Modified rubber powder and preparation method thereof as well as rubber powder modified asphalt as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of asphalt materials, and particularly relates to modified rubber powder and a preparation method thereof as well as rubber powder modified asphalt as well as a preparation method and application thereof. The rubber powder modified asphalt provided by the invention has excellent storage stability, high temperature resistance and comprehensive performance. By utilizing the modified rubber powder, the storage stability of the rubber powder modified asphalt is remarkably improved, so that the rubber powder modified asphalt can be kept stable for a long time in a storage tank without stirring; through styrene-butadiene-styrene, the high temperature resistance and low temperature resistance of the rubber powder modified asphalt can be remarkably improved; the regenerated low-density polyethylene enhances the high-temperature rut resistance of the rubber powder modified asphalt, significantly reduces the temperature sensitivity of the rubber powder modified asphalt, and improves the high-temperature resistance of the rubber powder modified asphalt; through sulfur, the storage stability of the rubber powder modified asphalt is further effectively improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of asphalt materials, and particularly relates to a modified rubber powder, a preparation method thereof, and a rubber powder modified asphalt, a preparation method and application thereof. BACKGROUND

[0002] Asphalt must maintain a stable quality and performance level throughout the storage period, as changes in its composition can lead to performance differences, affecting the durability and effectiveness of asphalt in road construction. By maintaining storage stability, the quality and performance of asphalt can be ensured, resulting in better and more durable pavements.

[0003] Rubber asphalt is a type of asphalt obtained by incorporating chloroprene rubber (CR) from waste tires into asphalt, which can improve asphalt performance, increase high-temperature stability, mechanical properties, and long-term durability of asphalt, while reducing reflection cracks, ruts, peeling, and road noise, and solving the disposal problem of waste tires, with obvious economic and environmental advantages. However, rubber asphalt has problems such as insufficient storage stability.

[0004] Some researchers use oil (e.g., aromatic oil, naphthenic oil) to pretreat the rubber in rubber asphalt, which activates and enhances the compatibility of CR with asphalt, but the high-temperature resistance of the resulting rubber powder modified asphalt (CRMA) is not good enough to meet the performance requirements of materials in high-temperature regions. SUMMARY

[0005] The present application provides a modified rubber powder, a preparation method thereof, and a rubber powder modified asphalt, a preparation method and application thereof. The modified rubber powder (HCCR) provided by the present application can impart excellent storage stability and high-temperature resistance to rubber powder modified asphalt.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] The present application provides a modified rubber powder, which comprises oil-swollen rubber powder; the oil comprises one or more of edible oil and waste edible oil; the swelling degree of the oil-swollen rubber powder is 12-18% increase in volume.

[0008] Preferably, the source of the rubber powder comprises one or more of waste truck tires and waste car tires; the particle size of the rubber powder is 40-80 mesh.

[0009] Preferably, the particle size of the modified rubber powder is 277.96-465.36 μm.

[0010] The present application also provides a preparation method of the modified rubber powder described in the above-mentioned solution, comprising the following steps:

[0011] Mixing and swelling the rubber powder and oil, the oil including one or several of edible oil and waste edible oil, to obtain the modified rubber powder.

[0012] Preferably, the mass ratio of the rubber powder and oil is 1:0.1-0.5.

[0013] Preferably, the swelling temperature is 80-110℃, and the holding time is 40-75 minutes.

[0014] The application also provides a rubber powder modified asphalt, including 100 parts of asphalt and 20 parts of modified rubber powder by mass fraction; the modified rubber powder is the modified rubber powder in the above scheme or the modified rubber powder obtained by the preparation method in the above scheme.

[0015] When the rubber powder modified asphalt further includes styrene-butadiene-styrene, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder and 2-4 parts of styrene-butadiene-styrene by mass fraction;

[0016] When the rubber powder modified asphalt further includes styrene-butadiene-styrene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 4 parts of styrene-butadiene-styrene and 0.6 parts of sulfur by mass fraction;

[0017] When the rubber powder modified asphalt further includes regenerated low-density polyethylene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 4 parts of regenerated low-density polyethylene and 0.6 parts of sulfur by mass fraction;

[0018] When the rubber powder modified asphalt further includes styrene-butadiene-styrene, regenerated low-density polyethylene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 2 parts of styrene-butadiene-styrene, 2 parts of regenerated low-density polyethylene and 0.6 parts of sulfur by mass fraction.

