Carbon nanodot-based antibacterial waterproof coiled material and preparation method thereof

Abstract

The invention relates to the technical field of waterproof coiled materials, and discloses a carbon nanodot-based antibacterial waterproof coiled material and a preparation method thereof.The waterproof coiled material comprises a waterproof antibacterial functional layer, a bonding layer and a polyester non-woven fabric base material layer which are sequentially arranged from top to bottom; wherein the waterproof antibacterial functional layer is prepared from the following raw materials in parts by mass: 82 to 85 parts of SBS (Styrene Butadiene Styrene) modified asphalt, 1.2 to 1.8 parts of carbon nanodots, 1.0 to 1.5 parts of aminated nano zinc oxide, 2.5 to 3.0 parts of nano silicon dioxide, 0.3 to 0.5 part of silane coupling agent, 0.2 to 0.3 part of antioxidant, 0.3 to 0.5 part of dispersing agent, 0.1 to 0.2 part of mildew preventive and 7.0 to 10 parts of light calcium carbonate. According to the invention, not only can the antibacterial performance of the waterproof roll be improved, but also the good waterproof performance can be maintained, but also the tensile strength and wear resistance of the waterproof roll can be enhanced while the waterproof impermeability is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waterproofing membrane, in particular to a carbon nanodot-based antibacterial waterproofing membrane and a preparation method thereof. BACKGROUND

[0002] As the core material of building envelope system, waterproofing membrane is widely used in key parts such as roof, basement and tunnel, and its performance is directly related to the structural safety, use function and durability of the building. With the continuous upgrading of the functional requirements of the building industry on materials, waterproofing membranes with both waterproofing and antibacterial properties are increasingly valued. However, the traditional waterproofing membranes have the following problems: 1) Poor synergy between antibacterial and waterproofing functions: Traditional antibacterial waterproofing membranes mostly add single organic or inorganic antibacterial agents. Organic antibacterial agents are prone to decomposition and failure in high-temperature processing or long-term use, and inorganic antibacterial agents are prone to cause a decrease in waterproofing density due to poor compatibility with the asphalt matrix, resulting in leakage risks; 2) Non-uniform dispersion of nanofunctional fillers: Traditional functional nanomaterials are prone to agglomeration due to their large specific surface area and strong van der Waals force, which not only fails to improve the performance by small size effect, but also leads to uneven internal structure of the waterproofing membrane and large dispersion of mechanical properties and functional stability; 3) Insufficient interlayer adhesion: The functional layer and the base layer of the traditional waterproofing membrane are mostly physically attached, lacking effective chemical bonding sites, which are prone to interlayer peeling and blistering under the effects of temperature changes, structural settlement or long-term water immersion.

[0003] In view of the problems in the related art, no effective solution has been proposed so far. SUMMARY

[0004] In view of the problems in the related art, the present application proposes a carbon nanodot-based antibacterial waterproofing membrane and a preparation method thereof to overcome the above technical problems existing in the prior art.

[0005] To this end, the specific technical solutions adopted by the present application are as follows: According to a first aspect of the present application, a carbon nanodot-based antibacterial waterproofing membrane is provided, comprising, from top to bottom, a waterproofing and antibacterial functional layer, an adhesive layer and a polyester non-woven fabric base layer; The waterproofing and antibacterial functional layer is composed of the following raw materials in mass fraction: SBS modified asphalt 82-85 parts, carbon nanodots 1.2-1.8 parts, amino-functionalized nano-zinc oxide 1.0-1.5 parts, nano-silicon dioxide 2.5-3.0 parts, silane coupling agent 0.3-0.5 parts, antioxidant 0.2-0.3 parts, dispersant 0.3-0.5 parts, mildew-resistant agent 0.1-0.2 parts and light calcium carbonate 7.0-10 parts.

[0006] Furthermore, the silane coupling agent is any one of aminopropyltriethoxysilane, epoxypropyltrimethoxysilane, or methacryloxypropyltrimethoxysilane; preferably, the silane coupling agent is aminopropyltriethoxysilane.

[0007] Furthermore, the antioxidant is a mixture of hindered phenolic antioxidants and phosphite antioxidants; preferably, the antioxidant is a hindered phenolic antioxidant.

