A modified asphalt, its preparation method and application

Abstract

This invention provides a modified asphalt, its preparation method, and its application. The modified asphalt comprises the following raw materials in parts by weight: 95-105 parts base asphalt, 1-4 parts SBS, 2-4 parts sulfonated SBS, 3-8 parts filler oil, 1-3 parts petroleum resin, and 0.4-0.6 parts antioxidant. The preparation method includes: adding filler oil to sulfonated SBS and SBS respectively, stirring at 90-110℃ for 22-26 hours to obtain mixed solution 1 and mixed solution 2; heating the base asphalt to 120-200℃, sequentially adding mixed solution 1, mixed solution 2, petroleum resin, and antioxidant, stirring for 0.5-1.5 hours, and cooling to obtain the modified asphalt. The modified asphalt prepared by this invention can be used to prepare road paving materials. The modified asphalt prepared by this invention has a good softening point and dynamic viscosity, and also has certain temperature resistance, making it highly valuable for widespread application.

Description

Technical Field

[0001] This invention belongs to the field of road engineering materials technology, specifically relating to a modified asphalt, its preparation method, and its application. Background Technology

[0002] Asphalt-paved roads have advantages such as low dust levels, wear resistance, short construction periods, and seamless construction. However, asphalt materials have poor temperature stability, easily softening in summer. If not properly controlled, this can lead to softening and oil seepage, or even shoving and shearing, damaging the emulsified asphalt. In winter, they are prone to brittleness; low temperatures can cause the asphalt material to become brittle, potentially leading to road surface cracking and, in severe cases, safety hazards. Therefore, modifying asphalt is one of the effective ways to obtain asphalt with better performance.

[0003] Modified asphalt is a composite material with high viscosity and high strength, made primarily from base asphalt by adding SBS elastomer, petroleum resin, and other small-molecule additives. It exhibits good anti-aging and temperature resistance properties, and can significantly improve the performance stability of asphalt, especially in low-temperature environments. However, modified asphalt requires the addition of approximately 5% to 15% SBS elastomer by mass to achieve a significant performance improvement. SBS elastomer itself is a relatively expensive and difficult-to-recycle material; its extensive use not only increases construction costs but also causes a relatively larger white pollution problem. Furthermore, asphalt prepared using this method has a lower softening point and poorer temperature resistance. Summary of the Invention

[0004] To address the above problems, this invention provides a modified asphalt, its preparation method, and its application.

[0005] The technical solution adopted to solve the technical problem is to provide a modified asphalt comprising the following raw materials in parts by weight: 95-105 parts of base asphalt, 1-4 parts of SBS, 2-4 parts of sulfonated SBS, 3-8 parts of filler oil, 1-3 parts of petroleum resin and 0.4-0.6 parts of antioxidant.

[0006] The beneficial effects of the above-mentioned technical solution of the present invention are as follows: adding sulfonated SBS with a certain degree of sulfonation to replace part of the SBS dispersed in the base asphalt, since sulfonated SBS has stronger intermolecular forces, can achieve the effect of reducing the amount of SBS used, while improving the viscosity, anti-aging properties and temperature resistance of the asphalt, so that the performance of the asphalt remains stable in low-temperature environments.

[0007] Preferably, the modified bitumen comprises the following raw materials in parts by weight: 100 parts of base bitumen, 4 parts of SBS, 2 parts of sulfonated SBS, 6 parts of filler oil, 2 parts of petroleum resin and 0.5 parts of antioxidant.

[0008] More preferably, the base asphalt is No. 70 base asphalt; the SBS type is YH-791H; the filler oil is white oil 320; the petroleum resin is C5 type petroleum resin; and the antioxidant is antioxidant 1010.

[0009] Preferably, the degree of sulfonation of sulfonated SBS is 10% to 30%.

[0010] The beneficial effects of the preferred technical solution adopted in this invention are as follows: sulfonated SBS with a sulfonation degree of 10% to 30% has good intermolecular forces. When added to the base asphalt, it can interact with the molecular chains of the asphalt, which can effectively improve the ductility and viscoelasticity of the asphalt.

[0011] More preferably, the degree of sulfonation of sulfonated SBS is 20%.

[0012] The beneficial effects of the preferred technical solution adopted in this invention are as follows: when the sulfonation degree of sulfonated SBS is 20%, it can avoid the problem that if the sulfonation degree is too low, the intermolecular forces of the sulfonated structure will be small; or if the sulfonation degree is too high, the polarity of the sulfonated SBS will be too high, the intermolecular forces will be too high, resulting in low compatibility between sulfonated SBS and base asphalt, filler oil and other materials.

