Temperature-control phase-change asphalt mixture for pavement and preparation method of temperature-control phase-change asphalt mixture

Abstract

The invention relates to a temperature-control phase-change asphalt mixture for pavements and a preparation method thereof, and the temperature-control phase-change asphalt mixture comprises the following raw materials in percentage by weight: 80wt%-85wt% of aggregate, 7wt%-9wt% of mineral powder, 6.0 wt%-6.8 wt% of SBS modified asphalt, 0.3 wt%-0.5 wt% of a fiber stabilizer and 1.0 wt%-1.5 wt% of a microstructure phase-change material, wherein the fiber stabilizer is formed by compounding surface modified aramid fiber and activated lignin fiber. According to the temperature-control phase-change asphalt mixture for the pavement, the surface-modified aramid fibers and the activated lignin fibers are compounded, so that the cost is reduced, the defect of insufficient adhesiveness of the aramid fibers is overcome, the effect of inhibiting crack propagation is maintained, and meanwhile, the water damage resistance is improved; the microstructure phase change material absorbs heat in a phase change manner to inhibit high-temperature softening and releases heat to delay low-temperature cracking, adsorbs a polymer to coat the wax core to prevent leakage, and improves the compatibility with asphalt, so that the asphalt mixture has high-temperature rut resistance, low-temperature crack resistance and stable phase change circulation, and has water damage resistance and durability.

Description

Technical Field

[0001] This invention belongs to the field of asphalt pavement materials technology, specifically relating to a temperature-controlled phase change asphalt mixture for pavement and its preparation method. Background Technology

[0002] As a temperature-sensitive material, asphalt mixtures are susceptible to environmental temperature changes due to their viscoelastic properties. Temperature variations cause a series of damages to asphalt pavements. Extreme heat can cause excessive softening of the asphalt, leading to rutting and deformation, while low temperatures can cause cracking, affecting the long-term performance of the asphalt pavement. Therefore, employing appropriate temperature regulation methods to better maintain the structural stability of asphalt pavements during temperature changes can avoid frequent maintenance and resurfacing due to high and low temperature damage, thus improving pavement durability.

[0003] While existing phase change materials (PCMs) can regulate the temperature of asphalt pavements through the latent heat of phase change, several technical bottlenecks remain in practical applications. Specifically, the preparation process of current PCMs is complex, making it difficult to achieve ideal temperature regulation. Furthermore, these materials exhibit poor stability during repeated use, hindering their sustained temperature-regulating effect. Among various PCMs, organic solid-liquid PCMs have become a research focus due to their high latent heat of phase change, small volume change during phase change, and absence of phase separation. However, these materials also have significant drawbacks in practical applications: they are prone to leakage during phase change, which not only damages the asphalt cement structure and reduces strength but also delays temperature response and reduces temperature regulation efficiency. Existing technologies attempt to prevent leakage by encapsulating organic solid-liquid PCMs, but the encapsulation materials often have poor compatibility with asphalt, leading to asphalt segregation and viscoelasticity deterioration. Phase change material microcapsules, where the core material is encapsulated within microspheres by a wall material, resulting in complete core material coverage, suffer from an expensive encapsulation process that can interfere with the efficiency of the core material. These technical limitations directly lead to poor temperature regulation performance of asphalt pavements, hindering the effective extension of their service life. Therefore, there is an urgent need to develop a specialized asphalt mixture for pavements to overcome existing technological limitations and significantly improve the high-temperature rutting resistance, low-temperature crack resistance, freeze-thaw resistance, and durability of asphalt pavements. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a temperature-controlled phase change asphalt mixture for road surfaces and its preparation method. This asphalt mixture achieves high-temperature rutting resistance, low-temperature crack resistance, stable phase change cycle, and has water damage resistance and durability.

[0005] This invention is achieved through the following technical solution: On one hand, a temperature-controlled phase change asphalt mixture for road surface is provided, the raw materials of which, by weight percentage, include 80wt%-85wt% aggregate, 7wt%-9wt% mineral powder, 6.0wt%-6.8wt% SBS modified asphalt, 0.3wt%-0.5wt% fiber stabilizer, and 1.0wt%-1.5wt% microstructured phase change material;

[0006] The fiber stabilizer is composed of surface-modified aramid fibers and activated lignin fibers.

