Preparation method of desulfurized rubber powder composite material compounded modified asphalt
By combining bis-(triethoxysilylpropyl)tetrathane with engine oil composite material and styrene-butadiene-styrene block copolymer, the problem of selective bond breaking during the desulfurization of rubber powder was solved, and a high-efficiency desulfurized rubber powder was prepared, which improved the stability and performance of modified asphalt and reduced environmental pollution.
Patent Information
- Application Number
- CN202511239653.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-01
- Publication Date
- 2025-12-12
AI Technical Summary
In existing technologies, selective bond breaking is difficult during the desulfurization process of rubber powder, which leads to the breakage of the main chain of the rubber powder, affecting the performance of modified asphalt, and generating toxic and harmful gases under high temperature conditions, causing environmental pollution.
By using bis-(triethoxysilylpropyl)tetrathane and engine oil composite materials and styrene-butadiene-styrene block copolymers, selective desulfurization of rubber powder is achieved through specific process steps, resulting in high-efficiency desulfurized rubber powder that is then compounded with modified asphalt to form a good phase interface.
Selective desulfurization of rubber powder was achieved, which improved the stability and high and low temperature performance of modified asphalt, reduced construction difficulty and energy consumption, and improved the swelling and dispersion properties of rubber powder in asphalt.
Smart Images
Figure CN121108763A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of devulcanized rubber powder modified asphalt, and particularly relates to a preparation method of a devulcanized rubber powder composite material compounded modified asphalt. BACKGROUND
[0002] With the rapid development of economy, the automobile industry has ushered in rapid development, and the tire industry has also been growing. The waste tires, which are called "black pollution", have caused serious pollution to the environment. On the other hand, the unreasonable tire disposal method is also a waste of resources. Therefore, the preparation of rubber powder from waste tires for recycling is a widely recognized method. However, the un-devulcanized rubber powder has loose texture and poor adhesion. The devulcanization of rubber powder breaks the cross-linking bonds in the internal vulcanized rubber. The devulcanized rubber powder has good swelling and dispersion performance in asphalt, can absorb the light components in asphalt to swell, and form a good phase interface with asphalt to increase the stability of modified asphalt and greatly improve the performance of asphalt.
[0003] At present, high-temperature dynamic devulcanization in a devulcanization tank under normal or high pressure is the most commonly used rubber recycling technology in industrial production. High-temperature pyrolysis and oil swelling are used to break the three-dimensional cross-linked structure. The broken bonds are non-selective, and some toxic and harmful gases are also generated and discharged in the high-temperature environment, causing serious environmental pollution. Selective bond breaking for efficient devulcanization of rubber powder is a major problem to be solved at present.
[0004] The devulcanization methods of rubber powder mainly include physical devulcanization, chemical devulcanization, and biological devulcanization. The physical and mechanical shearing action is combined with chemical reaction to devulcanize the rubber powder with oil and devulcanizing agent. Such methods have higher selectivity in bond breaking, and increasing the shearing time can significantly improve the devulcanization degree. Yue Li et al. (Construction and Building Materials 222 (2019) 588-600) found that the addition of machine oil EO can plasticize the un-devulcanized rubber powder, partially break the S-S chain, and be beneficial to the improvement of low-temperature devulcanization and recyclability. In addition, the addition of machine oil reduces the viscosity of asphalt, and expands the potential application range of rubber powder. However, the addition of machine oil will soften the asphalt and reduce the high-temperature performance of the asphalt. In addition, bis-(triethoxysilylpropyl) tetrasulfane TESPT is used as a rubber powder devulcanizing agent to improve the storage stability of rubber powder modified asphalt, and styrene-butadiene-styrene block copolymer SBS is used to improve the high and low temperature performance of modified asphalt and improve the road construction performance of composite modified asphalt.
[0005] In summary, the TESPT / EO / SBS composite material can significantly improve the properties of the base asphalt by desulfurizing rubber powder. However, achieving efficient desulfurization of the rubber powder through selective bond breaking is the primary issue that needs to be addressed. In existing preparation methods, the main chain of the rubber powder is easily broken during desulfurization. Summary of the Invention
[0006] The purpose of this invention is to provide a method for preparing desulfurized rubber powder from bis-(triethoxysilylpropyl)tetrathane and engine oil composite materials, and then compounding it with styrene-butadiene-styrene block copolymer to modify asphalt. This method can achieve selective bond breaking in the desulfurization of the rubber powder, resulting in efficient desulfurization, while simultaneously improving the performance of the modified asphalt.