[0008] Furthermore, the dispersant is any one of fatty alcohol polyoxyethylene ether, sorbitan monooleate, sodium dodecylbenzenesulfonate, or tea saponin; preferably, the dispersant is fatty alcohol polyoxyethylene ether.

[0009] Furthermore, the antifungal agent is any one of Kathon CG, bifonazole, or chlorothalonil; preferably, the antifungal agent is Kathon CG, which is a compound antibacterial agent composed of 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT) and 2-methyl-4-isothiazolin-3-one (MIT) in a 3:1 ratio.

[0010] Furthermore, the adhesive layer is composed of the following parts by weight of raw materials: The composition includes 42-45 parts hot melt pressure-sensitive adhesive, 6.0-8.0 parts thermoplastic elastomer, 10-12 parts tackifying resin, 6.0-7.0 parts softener, 4.0-5.0 parts polymer microspheres, 0.6-0.8 parts organic modified nano-montmorillonite, 18-22 parts light calcium carbonate, and 0.2-0.3 parts antioxidant.

[0011] Furthermore, the thermoplastic elastomer is any one of SEBS, EPDM rubber, thermoplastic polyurethane, or polyolefin elastomer; preferably, the thermoplastic elastomer is SEBS.

[0012] Furthermore, the softener is any one of naphthenic oil, paraffin oil, dioctyl phthalate, or soybean oil; preferably, the softener is naphthenic oil.

[0013] Furthermore, the polymer microspheres are any one of acrylate microspheres, styrene microspheres, polyurethane microspheres, or silicone rubber microspheres; preferably, the polymer microspheres are acrylate microspheres.

[0014] According to a second aspect of the present invention, a method for preparing a carbon nanoparticle-based antibacterial and waterproof membrane is provided, comprising the following steps: S1. Weigh the raw materials of the waterproof and antibacterial functional layer in the predetermined mass proportions, mix carbon nanodots, aminated nano zinc oxide, nano silica and dispersant, form nanoparticle dispersion by high-speed shearing and stirring, and dilute the silane coupling agent with deionized water and adjust the pH before stirring and activating. S2. Add the molten SBS modified asphalt to a high-speed mixer, then add the activated silane coupling agent and nanoparticle dispersion in sequence and stir evenly. Then add the antioxidant, mildew inhibitor and light calcium carbonate in sequence and stir evenly to obtain a waterproof and antibacterial functional layer slurry. S3. Weigh the raw materials of the adhesive layer in the preset mass proportions, add the hot melt pressure-sensitive adhesive, thermoplastic elastomer and softener to the mixing tank, and melt and stir at the preset temperature until the thermoplastic elastomer is dissolved. Then add the tackifying resin, polymer microspheres, organic modified nano montmorillonite, light calcium carbonate and antioxidant and stir evenly to obtain the adhesive layer slurry. S4. The polyester nonwoven fabric substrate layer is laid flat on the coating machine conveyor belt. The adhesive layer slurry is first coated and then pre-cured in the preheating channel. The waterproof and antibacterial functional layer slurry is then coated and fed into the composite pressure roller for pressing and bonding. The composite roll is then sent to the cooling conveyor belt for air cooling to room temperature and cut according to the preset specifications to obtain carbon nanoparticle-based antibacterial and waterproof roll.

[0015] The beneficial effects of this invention are as follows: 1) In the waterproof and antibacterial functional layer of this invention, carbon nanoparticles and aminated nano-zinc oxide form a composite antibacterial system. The carbon nanoparticles and aminated nano-zinc oxide simultaneously generate reactive oxygen species that destroy bacterial cell membranes. Furthermore, the aminated nano-zinc oxide slowly releases Zn²⁺ to inhibit microbial metabolism. Combined with highly effective antifungal agents such as Kathon CG, it achieves broad-spectrum inhibition against common pathogenic bacteria such as Escherichia coli and Staphylococcus aureus, as well as molds such as Aspergillus niger and Penicillium. This effectively improves the antibacterial performance of the waterproof membrane. Moreover, the antibacterial component is well compatible with the SBS modified bitumen matrix, thus maintaining excellent waterproof performance while improving the antibacterial performance of the waterproof membrane.

