A cross-linked polymer type aging SBS modified asphalt green recycling agent based on multiple waste components, and a preparation method and application thereof

Abstract

The application discloses a kind of green recycling agent based on multiple waste components of crosslinking polymer type aging SBS modified asphalt and its preparation method and application, belong to waste-based recycling agent technical field, preparation method is to mix uniformly and swell with waste vegetable oil, desulfurization reclaimed rubber powder, waste-based reinforcing agent, obtain swelling gel;Dynamic crosslinking agent and dynamic crosslinking active agent are added to swelling gel, and waste-based pre-crosslinking polymer is prepared by vulcanization reaction;After development in oven, it is obtained;Compared with traditional petroleum-based recycling agent, the green recycling agent based on multiple waste components of crosslinking polymer type aging SBS modified asphalt of the application uses waste as raw material, realizes chemical bonding to aging SBS modified asphalt by constructing rigid-flexible three-dimensional chemical crosslinking network, repairs aging degradation, improves the high-low temperature performance, elastic recovery and anti-aging ability of recycled asphalt, realizes high-value utilization of waste asphalt mixture.

Description

Technical Field

[0001] This invention belongs to the field of waste-based recycler technology, specifically relating to a cross-linked polymer-based green recycler for aged SBS modified asphalt based on multiple waste components, its preparation method, and its application. Background Technology

[0002] Asphalt, with its excellent road performance and relatively economical cost, has become the most widely used pavement material in the world today. However, during long-term service, as an organic polymer material, asphalt undergoes aging under the coupled effects of multiple environmental factors such as temperature, light, oxygen, and precipitation. The lightweight components in asphalt volatilize, and the macromolecular chains oxidize, break down, or polymerize. Aging asphalt exhibits hardening and brittleness, reduced penetration, and increased softening point and viscosity, leading to pavement defects such as cracks, loosening, and potholes, severely shortening the service life of roads. To improve the service performance and extend the durability of asphalt pavements, researchers have proposed a technical route of modifying base asphalt using polymers. Among these, styrene-butadiene-styrene block copolymer (SBS) has become the most widely used and effective asphalt modifier because it can simultaneously improve the high-temperature rutting resistance, low-temperature crack resistance, and elastic recovery of asphalt. The large-scale application of SBS-modified asphalt has significantly increased the requirements of modern transportation for pavement quality.

[0003] However, SBS modified asphalt also faces the problem of aging. With increasing service life, under the long-term effects of heat, oxygen, and ultraviolet radiation, the SBS polymer in SBS modified asphalt degrades, and the unsaturated double bonds in its butadiene segments are destroyed, leading to the disintegration of the SBS network structure; simultaneously, the asphalt matrix also undergoes oxidative aging. This complex aging process causes a sharp decline in the performance of SBS modified asphalt, even more complex than the aging process of ordinary asphalt. When these aged SBS modified asphalt mixtures are repaired and milled off, their performance is far from meeting the basic requirements for road service. If they cannot be effectively recycled, it will not only cause enormous waste of resources but also bring severe environmental pressure.

[0004] Currently, the industrial method for regenerating aged SBS modified asphalt commonly involves adding regenerators. The principle is to replenish the missing lightweight components in the aged asphalt and adjust its colloidal structure to restore its rheological properties. However, most commercially available asphalt regenerators are primarily composed of petroleum-based distillate oils (such as aromatic hydrocarbon oils and naphthenic oils). These petroleum-based regenerators are not only highly susceptible to cost fluctuations due to crude oil prices, but their production and use are also heavily reliant on non-renewable petrochemical resources, which contradicts the principles of green, low-carbon, and sustainable development. Furthermore, some petroleum-based regenerators contain large amounts of volatile organic compounds (VOCs), which can cause environmental pollution during construction and pose a potential threat to the health of construction workers. More importantly, traditional regenerators typically only act as physical modifiers and diluents, failing to effectively repair the degraded structure of aged SBS and thus having limited regeneration effects on SBS modified asphalt, unable to truly restore its properties to their unaged state.

