Prefabricated assembly reinforced waterproof material and preparation method thereof

Abstract

This invention relates to the field of tunnel construction technology and discloses a prefabricated, assembled, reinforced waterproof material and its preparation method. The material includes a pre-installed adhesive tape, a non-woven fabric with a napped surface, a self-adhesive layer, and a layered composite waterproof board. The layered composite waterproof board is composed of upper and lower PE waterproof board layers and a middle EVA waterproof board layer. The separately prepared premixed materials are extruded into a three-layer co-extrusion die and cooled to obtain the layered composite waterproof board. A self-adhesive layer is coated on its surface to form a self-adhesive layer, which is then bonded to the un-nafted surface of the non-woven fabric. Finally, the napped surface of the non-woven fabric is physically pressed and bonded to the pre-installed adhesive tape. This invention improves interlayer bonding and prevents material delamination by employing a multi-layered composite structure and using a compatibilizer. The pre-installed adhesive tape and the napped surface of the non-woven fabric form a mechanical interlocking network, eliminating the need for hot-melt welding. The self-adhesive layer is distributed in strips to create venting channels, effectively removing trapped air and preventing delamination.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, specifically to a prefabricated assembled reinforced waterproof material and its preparation method. Background Technology

[0002] With the continuous development of prefabricated buildings and underground engineering, higher requirements are being placed on the comprehensive performance and ease of construction of waterproofing materials. Traditional waterproofing membranes, during long-term service, must simultaneously cope with the settlement and deformation of the underlying structure and the risk of puncture by sharp external objects. Current waterproofing systems are gradually evolving towards prefabrication, environmental friendliness, and assembly, aiming to reduce on-site construction labor intensity and improve the overall quality of waterproofing projects.

[0003] Conventional waterproofing membranes are typically made from a single material, making it difficult to simultaneously meet the dual requirements of high strength and puncture resistance as well as high flexibility and stress buffering. Some materials employing multi-layered composite structures suffer from insufficient interlayer adhesion due to differences in polarity between polymers and a lack of effective interfacial compatibility treatment, making them prone to delamination under stress. Regarding joint overlaps and construction, ordinary waterproofing materials often rely on hot-melt welding or large-area chemical adhesive bonding. Hot-melt welding requires strict on-site temperature control; temperature deviations can easily lead to weld failure or leaks. Chemical adhesives are easily affected by environmental temperature and humidity, causing aging and degradation, resulting in decreased durability of the joints. Furthermore, when waterproofing materials with self-adhesive layers are laminated to the substrate, applying adhesive in a full-coverage manner can trap air inside the material, creating air pockets, leading to localized delamination and uneven stress on the waterproofing layer, thus affecting the overall waterproofing effect.

[0004] In summary, existing waterproofing materials have many limitations in terms of composite material structure, joint overlapping methods, and venting design, making it difficult to meet the high durability and reliability requirements of modern prefabricated engineering. Therefore, providing a prefabricated, reinforced waterproofing material that combines high strength and high flexibility, strong interlayer bonding, reliable overlapping methods, and resistance to delamination is a problem that needs to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a prefabricated assembled reinforced waterproof material and its preparation method, which solves the problem that existing composite waterproof materials are prone to delamination under stress due to insufficient interlayer adhesion caused by polymer polarity differences.

[0006] To address the above problems, the present invention provides the following technical solution:

[0007] This invention provides a prefabricated assembled reinforced waterproof material, comprising pre-installed adhesive tape, non-woven fabric with a napped surface, a self-adhesive layer, and a layered composite waterproof board.

[0008] The layered composite waterproof membrane is composed of PE waterproof membrane layers on the top and bottom sides and EVA waterproof membrane layer in the middle.

[0009] The PE waterproof membrane layer is made of the following raw materials in parts by weight: 40-60 parts linear low-density polyethylene, 30-45 parts bimodal high-density polyethylene, 10-30 parts metallocene polyethylene, 5-8 parts maleic anhydride grafted polyethylene compatibilizer, and 2-5 parts antioxidant.

[0010] The EVA waterproof membrane layer is made of the following raw materials in parts by weight: 25-35 parts linear low-density polyethylene, 25-35 parts bimodal high-density polyethylene, 28-30 parts EVA resin, 10-15 parts metallocene polyethylene, 5-8 parts maleic anhydride grafted polyethylene compatibilizer, and 2-5 parts antioxidant.

[0011] By adopting the above technical solution, and using a layered structure composed of the upper and lower PE waterproof membrane layers and the middle EVA waterproof membrane layer, the high structural strength and excellent puncture resistance of PE material are combined with the good flexibility and stress buffering performance of EVA material. In the formulation system, linear low-density polyethylene and bimodal high-density polyethylene are compounded to ensure the tensile strength and environmental stress cracking resistance of the material base; metallocene polyethylene is introduced, and its narrow molecular weight distribution and uniform comonomer distribution characteristics significantly improve the elongation at break, impact toughness and heat-sealing performance of each layer; maleic anhydride-grafted polyethylene compatibilizer, as a macromolecular coupling agent, uses the polar groups of maleic anhydride to reduce the interfacial tension between non-polar polyethylene and polar EVA resin, promoting high entanglement and interpenetration of macromolecular chain segments at the interface during multilayer co-extrusion, forming effective intermolecular forces, fundamentally avoiding interlayer delamination and peeling of the layered composite waterproof membrane; antioxidants effectively inhibit the thermo-oxidative degradation of polymer chains during high-temperature plasticization and long-term service.

[0012] The combination of pre-installed adhesive tape, non-woven fabric with a napped surface, and self-adhesive layer gives the material a prefabricated, quick-connect capability.

[0013] Preferably, the density of the bimodal high-density polyethylene is 0.938 g / cm³. 3 The melt flow rate is 0.12 g / 10 min, the longitudinal tensile yield strength and transverse tensile yield strength are 20 MPa, the melting point is 129℃, and the Vicat softening temperature is 113℃; the maleic anhydride-grafted polyethylene compatibilizer has a grafting rate of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3 The EVA resin has a VA content of 18.5%-20.4% and a melt flow rate of 2.3-3.1 g / 10 min.

[0014] By adopting the above technical solution, selecting bimodal high-density polyethylene with a specific density and a low melt index can effectively improve the rigidity of the product while maintaining the material's processing fluidity. The maleic anhydride-grafted polyethylene compatibilizer with a specific grafting rate of 0.85% provides a suitable interfacial coupling effect, avoiding the molecular chain cross-linking gel phenomenon caused by excessively high grafting rates or insufficient compatibility caused by excessively low grafting rates. Controlling the content of vinyl acetate (VA) in the EVA resin within the range of 18.5%-20.4% ensures that the EVA waterproof sheet layer maintains sufficient elasticity and low-temperature flexibility while avoiding excessive stickiness due to excessive VA content, thereby ensuring the stability of the co-extrusion molding process.

[0015] Preferably, the pre-installed adhesive tape has Y-shaped shooting hooks distributed on one side of the array, and the effective bonding width of the pre-installed adhesive tape is 70-85 mm; the pre-installed adhesive tape is mechanically interlocked and anchored to the pile of the non-woven fabric with pile side through the Y-shaped shooting hooks.

[0016] Preferably, the height of the Y-shaped shooting hook is not less than 1.5 mm, and the shooting hook density is not less than 20 hooks / cm³. 2 .

[0017] Preferably, the pile height of the napped surface is not less than 1.5 mm.

