Three-step method environment-friendly SBS modified asphalt regenerant as well as preparation method and application thereof

Abstract

The invention discloses a three-step method environment-friendly SBS modified asphalt regenerant as well as a preparation method and application thereof, and relates to the field of regeneration of waste road engineering materials. The regenerant is prepared from the following components in parts by mass: 50-70 parts of bio-oil, 40-60 parts of desulfurized rubber, 3-9 parts of a cross-linking agent, 1-2 parts of an antioxidant and 1-2 parts of a photoaging inhibitor. The environment-friendly three-step method SBS modified asphalt regenerant is prepared through wetting, dispersing and stabilizing processes.

Description

Technical Field

[0001] The invention belongs to the technical field of road asphalt material regeneration, and specifically relates to a three-step environmentally friendly SBS modified asphalt regeneration agent and a preparation method and application thereof. Background Art

[0002] Asphalt pavement regeneration technology is an effective means to achieve the reuse of waste pavement milling materials. The choice of regeneration agent directly affects the final regeneration effect. At present, the common regeneration agents on the market are mostly chemical synthetic materials based on petroleum products. Although they have a good recovery effect on aged asphalt, they inevitably bring about problems of resource consumption and environmental pollution. With the enhancement of environmental awareness and the demand for sustainable utilization of resources, the development of green regeneration agents based on renewable resources and waste materials has become a new research direction.

[0003] Vegetable oils such as epoxidized soybean oil and rapeseed oil are renewable and biodegradable, which to a certain extent improves the environmental protection issues of traditional mineral oil-based regeneration agents. However, the chemical structure of vegetable oil molecules is relatively simple. Although they can supplement the missing light oil in asphalt, they cannot deeply repair the molecular structure fractures and cross-linking of aged asphalt, resulting in limited regeneration effects. High molecular polymer regeneration agents can improve the elasticity and crack resistance of regenerated asphalt, but their compatibility with the asphalt matrix is ​​often a problem. Since high molecular polymers are not easy to mix evenly with asphalt, regeneration agents are prone to uneven dispersion or separation in asphalt, resulting in unstable regeneration effects. In addition, these polymer materials are mostly synthetic materials, and the production process involves a large number of chemical synthesis steps, which brings environmental burdens, and the material cost is high, which limits their wide application. Summary of the invention

[0004] In view of the shortcomings of vegetable oil regeneration agents and high molecular polymer regeneration agents as asphalt modifiers in the prior art, the present invention provides a three-step environmentally friendly SBS modified asphalt regeneration agent and its preparation method and application. The present invention uses bio-oil, desulfurized rubber, cross-linking agent, antioxidant aging agent, and anti-light aging agent as raw materials to prepare the SBS modified asphalt regeneration agent. The main components of the product are green, environmentally friendly and renewable, simple to prepare, low cost, and can effectively regenerate SBS modified asphalt of different aging degrees, slow down the secondary aging of the regenerated SBS modified asphalt, improve the high and low temperature performance of the regenerated asphalt, and solve the problem of poor durability of the regenerated asphalt.

[0005] The technical solution of the present invention is as follows: A three-step environmentally friendly SBS modified asphalt regeneration agent and its preparation method and application.

[0006] The components of the regeneration agent are composed of the following parts by weight: 50-70 parts of bio-oil, 40-60 parts of devulcanized rubber, 3-9 parts of cross-linking agent, 1-2 parts of antioxidant, and 1-2 parts of anti-light aging agent.

[0007] The bio-oil in the present invention is a green and renewable energy source, which is derived from the conversion of biomass materials and can significantly reduce greenhouse gas emissions, realize the sustainable utilization of resources and reduce environmental pollution; the desulfurized rubber is a waste rubber treated by technology to restore its plasticity and reuse it, which not only reduces environmental pollution, but also reduces energy consumption and production costs. The present invention prepares an environmentally friendly three-step SBS modified asphalt regeneration agent through wetting, dispersion and stabilization processes. During the wetting process, the interface between the desulfurized rubber particles and the particles is replaced by the interface between the particles and the bio-oil. During the dispersion process, the high-speed shearing machine breaks up the desulfurized rubber particles into smaller units, the surface area of ​​the broken particles increases, and the particles are prone to generate mutually attractive van der Waals forces, which destroys the dispersion effect. During the stabilization process, the cross-linking agent is added and adsorbed on the particle surface, which reduces the interfacial tension between the solid and the liquid, effectively prevents the agglomeration of the colloidal particles, and improves the dispersion efficiency of the desulfurized rubber particles. The addition of anti-light and anti-oxidation aging agents further improves the stability of the present invention in practical engineering applications.