[0005] Therefore, developing a green recycler that is independent of petroleum resources, environmentally friendly, cost-controllable, and can effectively repair the structure of aged SBS has become an urgent technical challenge in the field of road engineering. Based on this, this invention proposes a green recycler for aged SBS modified asphalt based on a cross-linked polymer with multiple waste components, along with its preparation method and application. This invention uses waste desulfurized recycled rubber powder, waste vegetable oil, waste-based reinforcing agents, and waste-based cross-linking activators as raw materials. By constructing a novel cross-linked polymer network, it aims to achieve dual repair of the chemical structure and physical properties of aged SBS modified asphalt, while simultaneously realizing the circular economy goal of "treating waste with waste." Summary of the Invention

[0006] Technical problems solved: In view of the problems of excessive reliance on petroleum-based resources, difficulty in repairing the degradation structure of aged SBS, difficulty in the synergistic utilization of multiple wastes, and high environmental emissions during construction, the present invention provides a green recycling agent for aged SBS modified asphalt based on cross-linked polymers with multiple waste components, its preparation method and application.

[0007] Purpose of the invention: This application aims to achieve dual repair of the chemical structure and physical properties of aged SBS modified asphalt by constructing a waste-based crosslinking network through chemical crosslinking, thereby improving the comprehensive road performance of recycled asphalt, increasing the high-value utilization rate of RAP materials, realizing the high-value utilization of waste, reducing carbon emissions during construction, and contributing to the green, low-carbon, and circular development of road infrastructure construction.

[0008] This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: Proportioning by weight: Add 100 parts waste vegetable oil, 40-120 parts desulfurized reclaimed rubber powder, and 30-50 parts waste-based reinforcing agent sequentially to a clean three-necked flask at room temperature and mix thoroughly. At a constant temperature of 140-160℃, stir at a speed of 400 r / min to ensure uniform mixing. Simultaneously, allow the desulfurized reclaimed rubber powder to swell in the waste vegetable oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 5-8 parts of dynamic crosslinking agent, and 2-3 parts of dynamic crosslinking activator according to the mass ratio. After mixing evenly, purge with inert gas for 15-20 minutes, and then react at a constant temperature of 150-180℃ and a stirring rate of 200-400r / min for 45-90 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and allow it to develop at 140-160℃ for 30-60 minutes to obtain a crosslinked polymer-based green regenerator for aged SBS modified asphalt based on multiple waste components.

[0009] As a preferred technical solution of the present invention: the waste vegetable oil is one or more of the following: waste edible oil, waste soybean oil, waste rapeseed oil, waste castor oil, waste cottonseed oil, waste peanut oil, waste corn oil, waste olive oil, waste sunflower seed oil, waste high-oleic rapeseed oil, waste high-oleic peanut oil, waste high-oleic olive oil, waste high-oleic sunflower seed oil, waste high-oleic avocado oil, waste high-oleic camellia oil, waste high-oleic soybean oil, and derivatives of the above-mentioned vegetable oils.

[0010] As a preferred embodiment of the present invention, the waste-based reinforcing agent is one or more of the following: carbon black, rice husk ash, wood ash, wood flour, fly ash, silica fume, waste polyurethane foam, waste thermosetting plastics, and derivatives of the above-mentioned waste-based reinforcing agents.

[0011] As a preferred embodiment of the present invention, the dynamic crosslinking agent is one or more of the following: sulfur, thioctic acid, morpholine disulfide, tetramethylthiuram disulfide, selenium dimethyl dithiocarbamate, 4,4'-diaminodiphenyl disulfide, bis(3-carboxypropyl) disulfide, N,N'-m-phenylenebismaleimide, 1,2-bis(maleimide)ethane, 1,8-bismaleimide diphenylmethane, and derivatives of the above-mentioned dynamic crosslinking agents.

[0012] As a preferred embodiment of the present invention, the dynamic crosslinking activator is one or more of zinc oxide, magnesium oxide, lead oxide, calcium oxide, calcium hydroxide, stearic acid, zinc stearate, diethanolamine, and derivatives of the above-mentioned dynamic crosslinking promoters.