[0019] The application also provides a preparation method of the rubber powder modified asphalt in the above scheme, including the following steps:

[0020] Heating and mixing the asphalt and modified rubber powder to form a first molding to obtain the rubber powder modified asphalt;

[0021] When the rubber powder modified asphalt further includes styrene-butadiene-styrene, heating and mixing the asphalt, modified rubber powder and styrene-butadiene-styrene to form a second molding to obtain the rubber powder modified asphalt;

[0022] When the rubber powder modified asphalt further includes styrene-butadiene-styrene and sulfur, heating and mixing the asphalt, modified rubber powder, styrene-butadiene-styrene and sulfur to form a third molding to obtain the rubber powder modified asphalt;

[0023] when the crumb rubber modified asphalt further comprises recycled low density polyethylene and sulfur, the crumb rubber modified asphalt is obtained by fourthly forming the asphalt, the modified crumb rubber, the recycled low density polyethylene and the sulfur after being heated and mixed;

[0024] when the crumb rubber modified asphalt further comprises styrene-butadiene-styrene, recycled low density polyethylene and sulfur, the crumb rubber modified asphalt is obtained by fifthly forming the asphalt, the modified crumb rubber, the styrene-butadiene-styrene, the recycled low density polyethylene and the sulfur after being heated and mixed.

[0025] Preferably, the first forming, the second forming, the third forming, the fourth forming and the fifth forming independently comprise first stirring forming, second stirring forming and third stirring forming performed in sequence; the rotation speed of the first stirring forming is 500-800 rpm, and the forming time is 15-30 minutes; the rotation speed of the second stirring forming is 4500-5000 rpm, and the forming time is 60-90 minutes; the rotation speed of the third stirring forming is 500-800 rpm, and the forming time is 15-30 minutes; the temperature of the first forming, the second forming, the third forming, the fourth forming and the fifth forming is independently 170-185 DEG C.

[0026] The application further provides application of the crumb rubber modified asphalt in the road engineering field.

[0027] The application provides a modified crumb rubber.

[0028] The application further provides a preparation method of the modified crumb rubber.

[0029] The application further provides a crumb rubber modified asphalt. The application utilizes the modified crumb rubber, significantly improves the storage stability of the crumb rubber modified asphalt, and enables the crumb rubber modified asphalt to remain stable in a storage tank for a long time without stirring; the application utilizes the styrene-butadiene-styrene (SBS), and can significantly improve the high-temperature resistance and low-temperature resistance of the crumb rubber modified asphalt; the application utilizes the recycled low density polyethylene (RLDPE), enhances the high-temperature rutting resistance of the crumb rubber modified asphalt, significantly reduces the temperature sensitivity of the crumb rubber modified asphalt, and improves the high-temperature resistance of the crumb rubber modified asphalt; and the application utilizes the sulfur, and further effectively improves the storage stability of the crumb rubber modified asphalt.

[0030] The application further provides a preparation method of the rubber powder modified asphalt.

[0031] The application further provides application of the rubber powder modified asphalt or the rubber powder modified asphalt prepared by the preparation method in the field of road engineering. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 FTIR diagram of the modified rubber powder prepared for Examples 1-12. DETAILED DESCRIPTION

[0034] The application provides a modified rubber powder, which comprises oil-swollen rubber powder; the oil comprises one or more of edible oil and waste edible oil; and the swelling degree of the oil-swollen rubber powder is 12-18% in volume increase.

[0035] In the application, the rubber powder can be high-content rubber powder (HUCR); the source of the rubber powder can comprise one or more of waste truck tires and waste automobile tires; and the particle size of the rubber powder can be 40-80 mesh, specifically 50 mesh, 60 mesh or 70 mesh.