[0008] The purpose of the present invention is achieved through the following technical solutions: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: S1. Raw material preparation: prepare the following raw materials by mass: 50-70 parts of bio-oil, 40-60 parts of devulcanized rubber, 3-9 parts of cross-linking agent, 1-2 parts of antioxidant, and 1-2 parts of anti-light aging agent; The bio-oil is one or a combination of soybean oil, rapeseed oil, palm oil, kitchen waste oil and their derivative oils, and the mixture can be in any proportion; The raw materials of devulcanized rubber come from one or a combination of natural rubber (NR), styrene-butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), and nitrile rubber (NBR), and the mixture can be in any proportion; The crosslinking agent is one of maleic anhydride, maleic anhydride grafted SEBS, and maleic anhydride grafted tackifying resin; The antioxidant is one of the amine antioxidants such as N-phenyl-α-naphthylamine (antioxidant A), N-isopropyl-N'-phenyl-p-phenylenediamine (antioxidant 4010NA), N,N'-di-sec-butyl-p-phenylenediamine (antioxidant 4020), diphenylamine, and p-aminodiphenylamine; The anti-photoaging agent is one or a combination of ultraviolet absorbers and light stabilizers, and the mixture can be in any proportion; The ultraviolet absorber is one of benzophenone ultraviolet absorbers such as 2-hydroxy-4-methoxybenzophenone (UV-9), 2,6-dimethylbenzotriazole (UV-328), 2-(2'-hydroxy-5'-methylphenyl)benzotriazole (UV-P), and the like; The light stabilizer is one of the hindered amine light stabilizers such as bis(2,2,6,6-tetramethyl-4-piperidinyl) adipate (Tinuvin 770), poly(4-methyl-2,6-dipentyl) piperidine succinate (Tinuvin 622), bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 292); S2. The preparation of SBS modified asphalt regeneration agent includes the following steps: S2-1, adding desulfurized rubber to bio-oil, stirring and mixing, and keeping the mixture at 135° C. for 30 to 60 minutes to achieve wetting of solid particles in the liquid phase, to obtain a mixture A1; S2-2, shearing the mixture A1 at 160° C. and 4000 rpm for 30 to 60 min using a high-speed shearing machine to achieve deagglomeration and dispersion of solid particle agglomerates to obtain a mixture A2; S2-3, adding a crosslinking agent to the mixture A2, and shearing the mixture A1 with a high-speed shearing machine at 160° C. and a rotation speed of 4000 rpm for 30 to 60 min to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3; S2-4, adding a light aging inhibitor and an antioxidant to the mixture A3, stirring the mixture A3 at 160° C. and 1500 rpm for 60 to 90 min using a stirrer to achieve anti-aging and stability of the slurry, to obtain a mixture A4; S2-5. Place the mixture A4 in a constant temperature box at 135°C for 30 to 60 minutes to obtain a three-step environmentally friendly SBS modified asphalt regeneration agent. Add the prepared three-step environmentally friendly SBS modified asphalt regeneration agent to the aged SBS modified asphalt in an amount of 4% to 20% by mass. After stirring evenly, the prepared regenerated SBS modified asphalt has the following performance indicators: needle penetration (0.1mm) is 44.2-46.8; elongation at 5°C is 28.4 cm -31.1 cm; softening point is 60.4°C-62.7°C; viscosity at 135°C is 2186 mPa•s-2280 mPa•s.

[0009] In the present invention: Furthermore, the raw material preparation described in S1 is to prepare the following raw materials in parts by mass: 60 parts of bio-oil, 50 parts of devulcanized rubber, 6 parts of cross-linking agent, 1.5 parts of antioxidant and 1.5 parts of anti-light aging agent.

[0010] The important role of bio-oil is component regulation, which replenishes the light components lost during asphalt aging and realizes the regeneration of aged asphalt matrix.

[0011] The desulfurization process of desulfurized rubber is physical desulfurization or chemical desulfurization, with a degree of more than 50%.

[0012] Cross-linking agents, also known as stabilizers, link SBS molecules and devulcanized rubber particles in the regeneration agent system.

[0013] Devulcanized rubber and stabilizer work together to achieve the regeneration of aged and broken SBS.

[0014] The preparation principle of the three-step environmentally friendly SBS modified asphalt regeneration agent described in S2 is as follows: In the process of preparing the regeneration agent, the present invention prepares an environmentally friendly three-step SBS modified asphalt regeneration agent through wetting, dispersing and stabilizing processes: During the wetting process, the interface between the devulcanized rubber particles is replaced by the interface between the particles and the bio-oil. The degree of wetting is the premise for whether the powder can be evenly dispersed. Poor wetting will cause agglomeration and caking, which will affect further dispersion and mixing. During the dispersion process, the high-speed shearing machine breaks up the devulcanized rubber particles into smaller units. The surface area of ​​the broken particles increases, and the particles are prone to generate mutually attractive van der Waals forces. If destabilized, these particles will re-aggregate into agglomerates, destroying the dispersion effect. During the stabilization process, the crosslinking agent is added and adsorbed on the particle surface, reducing the interfacial tension between the solid and the liquid, effectively preventing the agglomeration of the colloidal particles, and improving the dispersion efficiency of the devulcanized rubber particles. The addition of the two anti-aging agents can further improve the stability of the present invention in practical engineering applications.

