A long-life pavement material under extremely complex conditions and its preparation method

Abstract

This invention discloses a long-life pavement material for extreme and complex conditions and its preparation method. Modified asphalt pavement material is prepared using ultra-deeply decrosslinked rubber as the main raw material (with a content greater than 50%). Through specific processes and formulations, this pavement material retains excellent self-healing properties even under extreme low-temperature conditions (< -10 °C), with a healing efficiency greater than 50%, and a healing efficiency greater than 30% after aging, resulting in a long service life. This invention not only solves the problem of easy cracking in asphalt pavements and significantly improves their service life, but also enables the high-value resource utilization of waste rubber, resulting in significant environmental and economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of road materials technology, and relates to a long-life pavement material under extremely complex conditions and its preparation method. Background Technology

[0002] Asphalt, a widely used road construction material, directly impacts the service life and safety of roads. However, traditional asphalt pavements are prone to cracking and accelerated aging under low-temperature conditions (especially in extreme and complex climates), leading to shorter lifespans and increased road maintenance costs. In recent years, self-healing pavement materials have attracted widespread attention as a novel material due to their ability to repair themselves after damage. Research suggests that asphalt's self-healing ability stems from the coupling of its temperature dependence, flow characteristics, and usage conditions; at high temperatures, the diffusion and recombination of asphalt molecules can repair microcracks. Many scholars have verified this process through molecular dynamics simulations and rheological experiments, finding that healing efficiency is closely related to temperature, healing time, and asphalt components (such as the ratio of resin to asphaltene).

[0003] Modification technologies for self-healing asphalt include: (1) Induced healing: By incorporating conductive materials such as steel fibers and carbon fibers, local heating is triggered by electromagnetic induction or microwave heating to promote healing. Experiments at Delft University of Technology in the Netherlands show that microwave treatment can achieve a crack healing rate of over 80%. (2) Microcapsule technology: Microcapsules or hollow fibers encapsulating regenerators (such as sunflower oil and aromatic oil) are embedded in asphalt, releasing the repair agent when the crack expands. The urea-formaldehyde wall material microcapsules developed by the Southeast University team can extend fatigue life by 2-3 times. (3) Nanomaterials: Adding silica nanoparticles or carbon nanotubes can improve the mechanical properties of asphalt and accelerate molecular diffusion. Research by the Chinese Academy of Sciences has confirmed that the healing rate of nano-modified asphalt is increased by 30%-50%. However, current bottlenecks include high modification costs, insufficient long-term durability data, low low-temperature self-healing ability, and compatibility with large-scale construction processes. With the increasing demand for sustainable development, bio-based regenerators and low-carbon modification technologies may become key breakthrough directions. Furthermore, existing self-healing pavement materials typically cannot heal under extreme low-temperature conditions, making it difficult to meet practical application requirements.

[0004] The accumulation of waste rubber poses a challenge to sustainable environmental development, and its treatment and value-added utilization have always been industry challenges. Traditional treatment methods such as incineration and landfill not only pollute the environment but also waste valuable rubber resources. Applying waste rubber to road materials can not only improve the performance of asphalt but also achieve resource recycling, making it an important way to create low-carbon, long-life pavements. However, the amount of recycled rubber in asphalt is limited by traditional methods, generally around 20%, and even with de-crosslinking technologies such as desulfurization and degradation, the amount is less than 40%. Patent CN117186658A proposes a method for preparing and using ultra-tough asphalt materials, which prepares ultra-tough asphalt materials through deep de-crosslinking of waste tire rubber. However, the rubber powder used has a mesh size of 15-60 mesh, and the amount of rubber in the asphalt is less than 40%, resulting in relatively insufficient self-healing ability. Therefore, based on the characteristics of rubber's strong low-temperature flow properties and sulfur-containing dynamic bonds, it is necessary to develop road materials with higher self-healing capabilities to improve the lifespan of road surfaces.