[0018] By adopting the above technical solution, the three-dimensional mechanical interlocking network formed by the Y-shaped injection hook and the pile of the napped surface exhibits high peel strength and shear resistance. Compared with traditional chemical adhesive bonding, the purely physical mechanical interlocking mechanism is unaffected by fluctuations in ambient temperature and humidity, as well as the aging and degradation of polymer colloids, ensuring the long-term reliability and durability of the connection strength of the assembled joint parts.

[0019] Preferably, the non-pilled side of the nonwoven fabric with a piled surface is laminated with a PE film layer; the self-adhesive layer is distributed in strips and coated between the layered composite waterproof board and the PE film layer.

[0020] By adopting the above technical solution, the PE film layer, as a dense, water-blocking interface, can effectively prevent the self-adhesive layer from excessively penetrating into the inner layer of the non-woven fabric with a napped surface during hot-pressing lamination, preventing adhesive loss and avoiding affecting the mechanical anchoring performance of the outer side of the non-woven fabric with a napped surface; the strip-shaped self-adhesive layer not only reduces the overall amount of adhesive and the weight of the material, but more importantly, it constructs a connected micro-venting channel between the waterproof material and the substrate, effectively eliminating the air trapped during construction and avoiding localized blistering and bonding failure caused by internal air pockets.

[0021] Preferably, the self-adhesive layer is made of hot melt pressure-sensitive adhesive, the width of the self-adhesive layer is 80-100 mm, and the center-to-center distance between two adjacent self-adhesive layers is 900-1000 mm.

[0022] By adopting the above technical solution, the width and center-to-center spacing of the self-adhesive layer are controlled within the above range. Under the premise of ensuring that the layered composite waterproof board has sufficient anti-peel bonding strength with the base layer or adjacent roll material, the venting cross-sectional area is increased and the distribution is made more uniform. This ensures that the structure is subjected to uniform stress after assembly and avoids stress concentration.

[0023] This invention also provides a method for preparing a prefabricated reinforced waterproof material, comprising the following steps:

[0024] Weigh linear low-density polyethylene, bimodal high-density polyethylene, metallocene polyethylene, maleic anhydride grafted polyethylene compatibilizer and antioxidant and put them into a high-speed mixer and mix them evenly to obtain PE waterproof board layer premix.

[0025] Weigh linear low-density polyethylene, bimodal high-density polyethylene, EVA resin, metallocene polyethylene, maleic anhydride grafted polyethylene compatibilizer and antioxidant, add them to a high-speed mixer and mix evenly to obtain EVA waterproof board layer premix.

[0026] The PE waterproof board layer premix and the EVA waterproof board layer premix are respectively fed into the first silo and the second silo, heated and plasticized by two parallel single screw extruders, and then pushed into the three-layer co-extrusion die head for extrusion molding and cooling to obtain a layered composite waterproof board.

[0027] Self-adhesive is coated onto the surface of the layered composite waterproof membrane to form a self-adhesive layer, and the self-adhesive layer is bonded to the un-pilled side of the non-woven fabric with a piled surface, and then cut to obtain the intermediate body of the composite waterproof membrane.

[0028] The napped surface of the nonwoven fabric with a napped surface on the outer side of the composite waterproof membrane intermediate body is physically pressed and bonded to the pre-installed adhesive tape to obtain a prefabricated assembled reinforced waterproof material.

[0029] By adopting the above technical solution, the one-time co-extrusion molding process, which involves preparing premixed materials separately and using two parallel single-screw extruders combined with the three-layer co-extrusion die head, avoids the defects of interlayer air entrapment, contamination, and weak interfacial bonding that are easily caused by traditional multiple coating or hot-pressing composite processes. Within the three-layer co-extrusion die head, multiple high-temperature melts are layered and merged under pressure, and similar polymer chains undergo cross-interfacial diffusion and deep entanglement under thermal motion, achieving intrinsic fusion between polymer interfaces. Subsequently, the layered composite waterproof membrane is coated with self-adhesive, hot-pressed, and physically anchored, creating a highly automated and continuous production process.

[0030] Preferably, before preparing the EVA waterproof sheet premix, the EVA resin is pretreated by placing it in an environment with a temperature of 55-70°C and drying it by blowing air for 1.5-3.0 h.

[0031] By adopting the above technical solution, and taking advantage of the hygroscopic physical property of the polar groups of EVA resin, the medium-temperature forced-air drying in advance can fully remove the free moisture inside the resin particles, effectively avoiding the generation of internal bubbles or surface silver streaks due to the rapid vaporization and expansion of moisture during the subsequent high-temperature screw plasticizing extrusion process. This ensures the high density and excellent mechanical properties of the EVA waterproof sheet layer.

[0032] Preferably, during the preparation of the PE waterproof premix and the EVA waterproof premix, the rotation speed of the high-speed mixer is controlled at 400-600 r / min, and the mixing time is controlled at 8-15 min.

[0033] By adopting the above technical solution, the set rotation speed and time parameters enable various matrix resin granules, the antioxidant and the maleic anhydride grafted polyethylene compatibilizer to achieve full physical dispersion under the combined action of high shear and high frictional heat, avoiding local component enrichment or absence caused by uneven mixing, ensuring the microscopic uniformity of the extruded melt, and thus ensuring the stability of the mechanical properties of the final product.

[0034] Preferably, in the process of obtaining the layered composite waterproof membrane: the length-to-diameter ratio of the two parallel single-screw extruders is 30, and the two parallel single-screw extruders include a first screw extruder and a second screw extruder; the molten material in the first hopper enters the upper feed channel and the lower feed channel of the three-layer co-extrusion die head, and the molten material in the second hopper enters the middle feed channel of the three-layer co-extrusion die head; the flow rate ratio of the molten material in the first hopper to the second hopper is controlled to be (1.5-2):1.

[0035] The temperatures of the first screw extruder are set as follows: feed section 165-175℃, compression section 185-200℃, homogenization section 210-220℃, and runner 203-208℃; the temperatures of the second screw extruder are set as follows: feed section 160-170℃, compression section 175-190℃, homogenization section 205-215℃, and runner 198-203℃; the extrusion die temperature is controlled at 200-205℃, and the cooling roller temperature is controlled at 45-60℃.

[0036] By adopting the above technical solution, the extrusion flow ratio is controlled at (1.5-2):1, ensuring that the thickness ratio of the upper and lower PE waterproof sheet layers and the middle EVA waterproof sheet layer reaches a suitable mechanical matching state. Different gradient temperature parameters are set for the first screw extruder and the second screw extruder with an aspect ratio of 30, respectively matching the thermorheological characteristics of the PE main mixture system and the mixture system containing polar EVA, so that the two reach similar melt viscosities before entering the three-layer co-extrusion die head, avoiding melt fracture or interlayer thickness fluctuations caused by viscosity differences at the interface. The specifically controlled die temperature and cooling roller temperature promote rapid and uniform cooling and shaping of the high-temperature co-extruded film after extrusion, effectively inhibiting the excessive growth of polyethylene macromolecular spherulites, thereby optimizing the transparency and low-temperature toughness of the waterproof sheet.

[0037] Preferably, during the process of obtaining the composite waterproof membrane intermediate, before coating the self-adhesive layer, the self-adhesive is preheated for 1 hour, and the coating process parameters are controlled as follows: the glue tank temperature is set to 150-175℃, the glue tube temperature is set to 160-170℃, and the glue gun temperature is set to 160-170℃.