[0015] The present invention also relates to a three-step environmentally friendly SBS modified asphalt regeneration agent, which is obtained by the preparation method of the above-mentioned three-step environmentally friendly SBS modified asphalt regeneration agent. The prepared three-step environmentally friendly SBS modified asphalt regeneration agent can realize the dual regeneration of asphalt matrix and SBS modifier in an aged SBS modified asphalt system. The prepared three-step environmentally friendly SBS modified asphalt regeneration agent is added to the aged SBS modified asphalt in an amount of 4% to 20% by mass, and after uniform stirring, the prepared regenerated SBS modified asphalt has the following performance indicators: needle penetration (0.1mm) is 44.2-46.8; elongation at 5°C is 28.4cm -31.1 cm; softening point is 60.4°C-62.7°C; viscosity at 135°C is 2186 mPa•s-2280 mPa•s.

[0016] The present invention also relates to an application of a three-step environmentally friendly SBS modified asphalt regeneration agent. The prepared three-step environmentally friendly SBS modified asphalt regeneration agent is added to aged SBS modified asphalt in an amount of 4% to 20% by mass. The aged SBS modified asphalt and the three-step environmentally friendly SBS modified asphalt regeneration agent are uniformly stirred in a stirrer under heating conditions of 145° C. to 165° C., the stirring speed is 800 rpm to 1500 rpm, and the stirring time is 30 min to 60 min. Regenerated SBS modified asphalt is prepared for use in road engineering.

[0017] Furthermore, the aged SBS modified asphalt is any one of thin film aged asphalt (TFOT), rotary thin film aged asphalt (RTFOT), ultraviolet aged asphalt (UV), pressure aged asphalt (PAV), waste extraction aged asphalt, and any mixture of any proportion of multiple thereof.

[0018] Furthermore, the heating condition is preferably 155°C.

[0019] Furthermore, the stirring speed of the stirrer is preferably 1000 rpm, and the stirring time is preferably 45 min.

[0020] Compared with the prior art, the present invention has the following advantages: 1. The three-step environmentally friendly SBS modified asphalt regeneration agent described in the present invention has environmentally friendly and renewable raw materials. The main component of the present invention, bio-oil, as a green and renewable energy source, is derived from the conversion of biomass materials, which can significantly reduce greenhouse gas emissions, achieve sustainable utilization of resources and reduce environmental pollution; while the desulfurized rubber uses technology to treat waste rubber to restore its plasticity and reuse it, which not only reduces environmental pollution, but also reduces energy consumption and production costs. The combination of these two main components not only promotes green production and reduces environmental pollution, but also promotes the development of the circular economy. It is used for the regeneration of waste asphalt to achieve the purpose of "waste by waste", and realizes the maximum utilization of waste resources and the minimum emission of waste.

[0021] 2. The three-step environmentally friendly SBS modified asphalt regeneration agent described in the present invention is a dual regeneration of asphalt and polymer. During the aging process of SBS modified asphalt, the light components in the asphalt matrix are converted into macromolecular components such as asphaltene. Under the influence of ultraviolet or thermal oxidation aging, the molecular chain of the SBS polymer breaks, resulting in the performance degradation of the SBS modified asphalt. The bio-oil in the regeneration agent described in the present invention can supplement the light components missing in the asphalt matrix. At the same time, the light components in the asphalt and the bio-oil will diffuse into the desulfurized rubber particles, causing them to swell. Since the three-dimensional structure of the desulfurized rubber powder is destroyed, the rubber light molecules will be released when it comes into contact with asphalt and bio-oil under the cross-linking action of the cross-linking agent. Therefore, the desulfurized rubber particles can be re-cross-linked with the SBS network structure to form a new three-dimensional network structure, thereby realizing the dual regeneration of SBS modified asphalt.

[0022] 3. The three-step environmentally friendly SBS modified asphalt regeneration agent described in the present invention has good dispersion and stability. In the regeneration agent system prepared by the present invention, bio-oil and cross-linking agent are cross-linked with each other and surround the desulfurized rubber powder particles. The interface between desulfurized rubber particles and particles is replaced by the interface between particles and bio-oil and cross-linking agent. The cross-linking agent adheres to the surface of desulfurized rubber particles, reducing the interfacial tension between solid and liquid. At the same time, due to the steric barrier of the dispersant, the desulfurized rubber particles are not easy to approach at a certain distance, which effectively prevents the aggregation of colloidal particles and improves the dispersion efficiency of desulfurized rubber particles and the stability of the regeneration agent system.