[0007] To achieve the above objectives, this invention provides a method for preparing desulfurized rubber powder composite modified asphalt. The technical solution adopted by this invention is as follows: A method for preparing desulfurized rubber powder composite modified asphalt includes the following steps: Step 1: Add bis-(triethoxysilylpropyl)tetrathane and machine oil to the undesulfurized rubber powder, mix initially, and then fully develop in an oven at 80-120 ℃ for 8-24 h.
[0008] Step 2: Mix the rubber powder obtained in Step 1, bis-(triethoxysilylpropyl)tetrathane, and engine oil at a speed of 30-80 rpm and a temperature of 80-120 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0009] Step 3: Transfer the mixed material obtained in Step 2 into a twin-screw extruder. The screw temperature is set to 10 stages: Stage 1 is 160-190 ℃, Stage 2 is 180-200 ℃, and Stages 3-10 are 200-220 ℃. The extrusion speed is 30-70 rpm. Under these conditions, the material is extruded uniformly to obtain desulfurized rubber powder.
[0010] Step 4: Take 10-30 wt% of the desulfurized rubber powder from Step 3, heat the base asphalt to 130 ℃, add the desulfurized rubber powder and styrene-butadiene-styrene block copolymer, raise the temperature to 180-200 ℃, stir and react for 30-60 min to obtain the preliminary modified asphalt.
[0011] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shearing machine. Swell and develop at 180-200℃ for 30-60 minutes to obtain desulfurized rubber powder and styrene-butadiene-styrene block copolymer modified asphalt with good storage stability and high and low temperature performance.
[0012] Preferably, in step one, the mass ratio of undesulfurized rubber powder, bis-(triethoxysilylpropyl)tetrathione to engine oil is 100: 1-5: 5-15.
[0013] Most preferably, in step one, the mass ratio of undesulfurized rubber powder, bis-(triethoxysilylpropyl)tetrathione, and engine oil is 100:3:10.
[0014] Preferably, the rotation speed in step two is 50 rpm and the temperature is 100℃.
[0015] Preferably, in step three, section 1 is 150°C, section 2 is 170°C, and sections 3-10 are 190°C, with an extrusion speed of 60 rpm.
[0016] Preferably, in step four, the mass ratio of desulfurized rubber powder, styrene-butadiene-styrene block copolymer, and matrix asphalt is 10-30: 1-4:100.
[0017] Preferably, the undesulfurized rubber powder in step one is 20-60 mesh.
[0018] Preferably, the styrene-butadiene-styrene block copolymer in step four is linear or star-shaped.
[0019] Preferably, the stirring speed in step four is 500-1000 rpm.
[0020] Preferably, the shearing speed in step five is 2000-5000 rpm.
[0021] The beneficial effects of this invention are as follows: This invention utilizes a composite material of bis-(triethoxysilylpropyl)tetrathane and engine oil to prepare desulfurized rubber powder. The process is simple, the desulfurized rubber powder has good dispersibility and no agglomeration, and the prepared desulfurized rubber powder has a good degree of desulfurization and good high and low temperature performance. It achieves controllable breaking of the cross-linking bonds of the vulcanized rubber powder, which improves its swelling and dispersion in asphalt. The prepared desulfurized rubber powder absorbs the light components in the asphalt and swells, forming a good phase interface with the asphalt. It can significantly improve the stability of the rubber powder modified asphalt and make the viscosity of the modified asphalt easier to control, reducing construction difficulty and energy consumption. Attached Figure Description
[0022] Figure 1 This is a comparison chart of the storage stability of modified asphalt prepared in the embodiments of the present invention and the comparative examples.
[0023] Figure 2 This is a comparison chart of the complex modulus of modified asphalt prepared in the embodiments and comparative examples of the present invention.
[0024] Figure 3This is a phase angle comparison diagram between the modified asphalt prepared in the embodiments of the present invention and the comparative examples.
[0025] Figure 4 This is a comparison chart of the rutting factors of modified asphalt prepared in the embodiments of the present invention and the comparative examples.
[0026] Figure 5 These are the Horrix curves of the modified asphalt prepared in the embodiments and comparative examples of this invention. Detailed Implementation
[0027] To make the technical objectives, technical solutions, and technical effects of the present invention easier to understand, the technical solutions of the present invention will now be further described in conjunction with the accompanying drawings and embodiments.
[0028] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.