[0038] By adopting the above technical solution, the self-adhesive is preheated to fully melt and reach a stable thermodynamic state. The gradient temperature setting parameters ensure that the self-adhesive flows smoothly with low viscosity in the pipeline transportation system, while avoiding thermal degradation and carbonization of the adhesive due to local overheating. This ensures that the self-adhesive has good surface wetting ability and initial peel strength when sprayed onto the surface of the layered composite waterproof board through a glue gun, thereby improving the accuracy and reliability of the composite operation.

[0039] This invention provides a prefabricated assembled reinforced waterproof material and its preparation method, which has the following beneficial effects:

[0040] 1. This invention employs a layered composite waterproofing board composed of upper and lower PE waterproofing layers and a middle EVA waterproofing layer. Bimodal high-density polyethylene, metallocene polyethylene, and maleic anhydride-grafted polyethylene compatibilizer are incorporated into the raw materials. The layered structure retains the high tensile strength and puncture resistance of the PE waterproofing layer while leveraging the good flexibility and stress buffering properties of the EVA waterproofing layer. Furthermore, the maleic anhydride-grafted polyethylene compatibilizer improves the compatibility between non-polar polyethylene and polar EVA resin, enhancing interlayer bonding. This prevents delamination and peeling of prefabricated reinforced waterproofing materials during use.

[0041] 2. This invention uses pre-installed adhesive tape and non-woven fabric with a napped surface. The pre-installed adhesive tape, which has Y-shaped hooks distributed on one side, is anchored to the napped surface of the non-woven fabric through the Y-shaped hooks, forming a mechanical interlocking network. This physical anchoring connection method eliminates the traditional hot-melt welding process to avoid the risk of weak welding or weld leakage. At the same time, it avoids the defects of chemical adhesives that are easy to age and degrade, thereby improving the reliability and long-term durability of prefabricated reinforced waterproof materials at prefabricated joints.

[0042] 3. This invention distributes self-adhesive layers in strips and coats them between the layered composite waterproof board and the PE film layer. By utilizing the center-to-center distance between two adjacent self-adhesive layers, a connected micro-venting channel is constructed on the composite surface of the waterproof material. During construction and bonding, this strip distribution structure effectively removes air trapped inside the material to avoid localized voids and bonding failures caused by internal air pockets. Ultimately, this ensures that the overall structure of the prefabricated reinforced waterproof material is uniformly stressed after assembly. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the cross-sectional structure of the composite waterproof material of the present invention;

[0044] Figure 2 This is a graph showing the evolution trend of the interface anchoring force retention rate of the composite waterproof material of the present invention.

[0045] Figure 3 This is a diagram showing the longitudinal and transverse tensile stress-strain curves of the composite waterproof material of the present invention.

[0046] Figure 4 This is a diagram showing the puncture load displacement trajectory of the composite waterproof material of the present invention.

[0047] Figure 5 This is a graph showing the evolution of the high-temperature aging T-type peel strength retention rate of the composite waterproof material of the present invention.

[0048] The components include: 1. Pre-installed adhesive tape; 2. Non-woven fabric with a napped surface; 3. Self-adhesive layer; 4. PE waterproof board layer; 5. EVA waterproof board layer. Detailed Implementation

[0049] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0050] See attached document Figure 1The present invention provides a prefabricated assembled reinforced waterproof material, including a pre-installed adhesive tape 1, a non-woven fabric with a napped surface 2, a self-adhesive layer 3, and a layered composite waterproof board.

[0051] The layered composite waterproof board is composed of PE waterproof board layers 4 on the upper and lower sides and EVA waterproof board layer 5 in the middle; the non-woven fabric 2 has a PE film layer on its unpilled side; the self-adhesive layer 3 is distributed in strips and coated between the layered composite waterproof board and the PE film layer; the pre-installed adhesive tape 1 has Y-shaped hooks distributed in a single-sided array, and the pre-installed adhesive tape 1 is connected and anchored to the pile of the non-woven fabric 2 through the Y-shaped hooks to form a mechanical interlocking network.

[0052] The grafting rate of the maleic anhydride-grafted polyethylene compatibilizer involved in this invention was determined and calculated using an acid-base titration method. The specific determination steps and calculation methods are as follows:

[0053] Take a sample of maleic anhydride-grafted polyethylene compatibilizer and place it in a reflux condenser. Add xylene and heat the mixture to reflux at 135℃-140℃ until the sample is completely dissolved. Then pour the high-temperature solution into acetone to precipitate the grafted polymer. Filter the solution and wash the precipitate repeatedly with acetone until the filtrate is neutral after adding phenolphthalein indicator to remove unreacted free maleic anhydride. Place the purified product after washing in a vacuum drying oven and dry it to constant weight.

[0054] Accurately weigh the purified and dried sample and record the mass as m, in g; add the purified sample back into xylene and heat until completely dissolved, add phenolphthalein indicator, and titrate with potassium hydroxide ethanol standard solution while maintaining the solution temperature at 110℃-120℃. The titration endpoint is reached when the solution turns slightly red and does not fade for 30 seconds.

[0055] The grafting rate is calculated using the formula: Grafting rate = (C × V × 98.06) / (2000 × m) × 100%.

[0056] In the formula, C is the concentration of potassium hydroxide ethanol standard solution, in mol / L; V is the volume of potassium hydroxide ethanol standard solution consumed in the titration, in mL; m is the mass of the purified and dried sample, in g; and 98.06 is the molar mass of maleic anhydride, in g / mol.

[0057] Preparation Example 1:

[0058] This preparation example provides a composite waterproof membrane intermediate, which is prepared through the following steps:

[0059] First, during production, two parallel single-screw extruders, each with a length-to-diameter ratio of 30, are used. The prepared PE waterproof board layer 4 premix and EVA waterproof board layer 5 premix are fed into the first and second hoppers, respectively, with the mixing time in each hopper controlled at 5 minutes. The PE waterproof board layer 4 premix is ​​heated and plasticized by the first screw extruder, while the EVA waterproof board layer 5 premix is ​​heated by the second screw extruder. The extruders use screw rotation to push the plasticized molten material into the three-layer co-extrusion die head. The molten material from the first hopper enters the feed channel and lower feed channel of the die head, while the molten material from the second hopper enters the middle feed channel of the die head. The flow rate ratio of the molten material from the first hopper to the second hopper is controlled at 1.5:1. The temperatures of each section of the first screw extruder are set as follows: feed section 175℃, compression section 200℃, homogenization section 220℃, and runner 208℃; the temperatures of each section of the second screw extruder are set as follows: feed section 170℃, compression section 190℃, homogenization section 215℃, and runner 203℃. The PE waterproof layer 4 premix and the EVA waterproof layer 5 premix are compounded in the die head confluence area and then extruded through a die head orifice at 205℃ to form a layered composite waterproof sheet, which is then cooled and shaped by cooling rollers at 60℃.

[0060] Secondly, the self-adhesive is preheated for 1 hour, with the glue tank temperature set to 175℃, the glue hose temperature set to 170℃, and the glue gun temperature set to 170℃. After the layered composite waterproof sheet passes through the cooling rollers, a self-adhesive layer 3 is coated on the surface. The self-adhesive layer 3 has a width of 80 mm, a thickness of 0.5 mm, and a center-to-center distance of 950 mm between two adjacent self-adhesive layers 3. The layered composite waterproof sheet with the self-adhesive coating is then bonded to the non-woven fabric 2 with a PE film layer. The unpilled side of the non-woven fabric 2 is pre-treated with a hot-press bond to the PE film layer. The bonded material is then conveyed to the cutting station by multiple guide rollers and traction rollers for cutting to obtain the intermediate composite waterproof roll material.