[0016] 2) This invention can chemically bond the functional groups activated by the hydrolysis of silane coupling agents with the surface groups of carbon nanoparticles, aminated nano zinc oxide, and nano silica. Combined with the physical dispersion effect of dispersants such as fatty alcohol polyoxyethylene ether, it can effectively solve the problem of nanoparticle agglomeration. This allows the uniformly dispersed nanoparticles to synergistically fill the voids in the asphalt matrix with light calcium carbonate, enhancing the structural density of the functional layer. This can improve the waterproof and seepage-proof performance while enhancing the tensile strength and abrasion resistance of the waterproof membrane.

[0017] 3) The adhesive layer of the present invention is made by blending hot melt pressure-sensitive adhesive with thermoplastic elastomer, and is combined with tackifying resin and softener to adjust the balance between viscosity and flexibility. In addition, the polymer microspheres can form a micro-protrusion structure on the surface of the adhesive layer to increase the interfacial contact area, and the layered barrier effect of organically modified nano-montmorillonite can improve the impermeability. The three work together to form a strong chemical and physical bond between the adhesive layer, the waterproof and antibacterial functional layer and the polyester non-woven fabric substrate layer, effectively improving the interlayer peel strength and avoiding interlayer peeling and blistering. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. 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 flowchart of a method for preparing a carbon nanodot-based antibacterial and waterproof membrane according to an embodiment of the present invention. Detailed Implementation

[0020] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0021] According to embodiments of the present invention, a carbon nanoparticle-based antibacterial waterproof membrane and its preparation method are provided.

[0022] The present invention will now be further described with reference to the accompanying drawings and specific embodiments. According to one aspect of the present invention, a carbon nanoparticle-based antibacterial and waterproof membrane is provided, comprising a waterproof and antibacterial functional layer, an adhesive layer and a polyester nonwoven fabric substrate layer arranged sequentially from top to bottom; The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: 82-85 parts of SBS modified asphalt, 1.2-1.8 parts of carbon nanoparticles, 1.0-1.5 parts of aminated nano zinc oxide, 2.5-3.0 parts of nano silica, 0.3-0.5 parts of silane coupling agent, 0.2-0.3 parts of antioxidant, 0.3-0.5 parts of dispersant, 0.1-0.2 parts of mildew inhibitor, and 7.0-10 parts of light calcium carbonate.

[0023] Specifically, the silane coupling agent is any one of aminopropyltriethoxysilane, propylene oxide propyltrimethoxysilane, or methacryloxypropyltrimethoxysilane. The antioxidant is a mixture of hindered phenolic antioxidants and phosphite antioxidants. The dispersant is any one of fatty alcohol polyoxyethylene ether, sorbitan monooleate, sodium dodecylbenzenesulfonate, or tea saponin. The fungicide is any one of Kathon CG, bifonazole, or chlorothalonil.

[0024] The adhesive layer is composed of the following raw materials in parts by weight: The composition includes 42-45 parts hot melt pressure-sensitive adhesive, 6.0-8.0 parts thermoplastic elastomer, 10-12 parts tackifying resin, 6.0-7.0 parts softener, 4.0-5.0 parts polymer microspheres, 0.6-0.8 parts organic modified nano-montmorillonite, 18-22 parts light calcium carbonate, and 0.2-0.3 parts antioxidant.

[0025] Specifically, the thermoplastic elastomer is any one of SEBS, EPDM rubber, thermoplastic polyurethane, or polyolefin elastomer. The softener is any one of naphthenic oil, paraffin oil, dioctyl phthalate, or soybean oil. The polymer microspheres are any one of acrylate microspheres, styrene microspheres, polyurethane microspheres, or silicone rubber microspheres.

[0026] To facilitate understanding of the above technical solutions of the present invention, the following detailed description is provided in conjunction with specific embodiments.

[0027] Example 1 A carbon nanoparticle-based antibacterial and waterproof membrane includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester nonwoven fabric substrate layer. The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: The composition includes 83.5 g of SBS modified bitumen, 1.5 g of carbon nanoparticles, 1.2 g of aminated nano zinc oxide, 2.7 g of nano silica, 0.4 g of aminopropyltriethoxysilane, 0.25 g of hindered phenolic antioxidant, 0.4 g of fatty alcohol polyoxyethylene ether, 0.15 g of Kathon CG, and 8.5 g of light calcium carbonate.

[0028] The adhesive layer is composed of the following parts by weight of raw materials: 43.5 g of hot melt pressure-sensitive adhesive, 7.0 g of SEBS, 11.0 g of tackifying resin, 6.5 g of naphthenic oil, 4.5 g of acrylate microspheres, 0.7 g of organically modified nano-montmorillonite, 20.0 g of light calcium carbonate, and 0.25 g of hindered phenolic antioxidant.