[0036] In the application, the swelling degree of the oil-swollen rubber powder is 12-18% in volume increase (relative to the rubber powder before oil swelling), and specifically can be 14% or 16%.

[0037] In the application, the particle size of the modified rubber powder can be 277.96-465.36 μm, and specifically can be 250 μm, 280 μm, 320 μm, 350 μm, 380 μm, 420 μm or 450 μm. The physical and chemical properties of the modified rubber powder provided by the application are shown in Table 1.

[0038] Table 1 Physical and chemical properties of the modified rubber powder

[0039]

[0040] The application further provides a preparation method of the modified rubber powder, comprising the following steps:

[0041] Mixing the rubber powder and oil (denoted as first mixing) to swell, the oil including one or several of edible oil and waste edible oil, to obtain the modified rubber powder.

[0042] In the present application, the rubber powder can further include pre-drying before use; the temperature of the pre-drying can be 40-60℃, specifically 50℃, and the holding time can be 30-45 minutes, specifically 35 minutes or 40 minutes.

[0043] In the present application, the mass ratio of the rubber powder and oil can be 1:0.1-0.5, specifically 1:0.2, 1:0.3 or 1:0.4.

[0044] In the present application, the time of the first mixing can be 10-15 minutes, specifically 12 minutes.

[0045] In the present application, the temperature of the swelling can be 80-110℃, specifically 90℃ or 100℃, and the holding time can be 40-75 minutes, specifically 50 minutes, 60 minutes or 70 minutes.

[0046] The present application further provides a rubber powder modified asphalt, including 100 parts of asphalt and 20 parts of modified rubber powder in terms of mass fraction; the modified rubber powder is the modified rubber powder described in the above scheme or obtained by the preparation method described in the above scheme;

[0047] When the rubber powder modified asphalt further includes styrene-butadiene-styrene, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder and 2-4 parts of styrene-butadiene-styrene in terms of mass fraction;

[0048] When the rubber powder modified asphalt further includes styrene-butadiene-styrene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 4 parts of styrene-butadiene-styrene and 0.6 parts of sulfur in terms of mass fraction;

[0049] When the rubber powder modified asphalt further includes regenerated low-density polyethylene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 4 parts of regenerated low-density polyethylene and 0.6 parts of sulfur in terms of mass fraction;

[0050] When the rubber powder modified asphalt further includes styrene-butadiene-styrene, regenerated low-density polyethylene and sulfur, the rubber powder modified asphalt is 100 parts of asphalt, 20 parts of modified rubber powder, 2 parts of styrene-butadiene-styrene, 2 parts of regenerated low-density polyethylene and 0.6 parts of sulfur in terms of mass fraction.

[0051] The rubber powder modified asphalt provided by the present application comprises asphalt; the penetration (0.1mm, 25℃) grade of the asphalt can be 60-80mm, and can be specifically 65mm, 70mm or 75mm.

[0052] The rubber powder modified asphalt provided by the present application comprises 20 parts of modified rubber powder in terms of mass fraction.

[0053] When the rubber powder modified asphalt further comprises styrene-butadiene-styrene, the rubber powder modified asphalt provided by the present application can comprise 3 parts of styrene-butadiene-styrene in terms of mass fraction of the asphalt.

[0054] In the present application, the basic properties of the styrene-butadiene-styrene are shown in Table 2.

[0055] Table 2 Basic properties of styrene-butadiene-styrene

[0056] Performance parameter Unit Value Melt index 200°C 5 kg g / 10 min 0.1 Butadiene / styrene ratio - 70 / 30 Shore hardness A - 76 Tensile strength MPa 20

[0057] When the rubber powder modified asphalt further comprises recycled low-density polyethylene and sulfur, or when the rubber powder modified asphalt further comprises styrene-butadiene-styrene, recycled low-density polyethylene and sulfur, the basic properties of the RLDPE are shown in Table 3.

