Rubber-plastic-based long-acting toughening high-modulus agent for asphalt modification and preparation method thereof, and asphalt modification composition

Abstract

The invention discloses a rubber-plastic-based long-acting toughening high modulus agent for asphalt modification and a preparation method thereof, and an asphalt modification composition. The high modulus agent comprises desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber. The waste PET plastic is cracked and then polymerized with the ester and the nano organic montmorillonite; adding sulfur, dicumyl peroxide and a sulfydryl silane coupling agent; dioctyl phthalate and naphthenic oil are added; styrene-maleic anhydride copolymer and hydrogenated rosin glyceride; and a composite solvent. The preparation method comprises the following steps: adding the composite solvent, naphthenic oil and dioctyl phthalate, and heating; adding desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber, and stirring to fully swell; adding the styrene-maleic anhydride copolymer and the waste PET plastic cracking repolymerized ester, dispersing the ester, adding the nano organic montmorillonite, and continuing shearing; adding a sulfydryl silane coupling agent and hydrogenated rosin glyceride, and stirring to react under the protection of nitrogen; and adding sulfur and dicumyl peroxide, and shearing at a high speed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of road engineering materials, and particularly relates to an asphalt modified rubber-plastic based long-acting toughening high modulus agent and a preparation method thereof, and an asphalt modified composition. BACKGROUND

[0002] With the development of modern transportation towards heavy load and large flow, the high-temperature rutting resistance, low-temperature crack resistance and long-term fatigue resistance of asphalt pavement are put forward with unprecedented high standards. High modulus asphalt mixture is one of the effective ways to solve the problem of rutting, but the traditional high modulus agent often leads to the decrease of asphalt toughness, the brittleness of the material, and the deterioration of fatigue resistance and low temperature performance, which becomes the industry pain point.

[0003] In addition, the "black pollution" and "white pollution" caused by a large number of waste tires and plastics need to be solved urgently. Although the existing technology attempts to use rubber powder or plastic to modify asphalt, there are generally problems such as poor compatibility, single modification effect and easy aging attenuation. The fundamental reason is that simple physical blending is difficult to form a stable and durable micro-enhanced structure in asphalt.

[0004] Therefore, there is an urgent need in the art for a new technical solution that can organically combine the rigid and elastic advantages of rubber and plastic materials, not only achieving the balance between "high modulus" and "high toughness" in the macroscopic aspect, but also constructing a stable structure that can resist stress damage and aging effects for a long time in the microscopic aspect, so as to realize the overall leap of the performance of asphalt pavement. SUMMARY

[0005] The purpose of the present application is to provide an asphalt modified rubber-plastic based long-acting toughening high modulus agent to solve the problems of traditional asphalt modifier, such as difficult to balance modulus and toughness, insufficient fatigue resistance, poor compatibility with asphalt, poor durability, and ineffective use of solid waste. The rubber-plastic based modifier can significantly improve the high modulus, high toughness and long-acting fatigue resistance of asphalt mixture by constructing a multiple synergistic network structure.

[0006] Another purpose of the present application is to provide a preparation method of the asphalt modified rubber-plastic based long-acting toughening high modulus agent, which realizes the full reaction of each component and the controllable construction of multiple network structures through a multi-step wet process with precise control.

[0007] Still another purpose of the present application is to provide an asphalt modified composition containing the above-mentioned asphalt modified rubber-plastic based long-acting toughening high modulus agent.

[0008] The technical solution of the present application is: (I) An asphalt modified rubber-plastic based long-acting toughening high modulus agent, comprising the following raw materials by weight: Elastic network building components: 15-25 parts of desulfurized fine rubber powder, 5-10 parts of hydroxyl-terminated liquid cis-butadiene rubber; Plastic network and modulus-enhancing components: 8-15 parts of pyrolysis and repolymerization esterified waste PET plastic, 3-6 parts of nano-organic montmorillonite; Multiple cross-linking and activating components: 1-2 parts sulfur, 0.5-1.5 parts dicumyl peroxide, and 2-4 parts mercaptosilane coupling agent; Toughening and flexibility regulating components: 3-5 parts dioctyl phthalate, 10-15 parts naphthenic oil; In-situ polymerization and interface stabilizing components: 2-4 parts of styrene-maleic anhydride copolymer, 1-3 parts of hydrogenated rosin glycerol ester; Solvent and carrier: 30-50 parts of composite solvent.