[0005] Based on the rubber sol content, the degree of decrosslinking of rubber can be classified into light (sol <30%), medium (sol 30%-50%), deep (50%-70%), and ultra-deep (>70%). Increasing the amount of rubber used in asphalt or replacing asphalt with rubber can significantly improve its low-temperature self-healing ability. Deeply decrosslinked rubber is usually obtained by high-temperature (>300℃) processing using a screw extruder; however, the rubber obtained at this temperature has a strong odor and is difficult to use. Therefore, it is particularly important to find a way to reduce the processing temperature while increasing the degree of rubber pyrolysis to obtain ultra-deeply decrosslinked rubber and achieve its self-healing effect. Summary of the Invention

[0006] The purpose of this invention is to provide a self-healing, long-life pavement material and its preparation method under extremely complex conditions, thereby increasing the added value of waste rubber and solving the problem of widespread pavement cracking under extreme low-temperature conditions. This invention utilizes the pre-degradation of a multi-stage spiral and the thermal shearing action of a multi-stage screw to prepare ultra-deeply decrosslinked rubber. Using this ultra-deeply decrosslinked rubber as the main raw material, the invention reduces the odor from high-temperature extrusion of rubber and increases the amount of rubber used in asphalt. By cleverly utilizing the low-temperature fluidity of this rubber and the dynamic binding of polysulfide bonds after slight vulcanization, a pavement material with excellent self-healing properties under extreme low-temperature conditions is prepared.

[0007] To achieve the above objectives, the following technical solution is provided:

[0008] A long-life pavement material for extremely complex conditions, comprising a base asphalt, an ultra-deep decrosslinked rubber, and a dynamic crosslinking agent; wherein the ultra-deep decrosslinked rubber has a Mooney viscosity of 0-5, a sol content >70%, and a sol number-average molecular weight less than 5000 g / mol, and its content is greater than 50% of the total mass of the base asphalt. The preparation process of the ultra-deep decrosslinked rubber involves: extruding rubber powder made from waste rubber through a multi-stage spiral and a multi-stage screw extruder. The multi-stage spiral consists of at least three sections of spiral auger. It consists of a 2-3 stage screw extrusion mechanism; during multi-stage screw processing, the processing temperature is controlled at 200℃-250℃ and a trace amount of oxygen is introduced, so that the rubber powder becomes sticky due to pre-partial desulfurization before entering the multi-stage screw from the multi-stage screw; during multi-stage screw processing, the processing temperature is controlled at 200℃-260℃, so that the pre-partially desulfurized rubber powder undergoes efficient shear degradation and decrosslinking after entering the high-temperature screw, and finally completes the ultra-deep decrosslinking treatment of the rubber powder, obtaining ultra-deep decrosslinked rubber with Mooney viscosity of 0-5, sol content >70%, and sol number average molecular weight less than 5000g / mol.

[0009] During the preparation of the ultra-deep decrosslinked rubber, the presence of trace amounts of oxygen and temperatures above 200°C during multi-stage spiral processing causes an oxidation reaction on the rubber powder, resulting in partial pre-desulfurization, specifically manifested as increased viscosity. When the pre-desulfurized rubber powder enters the high-temperature screw (approximately 260°C) with an internal temperature exceeding 200°C, the rubber powder undergoes efficient shear degradation and decrosslinking, at which point ultra-deep decrosslinked rubber can be obtained.

[0010] Previously, during the decrosslinking of rubber powder, traditional theory emphasized preventing the breakage of the rubber main chain (in order to maintain the mechanical strength of the rubber). The presence of oxygen would easily lead to the breakage of the rubber main chain. Therefore, a sealed and oxygen-free mode was required during the decrosslinking process. In addition, the presence of oxygen could easily cause carbonization and smoke. However, this application aims to obtain low molecular weight liquid rubber by introducing micro-oxygen for high-efficiency chain scission. This can not only help to decrosslink and actively break the main chain to obtain deeply degraded rubber with high sol content, but also avoid carbonization and smoke.