[0013] The preparation method of sulfonated SBS includes the following steps:

[0014] (1) Acetic anhydride was added to 1,2-dichloroethane and stirred evenly in an ice-water bath. Concentrated sulfuric acid was slowly added dropwise and the reaction was continued in an ice-water bath for 30 minutes to obtain the sulfonating reagent. The volume ratio of acetic anhydride to concentrated sulfuric acid was 1.5:1 and the volume ratio of 1,2-dichloroethane to concentrated sulfuric acid was 10:1.

[0015] (2) Add SBS to a mixed solvent of 1,2-dichloroethane and cyclohexane and stir at 50°C to dissolve. Add the above sulfonating reagent and continue stirring for 5 hours. After the reaction is completed, add isopropanol to terminate the reaction and obtain the reaction solution. The ratio of SBS to the mixed solvent of 1,2-dichloroethane and cyclohexane is 2g:30mL, and the volume ratio of 1,2-dichloroethane to cyclohexane is 7:2.

[0016] (3) Pour the reaction solution into boiling water to precipitate and stir. After drying at 60°C for 48 hours, sulfonated SBS granular sample is obtained.

[0017] When the degree of sulfonation of sulfonated SBS is 10%, the ratio of SBS to sulfonating agent in step (2) is 4g:1mL; when the degree of sulfonation of sulfonated SBS is 20%, the ratio of SBS to sulfonating agent in step (2) is 2g:1mL; when the degree of sulfonation of sulfonated SBS is 30%, the ratio of SBS to sulfonating agent in step (2) is 4g:3mL.

[0018] The present invention also provides a method for preparing the above-mentioned modified asphalt, comprising the following steps:

[0019] (1) Add filler oil to sulfonated SBS and stir at 90-110℃ for 22-26h to obtain mixed solution 1;

[0020] (2) Add filler oil to SBS and stir at 90-110℃ for 22-26 hours to obtain mixed solution 2;

[0021] (3) Heat the base asphalt to 120-200℃, add mixed solution 1, mixed solution 2, petroleum resin and antioxidant in sequence, stir for 0.5-1.5h, and obtain modified asphalt after cooling.

[0022] The beneficial effects of the above-mentioned technical solution of the present invention are as follows: First, sulfonated SBS and SBS are thoroughly mixed with filler oil to form a uniform and stable dispersion system, avoiding the generation of bubbles in the subsequent mixing process; at the same time, pre-filling can also reduce energy consumption and environmental pollution in the preparation process, so as to achieve green production; mixing the matrix asphalt with mixed solution 1, mixed solution 2, petroleum resin and antioxidant at 120-200℃ can enhance the molecular thermal motion of the materials, promote mutual penetration, improve their interfacial interaction, and thus improve their adhesion, stability and uniformity.

[0023] Preferably, the stirring temperature in step (1) is 100℃ and the stirring time is 24h; the stirring temperature in step (2) is 100℃ and the stirring time is 24h.

[0024] Preferably, in step (3), the temperature is raised to 140-180°C; the stirring speed is 2500-3500 rpm; and the stirring time is 0.5-1h.

[0025] The present invention also discloses the application of the above-mentioned modified asphalt in the preparation of road paving materials, wherein the road surface includes ultra-thin road surface and permeable road surface.

[0026] The present invention has the following beneficial effects:

[0027] (1) The addition of sulfonated SBS with a sulfonation degree of 20% to the modified asphalt of the present invention can further increase the softening point of the asphalt without reducing its ductility, which is beneficial to the uniform coverage of the modified asphalt when it is used for road paving and to reduce road cracking.

[0028] (2) The addition of sulfonated SBS in this invention can further reduce the amount of SBS used, which is beneficial to reducing construction costs and white pollution problems;

[0029] (3) The modified asphalt prepared by this invention has a good softening point and dynamic viscosity, as well as certain temperature resistance, and has great value for promotion and application. Detailed Implementation

[0030] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0031] Example 1

[0032] A modified asphalt comprises the following raw materials in parts by weight: 100 parts of No. 70 base asphalt, 4 parts of SBS of type YH-791H, 4 parts of sulfonated SBS with a sulfonation degree of 20%, 8 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0033] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0034] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0035] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0036] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0037] The modified asphalt in this embodiment is prepared through the following steps:

[0038] (1) Add 4 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0039] (2) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0040] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 0.5 h using a high-speed shear machine, and obtain modified asphalt after cooling.

