A method for preparing SBS modified asphalt mortar by modifying copper residue powder with silane coupling agent

Abstract

The application belongs to the field of road engineering and building materials, and particularly relates to a method for preparing SBS modified asphalt mortar by modifying copper residue powder with a silane coupling agent.The application aims to solve the technical problems of traditional mineral powder resource shortage, poor direct utilization effect of copper residue, and insufficient interface compatibility of copper residue powder and SBS modified asphalt.The application uses silane coupling agent KH-550 to modify copper residue powder for SBS modified asphalt mortar, which can realize high-value utilization of solid waste copper residue powder, improve the comprehensive performance of SBS modified asphalt mortar, replace part of mineral powder, and meet the requirements of green low-carbon and circular economy development.The application has simple process, uniform modification, and can be industrialized production, can significantly improve the interface compatibility of copper residue powder and asphalt, improve the high-temperature anti-rutting, low-temperature anti-cracking and anti-fatigue performance of the mortar, realize high-value utilization of industrial solid waste, and is suitable for the field of road engineering.

Description

Technical Field

[0001] This invention belongs to the field of road engineering and building materials, specifically a method for preparing SBS modified asphalt mortar by modifying copper slag powder with a silane coupling agent. Background Technology

[0002] Fillers are a key component of asphalt mastic and asphalt mixtures, playing a crucial role in the strength, adhesion, high-temperature stability, and aging resistance of the mastic. Traditional fillers are mainly limestone powder, relying on mineral mining and crushing, which leads to problems such as high resource consumption, high carbon emissions, and ecological damage to mines. Meanwhile, copper slag, as a major solid waste from the metallurgical industry, is produced in large quantities, its stockpiling occupies land, and it easily causes heavy metal and dust pollution, resulting in low resource utilization rates. Copper slag powder itself has high surface energy and poor compatibility with organic asphalt; directly using it as a filler easily leads to problems such as agglomeration, uneven dispersion, and insufficient asphalt adsorption, resulting in a decline in the mechanical properties and road performance of the mastic. Summary of the Invention

[0003] This invention aims to address the technical problems of scarce traditional mineral powder resources, poor direct utilization of copper slag, and insufficient interfacial compatibility between copper slag powder and SBS modified asphalt, and provides a method for preparing SBS modified asphalt mortar by modifying copper slag powder with a silane coupling agent.

[0004] The method for preparing SBS modified asphalt mortar using silane coupling agent-modified copper slag powder according to the present invention is carried out according to the following steps:

[0005] I. Silane Coupling Agent Modified Copper Slag Powder:

[0006] ① Copper slag powder pretreatment: Place the raw copper slag powder in an oven and dry it to constant weight to remove surface adsorbed water. Let it cool naturally to room temperature, then grind and sieve it to obtain clean and dry copper slag powder.

[0007] ② Preparation of modified solution: Mix deionized water and silane coupling agent and stir until completely dissolved to obtain modified solution;

[0008] ③ Mixing and dispersing: Add the pretreated copper slag powder from step ① to the modified solution from step ② and completely immerse it. Stir at room temperature to completely disperse the copper slag powder, ensuring no dry powder or agglomeration.

[0009] ④ Water bath constant temperature grafting reaction: Transfer the mixture from step ③ into a constant temperature water bath and keep it at 60℃~70℃ for 60min~90min. Stir for 30s~35s every 30min~35min during the reaction to ensure uniform reaction.

[0010] ⑤ Filtration, washing and curing: After the reaction in step ④ is completed, filter the product and retain the solid product. Wash it with deionized water 2 to 3 times to remove unreacted silane coupling agent and soluble impurities. Then dry the product to constant weight, cool it naturally and grind it evenly to obtain silane coupling agent modified copper slag powder.

