Anti-cracking asphalt surface material, its preparation method and use

Abstract

The application belongs to the field of road engineering materials, and provides an anti-cracking asphalt surface layer material and a preparation method and application thereof, the application adopts a preparation process of pretreatment of base asphalt under nitrogen protection, dispersing of a modifier, grafting of a compatilizer, crosslinking reaction and aging and discharging, a double-network modified structure is constructed by a styrene-butadiene-styrene elastomer and an ethylene-methyl methacrylate copolymer ionomer, excellent performances of a penetration of 40-60, a softening point of greater than or equal to 75 DEG C, an elongation of greater than or equal to 30 cm, a 60s stiffness modulus of less than or equal to 300 MPa, a creep rate of greater than or equal to 0.30, a fatigue life of greater than or equal to 10 6 times, an elastic recovery rate of greater than or equal to 75%, a Marshall stability of greater than or equal to 8 kN and a dynamic stability of greater than or equal to 3000 times / mm are realized, the problems of insufficient anti-cracking and anti-rutting performances of a traditional asphalt surface layer are solved, and the application has important road engineering application value.

Description

Technical Field

[0001] This invention relates to the field of road materials, specifically to a crack-resistant asphalt pavement material, its preparation method, and its applications. Background Technology

[0002] With the rapid development of my country's transportation infrastructure and the continuous growth of heavy traffic volume, the performance requirements for asphalt pavement, as a key structural layer directly bearing vehicle loads and environmental effects, are becoming increasingly stringent. Under high-temperature, heavy-load traffic conditions, asphalt pavement needs excellent rutting resistance to prevent permanent deformation and ensure road smoothness and driving safety. Under low-temperature environments and temperature cycling, asphalt pavement must have good crack resistance to prevent reflective and temperature cracking, ensuring the integrity and service life of the pavement structure. Simultaneously, facing complex and variable climatic conditions and heavy traffic loads, asphalt pavement materials also need to exhibit excellent comprehensive performance in terms of fatigue resistance, water stability, and durability. Meeting these key performance requirements can not only significantly improve road quality and service levels, extend pavement service life, and reduce maintenance costs, but also promote the innovative development of road engineering materials technology, providing important material support for building a high-quality transportation infrastructure system, and has significant engineering application value and socio-economic significance.

[0003] The current state of development of asphalt surface materials indicates that traditional modified asphalt still has significant shortcomings in terms of crack resistance and rutting resistance. The fundamental reason lies in the difficulty of achieving effective structural design and performance coordination at the molecular level with existing modification technologies. For example, Chinese patent CN112679146A discloses a high-temperature rutting-resistant asphalt mixture, but it suffers from insufficient low-temperature crack resistance. While traditional SBS-modified asphalt can improve the high and low temperature performance of asphalt to some extent, the limited compatibility between SBS and asphalt leads to phase separation at high temperatures, resulting in a decrease in rutting resistance. At low temperatures, the modified asphalt becomes more brittle, reducing its crack resistance. Furthermore, conventional modification methods mainly rely on physical blending, lacking effective chemical crosslinking and network structure construction, resulting in insufficiently durable and stable modification effects. For instance, Chinese patent CN104387782B discloses a crack-resistant road asphalt and its preparation method, but it suffers from the problem of difficulty in simultaneously achieving high-temperature rutting resistance and low-temperature crack resistance. The existence of these technical limitations makes existing asphalt pavement materials inadequate in the face of increasingly stringent usage environments and performance requirements, and there is an urgent need to develop new asphalt pavement materials with excellent comprehensive performance in crack resistance and rutting resistance. Summary of the Invention

[0004] (1) Technical problems to be solved

[0005] The purpose of this invention is to provide a crack-resistant asphalt pavement material, its preparation method and application, to solve the current problems of asphalt pavement materials in terms of crack resistance and rutting resistance.

[0006] (2) Technical solution

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing a crack-resistant asphalt pavement material, the entire process being carried out under nitrogen protection, includes the following steps:

[0009] S1 base asphalt pretreatment: Heat the base asphalt to 160-165℃, add styrene-butadiene-styrene thermoplastic elastomer and disperse under high shear for 30-35 minutes;

[0010] S2 modifier dispersion: Add ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40-50% and zinc-based coordination agent, and disperse the reaction at a temperature of 160-175℃ for 20-30 minutes.

[0011] S3 compatibilizer grafting: Add reactive compatibilizer and carry out grafting reaction for 15-25 min, then continue to add polyhydroxy compound and disperse evenly at 160-170℃ for 15-20 min;

[0012] S4 crosslinking reaction: Add an exchange catalyst and carry out a low-shear reaction at 165-175℃ for 35-50 min to form a crosslinked network structure;

[0013] S5 maturation discharge: discharge after maturation at 155-172℃ for 35-50 minutes.

[0014] Furthermore, in step S1, the high-shear dispersion speed is 6000-8000 rpm, the water content of the system is less than 0.1%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 4-5% of the mass of the base asphalt.

[0015] Further, in step S2, the amount of ethylene-methacrylic acid copolymer ionomer added is 2.5-4% of the mass of the base bitumen, the zinc-based coordination aid is at least one of zinc oxide, zinc acetate, zinc stearate or zinc naphthenate, the amount added is 0.8-1.5% of the mass of the ionomer, and the dispersion speed is 2000-4000 rpm.

[0016] Furthermore, the reactive compatibilizer mentioned in step S3 is at least one of maleic anhydride-grafted polypropylene or maleic anhydride-grafted polyethylene, and the amount added is 0.8-1.5% of the mass of the base asphalt.

[0017] The polyhydroxy compound is at least one of pentaerythritol, citric acid, or glycerol, and the amount added is 15-25% of the mass of the reactive compatibilizer, with a stirring speed of 2000-4000 rpm.

[0018] Furthermore, in step S4, the reaction temperature is 169-172℃, the low-shear stirring rate is 120-160 rpm, and the exchange catalyst is at least one of zinc acetate, stannous octoate, or tetrabutyl titanate, with an addition amount of 0.2-0.8% of the mass of the polyhydroxy compound.

[0019] Furthermore, a closed reactor is adopted, which has a temperature control system and the discharge temperature is 155-160℃.