[0007] By combining surface-modified aramid fibers with activated lignin fibers, costs are reduced while compensating for the insufficient adhesion of aramid fibers and maintaining crack resistance and toughening effects. The aramid fibers form a three-dimensional network reinforcement structure, improving the tensile strength of the mixture and inhibiting asphalt dripping. The modified groups on their surface bond with the polar groups in SBS-modified asphalt and the polar groups of the adsorbed polymers in the phase change material, forming hydrogen bonds or ionic bonds, increasing interfacial shear strength and inhibiting crack propagation. The hydroxyl groups of the activated lignin fibers combine with the phase change material to form a composite adsorption network, enhancing the fixation ability of free asphalt, adsorbing free asphalt, increasing the viscosity of the mastic, filling micropores, reducing the porosity of the mixture, and thus improving the water loss resistance of the mixture.

[0008] The fiber stabilizer, which combines surface-modified aramid fiber and activated lignin fiber, produces a synergistic effect. Its high-temperature rutting resistance and low-temperature crack resistance are superior to those of single fiber, enabling the mixture to achieve high-temperature stability, prevent rutting, and block water erosion.

[0009] When the mass ratio of surface-modified aramid fibers is too low, the toughening effect is insufficient; when it is too high, clumping is likely. When the mass ratio of activated lignin fibers is too low, adsorption is insufficient; when it is too high, the mixture becomes too sticky. Specifically, the mass ratio of surface-modified aramid fibers to activated lignin fibers is 1:1 to 1:3. Preferably, the mass ratio of surface-modified aramid fibers to activated lignin fibers is 1:1.86.

[0010] Preferably, the surface-modified aramid fiber is obtained by uniformly spraying a 1.5% KH-792 silane coupling agent ethanol solution and curing it at 60°C for 30 minutes to achieve surface grafting of -NH2 groups; the activated lignin fiber is formed by impregnating dried lignin fiber in an ethanol-based solution containing 0.5% oleophilic nano-SiO2 and 0.1% OP-10 dispersant, ultrasonically treating it for 10 minutes, drying it at 80°C for 30 minutes, and then sieving it to form nano-coated fiber.

[0011] Microstructured phase change materials exhibit endothermic phase change that inhibits high-temperature softening and exothermic phase change that delays low-temperature cracking. Their adsorbed polymer-coated wax cores prevent leakage. The styrene segment of SBS-modified asphalt and the adsorbed polymer are entangled by van der Waals forces to form composite micelles, preventing phase separation of the phase change material, improving compatibility with asphalt, and ensuring stable phase change cycling. Furthermore, the butadiene segment and the wax core synergistically enhance low-temperature ductility.

[0012] Preferably, the microstructured phase change material comprises a wax core A and an adsorbed polymer B; the wax core A comprises paraffin and non-paraffin components.

[0013] The general formula for paraffin wax is: C n H 2n+2 n = 13 - 22 (paraffin defined by n = 13 is called C) 13 Linear alkane wax, C 13 The melting point of wax is -5.4℃, C 22 The melting point of the wax is 44℃; the non-paraffin components are selected from one or more of animal wax, plant wax, mineral wax, and synthetic wax.

[0014] Preferably, the adsorbent polymer B is selected from one or more of polyvinyl alcohol, cellulose ether, polyethylene oxide, polyvinylpyrrolidone, sodium alginate, and gelatin.

[0015] One reason for the stability of microstructured phase change materials is the steric hindrance effect; the adsorbed polymer is fixed on the outer surface of the wax particles, preventing adjacent wax particles from fusing. Another reason is electrostatic repulsion; wax particles containing acid or ester groups are first saponified with alkali, transforming into negatively charged carboxylic acid groups. The negative charges on adjacent wax particles create repulsive forces between the particles. The adsorbed polymer protects the wax core, adhering to it in a mesh-like structure. Even if the wax changes from a solid to a liquid state, the liquefied wax will not seep out between the polymer chains or polymer clusters. The microstructure is not a physical encapsulation, but in practice, it is encapsulated.

[0016] Preferably, the aggregate is selected from one or two types of basalt and granite.

[0017] Preferably, the mineral powder is limestone powder.