[0029] The abbreviations in the following examples and comparative examples represent the following substances: undesulfurized rubber powder (CR), bis-(triethoxysilylpropyl)tetrathione (TSESPT), engine oil (EO), desulfurized rubber powder (DCR), styrene-butadiene-styrene block copolymer (SBS), and modified bitumen (DCRSMA).
[0030] Example 1 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 1 g TSESPT and 5 g EO to 100 g CR. The CR mesh size is 60 mesh. After initial mixing, fully develop in a 90℃ oven for 8 hours.
[0031] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 50 rpm and 80°C to obtain a fully mixed and uniformly dispersed mixture.
[0032] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 160°C, Stage 2 is 180°C, and Stages 3-10 are 200°C. Set the extrusion speed to 30 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0033] Step 4: Take 10 wt% DCR from Step 3, heat 400g of base asphalt to 130℃, add DCR and 1 wt% linear SBS from the base asphalt, raise the temperature to 180℃ and stir the mixture under a stirrer for 30 min at a speed of 500 rpm to obtain the preliminary modified asphalt.
[0034] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shearing machine. Swell and develop at 180℃ for 30 min at a speed of 3000 rpm to obtain DCR and SBS compound DCRSMA with good storage stability and high and low temperature performance.
[0035] The properties of the modified asphalt prepared in Example 1 are shown in Table 1.
[0036] Example 2 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 5 g TSESPT and 15 g EO to 100 g CR. The CR mesh size is 60 mesh. After initial mixing, fully develop in a 90 ℃ oven for 8 h.
[0037] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 50 rpm and 100 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0038] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 170°C, Stage 2 is 190°C, and Stages 3-10 are 210°C. Set the extrusion speed to 50 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0039] Step 4: Take 30 wt% DCR from Step 3, heat 400g of base asphalt to 130℃, add DCR and 4 wt% linear SBS from the base asphalt, raise the temperature to 190℃ and stir the mixture under a stirrer for 30 min at a speed of 800 rpm to obtain the preliminary modified asphalt.
[0040] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shearing machine. Swell and develop at 190℃ for 40 min at a rotation speed of 4500 rpm to obtain DCR and SBS compound DCRSMA with good storage stability and high and low temperature performance.
[0041] The properties of the modified asphalt prepared in Example 2 are shown in Table 1.
[0042] Example 3 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 3 g TSESPT and 10 g EO to 100 g CR. The CR mesh size is 60 mesh. After initial mixing, fully develop in an oven at 110 ℃ for 12 h.
[0043] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 50 rpm and 100 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0044] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 150 ℃, Stage 2 is 170 ℃, and Stages 3-10 are 190 ℃. Set the extrusion speed to 60 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0045] Step 4: Take 20 wt% DCR from Step 3, heat 400g of base asphalt to 130 ℃, add DCR and 3 wt% linear SBS from base asphalt, raise the temperature to 190 ℃ and stir the mixture under a stirrer for 40 min at 600 rpm to obtain the preliminary modified asphalt.
[0046] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shear mill to swell and develop at 190 ℃ for 40 min at a speed of 4000 rpm to obtain DCR and SBS compound DCRSMA with good storage stability and high and low temperature performance.
[0047] The properties of the modified asphalt prepared in Example 3 are shown in Table 1.
[0048] Example 4 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 4 g TSESPT and 8 g EO to 100 g CR. The CR mesh size is 60 mesh. After initial mixing, fully develop in an oven at 100℃ for 12 h.
[0049] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 60 rpm and 110 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0050] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 180 ℃, Stage 2 is 200 ℃, and Stages 3-10 are 220 ℃. Set the extrusion speed to 60 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0051] Step 4: Take 15 wt% DCR from Step 3, heat 400g of base asphalt to 130 ℃, add DCR and 4 wt% star-shaped SBS from the base asphalt, raise the temperature to 200 ℃, and stir the mixture under a stirrer for 30 min at 700 rpm to obtain the preliminary modified asphalt.
[0052] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shear mill to swell and develop at 200 ℃ for 40 min at a speed of 4500 rpm to obtain DCR and SBS compound DCRSMA with good storage stability and high and low temperature performance. The properties of the modified asphalt prepared in Example 4 are shown in Table 1.
[0053] Comparative Example 1 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 6 g TSESPT and 10 g EO to 100 g CR. The CR mesh size is 40 mesh. After initial mixing, fully develop in an oven at 100 ℃ for 10 h.