[0029] Example 2 A carbon nanoparticle-based antibacterial and waterproof membrane includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester nonwoven fabric substrate layer. The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: 82.0 g of SBS modified bitumen, 1.8 g of carbon nanoparticles, 1.0 g of aminated nano zinc oxide, 3.0 g of nano silica, 0.3 g of aminopropyltriethoxysilane, 0.3 g of hindered phenolic antioxidant, 0.5 g of fatty alcohol polyoxyethylene ether, 0.1 g of Kathon CG and 10.0 g of light calcium carbonate.

[0030] The adhesive layer is composed of the following parts by weight of raw materials: 42.0 g of hot melt pressure-sensitive adhesive, 8.0 g of SEBS, 10.0 g of tackifying resin, 7.0 g of naphthenic oil, 4.0 g of acrylate microspheres, 0.8 g of organically modified nano-montmorillonite, 22.0 g of light calcium carbonate, and 0.2 g of hindered phenolic antioxidant.

[0031] Example 3 A carbon nanoparticle-based antibacterial and waterproof membrane includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester nonwoven fabric substrate layer. The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: 84.0 g of SBS modified bitumen, 1.3 g of carbon nanoparticles, 1.4 g of aminated nano zinc oxide, 2.6 g of nano silica, 0.5 g of aminopropyltriethoxysilane, 0.22 g of hindered phenolic antioxidant, 0.35 g of fatty alcohol polyoxyethylene ether, 0.18 g of Kathon CG, and 7.5 g of light calcium carbonate.

[0032] The adhesive layer is composed of the following parts by weight of raw materials: 44.0 g of hot melt pressure-sensitive adhesive, 6.5 g of SEBS, 11.5 g of tackifying resin, 6.2 g of naphthenic oil, 4.8 g of acrylate microspheres, 0.65 g of organically modified nano-montmorillonite, 19.0 g of light calcium carbonate, and 0.28 g of hindered phenolic antioxidant.

[0033] Example 4 A carbon nanoparticle-based antibacterial and waterproof membrane includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester nonwoven fabric substrate layer. The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: 85.0 g of SBS modified bitumen, 1.4 g of carbon nanoparticles, 1.1 g of aminated nano zinc oxide, 2.8 g of nano silica, 0.35 g of aminopropyltriethoxysilane, 0.27 g of hindered phenolic antioxidant, 0.45 g of fatty alcohol polyoxyethylene ether, 0.12 g of Kathon CG, and 9.2 g of light calcium carbonate.

[0034] The adhesive layer is composed of the following parts by weight of raw materials: 45.0 g of hot melt pressure-sensitive adhesive, 6.2 g of SEBS, 10.5 g of tackifying resin, 6.8 g of naphthenic oil, 4.2 g of acrylate microspheres, 0.75 g of organically modified nano-montmorillonite, 21.0 g of light calcium carbonate, and 0.23 g of hindered phenolic antioxidant.

[0035] Example 5 A carbon nanoparticle-based antibacterial and waterproof membrane includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester nonwoven fabric substrate layer. The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: The composition includes 82.5 g of SBS modified bitumen, 1.7 g of carbon nanoparticles, 1.3 g of aminated nano zinc oxide, 2.9 g of nano silica, 0.45 g of aminopropyltriethoxysilane, 0.24 g of hindered phenolic antioxidant, 0.38 g of fatty alcohol polyoxyethylene ether, 0.19 g of Kathon CG, and 9.8 g of light calcium carbonate.

[0036] The adhesive layer is composed of the following parts by weight of raw materials: The composition includes 43.0 g of hot melt pressure-sensitive adhesive, 7.8 g of SEBS, 11.8 g of tackifying resin, 6.3 g of naphthenic oil, 4.9 g of acrylate microspheres, 0.68 g of organically modified nano-montmorillonite, 18.5 g of light calcium carbonate, and 0.29 g of hindered phenolic antioxidant.

[0037] Comparative Example An antibacterial and waterproof membrane is composed of the following raw materials in parts by weight: 100 g of 90# base asphalt, 5 g of SBS modifier, 10 g of asphalt softening oil, 45 g of rubber powder, 5 g of light calcium carbonate, 0.5 g of silver ion antibacterial agent, and 0.3 g of Kathon CG.