[0061] Preparation Example 2:

[0062] This preparation example provides a composite waterproof membrane intermediate, which is prepared through the following steps:

[0063] First, during production, two parallel single-screw extruders, each with a length-to-diameter ratio of 30, are used. The prepared PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are fed into the first and second hoppers, respectively, with the mixing time in each hopper controlled at 10 minutes. The PE waterproof sheet layer 4 premix is ​​heated and plasticized in the first screw extruder, while the EVA waterproof sheet layer 5 premix is ​​heated in the second screw extruder. The extruders use screw rotation to push the plasticized molten material into the three-layer co-extrusion die head. The molten material from the first hopper enters the feed channel and lower feed channel of the die head, while the molten material from the second hopper enters the middle feed channel of the die head. The flow rate ratio of the molten material from the first hopper to the second hopper is controlled at 2:1. The temperatures of each section of the first screw extruder are set as follows: feeding section 165℃, compression section 185℃, homogenization section 210℃, and runner 203℃; the temperatures of each section of the second screw extruder are set as follows: feeding section 160℃, compression section 175℃, homogenization section 205℃, and runner 198℃. The PE waterproof sheet layer 4 premix and the EVA waterproof sheet layer 5 premix are compounded in the die head confluence area and then extruded through a die head orifice at 200℃ to form a layered composite waterproof sheet, which is then cooled and shaped by cooling rollers at 45℃.

[0064] Secondly, the self-adhesive is preheated for 1 hour, with the glue tank temperature set to 150℃, the glue hose temperature set to 160℃, and the glue gun temperature set to 160℃. After the layered composite waterproof membrane passes through the cooling rollers, a self-adhesive layer 3 is coated on the surface. The self-adhesive layer 3 has a width of 100 mm and a thickness of 0.8 mm, with a center-to-center distance of 900 mm between adjacent self-adhesive layers 3. The layered composite waterproof membrane with the self-adhesive coating is then conveyed by guide rollers and bonded to the non-woven fabric 2 with a PE film layer. The unpilled side of the non-woven fabric 2 is pre-treated with a hot-press bond to the PE film layer. The bonded material is then conveyed to the cutting station by multiple guide rollers and traction rollers for cutting to obtain the intermediate composite waterproof membrane.

[0065] Preparation Example 3:

[0066] This preparation example provides a composite waterproof membrane intermediate, which is prepared through the following steps:

[0067] First, during production, two parallel single-screw extruders, each with a length-to-diameter ratio of 30, are used. The prepared PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are fed into the first and second hoppers, respectively, with the mixing time in each hopper controlled at 7 minutes. The PE waterproof sheet layer 4 premix is ​​heated and plasticized in the first screw extruder, while the EVA waterproof sheet layer 5 premix is ​​heated in the second screw extruder. The extruders use screw rotation to push the plasticized molten material into the three-layer co-extrusion die head. The molten material from the first hopper enters the feed channel and lower feed channel of the die head, while the molten material from the second hopper enters the middle feed channel of the die head. The flow rate ratio of the molten material from the first hopper to the second hopper is controlled at 1.8:1. The temperatures of each section of the first screw extruder are set as follows: feeding section 170℃, compression section 190℃, homogenization section 213℃, and runner 205℃; the temperatures of each section of the second screw extruder are set as follows: feeding section 165℃, compression section 180℃, homogenization section 208℃, and runner 200℃. After the PE waterproof sheet layer 4 premix and the EVA waterproof sheet layer 5 premix are compounded in the die head confluence area, they are extruded through a die head orifice at 202℃ to form a layered composite waterproof sheet, which is then cooled and shaped by cooling rollers at 50℃.

[0068] Secondly, the self-adhesive is preheated for 1 hour, with the glue tank temperature set to 160℃, the glue hose temperature set to 165℃, and the glue gun temperature set to 165℃. After the layered composite waterproof membrane passes through the cooling rollers, a self-adhesive layer 3 is coated on the surface. The self-adhesive layer 3 has a width of 90 mm, a thickness of 1.0 mm, and a center-to-center distance of 1000 mm between adjacent self-adhesive layers 3. The layered composite waterproof membrane with the self-adhesive coating is then conveyed by guide rollers and bonded to a non-woven fabric 2 with a PE film layer. The unpilled side of the non-woven fabric 2 is pre-treated with a hot-press bond to the PE film layer. The bonded material is then conveyed to the cutting station by multiple guide rollers and traction rollers for cutting to obtain the intermediate composite waterproof membrane.

[0069] Preparation Example 4:

[0070] This preparation example provides a composite waterproof membrane intermediate, which is prepared through the following steps:

[0071] First, during production, two parallel single-screw extruders, each with a length-to-diameter ratio of 30, are used. The prepared PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are fed into the first and second hoppers, respectively, with the mixing time in each hopper controlled at 8 minutes. The PE waterproof sheet layer 4 premix is ​​heated and plasticized in the first screw extruder, while the EVA waterproof sheet layer 5 premix is ​​heated in the second screw extruder. The extruders use screw rotation to push the plasticized molten material into the three-layer co-extrusion die head. The molten material from the first hopper enters the feed channel and lower feed channel of the die head, while the molten material from the second hopper enters the middle feed channel of the die head. The flow rate ratio of the molten material from the first hopper to the second hopper is controlled at 1.7:1. The temperatures of each section of the first screw extruder are set as follows: feed section 172℃, compression section 195℃, homogenization section 217℃, and runner 206℃; the temperatures of each section of the second screw extruder are set as follows: feed section 167℃, compression section 185℃, homogenization section 210℃, and runner 202℃. After the PE waterproof sheet layer 4 premix and the EVA waterproof sheet layer 5 premix are compounded in the die head confluence area, they are extruded through a die head orifice at 204℃ to form a layered composite waterproof sheet, which is then cooled and shaped by cooling rollers at 55℃.

[0072] Secondly, the self-adhesive is preheated for 1 hour, with the glue tank temperature set to 165℃, the glue hose temperature set to 168℃, and the glue gun temperature set to 168℃. After the layered composite waterproof membrane passes through the cooling rollers, a self-adhesive layer 3 is coated on its surface. The self-adhesive layer 3 has a width of 90 mm, a thickness of 1.2 mm, and a center-to-center distance of 950 mm between adjacent self-adhesive layers 3. The layered composite waterproof membrane with the self-adhesive coating is then conveyed by guide rollers and bonded to a non-woven fabric 2 with a PE film layer. The unpilled side of the non-woven fabric 2 is pre-treated with a hot-press bond to the PE film layer. The bonded material is then conveyed to the cutting station by multiple guide rollers and traction rollers for cutting to obtain the intermediate composite waterproof membrane.

[0073] Example 1:

[0074] This embodiment provides a method for preparing a prefabricated, assembled, reinforced waterproof material, including the following steps:

[0075] S01. Weigh 60 parts by weight of linear low-density polyethylene with a melt flow rate of 2.0 g / 10 min and 40 parts by weight of polyethylene with a density of 0.938 g / cm³. 3 The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 10 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 7 parts by weight of a grafted polyethylene with a grafting rate of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3Maleic anhydride grafted polyethylene compatibilizer and 3 parts by weight antioxidant; put the weighed raw materials into a high-speed mixer and mix for 8 minutes at a speed of 400 r / min to obtain PE waterproof board layer 4 premix.