[0023] 4. The three-step environmentally friendly SBS modified asphalt regeneration agent described in the present invention has multiple anti-aging capabilities. The regeneration agent prepared by the present invention realizes the multiple anti-aging capabilities of the regeneration agent by integrating desulfurized rubber, antioxidant aging agent and anti-ultraviolet aging agent. Desulfurized rubber itself has excellent anti-aging ability and provides a stable molecular structure foundation to effectively resist the erosion of the external environment; the antioxidant aging agent inhibits the oxidation reaction of active groups and molecular chains in rubber, SBS and asphalt, slowing down the aging rate; and the anti-ultraviolet aging agent prevents the destructive effect of ultraviolet rays on the asphalt matrix and other modifiers by absorbing or reflecting ultraviolet rays. These components work synergistically in the regeneration agent to jointly improve the anti-aging performance of rubber products, enabling them to maintain good performance and service life under a variety of environmental conditions.

[0024] 5. The three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent of the present invention has a simple preparation process and low cost. The three-step method for preparing the regeneration agent proposed in the present invention significantly simplifies the preparation process, realizes efficient production through carefully designed reaction steps, reduces the requirements for the professional skills of operators, and reduces energy consumption and waste generation, so that the cost of raw materials, energy and time costs, and waste treatment costs are effectively controlled, showing the dual advantages of simplified preparation process and low cost, and laying a solid foundation for product competitiveness and sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0026] Figure 1 This is a three-step preparation mechanism diagram of an environmentally friendly SBS modified asphalt regeneration agent of the present invention; Figure 2 This is a diagram verifying the application effect of a three-step environmentally friendly SBS modified asphalt regeneration agent of the present invention (showing the changes in the phase angle curves of the regenerated asphalt in the comparative example and the embodiment). DETAILED DESCRIPTION

[0027] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments, rather than limiting the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] A typical embodiment of the present invention provides a three-step environmentally friendly SBS modified asphalt regeneration agent, which is composed of the following parts by mass: 50-70 parts of bio-oil, 40-60 parts of devulcanized rubber, 3-9 parts of cross-linking agent, 1-2 parts of antioxidant, and 1-2 parts of anti-light aging agent.

[0031] Bio-oil is one or a combination of soybean oil, rapeseed oil, palm oil, kitchen waste oil and their derivative oils. The raw materials of desulfurized rubber come from one or a combination of natural rubber (NR), styrene-butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), nitrile rubber (NBR), and the desulfurization process of desulfurized rubber is physical desulfurization or chemical desulfurization, and the degree is more than 50%. The cross-linking agent is also called a stabilizer, which is one or a combination of maleic anhydride, maleic anhydride grafted SEBS, and maleic anhydride grafted tackifying resin.

[0032] The antioxidant is one or a combination of several amine antioxidants such as N-phenyl-α-naphthylamine (antioxidant A), N-isopropyl-N'-phenyl-p-phenylenediamine (antioxidant 4010NA), N,N'-di-sec-butyl-p-phenylenediamine (antioxidant 4020), diphenylamine, and p-aminodiphenylamine.

[0033] The anti-photoaging agent is one or a combination of ultraviolet absorbers and light stabilizers. The ultraviolet absorber is one or a combination of benzophenone ultraviolet absorbers such as 2-hydroxy-4-methoxybenzophenone (UV-9), 2,6-dimethylbenzotriazole (UV-328), 2-(2'-hydroxy-5'-methylphenyl)benzotriazole (UV-P) and other benzotriazole ultraviolet absorbers. The light stabilizer is one or a combination of hindered amine light stabilizers such as bis(2,2,6,6-tetramethyl-4-piperidinyl) adipate (Tinuvin 770), poly(4-methyl-2,6-dipentyl) piperidine succinate (Tinuvin 622), bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 292).

[0034] A typical embodiment of the present invention provides a method for preparing the above-mentioned environmentally friendly SBS modified asphalt regeneration agent, comprising the following steps: Add the desulfurized rubber to the bio-oil and stir and mix them thoroughly, keep the mixture at 135°C for 30min~60min to achieve wetting of solid particles in the liquid phase, and obtain a mixture A1; use a high-speed shearing machine to shear the mixture A1 at 160°C at a speed of 4000rpm for 30min~60min to achieve depolymerization and dispersion of solid particle agglomerates, and obtain a mixture A2; add a crosslinking agent to the mixture A2, and use a high-speed shearing machine to shear the mixture A1 at 160°C at a speed of 4000rpm for 30min~60min to achieve stabilization of the depolymerized slurry to prevent re-agglomeration, and obtain a mixture A3; add an anti-light aging agent and an anti-oxidation aging agent to the mixture A3, and use a stirrer to stir the mixture A3 at 160°C at a speed of 1500rpm for 60min~90min to achieve anti-aging and stability of the slurry, and obtain a mixture A4; place the mixture A4 in a constant temperature box at 135°C for 30min~60min to obtain an environmentally friendly SBS modified asphalt regeneration agent.