[0011] Further mixing the deeply decrosslinked rubber with asphalt and performing light crosslinking can yield a self-healing material with excellent properties. Preferably, the mass ratio of the ultra-deeply decrosslinked rubber, the matrix asphalt, and the dynamic crosslinking agent is (50-70):(30-50):(0.1-0.3).

[0012] Preferably, the dynamic crosslinking agent is selected from one or more of the following compounds: sulfur, organic polysulfide compounds (such as Si-75, liquid polysulfide rubber), DTDM, and TMTD. These crosslinking agents can drive the breaking and recombination of dynamic bonds between molecules under stimuli such as heating, light, stress, or changes in ambient humidity, thereby constructing a three-dimensional dynamic network structure with environmental adaptability and self-healing ability between the deeply decrosslinked rubber and the matrix asphalt.

[0013] More preferably, the dynamic crosslinking agent is sulfur.

[0014] Preferably, the base asphalt is 70# or 90# road petroleum asphalt.

[0015] Preferably, the waste rubber includes waste tire rubber or other waste rubber.

[0016] Preferably, the mesh size of the adhesive powder is less than 15 mesh.

[0017] Preferably, the multi-stage spiral is composed of 3 spiral augers, and the multi-stage screw is composed of a 3-stage screw extrusion mechanism; during the processing of the multi-stage spiral, the processing temperature is controlled at 230°C and a trace amount of oxygen is introduced; during the processing of the multi-stage screw, the processing temperature is controlled at 260°C.

[0018] This invention also discloses a method for preparing long-life pavement materials under the aforementioned extreme and complex conditions, comprising the following steps:

[0019] (1) Take the base asphalt and heat it in a mixing tank to melt it. Add the ultra-deep decrosslinked rubber and stir to make the ultra-deep decrosslinked rubber evenly dispersed in the base asphalt, so as to obtain an ultra-deep decrosslinked rubber asphalt mixture.

[0020] (2) Add dynamic crosslinking agent to the ultra-deep decrosslinked rubber asphalt mixture obtained in step (1) and continue stirring to develop and obtain a long-life, crack-free pavement material under extremely complex conditions.

[0021] Preferably, in step (1), the heating temperature of the base asphalt is 130-150 ℃, the stirring swelling temperature is 160-180 ℃, the stirring speed is 100-300 rpm, and the swelling time is 0.5-1 h.

[0022] Preferably, in step (2), the stirring temperature is 160-180 °C, the stirring rate is 400-600 rpm, the stirring time is 0.5-1 h, and the amount of dynamic crosslinking agent is 0.1-0.3 parts by mass.

[0023] More preferably, the dynamic crosslinking agent is sulfur, and the sulfur content is 0.1 to 0.2 parts by mass.

[0024] Preferably, the mass ratio of the ultra-deep decrosslinked rubber, the matrix asphalt, and the dynamic crosslinking agent is (50-70):(30-50):(0.1-0.3).

[0025] The beneficial effects of this invention are:

[0026] The significant advantage of this invention lies in its first systematic utilization of the high flow characteristics of rubber molecular chains under low-temperature conditions and the dynamic reversible bonding characteristics of sulfur bonds (especially polysulfide bonds) in the vulcanization network to construct a novel pavement material capable of self-repair under extremely complex environmental conditions. This invention overcomes the technical bottleneck of traditional asphalt pavement materials becoming brittle and cracked at low temperatures, making them difficult to repair. It achieves structural stability and functional self-sustaining capability under multiple harsh conditions such as cold climates, frequent freeze-thaw cycles, heavy traffic, and complex stress fields.