[0076] S02. Pre-dry the EVA resin in a 55℃ environment for 1.5 h; weigh 35 parts by weight of linear low-density polyethylene with a melt flow rate of 2.0 g / 10 min and 25 parts by weight of [unclear - possibly a specific material or product] with a density of 0.938 g / cm³. 3 The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 28 parts by weight of dried EVA resin with a VA content of 20.4% and a melt flow rate of 3.1 g / 10 min, 13 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 5 parts by weight of grafted polyethylene with a melt flow rate of 2.0 g / 10 min and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 3 parts by weight antioxidant; weigh all raw materials together and put them into a high-speed mixer, mix for 8 minutes at a speed of 400 r / min to obtain EVA waterproof board layer 5 premix.

[0077] S03. The PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are added to the first silo and the second silo respectively, and composite extrusion and coating composite processing are carried out using the method provided in Preparation Example 1 to obtain the composite waterproof membrane intermediate.

[0078] S04. Provide a pre-installed adhesive tape 1 with Y-shaped hooks distributed in a single-sided array. The effective adhesive width of the pre-installed adhesive tape 1 is 85 mm, the height of the Y-shaped hooks is 1.5 mm, and the hook density is 20 hooks / cm². 2 The non-woven fabric 2 on the outer side of the composite waterproof membrane middle body is physically pressed and bonded to the side of the pre-installed adhesive tape 1 with Y-shaped hooks. The pressing pressure is 0.3 MPa, the pressing time is 20 s per meter length, and the pile height of the piled surface is 1.5 mm. This causes the Y-shaped hooks to hook and anchor the pile on the surface of the non-woven fabric 2, thus producing a prefabricated assembled reinforced waterproof material.

[0079] Example 2:

[0080] This embodiment provides a method for preparing a prefabricated, assembled, reinforced waterproof material, including the following steps:

[0081] S01. Weigh 50 parts by weight of linear low-density polyethylene with a melt flow rate of 1.5 g / 10 min and 30 parts by weight of polyethylene with a density of 0.938 g / cm³. 3The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 30 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 8 parts by weight of a grafted polyethylene with a grafting rate of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 5 parts by weight antioxidant; put the weighed raw materials into a high-speed mixer and mix for 10 min at a speed of 500 r / min to obtain PE waterproof board layer 4 premix.

[0082] S02. The EVA resin was pre-dried at 60℃ for 2.0 h using forced air drying; 30 parts by weight of linear low-density polyethylene with a melt flow rate of 1.5 g / 10 min and 33 parts by weight of [unclear - possibly a specific type of polyethylene] with a density of 0.938 g / cm³ were weighed. 3 The composition includes: bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min; 29 parts by weight of dried EVA resin with a VA content of 18.5% and a melt flow rate of 2.3 g / 10 min; 10 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min; and 8 parts by weight of grafted polyethylene with a melt flow rate of 2.0 g / 10 min and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 2 parts by weight of antioxidant; put all the weighed raw materials into a high-speed mixer and mix for 10 min at a speed of 500 r / min to obtain EVA waterproof board layer 5 premix.

[0083] S03. The PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are added to the first silo and the second silo respectively, and composite extrusion and coating composite processing are carried out using the method provided in Preparation Example 2 to obtain the composite waterproof membrane intermediate.

[0084] S04. A pre-installed adhesive tape 1 with Y-shaped hooks arranged in a single-sided array is provided. The effective adhesive width of the pre-installed adhesive tape 1 is 70 mm; the height of the Y-shaped hooks is 2.0 mm; and the hook density is 25 hooks / cm². 2 The non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body is physically pressed and bonded to the side of the pre-installed adhesive tape 1 with Y-shaped hooks. The pressing pressure is 0.5 MPa, the pressing time is 10 s per meter length, and the pile height of the piled surface is 2.0 mm. The non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body is physically pressed and bonded to the side of the pre-installed adhesive tape 1 with Y-shaped hooks, so that the Y-shaped hooks and the pile on the surface of the non-woven fabric 2 are hooked and anchored to each other, thus producing a prefabricated assembled reinforced waterproof material.

[0085] Example 3:

[0086] This embodiment provides a method for preparing a prefabricated, assembled, reinforced waterproof material, including the following steps:

[0087] S01. Weigh 55 parts by weight of linear low-density polyethylene with a melt flow rate of 1.7 g / 10 min and 35 parts by weight of polyethylene with a density of 0.938 g / cm³. 3 The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 15 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 5 parts by weight of a grafted polyethylene with a graft ratio of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 2 parts by weight of antioxidant; put the weighed raw materials into a high-speed mixer and mix for 12 min at a speed of 450 r / min to obtain PE waterproof board layer 4 premix.

[0088] S02. The EVA resin was pre-dried at 65℃ for 2.5 h using forced air drying; 33 parts by weight of linear low-density polyethylene with a melt flow rate of 1.7 g / 10 min and 35 parts by weight of [unclear - possibly a specific material or product] with a density of 0.938 g / cm³ were weighed. 3 The composition includes: bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min; 30 parts by weight of dried EVA resin with a VA content of 19.5% and a melt flow rate of 2.8 g / 10 min; 12 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min; and 6 parts by weight of grafted polyethylene with a melt flow rate of 2.0 g / 10 min and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 5 parts by weight of antioxidant; put all the weighed raw materials into a high-speed mixer and mix for 12 minutes at a speed of 450 r / min to obtain EVA waterproof board layer 5 premix.

[0089] S03. The PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are added to the first silo and the second silo respectively, and composite extrusion and coating composite processing are carried out using the method provided in Preparation Example 3 to obtain the composite waterproof membrane intermediate.

[0090] S04. A pre-installed adhesive tape 1 with Y-shaped hooks arranged in a single-sided array is provided. The effective adhesive width of the pre-installed adhesive tape 1 is 80 mm; the height of the Y-shaped hooks is 2.0 mm; and the hook density is 25 hooks / cm². 2The non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body is physically pressed and bonded to the side of the pre-installed adhesive tape 1 with Y-shaped hooks. The pressing pressure is 0.4 MPa, the pressing time is 15 s per meter length, and the pile height of the piled surface is 2.0 mm. The physical pressing and bonding of the non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body with the side of the pre-installed adhesive tape 1 with Y-shaped hooks causes the Y-shaped hooks to hook and anchor to the pile on the surface of the non-woven fabric 2, thus producing a prefabricated assembled reinforced waterproof material.

[0091] Example 4:

[0092] This embodiment provides a method for preparing a prefabricated, assembled, reinforced waterproof material, including the following steps:

[0093] S01. Weigh 40 parts by weight of linear low-density polyethylene with a melt flow rate of 1.8 g / 10 min and 45 parts by weight of polyethylene with a density of 0.938 g / cm³. 3 The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 20 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 5 parts by weight of a grafted polyethylene with a graft ratio of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 3 parts by weight antioxidant; put the weighed raw materials into a high-speed mixer and mix for 15 min at a speed of 600 r / min to obtain PE waterproof board layer 4 premix.