[0035] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in combination with specific embodiments and comparative examples.

[0036] Embodiment 1: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The composition and mass percentage of each raw material of the regeneration agent are as follows: 50% epoxidized soybean oil, 45% NR desulfurized rubber, 2% maleic anhydride grafted SEBS, 1% antioxidant 4010NA, 1% ultraviolet absorber UV-9, 1% light stabilizer Tinuvin 770; the preparation method is as follows: Add the devulcanized rubber into the epoxidized soybean oil, stir and mix thoroughly, and keep the mixture at 135° C. for 60 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-A; The mixture A1-A was sheared for 60 min at 160° C. and 4000 rpm using a high-speed shearing machine to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-A; A cross-linking agent was added to the mixture A2-A, and the mixture A2-A was sheared at 160° C. and 4000 rpm for 60 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-A; Adding a light aging inhibitor and an antioxidant to the mixture A3-A, stirring the mixture A3-A at 160° C. and 1500 rpm for 90 minutes using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-A; The mixture A4-A was placed in a thermostatic box at 135° C. for 60 minutes to obtain an environmentally friendly SBS modified asphalt regeneration agent AA.

[0037] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AA regenerated SBS modified asphalt.

[0038] Figure 1 This is a three-step preparation mechanism diagram of an environmentally friendly SBS modified asphalt regeneration agent according to Example 1, which provides a three-step process for preparing the regeneration agent of the present invention.

[0039] Embodiment 2: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The raw material composition and mass percentage of the regeneration agent are as follows: 50% rapeseed oil, 45% NR desulfurized rubber, 2% maleic anhydride grafted SEBS, 1% antioxidant 4020, 1% UV absorber UV-328, 1% light stabilizer Tinuvin 622; the preparation method is as follows: Add the desulfurized rubber into rapeseed oil, stir and mix thoroughly, and keep the mixture at 135° C. for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-B; The mixture A1-B was sheared for 30 min at 4000 rpm using a high-speed shearing machine at 160° C. to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-B; A cross-linking agent was added to the mixture A2-B, and the mixture A2-B was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-B; Adding a light aging inhibitor and an antioxidant to the mixture A3-B, stirring the mixture A3-B at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-B; The mixture A4-B was placed in a thermostatic box at 135° C. for 30 minutes to obtain an environmentally friendly SBS modified asphalt regeneration agent AB.

[0040] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AB regenerated SBS modified asphalt.

[0041] Embodiment 3: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The raw material composition and mass percentage of the regeneration agent are as follows: 25% epoxidized soybean oil, 25% rapeseed oil, 45% SBR desulfurized rubber, 2% maleic anhydride grafted SEBS, 1% antioxidant diphenylamine, 1% ultraviolet absorber UV-P, 1% light stabilizer Tinuvin 292. The preparation method is as follows: Add the desulfurized rubber to the epoxidized soybean oil and rapeseed oil, stir and mix thoroughly, and keep the mixture at 135° C. for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-C; The mixture A1-C was sheared for 30 min at 4000 rpm using a high-speed shearing machine at 160° C. to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-C; A cross-linking agent was added to the mixture A2-C, and the mixture A2-C was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-C; Adding a light aging inhibitor and an antioxidant to the mixture A3-C, stirring the mixture A3-C at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-C; The mixture A4-C was placed in a thermostatic box at 135° C. for 30 min to obtain an environmentally friendly SBS modified asphalt regeneration agent AC.

[0042] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AC regenerated SBS modified asphalt.

[0043] Embodiment 4: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The raw material composition and mass percentage of the regeneration agent are as follows: 50% palm oil, 45% SBR desulfurized rubber, 2% maleic anhydride, 1% antioxidant p-aminodiphenylamine, 0.5% ultraviolet absorber UV-9, 0.5%0.5% ultraviolet absorber UV-9, light stabilizer Tinuvin 770, 0.5% light stabilizer Tinuvin 292; the preparation method is as follows: Add the desulfurized rubber to the palm oil, stir and mix thoroughly, and keep the mixture at 135°C for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-D; The mixture A1-D was sheared for 30 min at 160° C. and 4000 rpm using a high-speed shearing machine to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-D; A cross-linking agent was added to the mixture A2-D, and the mixture A2-D was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-D; Adding a light aging inhibitor and an antioxidant to the mixture A3-D, stirring the mixture A3-D at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-D; The mixture A4-D was placed in a thermostatic box at 135° C. for 30 min to obtain an environmentally friendly SBS modified asphalt regeneration agent AD.

[0044] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AD regenerated SBS modified asphalt.