[0027] Specifically, the rubber phase used in this invention is an ultra-deeply decrosslinked rubber with a Mooney viscosity of 0-5, a sol content >70%, and a sol number-average molecular weight of less than 5000 g / mol. After ultra-deep decrosslinking, the sulfur crosslinks and main chain of the rubber are broken, increasing the reactivity of the rubber with asphalt. Moreover, the main chain of the rubber itself is composed of flexible segments such as polyisoprene or styrene-butadiene rubber. Although the overall chain movement is restricted at low temperatures, it still possesses the ability of micro-Brownian motion of local segments, i.e., "low-temperature fluidity." When the rubber becomes an ultra-deeply decrosslinked rubber, its low-temperature fluidity is even better. At the same time, by precisely controlling the vulcanization system (such as using sulfur donors, optimizing the accelerator ratio, and using dynamic vulcanization processes), a transition layer rich in a dynamic polysulfide crosslinking network is constructed in the interface region between the rubber particles and the asphalt matrix. Under the stimulation of external stress, local energy concentration caused by microcracks, or temperature fluctuations, the sulfur-sulfur bonds (S-S) and carbon-sulfur bonds (C-S) in this network can undergo reversible homolytic or heterolytic cracking, and recombine after stress relaxation, realizing the dynamic reconstruction of the crosslinking structure.

[0028] This synergistic mechanism of "low-temperature fluidity of molecular chains" and "dynamic recombination of sulfur bonds" enables the material to achieve crack tip passivation, interface re-adhesion, and local network reconstruction through molecular-scale bond exchange and chain segment rearrangement when micro-damage occurs, without external intervention. This significantly improves the material's fatigue life and crack resistance. Especially in low-temperature winter environments (such as −20°C to 0°C), traditional asphalt materials almost lose their self-healing ability, while the material of this invention can still maintain a certain degree of self-healing kinetics, filling the technological gap in the application of existing road materials in cold regions.

[0029] Furthermore, the dynamic cross-linked network designed in this invention possesses both excellent thermal stability and chemical durability. It does not soften or fail rheologically due to excessive activation of sulfur bonds during high-temperature seasons, achieving a performance balance across a wide temperature range (−30°C to 70°C). This material is not only suitable for critical components such as newly constructed high-grade highways, bridge expansion joint areas, and airport runways, but can also be used for the recycling and upgrading of old road surfaces, demonstrating significant environmental benefits and promising engineering applications.

[0030] In summary, the core innovation of this invention lies in controlling and deepening the degradation depth of rubber, enabling the first systematic and comprehensive combination of the low-temperature fluidity of rubber molecular chains and the dynamic covalent characteristics of sulfur bonds. This fully utilizes the low-temperature fluidity of rubber molecular chains and the dynamic binding characteristics of sulfur bonds to construct road engineering materials with environmentally adaptable self-healing capabilities. Furthermore, it endows traditional asphalt matrices with "life-like" damage response capabilities at the molecular mechanism level, representing a new direction in the development of intelligent road materials. In addition, it allows for the high-value recycling of waste rubber. Moreover, the ultra-deep decrosslinking of rubber breaks sulfur crosslinks and the main chain, increasing the reactivity between tire rubber and asphalt, solving problems such as low rubber powder content, excessively high viscosity, and construction difficulties in traditional rubber-asphalt systems. Furthermore, the self-healing of asphalt pavements can significantly extend their service life, providing a feasible and low-cost solution for constructing long-life, crack-free pavements. It is highly practical and has significant economic and social value. Attached Figure Description

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0032] Figure 1 This is a diagram showing the state of the adhesive powder before treatment.

[0033] Figure 2 The diagram shows the state of the shallowly decrosslinked rubber obtained after shallow decrosslinking treatment of rubber powder.

[0034] Figure 3 This is a state diagram of deeply decrosslinked rubber obtained after deep decrosslinking treatment of existing rubber powder;

[0035] Figure 4 This is a state diagram of the ultra-deep decrosslinked rubber obtained after ultra-deep decrosslinking treatment of rubber powder in this invention;

[0036] Figure 5 This is a diagram showing the state of the adhesive powder in this invention before it enters the multi-stage screw from the multi-stage spiral, after it has become sticky due to partial pre-desulfurization. Detailed Implementation

[0037] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0038] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features for a similar purpose, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0039] Preparation of ultra-deeply decrosslinked rubber with Mooney viscosity of 0–5, sol content >70%, and sol number-average molecular weight less than 5000 g / mol:

[0040] Rubber powder with a mesh size of less than 15, made from waste rubber, is extruded sequentially through a multi-stage spiral and a multi-stage screw extruder. The multi-stage spiral consists of three sections of spiral auger, and the multi-stage screw is a three-stage screw extruder. During multi-stage spiral processing, the processing temperature is controlled at 230°C, and a trace amount of oxygen is introduced, so that the rubber powder becomes viscous due to pre-partial desulfurization before entering the multi-stage screw. During multi-stage screw processing, the processing temperature is controlled at 260°C, so that the pre-partially desulfurized rubber powder undergoes efficient shear degradation and decrosslinking after entering the high-temperature screw, ultimately completing the ultra-deep decrosslinking treatment of the rubber powder, obtaining ultra-deeply decrosslinked rubber with a Mooney viscosity of 0-5, a sol content >70%, and an average sol molecular weight of 4700 g / mol.

[0041] like Figure 1 The diagram shown is a schematic of the state of the adhesive powder before treatment; it is in the form of powdery particles.

[0042] like Figure 2 The figure shows the state diagram of the shallowly decrosslinked rubber obtained after shallow decrosslinking treatment of rubber powder. As can be seen from the figure, it is very viscous and very difficult to mix with the base asphalt.

[0043] like Figure 3 The figure shows the state diagram of the deep decrosslinked rubber obtained after deep decrosslinking treatment of existing rubber powder. As can be seen from the figure, it is a relatively viscous paste-like substance. Because its viscosity is still high, it usually needs to be discharged, stored and used in the form of quick-dissolving granules, and it is still difficult to mix with the base asphalt.

[0044] like Figure 4 The figure shows the state diagram of the ultra-deep decrosslinked rubber obtained after the ultra-deep decrosslinking treatment of the rubber powder in this invention. As can be seen from the figure, it is a highly fluid putty-like substance that is very easy to mix with the base asphalt.

[0045] like Figure 5The diagram shows the state of the rubber powder before it enters the multi-stage screw in the multi-stage screw, after it has become sticky due to partial pre-desulfurization. After being pre-treated to this state, it enters the multi-stage screw for reactive extrusion, ultimately achieving ultra-deep decrosslinking of the rubber powder.

[0046] Therefore, the ultra-deeply decrosslinked rubber obtained by this invention has low viscosity and low crosslinking degree upon discharge, exhibiting a highly fluid, paste-like consistency. Figure 4 As shown in the image, it mixes very easily with the base asphalt, so shearing and stirring are unnecessary; only swelling and stirring are required, saving processing time and costs, and reducing aging. Because the ultra-deeply decrosslinked rubber obtained by this invention has a low viscosity, the sulfur crosslinks and main chain are broken more thoroughly after ultra-deep decrosslinking, further increasing the reactivity of the rubber with asphalt. Therefore, the dosage can be increased, resulting in better self-healing ability and longer lifespan under extreme conditions.

[0047] Blank example 1:

[0048] Conventional SBS modified asphalt. 70# base asphalt is modified with 4% SBS.

[0049] Blank example 2:

[0050] The content of high Mooney viscosity decrosslinked recycled rubber (Mouney viscosity of 80) is 50 parts by mass, the content of 70# base asphalt is 50 parts by mass, and the content of sulfur is 0.2 parts by mass.

[0051] Take 500 g of 70# base asphalt and heat it at 150 ℃ until it is completely fluid. Then add 500 g of decrosslinked reclaimed rubber with a Mooney viscosity of 80. Swell and dissolve it at 180 ℃ for 0.5 h. Then shear it at 5000 rpm for 1 h. Stir it at 500 rpm for 0.5 h. Add 2 g of sulfur and continue stirring for 0.5 h to prepare modified asphalt with high Mooney viscosity decrosslinked rubber.

[0052] Comparative Example 1:

[0053] The ultra-deep decrosslinked rubber prepared above has an ultra-deep decrosslinked rubber content of 20 parts by mass, a 70# base asphalt content of 80 parts by mass, and a sulfur content of 0.2 parts by mass.