[0018] On the other hand, the present invention provides a method for preparing a temperature-controlled phase change asphalt mixture for road surfaces, comprising the following steps:

[0019] 1) Weigh the raw materials according to the above proportions;

[0020] 2) Put the aggregate into the mixing pot and heat it to 185-190℃, dry mixing time is 5s;

[0021] 3) Add surface-modified aramid fibers and mix for 15 seconds until the fibers are evenly dispersed, then add activated lignin fibers and mix for 10 seconds;

[0022] 4) Premix the mineral powder with the microstructured phase change material, add it to the mixing pot, and mix for no less than 10 seconds;

[0023] 5) Inject the preheated SBS modified asphalt to 165–170℃ into the mixing pot and mix for ≥45 seconds.

[0024] 6) Control the discharge temperature to 170℃-175℃, and you will get the desired result.

[0025] Preferably, the discharged mixture is stored in a storage silo at 160℃–170℃ for no more than 2 hours, and / or transported to the construction site within 30 minutes using a covered and insulated transport vehicle.

[0026] Beneficial effects

[0027] 1. The temperature-controlled phase change asphalt mixture for road surfaces proposed in this invention reduces costs by combining surface-modified aramid fibers with activated lignin fibers, compensates for the insufficient adhesion of aramid fibers while maintaining the effect of inhibiting crack propagation, and improves water loss resistance. The synergistic effect of the combination of the two improves the high-temperature rutting resistance and low-temperature crack resistance of the asphalt mixture.

[0028] 2. The microstructured phase change material of the present invention has the following properties: phase change endothermic inhibition of high-temperature softening, exothermic delay of low-temperature cracking, and its adsorbed polymer coating of wax core prevents leakage. The styrene segment of SBS modified asphalt and the adsorbed polymer are entangled by van der Waals forces to form composite micelles, which prevent phase separation of the phase change material, improve compatibility with asphalt, stabilize phase change cycle, and its butadiene segment and wax core synergistically improve low-temperature ductility.

[0029] 3. The asphalt mixture of the present invention achieves high-temperature resistance to rutting, low-temperature resistance to cracking, stable phase change cycle, and has resistance to water loss and durability. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the present invention, the accompanying drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0031] Figure 1 The diagram shows a schematic representation of the microstructured phase change material in a temperature-controlled phase change asphalt mixture for road surfaces, as proposed in an embodiment of the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0033] The following detailed explanation illustrates the specific implementation methods:

[0034] A temperature-controlled phase change asphalt mixture for road surfaces and its preparation method are disclosed below:

[0035] The raw materials for temperature-controlled phase change asphalt mixtures used in road surfaces include aggregates, mineral powder, SBS modified asphalt, fiber stabilizers, and microstructured phase change materials. The percentages of each raw material are as follows:

[0036] 80wt%-85wt% aggregate, 7wt%-9wt% mineral powder, 6.0wt%-6.8wt% SBS modified asphalt, 0.3wt%-0.5wt% fiber stabilizer, 1.0wt%-1.5wt% microstructured phase change material;

[0037] The aggregates used are one or both of basalt and granite, and the composite gradation of the aggregates satisfies the gradation curve. The cumulative passing rate of the aggregates on the standard sieve (mm) is shown in the table below:

[0038] sieve aperture size 16.0 9.5 4.75 2.36 1.18 0.6 0.3 0.15 0.075 Pass rate % 95-100 70-85 45-60 30-45 20-35 14-28 10-22 7-16 4-8

[0039] The mineral powder used is limestone powder with a median particle size (D50) of 10-25 μm and a specific surface area of ​​350-550 m². 2 / kg, asphalt adsorption value ≥1.20ml / 20g, moisture content ≤0.5wt%;

[0040] The SBS modified asphalt used is composed of base asphalt and SBS modifier. The amount of SBS modifier added is 3.5 to 5.0 wt% of the asphalt mass. The SBS type is star-shaped or linear styrene-butadiene block copolymer with a styrene content of 28 to 35%. The base asphalt grade is 70# or 90# road petroleum asphalt. After 48 hours of segregation, the difference in softening point between the upper and lower layers of the SBS modified asphalt is ≤2.5℃, and the low temperature phase of glass transition (butadiene segment) is -85 to 100℃.