[0013] A cross-linked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components, prepared by any of the above preparation methods.

[0014] This application also discloses the application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt.

[0015] As a preferred technical solution of the present invention: under the condition of 130-150℃, 5-10 parts of cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components are added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio to obtain a mixture. The mixture is stirred at a stirring rate of 200-600r / min for 30-60 minutes using an electric stirrer to obtain SBS modified asphalt regenerated by cross-linked polymer based on multiple waste components. After standing at room temperature for 1 day, the performance of aged SBS modified asphalt regenerated by cross-linked polymer based on multiple waste components is tested.

[0016] Explanation of the principle: First, in the regenerator preparation stage, waste vegetable oil, desulfurized regenerated rubber powder, and waste-based reinforcing agent undergo chemical bonding under the action of a vulcanizing crosslinking agent. Unlike traditional physical blending, the waste vegetable oil in this invention does not exist as an inert plasticizer, but rather participates in the construction of the crosslinking network as an active reactive component. Under heating conditions, the crosslinking agent reacts with the unsaturated double bonds in the waste vegetable oil molecular chain, the residual rubber hydrocarbon active sites in the desulfurized regenerated rubber powder, and the active functional groups on the surface of the waste-based reinforcing agent to form a sulfur bridge structure, connecting the components through chemical bonds into a unified three-dimensional crosslinking network. In this crosslinking network, the components play a synergistic role: waste... Vegetable oils, with their long-chain flexible molecular structure, provide relaxation properties to the network, forming flexible microdomains and giving the regenerator good low-temperature ductility. Desulfurized regenerated rubber powder, with its styrene and polybutadiene segments, provides rigid microdomains and dense cross-linking sites, ensuring that the network has sufficient structural strength and elastic recovery ability. Waste-based reinforcing agents are uniformly dispersed in the network, serving both as physical cross-linking points to enhance network stability and utilizing their micron / nano-scale particle characteristics to play a reinforcing role. Through pre-swelling treatment during the preparation process, the above-mentioned flexible and rigid microdomains are ensured to be uniformly distributed, forming a polymer network with a uniform structure after vulcanization, thereby achieving a microstructure design that combines rigidity and flexibility. When the regenerator described in this invention is applied to aged SBS modified asphalt, its mechanism of action is further deepened. During high-temperature mixing, some sulfur bridges undergo reversible breakage, exposing active sites. These sites can react with active functional groups in the aged asphalt (such as carbonyl groups, sulfoxide groups, and unsaturated end groups remaining after the degradation of aged SBS), chemically bonding the effective components in the aged asphalt to the crosslinking network. Since the mixing temperature is lower than the vulcanization crosslinking temperature, the breakage and recombination rate of sulfur bridges is relatively slow. Therefore, the main structure of the crosslinking network is preserved, and only a small number of sulfur bridges bond with asphalt molecules, effectively avoiding the phenomenon of excessive gelation of asphalt. In the recycled asphalt, the aged asphalt components are encapsulated within a cross-linked polymer network, which provides triple protection: First, physical buffering—the network structure dissipates stress concentration caused by external loads, reducing the asphalt's sensitivity to temperature and load, and improving the pavement's resistance to rutting and cracking; Second, chemical repair—the flexible segments provided by waste vegetable oil in the network replenish the lightweight components missing in the aged asphalt, while the active sites provided by desulfurized recycled rubber powder participate in repairing the degradation structure of aged SBS, restoring the recycled asphalt's elasticity; Third, barrier protection—the dense cross-linked network effectively blocks the diffusion and penetration of oxygen into the asphalt, slowing down the rate of thermo-oxidative aging of the asphalt during service, thereby significantly extending the durability and service life of the recycled pavement. In summary, this invention achieves dual repair of the chemical structure and physical properties of aged SBS modified asphalt by constructing a multi-waste-based crosslinked polymer network. At the same time, it reduces the carbon footprint of the recycling agent through a "waste-to-waste" approach, providing a new path for the green, low-carbon, and circular development of road infrastructure.

