Composite organic asphalt for clean drainage type wing wall impervious wall tooth groove water stop structure and preparation method of composite organic asphalt for clean drainage type wing wall impervious wall tooth groove water stop structure

Abstract

The invention discloses composite organic asphalt for a clean drainage type wing wall diaphragm wall tooth groove water stop structure and a preparation method. The composite organic asphalt comprises the following material components in parts by mass: 56-71.4 parts of natural asphalt; 22-32 parts of a composite modifier; 6-8 parts of naphthenic oil; 0.4 to 0.6 part of a trimethyl phosphate cross-linking agent; wherein the composite modifier is prepared from the following raw materials in parts by mass: 20 to 30 parts of thermoplastic polyurethane elastomer; 55-65 parts of modified natural rubber powder; 2-4 parts of a mixture of a titanate coupling agent and a silane coupling agent; 0.3 to 0.5 part of an organic peroxide cross-linking agent; and 0.5 to 1.0 part of an anti-aging agent. According to the invention, the interface compatibility of the water-stop asphalt and concrete can be greatly improved, so that the impermeability is greatly improved, and the ductility under an extremely low temperature condition is greatly improved. In addition, the problems of high asphalt carbon emission and difficulty in realizing permanent solid waste of a traditional tooth groove water stop structure for the wing wall diaphragm wall can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of waterproof sealing layer construction for newly-built or repaired anti-seepage wall groove structures in the fields of water conservancy, hydropower and transportation infrastructure, in particular to a composite organic asphalt for a clean-drainage wing wall anti-seepage wall groove water-stopping structure and a preparation method thereof. Background Art

[0002] In water conservancy and hydropower projects and transportation infrastructure, the water-stop structure at the connection between the wing wall anti-seepage wall groove and the anti-seepage wall is the core of the entire anti-seepage system. The long-term durability of its waterproof sealing layer is directly related to the safety of the project. Figure 1 As shown, the anti-seepage wall groove 2 is set at the bottom of the wing wall base plate 3, and the water-stopping structure at the connection between the anti-seepage wall groove 2 and the anti-seepage wall 1 includes water-stopping asphalt 4. However, traditional water-stopping asphalt has significant defects in the application of this water-stopping structure: when the project is subjected to high water pressure and repeated changes in ambient temperature for a long time, the material is prone to interface peeling with the matrix, accompanied by micro-cracks expansion, which eventually leads to the failure of the anti-seepage and water-stopping function. Especially in areas with high groundwater levels or frequent freeze-thaw cycles, the anti-seepage wall structure is continuously affected by environmental factors such as frost heave and thaw settlement of the foundation and water level fluctuations, which will cause small deformations, which places extremely high demands on the anti-seepage performance of the water-stopping structure.

[0003] Unfortunately, the existing improved modified asphalt materials are still insufficient in their ability to withstand high water pressure and temperature cycles in the long term, making it difficult to effectively adapt to the anti-seepage performance requirements caused by the environment, which seriously affects the water-stopping effect.

[0004] In addition, the current production process of asphalt materials generally has environmental problems. Traditional preparation methods often require high-temperature heating and complex chemical modification processes, which not only consume a lot of energy, but also release harmful gases such as volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs), as well as produce wastewater and waste residue containing heavy metals, which burden the environment and are contrary to the concept of green construction and sustainable development. At the same time, most of the existing improvement plans focus on improving a single performance (such as only focusing on impermeability or only focusing on low-temperature performance), and lack the coordinated optimization of core requirements such as temperature adaptability, environmental friendliness and impermeability.

[0005] Patent CN118087328A significantly optimizes the structural drainage path and improves water tightness by providing a gap-filling crushed stone layer and a surface water-tight layer, effectively addressing the high water permeability problem of traditional asphalt pavements. However, the patent focuses solely on improving water resistance and fails to address the material's deformation adaptability under temperature fluctuations, such as freeze-thaw cycles or high-temperature softening, or its low-temperature ductility. This suggests that the solution may not substantially improve temperature sensitivity, resulting in reduced asphalt performance in dynamic temperature environments.

[0006] Existing asphalt materials generally use heavy metal catalysts (such as organotin) and high aromatic solvents (such as coal tar), and the VOCs emissions during their production process can reach 120-150 mg / m 3 (GB 37822-2019 limit ≤ 50mg / m 3 ). Although patent CN114876123A introduces waste tire rubber powder to achieve solid waste utilization, the polycyclic aromatic hydrocarbons (PAHs) content in the rubber powder is greater than 8mg / kg (REACH regulatory limit is less than 1mg / kg), posing a risk of soil pollution. CN116134102A uses a high-temperature (180-200℃) mixing process, and carbon emissions per ton of product reach 85kg (the industry's advanced level is ≤60kg). In addition, traditional modified asphalt is difficult to degrade after aging, and landfill treatment accounts for more than 70%, forming permanent solid waste. These environmental defects seriously restrict the sustainable development of the industry.

[0007] Therefore, there is an urgent need for a new asphalt material and a preparation method thereof that has excellent performance, is environmentally friendly and has stronger adaptability. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned existing technologies and to provide a composite organic asphalt and a preparation method for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure. The composite organic asphalt and the preparation method for the clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure can greatly improve the compatibility between the water-stopping asphalt and the concrete interface, thereby greatly improving the anti-seepage performance and greatly improving the ductility under extreme low temperature conditions.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A composite organic asphalt for a clean-drainage wing wall anti-seepage wall tooth groove water-stop structure, comprising the following material components in parts by mass:

[0011] 56-71.4 parts of natural asphalt;

[0012] 22-32 parts of composite modified material;

[0013] 6-8 parts of naphthenic oil;

[0014] 0.4-0.6 parts of trimethyl phosphate crosslinking agent;

[0015] Among them, the raw materials of the composite modified product are proportioned in parts by mass as follows:

[0016] 20-30 parts of thermoplastic polyurethane elastomer;

[0017] 55-65 parts of modified natural rubber powder;

[0018] 2-4 parts of a mixture of a titanate coupling agent and a silane coupling agent;

[0019] 0.3-0.5 parts of organic peroxide cross-linking agent;

[0020] 0.5-1.0 parts of anti-aging agent.

[0021] The invention also comprises 0.5 to 0.7 parts of synthetic phenols and 0.2 to 0.3 parts of benzophenone.

[0022] The synthetic phenol is at least one of alkylated phenol and bisphenol.

[0023] The natural asphalt is at least one of lake asphalt, rock asphalt, ground asphalt and hard asphalt.

[0024] The modified natural rubber powder is surface carboxyl-modified natural rubber powder, and the target particle size is 80 meshes.

[0025] The organic peroxide crosslinking agent is at least one of dicumyl peroxide, benzoyl peroxide and lauroyl peroxide.

[0026] The anti-aging agent is at least one of hindered phenols and natural antioxidants.

[0027] A method for preparing composite organic asphalt for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure comprises the following steps.

[0028] Step 1: preparing modified natural rubber powder: processing the unmodified natural rubber powder to a target particle size of 80 mesh by mechanical or freeze-crushing technology, and sieving; performing surface carboxyl modification treatment on the sieved unmodified natural rubber powder to obtain modified natural rubber powder.

[0029] Step 2: preparing the composite modified product, comprising the following steps.

[0030] Step 2-1: pretreating a mixture of modified natural rubber powder, titanate coupling agent and silane coupling agent to form a rubber powder-coupling agent mixture.

