0005] Therefore, this invention is proposed to solve the above-mentioned technical problems. Summary of the Invention

[0006] One objective of this invention is to provide a crystallizing waterproof membrane, wherein the membrane is an integrated structure comprising a crystallizing waterproof layer and an asphalt adhesive layer; the crystallizing waterproof layer is composed of the following dry components in parts by weight: 40-45 parts of ordinary silicate cement, 20-25 parts of Class II fly ash, 20-25 parts of quartz sand, 5-8 parts of pretreated straw fiber, 0.5-1 parts of double-layer co-embedded Bacillus pasteurellii-urea composite microbial agent, 3-5 parts of composite crystallizing active ingredient, 0.3-0.5 parts of polyacrylonitrile fiber, 0.2-0.3 parts of polycarboxylate superplasticizer, and 0.1-0.2 parts of polyether defoamer.

[0007] Preferably, the ordinary Portland cement is P·O 42.5 grade; the Class II fly ash has a loss on ignition of ≤5% and a water requirement ratio of ≤95%; the quartz sand has a particle size of 0.15~0.3mm and a mud content of ≤0.5%.

[0008] Preferably, the pretreated straw fiber is obtained by modifying wheat straw or corn straw, with a fiber length of 5-10 mm, a diameter of 100-200 μm, and a lignin removal rate of ≥80%.

[0009] Preferably, the method for preparing the pretreated straw fiber includes the following steps:

[0010] (1) Alkali boiling to remove lignin: Chop the straw into 5-10 mm, put it into a NaOH solution with a mass concentration of 8%-10%, and boil it at a constant temperature of 95℃ for 2 hours to remove lignin and hemicellulose;

[0011] (2) Acid neutralization and washing: Rinse the straw with clean water until the pH of the washing solution is 7, then soak it in 0.5% dilute hydrochloric acid for 30 minutes to remove residual alkali, and rinse again until neutral;

[0012] (3) Silane modification and enhancement: The neutralized straw fiber is placed in a 3% KH570 silane coupling agent ethanol solution and stirred at 60°C for 1 hour to graft silanol groups onto the fiber surface.

[0013] (4) Drying for later use: Dry the modified straw fiber at 105℃ until the moisture content is ≤5%, and then seal and store it.

[0014] Preferably, the double-layer co-encapsulated Bacillus pasteurellii-urea composite bacterial agent consists of a calcium alginate core and an alkali-resistant ethyl cellulose shell. The calcium alginate core encapsulates Bacillus pasteurellii and urea, and the alkali-resistant ethyl cellulose shell contains 2% polyethylene glycol porogen by mass of ethyl cellulose. The effective viable count of Bacillus pasteurellii is ≥1×10⁻⁶. 9 CFU / g.

[0015] Preferably, the preparation method of the double-layer co-encapsulated Bacillus pasteurellii-urea composite bacterial agent includes the following steps:

[0016] (1) Preparation of bacterial culture: Bacillus pasteurellii was inoculated into LB medium and cultured at 37°C with shaking for 24 h. The bacterial cells were collected by centrifugation at 4000 rpm for 10 min and diluted with sterile phosphate-buffered saline (PBS) to a viable count of 1 × 10⁻⁶. 9 CFU / mL;

[0017] (2) Preparation of composite embedding solution: Prepare a sodium alginate solution with a mass fraction of 2.5%, autoclave and cool to room temperature, add urea and stir until completely dissolved to obtain a sodium alginate-urea mixed solution containing 5% urea by mass, for later use;

[0018] (3) Core forming: The bacterial solution in step (1) and the sodium alginate-urea mixed solution in step (2) are mixed evenly in a sterile environment at a volume ratio of 1:3. The mixture is then dropped into a CaCl2 solution with a mass fraction of 3.5% and solidified at room temperature for 30 minutes to form spherical co-embedded microspheres. The microspheres are then rinsed three times with sterile deionized water for later use.

[0019] (4) Core formation: Prepare an 8% ethyl cellulose ethanol solution, add 2% polyethylene glycol as a pore-forming agent, and stir until completely dissolved; slowly pour the core microspheres obtained in step (3) into the ethyl cellulose solution, stir at low speed for 15 minutes at 30°C, so that the surface of the microspheres is uniformly coated with an ethyl cellulose membrane.

[0020] (5) Drying and activation: The coated microspheres are collected by filtration and vacuum dried at 30°C until the moisture content is ≤10% to obtain the finished product of double-layer co-encapsulated microspheres.