[0017] Compared with the prior art, this application has the following advantages: 1. Existing regenerants mostly use petroleum-based distillate oils as their main component, and their production is highly dependent on non-renewable petrochemical resources and is greatly affected by fluctuations in crude oil prices. This invention uses waste vegetable oil, desulfurized regenerated rubber powder, and industrial / agricultural waste residues (such as rice husk ash, fly ash, and zinc oxide derived from waste batteries) as raw materials to construct a multi-waste component regenerant system, in which waste raw materials account for more than 90%. On the one hand, it realizes the synergistic high-value utilization of multiple wastes, transforming "low-value waste" into "high-performance regenerants," truly practicing the circular economy concept of "treating waste with waste." On the other hand, it completely or partially eliminates dependence on petroleum-based resources, significantly reducing the carbon footprint of the regenerant, and lowering production costs by approximately 30-40% compared to petroleum-based regenerants. 2. Existing regenerators mainly soften asphalt by adding lightweight components to aged asphalt through physical blending, which is a physical filling type of regeneration. This type of regeneration cannot repair the degradation structure of aged SBS polymers, resulting in poor elastic recovery and limited improvement in high and low temperature performance of the regenerated modified asphalt. This invention constructs a multi-waste-based cross-linked polymer network, enabling chemical bonding between the regenerator and aged asphalt. The long-chain flexible molecules of waste vegetable oil and the rigid segments in desulfurized regenerated rubber powder form a sulfur bridge network under the action of the cross-linking agent, and react with the active functional groups in the aged asphalt, repairing the degradation network of aged SBS at the chemical structure level. Tests show that this regenerator can reduce the carbonyl index of aged asphalt by more than 40%, and the fatigue life of the regenerated asphalt is increased by more than 50% compared with traditional petroleum-based regenerators, achieving a fundamental recovery of the performance of the regenerated asphalt. 3. Existing recycling agents have a single component, making it difficult to simultaneously meet the dual requirements of asphalt for high-temperature stability and low-temperature crack resistance. This invention chemically links a flexible component (waste vegetable oil) with a rigid component (desulfurized recycled rubber powder) through a cross-linking reaction, forming a micro-phase structure that combines rigidity and flexibility. The flexible micro-regions introduced by the waste vegetable oil endow the recycled asphalt with excellent low-temperature ductility and stress relaxation ability, reducing the low-temperature critical cracking temperature of the recycled asphalt by about 4-6℃. The rigid micro-regions contributed by the desulfurized recycled rubber powder ensure that the recycled asphalt has sufficient high-temperature rutting resistance and elastic recovery performance, and the high-temperature PG grading can be improved by 1-2 grades. The introduction of waste-based reinforcing agents (such as rice husk ash) further enhances the mechanical stability of the network structure, achieving a synergistic improvement in the comprehensive road performance of recycled asphalt. 4. Existing recycling agents are prone to secondary aging during service, making it difficult to guarantee the long-term durability of recycled pavements. The cross-linked polymer network formed by the recycling agent described in this invention in aged SBS modified asphalt not only provides structural reinforcement but also constitutes a physical barrier. This network effectively blocks the diffusion and penetration of oxygen into the asphalt, slowing down the rate of thermo-oxidative aging and improving the anti-aging performance of recycled asphalt by approximately 35%. At the same time, the network structure can buffer stress concentration caused by temperature changes and loads, reducing the asphalt's sensitivity to temperature and loads, extending the fatigue life of recycled asphalt by more than 60%, and increasing the elastic recovery rate to over 85%. This dual protection mechanism of "external barrier and internal buffer" significantly improves the anti-aging and anti-fatigue performance of recycled asphalt, thereby effectively extending the service life of recycled pavements and reducing the total life-cycle maintenance cost by approximately 25-30%. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to embodiments and comparative examples. It should be noted that the specific embodiments described herein are only for explaining the present invention and do not limit the scope and application of the present invention.