[0031] Step 2-2: drying the thermoplastic polyurethane elastomer.

[0032] Step 2-3: Mix and melt the dried TPU, the rubber powder-coupling agent mixture, the organic peroxide cross-linking agent and the anti-aging agent to form a liquid composite modified product.

[0033] Step 2-4: Cooling, pelletizing and drying the liquid composite modified product to form a granular composite modified product.

[0034] Step 3: The molten natural asphalt, the composite modifier, the synthetic phenols, the benzophenone, the cyclohexane oil and the trimethyl phosphate cross-linking agent are mixed in stages to obtain a composite organic asphalt.

[0035] In step 3, the preparation method of composite organic asphalt includes the following steps.

[0036] The natural asphalt is heated to 140-160°C to form a molten natural asphalt.

[0037] The molten natural asphalt and naphthenic oil are mixed in one stage at 150-160°C to form a homogeneous asphalt matrix.

[0038] The homogeneous asphalt matrix and the composite modifier are mixed in two stages at 170-180°C.

[0039] First, synthetic phenols and benzophenone are added to the second-stage mixture in sequence and mixed evenly; then, trimethyl phosphate crosslinking agent is added and mixed at 170-180°C to form a liquid composite organic asphalt with a TPU-rubber-asphalt interface crosslinking structure.

[0040] The liquid composite organic asphalt is formed, cooled, cut and dried to obtain a solid composite organic asphalt.

[0041] In step 2-2, the moisture content of the thermoplastic polyurethane elastomer after drying must be less than 0.1%; in step 2-4, the moisture content of the granular composite modified product must be ≤0.05%.

[0042] The present invention has the following beneficial effects:

[0043] 1. Effectively solve the problem of insufficient anti-seepage performance of the water-stop asphalt between the wing wall anti-seepage wall and the tooth groove under high water pressure due to the poor compatibility of the traditional asphalt and concrete interface, which leads to a short penetration path.

[0044] The present invention aims to improve the anti-seepage performance of the wing wall anti-seepage wall and the water-stop structure between the tooth grooves under high water pressure environment by chemical bonding and dual mechanisms. The first mechanism relies on the carboxyl modified natural rubber powder (rich in -COOH groups on the surface) and trimethyl phosphate crosslinking agent (C9H 21 The esterification reaction of the rubber powder and the trimethyl phosphate (OP(O)(OCH3)2 groups) is carried out. The activation energy is released during the mixing stage at 170-180℃, which promotes the condensation reaction between the -COOH on the surface of the rubber powder and the -OP(O)(OCH3)2 groups of trimethyl phosphate to form a phosphate bond (-C9H 21O3PO4-R, where R represents the end group of the rubber powder molecular chain. This chemical bond acts as a molecular "rivet," directly anchoring the rubber powder's rigid skeleton (80-mesh particle size forms the initial physical screening barrier) to the asphalt matrix through covalent bonds, forming a continuous phase network dominated by chemical crosslinking—a process known as "chemical anchoring." This anchoring effect not only eliminates the compatibility defects of the rubber powder and asphalt interface found in traditional materials, but also, through the rigid connection of phosphate bonds, enables the rubber powder to form a stable supporting skeleton within the asphalt matrix, forming a "first-level crosslinking network" that prevents linear water penetration and directly cuts off the shortcut permeation channel under high water pressure.

[0045] On this basis, the second mechanism is through the thermal decomposition of the organic peroxide crosslinker (such as di-tert-butyl peroxide) premixed in the composite modifier to produce free radicals (such as ·Ot-C4H9), which triggers the free radical polymerization reaction of the carbamate hard segment (-NH-COO-) in the TPU molecular chain. Adjacent TPU molecular chains form covalent crosslinking nodes through methylene bridges (-CH2-), and then interpenetrate with the chemically anchored rubber powder-asphalt network to form a "rubber powder-TPU-asphalt" interpenetrating network structure. This interpenetrating structure is similar to two interwoven three-dimensional mesh fabrics. The elastic network formed by the crosslinking of TPU wraps around the rigid skeleton of the rubber powder, and at the same time entangles with the asphalt molecular chains through van der Waals forces and local hydrogen bonds, so that the solid phase particles (rubber powder, mineral powder) and the polymer matrix in the entire system form a spatial network. When water tries to penetrate, it must constantly detour around the surface of rubber powder particles, pass through the gaps between TPU cross-linked nodes, and cross the entanglement area of ​​asphalt molecular chains in this complex network, resulting in a significant increase in the "permeation path tortuosity" (i.e., the ratio of the actual permeation path length to the straight-line distance) to more than three times the original value. The mathematical expression of tortuosity can be approximated as τ = √(1 + α 2 )(α is the path deflection coefficient), when the tortuosity increases by more than 3 times, the viscous resistance that water penetration needs to overcome is calculated as τ 2 The proportion of growth, combined with the dense network filling effect on the pores, ultimately makes the material permeability coefficient increase from 10 of the traditional modified asphalt. -7 cm / s level down to 10 -9 cm / s, its water resistance rating has been raised from P8 of traditional materials to P16, effectively resisting seepage damage in high water pressure environments of 80m-160m. This dual mechanism works synergistically, strengthening interfacial bonding through chemical cross-linking and extending the permeation path through the steric hindrance effect of the interpenetrating network. This effectively blocks high-pressure water penetration at both the molecular bonding and macrostructural scales, providing dual protection of chemical stability and spatial density for the water-stopping structure between the wing wall anti-seepage wall tooth groove and the anti-seepage wall.

[0046] 2. Effectively solve the problem that the asphalt traditionally used in the tooth groove water-stop structure of the wing wall anti-seepage wall is difficult to withstand extreme temperature conditions, resulting in water-stop failure.

[0047] During the preparation process, the composite organic asphalt constructs a permanent temperature-resistant structure through three key chemical reactions: first, in the melting stage (170-180°C), the phosphoryl group (P=O) of trimethyl phosphate ((CH3O)3P=O) attacks the carboxyl group (-COOH) on the surface of the carboxylated rubber powder, and an esterification reaction occurs to form a rigid phosphate bridge bond (chemical formula: R-COOH+(CH3O)3P=O→RC(O)-OP(O)(OCH3)-O-asphalt), which permanently anchors the 80-mesh rubber particles (physical barrier) to the asphalt matrix; at the same time, organic peroxides (such as diisopropylbenzene peroxide, structural formula (CH3)2C-OO-C(CH3)2) decompose upon heating to produce alkoxy free radicals (·OR), which trigger the covalent crosslinking of the TPU hard segment urethane groups (-NH-COO-) (reaction formula:

[0048] 2TPU-NH-COO+·OR→TPU-N(COO)-N(COO)-TPU+ROH), then in the coupling agent premixing stage, titanate monoalkoxy (such as isopropyl trioleoyl titanate, (CH3)2CH-O-Ti-(OCOR)3) is hydrolyzed and condensed with the mineral powder hydroxyl to form a hydrophobic layer (-Ti-O-filler), and silane (such as KH-550, H2N(CH2)3Si(OCH3)3) is passed through silicon Oxyalkyl groups (-Si-O-Si-) bond the filler, while amino groups (-NH2) form hydrogen bonds (-C=O···HN-) with the carboxyl groups of the asphalt. This triple chemical bond (phosphate, covalent, and hydrogen) is permanently locked in after cooling and solidification (step four, rapid cooling at 10-15°C). The phosphate bonds (bond energy 380kJ / mol) and covalent bonds (bond energy 347kJ / mol) ensure that the prepared asphalt maintains structural stability even at temperatures of 75°C. Hydrogen bonds (-O···HC-, bond energy 17kJ / mol) within the flexible network of the TPU soft segment (long-chain polyol) and naphthenic oil ensure the stability of the asphalt structure even at -40°C, preventing freeze cracking. The three chemical bonds formed ultimately enable the material to form a permanent structure that is resistant to softening at 75°C and freezing cracking at -40°C before it is put into service, breaking through the 45°C temperature range limit of traditional asphalt (-5 to 40°C) and meeting the overall structure of the anti-seepage wall and the anti-seepage needs in extreme environments.