[0041] Example 2

[0042] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 4 parts of SBS of type YH-791H, 2 parts of sulfonated SBS with a sulfonation degree of 20%, 6 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0043] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0044] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0045] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0046] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0047] The modified asphalt in this embodiment is prepared through the following steps:

[0048] (1) Add 2 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0049] (2) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0050] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0051] Example 3

[0052] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 2 parts of SBS of type YH-791H, 2 parts of sulfonated SBS with a sulfonation degree of 20%, 4 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0053] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0054] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0055] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0056] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0057] The modified asphalt in this embodiment is prepared through the following steps:

[0058] (1) Add 2 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0059] (2) Add 2 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0060] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0061] Example 4

[0062] A modified asphalt comprises the following raw materials in parts by weight: 100 parts of No. 70 base asphalt, 1 part of SBS of type YH-791H, 2 parts of sulfonated SBS with a sulfonation degree of 20%, 3 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0063] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0064] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0065] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0066] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0067] The modified asphalt in this embodiment is prepared through the following steps:

[0068] (1) Add 2 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0069] (2) Add 1 part of white oil 320 to SBS, put it in an oven and stir at 100°C for 24 hours to obtain mixed solution 2;

[0070] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0071] Example 5

[0072] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 2 parts of SBS of type YH-791H, 2 parts of sulfonated SBS with a sulfonation degree of 10%, 4 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0073] In this embodiment, sulfonated SBS with a sulfonation degree of 10% is obtained through the following steps:

[0074] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0075] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 15mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0076] (3) Pour the reaction solution into boiling water to precipitate and stir. After drying at 60°C for 48 hours, sulfonated SBS with a sulfonation degree of 10% is obtained.

[0077] The modified asphalt in this embodiment is prepared through the following steps:

[0078] (1) Add 2 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 10%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0079] (2) Add 2 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0080] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0081] Example 6

[0082] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 2 parts of SBS of type YH-791H, 2 parts of sulfonated SBS with a sulfonation degree of 30%, 4 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0083] In this embodiment, sulfonated SBS with a sulfonation degree of 30% is obtained through the following steps:

[0084] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0085] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 45mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0086] (3) Pour the reaction solution into boiling water to precipitate and stir. After drying at 60°C for 48 hours, sulfonated SBS with a degree of sulfonation of 30% is obtained.

[0087] The modified asphalt in this embodiment is prepared through the following steps:

[0088] (1) Add 2 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 30%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0089] (2) Add 2 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0090] (3) Heat the base asphalt to 160°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0091] Example 7

[0092] A modified asphalt comprises the following raw materials in parts by weight: 100 parts of No. 70 base asphalt, 4 parts of SBS of type YH-791H, 4 parts of sulfonated SBS with a sulfonation degree of 20%, 8 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0093] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0094] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0095] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0096] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0097] The modified asphalt in this embodiment is prepared through the following steps:

[0098] (1) Add 4 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 90°C for 26 hours to obtain mixed solution 1.

[0099] (2) Add 4 parts of white oil 320 to SBS, put it in an oven and stir at 90°C for 26 hours to obtain mixed solution 2;

[0100] (3) Heat the base asphalt to 120°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 2500 rpm for 1 hour using a high-speed shear machine, and obtain modified asphalt after cooling.

[0101] Example 8

[0102] A modified asphalt comprises the following raw materials in parts by weight: 100 parts of No. 70 base asphalt, 4 parts of SBS of type YH-791H, 4 parts of sulfonated SBS with a sulfonation degree of 20%, 8 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0103] In this embodiment, sulfonated SBS with a sulfonation degree of 20% is obtained through the following steps:

[0104] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0105] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0106] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0107] The modified asphalt in this embodiment is prepared through the following steps:

[0108] (1) Add 4 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 110°C for 22 hours to obtain mixed solution 1;

[0109] (2) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 22 hours at 110°C to obtain mixed solution 2;

[0110] (3) Heat the base asphalt to 200°C, add mixed solution 1, mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3500 rpm for 0.5 h using a high-speed shear machine, and obtain modified asphalt after cooling.

[0111] Comparative Example 1

[0112] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 4 parts of SBS of type YH-791H, 4 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0113] The modified bitumen in this comparative example was prepared through the following steps:

[0114] (1) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0115] (2) Heat the base asphalt to 160°C, add mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir for 1 hour at 3000 rpm using a high-speed shearing machine, and obtain modified asphalt after cooling.