[0045] Embodiment 5: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The composition and mass percentage of each raw material of the regeneration agent are as follows: 20% epoxidized soybean oil, 30% palm oil, 45% SBR desulfurized rubber, 2% maleic anhydride, 0.5% antioxidant aging agent 4020, 0.5% antioxidant aging agent diphenylamine, 1% ultraviolet absorber UV-P, 1% light stabilizer Tinuvin 292; the preparation method is as follows: Add the devulcanized rubber to the epoxy soybean oil and palm oil, stir and mix thoroughly, and keep the mixture at 135° C. for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-E; The mixture A1-E was sheared for 30 min at 4000 rpm using a high-speed shearing machine at 160° C. to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-E; A cross-linking agent was added to the mixture A2-E, and the mixture A2-E was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-E; Adding a light aging inhibitor and an antioxidant to the mixture A3-E, stirring the mixture A3-E at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-E; The mixture A4-E was placed in a thermostatic box at 135° C. for 30 min to obtain an environmentally friendly SBS modified asphalt regeneration agent AE.

[0046] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AE regenerated SBS modified asphalt.

[0047] Embodiment 6: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The composition and mass percentage of each raw material of the regeneration agent are as follows: 50% castor seed oil, 45% SBR desulfurized rubber, 2% maleic anhydride, 0.5% antioxidant aging agent antioxidant 4020, 0.5% antioxidant aging agent antioxidant 4010NA, 1% ultraviolet absorber UV-P, 1% light stabilizer Tinuvin 292; the preparation method is as follows: Add the desulfurized rubber into castor seed oil, stir and mix thoroughly, and keep the mixture at 135° C. for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-F; The mixture A1-F was sheared for 30 min at 4000 rpm at 160° C. using a high-speed shearing machine to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-F; A cross-linking agent was added to the mixture A2-F, and the mixture A2-F was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-F; Adding a light aging inhibitor and an antioxidant to the mixture A3-F, stirring the mixture A3-F at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-F; The mixture A4-F was placed in a thermostatic box at 135° C. for 30 minutes to obtain an environmentally friendly SBS modified asphalt regeneration agent AF.

[0048] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AF regenerated SBS modified asphalt.

[0049] Embodiment 7: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The composition and mass percentage of each raw material of the regeneration agent are as follows: 25% palm oil, 25% castor seed oil, 45% SBR desulfurized rubber, 2% maleic anhydride, 1% antioxidant 4020, 1% UV absorber UV-328, 1% light stabilizer Tinuvin 622; the preparation method is as follows: Add the desulfurized rubber to the palm oil and castor seed oil, stir and mix thoroughly, and keep the mixture at 135° C. for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-G; The mixture A1-G was sheared for 30 min at 4000 rpm using a high-speed shearing machine at 160° C. to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-G; A cross-linking agent was added to the mixture A2-G, and the mixture A2-G was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-G; Adding a light aging inhibitor and an antioxidant to the mixture A3-G, stirring the mixture A3-G at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-G; The mixture A4-G was placed in a thermostatic box at 135° C. for 30 min to obtain an environmentally friendly SBS modified asphalt regeneration agent AG.

[0050] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AG regenerated SBS modified asphalt.

[0051] Embodiment 8: A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent comprises the following steps: The raw material composition and mass percentage of the regeneration agent are as follows: 60% palm oil, 37% SBR desulfurized rubber, 1.5% maleic anhydride, 0.5% antioxidant aging agent 4020, 0.5% ultraviolet absorber UV-328, 0.5% light stabilizer Tinuvin622; the preparation method is as follows: Add the desulfurized rubber to the palm oil, stir and mix thoroughly, and keep the mixture at 135°C for 30 minutes to achieve wetting of the solid particles in the liquid phase, thereby obtaining a mixture A1-H; The mixture A1-H was sheared for 30 min at 4000 rpm at 160° C. using a high-speed shearing machine to achieve deagglomeration and dispersion of solid particle agglomerates, thereby obtaining a mixture A2-H; A cross-linking agent was added to the mixture A2-H, and the mixture A2-H was sheared at 160° C. and 4000 rpm for 30 min using a high-speed shearing machine to stabilize the depolymerized slurry and prevent reagglomeration, thereby obtaining a mixture A3-H; Adding an anti-light aging agent and an anti-oxidation aging agent to the mixture A3-H, stirring the mixture A3-H at 160° C. and 1500 rpm for 60 min using a stirrer to achieve anti-aging and stability of the slurry, thereby obtaining a mixture A4-H; The mixture A4-H was placed in a thermostatic box at 135° C. for 30 min to obtain an environmentally friendly SBS modified asphalt regeneration agent AH.

[0052] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. The three-step environmentally friendly SBS modified asphalt regeneration agent prepared above was added to the aged SBS modified asphalt at a mass ratio of 8% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain AH regenerated SBS modified asphalt.

[0053] Comparative Example 1: The difference between Comparative Example 1 and Example 1 is that the regeneration agent A used in Comparative Example 1 is a common regeneration agent sold on the market.