[0058] Table 3 Basic properties of RLDPE

[0059] Performance parameter Unit Value Melt flow index (MFI) g / 10 min 1.5 Density g / cm3 1.1 Elongation at break ％ 300 Particle size mm 2-3

[0060] The present application also provides a preparation method of the rubber powder modified asphalt described in the above scheme, comprising the following steps:

[0061] After the asphalt and the modified rubber powder are heated and mixed (denoted as first heating and mixing), molding (denoted as first molding) is performed to obtain the rubber powder modified asphalt;

[0062] When the rubber powder modified asphalt further comprises styrene-butadiene-styrene, after the asphalt, the modified rubber powder and the styrene-butadiene-styrene are heated and mixed (denoted as second heating and mixing), molding (denoted as second molding) is performed to obtain the rubber powder modified asphalt;

[0063] When the rubber powder modified asphalt further comprises styrene-butadiene-styrene and sulfur, after the asphalt, the modified rubber powder, the styrene-butadiene-styrene and the sulfur are heated and mixed (denoted as third heating and mixing), molding (denoted as third molding) is performed to obtain the rubber powder modified asphalt;

[0064] When the rubber powder modified asphalt further comprises recycled low-density polyethylene and sulfur, after the asphalt, the modified rubber powder, the recycled low-density polyethylene and the sulfur are heated and mixed (denoted as fourth heating and mixing), molding (denoted as fourth molding) is performed to obtain the rubber powder modified asphalt;

[0065] When the crumb rubber modified asphalt further includes styrene-butadiene-styrene, recycled low density polyethylene, and sulfur, the asphalt, the modified crumb rubber, the styrene-butadiene-styrene, the recycled low density polyethylene, and the sulfur are heated and mixed (denoted as a fifth heating and mixing) and then molded (denoted as a fifth molding) to obtain the crumb rubber modified asphalt.

[0066] In the present application, the second heating and mixing can include the steps of heating the asphalt to a fluid state at 150 to 160°C, pre-mixing the modified crumb rubber and the asphalt to obtain a pre-mixture, and then mixing the styrene-butadiene-styrene and the pre-mixture.

[0067] In the present application, the temperature of the second heating and mixing can be 155°C.

[0068] In the present application, the third heating and mixing can include the steps of heating the asphalt to a fluid state at 150 to 160°C, pre-mixing the modified crumb rubber and the asphalt to obtain a pre-mixture, and then mixing the styrene-butadiene-styrene and the sulfur and the pre-mixture.

[0069] In the present application, the temperature of the third heating and mixing can be 155°C.

[0070] In the present application, the fourth heating and mixing can include the steps of heating the asphalt to a fluid state at 150 to 160°C, pre-mixing the modified crumb rubber and the asphalt to obtain a pre-mixture, and then mixing the recycled low density polyethylene and the sulfur and the pre-mixture.

[0071] In the present application, the temperature of the fourth heating and mixing can be 155°C.

[0072] In the present application, the fifth heating and mixing can include the steps of heating the asphalt to a fluid state at 150 to 160°C, pre-mixing the modified crumb rubber and the asphalt to obtain a pre-mixture, and then mixing the SBS, the RLDPE, the sulfur, and the pre-mixture.

[0073] In the present application, the temperature of the fifth heating and mixing can be 155°C.

[0074] In the present application, the first forming, the second forming, the third forming, the fourth forming and the fifth forming can independently comprise first stirring forming, second stirring forming and third stirring forming performed in sequence; the rotating speed of the first stirring forming can be 500-800 rpm, specifically 650 rpm, and the forming time can be 15-30 minutes, specifically 22 minutes; the rotating speed of the second stirring forming can be 4500-5000 rpm, specifically 4750 rpm, and the forming time can be 60-90 minutes, specifically 70 minutes or 80 minutes; the rotating speed of the third stirring forming can be 500-800 rpm, specifically 650 rpm, and the forming time can be 15-30 minutes, specifically 22 minutes.

[0075] In the present application, the temperature of the first forming, the second forming, the third forming, the fourth forming and the fifth forming can independently be 170-185℃, specifically 175℃ or 180℃.