[0009] Furthermore, the composite solvent is prepared by mixing aromatic oil and cracked oil in a mass ratio of 1:1.

[0010] Furthermore, the nano-organic montmorillonite is montmorillonite that has undergone organic quaternary ammonium salt intercalation treatment.

[0011] Furthermore, the mercaptosilane coupling agent is γ-mercaptopropyltrimethoxysilane.

[0012] Furthermore, the particle size of the desulfurized fine rubber powder is 80 mesh. (two) A method for preparing a rubber-plastic-based long-lasting toughening high-modulus agent for asphalt modification includes the following steps: A. Preconstruction and swelling of elastic network: Add the formulated amount of composite solvent, naphthenic oil and dioctyl phthalate to the reactor and heat to 90-110℃; add desulfurized fine rubber powder and hydroxyl-terminated liquid cis-butadiene rubber under low-speed stirring at 300-500 rpm, and maintain the temperature while stirring for 60-90 minutes to allow it to fully swell and form a pre-elastic network; B. Dispersion and intercalation of plastic components: Reduce the temperature of the system in step A to 70-85℃, add styrene-maleic anhydride copolymer and waste PET plastic pyrolysis and repolymerization ester, and shear at a medium speed of 500-800 rpm. After dispersion, add nano-organic montmorillonite and continue shearing for 30-45 minutes. C. Multiple crosslinking reaction: Raise the temperature of the system in step B to 130-150℃, add mercaptosilane coupling agent and hydrogenated rosin glycerol ester, and stir the reaction at 300-500 rpm for 30-40 minutes under nitrogen protection; then add sulfur and dicumyl peroxide, increase the stirring speed to 800-1200 rpm, and carry out high-speed shear crosslinking reaction for 1-2 hours; D. Cooling and purification: After the reaction is completed, the material is cooled to below 50℃, and unreacted impurities are removed by filtration to obtain the asphalt-modifying rubber-plastic-based long-acting toughening high-modulus agent.

[0014] Further, in step B, the nano-organic montmorillonite needs to be vacuum-dried at 105℃ for 2 hours before use.

[0015] Further, in step C, the sulfur and dicumyl peroxide need to be ground and passed through a 100-mesh sieve before use to ensure uniform dispersion. (Three) An asphalt-modifying composition comprises asphalt and the above asphalt-modifying rubber-plastic-based long-acting toughening high-modulus agent.

[0017] Further, the asphalt-modifying rubber-plastic-based long-acting toughening high-modulus agent is added in an amount of 4%-10% of the mass of the asphalt.