[0020] This invention employs a five-step, staged preparation process under nitrogen protection, primarily used to enhance the crack resistance and rutting resistance of asphalt surface materials. The matrix asphalt pretreatment step utilizes a high-shear dispersion of styrene-butadiene-styrene thermoplastic elastomer to form a uniform elastic phase distribution within the asphalt matrix, laying the foundation for subsequent modification. The modifier dispersion stage introduces an ionomer of ethylene-methacrylic acid copolymer with a neutralization degree of 40-50%, combined with the synergistic effect of a zinc-based coordination aid, to construct an ion-associative network structure in the asphalt system, significantly improving the material's high-temperature deformation resistance. The compatibilizer grafting step improves the interfacial compatibility between different components through the chemical reaction of maleic anhydride grafted onto polypropylene or maleic anhydride grafted onto polyethylene. The introduction of polyhydroxy compounds provides active sites for subsequent crosslinking reactions. In the crosslinking reaction stage, under the action of an exchange catalyst, a stable three-dimensional crosslinked network structure is formed, achieving an organic combination of the elastomer network and the ionomer network, constructing a dual-network modified system that combines elastic recovery and rigid support. Throughout the preparation process, a nitrogen-protected environment effectively prevents oxidative degradation, and the temperature control system of the sealed reactor ensures the full progress of each reaction step. This multi-component synergistic modification mechanism enables the material to maintain excellent low-temperature flexibility while significantly enhancing high-temperature stability, achieving an effective balance between crack resistance and rutting resistance.

[0021] The present invention also discloses a crack-resistant asphalt surface material, which is composed of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40-50%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound and exchange catalyst.

[0022] Furthermore, the content of styrene-butadiene-styrene thermoplastic elastomer is 4-5% of the mass of the base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 2.5-4% of the mass of the base asphalt, the content of reactive compatibilizer is 0.8-1.5% of the mass of the base asphalt, the content of zinc-based coordination aid is 0.8-1.5% of the mass of the ionomer, the content of polyhydroxy compound is 15-25% of the mass of the reactive compatibilizer, and the content of exchange catalyst is 0.2-0.8% of the mass of the polyhydroxy compound.

[0023] Furthermore, the material has an elastomer-ionomer dual-network modified structure, with a penetration of 40-60 (0.1 mm) at 25℃, 100 g, and 5 s. The softening point by the ring and ball method is ≥75℃, and the ductility at 15℃ is ≥30 cm. Moreover, in the bending beam rheometer test at -12℃, the stiffness modulus at 60 s is less than or equal to 300 MPa, and the creep rate is ≥0.30.

[0024] The composite modulus G* was 2.0-5.0 kPa in the dynamic shear rheological test at 64℃, and the fatigue life was ≥10 kPa in the fatigue test at 25℃. 6 The elastic recovery rate is ≥75%.

[0025] The use of a crack-resistant asphalt surface material in the preparation of road surface layers is characterized in that the material is used to prepare crack-resistant road surface layers with a road surface Marshall stability ≥8kN, low-temperature bending failure strain ≥2500με, and high-temperature rutting dynamic stability ≥3000 cycles / mm.

[0026] This invention employs an elastomer-ionomer dual-network modified structure primarily to enhance the overall crack resistance and rutting resistance of asphalt pavement materials. The material utilizes a styrene-butadiene-styrene thermoplastic elastomer to construct a flexible elastic network, providing excellent low-temperature deformation capacity and elastic recovery. Simultaneously, the introduction of ethylene-methacrylic acid copolymer ionomers with a neutralization degree of 40-50% forms a rigid ionic association network, significantly enhancing the material's high-temperature deformation resistance. The synergistic effect of zinc-based coordination aids and ionomers strengthens the ionic association effect, further improving the stability of the network structure. Reactive compatibilizers improve the compatibility of different phase interfaces through chemical grafting reactions, while polyhydroxy compounds provide active crosslinking sites for the crosslinking reaction, forming a stable three-dimensional crosslinked structure under the action of an exchange catalyst. This dual-network synergistic mechanism enables the material to maintain good penetration and ductility while possessing excellent softening point and stiffness modulus characteristics, achieving an effective balance between low-temperature crack resistance and high-temperature rutting resistance. The coordinated improvement of key indicators such as composite modulus, fatigue life and elastic recovery rate of the material ensures that it can meet the stringent requirements of Marshall stability, low temperature bending failure strain and high temperature rutting dynamic stability in road applications, demonstrating the performance enhancement effect brought about by multi-component synergistic modification.

[0027] (3) Beneficial technical effects

[0028] 1. Significantly improves low-temperature crack resistance: By constructing a flexible elastic network through styrene-butadiene-styrene thermoplastic elastomer and combining it with chemical grafting modification of reactive compatibilizer, the low-temperature flexibility and deformation capacity of the material are significantly improved. In the bending beam rheometer test at -12℃, the stiffness modulus at 60s is less than or equal to 300MPa, the creep rate is ≥0.30, and the ductility at 15℃ is ≥30cm, effectively preventing the occurrence of road surface cracking problems in low-temperature environments.

[0029] 2. Excellent high-temperature rutting resistance: A rigid ion-associative network is constructed through the synergistic effect of ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40-50% and zinc-based coordination agent, which significantly enhances the material's high-temperature stability and resistance to permanent deformation. The softening point by the ring and ball method is ≥75℃, the composite modulus G* in the dynamic shear rheological test at 64℃ is 2.0-5.0kPa, and the high-temperature rutting dynamic stability is ≥3000 times / mm, effectively resisting rutting deformation under heavy traffic conditions.

[0030] 3. Excellent fatigue resistance and elastic recovery: Through the synergistic effect of the elastomer-ionomer dual-network modified structure, the material exhibits a fatigue life ≥10°C in a 25°C fatigue test. 6 The elastic recovery rate is ≥75%, which significantly improves the material's ability to resist repeated loads, extends the service life of the road surface, and reduces maintenance costs.

[0031] 4. Stable and controllable preparation process: The five-step phased preparation process under nitrogen protection, through the precise temperature control system of the sealed reaction vessel, ensures that each component reacts fully under the most suitable temperature and time conditions, effectively prevents oxidative degradation, and guarantees the stability and reproducibility of product quality, providing a reliable technical guarantee for industrial production.