[0019] The performance testing method for cross-linked polymer-regenerated aged SBS modified asphalt based on multiple waste components refers to the "Technical Specification for Construction of Highway Asphalt Pavement" (Industry Standard of the People's Republic of China, JTG F40-2004).

[0020] Example 1: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts waste cooking oil, 40 parts desulfurized regenerated rubber powder, and 30 parts carbon black one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 140℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized regenerated rubber powder to fully swell in the waste cooking oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 5 parts of sulfur, and 2 parts of zinc oxide according to the mass ratio. After mixing evenly, purge with inert nitrogen gas for 15 minutes and react at a constant temperature of 150℃ and a stirring rate of 200r / min for 45 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 140°C for 30 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0021] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 130℃, 5 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 30 minutes at a stirring rate of 200 r / min using an electric stirrer to obtain recycled SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt based on multiple waste components was tested.

[0022] Comparative Example 1: Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 5 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. The mixture was left to stand at room temperature for 1 day, and the performance of SBS modified asphalt was tested.

[0023] Table 1. Basic parameters of the modified asphalt prepared in Example 1 and Comparative Example 1 .

[0024] As shown in Table 1, the regenerator of this invention can effectively rebuild the three-dimensional cross-linked network structure in aged SBS modified asphalt systems, enabling the recycled asphalt to fully recover to a near-unaged state in terms of conventional road performance indicators. This regeneration system repairs the colloidal structure lost during the aging process through chemical bonding, thereby effectively improving the recovery ability of the basic physical properties of the recycled asphalt.

[0025] Example 2: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts waste soybean oil, 50 parts desulfurized regenerated rubber powder, and 35 parts rice husk ash one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 140℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized regenerated rubber powder to fully swell in the waste soybean oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 6 parts of thioctic acid and 2.5 parts of magnesium oxide according to the mass ratio, then purge with inert nitrogen gas for 20 minutes, and react at a constant temperature of 160℃ and a stirring rate of 250 r / min for 50 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 150°C for 40 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0026] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 140℃, 6 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 40 minutes at a stirring rate of 250 r / min using an electric stirrer to obtain recycled SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt based on multiple waste components was tested.

[0027] Comparative Example 2, Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. The mixture was left to stand at room temperature for 1 day, and the performance of SBS modified asphalt was tested.

[0028] Table 2. Basic parameters of the modified asphalt prepared in Example 2 and Comparative Example 2. .

[0029] As shown in Table 2, the regenerator of this invention can construct a stable rigid skeleton structure in the aged SBS modified asphalt system, enabling the recycled asphalt to maintain good deformation resistance and rutting resistance under high temperature conditions. This recycled system exhibits structural stability under high-temperature shear and is not prone to flow deformation, thus effectively improving the high-temperature stability of asphalt materials.

[0030] Example 3: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts waste rapeseed oil, 60 parts desulfurized regenerated rubber powder, and 45 parts wood ash one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 150℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized regenerated rubber powder to fully swell in the waste rapeseed oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 7 parts of N,N'-m-phenylenebismaleimide and 3 parts of lead oxide according to the mass ratio. After mixing evenly, purge with inert nitrogen gas for 20 minutes and react at a constant temperature of 170℃ and a stirring rate of 350r / min for 70 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 150°C for 60 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0031] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 145℃, 10 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 50 minutes at a stirring rate of 300 r / min using an electric stirrer to obtain recycled SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt based on multiple waste components was tested.

[0032] Comparative Example 3: Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. The mixture was left to stand at room temperature for 1 day, and the performance of SBS modified asphalt was tested.

[0033] Table 3. Basic parameters of the modified asphalt prepared in Example 3 and Comparative Example 3 .

[0034] As shown in Table 3, the regenerator of this invention can introduce flexible relaxation micro-regions into the aged SBS modified asphalt system, enabling the recycled asphalt to maintain good stress dispersion and crack resistance under low-temperature conditions. This recycled system can effectively dissipate internal stress during rapid temperature drops, making it less prone to brittle fracture, thereby effectively improving the low-temperature crack resistance of asphalt materials.