[0041] The fiber stabilizer used is a composite of surface-modified aramid fibers and activated lignin fibers. The aramid fibers have a length of 6-12 mm, preferably 9 mm, and are treated with KH-792 silane coupling agent, with a grafting rate ≥1.5 wt%. The lignin fibers have a length of 3-5 mm and a specific surface area of ​​2.5-4.0 m². 2 / g, dried lignin fibers are impregnated in an ethanol-based solution containing 0.5% oleophilic nano-SiO2 and 0.1% OP-10 dispersant, ultrasonically treated for 10 minutes, dried at 80℃ for 30 minutes, and then sieved to form nano-coated fibers, which are activated lignin fibers.

[0042] The microstructured phase change material used comprises a wax core A and an adsorbent polymer B. It is a wax-based microstructured colloidal protective phase change material powder. The wax core is in a colloidal state under the protection of the adsorbent polymer (encapsulation material), such as polyvinyl alcohol. Wax core A includes paraffin and non-paraffin components. The operating temperature range of the microstructured phase change material is defined by the melting point of the wax core components. The general formula for paraffin is: C n H 2n+2 n = 13 - 22 (paraffin defined by n = 13 is called C) 13 Linear alkane wax, C 13 The melting point of wax is -5.4℃, C 22 The melting point of the wax is 44℃; the non-paraffin components are selected from one or more of animal wax, plant wax, mineral wax, and synthetic wax; the adsorbent polymer B is selected from one or more of polyvinyl alcohol, cellulose ether, polyethylene oxide, polyvinylpyrrolidone, sodium alginate, and gelatin.

[0043] The preparation process of microstructured phase change materials is as follows:

[0044] S1. Wax phase preparation: heating the phase change wax core to a molten state at 70-90℃;

[0045] S2. Aqueous phase preparation: Heat water to 75-85℃, add emulsifier, stabilizer, dispersant, and ion regulator in sequence, and adjust the pH to 8.5-10.0;

[0046] S3. Emulsification process: The molten wax phase and the aqueous phase are mixed at an oil-water mass ratio of 1:1, and sheared at 8000-12000 rpm for 5-15 minutes through a colloid mill to obtain an emulsion particle size D50 of 0.5-2.0 μm.

[0047] S4. Drying and powdering: Pump the emulsion into a centrifugal spray drying tower. Parameter control: inlet temperature 140-160℃, outlet temperature 65-80℃, atomizing disc speed 15000-20000rpm, to obtain microstructured phase change material powder with particle size distribution D50=10-40um.

[0048] A method for preparing temperature-controlled phase change asphalt mixture for road surfaces includes the following steps:

[0049] 1) Weigh the raw materials according to the above proportions;

[0050] 2) Use a twin-shaft forced mixing pot with a rotation speed of 45 rpm. Put the aggregate into the mixing pot and heat it to 185-190℃. Dry mix for 5 seconds. Spray in 0.1% viscosity reducer and continue dry mixing for 15 seconds to form a lubricating film on the surface of the aggregate.

[0051] 3) Add surface-modified aramid fibers, adjust the speed to 60 rpm and mix for 15 seconds until the fibers are evenly dispersed, then add activated lignin fibers, reduce the speed to 40 rpm and mix for 10 seconds until there are no lumps in the pot;

[0052] 4) Premix the mineral powder with the microstructured phase change material, cool the mixing pot to 175°C, add the premix in 3 batches, with an interval of 10 seconds between each batch, and the mixing cycle is no less than 10 seconds.

[0053] 5) Preheat the SBS modified asphalt to 165–170℃ in a constant temperature tank by circulating and stirring. Then spray it into the mixing pot through a high-pressure atomizing nozzle at a speed of 70 rpm and force mix for ≥45 seconds.

[0054] 6) Control the discharge temperature to 170℃-175℃, and you will get the desired result.

[0055] Before using temperature-controlled phase change asphalt mixtures for road surfaces, they need to be tested. The testing methods are as follows:

[0056] High-temperature rutting resistance test:

[0057] Specimen preparation: 300×300×50mm plate-shaped specimens were formed by roller rolling; Test conditions: temperature 70℃, roller pressure 0.7MPa, rolling speed 42 times / minute; Test process: pre-compacting for 2 minutes, formal test for 60 minutes, and rut depth was recorded every minute.

