An environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions and its preparation method.

Abstract

This invention provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions and its preparation method, belonging to the field of road engineering materials technology. It comprises the following components in parts by weight: 30-50 parts of decommissioned wind turbine blade powder, 15-25 parts of SEBS-g-MAH, 10-25 parts of waste high-density PE, 5-10 parts of composite plasticizer, 2.5-3.5 parts of coupling agent, 0.5-1 part of antioxidant, and 0.1-0.5 parts of esterification catalyst. The decommissioned wind turbine blade powder is an epoxy resin-based glass fiber composite material with a particle size of 80-200 mesh and a glass fiber aspect ratio controlled at (5-8):1. This invention provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions and its preparation method, achieving simultaneous enhancement of high viscoelasticity and humid heat durability of asphalt in these regions, significantly improving the high-temperature rutting resistance, water damage resistance, and low-temperature crack resistance of asphalt, while simultaneously achieving the goals of solid waste resource utilization and low carbonization.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials technology, specifically to an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions and its preparation method. Background Technology

[0002] In hot and humid regions, such as Guangdong and Hainan, asphalt pavements face extreme service environments, primarily characterized by high temperatures, heavy rainfall, and drastic temperature fluctuations. Summer temperatures often reach 60-70℃, significantly reducing the viscoelasticity of asphalt and the dynamic shear modulus (G* / sinδ), leading to severe rutting with depths often exceeding 2.5mm. This high-temperature softening not only exacerbates pavement deformation but also increases traffic noise and tire wear, thus affecting the long-term service life of the pavement. Furthermore, annual rainfall exceeding 2000mm allows moisture to penetrate the asphalt-aggregate interface, causing bond failure and a freeze-thaw splitting strength ratio (TSR) below 80%, further shortening pavement life by more than 30%. Temperature fluctuations also lead to low-temperature cracking of asphalt, especially when diurnal temperature differences exceed 15℃, making asphalt prone to thermal shrinkage cracks, further exacerbating pavement damage and increasing repair costs.

[0003] Existing technologies typically modify asphalt to improve its performance. While SBS-modified asphalt exhibits good elastic recovery (approximately 75%), its poor compatibility with asphalt leads to phase separation after long-term use, particularly at high temperatures, making it difficult to effectively suppress rutting. Meanwhile, mineral filler reinforcement technology enhances asphalt's adhesion through physical filling, but lacks chemical bonding, making it prone to pavement stripping after moisture penetration. Furthermore, excessive use of mineral powder or calcium carbonate can cause embrittlement of the asphalt mixture, reducing splitting strength by approximately 20%. Although waste plastics (such as polyethylene) can improve asphalt's high-temperature deformation resistance, their non-polar surface and poor compatibility with asphalt result in segregation during construction, affecting pavement stability. Currently, traditional asphalt modification technologies face the challenge of balancing high viscoelasticity with wet-heat durability.

[0004] Chinese patent CN117843288A, entitled "A Method for Preparing Asphalt Mixture from Chemically Modified Decommissioned Wind Turbine Blade Material," discloses a method of first modifying crushed decommissioned wind turbine blades with a chemical modifier to obtain modified decommissioned wind turbine blade material; then, by compounding the modified decommissioned wind turbine blade material with asphalt mixture, a modified asphalt mixture is obtained, which can be directly used in highway construction. This technical solution improves the mechanical and physicochemical properties of the asphalt mixture, but it does not balance high viscoelasticity with wet heat durability.