[0054] By comparing the regeneration agent A sold on the market with the three-step environmentally friendly SBS modified asphalt regeneration agent in the present invention, the advantages of the three-step environmentally friendly SBS modified asphalt regeneration agent developed by the present invention are verified. The market price of the commercially available regeneration agent A in comparative example 1 is 15,800 yuan / ton, and the cost of the three-step environmentally friendly SBS modified asphalt regeneration agent of the present invention is about 7,500 yuan / ton.

[0055] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. Commercially available regeneration agent A was added to the aged SBS modified asphalt. Tackifying resin was added to the regeneration agent A. The mass ratio of the regeneration agent A was 7% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain A regenerated SBS modified asphalt.

[0056] Comparative Example 2: Comparative Example 2 is another regeneration agent used in the industry to regenerate SBS-modified aged asphalt. The regeneration principle of this regeneration agent is to introduce chemicals that can react with SBS to achieve the purpose of linking the aged SBS fragments. This regeneration agent has certain environmental hazards. The purpose of comparing with this reaction regeneration agent is to highlight the environmental friendliness of the regeneration agent in the present invention.

[0057] A reaction regeneration agent B is prepared, wherein the regeneration agent B is composed of palm oil and a reaction compound in a mass ratio of 5:1, and the reaction compound is composed of diphenylmethane diisocyanate (MDI) and hexamethylene diisocyanate (HDI) in a mass ratio of 1:3.

[0058] Aged SBS modified asphalt was prepared by a rotary thin film oven aging instrument and a pressure aging instrument. Reaction regeneration agent B was added to the aged SBS modified asphalt at a mass ratio of 5% of the aged SBS modified asphalt. The temperature was maintained at 160°C and stirred at 800 rpm for 30 minutes to obtain B regenerated SBS modified asphalt.

[0059] Experimental example: The regenerated asphalt prepared in Examples 1 to 8 and Comparative Examples 1 to 2 was tested for performance to study the regeneration effect of each regeneration agent on aged SBS modified asphalt. The regeneration effect evaluation test was conducted in accordance with the relevant test requirements in the "Test Procedures for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011), and the performance indicators of the regenerated asphalt are shown in Table 1.

[0060] Table 1 Performance indexes of recycled SBS modified asphalt

[0061] The application of the regeneration agent mainly depends on the performance recovery of the regenerated asphalt at the optimal dosage of the regeneration agent. Therefore, the evaluation of the quality of the regeneration agent in the present invention is to see whether the performance of various regenerated asphalts in the embodiments and comparative examples can be restored to the performance indicators close to SBS modified asphalt as much as possible after the use of the regeneration agent. The closer to the performance of SBS modified asphalt, the more stable the regeneration agent is and the better the performance.

[0062] As shown in Table 1, at the optimal dosage of the regeneration agent, the embodiments can restore the performance indicators of the PAV-aged SBS-modified aged asphalt to the level before aging. Obviously, by comparing with the comparative example, it can be found that the regeneration effect of the regeneration agent in the embodiment is more stable. The comparison between Examples 1-8 shows that different conditions and different additives selected within the given condition range in the preparation step of the present invention have good regeneration effects.

[0063] Figure 2 This is a three-step environmentally friendly SBS modified asphalt regeneration agent application effect verification diagram of the present invention, which shows the phase angle curve changes of the regenerated asphalt in the comparative example and the embodiment of the present invention; Figure 2 The phase angle variation curves of the comparative examples and examples of the regenerated asphalt are given. The destruction and regeneration of the internal polymer network of the SBS modified asphalt can be judged from the platform area of ​​the phase angle variation curve. Figure 2 It can be seen from the above that all embodiments of the present invention have excellent regeneration effects on the polymer network; Figure 2 It can also be seen that the phase angle of the comparative example is significantly lower than that of the other embodiments and SBS modified asphalt. In this case, the low-temperature performance of the regenerated asphalt using the regeneration agent in the comparative example will be poor.