[0011] II. Preparation of SBS modified asphalt mastic:

[0012] ① Heat the SBS modified bitumen to 175℃~180℃ and keep it at that temperature until it reaches a fluid state;

[0013] ② The copper slag powder modified with silane coupling agent and the mineral powder are mixed evenly to obtain a mixed filler;

[0014] ③ Add the mixed filler from ② to the SBS modified asphalt from ①, and stir for 120s~180s to ensure that the mortar is uniform, without agglomeration or segregation;

[0015] ④ After holding at 175℃~180℃ for 10min~15min to defoam, silane coupling agent modified copper slag powder SBS modified asphalt mortar is obtained.

[0016] This invention uses silane coupling agent KH-550 to perform surface grafting modification on inorganic solid particulate copper slag powder, thereby reducing hydrophilicity and improving interfacial bonding with polymers and asphalt.

[0017] This invention modifies copper slag powder with silane coupling agent KH-550 and uses it in SBS modified asphalt mortar. This not only enables the high-value utilization of solid waste copper slag powder, but also improves the overall performance of SBS modified asphalt mortar, and replaces part of the mineral powder, which meets the requirements of green, low-carbon and circular economy development.

[0018] This invention provides a method for preparing KH-550 modified copper slag powder that is stable, uniformly modified, and industrially feasible, and applies it to SBS modified asphalt mortar to improve the high-temperature, low-temperature, bonding, and water stability performance of the mortar.

[0019] The present invention has a simple process, uniform modification, and can be industrialized. It can significantly improve the interfacial compatibility between copper slag powder and asphalt, enhance the high-temperature resistance to rutting, low-temperature resistance to cracking and fatigue resistance of the adhesive, realize the high-value utilization of industrial solid waste, and is applicable to the field of road engineering. Attached Figure Description

[0020] Figure 1 Figure 1 shows the microstructure of copper slag powder. Figure 2 shows the unmodified raw copper slag powder, and Figure 3 shows the silane coupling agent modified copper slag powder obtained in step 1 of Experiment 1.

[0021] Figure 2 The principal curve of the complex modulus of SBS modified bitumen mastic;

[0022] Figure 3The graph shows the test data for creep recovery rate and irreversible creep compliance of SBS modified bitumen mastic.

[0023] Figure 4 A comparison chart of fatigue life of SBS modified asphalt mortar under different strain levels. Detailed Implementation

[0024] Specific Implementation Method 1: This implementation method describes a method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent, and is carried out according to the following steps:

[0025] I. Silane Coupling Agent Modified Copper Slag Powder:

[0026] ① Copper slag powder pretreatment: Place the raw copper slag powder in an oven and dry it to constant weight to remove surface adsorbed water. Let it cool naturally to room temperature, then grind and sieve it to obtain clean and dry copper slag powder.

[0027] ② Preparation of modified solution: Mix deionized water and silane coupling agent and stir until completely dissolved to obtain modified solution;

[0028] ③ Mixing and dispersing: Add the pretreated copper slag powder from step ① to the modified solution from step ② and completely immerse it. Stir at room temperature to completely disperse the copper slag powder, ensuring no dry powder or agglomeration.

[0029] ④ Water bath constant temperature grafting reaction: Transfer the mixture from step ③ into a constant temperature water bath and keep it at 60℃~70℃ for 60min~90min. Stir for 30s~35s every 30min~35min during the reaction to ensure uniform reaction.

[0030] ⑤ Filtration, washing and curing: After the reaction in step ④ is completed, filter the product and retain the solid product. Wash it with deionized water 2 to 3 times to remove unreacted silane coupling agent and soluble impurities. Then dry the product to constant weight, cool it naturally and grind it evenly to obtain silane coupling agent modified copper slag powder.

[0031] II. Preparation of SBS modified asphalt mastic:

[0032] ① Heat the SBS modified bitumen to 175℃~180℃ and keep it at that temperature until it reaches a fluid state;

[0033] ② The copper slag powder modified with silane coupling agent and the mineral powder are mixed evenly to obtain a mixed filler;

[0034] ③ Add the mixed filler from ② to the SBS modified asphalt from ①, and stir for 120s~180s to ensure that the mortar is uniform, without agglomeration or segregation;

[0035] ④ After holding at 175℃~180℃ for 10min~15min to defoam, silane coupling agent modified copper slag powder SBS modified asphalt mortar is obtained.