[0035] Example 4: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts of waste castor oil, 70 parts of desulfurized reclaimed rubber powder, and 45 parts of wood flour one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 155℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized reclaimed rubber powder to fully swell in the waste castor oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 8 parts of morpholine disulfide and 3 parts of calcium oxide according to the mass ratio, then purge with inert nitrogen gas for 15 minutes, and react at a constant temperature of 150℃ and a stirring rate of 250r / min for 80 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 160°C for 60 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0036] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 150°C, 8 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 55 minutes at a stirring rate of 450 r / min using an electric stirrer to obtain recycled SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt based on multiple waste components was tested.

[0037] Comparative Example 4: Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. The mixture was left to stand at room temperature for 1 day, and the performance of SBS modified asphalt was tested.

[0038] Table 4. Basic parameters of the modified asphalt prepared in Example 4 and Comparative Example 4 .

[0039] As shown in Table 4, the regenerator of this invention can repair the degraded elastic network structure in aged SBS modified asphalt systems, enabling the recycled asphalt to maintain good elastic recovery and fatigue resistance under repeated loading. This regenerated system can effectively store and release elastic strain energy during loading-unloading cycles, thereby effectively improving the elastic response of asphalt materials.

[0040] Example 5: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts waste cottonseed oil, 60 parts desulfurized regenerated rubber powder, and 45 parts fly ash one by one into a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 155℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized regenerated rubber powder to fully swell in the waste cottonseed oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 8 parts of tetramethylthiuram disulfide and 3 parts of stearic acid according to the mass ratio, then seal and purge with inert gas for 20 minutes, and react at a constant temperature of 175℃ and a stirring rate of 350r / min for 85 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 155°C for 55 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0041] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 145℃, 9 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 55 minutes at a stirring rate of 350 r / min using an electric stirrer to obtain the cross-linked polymer-based aged SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of the cross-linked polymer-based aged SBS modified asphalt based on multiple waste components was tested.

[0042] Comparative Example 5: Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. The mixture was left to stand at room temperature for 1 day, and the performance of SBS modified asphalt was tested.

[0043] Table 5. Basic parameters of the modified asphalt prepared in Example 5 and Comparative Example 5 .

[0044] As shown in Table 5, the regenerator of this invention can achieve uniform distribution and synergistic cooperation of rigid and flexible components in aged SBS modified asphalt systems, enabling the recycled asphalt to maintain good viscoelastic properties under different temperature ranges and loading frequencies. This recycled system exhibits stable mechanical behavior over a wide temperature range, thereby effectively improving the service adaptability of asphalt materials.

[0045] Example 6: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts waste cottonseed oil, 110 parts desulfurized regenerated rubber powder, and 35 parts silica fume one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 140℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized regenerated rubber powder to fully swell in the waste cottonseed oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 8 parts of selenium dimethyl dithiocarbamate and 2 parts of zinc stearate according to the mass ratio, then seal and purge with inert gas for 15 minutes, and react at a constant temperature of 170℃ and a stirring rate of 300r / min for 60 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 150°C for 55 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0046] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt with multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 135℃, 8 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt with multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred for 50 minutes at a stirring rate of 450 r / min using an electric stirrer to obtain recycled SBS modified asphalt with multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt with multiple waste components was tested.

[0047] Comparative Example 6, Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. After standing at room temperature for 1 day, the performance of SBS modified asphalt was tested.

[0048] Table 6. Basic parameters of the modified asphalt prepared in Example 6 and Comparative Example 6 .

[0049] As shown in Table 6, the regenerator of this invention can form a dense physical barrier in the aged SBS modified asphalt system, enabling the recycled asphalt to maintain good performance retention during thermo-oxidative aging. This regeneration system can effectively delay the diffusion and penetration of oxygen into the asphalt interior, thereby effectively improving the asphalt material's resistance to secondary aging.