[0018] The beneficial effects of the present application are: 1. The asphalt modifier of the present application is designed with a triple synergistic network structure of "physical entanglement-chemical crosslinking-interface bonding" in asphalt modifier. It is a multi-level, integrated design from macroscopic mechanical support to microscopic energy dissipation. The detailed mechanism is as follows: (1) The physical entanglement network is mainly composed of desulfurization fine rubber powder and waste PET plastic pyrolysis re-polymerization ester. Among them, the elastomer network of desulfurization fine rubber powder forms physical entanglement points in asphalt, providing flexibility and basic toughness; while the long-chain molecules of waste PET plastic pyrolysis re-polymerization ester interpenetrate and entangle with the asphalt medium, forming a rigid physical skeleton; the two together build the first deformable and recoverable support network, laying the foundation for the initial rigidity and toughness of the material. (2) The chemical crosslinking network is formed by sulfur and dicumyl peroxide (DCP) and other crosslinking agents. They induce stable covalent bond connections (such as sulfur bridges or carbon-carbon bonds) between rubber powder or polymer molecular chains during high-temperature mixing, thus forming a stable three-dimensional network. This second network, like an internal "skeleton", greatly improves the overall performance of modified asphalt, including high-temperature resistance to flow (anti-permanent deformation) and long-term thermal stability. (3) The dynamic interface bonding network is the most precise third design, with styrene-maleic anhydride copolymer (SMA) and mercapto silane coupling agent as the core. The anhydride groups of SMA and the active groups of mercapto silane not only form strong chemical bonds (anchoring effect) with the polar components of asphalt and the surface of aggregate, but more importantly, they create a large number of reversible weak bonds (such as hydrogen bonds, coordination bonds) in the interface area. These weak bonds preferentially break when the material is subjected to external forces (such as stress caused by traffic load), efficiently converting mechanical energy into heat energy and dissipating it, thereby preventing the propagation of microcracks; once the external force is removed, these bonds can partially reversibly recombine, achieving a "self-healing" effect. This dynamic sacrificial mechanism significantly improves the damage tolerance and fatigue life of the material. The above three networks are not isolated, but deeply synergistic: the physical network is the load-bearing foundation, the chemical network provides stability, and the dynamic interface network plays a key role in stress buffering and energy dissipation between the two and at the interface with the asphalt matrix, together giving asphalt mixtures exceptional durability, crack resistance, and long-term performance retention, effectively delaying the occurrence of diseases such as pavement reflection cracks. This synergistic mechanism fundamentally solves the industry's difficult problem of balancing high modulus and high toughness, making the rut factor (76°C) of modified asphalt more than 300% higher than that of base asphalt, and the fatigue life more than 200% longer, achieving a breakthrough in performance.

[0019] 2. The invention builds a multi-level, multi-mechanism and functionally integrated "interface phase" rather than a simple physical contact surface through systematic engineering at the molecular level. The precision is specifically manifested as follows: first, at the chemical bonding level, a gradient bonding system composed of strong covalent bonds (provided by mercaptosilane coupling agent), medium-strong ion / coordination bonds (contributed by SMA anhydride groups) and dynamic reversible hydrogen bonds (formed by hydrogenated rosin glyceride and polar groups) is designed. This design enables the interface to ensure long-term structural stability through strong bonds and to preferentially break to dissipate energy when stressed by using dynamic sacrificial bonds, thereby greatly improving damage tolerance and fatigue resistance. Secondly, at the structural level, hydrogenated rosin glyceride is used as a "bridge molecule" to form a gradient layer on the surface of the SMA modifier, which continuously transitions the chemical composition and modulus from the polymer phase to the asphalt matrix, effectively relieving stress concentration and inhibiting the initiation and propagation of microcracks. Finally, the design has forward-looking long-term stability and self-healing potential, with chemical anchoring and antioxidant components slowing down interface aging, and dynamic hydrogen bond networks giving it certain post-damage self-repairing ability. This whole-chain systematic design from molecular functional group selection, gradient transition construction to long-term performance guarantee realizes the synergistic optimization of interface bonding strength, toughness and durability, which is the fundamental reason for the product to achieve ultra-high aging performance retention rate and excellent fatigue resistance life. The asphalt modifying rubber-plastic-based long-acting toughening high modulus agent of the invention has a stable triple network structure and precise interface design, so that the product has a performance retention rate of more than 85% after long-term aging, far exceeding conventional modifiers. The dynamic sacrificial bond mechanism significantly improves the damage tolerance of the material, greatly extends the fatigue resistance life of asphalt mixture, and effectively delays the occurrence of pavement reflection cracks and other diseases.

[0020] 3. The asphalt modifying rubber-plastic-based long-acting toughening high modulus agent of the invention uses a large amount of desulfurization fine rubber powder and waste PET plastic cracking repolymerized ester as the core raw material, realizes high value-added resource utilization of solid waste, meets the circular economy and sustainable development strategy, and significantly reduces the cost of raw materials.