[0036] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: in step one ①, the raw copper slag powder is placed in an oven at 105℃ and dried to constant weight to remove surface adsorbed water, then naturally cooled to room temperature, and then ground and passed through a 0.075mm sieve to obtain clean and dry copper slag powder. Everything else is the same as in Specific Implementation Method One.

[0037] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the silane coupling agent mentioned in step one ② is KH-550. Everything else is the same as in Specific Implementation Method One or Two.

[0038] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the mass ratio of the silane coupling agent mentioned in step one ② to the copper slag powder pretreated in step ① is 1:100. Everything else is the same as in Specific Implementation Methods One to Three.

[0039] Specific Implementation Method Five: This implementation method differs from Specific Implementation Method Four in that the volume ratio of the modified solution to the pretreated copper slag powder in step one ③ is 2:1. Everything else is the same as in Specific Implementation Method Four.

[0040] Specific Implementation Method Six: This implementation method differs from Specific Implementation Method Five in that the stirring speed in step one, ④, is 100 r / min to 200 r / min. Everything else is the same as in Specific Implementation Method Five.

[0041] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Method Six in that: in step one, step five, the product is dried at 60°C to constant weight. Everything else is the same as in Specific Implementation Method Six.

[0042] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Method Seven in that the mass ratio of silane coupling agent-modified copper slag powder and mineral powder in step two, ②, is 1:3. Everything else is the same as in Specific Implementation Method Seven.

[0043] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Method Eight in that the mineral powder mentioned in step two ② is limestone mineral powder. Everything else is the same as in Specific Implementation Method Eight.

[0044] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Method Nine in that the mass ratio of the mixed filler to SBS modified asphalt in step two, step three, is 1:1. Everything else is the same as in Specific Implementation Method Nine.

[0045] The invention was verified using the following experiments:

[0046] Experiment 1: This experiment demonstrates a method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent, and is conducted according to the following steps:

[0047] I. Silane Coupling Agent Modified Copper Slag Powder:

[0048] ① Copper slag powder pretreatment: The raw copper slag powder is placed in an oven at 105℃ and dried to constant weight to remove surface adsorbed water. It is then naturally cooled to room temperature, ground and passed through a 0.075mm sieve to obtain clean and dry copper slag powder.

[0049] ② Preparation of modified solution: Mix deionized water and silane coupling agent KH-550 and stir for 2 minutes until completely dissolved to obtain modified solution;

[0050] The mass ratio of the silane coupling agent KH-550 to the copper slag powder pretreated in step ① is 1:100.

[0051] ③ Mixing and dispersing: Add the pretreated copper slag powder from step ① to the modified solution from step ② and immerse it completely. Stir at room temperature for 3 minutes to completely disperse the copper slag powder, ensuring no dry powder or agglomeration.

[0052] The volume ratio of the modified solution to the pretreated copper slag powder is 2:1;

[0053] ④ Water bath constant temperature grafting reaction: Transfer the mixture from step ③ into a constant temperature water bath and keep it at 65℃ for 90 min. Stir for 30 s every 30 min during the reaction to ensure uniform reaction. The stirring speed is 150 r / min.

[0054] ⑤ Filtration, washing and curing: After the reaction in step ④ is completed, filter the product and retain the solid product. Wash it twice with deionized water to remove unreacted silane coupling agent and soluble impurities. Then dry the product at 60°C to constant weight, cool it naturally and grind it evenly to obtain silane coupling agent modified copper slag powder.

[0055] II. Preparation of SBS modified asphalt mastic:

[0056] ① Heat the SBS modified asphalt used in the road to 175℃ and keep it at that temperature until it reaches a fluid state;

[0057] ② Mix the silane coupling agent-modified copper slag powder and mineral powder evenly for 1 minute to obtain a mixed filler;

[0058] The mass ratio of the silane coupling agent-modified copper slag powder to the mineral powder is 1:3;

[0059] The mineral powder mentioned is limestone powder with a density of 2.73 g / cm³. 3 ;

[0060] ③ Add the mixed filler from ② to the SBS modified asphalt from ① and stir for 150 seconds to ensure that the mortar is uniform, without agglomeration or segregation; the mass ratio of the mixed filler to the SBS modified asphalt is 1:1.