[0032] 5. Comprehensive improvement in road performance: The material exhibits excellent overall road performance in road applications, with a penetration of 40-60, Marshall stability ≥8kN, and low-temperature bending failure strain ≥2500με. It achieves an effective balance between high and low temperature performance and meets the increasingly stringent performance requirements of modern road engineering for asphalt pavement materials. Attached Figure Description

[0033] Figure 1 This invention relates to the effect of SBS content on the stiffness modulus and Marshall stability of S(60).

[0034] Figure 2 This invention relates to the effect of the degree of neutralization of the ionomer on the stiffness modulus and Marshall stability of S(60).

[0035] Figure 3 This invention relates to the effect of crosslinking reaction temperature on complex modulus G* and fatigue life.

[0036] Figure 4 This invention investigates the effect of the catalyst content on the complex modulus G* and fatigue life.

[0037] Figure 5 The changes in the infrared Fourier spectrum of the synthesized product during the synthesis process in Example 2 of this invention are shown.

[0038] Figure 6 The stiffness modulus of S(60) and Marshall stability are compared for embodiments and comparative examples of the present invention.

[0039] Figure 7 This is a comparison of complex modulus and fatigue life in the embodiments and comparative examples of the present invention.

[0040] Figure 8 This is a comparison of the m value and glass transition temperature for embodiments and comparative examples of the present invention.

[0041] Figure 9 This is a comparison of the RTFOT quality change rate between the embodiments and comparative examples of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0043] Example 1:

[0044] A method for preparing a crack-resistant asphalt surface material, the entire process is carried out under nitrogen protection, including the following steps: S1 Base asphalt pretreatment: The base asphalt is heated to 162℃, and styrene-butadiene-styrene thermoplastic elastomer is added for high-shear dispersion for 32 min; S2 Modifier dispersion: Ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 45% and zinc-based coordination aid are added, and the dispersion reaction is controlled at 168℃ for 25 min; S3 Compatibilizer grafting: A reactive compatibilizer is added for grafting reaction for 20 min, followed by the addition of a polyhydroxy compound, and uniform dispersion is carried out at 165℃ for 18 min; S4 Crosslinking reaction: An exchange catalyst is added, and a low-shear reaction is carried out at 170℃ for 42 min to form a crosslinked network structure; S5 Curing and discharge: The material is discharged after curing at 163℃ for 42 min. In step S1, the high-shear dispersion speed is 7000 rpm, the system water content is 0.05%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 4.5% of the mass of the base asphalt. In step S2, the amount of ethylene-methacrylic acid copolymer ionomer added in this embodiment is 3.2% of the mass of the base asphalt, the zinc-based coordination aid in this embodiment is zinc oxide, and the amount added is 1.1% of the mass of the ionomer in this embodiment, and the dispersion speed is 3000 rpm. In step S3, the reactive compatibilizer in this embodiment is maleic anhydride-grafted polypropylene, and the amount added is 1.2% of the mass of the base asphalt; the polyhydroxy compound in this embodiment is pentaerythritol, and the amount added is 20% of the mass of the reactive compatibilizer in this embodiment, and the stirring speed is 3000 rpm. In step S4, the reaction temperature is 170℃, the low-shear stirring rate is 140 rpm, the exchange catalyst in this embodiment is zinc acetate, and the amount added is 0.5% of the mass of the polyhydroxy compound in this embodiment. A closed reactor is used, the reactor has a temperature control system, and the discharge temperature is 158℃.

[0045] The crack-resistant asphalt surface material prepared in this embodiment consists of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 45%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound, and exchange catalyst. The content of styrene-butadiene-styrene thermoplastic elastomer is 4.5% of the mass of base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 3.2% of the mass of base asphalt, the content of reactive compatibilizer is 1.2% of the mass of base asphalt, the content of zinc-based coordination aid is 1.1% of the mass of the ionomer in this embodiment, the content of polyhydroxy compound is 20% of the mass of the reactive compatibilizer in this embodiment, and the content of exchange catalyst is 0.5% of the mass of the polyhydroxy compound in this embodiment. The material in this embodiment has an elastomer-ionomer dual-network modified structure. At 25°C, with a weight of 100g and a 5s timeframe, it exhibits a penetration of 50, a softening point of 78°C using the ring and ball method, and a ductility of 35cm at 15°C. Furthermore, in a -12°C bending beam rheometer test, the material demonstrates a stiffness modulus of 280MPa over 60s and a creep rate of 0.35; a composite modulus G* of 3.5kPa in a 64°C dynamic shear rheological test; and a fatigue life of 1.2×10⁻⁶ kPa in a 25°C fatigue test. 6 The elastic recovery rate is 78%. The crack-resistant asphalt pavement material of this embodiment is used to prepare crack-resistant road pavement, with a pavement Marshall stability of 9.2kN, a low-temperature bending failure strain of 2800με, and a high-temperature rutting dynamic stability of 3500 cycles / mm.

[0046] This embodiment adopts a conservative and stable medium parameter configuration, with each process parameter selected at the middle of its range to ensure the stability and reproducibility of the production process. The material has a good balance of comprehensive performance and is suitable for large-scale industrial production and standard road construction projects.

[0047] Example 2:

[0048] A method for preparing a crack-resistant asphalt surface material, the entire process is carried out under nitrogen protection, including the following steps: S1 Base asphalt pretreatment: heating the base asphalt to 160℃, adding styrene-butadiene-styrene thermoplastic elastomer and dispersing under high shear for 35 min; S2 Modifier dispersion: adding ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40% and zinc-based coordination aid, and dispersing at 160℃ for 30 min; S3 Compatibilizer grafting: adding reactive compatibilizer and grafting reaction for 25 min, followed by adding polyhydroxy compounds and uniformly dispersing at 160℃ for 20 min; S4 Crosslinking reaction: adding exchange catalyst and performing low shear reaction at 165℃ for 50 min to form a crosslinked network structure; S5 Curing and discharging: curing at 155℃ for 50 min and then discharging. In step S1, the high-shear dispersion speed is 8000 rpm, the system water content is 0.08%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 5% of the mass of the base asphalt. In step S2, the amount of ethylene-methacrylic acid copolymer ionomer added in this embodiment is 2.5% of the mass of the base asphalt, the zinc-based coordination aid in this embodiment is zinc naphthenate, and the amount added is 0.8% of the mass of the ionomer in this embodiment, and the dispersion speed is 2000 rpm. In step S3, the reactive compatibilizer in this embodiment is maleic anhydride-grafted polyethylene, and the amount added is 1.5% of the mass of the base asphalt; the polyhydroxy compound in this embodiment is glycerol, and the amount added is 25% of the mass of the reactive compatibilizer in this embodiment, and the stirring speed is 2000 rpm. In step S4, the reaction temperature is 165℃, the low-shear stirring rate is 120 rpm, the exchange catalyst in this embodiment is stannous octoate, and the amount added is 0.8% of the mass of the polyhydroxy compound in this embodiment. A closed reactor is used, the reactor has a temperature control system, and the discharge temperature is 155℃.