[0005] Meanwhile, the recycling of decommissioned wind turbine blades (GFRP) is becoming an increasingly pressing issue in the global wind power industry. Decommissioned wind turbine blades are mainly composed of epoxy resin and glass fiber. The cross-linked network of epoxy resin has strong chemical inertness, making it difficult to degrade during recycling. Most recycling methods involve mechanical crushing, using it as low-value aggregate, but this method has very low added value, with a resource utilization rate of less than 10%. Furthermore, the surface of GFRP powder lacks active groups, resulting in weak bonding with asphalt, with interfacial energy typically below 10 mJ / m². 2 This causes stress concentration when directly added to asphalt, reducing the fatigue life of the pavement, typically by more than 40%. Therefore, further research is needed to improve the balance between the high viscoelasticity and wet-heat durability of asphalt by combining the reuse of retired wind turbine blades. Summary of the Invention

[0006] In view of this, the present invention provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions and its preparation method, which simultaneously enhances the high viscoelasticity and humid and hot durability of asphalt in humid and hot regions, significantly improves the high-temperature rutting resistance, water damage resistance and low-temperature crack resistance of asphalt, and achieves the goals of solid waste resource utilization and low carbonization.

[0007] To achieve the above objectives, this invention provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions, comprising the following components in parts by weight: 30-50 parts of decommissioned wind turbine blade powder, 15-25 parts of SEBS-g-MAH, 10-25 parts of waste high-density PE, 5-10 parts of composite plasticizer, 2.5-3.5 parts of coupling agent, 0.5-1 part of antioxidant, and 0.1-0.5 parts of esterification catalyst; wherein the decommissioned wind turbine blade powder is an epoxy resin-based glass fiber composite material with a particle size of 80-200 mesh and a glass fiber aspect ratio controlled at (5-8):1.

[0008] Optionally, the SEBS-g-MAH is prepared by melt grafting maleic anhydride onto a styrene-ethylene-butene-styrene block copolymer; the waste high-density PE is obtained by washing, crushing, and surface oxidation of recycled packaging materials or industrial waste, and the density range of the waste high-density PE is 0.935~0.965 g / cm³. 3 The composite plasticizer is composed of castor oil and pretreated waste engine oil in a mass ratio of (1-4):(6-9); the esterification catalyst is p-toluenesulfonic acid; and the coupling agent is KH-560 type epoxy-siloxane bifunctional coupling agent.

[0009] Optionally, the pretreated waste engine oil is prepared by centrifugally filtering the waste engine oil to remove metal particles, and then removing colloids by activated carbon adsorption, wherein the saturated hydrocarbon content of the waste engine oil is ≥85%.

[0010] To achieve the above objectives, the present invention also provides a method for preparing an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions, comprising the following steps:

[0011] (1) Waste engine oil is centrifuged and filtered to remove metal particles, and then activated carbon is used to adsorb and remove gum to obtain pretreated waste engine oil. The pretreated waste engine oil is mixed with castor oil to obtain a composite plasticizer.

[0012] (2) The decommissioned wind turbine blade powder is mixed with a coupling agent for pretreatment to obtain pretreated decommissioned wind turbine blade powder;

[0013] (3) Surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer are melt-blended to obtain a mixture;

[0014] (4) Add pretreated decommissioned wind turbine blade powder, antioxidant and esterification catalyst to the mixture, and knead to obtain granulated material;

[0015] (5) Granulate the granulated material to obtain environmentally friendly direct-injection high viscoelastic modifier granules.

[0016] Optionally, the centrifugal filtration speed in step (1) is ≥5000 rpm, and the metal impurity content of the pretreated waste oil is ≤0.1%.

[0017] Optionally, in step (2), the conditions for blending the decommissioned wind turbine blade powder with the coupling agent are a temperature of 110~130℃ and a mixing time of 10~20min, and a Si-O-Si bonding interface is formed after blending.

[0018] Optionally, the surface oxidation method of the waste high-density PE in step (3) is ozone oxidation, and the oxidation time is 30~60min; the temperature of the surface oxidation of waste high-density PE, SEBS-g-MAH and composite plasticizer is 160~180℃, and the time is 8~12min.

[0019] Optionally, in step (4), pretreated decommissioned wind turbine blade powder, antioxidant and esterification catalyst are added, and the mixing temperature is 185~195℃ and the time is 15~25min to trigger epoxy-asphalt bonding and MAH dynamic esterification reaction.