[0054] 800g of 70# base asphalt was heated at 150 ℃ until it was completely fluid. Then, 200g of ultra-deep decrosslinked rubber was added, and the mixture was stirred at 180 ℃ for 0.5 h to swell and dissolve it. The stirring speed was 200 rpm to uniformly disperse the ultra-deep decrosslinked rubber in the base asphalt, thus obtaining an ultra-deep decrosslinked rubber asphalt mixture. Then, 2g of sulfur was added to the ultra-deep decrosslinked rubber asphalt mixture, and the mixture was stirred at 180 ℃ and 500 rpm for 0.5 h to prepare a low-content ultra-deep decrosslinked rubber modified asphalt.

[0055] Comparative Example 2:

[0056] The ultra-deep decrosslinked rubber prepared above has an ultra-deep decrosslinked rubber content of 50 parts by mass, a 70# base asphalt content of 50 parts by mass, and a sulfur content of 0.2 parts by mass.

[0057] 500g of 70# base asphalt was heated at 150 ℃ until it was completely fluid. Then, 500g of ultra-deep decrosslinked rubber was added, and the mixture was stirred at 180 ℃ for 0.5 h to swell and dissolve. The stirring speed was 200 rpm to uniformly disperse the ultra-deep decrosslinked rubber in the base asphalt, thus obtaining an ultra-deep decrosslinked rubber asphalt mixture. Then, 2g of sulfur was added to the ultra-deep decrosslinked rubber asphalt mixture, and the mixture was stirred at 180 ℃ and 500 rpm for another 0.5 h to prepare a high-content ultra-deep decrosslinked rubber modified asphalt.

[0058] Comparative Example 3:

[0059] The ultra-deep decrosslinked rubber prepared above has an ultra-deep decrosslinked rubber content of 70 parts by mass, a 70# base asphalt content of 30 parts by mass, and a sulfur content of 0.2 parts by mass.

[0060] 300 g of 70# base asphalt was heated at 150 ℃ until it was completely fluid. Then, 700 g of ultra-deep decrosslinked rubber was added, and the mixture was stirred at 180 ℃ for 0.5 h to swell and dissolve. The stirring speed was 200 rpm to uniformly disperse the ultra-deep decrosslinked rubber in the base asphalt, thus obtaining an ultra-deep decrosslinked rubber asphalt mixture. Then, 2 g of sulfur was added to the ultra-deep decrosslinked rubber asphalt mixture, and the mixture was stirred at 180 ℃ and 500 rpm for 0.5 h to prepare ultra-high content ultra-deep decrosslinked rubber modified asphalt.

[0061] Heating efficiency of five modified asphalts at low temperature (-10 ℃)

[0062] Blank example 1 Blank example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Healing efficiency (%) 0 0 10.0 55.5 62.0

[0063] Heating efficiency of five types of modified asphalt after aging at low temperature (-10 ℃)

[0064] Blank example 1 Blank example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Healing efficiency (%) 0 0 0 30.5 42.5

[0065] The above results demonstrate that the long-life pavement material and its preparation method under extreme and complex conditions provided by this invention significantly improve the self-healing performance of asphalt materials in low-temperature environments by preparing and introducing ultra-deep decrosslinking rubber. Compared with blank examples 1 and 2, comparative examples 1-3 all exhibit healing capabilities at low temperatures, with comparative example 2 showing a healing efficiency exceeding 50% and comparative example 3 reaching a healing efficiency of 62.0%, far exceeding that of comparative example 1. Even after aging, the healing efficiencies of comparative examples 2 and 3 remain >30%. This excellent low-temperature self-healing performance enables asphalt pavements to autonomously repair micro-cracks under cold climate conditions, effectively delaying the development of pavement defects and extending the service life of the pavement. These advantages enable this invention not only to meet the stringent requirements for material performance in long-life pavement engineering but also to demonstrate significant advantages in special application scenarios such as cold-region road construction and heavy-load traffic roads, exhibiting significant economic benefits and broad prospects for widespread application.