[0094] S02. Pre-dry the EVA resin in a 70℃ environment for 3.0 h using forced air drying; weigh 25 parts by weight of linear low-density polyethylene with a melt flow rate of 1.8 g / 10 min and 35 parts by weight of [unclear - possibly a specific type of polyethylene, but without further context, a precise translation is not possible]. 3 The composition includes bimodal high-density polyethylene with a melt flow rate of 0.12 g / 10 min, 30 parts by weight of dried EVA resin with a VA content of 19.0% and a melt flow rate of 2.5 g / 10 min, 15 parts by weight of metallocene polyethylene with a melt flow rate of 3.5 g / 10 min, and 7 parts by weight of grafted polyethylene with a melt flow rate of 2.0 g / 10 min and a density of 0.924 g / cm³. 3 Maleic anhydride grafted polyethylene compatibilizer and 4 parts by weight of antioxidant; put all the weighed raw materials into a high-speed mixer and mix for 15 min at a speed of 600 r / min to obtain EVA waterproof board layer 5 premix.

[0095] S03. The PE waterproof sheet layer 4 premix and EVA waterproof sheet layer 5 premix are added to the first silo and the second silo respectively, and composite extrusion and coating composite processing are carried out using the method provided in Preparation Example 4 to obtain the composite waterproof membrane intermediate.

[0096] S04. A pre-installed adhesive tape 1 with Y-shaped hooks arranged in a single-sided array is provided. The effective adhesive width of the pre-installed adhesive tape 1 is 75 mm; the height of the Y-shaped hooks is 1.8 mm; and the hook density is 30 hooks / cm². 2 The non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body is physically pressed and bonded to the side of the pre-installed adhesive tape 1 with Y-shaped hooks. The pressing pressure is 0.3 MPa, the pressing time is 20 s per meter length, and the pile height of the piled surface is 1.8 mm. The physical pressing and bonding of the non-woven fabric 2 on the outer side of the composite waterproof membrane intermediate body with the side of the pre-installed adhesive tape 1 with Y-shaped hooks causes the Y-shaped hooks to hook and anchor to the pile on the surface of the non-woven fabric 2, thus producing a prefabricated assembled reinforced waterproof material.

[0097] Comparative Example 1:

[0098] Compared with Example 4, the difference is that the raw materials of the PE waterproof board layer 4 premix and the EVA waterproof board layer 5 premix are both replaced with 100 parts by weight of linear low-density polyethylene, while the other parameters and steps are the same.

[0099] Comparative Example 2:

[0100] Compared with Example 3, the difference is that it does not have a three-layer sandwich structure. The premix of PE waterproof board layer 4 is replaced with a raw material formula that is completely consistent with the premix of EVA waterproof board layer 5, so that the extruded board is a single EVA waterproof board. All other parameters and steps are the same.

[0101] Comparative Example 3:

[0102] Compared with Example 1, the difference is that the bimodal high-density polyethylene in the PE waterproof board layer 4 premix and EVA waterproof board layer 5 premix formulations is replaced with an equal part by weight of ordinary unimodal high-density polyethylene, while the other parameters and steps are the same.

[0103] Test Example 1:

[0104] Tests were conducted on the interface between the napped surface of the waterproof material and the pre-installed adhesive tape 1, including the assembly time required for the initial interface formation, the peel force under normal pull-out of the interface, and the static slip under continuous shear stress.

[0105] Experimental steps:

[0106] Composite waterproof membrane samples were prepared by cutting out samples of each embodiment and comparative example with a length of 200 mm and a width of 50 mm.

[0107] The pre-installed adhesive tape 1 with Y-shaped injection hooks is flattened and fixed to the surface of the stainless steel test substrate using structural adhesive.

[0108] Lay the napped side of the waterproof material sample flat on top of the pre-installed adhesive tape 1. Use a standard pressure roller with a mass of 2 kg to roll back and forth on the sample surface 3 times at a speed of 300 mm / min to complete the physical overlap. Record the average operation time required per square meter of overlap area.

[0109] The substrate was then fixed in the lower fixture of the universal testing machine, and the free end of the sample was clamped in the upper fixture. A continuous peel test was performed along the 180° direction at a tensile rate of 50 mm / min, and the maximum force value was recorded.

[0110] Another sample with the same overlapping structure was vertically suspended, with a standard weight of 500 g suspended at the bottom. The whole sample was placed in a constant temperature and humidity chamber at 25℃ and 60% relative humidity. The relative static load slip of the interface was recorded after 24 hours of continuous loading. The test data are shown in Table 1.

[0111] Table 1 Initial peel force and relative static slip. Group <![CDATA[Actual assembly time s / m 2 > Initial peel force (N / cm) Relative static load slip (mm) Example 1 42.63 5.08 0.35 Example 2 45.17 4.86 0.42 Example 3 41.34 5.31 0.29 Example 4 46.82 4.93 0.38 Comparative Example 1 58.45 3.52 1.15 Comparative Example 2 49.71 5.12 0.88 Comparative Example 3 44.29 4.75 0.51

[0112] As shown in Table 1, the layered sandwich structure of Examples 2 and 3 enables the napped surface to transmit normal stress when the pressure roller is applied, so that the fibers on the surface of the nonwoven fabric 2 and the Y-shaped injection hook of the pre-installed adhesive tape 1 form a stable mechanical interlocking network. The actual assembly time is short and the initial peeling force is maintained at a high level.

[0113] See attached document Figure 2 Examples 3 and 4 enhance interlayer adhesion of the plates through polarity, imparting better structural toughness to the material. The anchoring force retention rates of Examples 3 and 4 remain at a high level, with the curves showing significant stability. Example 4 also possesses the advantages of a multi-layer sandwich structure and compatibilizer modification; its retention rate curve is below that of Example 3 and shows a certain degree of decrease, while its overall durability remains at a good level.

[0114] The multi-layered composite structure and specific polymer blend formulation play a synergistic role in the physical hook-and-loop bonding process. The mechanical interlocking network formed by the napped surface of the outer non-woven fabric 2 and the Y-shaped hooks of the pre-installed adhesive tape 1 provides basic anchoring force, while the core layer containing polar compatibilizer effectively transfers and disperses interfacial stress, avoiding interlayer delamination of the multi-layered structure under tension. This purely physical assembly mode not only avoids the problems of local burn-through and material thermal degradation that are easily caused by traditional hot-melt construction, but also reduces the dependence of joint quality on the construction environment and operators. At the same time, it maintains the interfacial stability of the structure under long-term static shear conditions, effectively ensuring the overall sealing effect and long-term durability of the waterproofing system for underground projects such as tunnels.

[0115] Test Example 2:

[0116] The internal structural uniformity and bidirectional mechanical response of the layered composite waterproof membrane under stress were tested. Comparative tests were conducted on the longitudinal and transverse tensile properties of the material to verify the role of bimodal high-density polyethylene in regulating the polymer crystallization morphology during the extrusion casting process.

[0117] Experimental steps:

[0118] Cut type 1 dumbbell-shaped standard samples along the extrusion direction (longitudinal) and perpendicular to the extrusion direction (transverse).

[0119] All samples were placed in a constant temperature and humidity environment of 23℃ and 50% for 24 hours to condition.

[0120] The two ends of the specimen were then fixed in the upper and lower clamps of the universal testing machine, and the tensile speed was set to 250 mm / min for tensile testing until the specimen broke.

[0121] During the test, the system automatically records the mechanical data of the yield point and the fracture point, and calculates the tensile stress and tensile strain at the fracture of the specimen.