[0021] 4. The present application produces the following synergistic effects through styrene-maleic anhydride copolymer, hydrogenated rosin glyceride and mercapto silane coupling agent: (1) Step-by-step improvement of compatibility: first step, hydrogenated rosin glyceride makes SMA preliminarily uniformly dispersed in asphalt through physical affinity and interface wetting; second step, mercapto silane coupling agent further "locks" the interface between the two phases through covalent bond on the basis of good dispersion. (2) Formation of "physical-chemical" double stable structure: hydrogenated rosin glyceride provides physical compatibilization (polarity matching, interface wetting), mercapto silane provides chemical bonding (covalent anchoring), both complement each other, solving the problem of insufficient stability of single method. (3) Synergistic improvement of long-term performance: SMA provides persistent high modulus, hydrogenated rosin glyceride maintains dispersion stability, and mercapto silane coupling agent resists phase separation caused by heat, shear and aging through chemical bond, all of which together ensure the performance uniformity and durability of modified asphalt during storage, transportation and use. Thus, the compatibility of the rubber and plastic-based long-acting toughening and high modulus agent for asphalt modification with asphalt is greatly improved, phase separation during storage and use is prevented, and the long-term stability and uniformity of product performance are ensured.

[0022] 5. The "step-by-step" wet preparation process of the rubber and plastic-based long-acting toughening and high modulus agent for asphalt modification adopted by the present application ensures the ordered and sufficient construction of each network structure through precise control of temperature, shear rate and feeding sequence, has strong controllability in production process, stable quality between batches, and is suitable for large-scale industrial production.

[0023] 6. The product of the rubber and plastic-based long-acting toughening and high modulus agent for asphalt modification is a uniform liquid preparation, which is uniformly and conveniently mixed with asphalt without special equipment. Its excellent performance can significantly prolong the service life of asphalt pavement, reduce the maintenance cost of the whole life cycle, and has huge comprehensive economic and social benefits. DETAILED DESCRIPTION

[0024] The present application will be further described in detail through specific embodiments.

[0025] In the following examples, the main raw materials used are as follows: desulfurized fine rubber powder (80 mesh) is purchased from Shandong Longli New Material Co., Ltd. or Anhui Blue Sky Recycling Resource Co., Ltd.; hydroxyl-terminated liquid butadiene rubber is purchased from Sinopec Yueyang Petrochemical Co., Ltd. or Jinzhou Petrochemical Co., Ltd.; waste PET plastic pyrolysis repolymerization esterification product is purchased from Jiangsu Meijing Petrochemical Co., Ltd. or Guangdong Jinfa Technology Co., Ltd.; nano organic montmorillonite (intercalated with organic quaternary ammonium salt) is purchased from Zhejiang Fenghong New Material Co., Ltd. or Beijing Huayu Technology Co., Ltd.; γ-mercaptopropyl trimethoxysilane is purchased from Nanjing Chen Gong Organic Silicon Material Co., Ltd. or Hubei Xinlantian New Material Co., Ltd.; styrene-maleic anhydride copolymer is purchased from American Kraton Polymer Co., Ltd. or Shanghai Rizhisheng Technology Co., Ltd.; hydrogenated rosin glyceride is purchased from Guangdong Kemao Linchan Chemical Co., Ltd. or Guangxi Kowara Chemical Industry Co., Ltd.; aromatic oil is purchased from PetroChina Karamay Petrochemical Co., Ltd.; cracking oil is purchased from Shandong Dongming Petrochemical Group Co., Ltd. Example 1,

[0026] An asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent, comprising the following raw materials by weight: (1) Elastic network building component: desulfurized fine rubber powder (80 mesh) 15 parts, hydroxyl-terminated liquid butadiene rubber 5 parts; (2) Plastic network and modulus enhancing component: waste PET plastic pyrolysis repolymerization esterification product 8 parts, nano organic montmorillonite 3 parts; (3) Multiple crosslinking and activation component: sulfur 1 part, dicumyl peroxide 0.5 part, γ-mercaptopropyl trimethoxysilane 2 parts; (4) Toughening and flexibility adjusting component: dioctyl phthalate 3 parts, naphthenic oil 10 parts; (5) In-situ polymerization and interface stabilization component: styrene-maleic anhydride copolymer 2 parts, hydrogenated rosin glyceride 1 part; (6) Solvent and carrier: composite solvent 30 parts (aromatic oil 15 parts, cracking oil 15 parts).