[0116] Comparative Example 2

[0117] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 8 parts of SBS of type YH-791H, 8 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0118] The modified bitumen in this comparative example was prepared through the following steps:

[0119] (1) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0120] (2) Heat the base asphalt to 160°C, add mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir for 1 hour at 3000 rpm using a high-speed shear machine, and obtain modified asphalt after cooling.

[0121] Comparative Example 3

[0122] A modified bitumen comprises the following raw materials in parts by weight: 100 parts of No. 70 base bitumen, 4 parts of sulfonated SBS with a sulfonation degree of 20%, 4 parts of white oil 320, 2 parts of C5 type petroleum resin and 0.5 parts of antioxidant 1010.

[0123] In this comparative example, the sulfonated SBS with a sulfonation degree of 20% was prepared through the following steps:

[0124] (1) Take 3.72 mL of acetic anhydride and add it to 24.8 mL of 1,2-dichloroethane. Stir well under an ice-water bath, slowly add 2.48 mL of concentrated sulfuric acid, and continue the reaction in an ice-water bath for 30 min to obtain the sulfonating reagent.

[0125] (2) Take 60g of SBS and add it to a mixed solvent consisting of 700mL of 1,2-dichloroethane and 200mL of cyclohexane. Stir at 50°C to dissolve. Add 30mL of the above sulfonating agent and continue stirring for 5h. After the reaction is completed, add 100mL of isopropanol to terminate the reaction and obtain the reaction solution.

[0126] (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS with a sulfonation degree of 20%.

[0127] The modified bitumen in this comparative example was prepared through the following steps:

[0128] (1) Add 4 parts of white oil 320 to sulfonated SBS with a sulfonation degree of 20%, and stir in an oven at 100°C for 24 hours to obtain mixed solution 1;

[0129] (2) Heat the base asphalt to 160°C, add mixed solution 1, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 0.5 h using a high-speed shear machine, and obtain modified asphalt after cooling.

[0130] Comparative Example 4

[0131] A modified asphalt comprises the following raw materials in parts by weight: 100 parts of No. 70 base asphalt, 4 parts of SBS of type YH-791H, 4 parts of white oil 320, 2 parts of C5 type petroleum resin, 0.5 parts of antioxidant 1010 and 5 parts of sulfonating agent; wherein the sulfonating agent is a mixture prepared by acetic anhydride and concentrated sulfuric acid in a volume ratio of 1.5:1.

[0132] The modified bitumen in this comparative example was prepared through the following steps:

[0133] (1) Add 4 parts of white oil 320 to SBS, put it in an oven and stir for 24 hours at 100°C to obtain mixed solution 2;

[0134] (2) Heat the base asphalt to 160°C, add mixed solution 2, C5 type petroleum resin and antioxidant 1010 in sequence, stir at 3000 rpm for 0.5 h using a high-speed shear machine, and cool to room temperature.

[0135] (3) Heat the mixture obtained in step (2) to 60°C, add 5 parts of sulfonation reagent, and after the solvent has completely evaporated, heat to 160°C and stir at 3000 rpm for 4 hours using a high-speed shear machine. After cooling, the modified asphalt is obtained.

[0136] Experimental Example

[0137] The methods for determining the properties of modified asphalt in this experiment were all in accordance with the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTJ 052-2000). The properties of the modified asphalt prepared in Examples 1-6 and Comparative Examples 1-4 were determined, and the results are shown in Table 1.

[0138] Table 1

[0139]

[0140] As shown in Table 1, comparing the results of Example 1 and Comparative Example 2, it is evident that replacing part of the SBS with sulfonated SBS can effectively increase the softening point and dynamic viscosity at 60℃ of the high-viscosity modified asphalt, thus effectively improving the temperature resistance of the asphalt. Comparing Examples 2-4 and Comparative Examples 1-2, it is clear that the amount of SBS required to achieve a similar modification effect is significantly reduced after using sulfonated SBS. The modified asphalt prepared in Example 3 only requires 2 parts of SBS to achieve a similar performance modification effect as the modified asphalt in Comparative Example 2, which uses 8 parts of SBS.

[0141] Comparing the results of Examples 3, 5, and Comparative Example 3, it can be seen that 10% sulfonated SBS has a certain effect, but its effect on modification and reducing SBS dosage is not as significant as that of 20% sulfonated SBS used in Example 3. This may be because the sulfonation structure has a limited effect on increasing intermolecular forces. Comparing Examples 3, 6, and Comparative Example 3, it can be seen that 30% sulfonated SBS has a certain modification effect, but the modification effect is not as good as that of 10% and 20% sulfonated SBS. This may be because highly sulfonated SBS has excessive polarity, excessively high intermolecular forces, and low compatibility with asphalt and filler oils.