[0021] Preferably, the composite crystallizing active ingredient is composed of nano-silica with a particle size of 20-50 nm and sodium silicate with a modulus of 3.2 in a mass ratio of 3:7, and citric acid is added as a slow-release agent at a mass ratio of 0.2% of the total mass of the composite crystallizing active ingredient.

[0022] This invention also provides a manufacturing process for a crystallized waterproof membrane, comprising the following steps:

[0023] S1. Dry mixing of base material: Weigh ordinary silicate cement, fly ash, quartz sand, water-reducing agent and defoamer according to the weight parts, and put them into a horizontal mixer for dry mixing for 3 minutes to obtain a uniform base material mixture.

[0024] S2. Functional system wet mixing: Add pretreated straw fiber, double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent and composite crystallizing active ingredients to the base mixture according to the weight parts, add water and wet mix for 5 minutes, control the amount of water added to 18~20% of the total weight of all dry components, control the slurry temperature ≤50℃ during the wet mixing process, adopt the shear mixing mode to obtain a uniform mixed slurry;

[0025] S3. Graded sealing, curing and solidification: The uniformly mixed slurry is directly processed into 14~50 mesh crystal-infiltrating sand particles using an extrusion granulator. The particles are sealed and wet-cured for 24 hours in a standard environment with a temperature of 20±2℃ and a relative humidity of ≥95%. Then, they are transferred to a constant temperature and humidity environment with a temperature of 25±2℃ and a relative humidity of ≥90% for curing for 7 days. Finally, they are transferred to an environment with a temperature of 20±2℃ and a relative humidity of 60±5% for equilibration for 24 hours to complete the solidification and obtain crystal-infiltrating sand for crystal-infiltrating waterproof layer.

[0026] S4. Molding: The polyurethane base fabric is impregnated in a pre-impregnation tank containing hot asphalt pre-impregnated material. Then, excess asphalt is squeezed out by a three-roll extrusion device, and the fabric is dried and shaped in a primary drying oven. The roll material is first cooled to below 50°C by a primary air-cooling device, and then dipped into a coating tank containing polyurethane coating material. The thickness of the roll material is controlled to 3mm by a thickness-fixing roller, and a polyethylene release film is immediately applied to the lower surface of the roll material after thickness fixing. At the same time, crystal sand prepared by S3 is evenly spread on its upper surface. The roll material is then cooled to below 40°C by a secondary air-cooling device, cured and shaped, and after inspection, it is cut, rolled up, packaged, and the finished product is produced.

[0027] Preferably, in the wet mixing process of step S2, shear mixing is adopted, and the mixing speed is first mixed at a medium speed of 400-600 rpm, briefly increased to 700-800 rpm for 10-30 seconds for enhanced dispersion, and then immediately returned to medium speed mixing.

[0028] Preferably, during the molding process in step S4, the drying temperature of the primary drying oven is 60~150℃.

[0029] The working mechanism of the technical solution described in this invention is as follows:

[0030] Pretreated straw fibers form a three-dimensional interwoven continuous flexible network within the crystallized waterproof layer, serving as the core toughening skeleton of the membrane. Through a bridging and crack-resistant effect, this significantly improves the membrane's elongation at break and resistance to deformation, solving the problem of high brittleness in traditional inorganic cement-based membranes. Adding a very small amount (0.3-0.5 parts) of polyacrylonitrile fiber as an auxiliary reinforcing component rapidly forms an auxiliary three-dimensional network in the early stages of slurry curing, inhibiting plastic shrinkage cracking.

[0031] This invention employs a bacterial-urea co-encapsulation technique, embedding Bacillus pasteurellii and urea within calcium alginate gel microspheres. During cement hydration, the microspheres degrade, releasing live bacteria and urea. The released bacteria then catalyze the hydrolysis of urea using urease, stabilizing the local pH of the bacteria and fiber surface within a weakly alkaline range. This protects bacterial activity and provides an optimal environment for the nucleation of hydrated calcium silicate (CSH) gel. Secondly, the bacterial cell walls carry negatively charged groups, allowing for the directional adsorption of Ca. 2+ This forms a calcium-rich nucleation template, inducing the co-precipitation and growth of CSH gel and calcite crystals on the fiber surface, forming a dense composite mineralization layer.