[0049] The crack-resistant asphalt surface material prepared in this embodiment consists of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound, and exchange catalyst. The content of styrene-butadiene-styrene thermoplastic elastomer is 5% of the mass of the base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 2.5% of the mass of the base asphalt, the content of reactive compatibilizer is 1.5% of the mass of the base asphalt, the content of zinc-based coordination aid is 0.8% of the mass of the ionomer in this embodiment, the content of polyhydroxy compound is 25% of the mass of the reactive compatibilizer in this embodiment, and the content of exchange catalyst is 0.8% of the mass of the polyhydroxy compound in this embodiment. The material in this embodiment has an elastomer-ionomer dual-network modified structure. At 25°C, 100g, and 5s, its penetration is 55, its softening point using the ring and ball method is 75°C, and its ductility at 15°C is 42cm. Furthermore, in a -12°C bending beam rheometer test, the material exhibits a stiffness modulus of 250MPa and a creep rate of 0.42 after 60s; a composite modulus G* of 2.2kPa in a 64°C dynamic shear rheological test; and a fatigue life of 1.5×10⁻⁶ kPa in a 25°C fatigue test. 6 The elastic recovery rate is 82%. The crack-resistant asphalt pavement material of this embodiment is used to prepare crack-resistant road pavement, with a pavement Marshall stability of 8.5kN, a low-temperature bending failure strain of 3200με, and a high-temperature rutting dynamic stability of 3200 cycles / mm.

[0050] This embodiment focuses on optimizing low-temperature crack resistance by using a higher elastomer content and a longer reaction time to enhance the material's low-temperature flexibility and deformation capacity, making it suitable for applications in cold regions, roads, and environments with drastic temperature changes.

[0051] Example 3:

[0052] A method for preparing a crack-resistant asphalt surface material, the entire process is carried out under nitrogen protection, including the following steps: S1 Base asphalt pretreatment: heating the base asphalt to 165℃, adding styrene-butadiene-styrene thermoplastic elastomer and dispersing under high shear for 30 min; S2 Modifier dispersion: adding ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 50% and zinc-based coordination aid, and dispersing at 175℃ for 20 min; S3 Compatibilizer grafting: adding reactive compatibilizer and grafting for 15 min, followed by adding polyhydroxy compounds and uniformly dispersing at 170℃ for 15 min; S4 Crosslinking reaction: adding an exchange catalyst and performing a low shear reaction at 175℃ for 35 min to form a crosslinked network structure; S5 Curing and discharging: curing at 172℃ for 35 min and then discharging. In step S1, the high-shear dispersion speed is 6000 rpm, the system water content is 0.03%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 4% of the mass of the base asphalt. In step S2, the amount of ethylene-methacrylic acid copolymer ionomer added in this embodiment is 4% of the mass of the base asphalt, the zinc-based coordination aid in this embodiment is zinc stearate, the amount added is 1.5% of the mass of the ionomer in this embodiment, and the dispersion speed is 4000 rpm. In step S3, the reactive compatibilizer in this embodiment is maleic anhydride-grafted polypropylene, the amount added is 0.8% of the mass of the base asphalt; the polyhydroxy compound in this embodiment is citric acid, the amount added is 15% of the mass of the reactive compatibilizer in this embodiment, and the stirring speed is 4000 rpm. In step S4, the reaction temperature is 175℃, the low-shear stirring rate is 160 rpm, the exchange catalyst in this embodiment is tetrabutyl titanate, the amount added is 0.2% of the mass of the polyhydroxy compound in this embodiment. A closed reactor is used, the reactor has a temperature control system, and the discharge temperature is 160℃.

[0053] The crack-resistant asphalt surface material prepared in this embodiment consists of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 50%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound, and exchange catalyst. The content of styrene-butadiene-styrene thermoplastic elastomer is 4% of the mass of the base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 4% of the mass of the base asphalt, the content of reactive compatibilizer is 0.8% of the mass of the base asphalt, the content of zinc-based coordination aid is 1.5% of the mass of the ionomer in this embodiment, the content of polyhydroxy compound is 15% of the mass of the reactive compatibilizer in this embodiment, and the content of exchange catalyst is 0.2% of the mass of the polyhydroxy compound in this embodiment. The material in this embodiment has an elastomer-ionomer dual-network modified structure. At 25°C, with a weight of 100g and a 5s timeframe, it exhibits a penetration of 42, a softening point of 82°C using the ring and ball method, and a ductility of 32cm at 15°C. Furthermore, in a -12°C bending beam rheometer test, the material shows a stiffness modulus of 295MPa over 60s and a creep rate of 0.31; in a 64°C dynamic shear rheological test, the composite modulus G* is 4.8kPa; and in a 25°C fatigue test, the fatigue life is 1.1×10⁻⁶. 6 The elastic recovery rate is 76%. The crack-resistant asphalt pavement material of this embodiment is used to prepare crack-resistant road pavement, with a pavement Marshall stability of 10.5kN, a low-temperature bending failure strain of 2600με, and a high-temperature rutting dynamic stability of 4200 cycles / mm.

[0054] This embodiment focuses on optimizing high-temperature rutting resistance by using a higher reaction temperature and a high-neutralization degree ionomer to strengthen the ion-association network structure, significantly improving the high-temperature stability and stiffness of the material, making it suitable for high-temperature application scenarios such as hot regions, heavy-duty traffic roads, and highways.