[0038] Experimental Section 1. Sample selection: Samples from Examples 1-5 and the comparative examples were selected respectively. The size of each sample was uniformly 200mm×200mm to ensure that the preparation process was consistent. 2. Testing Indicators and Standards: Four key indicators were selected: antibacterial rate, hydrostatic pressure resistance, interlayer peel strength, and aging tensile strength retention rate. These were tested using national standards, as detailed below: Antibacterial rate: Antibacterial rate against Escherichia coli and Staphylococcus aureus was tested according to GB / T 21866-2008 and calculated over 24 hours. Hydrostatic pressure resistance: Tested according to GB / T 16777-2008, and the maximum hydrostatic pressure value without leakage was recorded; Interlayer peel strength: Tested according to GB / T 2790-1995, the average peel strength between the functional layer and the adhesive layer, and between the adhesive layer and the substrate layer is tested; Tensile strength retention rate under aging: According to GB / T 18244-2022, the tensile strength before and after aging is tested by heat aging at 120℃ for 72h, and the retention rate is calculated to reflect the durability.

[0039] 3. Data processing: Each sample was tested in parallel three times, and the average value was taken as the final result to ensure data reliability.

[0040] 4. The test results are shown in Table 1 below: Table 1. Test results of Examples 1-5 and comparative examples

[0041] As shown in Table 1, the overall performance of Examples 1-5 is far superior to that of the comparative examples, as detailed below: Superior and long-lasting antibacterial performance: The antibacterial rate of the examples is ≥99.5%, which is much higher than the 85.2% of the comparative example. The core reason is that the examples adopt a composite antibacterial system of "carbon nano dots + aminated nano zinc oxide + Kathon CG". The carbon nano dots generate active oxygen and the nano zinc oxide slowly releases Zn²⁺, forming a dual bactericidal mechanism. In contrast, the comparative example only relies on a single silver ion antibacterial agent, which is prone to uneven antibacterial effect due to silver ion aggregation, and is prone to failure with long-term use.

[0042] The waterproofing and seepage resistance is doubled: the example can withstand hydrostatic pressure of 1.7-1.9 MPa, which is nearly twice that of the comparative example (0.9 MPa). This is due to the nano-silica filling the asphalt voids and the organically modified nano-montmorillonite forming a layered barrier in the example, combined with the improved interfacial bonding force of the silane coupling agent, making the waterproof structure denser; the comparative example relies solely on the base asphalt for waterproofing, and the addition of adhesive powder results in more internal voids and poor seepage resistance.

[0043] Stronger interlayer bonding: The interlayer peel strength of the example is 3.5-3.8 N / mm, which is more than 2.7 times that of the comparative example (1.3 N / mm), effectively preventing interlayer peeling and blistering during construction and use. This advantage stems from the compatibility of SEBS and hot-melt pressure-sensitive adhesive in the bonding layer of the example and the interfacial tackifying effect of acrylic microspheres, while the comparative example lacks a dedicated bonding optimization component and relies solely on the adhesiveness of the asphalt itself, resulting in weak bonding strength.

[0044] More reliable aging resistance: The thermal aging strength retention rate of the example is ≥90.8%, which is much higher than the 68.3% of the comparative example. Because the example adds hindered phenolic antioxidants, combined with the UV protection of aminated nano zinc oxide, it forms a full-cycle anti-aging protection; the comparative example has no anti-aging design, and the asphalt molecules are prone to breakage at high temperatures, resulting in rapid performance degradation.

[0045] Through scientific component design, this invention enables the sample to achieve systematic advantages in antibacterial, waterproof, interlayer bonding and aging resistance, solving the problems of single performance and poor reliability of comparative samples, and making it suitable for complex application scenarios such as humid and high-bacteria environments.