[0054] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 60 rpm and 120 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0055] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 130 ℃, Stage 2 is 150 ℃, and Stages 3-10 are 170 ℃. Set the extrusion speed to 70 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0056] Step 4: Take 20 wt% DCR from the base asphalt in Step 3, heat 400g of base asphalt to 130 ℃, add DCR and 1 wt% linear SBS from the base asphalt, raise the temperature to 200 ℃ and stir to obtain desulfurized rubber powder pre-modified asphalt DRMA.
[0057] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shear mill to swell and develop at 200 ℃ for 40 min at a speed of 2000 rpm to obtain DCR and SBS compound DCRSMA.
[0058] The properties of the modified asphalt prepared in Comparative Example 1 are shown in Table 1.
[0059] Comparative Example 2 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using TESPT / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 3 g TSESPT and 20 g EO to 100 g CR. The CR mesh size is 80 mesh. After initial mixing, fully develop in an oven at 100 ℃ for 10 h.
[0060] Step 2: Transfer the CR, TESPT, and EO mixture obtained in Step 1 into a Hacker torque rheometer and knead it at 50 rpm and 100 ℃ to obtain a fully mixed and uniformly dispersed mixture. Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 150 ℃, Stage 2 is 170 ℃, and Stages 3-10 are 190 ℃. Set the extrusion speed to 70 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0061] Step 4: Take 20 wt% DCR from the base asphalt in Step 3, heat 400g of base asphalt to 130 ℃, add DCR and 2 wt% linear SBS from the base asphalt, raise the temperature to 190 ℃ and stir the mixture under a stirrer for 30 min to obtain the preliminary modified asphalt.
[0062] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shearing machine to swell and develop at 170 ℃ for 40 min to obtain DCR and SBS compound DCRSMA.
[0063] The properties of the modified asphalt prepared in Comparative Example 2 are shown in Table 1.
[0064] Comparative Example 3 A method for preparing desulfurized rubber powder composite modified asphalt. The method involves preparing DCR using a hexadecylamine / EO composite material and then compounding it with SBS to modify asphalt, including the following steps: Step 1: Add 3 g of hexadecylamine and 10 g of EO to 100 g of CR. The CR mesh size is 60 mesh. After initial mixing, fully develop in an oven at 110 ℃ for 12 h.
[0065] Step 2: The CR, hexadecylamine, and EO mixture obtained in Step 1 is transferred into a Hacker torque rheometer and kneaded at 50 rpm and 100 ℃ to obtain a fully mixed and uniformly dispersed mixture.
[0066] Step 3: Transfer the mixed materials from Step 2 into a twin-screw extruder. Set the screw temperature to 10 stages: Stage 1 is 150 ℃, Stage 2 is 170 ℃, and Stages 3-10 are 190 ℃. Set the extrusion speed to 60 rpm. Under these conditions, extrude the material uniformly to obtain DCR.
[0067] Step 4: Take 20 wt% DCR from Step 3, heat 400g of base asphalt to 130 ℃, add DCR and 3 wt% linear SBS from base asphalt, raise the temperature to 190 ℃ and stir the mixture under a stirrer for 40 min at 600 rpm to obtain the preliminary modified asphalt.
[0068] Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shear mill to swell and develop at 190 ℃ for 40 min at a speed of 4000 rpm to obtain DCR and SBS compound DCRSMA with good storage stability and high and low temperature performance.
[0069] The properties of the modified asphalt prepared in Comparative Example 3 are shown in Table 1.
[0070] Performance comparison of different modified asphalts The performance test results of the modified asphalt prepared in Examples 1-4 and Comparative Examples 1-3 in this invention are as follows: Table 1. Comparison of the four basic properties of different modified asphalts As shown in Table 1, Figure 1 As shown, the TESPT / EO composite materials prepared using the methods of Examples 1, 2, 3, and 4 of this invention, when used to prepare DCR, and when compounded with SBS to modify asphalt, exhibited good high and low temperature performance and storage stability. In contrast, the modified asphalts prepared using the methods of Comparative Examples 1, 2, and 3 showed poor high and low temperature performance and storage stability. Compared to the comparative examples, the softening point, elastic recovery ability, and ductility of the examples were significantly improved. Specifically, Example 3, compared to Comparative Examples 1-3, showed a maximum increase of 38.4% in softening point, 54% in elastic recovery ability, and 64.6% in ductility, greatly enhancing the high-temperature stability and low-temperature crack resistance of the modified asphalt. Figure 1 As can be seen, compared with the comparative example, the difference between the upper and lower softening points of the embodiment is less than 2.5℃, while the difference between the upper and lower softening points of the comparative example is greater than 2.5℃. The reduction in the difference in softening points enhances the miscibility between the rubber powder and the asphalt, and improves the storage stability of the modified asphalt.