[0020] Optionally, the granulation equipment in step (5) is a twin-screw extruder.

[0021] To achieve the above objectives, the present invention also provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions for use in the preparation of asphalt mixtures. The application includes the following steps: dry mixing the environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions with aggregates at 185~195℃ for 30 seconds; adding hot asphalt at 160~170℃ and wet mixing for 90 seconds, resulting in an asphalt mixture with a discharge temperature of 175~185℃.

[0022] The above-described technical solution of the present invention has at least the following beneficial effects:

[0023] 1. The modifier of this invention achieves a balance between high-temperature rutting resistance and low-temperature crack resistance through a rigid-elastic dual-network structure design. Specifically, after the decommissioned wind turbine blade powder (GFRP) is pretreated with KH-560 coupling agent, covalent Si-O-Si bonds are formed on the surface, which are uniformly dispersed in the asphalt to form a rigid skeleton, significantly improving shear resistance. At the same time, the maleic anhydride groups (MAH) of SEBS-g-MAH undergo amidation or esterification reactions with the amino (-NH2) and carboxylic acid (-COOH) groups in the asphalt resin to form a chemically cross-linked elastic network. For example, SEBS-g-MAH reacts with asphaltene to form SEBS-Asphaltene amide bonds (reaction formula: SEBS-g-MAH + Asphaltene-NH2 → SEBS-Asphaltene), endowing asphalt with high elastic recovery ability; waste PE introduces carboxyl groups (-COOH) through surface oxidation, which undergo esterification with the maleic anhydride groups (MAH) of SEBS-g-MAH and the epoxy groups of KH-560, forming a synergistic thickening network of physical entanglement and chemical crosslinking (reaction formula: PE-COOH + MAH → PE-C(O)-O-SEBS). Experimental data show that the highest dynamic stability of 12516 cycles / mm in the examples is 36% higher than that of 9157 cycles / mm in Comparative Example 1, and the dynamic viscosity of asphalt at 60°C increases from 80,000 to 300,000, with the overall viscoelastic index surpassing that of traditional SBS modified asphalt.

[0024] 2. To address the challenge of moisture erosion in humid and hot environments, this invention enhances water resistance through a dual protection mechanism of chemical bonding interface and hydrophobic barrier. The epoxy group (-CH(O)-CH2) of KH-560 reacts with the carboxylic acid in asphalt at high temperatures to form ether or ester bonds (reaction formula: R-COOH + CH2-CH(O)-CH2 → R-CO-O-CH2-CH(OH)-CH2), forming a hydrophobic layer that blocks water molecule penetration. Simultaneously, the Si-O-Si bonds on the GFRP surface exhibit strong resistance to hydrolysis, maintaining an interfacial bonding capacity of 452 kJ / mol under humid and hot conditions (compared to only 10 kJ / mol for traditional physical adsorption). Verification results show that the residual Marshall stability of the asphalt mixture increased from 93.2% in Comparative Example 1 to a maximum of 94.5% in this example, effectively extending the service life of the pavement.

[0025] 3. By introducing a dynamic ester bond network of castor oil / MAH, this invention endows asphalt with the ability to actively repair microcracks. The hydroxyl groups (-OH) in castor oil and the anhydride groups of SEBS-g-MAH form reversible ester bonds under the catalysis of p-toluenesulfonic acid (PTSA) (reaction formula: MAH + HO-R → ROC(O)-CH2-CH(COOH)-). Under high temperature (60℃) or mechanical stress, the ester bonds reversibly break and recombine, achieving self-repair of cracks. Fatigue tests show that its fatigue life is increased from 34,000 cycles to a maximum of 47,000 cycles, demonstrating significantly better durability than traditional asphalt.

[0026] 4. After surface oxidation, the melt index (2-5 g / 10min) of waste PE matches the asphalt mixing temperature (160-180℃). Combined with the long-chain alkane penetration effect of the composite plasticizer (castor oil / waste engine oil), the melt viscosity is significantly reduced, and the modifier is completely dispersed within 90 seconds of mixing.