[0066] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A long-life pavement material under extremely complex conditions, characterized in that, The long-life pavement material is mainly made from a mixture of base asphalt, ultra-deep decrosslinked rubber, and dynamic crosslinking agent. The ultra-deep decrosslinked rubber has a Mooney viscosity of 0-5, a sol content >70%, and a sol number-average molecular weight less than 5000 g / mol. Its content is greater than 50% of the total mass of the base asphalt. The process for preparing the ultra-deep decrosslinked rubber involves extruding rubber powder made from waste rubber through a multi-stage spiral and a multi-stage screw extruder. The multi-stage spiral consists of at least three spiral auger sections, and the multi-stage screw extruder consists of two to three stages. The process involves: during multi-stage spiral processing, the processing temperature is controlled at 200℃-250℃ and a trace amount of oxygen is introduced, allowing the rubber powder to become viscous due to pre-partial desulfurization before entering the multi-stage screw from the multi-stage spiral; during multi-stage screw processing, the processing temperature is controlled at 200℃-260℃, allowing the pre-partially desulfurized rubber powder to undergo efficient shear degradation and decrosslinking after entering the high-temperature screw, ultimately completing the ultra-deep decrosslinking treatment of the rubber powder, obtaining ultra-deep decrosslinked rubber with a Mooney viscosity of 0-5, a sol content >70%, and a sol number-average molecular weight of less than 5000 g / mol.

2. The long-life pavement material under extremely complex conditions according to claim 1, characterized in that, The mass ratio of the ultra-deep decrosslinked rubber, the matrix asphalt, and the dynamic crosslinking agent is (50-70):(30-50):(0.1-0.3).

3. The long-life pavement material under extremely complex conditions according to claim 1, characterized in that, The dynamic crosslinking agent is selected from one or more of the following classes of compounds: sulfur, organic polysulfides, DTDM, and TMTD.

4. The long-life pavement material under extremely complex conditions according to claim 3, characterized in that, The dynamic crosslinking agent is sulfur.

5. The long-life pavement material under extremely complex conditions according to claim 1, characterized in that, The base asphalt is 70# or 90# road petroleum asphalt.

6. The long-life pavement material under extremely complex conditions according to claim 1, characterized in that, The mesh size of the adhesive powder is less than 15 mesh.

7. The long-life pavement material under extremely complex conditions according to claim 1, characterized in that, The multi-stage spiral consists of 3 spiral auger sections, and the multi-stage screw consists of a 3-stage screw extrusion mechanism. During the processing of the multi-stage spiral, the processing temperature is controlled at 230°C and a trace amount of oxygen is introduced. During the processing of the multi-stage screw, the processing temperature is controlled at 260°C.

8. A method for preparing a long-life pavement material under extremely complex conditions as described in any one of claims 1-7, characterized in that, Includes the following steps: (1) Take the base asphalt and heat it in a mixing tank to melt it. Add the ultra-deep decrosslinked rubber and stir to make the ultra-deep decrosslinked rubber evenly dispersed in the base asphalt, so as to obtain an ultra-deep decrosslinked rubber asphalt mixture. (2) Add dynamic crosslinking agent to the ultra-deep decrosslinked rubber asphalt mixture obtained in step (1) and continue stirring to develop and obtain long-life pavement material under extreme complex conditions.

9. The method for preparing a long-life pavement material under extremely complex conditions according to claim 8, characterized in that, In step (1), the heating temperature of the base asphalt is 130-150 ℃, the stirring swelling temperature is 160-180 ℃, the stirring speed is 100-300 rpm, and the swelling time is 0.5-1 h.

10. The method for preparing a long-life pavement material under extremely complex conditions according to claim 8, characterized in that, In step (2), the stirring temperature is 160-180 ℃, the stirring rate is 400-600 rpm, the stirring time is 0.5-1 h, and the amount of dynamic crosslinking agent is 0.1-0.3 parts by mass.

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