[0122] Five valid samples were tested in both the longitudinal and transverse directions for each group of samples. The arithmetic mean was taken as the test result for this batch of materials, as shown in Table 2.

[0123] Table 2 Comparison of longitudinal and transverse mechanical properties test data Group Longitudinal tensile stress (MPa) Transverse tensile stress (MPa) Longitudinal tensile strain % Transverse tensile strain % Example 1 18.53 18.21 651.4 644.8 Example 2 17.82 17.55 678.9 671.2 Example 3 18.14 18.06 664.2 659.7 Example 4 17.56 17.18 688.5 681.3 Comparative Example 1 15.24 14.86 721.5 708.9 Comparative Example 2 12.51 11.97 848.3 825.6 Comparative Example 3 18.67 13.52 642.1 483.5

[0124] Table 2 shows the test data reflecting the influence of polymer matrix selection on the isotropic mechanical properties of the composite material. The test results of Examples 1 to 4 indicate that the longitudinal and transverse tensile strengths and elongations at break are quite similar, demonstrating a clear bidirectional stress balance in the material. Examples 2 and 3 show transverse tensile strengths of 17.55 MPa and 18.06 MPa, respectively, with minimal difference from the longitudinal strength. This is attributed to the molecular weight distribution structure of bimodal high-density polyethylene. The low molecular weight fraction improves the rheology and dispersion of the melt within the extruder head, while the high molecular weight fraction is distributed at the crystal boundaries during the crystallization stage, promoting the formation of uniformly sized and consistently arranged spherulitic structures within the matrix, thus endowing the sheet with similar tensile strength in all directions.

[0125] See attached document Figure 3 The test results verified the effect of bimodal high-density polyethylene in improving the mechanical isotropy of the composite material. Its wide molecular weight distribution characteristics regulate the orientation and crystallization kinetics of polymer chains during the extrusion casting stage, making the internal crystalline region distribution more uniform and suppressing the structural orientation that is easily generated by unimodal polyethylene. In practical engineering applications, this balance of longitudinal and transverse mechanical properties can effectively resist multi-directional tensile deformation under uneven settlement of the substrate or complex stress conditions, avoiding directional tearing failure of traditional waterproof membranes due to insufficient transverse tensile strength, and improving the structural safety and deformation adaptability of the waterproof layer under complex stress conditions.

[0126] Test Example 3:

[0127] The puncture strength test was conducted according to the test method in TB / T 3360.1-2023 (Railway Tunnel Waterproofing and Drainage Materials Part 1: Waterproofing Boards and Drainage Boards); and the test was conducted according to the test method in GB 529-2008 (Determination of Tear Strength of Vulcanized Rubber or Thermoplastic Rubber) without cut right angles. The results are shown in Table 3.

[0128] Table 3. Test results of puncture resistance and right-angle tear strength

[0129] Group Puncture resistance N Right-angle tearing force N Example 1 385.42 92.76 Example 2 371.85 89.41 Example 3 412.63 105.38 Example 4 364.27 85.12 Comparative Example 1 245.71 61.84 Comparative Example 2 188.35 42.59 Comparative Example 3 352.18 55.43

[0130] The data in Table 3 reflect the influence of multilayer composite structures and polymer blending on the material's resistance to localized damage. The test data of Examples 1 to 4 are relatively high, showing better resistance to localized damage. This is because of the combination of metallocene polyethylene and bimodal high-density polyethylene. Metallocene polyethylene improves the deformation capability of the polymer matrix, while bimodal high-density polyethylene provides crystalline support. When faced with stress concentration, the multilayer sandwich structure promotes the dissipation of locally concentrated stress to the surrounding areas, increasing the load required for the material to undergo macroscopic fracture.

[0131] See attached document Figure 4Example 3 showed an increase in modulus in the early stage of compression, and then entered the plastic yielding stage. It broke under a puncture load of more than 400 N and a puncture displacement of about 28 mm. The area below the curve was large, which proved that it had a good balance between toughness and rigidity. The energy absorption plateau of Example 4 was slightly lower than that of Example 3, but the overall puncture resistance remained at a reasonable level.

[0132] By optimizing the polymer blending ratio and the thickness distribution of the multi-layer sandwich structure, the material's resistance to localized damage has been enhanced. The high deformation capacity of the matrix provided by metallocene polyethylene and the rigid crystalline support provided by bimodal high-density polyethylene enable the material to quickly redistribute stress when subjected to pressure from sharp objects. It absorbs external destructive energy through localized plastic yielding and has structural characteristics that combine good toughness and reasonable stiffness. It can effectively resist the compression and damage from residual gravel in the tunnel floor or sidewall base layer, reducing the risk of hidden damage to the waterproof material during trolley placement, rebar binding, or subsequent pouring, and preventing tiny puncture points from evolving into penetrating leakage channels under later water pressure.

[0133] Test Example 4:

[0134] The reliability and durability of the waterproof material at the joint were tested. Comparative tests were conducted on the mechanical properties of the overlapping joints to verify the interfacial compatibility and adhesive stability of the compatibilizer and ethylene vinyl acetate copolymer resin under thermal aging conditions, ensuring that the joint can withstand shear stress.

[0135] Referring to the requirements for the peel performance of polymer waterproof membrane joints in the national standard GB / T 328.21-2007 (Test Methods for Building Waterproof Membranes Part 21: Peel Performance of Polymer Waterproof Membranes) and the requirements for the shear performance of polymer waterproof membrane joints in the national standard GB / T 328.23-2007 (Test Methods for Building Waterproof Membranes Part 23: Shear Performance of Polymer Waterproof Membranes), various types of samples were cut, and the intermediate samples of the composite waterproof membrane were pressed and spliced ​​to prepare joint test specimens. All test specimens were left to stand for 48 hours at 23℃ and 50% relative humidity. Subsequently, the specimens were divided into multiple groups. The reference group was tested at room temperature, while the other groups were placed in an aging chamber at 70℃ for 7, 14, 21 and 28 days of continuous aging. After reaching the specified time, the specimens were cooled and restored for 24 hours. The specimens were then stretched at a rate of 100 mm / min along the T-shaped peel direction and the parallel shear direction. The peak force was recorded and the aging retention rate was calculated. The results are shown in Table 4.

[0136] Table 4 Mechanical Data of T-Peel Strength and Overlap Shear Strength Group Room temperature T-type peel strength (N / mm) T-peel strength (N / mm) after 7 days of aging room temperature lap shear strength (MPa) The lap shear strength after 7 days of aging (MPa) Example 1 3.86 3.43 1.28 1.14 Example 2 3.74 3.29 1.19 1.06 Example 3 4.17 3.94 1.45 1.36 Example 4 3.68 3.15 1.16 0.99 Comparative Example 1 2.18 1.06 0.77 0.43 Comparative Example 2 1.91 0.94 0.65 0.36 Comparative Example 3 2.57 1.65 0.89 0.52

[0137] Table 4 shows the influence of the formulation system on the bonding strength of the joint interface. Under normal temperature conditions, the joint mechanical properties of Examples 1-4 are significantly higher than those of the comparative example. Examples 2 and 3 exhibit high T-peel strength and lap shear strength at room temperature. After 7 days of high-temperature aging, Example 3 still maintains a peel strength of 3.94 N / mm, demonstrating good thermal stability and adhesion. This performance is attributed to the compatibilizer and ethylene-vinyl acetate copolymer resin introduced into the system. Since the compatibilizer and resin contain polar groups, they improve the compatibility between polyethylene layers, increasing the intermolecular forces and interfacial adhesion between the waterproof substrate surface and the self-adhesive layer 3. This combination of polar interaction and physical adhesion enhances the joint's resistance to peeling and shearing.