[0049] 3. Solve the problem of high carbon emissions from the traditional asphalt used in the wing wall anti-seepage wall tooth groove water-stop structure and difficulty in achieving permanent solid waste.

[0050] The present invention aims to solve the problem that heavy metal catalysts (lead, cadmium compounds) and high aromatic components (aromatics>30%) in asphalt materials used in traditional anti-seepage wall grooves and anti-seepage wall water-stop structures cause excessive VOCs emissions (>200mg / m 3), recycled rubber powder carries PAHs pollutants (benzo[a]pyrene ≥ 1.2 mg / kg), the high-temperature mixing process of >180℃ leads to a carbon emission intensity of 120 kg / t, and the landfill rate of difficult-to-degrade components exceeds 70%, forming permanent solid waste and other systemic environmental bottlenecks. Breakthroughs are achieved through the following material innovations and process collaboration: natural asphalt (56 to 71.4 parts) is used as the matrix, and composite modifiers (22 to 32 parts) are used as the core functional components - the soft segment of thermoplastic polyurethane elastomer (TPU, 20 to 30 parts) contains a hydrolyzable ester structure, and the hard segment (urethane) The chain segments) and carboxyl modified natural rubber powder (80 mesh, 55-65 parts) lock the aromatic molecules through hydrogen bonding (NH…O=C), and are combined with synthetic phenols (0.5-0.7 parts) and benzophenone (0.2-0.3 parts) to completely replace heavy metal catalysts, eliminating the pollution source from the source; at the same time, based on the synergistic treatment of titanate and silane coupling agent (2-4 parts) (titanium ester coated filler reduces polarity, silane bridges chemical bonds) to block the PAHs (benzo[a]pyrene <0.01mg / kg) introduced by the recycled rubber powder, and suppress VOCs emissions to ≤40mg / m 3 At the process level, an innovative design uses low-temperature melt mixing at 140-160°C and terminal cross-linking at 170-180°C. Trimethyl phosphate cross-linking agent (0.4-0.6 parts) is used to activate the residual organic peroxide (0.3-0.5 parts) in the composite modifier to form a double cross-linked network (TPU-rubber-asphalt), which reduces energy consumption by 40% (carbon emissions ≤55kg / t) compared to the traditional process at >190°C. Combined with rapid cooling and curing in a 10-15°C water bath, high-temperature volatilization is suppressed. After failure, the material promotes microbial metabolism due to the hydrolyzable characteristics of the TPU ester bond (biodegradation rate >50%) and cyclohexane oil (6-8 parts), combined with physical crushing (80 mesh rubber powder increases the specific surface area), and the final landfill rate is reduced from >70% to ≤30%, effectively solving the problem of difficult-to-degrade solid waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A structural schematic diagram of the existing net-drainage wing wall anti-seepage wall groove water-stop structure is shown.

[0052] Among them are:

[0053] 1. Anti-seepage wall; 2. Anti-seepage wall groove; 3. Wing wall base plate; 4. Water-stop asphalt. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below with reference to the accompanying drawings and specific preferred embodiments.

[0055] In the description of the present invention, it should be understood that the terms "left side," "right side," "upper," "lower," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Terms such as "first" and "second" do not indicate the importance of components and therefore should not be construed as limitations on the present invention. The specific dimensions used in this embodiment are intended only to illustrate the technical solution and do not limit the scope of protection of the present invention.

[0056] A composite organic asphalt for a net-drainage wing wall anti-seepage wall tooth groove water-stopping structure comprises the following material components in parts by mass: 56 to 71.4 parts of natural asphalt, 22 to 32 parts of a composite modifier, 0.5 to 0.7 parts of a synthetic phenol, 0.2 to 0.3 parts of benzophenone, 6 to 8 parts of cyclohexane oil, and 0.4 to 0.6 parts of a trimethyl phosphate cross-linking agent.

[0057] The above-mentioned natural asphalt is preferably at least one of lake asphalt, rock asphalt, ground asphalt and hard asphalt. Considering the high durability requirements of large buildings such as anti-seepage walls, lake asphalt or hard asphalt is preferably recommended.

[0058] The above-mentioned synthetic phenols are preferably at least one of alkylated phenol and bisphenol, and alkylated phenol and bisphenol are based on the chemical activity of their phenolic hydroxyl groups, the steric effect of alkylation or substituents, and unique molecular structure, which can efficiently capture free radicals and effectively terminate chain reactions. In addition, by introducing benzophenone materials, the stability of free radical traps can be significantly enhanced, particularly under high temperature or illumination environments, benzophenone can suppress the generation and propagation of free radicals by an energy transfer mechanism, thereby significantly improving the performance of free radical traps. Based on the above-mentioned synergistic effect, the combination of the alkylated phenol, bisphenol and benzophenone can prepare a free radical trap with excellent performance, which is applicable to a variety of complex application scenarios. The free radical trap prepared using this method can effectively promote the free radical aggregation produced by asphalt during aging, and by suppressing the progress of free radical oxidation reaction, significantly improve the anti-aging properties of asphalt, further improve its high temperature resistance, fatigue resistance and long-term durability, to achieve the comprehensive improvement of asphalt material service life and comprehensive performance.

[0059] The raw materials of the above-mentioned composite modified product are proportioned as follows by mass: 20-30 parts of thermoplastic polyurethane elastomer, 55-65 parts of modified natural rubber powder, 2-4 parts of a mixture of titanate coupling agent and silane coupling agent, 0.3-0.5 parts of an organic peroxide crosslinking agent and 0.5-1.0 parts of an anti-aging agent.

[0060] The thermoplastic polyurethane elastomer (TPU) comprises a hard segment and a soft segment; wherein the hard segment is a urethane segment generated by the reaction of isocyanate and a chain extender (such as butanediol); and the soft segment is a long-chain polyol.

[0061] The modified natural rubber powder is a natural rubber powder whose surface is carboxyl-modified by using an oxidant such as potassium permanganate or hydrogen peroxide, and the target particle size is 80 mesh, that is, the particle size is about 80 mesh.

[0062] This modification of the natural rubber powder not only increases its surface activity, making it easier to bond with the asphalt matrix, but also strengthens the chemical bond between the rubber powder and the asphalt by introducing carboxyl groups, significantly enhancing the mechanical properties and durability of the composite organic asphalt. Furthermore, the 80-mesh particle size ensures uniform dispersion of the rubber powder in the asphalt, avoiding uneven performance issues caused by overly large or undersized particles.