[0027] Preparation method: A. Elastic network pre-construction and swelling: add the formula amount of composite solvent, naphthenic oil and dioctyl phthalate to the reaction kettle, heat to 90℃; add desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber under low speed stirring at 300 rpm, keep the temperature and stir for 60 minutes to make it fully swell and form a pre-elastic network; B. Plastic component dispersion and intercalation: reduce the temperature of the system in step A to 70℃, add styrene-maleic anhydride copolymer and waste PET plastic pyrolysis repolymerization esterification product, shear at a medium speed of 500 rpm, after it is basically dispersed, add nano organic montmorillonite dried at 105℃ for 2 hours, continue to shear for 30 minutes; C. Multiple cross-linking reaction: the temperature of the system of step B is raised to 130°C, γ-mercaptopropyl trimethoxysilane and hydrogenated rosin glyceride are added, and the reaction is stirred at a speed of 300 rpm under nitrogen protection for 30 minutes; then sulfur and dicumyl peroxide ground and passed through a 100 mesh screen are added, and the stirring speed is increased to 800 rpm, and a high-speed shear cross-linking reaction is carried out for 1 hour; D. Cooling and purification: after the reaction is completed, the material is cooled to 50°C, and unreacted impurities are removed by filtration to obtain a long-acting toughening high modulus agent.

[0028] An asphalt modification composition comprises a base asphalt (SK70) and the above-mentioned asphalt modification rubber-plastic-based long-acting toughening high modulus agent, and the addition amount of the asphalt modification rubber-plastic-based long-acting toughening high modulus agent is 4.5% of the mass of the base asphalt. Example 2,

[0029] An asphalt modification rubber-plastic-based long-acting toughening high modulus agent comprises the following raw materials by weight: (1) Elastic network building component: fine rubber powder (80 mesh) 20 parts, hydroxyl-terminated liquid butadiene rubber 8 parts; (2) Plastic network and modulus enhancement component: waste PET plastic pyrolysis repolymerization esterification product 10 parts, nano organic montmorillonite 5 parts; (3) Multiple cross-linking and activation component: sulfur 1.5 parts, dicumyl peroxide 1.0 part, γ-mercaptopropyl trimethoxysilane 3 parts; (4) Toughening and flexibility adjusting component: dioctyl phthalate 4 parts, naphthenic oil 12 parts; (5) In-situ polymerization and interface stabilization component: styrene-maleic anhydride copolymer 2 parts, hydrogenated rosin glyceride 3 parts; (6) Solvent and carrier: composite solvent 50 parts (aromatic oil 25 parts, cracking oil 25 parts).

[0030] Preparation method: A. Elastic network pre-construction and swelling: add the formula amount of composite solvent, naphthenic oil and dioctyl phthalate to the reaction kettle, and heat to 100°C; add desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber under low-speed stirring at 400 rpm, maintain the temperature and stir for 75 minutes to make it fully swell and form a pre-elastic network; B. Plastic component dispersion and intercalation: the temperature of the system of step A is reduced to 80°C, styrene-maleic anhydride copolymer and waste PET plastic pyrolysis repolymerization esterification product are added, and medium-speed shearing is carried out at a speed of 700 rpm, after it is basically dispersed, nano organic montmorillonite dried at 105°C for 2 hours is added, and shearing is continued for 40 minutes; C. Multiple cross-linking reaction: the temperature of the system of step B is raised to 140°C, γ-mercaptopropyl trimethoxysilane and hydrogenated rosin glyceride are added, and the reaction is stirred at a speed of 400 rpm under nitrogen protection for 30 minutes; then sulfur and dicumyl peroxide ground and passed through a 100 mesh screen are added, the stirring speed is increased to 1000 rpm, and high-speed shear cross-linking reaction is carried out for 1.5 hours; D. Cooling and purification: after the reaction is completed, the material is cooled to 50°C, and unreacted impurities are removed by filtration to obtain a long-acting toughening high modulus agent.