[0058] Low-temperature crack resistance test:

[0059] Specimen preparation: Cut a 250×30×35mm prism beam and keep it at -15℃ for 4 hours; Test conditions: Temperature -15℃, loading rate 50mm / min; Test process: Three-point bending load until failure, and record the load-displacement curve.

[0060] Water stability test:

[0061] S1. Two sets of cylindrical specimens, Group A: 25℃ water bath for 2h, splitting strength RT1 was measured; Group B: vacuum saturation → -18℃ freezing for 16h → 60℃ water bath for 24h → 25℃ water bath for 2h, splitting strength RT2 was measured.

[0062] S2. Result Calculation

[0063] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise stated, all percentages, ratios, proportions, or parts are by weight.

[0064] Unless otherwise specified, the reagents and raw materials used in the embodiments and comparative examples of this invention are commercially available.

[0065] Example 1

[0066] The specific steps for preparing temperature-controlled phase change asphalt mixture for road surfaces using the method of this invention are as follows:

[0067] Weigh out 85% aggregate, 7% mineral powder, 6.0% SBS modified asphalt, 0.5% fiber stabilizer, and 1.5% microstructured phase change material by mass ratio, with the mass ratio of surface-modified aramid fiber to activated lignin fiber being 1:1.86. Using a twin-shaft forced mixing pot at 45 rpm, add the aggregate to the pot and heat to 185°C, dry-mixing for 5 seconds. Inject a viscosity reducer and continue dry-mixing for 15 seconds to form a lubricating film on the aggregate surface. Add the surface-modified aramid fiber, adjust the speed to 60 rpm, and mix for 15 seconds until the fiber is evenly dispersed. Then add the activated lignin fiber, reduce the speed to 40 rpm, and mix for 10 seconds until no lumps remain in the pot. Premix the mineral powder and microstructured phase change material, cool the mixing pot to 175°C, and add the premix in three batches, with a 10-second interval between each batch, for a total mixing cycle of 10 seconds. SBS modified asphalt is preheated to 170°C in a constant-temperature tank by circulating stirring. It is then sprayed into the mixing pot through a high-pressure atomizing nozzle and forcibly mixed at 70 rpm for 45 seconds. The discharge temperature is controlled at 175°C to obtain the final product.

[0068] Example 2

[0069] Compared with Example 1, the proportion of raw materials weighed was changed, but the preparation method of asphalt mixture remained unchanged.

[0070] Weigh out 85% aggregate, 7% mineral powder, 6.2% SBS modified bitumen, 0.5% fiber stabilizer, and 1.3% microstructure phase change material by mass ratio, with the mass ratio of surface-modified aramid fiber to activated lignin fiber being 1:1.

[0071] Example 3

[0072] Compared with Example 1, the proportion of raw materials weighed was changed, but the preparation method of asphalt mixture remained unchanged.

[0073] Weigh out 85% aggregate, 7% mineral powder, 6.2% SBS modified bitumen, 0.5% fiber stabilizer, and 1.3% microstructure phase change material by mass ratio, with the mass ratio of surface-modified aramid fiber to activated lignin fiber being 1:3.

[0074] Example 4

[0075] Compared with Example 1, the proportion of raw materials weighed was changed, but the preparation method of asphalt mixture remained unchanged.

[0076] Weigh out 85% aggregate, 7% mineral powder, 6.2% SBS modified bitumen, 0.5% fiber stabilizer, and 1.3% microstructure phase change material by mass ratio, with the mass ratio of surface-modified aramid fiber to activated lignin fiber being 1:1.86.

[0077] Comparative Example 1

[0078] Compared with Example 4, no fiber stabilizer was added to the asphalt mixture, but the preparation method of the asphalt mixture remained unchanged.

[0079] Weigh out 85% aggregate, 7.5% mineral powder, 6.2% SBS modified asphalt, and 1.3% microstructured phase change material by mass ratio for later use.

[0080] Comparative Example 2

[0081] Compared with Example 4, no microstructured phase change material was added to the asphalt mixture, and the preparation method of the asphalt mixture remained unchanged.