[0063] The above-mentioned organic peroxide crosslinking agent is preferably at least one of dicumyl peroxide, benzoyl peroxide, and lauroyl peroxide. These crosslinking agents decompose at high temperatures to produce free radicals (such as ·Ot-C4H9), which trigger the free radical polymerization of the carbamate groups in the TPU hard segment, forming covalent crosslinking nodes. These nodes interpenetrate with the rubber powder-asphalt network to form a "rigid and flexible" spatial network, increasing the tortuosity of the permeation path by more than 3 times and enhancing anti-permeation. The covalent crosslinking (bond energy 347kJ / mol) initiated by them synergistically locks the high-temperature stable structure with the phosphate bonds, while helping the hydrogen bonds of the TPU soft segment maintain low-temperature flexibility. In the process, the residual crosslinking agent is activated by trimethyl phosphate to form a double network, reducing the terminal crosslinking temperature to 170-180°C, reducing energy consumption by 40% and improving the material's degradability.

[0064] The aforementioned antioxidant is preferably at least one of a hindered phenolic group and a natural antioxidant. These antioxidants can effectively capture free radicals, preventing or delaying the aging process of the composite organic asphalt under environmental factors such as heat, oxygen, and light. Hindered phenolic antioxidants react with free radicals through their phenolic hydroxyl groups to form stable phenoloxyl radicals, thereby terminating the chain reaction and protecting the asphalt molecules from damage. Natural antioxidants, through the antioxidant active substances in their natural components, provide an additional layer of protection, further enhancing the durability and service life of the composite organic asphalt.

[0065] The preparation method of the above titanate coupling agent and silane coupling agent mixture is preferably:

[0066] A. Premix 1-3% titanate coupling agent with inorganic fillers, such as mineral powder, under high-speed stirring at 80-120°C, so that the surface of the inorganic filler is coated with the monoalkoxy structure.

[0067] B. Add 0.5-2% of silane coupling agent to use its siloxane group to react with the hydroxyl group of the inorganic filler, and at the same time, the organic end forms a chemical bond with the asphalt.

[0068] When titanate coupling agents are combined with silane coupling agents, the titanate preferentially adsorbs on the filler surface, reducing its polarity and improving dispersibility, while the silane further bridges the filler and asphalt. This synergistic effect strengthens interfacial bonding, reduces filler agglomeration, and significantly improves the asphalt's high-temperature stability, low-temperature crack resistance, and aging resistance. The hydrophobicity of the titanate complements the chemical bonding of the silane, jointly optimizing the asphalt's rheological properties and durability.

[0069] Titanate coupling agent and silane coupling agent play a key role in three aspects: in improving the anti-permeability performance, titanate condenses with the hydroxyl group of mineral powder after hydrolysis to form a hydrophobic layer (-Ti-O-filler), silane bonds the filler through the siloxane group (-Si-O-Si-), and the amino group (-NH2) forms a hydrogen bond bridge with the asphalt carboxyl group (-C=O···HN-), strengthening the interface bonding force of the "rubber powder-TPU-asphalt" interpenetrating network, and coordinating chemical cross-linking and physical entanglement to construct a multi-dimensional permeation barrier and extend the permeation path; in extreme temperature adaptation, its The triple chemical bonds (phosphate bond, covalent bond, hydrogen bond) involved in the formation are permanently locked after cooling and solidification. The interface connection enhanced by titanate and silane helps the rigid phosphate bond (380kJ / mol) and covalent bond (347kJ / mol) to withstand high temperatures, and the hydrogen bond (17kJ / mol) maintains low-temperature flexibility. At the environmental protection level, titanate-coated fillers reduce polarity and silane bridges chemical bonds, blocking PAHs pollution in recycled rubber powder and reducing VOCs emissions through hydrogen bond networks. The low-temperature process and material degradability synergistically reduce carbon emissions and landfill rates.

[0070] A method for preparing composite organic asphalt for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure comprises the following steps.

[0071] Step 1: Prepare modified natural rubber powder: The pre-modified natural rubber powder is mechanically or freeze-milled to a target particle size of 80 mesh and sieved to achieve uniform particle size. The sieved pre-modified natural rubber powder is surface carboxylated using an oxidizing agent such as potassium permanganate or hydrogen peroxide, maintaining a temperature between 30 and 60°C to ensure effective modification. After completion, the modified natural rubber powder is washed with deionized water to thoroughly remove any unreacted oxidizing agent and byproducts of the modification. Finally, the washed modified natural rubber powder is dried in a vacuum drying oven at 50 to 60°C to a constant weight, yielding surface carboxylated modified natural rubber powder.

[0072] Step 2: preparing the composite modified product, comprising the following steps.

[0073] Step 2-1: Pre-treat the modified natural rubber powder, titanate coupling agent, and silane coupling agent mixture, mix them evenly, and then let them stand for 30 minutes to allow the coupling agent to fully infiltrate the surface of the modified natural rubber powder, forming a rubber powder-coupling agent mixture. The pre-treatment method is preferably: pre-mix the carboxylated modified natural rubber powder (80 mesh), titanate coupling agent, and silane coupling agent mixture in proportion; then, stir in a high-speed stirrer (e.g., at a speed of 500-800 rpm) for 5-10 minutes to allow the coupling agent to evenly coat the surface of the rubber powder and enhance interfacial bonding.

[0074] Step 2-2: Dry the thermoplastic polyurethane elastomer. The preferred drying method is to dry the thermoplastic polyurethane elastomer (TPU) in an oven at 60-100°C for 4-6 hours, ensuring a moisture content below 0.1%. This prevents bubbles and degradation during processing, thereby ensuring processing stability of the TPU and consistent performance of the final product. Moisture content should be regularly monitored during the drying process to ensure it meets target requirements.

[0075] Step 2-3: First, the dried TPU, the rubber powder-coupling agent mixture, the organic peroxide crosslinking agent, and the anti-aging agent are preferably added to a high-speed mixer for mixing. The mixing method in the high-speed mixer is preferably as follows: the dried TPU and the rubber powder-coupling agent mixture are added to the high-speed mixer and initially mixed at 50-70°C for 5 minutes; then, the organic peroxide crosslinking agent and the anti-aging agent are added and mixed for 10-15 minutes until uniformly dispersed. This ensures that all components are thoroughly mixed and evenly dispersed, providing a homogeneous raw material for subsequent melt blending. The temperature and speed must be controlled during the mixing process to avoid degradation of material properties due to excessive temperature or excessive shear forces.

[0076] Next, the above-mentioned mixed material is preferably fed into a twin-screw extruder to promote melt blending using shear force to form a liquid composite modified product. The melt blending method is preferably as follows: the mixed material is fed into a twin-screw extruder, and the temperature gradient is set to: 160-170°C in zone 1, 170-180°C in zone 2, 175-185°C in zone 3, and 180-190°C in the die head. The screw speed is controlled at 200-300 r / min, and shear force is used to promote melt blending. At the same time, the organic peroxide decomposes at high temperature to induce mild crosslinking of the TPU and rubber powder, thereby optimizing the mechanical properties and thermal stability of the composite modified product. During the extrusion process, the temperature and screw speed of each zone must be strictly controlled to ensure uniform melting of the material and sufficient crosslinking reaction.

[0077] Step 2-4: Cool, pelletize, and dry the liquid composite modified product. In this embodiment, the extruded material is preferably immersed in a 10-15°C water bath for rapid cooling and solidification to prevent phase separation of the components; then, after cooling, pelletize (e.g., sheets or granules) to obtain composite particles with a diameter of approximately 3 mm; then, the composite particles are placed in a 60°C oven and dried for 2-4 hours to ensure a moisture content of ≤0.05%, and then sealed and stored in a dark place until ready for use. This yields the composite modified product.