[0142] Performance tests conducted on the modified asphalt prepared in Comparative Example 3 showed that the performance improvement of the modified asphalt prepared by completely replacing SBS with sulfonated SBS was very limited. This is because without the combined effect of SBS, the sulfonated SBS, which has a large intermolecular interaction force, could not be mixed evenly with the asphalt system and could not play a modifying role.

[0143] Comparative Example 4 involved directly adding sulfonating agents to the raw materials to prepare modified asphalt. The overall sulfonation effect was poor when sulfonating agents were directly added to the modified asphalt system. This is because although the amount of sulfonating agent was large, the matrix asphalt in the formulation contained a large number of sulfonable structures such as benzene rings and naphthalene rings, which could react with the sulfonating agent to generate sulfonic acid groups. However, these sulfonated asphalt molecules lacked mechanical strength and could not play a modifying role. Furthermore, the increased polarity of some asphalt molecules made the asphalt less uniform, ultimately leading to a decrease in performance. Sulfonated groups can only play a modifying role in asphalt by utilizing the unique block structure of SBS when they are present in the benzene ring structure of SBS.

[0144] The present invention has been described according to the above embodiments. It should be understood that the above embodiments do not limit the present invention in any way. All technical solutions obtained by equivalent substitution or equivalent transformation fall within the scope of the present invention.

Claims

1. A modified asphalt, characterized in that, It includes the following raw materials in parts by weight: 95-105 parts of base bitumen, 1-4 parts of SBS, 2-4 parts of sulfonated SBS, 3-8 parts of filler oil, 1-3 parts of petroleum resin and 0.4-0.6 parts of antioxidant. The filler oil is white oil 320; the petroleum resin is C5 type petroleum resin; the sulfonation degree of the sulfonated SBS is 10%~30%; the preparation method of the sulfonated SBS includes the following steps: (1) Acetic anhydride was added to 1,2-dichloroethane and stirred evenly in an ice-water bath. After adding concentrated sulfuric acid dropwise, the reaction was continued in an ice-water bath for 30 minutes to obtain the sulfonating reagent. The volume ratio of acetic anhydride to concentrated sulfuric acid was 1.5:1, and the volume ratio of 1,2-dichloroethane to concentrated sulfuric acid was 10:

1. (2) Add SBS to a mixed solvent of 1,2-dichloroethane and cyclohexane and stir at 50°C to dissolve. Add the sulfonating reagent and continue stirring for 5 hours. After the reaction is completed, add isopropanol to terminate the reaction and obtain the reaction solution. The ratio of SBS to the mixed solvent of 1,2-dichloroethane and cyclohexane is 2g:30mL, and the volume ratio of 1,2-dichloroethane to cyclohexane is 7:

2. (3) Pour the reaction solution into boiling water to precipitate and stir. Dry at 60°C for 48 hours to obtain sulfonated SBS.

2. The modified asphalt as described in claim 1, characterized in that, It includes the following raw materials in parts by weight: 100 parts base bitumen, 4 parts SBS, 2 parts sulfonated SBS, 6 parts filler oil, 2 parts petroleum resin and 0.5 parts antioxidant.

3. The modified asphalt as described in claim 1, characterized in that: The degree of sulfonation of the sulfonated SBS is 20%.

4. The method for preparing modified asphalt according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Add filler oil to sulfonated SBS and stir at 90~110℃ for 22~26h to obtain mixed solution 1; (2) Add filler oil to SBS and stir at 90~110℃ for 22~26h to obtain mixed solution 2; (3) Heat the base asphalt to 120~200℃, add mixed solution 1, mixed solution 2, petroleum resin and antioxidant in sequence, stir for 0.5~1.5h, and obtain modified asphalt after cooling.

5. The method for preparing modified asphalt as described in claim 4, characterized in that: In step (1), the stirring temperature is 100℃ and the stirring time is 24h; in step (2), the stirring temperature is 100℃ and the stirring time is 24h.

6. The method for preparing modified asphalt as described in claim 4, characterized in that: In step (3), the temperature is raised to 140~180℃; the stirring speed is 2500~3500rpm, and the stirring time is 0.5~1h.

7. The application of the modified asphalt according to any one of claims 1 to 3 in the preparation of road paving materials.

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