[0050] Example 7: This invention provides a method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, comprising the following steps: Step 1: According to the mass ratio, add 100 parts of waste high-oleic soybean oil, 60 parts of desulfurized reclaimed rubber powder, and 40 parts of waste polyurethane foam one by one to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 155℃, stir at a speed of 400r / min to mix the three evenly and allow the desulfurized reclaimed rubber powder to fully swell in the waste high-oleic soybean oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 7 parts of N,N'-m-phenylenebismaleimide and 3 parts of diethanolamine according to the mass ratio, then seal and purge with inert gas for 20 minutes, and react at a constant temperature of 180℃ and a stirring rate of 400r / min for 70 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and develop it at 140°C for 40 minutes to obtain a crosslinked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components.

[0051] The application of a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components in the recycling of aged SBS modified asphalt: Under conditions of 140℃, 7 parts of the cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components were added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio. The mixture was stirred at a stirring rate of 400 r / min for 55 minutes using an electric stirrer to obtain recycled SBS modified asphalt based on multiple waste components. After standing at room temperature for 1 day, the performance of recycled SBS modified asphalt based on multiple waste components was tested.

[0052] Comparative Example 7, Preparation method of unaged SBS modified asphalt: The base asphalt was heated to 180℃, and 3 parts of SBS modifier were added to 100 parts of base asphalt according to the mass ratio. The mixture was sheared for 90 minutes at a shear rate of 5000r / min using a high-speed shearing machine to obtain SBS modified asphalt. After standing at room temperature for 1 day, the performance of SBS modified asphalt was tested.

[0053] Table 7. Basic parameters of the modified asphalt prepared in Example 7 and Comparative Example 7 .

[0054] As shown in Table 7, the regenerator of this invention can achieve synergistic optimization of multiple properties in aged SBS modified asphalt systems, enabling the recycled asphalt to exhibit balanced and excellent comprehensive road performance in terms of high and low temperature performance, elastic recovery, and anti-aging properties. This recycling system fully leverages the synergistic effects of various components such as waste vegetable oil, desulfurized recycled rubber powder, and waste-based reinforcing agents, thereby effectively improving the green recycling efficiency of aged SBS modified asphalt.

[0055] The performance results of Examples 1-7 demonstrate that the cross-linked polymer-based green regenerator for aged SBS modified asphalt proposed in this invention, based on multiple waste components, can fully restore the various road performance characteristics of severely deteriorated SBS modified asphalt after aging. This regeneration system utilizes waste vegetable oil to provide flexible segments and reactive sites, desulfurized regenerated rubber powder to contribute rigid micro-regions and residual rubber hydrocarbons, waste-based reinforcing agents to enhance network stability, and waste-based cross-linking activators to activate cross-linking reaction efficiency. These four types of waste components form a unified three-dimensional network through chemical bonding under the action of the vulcanizing cross-linking agent. When this network is mixed with aged asphalt, some cross-linking bonds undergo dynamic breakage and recombination, chemically bonding the effective components of the aged asphalt into the network interior, achieving a leap from physical filling to chemical repair. In the regenerated asphalt, the flexible micro-regions introduced by the waste vegetable oil endow it with good low-temperature stress relaxation capabilities, while the rigid micro-regions contributed by the desulfurized regenerated rubber powder ensure its high-temperature deformation resistance. The uniform dispersion of the reinforcing agent further enhances the mechanical stability of the network. This flexible yet robust microstructure design enables recycled asphalt to exhibit a balanced performance response across a wide temperature range, avoiding the limitations of traditional recycling agents that sometimes sacrifice certain aspects for others. Simultaneously, the cross-linked network's physical barrier to oxygen diffusion significantly slows down the secondary aging process of the recycled asphalt, allowing it to maintain good performance retention during long-term service. Furthermore, this invention replaces petroleum-based raw materials with waste resources, achieving efficient recycling of aged SBS modified asphalt while significantly reducing material costs and carbon footprint, truly achieving a green closed loop of "waste-to-waste" recycling. In summary, the recycling agent described in this invention not only restores the basic properties of aged SBS modified asphalt but also achieves synergistic improvements in high-temperature stability, low-temperature flexibility, anti-aging durability, and environmental sustainability, providing a feasible technical solution for the high-value recycling of waste asphalt mixtures.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a cross-linked polymer-based green recycling agent for aged SBS modified asphalt based on multiple waste components, characterized in that, Includes the following steps: Step 1: According to the mass ratio, add 100 parts waste vegetable oil, 40-120 parts desulfurized reclaimed rubber powder, and 30-50 parts waste-based reinforcing agent to a clean three-necked flask at room temperature and mix evenly. At a constant temperature of 140-160℃, stir at a speed of 400r / min to mix the three evenly, while allowing the desulfurized reclaimed rubber powder to swell in the waste vegetable oil to obtain a swollen gel. Step 2: Mix 100 parts of swelling gel, 5-8 parts of dynamic crosslinking agent, and 2-3 parts of dynamic crosslinking activator according to the mass ratio. After mixing evenly, purge with inert gas for 15-20 minutes, and then react at a constant temperature of 150-180℃ and a stirring rate of 200-400r / min for 45-90 minutes to obtain waste-based pre-crosslinked polymer. Step 3: Transfer the waste-based pre-crosslinked polymer to a constant temperature oven and allow it to develop at 140-160℃ for 30-60 minutes to obtain a crosslinked polymer-based green regenerator for aged SBS modified asphalt based on multiple waste components.