[0071] Depend on Figures 2-4 It can be seen that the modified asphalt prepared in the example has a greater complex modulus than that in the comparative example, and also has a larger rutting factor and better resistance to high-temperature deformation.
[0072] Depend onFigure 5 It can be seen that the Horrix curve of the modified asphalt prepared in the comparative example is close to the solid line, indicating a larger proportion of broken chemical bonds on the main chain. This significantly disrupts the network structure of the rubber powder and reduces the high-temperature performance of the modified asphalt. In contrast, the Horrix curve of the modified asphalt prepared in the example is close to the dashed line, indicating that most of the broken bonds are cross-linking bonds, achieving selective breaking of chemical bonds. The partial breaking of cross-linking bonds in the desulfurized rubber powder improves its swelling and dispersion in asphalt. The prepared desulfurized rubber powder absorbs the light components in the asphalt and swells, forming a good phase interface with the asphalt, increasing the storage stability of the modified asphalt. The dense structure formed by SBS enhances the high and low temperature performance of the modified asphalt and improves the road construction performance of the composite modified asphalt.
[0073] In summary, the modified asphalt prepared in Example 3 has good resistance to high-temperature deformation and low-temperature cracking, making it the optimal preparation method.
[0074] The present invention employs a method for preparing DCR using the aforementioned TESPT / EO composite material and then compounding it with SBS to modify asphalt. The process is simple, and the prepared modified asphalt exhibits good comprehensive performance and high stability. Therefore, the preparation process of the present invention is more scientific and reasonable.
[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. A method for preparing desulfurized rubber powder composite modified asphalt, characterized in that, Includes the following steps: Step 1: Add bis-(triethoxysilylpropyl)tetrathane and machine oil to the undesulfurized rubber powder, mix initially, and then fully develop in an oven at 80-120 ℃ for 8-24 h; Step 2: Mix the rubber powder obtained in Step 1, bis-(triethoxysilylpropyl)tetrathane and engine oil mixture at a speed of 30-80 rpm and a temperature of 80-120 ℃ to obtain a fully mixed and uniformly dispersed mixture. Step 3: Transfer the mixed material obtained in Step 2 into a twin-screw extruder. The screw temperature is set to 10 stages: Stage 1 is 160-190 ℃, Stage 2 is 180-200 ℃, and Stages 3-10 are 200-220 ℃. The extrusion speed is 30-70 rpm. Under these conditions, the material is extruded uniformly to obtain desulfurized rubber powder. Step 4: Take 10-30 wt% of the desulfurized rubber powder from Step 3, heat the base asphalt to 130 ℃, add the desulfurized rubber powder and styrene-butadiene-styrene block copolymer, raise the temperature to 180-200 ℃, stir and react for 30-60 min to obtain the preliminary modified asphalt. Step 5: Take the preliminary modified asphalt from Step 4 and transfer it into a shearing machine. Swell and develop at 180-200℃ for 30-60 minutes to obtain desulfurized rubber powder and styrene-butadiene-styrene block copolymer modified asphalt with good storage stability and high and low temperature performance.
2. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, In step one, the mass ratio of undesulfurized rubber powder, bis-(triethoxysilylpropyl)tetrathione to engine oil is 100:1-5:5-15.
3. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 2, characterized in that, In step one, the mass ratio of undesulfurized rubber powder, bis-(triethoxysilylpropyl)tetrathione, and engine oil is 100:3:
10.
4. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, The rotation speed in step two is 50 rpm and the temperature is 100℃.
5. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, In step three, section 1 is 150°C, section 2 is 170°C, and sections 3-10 are 190°C, with an extrusion speed of 60 rpm.
6. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, In step four, the mass ratio of desulfurized rubber powder, styrene-butadiene-styrene block copolymer, and matrix asphalt is 10-30: 1-4:
100.
7. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, The undesulfurized rubber powder in step one is 20-60 mesh.
8. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, The styrene-butadiene-styrene block copolymer in step four is linear or star-shaped.
9. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, In step four, the stirring speed is 500-1000 rpm.
10. The method for preparing desulfurized rubber powder composite modified asphalt according to claim 1, characterized in that, The shearing speed in step five is 2000-5000 rpm.