[0078] Step 3: The molten natural asphalt, the composite modifier, the synthetic phenols, the benzophenone, the cyclohexane oil and the trimethyl phosphate cross-linking agent are mixed in stages to obtain a composite organic asphalt.

[0079] The preparation method of the composite organic asphalt includes the following steps.

[0080] A. Melting stage: Heat the natural asphalt to 140-160°C to avoid oxidation of the natural asphalt and form a molten state of natural asphalt.

[0081] B. Mixing stage, preferably in three stages

[0082] In the first stage, molten natural asphalt and naphthenic oil are added to a high-speed shear reactor and mixed for 10 minutes at 150-160°C and a rotational speed of 300-400 rpm to form a homogeneous asphalt matrix, providing a stable foundation for subsequent modification. Temperature and rotational speed must be controlled during the mixing process to ensure the uniformity and stability of the asphalt matrix.

[0083] In the second stage, the composite modifier is added, the temperature is raised to 170-180°C, the rotation speed is increased to 500-600 rpm, and shearing is continued for 20-30 minutes to ensure that the composite modifier is evenly dispersed in the asphalt matrix, thereby improving the interfacial compatibility and mechanical properties of the composite organic asphalt. The temperature and rotation speed must be strictly controlled during the mixing process to prevent thermal degradation of the TPU and ensure that the modifier is fully integrated into the asphalt matrix.

[0084] In the third stage, synthetic phenols and benzophenone are added sequentially. After mixing for 5 minutes, trimethyl phosphate crosslinker is slowly added. The temperature is maintained at 170-180°C, and the reaction continues for 15-20 minutes to form a liquid composite organic asphalt with a crosslinked TPU-rubber-asphalt interface. Adding the trimethyl phosphate crosslinker late at high temperatures ensures that the active ingredients effectively trigger crosslinking. This crosslinked TPU-rubber-asphalt interface enhances the material's thermal stability and mechanical strength.

[0085] Finally, the liquid composite organic asphalt is extruded or injection molded through a mold and then immersed in a 10-15°C water bath for rapid cooling and solidification to prevent phase separation. It is then cut into the desired specifications (e.g., sheets or pellets) and dried in a 40-50°C oven for two hours to remove surface moisture. This results in a solid, clean-drainage composite organic asphalt for anti-seepage wall groves.

[0086] The present invention is preferably described in detail using the following five embodiments.

[0087] Example 1

[0088] A composite organic asphalt (1#) for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure, wherein the composite modified asphalt is used for the wing wall anti-seepage wall tooth groove water-stopping structure and comprises the following components in parts by weight:

[0089]

[0090] The preparation method of the composite modified product comprises the following steps: drying a thermoplastic polyurethane elastomer (TPU) to a moisture content of ≤0.05%; premixing carboxyl-modified natural rubber powder with a titanate coupling agent and a silane coupling agent so that the coupling agent uniformly covers the surface of the rubber powder; adding the dried TPU, premixed rubber powder, an organic peroxide crosslinking agent, and an anti-aging agent into a high-speed mixer and mixing them uniformly; feeding the mixture into a twin-screw extruder, utilizing shear force to promote melt blending, while the organic peroxide decomposes to induce mild crosslinking between the TPU and the rubber powder; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of approximately 3 mm; drying the particles in an oven at 60°C for 2 to 4 hours to ensure that the moisture content is ≤0.05%, and storing them in a sealed container away from light to obtain the composite modified product.

[0091] Among them, natural asphalt is lake asphalt.

[0092] The composite modified material includes the following components in parts by mass:

[0093] 20 parts thermoplastic polyurethane elastomer

[0094] 65 parts of modified natural rubber powder

[0095] 4 parts of titanate coupling agent and silane coupling agent

[0096] 0.3 parts of organic peroxide crosslinking agent

[0097] 0.5 parts of anti-aging agent.

[0098] The modified natural rubber powder is processed mechanically or freeze-milled to a target particle size of 80 mesh and then screened to ensure uniform particle size. The rubber powder is surface-carboxylated using an oxidizing agent such as potassium permanganate or hydrogen peroxide while controlling the temperature. Unreacted reagents are removed by washing, and the modified natural rubber powder is then vacuum-dried to obtain the modified natural rubber powder.

[0099] The organic peroxide cross-linking agent is dicumyl peroxide.

[0100] The above-mentioned antioxidant is hindered phenol.

[0101] A method for preparing a composite organic asphalt for a clean-drainage wing wall anti-seepage wall tooth groove water-stop structure comprises the following steps:

[0102] (1) processing natural rubber powder by mechanical pulverization or freeze pulverization technology to a target particle size of 80 mesh, and sieving to ensure particle size uniformity; using an oxidant to perform surface carboxylation treatment on the rubber powder, wherein the oxidant is selected from potassium permanganate or hydrogen peroxide, and the temperature is controlled in the range of 30° C. to 60° C. during the reaction; washing the rubber powder after the reaction to remove unreacted oxidant, and then drying under vacuum conditions to a moisture content of ≤0.5%, to obtain 65 parts by mass of modified natural rubber powder;

[0103] (2) drying the thermoplastic polyurethane elastomer (TPU) to a water content of ≤0.1%; premixing the modified natural rubber powder prepared in step 1 with a coupling agent to form a rubber powder-coupling agent mixture; adding 20 parts by mass of the dried TPU, 22 parts by mass of the pretreated rubber powder-coupling agent mixture, 0.4 parts by mass of an organic peroxide crosslinking agent, and 0.5 parts by mass of an anti-aging agent to a high-speed mixer, and mixing at 3000 r / min for 10 minutes until uniform; feeding the mixture into a twin-screw extruder, and melt-blending at a temperature of 160-180°C and a speed of 200 r / min, using shear force to promote interfacial bonding; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of about 3 mm; drying the particles in a 60°C oven for 2-4 hours to ensure that the water content is ≤0.05%, and storing them in a sealed, dark-proof manner for later use, thereby obtaining a composite modified product;

[0104] (3) 71.4 parts by mass of natural asphalt was heated to a molten state, and 22 parts by mass of the composite modifier prepared in step 2, 0.5 parts by mass of synthetic phenols, 0.2 parts by mass of benzophenone, 6 parts by mass of cyclohexane oil and 0.4 parts by mass of trimethyl phosphate crosslinking agent were added in sequence, and mixed in stages: in the first stage, stirring at 140°C and 500 r / min for 20 minutes was performed to achieve preliminary dispersion; in the second stage, the temperature was raised to 160°C and high-speed shearing was performed at 1000 r / min for 40 minutes to promote component homogenization;

[0105] (4) Maintaining the temperature at 170-180°C at the end of the mixing process, a synergistic cross-linking reaction occurs between trimethyl phosphate and the residual organic peroxide in the composite modifier to form a TPU-rubber-asphalt interface double cross-linking structure; extruding the mixture through a mold or injection molding, and then immersing it in a 10-15°C water bath for rapid cooling and solidification, with a cooling rate of ≥20°C / min, to prevent phase separation of the components; cutting the molded material into sheets or granules, placing it in an oven at 40-50°C for 2 hours, and removing surface moisture to a moisture content of ≤0.1%, thereby obtaining a composite organic asphalt for a net-drainage type wing wall anti-seepage wall tooth groove water-stopping structure.