[0027] 5. This invention overcomes the performance shortcomings of asphalt in humid and hot regions through a four-dimensional synergy of "PE thickening network + GFRP rigid skeleton + SEBS elastic crosslinking + dynamic self-healing", while achieving the goals of high-value utilization and low carbon emissions of decommissioned materials, providing a high-performance, low-cost, and green comprehensive solution for road engineering. Detailed Implementation

[0028] 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 in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0029] Example 1

[0030] This embodiment provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions. Its components and their mass fractions are as follows: retired wind turbine blade powder (GFRP): SEBS-g-MAH: waste high-density PE: composite plasticizer (castor oil: waste engine oil = 2:8): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 50:15:10:8:3.5:0.6:0.2; wherein the retired wind turbine blade powder is an epoxy resin-based glass fiber composite... The material has a particle size of 100 mesh and a glass fiber aspect ratio controlled at 6:1; SEBS-g-MAH is a styrene-ethylene-butene-styrene block copolymer and maleic anhydride obtained by melt grafting; waste high-density PE is recycled packaging materials or industrial waste, which are cleaned, crushed and then surface oxidized; the composite plasticizer is composed of castor oil and pretreated waste machine oil in a mass ratio of 2:8; the esterification catalyst is p-toluenesulfonic acid; the coupling agent is KH-560 type epoxy-siloxane bifunctional coupling agent.

[0031] This embodiment also provides a method for preparing an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions, including the following steps:

[0032] (1) Remove metal particles from waste engine oil by centrifugal filtration. The saturated hydrocarbon content of the waste engine oil is ≥85%. The centrifugal filtration speed is 5000 rpm. Then remove the gum by activated carbon adsorption to obtain pretreated waste engine oil. The metal impurity content of the pretreated waste engine oil is ≤0.1%. Mix the pretreated waste engine oil with castor oil to obtain a composite plasticizer.

[0033] (2) The decommissioned wind turbine blade powder was pretreated by mixing with a coupling agent at a temperature of 110°C and a mixing time of 20 min. After mixing, a Si-O-Si bonding interface was formed to obtain the pretreated decommissioned wind turbine blade powder.

[0034] (3) The density range of waste high-density PE is 0.935 g / cm³. 3 Waste high-density PE was surface-oxidized by ozone oxidation for 30 minutes to obtain surface-oxidized waste high-density PE. The surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer were melt-blended at 160℃ for 12 minutes to obtain a mixture.

[0035] (4) Add pretreated retired wind turbine blade powder, antioxidant and esterification catalyst to the mixture and knead it. The kneading temperature is 195°C and the time is 15 min to obtain granulated material.

[0036] (5) Granulate the granulated material using a twin-screw extruder to obtain environmentally friendly direct-injection high viscoelastic modifier granules.

[0037] In this embodiment, a direct-injection high viscoelastic modifier 1 was produced, and its technical specifications are shown in Table 1.

[0038] The direct-injection high viscoelastic modifier 1 was added to the SBS modified asphalt for modification. The amount added was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0039] The direct-injection high viscoelastic modifier 1 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The specific steps were as follows: dry-mix the direct-injection high viscoelastic modifier with aggregates placed at 185°C for 30 seconds; add hot asphalt at 170°C and wet-mix for 90 seconds. The discharge temperature of the prepared asphalt mixture was 175°C. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0040] Example 2

[0041] This embodiment provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions. Its components and their mass fractions are as follows: retired wind turbine blade powder (GFRP): SEBS-g-MAH: waste high-density PE: composite plasticizer (castor oil: waste engine oil = 4:6): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 30:25:15:6:2.5:0.8:0.5; wherein the retired wind turbine blade powder is an epoxy resin-based glass fiber composite... The material has a particle size of 200 mesh, and the aspect ratio of the glass fiber is controlled at 8:1; SEBS-g-MAH is obtained by melt grafting of styrene-ethylene-butene-styrene block copolymer and maleic anhydride; waste high-density PE is obtained by recycling packaging materials or industrial waste, which is cleaned, crushed and then surface oxidized; the composite plasticizer is composed of castor oil and pretreated waste machine oil in a mass ratio of 4:6; the esterification catalyst is p-toluenesulfonic acid; the coupling agent is KH-560 type epoxy-siloxane bifunctional coupling agent.