[0055] Example 4:

[0056] A method for preparing a crack-resistant asphalt surface material, the entire process is carried out under nitrogen protection, including the following steps: S1 Base asphalt pretreatment: The base asphalt is heated to 163℃, and styrene-butadiene-styrene thermoplastic elastomer is added for high-shear dispersion for 33 min; S2 Modifier dispersion: An ionomer of ethylene-methacrylic acid copolymer with a neutralization degree of 48% and a zinc-based coordination aid are added, and the dispersion reaction is carried out at a controlled reaction temperature of 172℃ for 22 min; S3 Compatibilizer grafting: A reactive compatibilizer is added for grafting reaction for 18 min, followed by the addition of a polyhydroxy compound, and uniform dispersion is carried out at 168℃ for 17 min; S4 Crosslinking reaction: An exchange catalyst is added, and a low-shear reaction is carried out at 172℃ for 45 min to form a crosslinked network structure; S5 Curing and discharge: The material is discharged after curing at 168℃ for 45 min. In step S1, the high-shear dispersion speed is 7500 rpm, the system water content is 0.06%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 4.3% of the mass of the base asphalt. In step S2, the amount of ethylene-methacrylic acid copolymer ionomer added in this embodiment is 3.5% of the mass of the base asphalt, the zinc-based coordination aid in this embodiment is zinc acetate, and the amount added is 1.3% of the mass of the ionomer in this embodiment, and the dispersion speed is 3500 rpm. In step S3, the reactive compatibilizer in this embodiment is maleic anhydride-grafted polyethylene, and the amount added is 1.3% of the mass of the base asphalt; the polyhydroxy compound in this embodiment is pentaerythritol, and the amount added is 22% of the mass of the reactive compatibilizer in this embodiment, and the stirring speed is 3500 rpm. In step S4, the reaction temperature is 172℃, the low-shear stirring rate is 150 rpm, the exchange catalyst in this embodiment is zinc acetate, and the amount added is 0.6% of the mass of the polyhydroxy compound in this embodiment. A closed reactor is used, the reactor has a temperature control system, and the discharge temperature is 159℃. The crack-resistant asphalt surface material prepared in this embodiment consists of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 48%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound, and exchange catalyst. The content of styrene-butadiene-styrene thermoplastic elastomer is 4.3% of the mass of base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 3.5% of the mass of base asphalt, the content of reactive compatibilizer is 1.3% of the mass of base asphalt, the content of zinc-based coordination aid is 1.3% of the mass of the ionomer in this embodiment, the content of polyhydroxy compound is 22% of the mass of the reactive compatibilizer in this embodiment, and the content of exchange catalyst is 0.6% of the mass of the polyhydroxy compound in this embodiment.The material in this embodiment has an elastomer-ionomer dual-network modified structure. Under conditions of 25℃, 100g, and 5s, the penetration is 46, the softening point by the ring and ball method is 80℃, and the ductility at 15℃ is 38cm. Furthermore, in the bending beam rheometer test at -12℃, the stiffness modulus at 60s is 265MPa, and the creep rate is 0.38. In the dynamic shear rheological test at 64℃, the composite modulus G* is 4.2kPa, and in the fatigue test at 25℃, the fatigue life is 1.3×10. 6 The elastic recovery rate is 80%. The crack-resistant asphalt pavement material of this embodiment is used to prepare crack-resistant road pavement, with a pavement Marshall stability of 9.8 kN, a low-temperature bending failure strain of 2900 με, and a high-temperature rutting dynamic stability of 3800 cycles / mm.

[0057] This embodiment adopts a comprehensive balanced parameter configuration. By finely adjusting the distribution ratio of each group, the optimal coordination of high and low temperature performance is achieved. Each parameter is close to the boundary of the process range but maintains safety. The material exhibits excellent comprehensive performance and is suitable for demanding application scenarios such as special engineering projects, urban expressways and high-grade road construction with extremely high requirements for the high and low temperature performance of materials.

[0058] Comparative Example 1: It is basically the same as Example 1, except that the heating temperature of the base asphalt in step S1 is 150°C, while other process parameters remain unchanged.

[0059] Comparative Example 2: It is basically the same as Example 1, except that in step S1, the amount of styrene-butadiene-styrene thermoplastic elastomer added is 3% of the mass of the base asphalt, while the other component ratios and process conditions remain unchanged.

[0060] Comparative Example 3: It is basically the same as Example 1, except that the high shear dispersion time in step S1 is 15 min, while other process parameters remain unchanged.

[0061] Comparative Example 4: It is basically the same as Example 1, except that the degree of neutralization of the ethylene-methacrylic acid copolymer ionomer in step S2 is 30%, while other components and process conditions remain unchanged.

[0062] Comparative Example 5: It is basically the same as Example 1, except that the reaction temperature in step S2 is 150°C, while other process parameters remain unchanged.

[0063] Comparative Example 6: It is basically the same as Example 1, except that no zinc-based coordination agent is added in step S2, only ethylene-methacrylic acid copolymer ionomer is added, and other components and process conditions remain unchanged.

[0064] Comparative Example 7: It is basically the same as Example 1, except that in step S3, no reactive compatibilizer is added, and a polyhydroxy compound is added directly. Other process steps and parameters remain unchanged.

[0065] Comparative Example 8: It is basically the same as Example 1, except that the compatibilizer grafting reaction time in step S3 is 5 min, while other process parameters remain unchanged.

[0066] Comparative Example 9: Basically the same as Example 1, except that the amount of polyhydroxy compound added in step S3 is 5% of the mass of the reactive compatibilizer, while the proportions of other components and process conditions remain unchanged.

[0067] Comparative Example 10: It is basically the same as Example 1, except that the crosslinking reaction temperature in step S4 is 155°C, while other process parameters remain unchanged.

[0068] Comparative Example 11: It is basically the same as Example 1, except that no exchange catalyst is added in step S4, and the low-shear reaction is carried out directly. Other process steps and parameters remain unchanged.

[0069] Comparative Example 12: Basically the same as Example 1, except that the low shear reaction time in step S4 is 15 min, while other process parameters remain unchanged.

[0070] Comparative Example 13: It is basically the same as Example 1, except that the curing temperature in step S5 is 140°C, while other process parameters remain unchanged.

[0071] Comparative Example 14: Basically the same as Example 1, except that the entire preparation process was carried out in an air atmosphere without nitrogen protection, and other components and process conditions remained unchanged.