[0106] Example 2

[0107] A composite organic asphalt (2#) for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure. The composite modified asphalt is used for the wing wall anti-seepage wall tooth groove water-stopping structure and comprises the following components in parts by weight:

[0108]

[0109] The preparation method of the composite modified product comprises the following steps: drying a thermoplastic polyurethane elastomer (TPU) to a moisture content of ≤0.05%; premixing carboxyl-modified natural rubber powder with a titanate coupling agent and a silane coupling agent so that the coupling agent uniformly covers the surface of the rubber powder; adding the dried TPU, premixed rubber powder, an organic peroxide crosslinking agent, and an anti-aging agent into a high-speed mixer and mixing them uniformly; feeding the mixture into a twin-screw extruder, utilizing shear force to promote melt blending, while the organic peroxide decomposes to induce mild crosslinking between the TPU and the rubber powder; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of approximately 3 mm; drying the particles in an oven at 60°C for 2 to 4 hours to ensure that the moisture content is ≤0.05%, and storing them in a sealed container away from light to obtain the composite modified product.

[0110] Among them: natural asphalt is lake asphalt.

[0111] The composite modified material includes the following components in parts by mass:

[0112]

[0113] The organic peroxide cross-linking agent is benzoyl peroxide.

[0114] The above-mentioned antioxidant is hindered phenol.

[0115] The preparation method of the composite modified asphalt includes the following steps.

[0116] (1) processing natural rubber powder by mechanical pulverization or freeze pulverization technology to a target particle size of 80 mesh, and sieving to ensure particle size uniformity; using an oxidant to perform surface carboxylation treatment on the rubber powder, wherein the oxidant is selected from potassium permanganate or hydrogen peroxide, and the temperature is controlled in the range of 30° C. to 60° C. during the reaction; washing the rubber powder after the reaction to remove unreacted oxidant, and then drying under vacuum conditions to a moisture content of ≤0.5%, to obtain 60 parts by mass of modified natural rubber powder;

[0117] (2) drying the thermoplastic polyurethane elastomer (TPU) to a water content of ≤0.1%; premixing the modified natural rubber powder prepared in step 1 with a coupling agent to form a rubber powder-coupling agent mixture; adding 30 parts by mass of the dried TPU, 26 parts by mass of the pretreated rubber powder-coupling agent mixture, 0.5 parts by mass of an organic peroxide crosslinking agent, and 0.5 parts by mass of an anti-aging agent to a high-speed mixer, and mixing at 3000 r / min for 10 minutes until uniform; feeding the mixture into a twin-screw extruder, and melt-blending at a temperature of 160-180°C and a speed of 200 r / min, using shear force to promote interfacial bonding; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of about 3 mm; drying the particles in a 60°C oven for 2-4 hours to ensure that the water content is ≤0.05%, and storing them in a sealed, dark-proof manner for later use, thereby obtaining a composite modified product;

[0118] (3) 70.4 parts by mass of natural asphalt was heated to a molten state, and 26 parts by mass of the composite modifier prepared in step 2, 0.6 parts by mass of synthetic phenols, 0.3 parts by mass of benzophenone, 5 parts by mass of cyclohexane oil and 0.2 parts by mass of trimethyl phosphate crosslinking agent were added in sequence, and mixed in stages: in the first stage, stirring at 140°C and 500 r / min for 20 minutes was performed to achieve preliminary dispersion; in the second stage, the temperature was raised to 160°C and high-speed shearing was performed at 1000 r / min for 40 minutes to promote homogenization of the components;

[0119] (4) Maintaining the temperature at 170-180°C at the end of the mixing process, a synergistic cross-linking reaction occurs between trimethyl phosphate and the residual organic peroxide in the composite modifier to form a TPU-rubber-asphalt interface double cross-linking structure; extruding the mixture through a mold or injection molding, and then immersing it in a 10-15°C water bath for rapid cooling and solidification, with a cooling rate of ≥20°C / min, to prevent phase separation of the components; cutting the molded material into sheets or granules, placing it in an oven at 40-50°C for 2 hours, and removing surface moisture to a moisture content of ≤0.1%, thereby obtaining a composite organic asphalt for a net-drainage type wing wall anti-seepage wall tooth groove water-stopping structure.

[0120] Example 3

[0121] A composite organic asphalt (3#) for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure. The composite modified asphalt is used for the wing wall anti-seepage wall tooth groove water-stopping structure and comprises the following components in parts by weight:

[0122]

[0123] The preparation method of the composite modified product comprises the following steps: drying a thermoplastic polyurethane elastomer (TPU) to a moisture content of ≤0.05%; premixing carboxyl-modified natural rubber powder with a titanate coupling agent and a silane coupling agent so that the coupling agent uniformly covers the surface of the rubber powder; adding the dried TPU, premixed rubber powder, an organic peroxide crosslinking agent, and an anti-aging agent into a high-speed mixer and mixing them uniformly; feeding the mixture into a twin-screw extruder, utilizing shear force to promote melt blending, while the organic peroxide decomposes to induce mild crosslinking between the TPU and the rubber powder; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of approximately 3 mm; drying the particles in an oven at 60°C for 2 to 4 hours to ensure that the moisture content is ≤0.05%, and storing them in a sealed container away from light to obtain the composite modified product.

[0124] Among them, natural asphalt is lake asphalt.

[0125] The composite modified material includes the following components in parts by mass:

[0126] 25 parts thermoplastic polyurethane elastomer

[0127] 64 parts of modified natural rubber powder

[0128] 3 parts of titanate coupling agent and silane coupling agent

[0129] 0.4 parts of organic peroxide crosslinking agent

[0130] 0.8 parts of anti-aging agent.

[0131] The organic peroxide cross-linking agent is lauroyl peroxide.

[0132] The above-mentioned antioxidant is hindered phenol.

[0133] Modified natural rubber powder is processed mechanically or freeze-milled to a target particle size of 80 mesh and then screened to ensure uniform particle size. The surface of the rubber powder is carboxylated using an oxidizing agent such as potassium permanganate or hydrogen peroxide while controlling the temperature. Unreacted reagents are removed by washing, and the modified natural rubber powder is then vacuum-dried.

[0134] A method for preparing composite modified asphalt includes the following steps.

[0135] (1) processing natural rubber powder by mechanical pulverization or freeze pulverization technology to a target particle size of 80 mesh, and sieving to ensure particle size uniformity; using an oxidant to perform surface carboxylation treatment on the rubber powder, wherein the oxidant is selected from potassium permanganate or hydrogen peroxide, and the temperature is controlled in the range of 30° C. to 60° C. during the reaction; washing the rubber powder after the reaction to remove unreacted oxidant, and then drying under vacuum conditions to a moisture content of ≤0.5%, thereby obtaining 68.4 parts by mass of modified natural rubber powder;

[0136] (2) drying the thermoplastic polyurethane elastomer (TPU) to a water content of ≤0.1%; premixing the modified natural rubber powder prepared in step 1 with a coupling agent to form a rubber powder-coupling agent mixture; adding 25 parts by mass of the dried TPU, 28 parts by mass of the pretreated rubber powder-coupling agent mixture, 0.4 parts by mass of an organic peroxide crosslinking agent, and 0.8 parts by mass of an anti-aging agent to a high-speed mixer, and mixing at 3000 r / min for 10 minutes until uniform; feeding the mixture into a twin-screw extruder, and melt-blending at a temperature of 160-180°C and a speed of 200 r / min, using shear force to promote interfacial bonding; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of about 3 mm; drying the particles in a 60°C oven for 2-4 hours to ensure that the water content is ≤0.05%, and storing them in a sealed, dark-proof manner for later use, thereby obtaining a composite modified product;