[0042] This embodiment also provides a method for preparing an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions, including the following steps:

[0043] (1) Remove metal particles from waste engine oil by centrifugal filtration. The saturated hydrocarbon content of the waste engine oil is ≥85%. The centrifugal filtration speed is 5000 rpm. Then remove the gum by activated carbon adsorption to obtain pretreated waste engine oil. The metal impurity content of the pretreated waste engine oil is ≤0.1%. Mix the pretreated waste engine oil with castor oil to obtain a composite plasticizer.

[0044] (2) The decommissioned wind turbine blade powder was pretreated by mixing with a coupling agent at a temperature of 130°C and a mixing time of 10 min. After mixing, a Si-O-Si bonding interface was formed to obtain the pretreated decommissioned wind turbine blade powder.

[0045] (3) The density of waste high-density PE is 0.965 g / cm³. 3 Waste high-density PE was surface-oxidized by ozone oxidation for 60 minutes to obtain surface-oxidized waste high-density PE. The surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer were melt-blended at 180℃ for 8 minutes to obtain a mixture.

[0046] (4) Add pretreated retired wind turbine blade powder, antioxidant and esterification catalyst to the mixture and knead it. The kneading temperature is 185°C and the time is 25 min to obtain granulated material.

[0047] (5) Granulate the granulated material using a twin-screw extruder to obtain environmentally friendly direct-injection high viscoelastic modifier granules.

[0048] In this embodiment, a direct-injection high viscoelastic modifier 2 was produced, and its technical specifications are shown in Table 1.

[0049] The direct-injection high viscoelastic modifier 2 was added to the SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0050] The direct-injection high viscoelastic modifier 2 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The specific steps were as follows: dry-mix the direct-injection high viscoelastic modifier with aggregate at 190°C for 30 seconds; add hot asphalt at 160°C and wet-mix for 90 seconds. The discharge temperature of the prepared asphalt mixture was 180°C. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0051] Example 3

[0052] This embodiment provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions. Its components and their mass fractions are as follows: retired wind turbine blade powder (GFRP): SEBS-g-MAH: waste high-density PE: composite plasticizer (castor oil: waste engine oil = 1:9): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 35:15:25:10:3:1.0:0.1; wherein the retired wind turbine blade powder is an epoxy resin-based glass fiber composite... The material has a particle size of 80 mesh and a glass fiber aspect ratio controlled at 5:1; SEBS-g-MAH is a styrene-ethylene-butene-styrene block copolymer and maleic anhydride obtained by melt grafting; waste high-density PE is recycled packaging materials or industrial waste, which are cleaned, crushed and then surface oxidized; the composite plasticizer is composed of castor oil and pretreated waste machine oil in a mass ratio of 1:9; the esterification catalyst is p-toluenesulfonic acid; the coupling agent is KH-560 type epoxy-siloxane bifunctional coupling agent.

[0053] This embodiment also provides a method for preparing an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions, including the following steps:

[0054] (1) Remove metal particles from waste oil by centrifugal filtration. The saturated hydrocarbon content of the waste oil is ≥85%. The centrifugal filtration speed is 6000 rpm. Then remove the gum by activated carbon adsorption to obtain pretreated waste oil. The metal impurity content of the pretreated waste oil is ≤0.1%. Mix the pretreated waste oil with castor oil to obtain a composite plasticizer.