[0061] ④ After heat treatment at 175℃ for 10 minutes to remove foam, KH-550 modified copper slag powder SBS mortar is obtained.

[0062] Comparative Experiment: The difference between this experiment and Experiment 1 is that the original copper slag powder was not modified in step one. In step two, the unmodified copper slag powder was mixed with mineral powder as a mixed filler. Everything else was the same as in Experiment 1. Finally, the unmodified copper slag powder SBS mortar was obtained.

[0063] Figure 1 Figure 1 shows the microstructure of copper slag powder. Figure 2 shows the unmodified raw copper slag powder, and Figure 3 shows the silane coupling agent modified copper slag powder obtained in step 1 of Experiment 1. It can be seen that compared with the unmodified copper slag powder, the copper slag particles modified with silane coupling agent have fewer surface deposits, eliminated agglomeration, and improved dispersibility.

[0064] SBS adhesive performance test:

[0065] (1) The dynamic shear rheological properties of asphalt mastic were determined using the T0628-2011 DSR test in the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E3410-2025) to evaluate the viscoelastic properties of the asphalt mastic. The test results are shown in […]. Figure 2 Figure (b) is a magnified view of the dashed box in Figure (a). Figure 2 The results show that the complex modulus master curve of KH-550 modified copper slag powder SBS mortar is continuous and stable. Compared with the unmodified group, the modified group has a slightly higher modulus in the low-frequency region, indicating that its ability to resist shear deformation under long-term load or high-temperature equivalent conditions is enhanced; the modulus in the mid-to-high frequency region is lower than that of the unmodified group, indicating that its stiffness is reduced and its flexibility is improved under low-temperature equivalent conditions. These results indicate that KH-550 modification is beneficial for balancing the high-temperature deformation resistance and low-temperature flexibility of the mortar.

[0066] (2) The asphalt multiple stress creep and recovery test (MSCR test) in T0647-2025 of the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E3410-2025) was adopted to determine the creep recovery rate (R) and irrecoverable creep compliance (Jnr) of asphalt under high temperature conditions. R can evaluate the elastic response of asphalt and its stress dependence, and Jnr can evaluate the resistance to permanent deformation of asphalt under high temperature conditions and its stress dependence. The test results are shown in […]. Figure 3 ,Depend on Figure 3 It can be seen that the asphalt mastic prepared by replacing mineral powder with KH-550 modified copper slag exhibits significantly better high-temperature rutting resistance than the unmodified mastic in the MSCR test. Elastic recovery capability is improved (…). Figure 3(a) and (b) KH-550 modified adhesive showed higher creep recovery rates at stress levels of 0.1 kPa and 3.2 kPa compared to the unmodified adhesive, especially under medium-temperature (52 / 58℃) conditions, where the improvement in elastic recovery was more significant, effectively reducing residual deformation under load. Enhanced resistance to permanent deformation ( Figure 3 (c and d) The Jnr of KH-550 modified asphalt mortar was significantly lower than that of unmodified mortar under all temperature and stress levels, indicating that KH-550 improved the interfacial compatibility between copper slag and asphalt, thereby enhancing the overall stiffness and resistance to permanent deformation of the mortar. High-temperature stability and stress sensitivity were optimized; with increasing temperature and stress level, the performance degradation of KH-550 modified mortar was much smaller than that of unmodified mortar. Especially under high-temperature conditions of 64℃, it still maintained a low Jnr and a high R, indicating that KH-550 modified mortar is more adaptable to high temperatures and heavy traffic, and is more suitable for the high-temperature stability requirements of high-grade asphalt pavements.