[0137] (3) 68.4 parts by mass of natural asphalt were heated to a molten state, and 28 parts by mass of the composite modifier prepared in step 2, 0.7 parts by mass of synthetic phenols, 0.3 parts by mass of benzophenone, 8 parts by mass of cyclohexane oil, and 0.6 parts by mass of trimethyl phosphate crosslinking agent were added in sequence, and mixed in stages: in the first stage, stirring at 140°C and 500 r / min for 20 minutes was performed to achieve preliminary dispersion; in the second stage, the temperature was raised to 160°C and high-speed shearing was performed at 1000 r / min for 40 minutes to promote component homogenization;

[0138] (4) Maintaining the temperature at 170-180°C at the end of the mixing process, a synergistic cross-linking reaction occurs between trimethyl phosphate and the residual organic peroxide in the composite modifier to form a TPU-rubber-asphalt interface double cross-linking structure; extruding the mixture through a mold or injection molding, and then immersing it in a 10-15°C water bath for rapid cooling and solidification, with a cooling rate of ≥20°C / min, to prevent phase separation of the components; cutting the molded material into sheets or granules, placing it in an oven at 40-50°C for 2 hours, and removing surface moisture to a moisture content of ≤0.1%, thereby obtaining a composite organic asphalt for a net-drainage type wing wall anti-seepage wall tooth groove water-stopping structure.

[0139] Example 4

[0140] A composite organic asphalt (4#) for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure. The composite modified asphalt is used for the wing wall anti-seepage wall tooth groove water-stopping structure and comprises the following components in parts by weight:

[0141]

[0142] The preparation method of the composite modified product comprises the following steps: drying a thermoplastic polyurethane elastomer (TPU) to a moisture content of ≤0.05%; premixing carboxyl-modified natural rubber powder with a titanate coupling agent and a silane coupling agent so that the coupling agent uniformly covers the surface of the rubber powder; adding the dried TPU, premixed rubber powder, an organic peroxide crosslinking agent, and an anti-aging agent into a high-speed mixer and mixing them uniformly; feeding the mixture into a twin-screw extruder, utilizing shear force to promote melt blending, while the organic peroxide decomposes to induce mild crosslinking between the TPU and the rubber powder; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of approximately 3 mm; drying the particles in an oven at 60°C for 2 to 4 hours to ensure that the moisture content is ≤0.05%, and storing them in a sealed container away from light to obtain the composite modified product.

[0143] Among them, natural asphalt is lake asphalt.

[0144] The composite modified material includes the following components in parts by mass:

[0145]

[0146] The organic peroxide cross-linking agent is benzoyl peroxide.

[0147] The above-mentioned antioxidant is hindered phenol.

[0148] Modified natural rubber powder is processed mechanically or freeze-milled to a target particle size of 80 mesh and then screened to ensure uniform particle size. The surface of the rubber powder is carboxylated using an oxidizing agent such as potassium permanganate or hydrogen peroxide while controlling the temperature. Unreacted reagents are removed by washing, and the modified natural rubber powder is then vacuum-dried.

[0149] A method for preparing composite modified asphalt includes the following steps.

[0150] (1) processing natural rubber powder by mechanical pulverization or freeze pulverization technology to a target particle size of 80 mesh, and sieving to ensure particle size uniformity; using an oxidant to perform surface carboxylation treatment on the rubber powder, wherein the oxidant is selected from potassium permanganate or hydrogen peroxide, and the temperature is controlled in the range of 30° C. to 60° C. during the reaction; washing the reacted rubber powder to remove unreacted oxidant, and then drying under vacuum conditions to a moisture content of ≤0.5%, thereby obtaining 66.4 parts by mass of modified natural rubber powder;

[0151] (2) drying the thermoplastic polyurethane elastomer (TPU) to a water content of ≤0.1%; premixing the modified natural rubber powder prepared in step 1 with a coupling agent to form a rubber powder-coupling agent mixture; adding 28 parts by mass of the dried TPU, 30 parts by mass of the pretreated rubber powder-coupling agent mixture, 0.5 parts by mass of an organic peroxide crosslinking agent, and 0.7 parts by mass of an anti-aging agent to a high-speed mixer, and mixing at 3000 r / min for 10 minutes until uniform; feeding the mixture into a twin-screw extruder, and melt-blending at a temperature of 160-180°C and a speed of 200 r / min, using shear force to promote interfacial bonding; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of about 3 mm; drying the particles in a 60°C oven for 2-4 hours to ensure that the water content is ≤0.05%, and storing them in a sealed, dark-proof manner for later use, thereby obtaining a composite modified product;

[0152] (3) 66.4 parts by mass of natural asphalt were heated to a molten state, and 30 parts by mass of the composite modifier prepared in step 2, 0.6 parts by mass of synthetic phenols, 0.3 parts by mass of benzophenone, 7 parts by mass of cyclohexane oil, and 0.4 parts by mass of trimethyl phosphate crosslinking agent were added in sequence, and mixed in stages: in the first stage, stirring at 140°C and 500 r / min for 20 minutes was performed to achieve preliminary dispersion; in the second stage, the temperature was raised to 160°C and high-speed shearing was performed at 1000 r / min for 40 minutes to promote component homogenization;

[0153] (4) Maintaining the temperature at 170-180°C at the end of the mixing process, a synergistic cross-linking reaction occurs between trimethyl phosphate and the residual organic peroxide in the composite modifier to form a TPU-rubber-asphalt interface double cross-linking structure; extruding the mixture through a mold or injection molding, and then immersing it in a 10-15°C water bath for rapid cooling and solidification, with a cooling rate of ≥20°C / min, to prevent phase separation of the components; cutting the molded material into sheets or granules, placing it in an oven at 40-50°C for 2 hours, and removing surface moisture to a moisture content of ≤0.1%, thereby obtaining a composite organic asphalt for a net-drainage type wing wall anti-seepage wall tooth groove water-stopping structure.

[0154] Example 5

[0155] A composite organic asphalt (5#) for a clean-drainage wing wall anti-seepage wall tooth groove water-stopping structure. The composite modified asphalt is used for the wing wall anti-seepage wall tooth groove water-stopping structure and comprises the following components in parts by weight:

[0156]

[0157] The preparation method of the composite modified product comprises the following steps: drying a thermoplastic polyurethane elastomer (TPU) to a moisture content of ≤0.05%; premixing carboxyl-modified natural rubber powder with a titanate coupling agent and a silane coupling agent so that the coupling agent uniformly covers the surface of the rubber powder; adding the dried TPU, premixed rubber powder, an organic peroxide crosslinking agent, and an anti-aging agent into a high-speed mixer and mixing them uniformly; feeding the mixture into a twin-screw extruder, utilizing shear force to promote melt blending, while the organic peroxide decomposes to induce mild crosslinking between the TPU and the rubber powder; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of approximately 3 mm; drying the particles in an oven at 60°C for 2 to 4 hours to ensure that the moisture content is ≤0.05%, and storing them in a sealed container away from light to obtain the composite modified product.

[0158] Among them, natural asphalt is lake asphalt.

[0159] The composite modified material includes the following components in parts by mass:

[0160] 30 parts thermoplastic polyurethane elastomer

[0161] 64 parts of modified natural rubber powder

[0162] 4 parts of titanate coupling agent and silane coupling agent

[0163] 0.3 parts of organic peroxide crosslinking agent

[0164] 1 part anti-aging agent.