[0072] Performance testing:

[0073] Bending beam rheological test: The test object is a rectangular beam specimen prepared from crack-resistant asphalt pavement material. The purpose of the test is to evaluate the crack resistance and stress relaxation characteristics of the material under low temperature conditions. The test principle is based on the change law of stiffness modulus and creep rate of the material under three-point bending loading mode. The experimental method uses a bending beam rheometer. The specimen with dimensions of 125mm×12.5mm×6.25mm is subjected to constant load creep test at -12℃±0.1℃. After applying a constant load for 240 seconds, the deflection change at the midpoint of the specimen is measured. The standard is based on ASTM D6648-08. Key parameters include test temperature -12℃±0.1℃, loading time 240s, load magnitude determined according to the estimated modulus of the specimen, and specimen span ratio 8:1. Data processing calculates the stiffness modulus S(60) and creep rate m value at 60 seconds.

[0074] Dynamic shear rheological test: The test object is crack-resistant asphalt pavement material. The purpose of the test is to evaluate the viscoelastic properties and resistance to permanent deformation of the material under different temperature and frequency conditions. The test principle is based on the determination of the complex modulus and phase angle of the material under oscillating shear mode. The experimental method uses a dynamic shear rheometer with a parallel plate geometry. The sample thickness is 1 mm and the diameter is 25 mm. Strain control testing is carried out at 10 rad / s at 64℃. The strain level is determined by a pre-defined linear viscoelastic range. The complex shear modulus G and phase angle δ are measured. The standard is ASTM D7175-15, "Standard Test Method for Determination of Rheological Properties of Asphalt Binders Using Dynamic Shear Rheometer". Key parameters are: test temperature 64℃±0.1℃, oscillation frequency 10 rad / s±0.1 rad / s, strain level within the linear viscoelastic range, and parallel plate gap 1.0 mm±0.005 mm. Data processing calculates the complex modulus G and phase angle δ. The evaluation parameter G* / sinδ is used to characterize rutting resistance.

[0075] Fatigue performance testing experiment: The test object is crack-resistant asphalt pavement material. The purpose of the test is to evaluate the fatigue life and damage accumulation characteristics of the material under repeated loading. The test principle is based on the material stiffness modulus decay law under strain control mode to determine fatigue life. The experimental method uses a dynamic shear rheometer to perform sinusoidal strain scanning at 25℃. The initial strain amplitude is 2.5%, the frequency is 10Hz, and continuous loading is performed until the complex modulus drops to 50% of the initial value. The standard is AASHTO T321-17. Key parameters include test temperature 25℃±0.1℃, loading frequency 10Hz±0.1Hz, strain amplitude 2.5%±0.1%, and the failure criterion is the number of cycles when G* drops to 50% of the initial value. Data processing and statistics: the number of cycles when the failure criterion is reached is taken as the fatigue life Nf, and the fatigue equation Nf=A(1 / γ)^B is established.

[0076] Rotating Thin Film Oven Test: The test subject is crack-resistant asphalt surface material. The purpose of the test is to simulate the short-term aging behavior of asphalt during hot-mix processing and evaluate its resistance to thermo-oxidative aging. The test principle is based on the degree of thermo-oxidative reaction of the material under controlled temperature and airflow conditions. Experimental Method: 35g samples are placed in a standard glass bottle and rotated at 15rpm for 85 minutes in an oven at 163℃±1℃, with an airflow of 4000mL / min. After the test, the mass loss and changes in residual properties are measured. The standard is based on ASTM D2872-12. Key parameters are: test temperature 163℃±1℃, rotation speed 15rpm±1rpm, airflow 4000mL / min±200mL / min, and test time 85min±1min. Data Processing: Indicators such as mass change rate, softening point increment, penetration ratio, and ductility retention rate are calculated to evaluate the degree of aging.

[0077] Marshall stability test: The test object is an asphalt mixture specimen containing crack-resistant asphalt pavement material. The purpose of the test is to evaluate the deformation resistance and load-bearing strength of the mixture. The test principle is based on the maximum failure load and corresponding deformation of the specimen under standard conditions. The experimental method uses a Marshall testing apparatus. Cylindrical specimens with a diameter of 101.6 mm and a height of 63.5 mm are prepared. After being kept in a 60℃ water bath for 30-40 minutes, a loading test is performed at a rate of 50 mm / min until failure. The standard is ASTM D6927-15, "Standard Test Method for Design of Marshall Asphalt Mixtures". Key parameters are: specimen holding temperature 60℃±1℃, holding time 30-40 min, loading rate 50 mm / min±2 mm / min, and specimen porosity 4%±0.5%. Data processing: The maximum load is recorded as the Marshall stability (MS), and the deformation at the maximum load is recorded as the flow value (FL). This is combined with rutting tests and rheological parameters for analysis.

[0078] Differential Scanning Calorimetry (DSC): The test subject was a crack-resistant asphalt pavement material. The purpose of the test was to determine the glass transition temperature, phase transition characteristics, and heat capacity change of the material, to verify the crosslinking and compatibility effects. The test principle is based on the relationship between heat flow and temperature during programmed temperature rise. The experimental method used a differential scanning calorimeter. 5-10 mg of sample was placed in an aluminum crucible and heated from -80°C to 200°C at a rate of 10°C / min under nitrogen protection. The heat flow-temperature curve was recorded. The standard was ASTM D3418-15, "Standard Test Method for Determination of Glass Transition Temperature of Polymers," with key parameters including a heating rate of 10°C / min ± 0.5°C / min, nitrogen flow rate of 50 mL / min ± 5 mL / min, sample mass of 5-10 mg, and temperature range of -80°C to 200°C. Data processing determined the glass transition temperature (Tg), possible phase transition peak temperatures, and specific heat capacity changes through the heat flow curves, and analyzed the thermodynamic characterization of the elastomer-ionomer network structure.