[0064] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A three-step method for preparing an environmentally friendly SBS modified asphalt regeneration agent, characterized in that: The following steps are involved: S1. Raw material preparation: prepare the following raw materials by mass: 50-70 parts of bio-oil, 40-60 parts of devulcanized rubber, 3-9 parts of cross-linking agent, 1-2 parts of antioxidant, and 1-2 parts of anti-light aging agent; The bio-oil is one or a combination of soybean oil, rapeseed oil, palm oil, kitchen waste oil and their derivative oils, and the mixture can be in any proportion; The raw material of the devulcanized rubber is derived from one or a combination of natural rubber, styrene-butadiene rubber, butadiene rubber, chloroprene rubber, and nitrile rubber, and the mixture can be in any proportion; The crosslinking agent is one of maleic anhydride, maleic anhydride grafted SEBS, and maleic anhydride grafted tackifying resin; The antioxidant is one of N-phenyl-α-naphthylamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, diphenylamine, and p-aminodiphenylamine; The anti-photoaging agent is one or a combination of ultraviolet absorbers and light stabilizers, and the mixture can be in any proportion; The ultraviolet absorber is one of 2-hydroxy-4-methoxybenzophenone, 2,6-dimethylbenzotriazole, and 2-(2'-hydroxy-5'-methylphenyl)benzotriazole; The light stabilizer is one of bis(2,2,6,6-tetramethyl-4-piperidinyl) adipate, poly(4-methyl-2,6-dipentyl) piperidinyl succinate, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate; S2. The preparation of SBS modified asphalt regeneration agent includes the following steps: S2-1, adding desulfurized rubber to bio-oil, stirring and mixing, and keeping the mixture at 135° C. for 30 min to 60 min to achieve wetting of solid particles in the liquid phase, to obtain a mixture A1; S2-2, using a high-speed shearing machine at 160° C. and a rotation speed of 4000 rpm to shear the mixture A1 for 30 min to 60 min to achieve deagglomeration and dispersion of solid particle agglomerates to obtain a mixture A2; S2-3, adding a crosslinking agent to the mixture A2, and shearing the mixture A1 with a high-speed shearing machine at 160° C. and a rotation speed of 4000 rpm for 30 min to 60 min to stabilize the slurry after depolymerization and prevent reagglomeration, thereby obtaining a mixture A3; S2-4, adding a light aging inhibitor and an antioxidant to the mixture A3, stirring the mixture A3 at 160° C. and 1500 rpm for 60 min to 90 min using a stirrer to achieve anti-aging and stabilization of the slurry, to obtain a mixture A4; S2-5. Place the mixture A4 in a constant temperature box at 135°C for 30 min to 60 min to obtain a three-step environmentally friendly SBS modified asphalt regeneration agent. Add the prepared three-step environmentally friendly SBS modified asphalt regeneration agent to the aged SBS modified asphalt in an amount of 4% to 20% by mass. After stirring evenly, the prepared regenerated SBS modified asphalt has the following performance indicators: needle penetration 0.1mm is 44.2-46.8; elongation at 5°C is 28.4cm-31.1cm; softening point is 60.4°C-62.7°C; viscosity at 135°C is 2186mPa•s-2280 mPa•s.

2. The method for preparing a three-step environmentally friendly SBS modified asphalt regeneration agent according to claim 1, characterized in that: The raw material preparation described in S1 is to prepare the following raw materials in parts by mass: 60 parts of bio-oil, 50 parts of devulcanized rubber, 6 parts of cross-linking agent, 1.5 parts of antioxidant and 1.5 parts of anti-light aging agent.

3. The method for preparing a three-step environmentally friendly SBS modified asphalt regeneration agent according to claim 1, characterized in that: The desulfurization process of the desulfurized rubber described in S1 is physical desulfurization or chemical desulfurization, and the degree is above 50%.

4. A three-step environmentally friendly SBS modified asphalt regeneration agent, characterized by: The three-step environmentally friendly SBS modified asphalt regeneration agent prepared by the method for preparing any one of claims 1 to 3 can realize the dual regeneration of asphalt matrix and SBS modifier in the aged SBS modified asphalt system. The prepared three-step environmentally friendly SBS modified asphalt regeneration agent is added to the aged SBS modified asphalt in an amount of 4% to 20% by mass, and after uniform stirring, the prepared three-step environmentally friendly SBS modified asphalt regeneration agent has the following performance indicators: needle penetration 0.1mm is 44.2-46.8; elongation at 5°C is 28.4cm-31.1cm; softening point is 60.4°C-62.7°C; viscosity at 135°C is 2186 mPa•s-2280 mPa•s.

5. The use of a three-step environmentally friendly SBS modified asphalt regeneration agent as described in claim 4, characterized in that: The prepared three-step environmentally friendly SBS modified asphalt regeneration agent is added to the aged SBS modified asphalt in an amount of 4% to 20% by mass. The aged SBS modified asphalt and the three-step environmentally friendly SBS modified asphalt regeneration agent are stirred evenly in a mixer under heating conditions of 145°C to 165°C. The stirring speed is 800rpm to 1500rpm and the stirring time is 30min to 60min to prepare regenerated SBS modified asphalt for use in road engineering.

6. The use of a three-step environmentally friendly SBS modified asphalt regeneration agent according to claim 5, characterized in that: The aged SBS modified asphalt is one of film aged asphalt, rotary film aged asphalt, ultraviolet aged asphalt, pressure aged asphalt, waste extraction aged asphalt and a mixture of multiple thereof in any proportion.

7. The use of a three-step environmentally friendly SBS modified asphalt regeneration agent according to claim 5, characterized in that: The heating condition is 155°C.

8. The use of a three-step environmentally friendly SBS modified asphalt regeneration agent according to claim 5, characterized in that: The stirring speed of the stirrer is 1000 rpm, and the stirring time is 45 min.

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