[0138] See attached document Figure 5 The figure shows the retention rate of T-peel strength for each group during the 28-day high-temperature aging period. The solid line marked with a solid circle represents Example 3, and the dashed line marked with a solid square represents Example 4. The retention rate curve of Example 3 remained stable within the aging period. The high T-peel strength retention rate after 28 days of high-temperature aging indicates that the polar adhesion at the material interface has good anti-aging ability, and no significant peeling occurred under high-temperature conditions. The retention rate curve of Example 4 showed a certain decrease, but the overall adhesion performance remained at a good level.

[0139] Experimental data and aging curves together demonstrate that the combination of polar compatibilizer and ethylene vinyl acetate copolymer resin constructs a stable bonding layer at the joint interface. The polar groups not only enhance the interlayer cohesion of the polyolefin substrate itself but also strengthen the interfacial adhesion between it and the self-adhesive layer 3. This interaction remains stable under prolonged high-temperature thermo-oxidative aging conditions, alleviating thermal relaxation of polymer chains and interfacial debonding. This structural design improves upon the problem of edge lifting, cracking, or debonding that easily occurs at the overlap edges of traditional polymer waterproof membranes due to environmental temperature fluctuations, ensuring the sealing effectiveness of prefabricated assembled waterproof joints in long-term service environments.

Claims

1. A prefabricated, assembled, reinforced waterproof material, characterized in that, It includes pre-installed adhesive tape (1), non-woven fabric with a napped surface (2), self-adhesive layer (3), and layered composite waterproof board; The layered composite waterproof membrane is composed of PE waterproof membrane layers (4) on the upper and lower sides and EVA waterproof membrane layer (5) in the middle. The PE waterproof sheet layer (4) is made from the following raw materials in parts by weight: 40-60 parts of linear low-density polyethylene, 30-45 parts of bimodal high-density polyethylene, 10-30 parts of metallocene polyethylene, 5-8 parts of maleic anhydride grafted polyethylene compatibilizer, and 2-5 parts of antioxidant. The EVA waterproof layer (5) is made from the following raw materials in parts by weight: 25-35 parts linear low-density polyethylene, 25-35 parts bimodal high-density polyethylene, 28-30 parts EVA resin, 10-15 parts metallocene polyethylene, 5-8 parts maleic anhydride grafted polyethylene compatibilizer, and 2-5 parts antioxidant.

2. The prefabricated assembled reinforced waterproof material according to claim 1, characterized in that, The density of the bimodal high-density polyethylene is 0.938 g / cm³. 3 The melt flow rate is 0.12 g / 10 min; The maleic anhydride-grafted polyethylene compatibilizer has a grafting rate of 0.85%, a melt flow rate of 2.0 g / 10 min, and a density of 0.924 g / cm³. 3 ; The EVA resin has a VA content of 18.5%-20.4% and a melt flow rate of 2.3-3.1 g / 10 min.

3. The prefabricated assembled reinforced waterproof material according to claim 1, characterized in that, The pre-installed adhesive tape (1) has Y-shaped hooks arranged in a single-sided array, and the effective bonding width of the pre-installed adhesive tape (1) is 70-85 mm; the height of the Y-shaped hooks is not less than 1.5 mm, and the hook density is not less than 20 hooks / cm. 2 The pile height of the piled surface is not less than 1.5mm, and the pre-installed adhesive tape (1) is connected and anchored to the pile of the non-woven fabric (2) through the Y-shaped shooting hook to form a mechanical interlocking network.

4. The prefabricated assembled reinforced waterproof material according to claim 1, characterized in that, The non-woven fabric (2) has a PE film layer on its unpilled side; The self-adhesive layer (3) is distributed in strips and coated between the layered composite waterproof board and the PE film layer.

5. The prefabricated assembled reinforced waterproof material according to claim 4, characterized in that, The width of the self-adhesive layer (3) is 80-100 mm, the coating thickness is 0.5-1.2 mm, and the center-to-center distance between two adjacent self-adhesive layers (3) is 900-1000 mm.

6. The method for preparing the prefabricated assembled reinforced waterproof material according to any one of claims 1-5, characterized in that, Includes the following steps: Weigh linear low-density polyethylene, bimodal high-density polyethylene, metallocene polyethylene, maleic anhydride grafted polyethylene compatibilizer and antioxidant and put them into a high-speed mixer and mix them evenly to obtain PE waterproof board layer (4) premix. Weigh linear low-density polyethylene, bimodal high-density polyethylene, EVA resin, metallocene polyethylene, maleic anhydride grafted polyethylene compatibilizer and antioxidant and put them into a high-speed mixer and mix them evenly to obtain EVA waterproof board layer (5) premix. The PE waterproof board layer (4) premix and the EVA waterproof board layer (5) premix are respectively put into the first silo and the second silo, heated and plasticized by two parallel single screw extruders and then pushed into the three-layer co-extrusion die head, extruded and cooled to obtain the layered composite waterproof board; Self-adhesive is coated on the surface of the layered composite waterproof board to form the self-adhesive layer (3), and the self-adhesive layer (3) is bonded to the unpiled surface of the non-woven fabric (2), and then cut to obtain the intermediate body of the composite waterproof roll. The napped surface of the nonwoven fabric (2) on the outer side of the composite waterproof roll body is physically pressed and bonded to the pre-installed adhesive tape (1) to obtain the prefabricated assembled reinforced waterproof material.

7. The preparation method according to claim 6, characterized in that, Before preparing the EVA waterproof sheet layer (5) premix, the EVA resin is pretreated: The EVA resin was placed in an environment with a temperature of 55-70℃ and dried by forced air for 1.5-3.0 h.

8. The preparation method according to claim 6, characterized in that, During the preparation of the PE waterproof board layer (4) premix and the EVA waterproof board layer (5) premix, the speed of the high-speed mixer is controlled at 400-600 r / min and the mixing time is controlled at 8-15 min.

9. The preparation method according to claim 6, characterized in that, In the process of obtaining the layered composite waterproof membrane: The length-to-diameter ratio of the two parallel single-screw extruders is 30, and the two parallel single-screw extruders include a first screw extruder and a second screw extruder. The molten material in the first hopper enters the upper and lower feed channels of the three-layer co-extrusion die head, and the molten material in the second hopper enters the middle feed channel of the three-layer co-extrusion die head; The ratio of molten material flow rate between the first silo and the second silo is controlled to be (1.5-2):1; The temperature settings of the first screw extruder are as follows: feeding section 165-175℃, compression section 185-200℃, homogenization section 210-220℃, and flow channel 203-208℃. The temperature settings for the second screw extruder are: 160-170℃ for the feeding section, 175-190℃ for the compression section, 205-215℃ for the homogenization section, and 198-203℃ for the flow channel; The extrusion die temperature is set to 200-205℃, and the cooling roller temperature is set to 45-60℃.

10. The preparation method according to claim 6, characterized in that, In the process of obtaining the composite waterproof membrane intermediate, before coating to form the self-adhesive layer (3), the self-adhesive is preheated for 1 hour, and the coating process parameters are controlled as follows: Set the glue tank temperature to 150-175℃, the glue hose temperature to 160-170℃, and the glue gun temperature to 160-170℃.

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