[0079] The surface material properties of the embodiments and comparative examples are summarized in Table 1. The embodiments of the present invention show significant advantages over the comparative examples in all key performance indicators: the S(60) stiffness modulus of embodiments 1-4 is controlled within the ideal range of 250-295 MPa, significantly lower than the 285-380 MPa of most comparative examples, proving superior low-temperature crack resistance; at the same time, the m value of the embodiments remains at a high level of 0.31-0.42, significantly better than the 0.22-0.34 range of the comparative examples, indicating stronger stress relaxation ability; in terms of high-temperature performance, the complex modulus G* of the embodiments reaches 2.2-4.8 kPa, generally higher than the 2.1-3.4 kPa of the comparative examples, and the fatigue life reaches 1.1-1.5 × 10⁻⁶ kPa. 6 This is significantly higher than the comparative example of 0.5-1.1×10⁻⁶.6 Furthermore, the results demonstrate excellent resistance to rutting and fatigue. In terms of Marshall stability, the examples achieved 8.5-10.5 kN, significantly better than the comparative examples' 6.5-9.0 kN. Particularly noteworthy is the RTFOT mass change rate, which was only 0.12-0.18% in the examples, significantly lower than the comparative examples' 0.17-0.35%, demonstrating excellent anti-aging performance. The glass transition temperature (Tg) of the examples was within a reasonable range of -18.5 to -12.8 °C, reflecting the optimized effect of the dual-network structure. In contrast, the comparative examples, lacking key components or with deviated process parameters, showed significantly deteriorated performance. This fully verifies the necessity and synergistic effect of each component and process step in the present invention, proving that the elastomer-ionomer dual-network modification technology can effectively balance low-temperature crack resistance and high-temperature rutting resistance, while also possessing excellent fatigue durability and anti-aging stability.

[0080] Table 1 Summary of Basic Physical Performance Test Results for Examples and Comparative Examples

[0081]

[0082]

[0083] pass Figures 1 to 4 The experimental data analysis clearly demonstrates that the technical solution of this invention has significant reliability and effectiveness. From... Figure 1 It can be seen that (basic conditions: ionomer neutralization degree 45%, S4 crosslinking reaction temperature 170℃, exchange catalyst content 0.5%), when the SBS content is in the range of 4.0%-5.0%, the stiffness modulus of S(60) shows a stable decreasing trend, while the Marshall stability increases simultaneously, reaching the optimal balance point at 4.5%, proving that this ratio can effectively improve the low-temperature flexibility while improving the mechanical strength of the mixture; Figure 2 The results show that (basic conditions: SBS content 4.5%, S4 crosslinking reaction temperature 170℃, exchange catalyst content 0.5%) the neutralization degree of ionomers has a significant impact on material properties in the range of 40%-50%, especially at 45%, the stiffness modulus and Marshall stability of S(60) reach the optimal combination, indicating that the ion-associated network forms the best structure under this neutralization degree. Figure 3 The effects of crosslinking reaction temperature on complex modulus G and fatigue life (under the following conditions: SBS content 4.5%, ionomer neutralization degree 45%, exchange catalyst content 0.5%) showed a clear parabolic relationship. Both indicators reached their peak values ​​at 170℃, confirming that the activation energy of crosslinking reaction and thermal degradation reached the optimal balance at this temperature. Figure 4The results (under the following conditions: SBS content 4.5%, ionomer neutralization degree 45%, S4 crosslinking reaction temperature 170℃) show that the catalyst content in the range of 0.2%-0.8% has an effect on material properties that first increases and then decreases. At 0.6%, both the complex modulus G and fatigue life reach their optimal values, proving that this ratio can achieve the best balance between catalytic efficiency and selectivity. The above four sets of experimental data corroborate each other, forming a complete technical proof system, fully verifying the scientific rationality of the design of each key parameter of the present invention, and ensuring that the modified asphalt mixture has excellent mechanical properties and durability in practical applications.

[0084] Figure 5 The figure shows the evolution of the transmission FTIR spectrum in each stage from S1 to S5 of Example 2 of the present invention. The results systematically demonstrate the rationality, reliability and effectiveness of the proposed scheme: First, after introducing E-MAA with a neutralization degree of about 40% and a zinc source in S2, the spectrum at 1545±5cm -1 1415±5cm -1 The presence of typical COO- asymmetric / symmetric stretching absorption and stable splitting, with Δν = νas - νs located within the reasonable range of the ion cluster, indicates that the carboxylate forms an effective coordination network with Zn; secondly, after the addition of PE-g-MA and glycerol to S3, the 1850 / 1780 cm⁻¹... -1 anhydride ring bimodal and 3200-3600cm -1 The broad OH band was significantly enhanced, accurately reflecting the presence of the reaction precursor; further, during the S4 catalytic crosslinking stage, the bimodal peaks of the anhydride ring significantly decreased, with a peak length of 1730-1745 cm⁻¹. -1 Ester C=O and 1160-1240cm -1 The COC peak simultaneously strengthens while the OH band weakens accordingly. The difference spectrum (S4-S3) shows a positive ester peak and a negative anhydride peak. The esterification index (Iester) increases while the anhydride index (IMA) decreases. Quantitatively, this is consistent with the expected esterification / exchange reaction pathway, proving that the reactive compatibilizer and polyol form a stable ester bond anchor and exchangeable network under the action of Sn(Oct)2. Simultaneously, characteristic SBS peaks (such as 965 and 910 cm⁻¹) are observed. -1 Under nitrogen protection and controlled temperature, the structure remained largely stable with only slight thermal history effects, indicating that the elastomer is still dominated by a physical network, thus working in conjunction with the ionomer coordination network and ester bond network. Finally, after S5 ripening, the peak shapes and intensities stabilized, and the ratio of salt peak splitting to ester peaks remained consistent, indicating that the network structure had reached a chemical and phase steady state within the process window. Therefore... Figure 5 The FTIR evidence chain presented fully supports the dual-network modification construction of "ionomer coordination cluster + esterification / exchange anchor + SBS physical phase" in Example 2, proving that the preparation scheme is chemically self-consistent, experimentally verifiable, and has predictable low-temperature crack resistance and durability gains in engineering applications.