[0031] A bitumen modified composition comprising a base bitumen (SK70) and the above-mentioned bitumen modified rubber-plastic based long-acting toughening high modulus agent, the addition amount of the bitumen modified rubber-plastic based long-acting toughening high modulus agent is 4.5% of the mass of the base bitumen. Example 3,

[0032] A bitumen modified rubber-plastic based long-acting toughening high modulus agent, comprising the following raw materials by weight: (1) Elastic network building component: desulfurized fine rubber powder (80 mesh) 25 parts, hydroxyl-terminated liquid butadiene rubber 10 parts; (2) Plastic network and modulus enhancement component: waste PET plastic pyrolysis repolymerized esterified product 15 parts, nano organic montmorillonite 6 parts; (3) Multiple cross-linking and activation component: sulfur 2 parts, dicumyl peroxide 1.5 parts, γ-mercaptopropyl trimethoxysilane 4 parts; (4) Toughening and flexibility adjusting component: dioctyl phthalate 5 parts, naphthenic oil 15 parts; (5) In-situ polymerization and interface stabilization component: styrene-maleic anhydride copolymer 4 parts, hydrogenated rosin glyceride 3 parts; (6) Solvent and carrier: composite solvent 50 parts (aromatic oil 25 parts, pyrolysis oil 25 parts).

[0033] Preparation method: A. Elastic network pre-construction and swelling: add the formula amount of composite solvent, naphthenic oil and dioctyl phthalate in the reaction kettle, and heat to 110°C; add desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber under low-speed stirring at 500 rpm, maintain the temperature and stir for 90 minutes to make it fully swell and form a pre-elastic network; B. Plastic component dispersion and intercalation: the temperature of the system of step A is reduced to 85°C, styrene-maleic anhydride copolymer and waste PET plastic pyrolysis repolymerized esterified product are added, and medium-speed shear is carried out at a speed of 800 rpm; after it is basically dispersed, nano organic montmorillonite dried at 105°C for 2 hours is added, and shear is continued for 45 minutes; C. Multiple crosslinking reaction: the temperature of the system of step B is raised to 150°C, γ-mercaptopropyl trimethoxysilane and hydrogenated rosin glyceride are added, and the reaction is stirred at 500 rpm under nitrogen protection for 40 minutes; then sulfur and dicumyl peroxide ground and passed through a 100 mesh screen are added, and the stirring speed is raised to 1200 rpm, and high speed shearing crosslinking reaction is carried out for 2 hours; D. Cooling and purification: after the reaction is completed, the material is cooled to 50°C, and unreacted impurities are removed by filtration to obtain a long-acting toughening high modulus agent.

[0034] An asphalt modified composition comprises a base asphalt (SK70) and the above-mentioned asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent, and the addition amount of the asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent is 4.5% of the mass of the base asphalt. Example 4,

[0035] The difference between this example and example 1 is that in the asphalt modified composition, the addition amount of the asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent is 4.0% of the mass of the base asphalt. Example 5,

[0036] The difference between this example and example 1 is that in the asphalt modified composition, the addition amount of the asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent is 10.0% of the mass of the base asphalt.

[0037] SBS modified asphalt (the addition amount of the modifier is 4.5% of the mass of the base asphalt) is selected as comparative example 1, and the performance of the asphalt modified composition prepared in examples 1-5 is tested and compared. Table 1 below is the test results of the conventional performance of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt; Table 2 is the test results of the rheological properties of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt; Table 3 is the test results of the long-term performance of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt; Table 4 is the test results of the basic performance of the mixture of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt mixture; Table 5 is the test results of the high temperature performance of the mixture of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt mixture; Table 6 is the test results of the four-point fatigue bending test of the mixture of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt mixture; and Table 7 is the test results of the dynamic modulus test (MPa) of the mixture of the modified asphalt (i.e. the asphalt modified composition) in comparative example 1 and examples 1-5 and the base asphalt mixture.