[0055] (2) The density of waste high-density PE is 0.945 g / cm³. 3 The decommissioned wind turbine blade powder was pretreated by mixing it with a coupling agent at a temperature of 120℃ for 15 minutes. After mixing, a Si-O-Si bonding interface was formed, and the pretreated decommissioned wind turbine blade powder was obtained.

[0056] (3) The waste high-density PE was oxidized by ozone oxidation for 45 min to obtain surface-oxidized waste high-density PE. The surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer were melt-blended at 170℃ for 10 min to obtain a mixture.

[0057] (4) Add pretreated retired wind turbine blade powder, antioxidant and esterification catalyst to the mixture and knead it. The kneading temperature is 190°C and the time is 20 min to obtain granulated material.

[0058] (5) Granulate the granulated material using a twin-screw extruder to obtain environmentally friendly direct-injection high viscoelastic modifier granules.

[0059] In this embodiment, a direct-injection high viscoelastic modifier 3 was produced, and its technical specifications are shown in Table 1.

[0060] The direct-injection high viscoelastic modifier 3 was added to the SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0061] The direct-injection high viscoelastic modifier 3 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The specific steps were as follows: dry-mix the direct-injection high viscoelastic modifier with aggregate at 195°C for 30 seconds; add hot asphalt at 165°C and wet-mix for 90 seconds. The discharge temperature of the prepared asphalt mixture was 185°C. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0062] Example 4

[0063] This embodiment provides an environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions. Compared with Example 3, the difference lies in the following components and their mass fractions: retired wind turbine blade powder (GFRP): SEBS-g-MAH: waste high-density PE: composite plasticizer (mass ratio of castor oil: waste engine oil = 3:7): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 35: 15: 25: 10: 3: 1.0: 0.1.

[0064] In this embodiment, a direct-injection high viscoelastic modifier 4 was produced. The preparation method of the direct-injection high viscoelastic modifier is the same as that in Example 3, and the technical indicators are shown in Table 1.

[0065] The direct-injection high viscoelastic modifier 4 was added to the SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0066] The direct-injection high viscoelastic modifier 4 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The preparation method of the asphalt mixture was the same as in Example 3. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0067] Comparative Example 1

[0068] SBS modified asphalt (ID type) has the technical indicators shown in Table 2. SMA-13 ​​asphalt mixture was prepared using SBS modified asphalt, and the preparation method of the asphalt mixture was the same as in Example 4.

[0069] Comparative Example 2

[0070] The technical indicators of the high viscoelastic modified asphalt in the prior art are shown in Table 2. SMA-13 ​​asphalt mixture was prepared using the high viscoelastic modified asphalt. The preparation method of the asphalt mixture is the same as that in Example 4.

[0071] Comparative Example 3 (without GFRP)

[0072] Compared with Example 4, the only difference is that the components and their mass fractions in the environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions are as follows: SEBS-g-MAH: waste high-density PE: composite plasticizer (castor oil: waste engine oil = 3:7): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 20: 15: 8: 3: 0.8: 0.3.

[0073] In this embodiment, a direct-injection high viscoelastic modifier 5 was produced. The preparation method of the direct-injection high viscoelastic modifier is the same as that in Example 4, and the technical indicators are shown in Table 1.

[0074] The direct-injection high viscoelastic modifier 5 was added to the SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0075] The direct-injection high viscoelastic modifier 5 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The preparation method of the asphalt mixture was the same as in Example 4. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0076] Comparative Example 4 (without SEBS-g-MAH)

[0077] Compared with Example 4, the only difference is that the components and their mass fractions in the environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions are as follows: retired wind turbine blade powder (GFRP): waste high-density PE: composite plasticizer (castor oil: waste engine oil = 3:7): KH-560 coupling agent: 1010 type antioxidant: esterification catalyst = 40:15:8:3:0.8:0.3.

[0078] In this embodiment, a direct-injection high viscoelastic modifier 6 was produced. The preparation method of the direct-injection high viscoelastic modifier is the same as that in Example 4, and the technical indicators are shown in Table 1.