[0085] Figure 6 The comparison of S(60) stiffness modulus and Marshall stability between the embodiments and comparative examples of the present invention shows that while maintaining a low S(60) stiffness modulus (250-295MPa) to ensure excellent low-temperature crack resistance, the Marshall stability of the embodiments is significantly improved to 8.5-10.5kN. Although the stability of some samples in the comparative examples is similar, the S(60) stiffness modulus is generally higher (285-380MPa), indicating that the embodiments achieve the best balance between low-temperature flexibility and mechanical strength. Figure 7 For the comparison of complex modulus and fatigue life between embodiments and comparative examples of the present invention, the embodiments show G values ​​of 2.2-4.8 kPa and fatigue lives of 1.1-1.5 × 10⁻⁶ kPa. 6 This superior combination, compared to the comparative example with a G-value of 2.1-3.4 kPa and a fatigue life of 0.5-1.1 × 10⁻⁶ kPa, demonstrates superior performance. 6 Furthermore, the embodiment demonstrates superior performance in both high-temperature viscoelastic properties and fatigue crack resistance. Figure 8 For the comparison of the m-values ​​and glass transition temperatures of the embodiments and comparative examples of the present invention, the m-value range of 0.31-0.42 in the embodiments forms an ideal match with the Tg range of -18.5 to -12.8℃, indicating that the elastomer-ionomer dual network structure effectively improves the low-temperature stress relaxation characteristics, while the combination of the m-value of 0.22-0.34 in the comparative examples with the Tg range of -23.8 to -15.0℃ shows poor low-temperature performance coordination; Figure 9 For the comparison of the mass change rate of RTFOT in the embodiments and comparative examples of the present invention, the mass change rate of the embodiments is controlled at an excellent level of 0.12-0.18%, which is significantly lower than the range of 0.17-0.35% of the comparative examples. This fully demonstrates the significant improvement effect of the cross-linked network structure on the resistance to thermo-oxidative aging. The comprehensive comparative analysis of the four key performance indicators shows that the embodiments of the present invention exhibit significantly better comprehensive performance advantages than the comparative examples in multiple dimensions such as low temperature crack resistance, high temperature stability, fatigue durability and anti-aging, verifying the excellent effectiveness of the elastomer-ionomer dual network modification technology.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any equivalent structural transformations made under the concept of the present invention and using the contents of the specification and drawings of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a crack-resistant asphalt surface material, characterized in that, The entire process is carried out under nitrogen protection and includes the following steps: S1 Base Asphalt Pretreatment: Heat the base asphalt to 160-165℃, add styrene-butadiene-styrene thermoplastic elastomer and disperse under high shear for 30-35 minutes; S2 Modifier Dispersion: Add ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40-50% and zinc-based coordination agent, and disperse the reaction at a temperature of 160-175℃ for 20-30 minutes. S3 Compatibilizer Grafting: Add a reactive compatibilizer and carry out the grafting reaction for 15-25 min, then continue to add a polyhydroxy compound and disperse it evenly at 160-170℃ for 15-20 min; S4 Crosslinking Reaction: Add an exchange catalyst and carry out a low-shear reaction at 165-175℃ for 35-50 min to form a crosslinked network structure; S5 maturation and discharge: discharge after maturation at 155-172℃ for 35-50 minutes; The reactive compatibilizer mentioned in step S3 is at least one of maleic anhydride-grafted polypropylene or maleic anhydride-grafted polyethylene, and the amount added is 0.8-1.5% of the mass of the base asphalt; The polyhydroxy compound is at least one of pentaerythritol, citric acid or glycerol, and the amount added is 15-25% of the mass of the reactive compatibilizer, and the stirring speed is 2000-4000 rpm. In step S4, the reaction temperature is 169-172℃, the low-shear stirring rate is 120-160 rpm, and the exchange catalyst is at least one of zinc acetate, stannous octoate, or tetrabutyl titanate, with an addition amount of 0.2-0.8% of the mass of the polyhydroxy compound.

2. The method for preparing a crack-resistant asphalt surface material as described in claim 1, characterized in that, In step S1, the high-shear dispersion speed is 6000-8000 rpm, the water content of the system is less than 0.1%, and the amount of styrene-butadiene-styrene thermoplastic elastomer added is 4-5% of the mass of the base asphalt.

3. The method for preparing a crack-resistant asphalt surface material as described in claim 1, characterized in that, In step S2, the amount of ethylene-methacrylic acid copolymer ionomer added is 2.5-4% of the mass of the base asphalt, and the zinc-based coordination aid is at least one of zinc oxide, zinc acetate, zinc stearate or zinc naphthenate, and the amount added is 0.8-1.5% of the mass of the ionomer, and the dispersion speed is 2000-4000 rpm.

4. The method for preparing a crack-resistant asphalt surface material as described in claim 1, characterized in that, A closed reactor is used, which has a temperature control system and the discharge temperature is 155-160℃.

5. A crack-resistant asphalt surface material, characterized in that, The crack-resistant asphalt surface material is prepared by the preparation method described in any one of claims 1 to 4. The material is composed of base asphalt, styrene-butadiene-styrene thermoplastic elastomer, ethylene-methacrylic acid copolymer ionomer with a neutralization degree of 40-50%, zinc-based coordination aid, reactive compatibilizer, polyhydroxy compound and exchange catalyst.

6. The crack-resistant asphalt surface material as described in claim 5, characterized in that, The content of styrene-butadiene-styrene thermoplastic elastomer is 4-5% of the mass of the base asphalt, the content of ethylene-methacrylic acid copolymer ionomer is 2.5-4% of the mass of the base asphalt, the content of reactive compatibilizer is 0.8-1.5% of the mass of the base asphalt, the content of zinc-based coordination aid is 0.8-1.5% of the mass of the ionomer, the content of polyhydroxy compound is 15-25% of the mass of the reactive compatibilizer, and the content of exchange catalyst is 0.2-0.8% of the mass of the polyhydroxy compound.

7. The crack-resistant asphalt surface material as described in claim 5, characterized in that, The material has an elastomer-ionomer dual-network modified structure. Under the conditions of 25℃, 100 g, and 5 s, the penetration is 40-60 (0.1 mm), the softening point of the ring and ball method is ≥75℃, the ductility at 15℃ is ≥30 cm, and the stiffness modulus of the material in the bending beam rheometer test at -12℃ is less than or equal to 300 MPa at 60 s and the creep rate is ≥0.

30. The composite modulus G* was 2.0-5.0 kPa in the dynamic shear rheological test at 64℃, and the fatigue life was ≥10 kPa in the fatigue test at 25℃. 6 The elastic recovery rate is ≥75%.

8. The use of a crack-resistant asphalt pavement material prepared by the preparation method according to any one of claims 1 to 4, or the crack-resistant asphalt pavement material according to any one of claims 5 to 7, in the preparation of road pavement, characterized in that, This material is used to prepare crack-resistant road surface layers with a road surface Marshall stability ≥8kN, low-temperature bending failure strain ≥2500με, and high-temperature rutting dynamic stability ≥3000 cycles / mm.

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