[0032] The active ingredients in the crystallizing membrane can penetrate into the capillaries and microcracks of the substrate with water, reacting with cement hydration products to generate insoluble crystals such as ettringite, achieving a dense and waterproof structure. Simultaneously, the incompletely degraded co-encapsulated microspheres can remain dormant inside the membrane for a long time. When the membrane develops microcracks due to external forces, the dormant bacteria and urea are released again, autonomously sealing the microcracks.

[0033] The present invention features a composite, integrated structure consisting of a crystal-penetrating waterproof layer and an asphalt adhesive layer. During roll application, concrete is poured onto the surface of the crystal-penetrating roll, where the crystal-penetrating sand reacts with the concrete to form a rigid waterproof layer. The underlying asphalt adhesive layer further reinforces this waterproof layer, creating two waterproof barriers. One barrier is formed by the reaction of the crystal-penetrating coating with the concrete, while the roll beneath the crystal-penetrating sand forms another waterproof barrier.

[0034] The beneficial effects of this invention are:

[0035] This invention utilizes a microbial-substrate co-encapsulation technology to endow the waterproof membrane with a self-healing function that actively senses and repairs microcracks. The polyethylene glycol pore-forming agent added to the ethyl cellulose outer shell slowly dissolves during long-term use, forming interconnected microporous channels. When cracks appear in the waterproof layer and water seeps in, the water enters the core through the micropores, dissolving the calcium alginate gel and releasing Bacillus pasteurellii and urea. Under suitable humidity and temperature, Bacillus pasteurellii activates, decomposing urea to produce carbonate ions, which react with calcium ions in the cement system to form calcium carbonate crystals, filling the cracks and restoring waterproof performance. The synergistic effect of a flexible and toughened skeleton constructed from straw fiber, microbial directional mineralization and crystallization active ingredients achieving bulk density and waterproofing solves the problem of poor interfacial compatibility, improving the performance of the waterproof membrane. The integrated molding structure of the crystallized waterproof layer and the asphalt adhesive layer eliminates the risk of water seepage, enhancing the structural stability and construction adaptability of the membrane. Attached Figure Description

[0036] Figure 1 This is a picture of a waterproof membrane product. Detailed Implementation

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] The polycarboxylate superplasticizer and polyether defoamer are both commercially available products in the field, and the Bacillus pasteurellis is a commercially available strain. Those skilled in the art can select and determine the appropriate strain through routine testing based on actual performance requirements.

[0039] Example 1

[0040] 1. Raw material preparation

[0041] Dry components of the crystallizing waterproof layer (parts by weight): 40 parts of P·O 42.5 ordinary silicate cement, 20 parts of Class II fly ash (loss on ignition ≤5%, water requirement ≤95%), 20 parts of quartz sand (particle size 0.15~0.3mm, mud content ≤0.5%), 5 parts of pretreated straw fiber, 0.5 parts of double-layer co-embedded Bacillus pasteurellii-urea composite microbial agent, 3 parts of composite crystallizing active ingredient, 0.3 parts of polyacrylonitrile fiber, 0.2 parts of polycarboxylate superplasticizer, and 0.1 parts of polyether defoamer.

[0042] Preparation of pretreated straw fiber:

[0043] Chop wheat straw into 5-10 mm pieces, place it in an 8% NaOH solution, and boil it at 95°C for 2 hours. Rinse with water until the washing solution pH=7, then soak it in 0.5% dilute hydrochloric acid for 30 minutes, and rinse again until neutral. Place the neutralized straw fiber in a 3% KH570 silane coupling agent ethanol solution and stir at 60°C for 1 hour. Finally, dry it at 105°C until the moisture content is ≤5%, and store it in a sealed container for later use.

[0044] Preparation of a double-layer co-encapsulated Bacillus pasteurellii-urea composite bacterial agent:

[0045] Bacillus pasteurellii was inoculated into LB medium and cultured at 37°C with shaking for 24 h. The cells were collected by centrifugation at 4000 rpm for 10 min and diluted with sterile PBS buffer to a viable count of 1 × 10⁻⁶. 9 CFU / mL; Prepare a 2.5% sodium alginate solution, autoclave and cool to room temperature, add urea and stir until completely dissolved to obtain a sodium alginate-urea mixed solution containing 5% urea; Mix the bacterial solution and the sodium alginate-urea mixed solution at a volume ratio of 1:3 under sterile conditions, add dropwise to a 3.5% CaCl2 solution, and solidify at room temperature for 30 min to form spherical co-encapsulated microspheres; Rinse three times with sterile deionized water for later use; Prepare an 8% ethyl cellulose ethanol solution, add 2% polyethylene glycol (by mass of ethyl cellulose) as a pore-forming agent, and stir until completely dissolved; Slowly pour the prepared microspheres into the ethyl cellulose solution, stir at low speed at 30℃ for 15 min to uniformly coat the surface of the microspheres with a layer of ethyl cellulose membrane; Filter and collect the microspheres, vacuum dry at 30℃ until the moisture content is ≤10%, to obtain the finished double-layer co-encapsulated microspheres.

[0046] Preparation of composite crystallization active ingredients:

[0047] The composite crystallizing active ingredient is composed of nano-silica with a particle size of 20~50nm and sodium silicate with a modulus of 3.2 in a mass ratio of 3:7, and citric acid is added as a slow-release agent at a mass ratio of 0.2% of the total mass of the composite crystallizing active ingredient.

[0048] Preparation of the pre-impregnation tank and polyurethane coating tank:

[0049] Hot asphalt prepreg (parts by weight): 70 parts of 90# road petroleum asphalt, 11 parts of linear SBS thermoplastic elastomer (30% styrene content), 11 parts of naphthenic oil KN4010, 7.5 parts of talc, 0.3 parts of antioxidant 1010, and 0.2 parts of silane coupling agent KH550.

[0050] Polyurethane coating material (two-component, weight ratio A:B=1:0.8): Component A (main agent): 42 parts of polyether polyol N220, 28 parts of diphenylmethane diisocyanate MDI-100, 24.5 parts of ethyl acetate, 0.4 parts of silicone defoamer BYK-066N, and 0.1 parts of dibutyltin dilaurate; Component B (curing agent): 52 parts of polyester polyol PBA-2000, 9 parts of 1,4-butanediol, 34.5 parts of ethyl acetate, 2 parts of silane coupling agent KH570, and 2.5 parts of nano silica (20~50nm).

[0051] 2. Production process:

[0052] S1. Dry mixing of base material: Weigh cement, fly ash, quartz sand, water-reducing agent and defoamer according to the above weight parts, and put them into a horizontal mixer for dry mixing for 3 minutes;

[0053] S2. Functional system wet mixing: Add pretreated straw fiber, co-encapsulated microbial agent, and composite crystallizing active ingredient to the substrate mixture, add water (18% of the total dry weight), mix at a medium speed of 400-600 rpm, briefly increase to 700-800 rpm for 10-30 seconds for enhanced dispersion, and then immediately return to medium speed stirring. Wet mixing for a total of 5 minutes, controlling the slurry temperature ≤50℃.

[0054] S3. Graded sealing and curing: The uniformly mixed slurry is directly processed into 14~50 mesh crystal-infiltrating sand particles using an extrusion granulator. The particles are sealed and wet-cured at 20±2℃ and ≥95% humidity for 24 hours; then transferred to 25±2℃ and ≥90% humidity for 7 days; finally, it is equilibrated at 20±2℃ and 60±5% humidity for 24 hours to complete the curing and obtain crystal-infiltrating sand.

[0055] S4. The polyurethane base fabric is impregnated in a pre-impregnation tank containing hot asphalt pre-impregnated material. Excess asphalt is then removed by a three-roll extrusion device, and the fabric is dried and shaped in a primary drying oven at 100°C. The roll material is first cooled to below 50°C using a primary air-cooling device, then immersed in a coating tank containing polyurethane coating material (mixed at a low speed for 3 minutes before use, with A:B = 1:0.8 by weight). The roll material thickness is then controlled to 3mm using a thickness-fixing roller. Immediately after thickness fixing, a polyethylene release film is applied to the lower surface of the roll material, and simultaneously, the crystal-infiltrating sand prepared in S3 is evenly spread on its upper surface at a rate of 500-800 g / m². 2 The roll material is then cooled to below 40°C using a secondary air-cooling device, solidified, and after testing, cut, rolled, packaged, and the finished product is produced. The actual product is shown below. Figure 1 As shown.