[0079] The direct-injection high viscoelastic modifier 6 was added to the SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0080] The direct-injection high viscoelastic modifier 6 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The preparation method of the asphalt mixture was the same as in Example 4. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0081] Comparative Example 5 (No Waste PE)

[0082] Compared with Example 4, the only difference is that the components and their mass fractions in the environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions are as follows: according to the ratio of retired wind turbine blade powder (GFRP): SEBS-g-MAH: composite plasticizer (castor oil: waste engine oil = 3:7): KH-560 coupling agent: 1010 type antioxidant: PTSA = 40: 20: 8: 3: 0.8: 0.3.

[0083] In this embodiment, a direct-injection high viscoelastic modifier 7 was produced. The preparation method of the direct-injection high viscoelastic modifier is the same as that in Example 4, and the technical indicators are shown in Table 1.

[0084] The direct-injection high viscoelastic modifier 7 was added to SBS modified asphalt for modification. The addition amount was 6% of the mass of the modified asphalt. The technical indicators of the modified asphalt were measured as shown in Table 2.

[0085] The direct-injection high viscoelastic modifier 7 was added to the modified asphalt SMA-13 ​​asphalt mixture by direct injection. The preparation method of the asphalt mixture was the same as in Example 4. The relevant performance indicators of the asphalt mixture are shown in Table 3.

[0086] The performance of the direct-injection high viscoelastic modifiers prepared in Examples 1-4 and Comparative Examples 3-5 was tested, and the technical indicators were obtained. The data are shown in Table 1.

[0087] Table 1. Performance and technical indicators of the direct-injection high viscoelastic modifiers prepared in Examples 1-4 and Comparative Examples 3-5

[0088]

[0089] The modified asphalt prepared in Examples 1-4 and Comparative Examples 1-5 were subjected to performance tests, and the technical indicators were obtained. The data are shown in Table 2.

[0090] Table 2. Technical performance indicators of the modified asphalt prepared in Examples 1-4 and Comparative Examples 1-5

[0091]

[0092] The asphalt mixtures prepared in Examples 1-4 and Comparative Examples 1-5 were subjected to performance tests, and the technical indicators were obtained. The data are shown in Table 3.

[0093] Table 3. Performance technical indicators of asphalt mixtures prepared in Examples 1-4 and Comparative Examples 1-5

[0094]

[0095] The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions provided by this invention has been tested and shown to significantly improve the overall performance of asphalt binders and asphalt mixtures. The modified asphalt exhibits excellent high-temperature stability and elastic recovery capability. Example 4 shows a dynamic viscosity of 300,000 Pa·s at 60°C, far exceeding that of traditional SBS modified asphalt (Comparative Example 1, 80,000 Pa·s). Example 2 shows an elastic recovery rate of 99.5% at 5°C, demonstrating the breakthrough of this invention in high viscoelastic balance. All examples show superior penetration, softening point, ductility, viscosity, and elastic recovery rate compared to base SBS asphalt, proving that this modifier can comprehensively improve asphalt performance.

[0096] Regarding the road performance of asphalt mixtures, this invention exhibits superior high-temperature rutting resistance. The dynamic stability of the examples all exceeded 10,000 cycles / mm (10,451-12,516 cycles / mm), significantly higher than Comparative Example 1 (9,157 cycles / mm), fully meeting the stringent requirements of high-grade pavements in humid and hot regions. Simultaneously, the modifier endows the mixture with extremely strong resistance to water damage. The water immersion loss rate of Examples 2-4 was as low as 1.05%-1.5%, far superior to Comparative Example 1 (2.1%), thanks to the stable chemical bonding interface constructed by the KH-560 coupling agent. Fatigue life test results (39,000-47,000 cycles) also showed that all examples were superior to the base SBS asphalt (34,000 cycles), indicating a significant improvement in crack resistance and durability.