[0082] Weigh out 85% aggregate, 8.3% mineral powder, 6.2% SBS modified bitumen, and 0.5% fiber stabilizer by mass ratio, with the mass ratio of surface-modified aramid fiber to activated lignin fiber being 1:1.86.

[0083] Comparative Example 3

[0084] Compared with Example 4, no microstructured phase change material and fiber stabilizer were added to the asphalt mixture, and the preparation method of the asphalt mixture remained unchanged.

[0085] Weigh out 85% aggregate, 8.3% mineral powder, and 6.2% SBS modified asphalt by mass ratio and set aside.

[0086] Effect Example

[0087] The asphalt mixtures obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were made into block samples, and then road performance tests were conducted on them. The results are shown in the table below.

[0088]

[0089] As can be seen from the data in the table above, the temperature-controlled phase change asphalt mixture for road surfaces prepared by the method of this invention exhibits superior high-temperature rutting resistance and low-temperature crack resistance compared to conventional mixtures. It also demonstrates stable phase change cycling and exhibits resistance to water loss and durability. The results show that samples from Examples 1 and 4 demonstrate the best high-temperature stability and low-temperature crack resistance, significantly outperforming Comparative Examples 1-3. Comparative Example 1 exhibits a low-temperature failure strain similar to that of Example 2, while Comparative Example 3 shows poor high-temperature stability and low-temperature crack resistance. Compared to Comparative Examples 1-3, Example 4 demonstrates improved resistance to water loss, resulting in asphalt mixtures with both water loss resistance and durability.

[0090] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A temperature-controlled phase change asphalt mixture for road surfaces, characterized in that, By weight percentage, its raw materials include 80wt%-85wt% aggregate, 7wt%-9wt% mineral powder, 6.0wt%-6.8wt% SBS modified bitumen, 0.3wt%-0.5wt% fiber stabilizer, and 1.0wt%-1.5wt% microstructured phase change material; The fiber stabilizer is composed of surface-modified aramid fibers and activated lignin fibers.

2. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 1, characterized in that, The mass ratio of the surface-modified aramid fiber to the activated lignin fiber is 1:1.

86.

3. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 2, characterized in that, The surface-modified aramid fiber is obtained by uniformly spraying a 1.5% KH-792 silane coupling agent ethanol solution and curing it at 60°C for 30 minutes to achieve surface grafting of -NH2 groups.

4. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 2, characterized in that, The activated lignin fiber is formed by impregnating dried lignin fiber in an ethanol-based solution containing 0.5% oleophilic nano-SiO2 and 0.1% OP-10 dispersant, followed by ultrasonic treatment for 10 minutes, drying at 80°C for 30 minutes, and sieving to form nano-coated fiber.

5. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 2, characterized in that, The microstructured phase change material comprises a wax core A and an adsorbed polymer B; the wax core A includes paraffin and non-paraffin components.

6. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 2, characterized in that, The adsorbent polymer B is selected from one or more of polyvinyl alcohol, cellulose ether, polyethylene oxide, polyvinylpyrrolidone, sodium alginate, and gelatin.

7. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 1, characterized in that, The aggregate is selected from one or two types of basalt and granite.

8. The temperature-controlled phase change asphalt mixture for road surfaces according to claim 1, characterized in that, The mineral powder is limestone powder.

9. A method for preparing a temperature-controlled phase change asphalt mixture for road surfaces according to any one of claims 1-8, characterized in that, Includes the following steps: 1) Weigh the raw materials according to the above proportions; 2) Put the aggregate into the mixing pot and heat it to 185-190℃, dry mixing time is 5s; 3) Add surface-modified aramid fibers and mix for 15 seconds until the fibers are evenly dispersed, then add activated lignin fibers and mix for 10 seconds; 4) Premix the mineral powder with the microstructured phase change material, add it to the mixing pot, and mix for no less than 10 seconds; 5) Inject the preheated SBS modified asphalt to 165–170℃ into the mixing pot and mix for ≥45 seconds. 6) Control the discharge temperature to 170℃-175℃, and you will get the desired result.

10. The method for preparing temperature-controlled phase change asphalt mixture for road surfaces according to claim 8, characterized in that, This also includes storing the discharged mixture in a storage silo at 160℃–170℃ for no more than 2 hours, and / or transporting it to the construction site within 30 minutes using a covered and insulated transport vehicle.

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