[0067] (3) The accelerated damage performance of asphalt under intermediate temperature conditions was determined using the linear strain scanning performance test (LAS test) of asphalt in T0648-2025 of the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E3410-2025) to evaluate the fatigue damage resistance of asphalt. The test results are shown in […]. Figure 4 The results showed that the fatigue life of KH-550 modified copper slag powder SBS asphalt mortar was significantly improved, the modulus decay rate was slower, and the number of fatigue cycles under the same strain was significantly increased. This is attributed to the improved interfacial compatibility and the improved uniformity of filler dispersion, which reduced the stress concentration inside the mortar and significantly enhanced its resistance to fatigue cracking and long-term service durability.

[0068] The above results confirm that the silane coupling agent surface modification process used in this invention significantly improves the interfacial compatibility between copper slag powder and asphalt, optimizes the full-temperature-range viscoelastic properties of the adhesive, and achieves synergistic enhancement of high-temperature rutting resistance, low-temperature crack resistance and fatigue resistance.

Claims

1. A method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent, characterized in that... The method is performed according to the following steps: I. Silane Coupling Agent Modified Copper Slag Powder: ① Copper slag powder pretreatment: Place the raw copper slag powder in an oven and dry it to constant weight to remove surface adsorbed water. Let it cool naturally to room temperature, then grind and sieve it to obtain clean and dry copper slag powder. ② Preparation of modified solution: Mix deionized water and silane coupling agent and stir until completely dissolved to obtain modified solution; ③ Mixing and dispersing: Add the pretreated copper slag powder from step ① to the modified solution from step ② and completely immerse it. Stir at room temperature to completely disperse the copper slag powder, ensuring no dry powder or agglomeration. ④ Water bath constant temperature grafting reaction: Transfer the mixture from step ③ into a constant temperature water bath and keep it at 60℃~70℃ for 60min~90min. Stir for 30s~35s every 30min~35min during the reaction to ensure uniform reaction. ⑤ Filtration, washing and curing: After the reaction in step ④ is completed, filter the product and retain the solid product. Wash it with deionized water 2 to 3 times to remove unreacted silane coupling agent and soluble impurities. Then dry the product to constant weight, cool it naturally and grind it evenly to obtain silane coupling agent modified copper slag powder. II. Preparation of SBS modified asphalt mastic: ① Heat the SBS modified bitumen to 175℃~180℃ and keep it at that temperature until it reaches a fluid state; ② The copper slag powder modified with silane coupling agent and the mineral powder are mixed evenly to obtain a mixed filler; ③ Add the mixed filler from ② to the SBS modified asphalt from ①, and stir for 120s~180s to ensure that the mortar is uniform, without agglomeration or segregation; ④ After holding at 175℃~180℃ for 10min~15min to defoam, silane coupling agent modified copper slag powder SBS modified asphalt mortar is obtained.

2. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... In step 1①, the raw copper slag powder is placed in an oven at 105℃ and dried to constant weight to remove surface adsorbed water. It is then naturally cooled to room temperature, ground, and passed through a 0.075mm sieve to obtain clean and dry copper slag powder.

3. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... The silane coupling agent mentioned in step 1② is KH-550.

4. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 3, characterized in that... The mass ratio of the silane coupling agent mentioned in step 1② to the copper slag powder pretreated in step 1 is 1:

100.

5. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... The volume ratio of the modified solution to the pretreated copper slag powder in step 1③ is 2:

1.

6. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... The stirring speed in step 1, ④ is 100 r / min to 200 r / min.

7. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... In step 1, ⑤, the product is dried at 60°C to constant weight.

8. The method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 1, characterized in that... The mass ratio of silane coupling agent-modified copper slag powder and mineral powder mentioned in step 2② is 1:

3.

9. A method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 8, characterized in that... The mineral powder mentioned in step 2② is limestone mineral powder.

10. A method for preparing SBS modified asphalt mortar using copper slag powder modified with a silane coupling agent according to claim 9, characterized in that... The mass ratio of the mixed filler to SBS modified asphalt mentioned in step 2③ is 1:1.

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