[0097] Comparative experiments further verified the key roles of each component, proving that the synergistic effect of GFRP, SEBS-g-MAH, and waste PE is indispensable. In summary, this invention successfully utilizes multi-component compounding technology to improve the high-temperature resistance to rutting, water damage, and fatigue of asphalt, while simultaneously achieving high-value utilization of multi-source solid waste such as decommissioned wind turbine blades and waste plastics. This provides a high-performance, green solution for long-life pavement construction in humid and hot regions, demonstrating significant technological advancement and application value.

[0098] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An environmentally friendly direct-application high viscoelastic modifier for asphalt in humid and hot regions, characterized in that, The composition comprises the following components in parts by weight: 30-50 parts of decommissioned wind turbine blade powder, 15-25 parts of SEBS-g-MAH, 10-25 parts of waste high-density PE, 5-10 parts of composite plasticizer, 2.5-3.5 parts of coupling agent, 0.5-1 part of antioxidant, and 0.1-0.5 parts of esterification catalyst; wherein the decommissioned wind turbine blade powder is an epoxy resin-based glass fiber composite material with a particle size of 80-200 mesh and a glass fiber aspect ratio controlled at (5-8):1; SEBS-g-MAH is prepared by melt grafting maleic anhydride onto a styrene-ethylene-butene-styrene block copolymer. The waste high-density PE is obtained from recycled packaging materials or industrial waste, which is then cleaned, crushed, and surface-oxidized. The density range of the waste high-density PE is 0.935~0.965 g / cm³. 3 The composite plasticizer is composed of castor oil and pretreated waste engine oil in a mass ratio of (1-4):(6-9); the esterification catalyst is p-toluenesulfonic acid; the coupling agent is KH-560 type epoxy-siloxane bifunctional coupling agent. The preparation method of environmentally friendly direct-injection high viscoelastic modifier for asphalt in hot and humid regions includes the following steps: (1) removing metal particles from waste oil by centrifugal filtration and removing gum by activated carbon adsorption to obtain pretreated waste oil; mixing the pretreated waste oil with castor oil to obtain a composite plasticizer; (2) pretreating retired wind turbine blade powder with coupling agent to obtain pretreated retired wind turbine blade powder; (3) melting and blending surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer to obtain a mixture; (4) adding pretreated retired wind turbine blade powder, antioxidant and esterification catalyst to the mixture and kneading to obtain granulated material; (5) granulating the granulated material to obtain environmentally friendly direct-injection high viscoelastic modifier granules.

2. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, The waste engine oil has a saturated hydrocarbon content of ≥85%.

3. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, In step (1), the centrifugal filtration speed is ≥5000 rpm, and the metal impurity content of the pretreated waste oil is ≤0.1%.

4. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, In step (2), the conditions for blending the decommissioned wind turbine blade powder with the coupling agent are a temperature of 110~130℃ and a mixing time of 10~20min, and a Si-O-Si bonded interface is formed after blending.

5. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, The surface oxidation method for the waste high-density PE in step (3) is ozone oxidation, and the oxidation time is 30~60min; the temperature for melt blending the surface-oxidized waste high-density PE, SEBS-g-MAH and composite plasticizer is 160~180℃, and the time is 8~12min.

6. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, In step (4), pretreated decommissioned wind turbine blade powder, antioxidant and esterification catalyst are added, and the mixing temperature is 185~195℃ and the time is 15~25min to trigger epoxy-asphalt bonding and MAH dynamic esterification reaction.

7. The environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions according to claim 1, characterized in that, In step (5), the granulation equipment used is a twin-screw extruder.

8. An environmentally friendly direct-injection high viscoelastic modifier for asphalt in humid and hot regions as described in claim 1 or 2, applied to the preparation of asphalt mixtures, characterized in that, The application includes the following steps: dry-mix the environmentally friendly direct-injection high viscoelastic modifier for hot and humid regions with aggregates at 185~195℃ for 30 seconds; add hot asphalt at 160~170℃ and wet-mix for 90 seconds, so that the discharge temperature of the prepared asphalt mixture is 175~185℃.

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