[0038] Table 1

[0039] Table 2

[0040] Table 3

[0041] Table 4

[0042] Table 5

[0043] Table 6

[0044] Table 7

[0045] Based on the comprehensive analysis of the data in Tables 1 to 7, the rubber-plastic-based long-acting toughening high-modulus agent for asphalt modification of the present application exhibits overall performance advantages. In terms of asphalt, it actually exhibits a synergistic improvement in high-temperature rutting resistance and fatigue resistance. In terms of the mixture, the dynamic stability of Example 1 is 12580 times / mm, which is 2.8 times that of Comparative Example 1; the four-point bending fatigue life is improved by 2.8-3.5 times under the same strain; the dynamic modulus is improved by 30-90% in the full temperature range, especially under high-temperature low-frequency conditions. Based on the benchmark performance of Example 1, the performance of Example 4 (addition amount 4%) is slightly lower than that of Example 1, and the performance of Example 5 (addition amount 10%) is significantly better than that of Example 1, which reflects the positive effect of the addition amount on the asphalt modification effect. All the data are consistent with the general performance rules of asphalt materials and consistent with existing data trends. These data verify the unique advantages of the "physical entanglement-chemical crosslinking-interface bonding" triple network structure in realizing the unification of high modulus and high toughness, and also reflect excellent durability and temperature stability.

Claims

1. A rubber-plastic based long-acting toughening high modulus agent for asphalt modification, characterized by: The raw materials include the following weight parts: desulfurized fine rubber powder 15-25 parts, hydroxyl-terminated liquid butadiene rubber 5-10 parts; waste PET plastic pyrolysis repolymerization esterification product 8-15 parts, nano organic montmorillonite 3-6 parts; sulfur 1-2 parts, dicumyl peroxide 0.5-1.5 parts, mercapto silane coupling agent 2-4 parts; dioctyl phthalate 3-5 parts, naphthenic oil 10-15 parts; styrene-maleic anhydride copolymer 2-4 parts, hydrogenated rosin glyceride 1-3 parts; composite solvent 30-50 parts.

2. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 1, characterized in that: The composite solvent is compounded from aromatic oil and cracking oil at a mass ratio of 1:

1.

3. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 1, characterized in that: The nano organic montmorillonite is montmorillonite treated by intercalation of organic quaternary ammonium salt.

4. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 1, characterized in that: The mercapto silane coupling agent is γ-mercaptopropyl trimethoxysilane.

5. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 1, characterized in that: The desulfurized fine rubber powder has a particle size of 80 mesh.

6. A process for the preparation of the rubber-plastic based long-lasting toughening high modulus agent for bitumen modification according to any one of claims 1-5, characterized by, The method includes the following steps: A. Elastic network pre-construction and swelling: adding the formula amount of composite solvent, naphthenic oil and dioctyl phthalate in a reaction kettle, heating to 90-110℃; adding desulfurized fine rubber powder and hydroxyl-terminated liquid butadiene rubber under low-speed stirring at 300-500 rpm, maintaining the temperature and stirring for 60-90 minutes to make it fully swell and form a pre-elastic network; B. Plastic component dispersion and intercalation: reducing the temperature of the system of step A to 70-85℃, adding styrene-maleic anhydride copolymer and waste PET plastic pyrolysis repolymerization esterification product, shearing at a medium speed of 500-800 rpm, adding nano organic montmorillonite after dispersion, and continuing shearing for 30-45 minutes; C. Multiple crosslinking reaction: increasing the temperature of the system of step B to 130-150℃, adding mercapto silane coupling agent and hydrogenated rosin glyceride, stirring at a speed of 300-500 rpm under nitrogen protection for 30-40 minutes; then adding sulfur and dicumyl peroxide, increasing the stirring speed to 800-1200 rpm, and performing high-speed shearing crosslinking reaction for 1-2 hours; D. Cooling and purification: after the reaction is completed, cooling the material to below 50℃, removing unreacted impurities by filtration, and obtaining the asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent.

7. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 6, characterized in that: In step B, the nano organic montmorillonite needs to be vacuum dried at 105℃ for 2 hours before use.

8. The rubber-plastic based long-acting toughening high modulus agent for asphalt modification according to claim 6, characterized in that: In step C, the sulfur and dicumyl peroxide need to be ground and passed through a 100 mesh sieve before use.

9. A bitumen modifying composition characterised in that: The asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent of any one of claims 1-5.

10. The asphalt-modifying composition of claim 9, wherein: The addition amount of the asphalt-modifying rubber-plastic-based long-acting toughening high modulus agent is 4%-10% of the mass of the asphalt.

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