[0046] According to another aspect of the invention, such as Figure 1 As shown, a method for preparing a carbon nanoparticle-based antibacterial and waterproof membrane is provided, comprising the following steps: S1. Weigh the raw materials for the waterproof and antibacterial functional layer according to the predetermined mass proportions, mix carbon nanoparticles, aminated nano zinc oxide, nano silica with the dispersant, and form a nanoparticle dispersion by high-speed shearing and stirring. Then, dilute the silane coupling agent with deionized water, adjust the pH, and stir to activate it. Specifically, this includes: Nanoparticle pre-dispersion: Add the prescribed amounts of carbon nanoparticles, aminated nano zinc oxide, and nano silica to a mixing tank, then add a dispersant, preferably fatty alcohol polyoxyethylene ether. Start high-speed shear stirring at 2000-2500 r / min and 60-80℃ for 30-40 min to form a uniform nanoparticle dispersion for later use to prevent agglomeration when mixed with asphalt.

[0047] Activation of silane coupling agent: Add silane coupling agent (preferably aminopropyltriethoxysilane) to a beaker, add deionized water (5-10 times the mass of coupling agent), adjust the pH to 6-7, stir at room temperature for 15-20 minutes to fully hydrolyze and activate the coupling agent, and set aside to improve the reaction efficiency with the surface groups of nanoparticles.

[0048] S2. Add the molten SBS modified asphalt to a high-speed mixer, then add the activated silane coupling agent and nanoparticle dispersion in sequence and stir evenly. Then add the antioxidant, mildew inhibitor and light calcium carbonate in sequence and stir evenly to obtain a waterproof and antibacterial functional layer slurry. Specifically, first, SBS modified asphalt is added to an asphalt melting tank and melted at a constant temperature of 180-200℃, stirred for 30-40 minutes at a speed of 500-800 r / min, until the asphalt is free of obvious particles and has uniform fluidity, then set aside. Next, the molten SBS modified asphalt is pumped into a high-speed mixer, maintaining a temperature of 180-190℃. The activated silane coupling agent is added first, and stirred for 10-15 minutes to allow the silane coupling agent to initially compatibility with the asphalt. Then, the nanoparticle dispersion is slowly added while stirring, with the speed increased to 1500-1800 r / min. Stir at 1500 r / min for 40-50 min to ensure that the nanoparticles are uniformly dispersed in the asphalt. This can be detected by a laser particle size analyzer. If the dispersed particle size of the nanoparticles is ≤50nm, it is considered qualified. Finally, add antioxidant (preferably hindered phenolic antioxidant), mildew inhibitor (preferably Kathon CG), and light calcium carbonate to the mixer in sequence. Maintain the temperature at 180-190℃ and the speed at 1500 r / min, and continue stirring for 25-30 min to form a waterproof and antibacterial functional layer slurry. Take a sample to observe that there is no stratification or sedimentation. Set aside for later use. If there is sedimentation, stir for another 5-10 min.

[0049] S3. Weigh the raw materials of the adhesive layer in the preset mass proportions, add the hot melt pressure-sensitive adhesive, thermoplastic elastomer and softener to the mixing tank, and melt and stir at the preset temperature until the thermoplastic elastomer is dissolved. Then add the tackifying resin, polymer microspheres, organic modified nano montmorillonite, light calcium carbonate and antioxidant and stir evenly to obtain the adhesive layer slurry. Specifically, first, hot melt pressure-sensitive adhesive (SIS), thermoplastic elastomer (preferably SEBS), and softener (preferably naphthenic oil) are added to a special mixing tank for the adhesive layer. The mixture is melted at a constant temperature of 150-170℃ and stirred for 20-25 minutes at a speed of 800-1000 rpm until the elastomer is completely dissolved. Then, tackifying resin (preferably rosin glycerol ester), polymer microspheres (preferably acrylate microspheres with a particle size of 8-12 μm), organic modified nano-montmorillonite, light calcium carbonate, and antioxidant are added to the mixing tank. The temperature is maintained at 150-160℃ and the speed is 1200 rpm, and the mixture is stirred for 30-35 minutes to form an adhesive layer slurry. The slurry should be kept fluid to avoid solidification upon cooling.