[0056] Example 2

[0057] 1. Raw material preparation:

[0058] Dry components of the crystallizing waterproof layer (parts by weight): 42.5 parts of P·O 42.5 ordinary silicate cement, 22.5 parts of Class II fly ash, 22.5 parts of quartz sand, 6.5 parts of pretreated straw fiber, 0.75 parts of double-layer co-embedded Bacillus pasteurellii-urea composite microbial agent, 4 parts of composite crystallizing active ingredient, 0.4 parts of polyacrylonitrile fiber, 0.25 parts of polycarboxylate superplasticizer, and 0.15 parts of polyether defoamer.

[0059] The preparation methods for pretreated straw fiber, co-encapsulated microbial agent, and composite crystallization active ingredient are the same as in Example 1.

[0060] 2. Production process:

[0061] S1. Dry mixing of substrate: Same as in Example 1;

[0062] S2, Functional system wet mixing: The amount of water added is 19% of the total dry weight, and the rest is the same as in Example 1;

[0063] S3. Graded sealing, curing, and solidification: Same as in Example 1;

[0064] S4. Molding: Same as in Example 1.

[0065] Example 3

[0066] 1. Raw material preparation:

[0067] Dry components of the crystallizing waterproof layer (parts by weight): 45 parts of P·O 42.5 ordinary silicate cement, 25 parts of Class II fly ash, 25 parts of quartz sand, 8 parts of pretreated straw fiber, 1.0 part of double-layer co-embedded Bacillus pasteurellii-urea composite microbial agent, 5 parts of composite crystallizing active ingredient, 0.5 parts of polyacrylonitrile fiber, 0.3 parts of polycarboxylate superplasticizer, and 0.2 parts of polyether defoamer.

[0068] The preparation methods for pretreated straw fiber, co-encapsulated microbial agent, and composite crystallization active ingredient are the same as in Example 1.

[0069] Production process:

[0070] S1. Dry mixing of substrate: Same as in Example 1;

[0071] S2, Wet mixing of functional system: The amount of water added is 20% of the total dry weight, and the rest is the same as in Example 1;

[0072] S3. Graded sealing, curing, and solidification: Same as in Example 1;

[0073] S4. Molding: Same as in Example 1.

[0074] Comparative Example 1 (without straw fiber skeleton)

[0075] The difference from Example 2 is that "pretreated straw fiber" is not added to the crystallized waterproof layer, while the other components and preparation process are the same as in Example 2.

[0076] Comparative Example 2 (System without Microbial Mineralization)

[0077] The difference from Example 2 is that the "double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent" is not added to the crystallized waterproof layer, while the other components and preparation process are the same as in Example 2.

[0078] Comparative Example 3 (without crystallization active ingredients)

[0079] The difference from Example 2 is that no "composite crystallizing active ingredient" is added to the crystallizing waterproof layer, while the other components and preparation process are the same as in Example 2.

[0080] Comparative Example 4 (Bacteria and urea added directly, not co-encapsulated)

[0081] The difference from Example 2 is that the "double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent" is not added to the crystallization waterproof layer. Instead, an equal amount of Bacillus pasteurellii bacterial powder (live count ≥ 1 × 10⁻⁶) is directly added during the S2 wet mixing process. 9 The ingredients and preparation process are the same as in Example 2, consisting of CFU / g and urea powder.

[0082] Actual test

[0083] The waterproof membranes obtained in Examples 1-3 and Comparative Examples 1-4 were subjected to the following performance tests:

[0084] (1) Test the tensile strength, elongation at break, tear strength and other indicators of the membrane according to the method specified in GB / T 23457-2009 "Pre-laid / wet-laid waterproof membrane"; and conduct waterproof performance tests according to the test methods in GB / T 23457-2017 "Pre-laid waterproof membrane";

[0085] (2) Interfacial shear strength: Tested according to the method specified in GB / T 328.23-2007 "Test Methods for Waterproof Building Membranes";

[0086] (3) Self-healing performance test: Refer to GB / T 18445-2025 "Cement-based penetrating crystalline waterproof materials" to evaluate the repair rate of micro-cracks (≤0.3mm) of the roll material.

[0087] The test results are shown in Table 1.