[0076] The present application also provides the application of the rubber powder modified asphalt in the road engineering field.

[0077] The rubber powder modified asphalt provided by the present application has enhanced performance, realizes high-value utilization of waste rubber materials, is green and environmentally friendly, and has good economic and social benefits.

[0078] In order to further illustrate the present application, the schemes of the present application are described in detail below in combination with examples, but they should not be understood as limiting the scope of protection of the present application.

[0079] Example 1

[0080] The 60-mesh waste truck tire rubber powder was placed in an oven at 60℃ and baked for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried rubber powder (20% of the mass of the asphalt), and the mass ratio of the rubber powder to the waste cooking oil was 1:0.3, and they were mixed at 100℃ for 10 minutes to obtain a mixture. The mixture was stored in a container and placed in an oven at 100℃ and baked for 60 minutes to obtain modified rubber powder.

[0081] The asphalt with a penetration (0.1mm, 25℃) grade of 60-80 was placed in an oven at 160℃ and heated to a fluid state, and the modified rubber powder was slowly poured into the asphalt, and the obtained mixture was stirred at 500 rpm at 185℃ for 30 minutes. Then, the mixture was transferred to a high-speed shearing machine and stirred at 5000 rpm at 185℃ for 60 minutes, and then stirred at 500 rpm at 185℃ for 30 minutes until forming, to obtain the rubber powder modified asphalt.

[0082] Example 2

[0083] The 60 mesh scrap truck tire crumb rubber was placed in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt) at a mass ratio of 1 :0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and placed in an oven at 100 °C for 60 minutes to obtain a modified crumb rubber.

[0084] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was placed in an oven at 160 °C to heat to a fluid state. The modified crumb rubber was slowly poured into the asphalt, and then SBS (4% by mass of the asphalt) was incorporated into the mixture. The resulting mixture was mixed at 185 °C at 500 rpm for 30 minutes. Then, the mixture was switched to a high speed cutter and mixed at 185 °C at 5000 rpm for 60 minutes. Subsequently, the mixture was stirred at 185 °C at 500 rpm for 30 minutes until molding to obtain crumb rubber modified asphalt.

[0085] Example 3

[0086] The 60 mesh scrap truck tire crumb rubber was placed in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt) at a mass ratio of 1 :0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and placed in an oven at 100 °C for 60 minutes to obtain a modified crumb rubber.

[0087] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was placed in an oven at 160 °C to heat to a fluid state. The modified crumb rubber was slowly poured into the asphalt, and then SBS (4% by mass of the asphalt) was incorporated into the mixture. The resulting mixture was mixed at 185 °C at 500 rpm for 30 minutes. Then, the mixture was switched to a high speed cutter and mixed at 185 °C at 5000 rpm for 60 minutes. Subsequently, the mixture was stirred at 185 °C at 500 rpm for 30 minutes until molding to obtain crumb rubber modified asphalt.

[0088] Example 4

[0089] The 60 mesh scrap truck tire crumb rubber was placed in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt) at a mass ratio of 1 :0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and placed in an oven at 100 °C for 60 minutes to obtain a modified crumb rubber.

[0090] The asphalt having a penetration (0.1 mm, 25°C) grade of 60-80 was heated to a fluid state in an oven at 160°C. The modified crumb rubber was slowly poured into the asphalt, and then SBS (2% by mass of the asphalt) and sulfur (2.5% by mass of the sum of the modified crumb rubber and SBS) were incorporated into the mixture. The resulting mixture was mixed at 185°C for 30 minutes at a speed of 500 rpm. Then, the mixture was switched to a high-speed shearing machine and mixed at 185°C for 60 minutes at a speed of 5000 rpm. Subsequently, the mixture was stirred at 185°C for 30 minutes at a speed of 500 rpm until molding, to obtain crumb rubber-modified asphalt.

[0091] Example 5

[0092] The 60-mesh waste truck tire crumb rubber was baked in an oven at 60°C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3, and the mixture was mixed at 100°C for 10 minutes. The mixture was stored in a container and baked in an oven at 100°C for 60 minutes to obtain modified crumb rubber.