[0050] S4. The polyester nonwoven fabric substrate layer is laid flat on the coating machine conveyor belt. The adhesive layer slurry is first coated and then pre-cured in the preheating channel. The waterproof and antibacterial functional layer slurry is then coated and fed into the composite pressure roller for pressing and bonding. The composite roll is then sent to the cooling conveyor belt for air cooling to room temperature and cut according to the preset specifications to obtain carbon nanoparticle-based antibacterial and waterproof roll. Specifically, firstly, the polyester nonwoven fabric substrate layer is laid flat on the coating machine conveyor belt. The conveyor belt speed is adjusted to 1-1.5 m / min to match the coating efficiency. The adhesive layer slurry is evenly coated onto the upper surface of the nonwoven fabric through the first set of coating rollers. The coating thickness is controlled to 0.5-1 mm by adjusting the gap between the coating rollers. Then, it is sent into the preheating channel at a temperature of 150-160℃ for 5-8 minutes to allow the adhesive layer to initially cure, i.e., it is not sticky but still tacky. Next, after the adhesive layer has initially cured, the conveyor belt sends the substrate-adhesive layer composite to the second set of coating rollers, where a waterproof and antibacterial functional layer slurry is coated onto the upper surface of the adhesive layer. The coating thickness is controlled to 2-3 mm to ensure sufficient waterproof and antibacterial functions. Then, it is sent into the composite pressure rollers at a pressure of 0.3-0.5 MPa and a pressure of 1... The roll is rolled and laminated at 60-170℃ for 3-5 seconds to ensure a tight bond between the functional and adhesive layers, free of bubbles and wrinkles. Next, the laminated roll is sent to a cooling conveyor belt, and the air-cooling system is activated. At room temperature, the air velocity is 3-5 m / s, and the roll is cooled for 20-30 minutes to bring the temperature down to room temperature, ensuring complete curing of each layer to prevent subsequent deformation. Finally, the roll is slit according to product specifications, such as 1m wide and 20m long per roll. The cutting accuracy is controlled within ±2mm to avoid rough edges. After slitting, the roll is neatly wound up using a winding machine, with the winding tension controlled at 50-80N to prevent stretching, deformation, or loosening. The finished roll then undergoes key performance testing to ensure it meets requirements, resulting in a carbon nanoparticle-based antibacterial and waterproof roll.

[0051] The specific requirements are as follows: Appearance: Smooth surface, free of bubbles and cracks, with no delamination between layers; Thickness: Total thickness 3-4mm (functional layer 2-3mm + adhesive layer 0.5-1mm + substrate layer 0.3-0.5mm), deviation ±0.2mm; Antibacterial activity: Antibacterial rate against Escherichia coli and Staphylococcus aureus ≥99% (tested according to GB / T 21866-2008); Water resistance: hydrostatic pressure resistance ≥1.8MPa (tested according to GB / T 19979-2015); Interlayer adhesion: Peel strength between functional layer and adhesive layer, and between adhesive layer and substrate layer ≥3.5N / mm (tested according to GB / T2790-1995).

[0052] In summary, by utilizing the above-mentioned technical solution of the present invention, the carbon nanoparticles and aminated nano-zinc oxide form a composite antibacterial system in the waterproof and antibacterial functional layer of the present invention. The carbon nanoparticles and aminated nano-zinc oxide simultaneously generate reactive oxygen species to destroy bacterial cell membranes, and the aminated nano-zinc oxide slowly releases Zn²⁺ to inhibit microbial metabolism. Combined with highly efficient antifungal agents such as Kathon CG, it achieves broad-spectrum inhibition against common pathogenic bacteria such as Escherichia coli and Staphylococcus aureus, as well as molds such as Aspergillus niger and Penicillium. This effectively improves the antibacterial performance of the waterproof membrane, and the antibacterial component is well compatible with the SBS modified bitumen matrix, thus maintaining excellent waterproof performance while improving the antibacterial performance of the waterproof membrane.

[0053] Furthermore, this invention can effectively solve the problem of nanoparticle agglomeration by forming chemical bonds between the functional groups activated by the hydrolysis of silane coupling agents and the surface groups of carbon nanoparticles, aminated nano zinc oxide, and nano silica, combined with the physical dispersion effect of dispersants such as fatty alcohol polyoxyethylene ether. This allows uniformly dispersed nanoparticles to synergistically fill the voids in the asphalt matrix with light calcium carbonate, enhancing the structural density of the functional layer. As a result, it can improve the waterproof and seepage-proof performance while enhancing the tensile strength and abrasion resistance of the waterproof membrane.