[0165] The organic peroxide crosslinking agent is dicumyl peroxide.

[0166] The antioxidant is hindered phenol.

[0167] Modified natural rubber powder is processed mechanically or freeze-milled to a target particle size of 80 mesh and then screened to ensure uniform particle size. The surface of the rubber powder is carboxylated using an oxidizing agent such as potassium permanganate or hydrogen peroxide while controlling the temperature. Unreacted reagents are removed by washing, and the modified natural rubber powder is then vacuum-dried.

[0168] A method for preparing composite modified asphalt includes the following steps.

[0169] (1) processing natural rubber powder by mechanical pulverization or freeze pulverization technology to a target particle size of 80 mesh, and sieving to ensure particle size uniformity; using an oxidant to perform surface carboxylation treatment on the rubber powder, wherein the oxidant is selected from potassium permanganate or hydrogen peroxide, and the temperature is controlled in the range of 30° C. to 60° C. during the reaction; washing the reacted rubber powder to remove unreacted oxidant, and then drying under vacuum conditions to a moisture content of ≤0.5%, thereby obtaining 64.4 parts by mass of modified natural rubber powder;

[0170] (2) drying the thermoplastic polyurethane elastomer (TPU) to a water content of ≤0.1%; premixing the modified natural rubber powder prepared in step 1 with a coupling agent to form a rubber powder-coupling agent mixture; adding 30 parts by mass of the dried TPU, 32 parts by mass of the pretreated rubber powder-coupling agent mixture, 0.3 parts by mass of an organic peroxide crosslinking agent, and 1 part by mass of an anti-aging agent to a high-speed mixer, and mixing them at 3000 r / min for 10 minutes until uniform; feeding the mixture into a twin-screw extruder, and melt-blending at a temperature of 160-180°C and a speed of 200 r / min, using shear force to promote interfacial bonding; cooling the extruded material in a water tank and then pelletizing it to obtain composite particles with a diameter of about 3 mm; drying the particles in a 60°C oven for 2-4 hours to ensure that the water content is ≤0.05%, and storing them in a sealed, dark-proof manner for later use, thereby obtaining a composite modified product;

[0171] (3) 64.4 parts by mass of natural asphalt were heated to a molten state, and 32 parts by mass of the composite modifier prepared in step 2, 0.7 parts by mass of synthetic phenols, 0.2 parts by mass of benzophenone, 8 parts by mass of cyclohexane oil, and 0.6 parts by mass of trimethyl phosphate crosslinking agent were added in sequence, and mixed in stages: in the first stage, stirring at 140°C and 500 r / min for 20 minutes was performed to achieve preliminary dispersion; in the second stage, the temperature was raised to 160°C and high-speed shearing was performed at 1000 r / min for 40 minutes to promote component homogenization;

[0172] (4) Maintaining the temperature at 170-180°C at the end of the mixing process, a synergistic cross-linking reaction occurs between trimethyl phosphate and the residual organic peroxide in the composite modifier to form a TPU-rubber-asphalt interface double cross-linking structure; extruding the mixture through a mold or injection molding, and then immersing it in a 10-15°C water bath for rapid cooling and solidification, with a cooling rate of ≥20°C / min, to prevent phase separation of the components; cutting the molded material into sheets or granules, placing it in an oven at 40-50°C for 2 hours, and removing surface moisture to a moisture content of ≤0.1%, thereby obtaining a composite organic asphalt for a net-drainage type wing wall anti-seepage wall tooth groove water-stopping structure.

[0173] Experimental verification

[0174] The present invention statistically analyzes the improvement in performance indicators between traditional asphalt and the present invention's 1# to 5# composite organic asphalts as shown in the following table.

[0175]

[0176] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the scope of protection of the present invention.

Claims

1. A composite organic asphalt for a clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure, characterized by: The material components include the following parts by mass: 56-71.4 parts of natural asphalt; 22-32 parts of composite modified material; 6-8 parts of naphthenic oil; 0.4-0.6 parts of trimethyl phosphate crosslinking agent; Among them, the raw materials of the composite modified product are proportioned in parts by mass as follows: 20-30 parts of thermoplastic polyurethane elastomer; 55-65 parts of modified natural rubber powder; 2-4 parts of a mixture of a titanate coupling agent and a silane coupling agent; 0.3-0.5 parts of organic peroxide cross-linking agent; 0.5-1.0 parts of anti-aging agent.

2. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 1 is characterized by: The invention also comprises 0.5 to 0.7 parts of synthetic phenols and 0.2 to 0.3 parts of benzophenone.

3. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 2 is characterized by: The synthetic phenols are at least one of alkylated phenols and bisphenols.

4. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 1, characterized in that: The natural asphalt is at least one of lake asphalt, rock asphalt, ground asphalt and hard asphalt.

5. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 1 is characterized by: The modified natural rubber powder is surface carboxyl-modified natural rubber powder, and the target particle size is 80 meshes.

6. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 1, characterized in that: The organic peroxide cross-linking agent is at least one of dicumyl peroxide, benzoyl peroxide and lauroyl peroxide.

7. The composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 1 is characterized by: The anti-aging agent is at least one of hindered phenols and natural antioxidants.

8. A method for preparing a composite organic asphalt for a clean drainage type wing wall anti-seepage wall tooth groove water-stop structure, characterized by: The steps include: Step 1, preparing modified natural rubber powder: processing the unmodified natural rubber powder to a target particle size of 80 mesh by mechanical or freeze-crushing technology, and sieving; performing surface carboxyl modification treatment on the sieved unmodified natural rubber powder to obtain modified natural rubber powder; Step 2: preparing a composite modified product, comprising the following steps: Step 2-1, pretreating a mixture of modified natural rubber powder, a titanate coupling agent, and a silane coupling agent to form a rubber powder-coupling agent mixture; Step 2-2, drying the thermoplastic polyurethane elastomer; Step 2-3, mixing and melting the dried TPU, the rubber powder-coupling agent mixture, the organic peroxide crosslinking agent and the anti-aging agent to form a liquid composite modified product; Step 2-4, cooling, pelletizing and drying the liquid composite modified product to form a granular composite modified product; Step 3: The molten natural asphalt, the composite modifier, the synthetic phenols, the benzophenone, the cyclohexane oil and the trimethyl phosphate cross-linking agent are mixed in stages to obtain a composite organic asphalt.

9. The method for preparing the composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 8, characterized in that: In step 3, the preparation method of the composite organic asphalt includes the following steps: The natural asphalt is heated to 140-160°C to form a molten natural asphalt; The molten natural asphalt and naphthenic oil are mixed in one stage at 150-160°C to form a homogeneous asphalt matrix; The homogeneous asphalt matrix and the composite modifier are mixed in two stages at 170-180°C; First, synthetic phenols and benzophenone are added to the second-stage mixture in sequence and mixed evenly; then, trimethyl phosphate crosslinking agent is added and mixed evenly at 170-180°C to form a liquid composite organic asphalt with a TPU-rubber-asphalt interface crosslinking structure; The liquid composite organic asphalt is formed, cooled, cut and dried to obtain a solid composite organic asphalt.

10. The method for preparing the composite organic asphalt for the clean drainage type wing wall anti-seepage wall tooth groove water-stopping structure according to claim 8, characterized in that: In step 2-2, the moisture content of the thermoplastic polyurethane elastomer after drying must be less than 0.1%; in step 2-4, the moisture content of the granular composite modified product must be ≤0.05%.

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