[0088] Table 1

[0089]

[0090] As shown in Table 1, the tensile strength, elongation at break, and tear strength of Comparative Example 1 (without straw fiber) decreased compared to Example 2. This difference stems from the lack of bridging and crack-preventing effect of the fiber skeleton. In cement-based composites, microcrack initiation is inevitable. However, straw fiber, as a high-toughness phase, can disperse stress at the crack tip through stress transfer at the fiber-matrix interface, forcing the crack to deflect or bypass along the fiber surface, thereby extending the crack propagation path and consuming fracture energy. When the fiber is missing, the crack, once initiated, propagates rapidly in a straight line, exhibiting brittle fracture characteristics. In the absence of the microbial mineralization system, the straw fiber, as an organic material, is only physically interlocked with the cement-based inorganic material through van der Waals forces, resulting in low interfacial shear strength. In the examples, *Bacillus pasteurellii* directionally adsorbs Ca through the negatively charged groups of its cell wall. 2+A calcium-rich nucleation template is formed on the fiber surface, inducing the co-precipitation growth of CSH gel and calcite crystals. The Si-OH at the end of the silica chain of the CSH gel undergoes a condensation reaction with the silanol groups grafted onto the fiber surface (-Si-OH+HO-Si-→-Si-O-Si-+H2O), forming chemical bonds, thus significantly improving the interfacial shear strength. The essence of self-healing is the restart of the mineralization reaction at the crack. The crystallizing active material in Comparative Example 2 has a certain ability to self-heal microcracks, but it lacks a double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent, so the repair effect is not good. Although Comparative Example 4 contains bacteria and urea, the direct addition causes the urea to hydrolyze prematurely in the high-alkali environment of cement. By the time the bacteria are released, the substrate has been largely consumed. The co-embedding technology of the present example avoids the premature hydrolysis of urea in the high-alkali environment. When water seeps into the crack, the microspheres absorb water and swell, the bacteria recover and catalyze the hydrolysis of residual urea.

[0091] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A crystallization-type waterproof membrane, characterized in that, The roll material is an integrated structure composed of a crystallized waterproof layer and an asphalt adhesive layer. The crystallized waterproof layer is composed of the following dry components in parts by weight: 40-45 parts ordinary silicate cement, 20-25 parts grade II fly ash, 20-25 parts quartz sand, 5-8 parts pretreated straw fiber, 0.5-1 parts double-layer co-embedded Bacillus pasteurellii-urea composite microbial agent, 3-5 parts composite crystallizing active ingredient, 0.3-0.5 parts polyacrylonitrile fiber, 0.2-0.3 parts polycarboxylate superplasticizer, and 0.1-0.2 parts polyether defoamer.

2. The crystallizing waterproof membrane according to claim 1, characterized in that, The ordinary Portland cement is of grade P·O42.5; the grade II fly ash has a loss on ignition of ≤5% and a water requirement of ≤95%; the quartz sand has a particle size of 0.15~0.3mm and a mud content of ≤0.5%.

3. The crystallizing waterproof membrane according to claim 1, characterized in that, The pretreated straw fiber is obtained by modifying wheat straw or corn straw, with a fiber length of 5~10mm, a diameter of 100~200μm, and a lignin removal rate of ≥80%.

4. The crystallizing waterproof membrane according to claim 3, characterized in that, The method for preparing the pretreated straw fiber includes the following steps: (1) Alkali boiling to remove lignin: Chop the straw into 5-10 mm, put it into a NaOH solution with a mass concentration of 8%-10%, and boil it at a constant temperature of 95℃ for 2 hours to remove lignin and hemicellulose; (2) Acid neutralization and washing: Rinse the straw with clean water until the pH of the washing solution is 7, then soak it in 0.5% dilute hydrochloric acid for 30 minutes to remove residual alkali, and rinse again until neutral; (3) Silane modification and enhancement: The neutralized straw fiber is placed in a 3% KH570 silane coupling agent ethanol solution and stirred at 60°C for 1 hour to graft silanol groups onto the fiber surface. (4) Drying for later use: Dry the modified straw fiber at 105℃ until the moisture content is ≤5%, and then seal and store it.

5. The crystallizing waterproof membrane according to claim 1, characterized in that, The double-layer co-encapsulated Bacillus pasteurellii-urea composite bacterial agent consists of a calcium alginate core and an alkali-resistant ethyl cellulose shell. The calcium alginate core encapsulates Bacillus pasteurellii and urea, and the alkali-resistant ethyl cellulose shell contains 2% polyethylene glycol porogen by weight of ethyl cellulose. The effective viable count of Bacillus pasteurellii is ≥1×10⁻⁶. 9 CFU / g.