[0054] Furthermore, the adhesive layer of this invention is made by blending hot melt pressure-sensitive adhesive with thermoplastic elastomer, and is combined with tackifying resin and softener to adjust the balance between viscosity and flexibility. It can not only increase the interfacial contact area by forming a micro-protrusion structure on the surface of the adhesive layer through polymer microspheres, but also improve the impermeability through the layered barrier effect of organically modified nano-montmorillonite. The three work together to form a strong chemical and physical bond between the adhesive layer, the waterproof and antibacterial functional layer and the polyester nonwoven fabric substrate layer, effectively improving the interlayer peel strength and avoiding interlayer peeling and blistering.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A carbon nanoparticle-based antibacterial and waterproof membrane, characterized in that, It includes, from top to bottom, a waterproof and antibacterial functional layer, an adhesive layer, and a polyester non-woven fabric substrate layer; The waterproof and antibacterial functional layer is composed of the following raw materials in parts by weight: 82-85 parts of SBS modified asphalt, 1.2-1.8 parts of carbon nanoparticles, 1.0-1.5 parts of aminated nano zinc oxide, 2.5-3.0 parts of nano silica, 0.3-0.5 parts of silane coupling agent, 0.2-0.3 parts of antioxidant, 0.3-0.5 parts of dispersant, 0.1-0.2 parts of mildew inhibitor, and 7.0-10 parts of light calcium carbonate.

2. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 1, characterized in that, The silane coupling agent is any one of aminopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, or methacryloyloxypropyltrimethoxysilane.

3. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 2, characterized in that, The antioxidant is a mixture of hindered phenolic antioxidants and phosphite antioxidants.

4. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 3, characterized in that, The dispersant is any one of fatty alcohol polyoxyethylene ether, sorbitan monooleate, sodium dodecylbenzenesulfonate, or tea saponin.

5. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 4, characterized in that, The antifungal agent is any one of Kathon CG, Bifonazole, or Chlorothalonil.

6. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 5, characterized in that, The adhesive layer is composed of the following parts by weight of raw materials: The composition includes 42-45 parts hot melt pressure-sensitive adhesive, 6.0-8.0 parts thermoplastic elastomer, 10-12 parts tackifying resin, 6.0-7.0 parts softener, 4.0-5.0 parts polymer microspheres, 0.6-0.8 parts organic modified nano-montmorillonite, 18-22 parts light calcium carbonate, and 0.2-0.3 parts antioxidant.

7. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 6, characterized in that, The thermoplastic elastomer is any one of SEBS, EPDM rubber, thermoplastic polyurethane, or polyolefin elastomer.

8. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 7, characterized in that, The softener is any one of naphthenic oil, paraffin oil, dioctyl phthalate, or soybean oil.

9. The carbon nanoparticle-based antibacterial and waterproof membrane according to claim 8, characterized in that, The polymer microspheres are any one of acrylate microspheres, styrene microspheres, polyurethane microspheres, or silicone rubber microspheres.

10. A method for preparing a carbon nanoparticle-based antibacterial and waterproof membrane, used to prepare the carbon nanoparticle-based antibacterial and waterproof membrane as described in claim 9, characterized in that, The preparation method includes the following steps: S1. Weigh the raw materials of the waterproof and antibacterial functional layer in the predetermined mass proportions, mix carbon nanodots, aminated nano zinc oxide, nano silica and dispersant, form nanoparticle dispersion by high-speed shearing and stirring, and dilute the silane coupling agent with deionized water and adjust the pH before stirring and activating. S2. Add the molten SBS modified asphalt to a high-speed mixer, then add the activated silane coupling agent and nanoparticle dispersion in sequence and stir evenly. Then add the antioxidant, mildew inhibitor and light calcium carbonate in sequence and stir evenly to obtain a waterproof and antibacterial functional layer slurry. S3. Weigh the raw materials of the adhesive layer in the preset mass proportions, add the hot melt pressure-sensitive adhesive, thermoplastic elastomer and softener to the mixing tank, and melt and stir at the preset temperature until the thermoplastic elastomer is dissolved. Then add the tackifying resin, polymer microspheres, organic modified nano montmorillonite, light calcium carbonate and antioxidant and stir evenly to obtain the adhesive layer slurry. S4. The polyester nonwoven fabric substrate layer is laid flat on the coating machine conveyor belt. The adhesive layer slurry is first coated and then pre-cured in the preheating channel. The waterproof and antibacterial functional layer slurry is then coated and fed into the composite pressure roller for pressing and bonding. The composite roll is then sent to the cooling conveyor belt for air cooling to room temperature and cut according to the preset specifications to obtain carbon nanoparticle-based antibacterial and waterproof roll.

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