2. The preparation method of a cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components according to claim 1, characterized in that: The waste vegetable oils are waste edible oils, waste soybean oil, waste rapeseed oil, waste castor oil, waste cottonseed oil, waste peanut oil, waste corn oil, waste olive oil, waste sunflower seed oil, waste high-oleic rapeseed oil, waste high-oleic peanut oil, waste high-oleic olive oil, waste high-oleic sunflower seed oil, waste high-oleic avocado oil, waste high-oleic camellia oil, waste high-oleic soybean oil, and one or more of the above-mentioned vegetable oil derivatives.

3. The preparation method of a cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components according to claim 1, characterized in that: The waste-based reinforcing agent is one or more of the following: carbon black, rice husk ash, plant ash, wood flour, fly ash, silica fume, waste polyurethane foam, waste thermosetting plastics, and derivatives of the above-mentioned waste-based reinforcing agents.

4. The preparation method of a cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components according to claim 1, characterized in that: The dynamic crosslinking agent is one or more of the following: sulfur, thioctic acid, morpholine disulfide, tetramethylthiuram disulfide, selenium dimethyl dithiocarbamate, 4,4'-diaminodiphenyl disulfide, bis(3-carboxypropyl) disulfide, N,N'-m-phenylenebismaleimide, 1,2-bis(maleimide)ethane, 1,8-bismaleimide diphenylmethane, and derivatives of the above dynamic crosslinking agents.

5. The preparation method of a cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components according to claim 1, characterized in that: The dynamic crosslinking activator is one or more of zinc oxide, magnesium oxide, lead oxide, calcium oxide, calcium hydroxide, stearic acid, zinc stearate, diethanolamine, and derivatives of the above dynamic crosslinking promoters.

6. A cross-linked polymer-based aged SBS modified asphalt green regenerator based on multiple waste components, prepared by the preparation method according to any one of claims 1-5.

7. The application of a cross-linked polymer-based green regenerator for aged SBS modified asphalt, prepared by any one of claims 1-5, in the regenerated aged SBS modified asphalt.

8. The application according to claim 7, characterized in that: Under conditions of 130-150℃, 5-10 parts of cross-linked polymer-based aged SBS modified asphalt green recycling agent based on multiple waste components are added to 100 parts of aged SBS modified asphalt according to the mass fraction ratio to obtain a mixture. The mixture is stirred for 30-60 minutes at a stirring rate of 200-600r / min using an electric mixer to obtain SBS modified asphalt recycled based on cross-linked polymer based on multiple waste components. After standing at room temperature for 1 day, the performance of SBS modified asphalt based on cross-linked polymer regeneration and aging with multiple waste components was tested.