6. The crystallizing waterproof membrane according to claim 5, characterized in that, The preparation method of the double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent includes the following steps: (1) Preparation of bacterial culture: Bacillus pasteurellii was inoculated into LB medium and cultured at 37°C with shaking for 24 h. The bacterial cells were collected by centrifugation at 4000 rpm for 10 min and diluted with sterile phosphate-buffered saline (PBS) to a viable count of 1 × 10⁻⁶. 9 CFU / mL; (2) Preparation of composite embedding solution: Prepare a sodium alginate solution with a mass fraction of 2.5%, autoclave and cool to room temperature, add urea and stir until completely dissolved to obtain a sodium alginate-urea mixed solution containing 5% urea by mass, for later use; (3) Core forming: Mix the bacterial solution from step (1) and the sodium alginate-urea mixed solution from step (2) at a volume ratio of 1:3 under sterile conditions, drop them into a 3.5% CaCl2 solution, solidify at room temperature for 30 minutes, and rinse three times with sterile deionized water for later use. (4) Core formation: Prepare an 8% ethyl cellulose ethanol solution, add 2% polyethylene glycol as a pore-forming agent, and stir until completely dissolved; slowly pour the core microspheres obtained in step (3) into the ethyl cellulose solution, stir at low speed for 15 minutes at 30°C, so that the surface of the microspheres is uniformly coated with an ethyl cellulose membrane. (5) Drying and activation: The coated microspheres are collected by filtration and vacuum dried at 30°C until the moisture content is ≤10% to obtain the finished product of double-layer co-encapsulated microspheres.

7. The crystallizing waterproof membrane according to claim 1, characterized in that, The composite crystallizing active ingredient is composed of nano-silica with a particle size of 20-50nm and sodium silicate with a modulus of 3.2 in a mass ratio of 3:7, and citric acid is added as a slow-release agent at a mass ratio of 0.2% of the total mass of the composite crystallizing active ingredient.

8. A manufacturing process for the crystallization-type waterproof membrane according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Dry mixing of base material: Weigh ordinary silicate cement, fly ash, quartz sand, water-reducing agent and defoamer according to the weight parts, and put them into a horizontal mixer for dry mixing for 3 minutes to obtain a uniform base material mixture. S2. Functional system wet mixing: Add pretreated straw fiber, double-layer co-embedded Bacillus pasteurellii-urea composite bacterial agent and composite crystallizing active ingredients to the base mixture according to the weight parts, add water and wet mix for 5 minutes, control the amount of water added to 18~20% of the total weight of all dry components, control the slurry temperature ≤50℃ during the wet mixing process, adopt the shear mixing mode to obtain a uniform mixed slurry; S3. Graded sealing, curing and solidification: The uniformly mixed slurry is directly processed into 14~50 mesh crystal-infiltrating sand particles using an extrusion granulator. The particles are sealed and wet-cured for 24 hours in a standard environment with a temperature of 20±2℃ and a relative humidity of ≥95%. Then, they are transferred to a constant temperature and humidity environment with a temperature of 25±2℃ and a relative humidity of ≥90% for curing for 7 days. Finally, they are transferred to an environment with a temperature of 20±2℃ and a relative humidity of 60±5% for equilibration for 24 hours to complete the solidification and obtain crystal-infiltrating sand for crystal-infiltrating waterproof layer. S4. Molding: The polyurethane base fabric is impregnated in the pre-impregnation oil bath of hot asphalt prepreg. Then, excess asphalt is squeezed out by a three-roll extrusion device, and the fabric is dried and shaped in a primary drying oven. The roll material is first cooled to below 50°C by a primary air-cooling device, and then dipped into a coating tank containing polyurethane coating material. The thickness of the roll material is controlled to 3mm by a thickness-fixing roller, and a polyethylene release film is immediately applied to the lower surface of the roll material after thickness fixing. At the same time, the crystallizing sand prepared by S3 is evenly spread on its upper surface. The roll material is then cooled to below 40°C by a secondary air-cooling device, cured and shaped. After inspection, it is cut, rolled up, packaged, and the finished product is produced.

9. The production process according to claim 8, characterized in that, In step S2, during wet mixing, shear mixing is employed. The mixing speed is initially set at a medium speed of 400-600 rpm, then briefly increased to 700-800 rpm for 10-30 seconds for enhanced dispersion, and then immediately returned to medium speed mixing.

10. The production process according to claim 8, characterized in that, During the molding process in step S4, the drying temperature of the primary drying oven is 60~150℃.

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