[0093] The asphalt having a penetration (0.1 mm, 25°C) grade of 60-80 was heated to a fluid state in an oven at 160°C. The modified crumb rubber was slowly poured into the asphalt, and then SBS (4% by mass of the asphalt) and sulfur (2.5% by mass of the sum of the modified crumb rubber and SBS) were incorporated into the mixture. The resulting mixture was mixed at 185°C for 30 minutes at a speed of 500 rpm. Then, the mixture was switched to a high-speed shearing machine and mixed at 185°C for 60 minutes at a speed of 5000 rpm. Subsequently, the mixture was stirred at 185°C for 30 minutes at a speed of 500 rpm until molding, to obtain crumb rubber-modified asphalt.

[0094] Example 6

[0095] The 60-mesh waste truck tire crumb rubber was baked in an oven at 60°C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3, and the mixture was mixed at 100°C for 10 minutes. The mixture was stored in a container and baked in an oven at 100°C for 60 minutes to obtain modified crumb rubber.

[0096] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt and then RLDPE (2% by mass of the asphalt) was added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high speed shear mixer and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding to obtain crumb rubber modified asphalt.

[0097] Example 7

[0098] The 60 mesh waste truck tire crumb rubber was baked in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0099] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt and then RLDPE (4% by mass of the asphalt) was added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high speed shear mixer and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding to obtain crumb rubber modified asphalt.

[0100] Example 8

[0101] The 60 mesh waste truck tire crumb rubber was baked in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0102] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt and then RLDPE (2% by mass of the asphalt) and sulphur (2.5% by mass of the sum of the modified crumb rubber and RLDPE) were added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high speed shearing machine and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding to obtain crumb rubber modified asphalt.

[0103] Example 9

[0104] The 60 mesh waste truck tire crumb rubber was baked in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and waste cooking oil was 1:0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0105] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt and then RLDPE (4% by mass of the asphalt) and sulphur (2.5% by mass of the sum of the modified crumb rubber and RLDPE) were added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high speed shearing machine and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding to obtain crumb rubber modified asphalt.

[0106] Example 10

[0107] The 60 mesh waste truck tire crumb rubber was baked in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and waste cooking oil was 1:0.3 and mixed at 100 °C for 10 minutes to obtain a mixture. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0108] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to a fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt, and then SBS (2% by mass of the asphalt), RLDPE (2% by mass of the asphalt), and sulfur (2.5% by mass of the sum of the modified crumb rubber, SBS, and RLDPE) were added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high-speed shearing machine and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding, to obtain crumb rubber-modified asphalt.

[0109] Example 11

[0110] The 60-mesh waste truck tire crumb rubber was placed in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3, and the mixture was mixed at 100 °C for 10 minutes. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0111] The asphalt having a penetration (0.1 mm, 25 °C) grade of 60-80 was heated to a fluid state in an oven at 160 °C. The modified crumb rubber was slowly poured into the asphalt, and then SBS (2% by mass of the asphalt), RLDPE (2% by mass of the asphalt), and sulfur (2.5% by mass of the sum of the modified crumb rubber, SBS, and RLDPE) were added to the mixture. The resulting mixture was mixed at 185 °C for 30 minutes at 500 rpm. Then, the mixture was switched to a high-speed shearing machine and mixed at 185 °C for 60 minutes at 5000 rpm. Subsequently, the mixture was stirred at 185 °C for 30 minutes at 500 rpm until molding, to obtain crumb rubber-modified asphalt.

[0112] Example 12

[0113] The 60-mesh waste truck tire crumb rubber was placed in an oven at 60 °C for 30 minutes to remove moisture. Then, the waste cooking oil was added to the dried crumb rubber (20% by mass of the asphalt). The mass ratio of the crumb rubber and the waste cooking oil was 1:0.3, and the mixture was mixed at 100 °C for 10 minutes. The mixture was stored in a container and baked in an oven at 100 °C for 60 minutes to obtain modified crumb rubber.

[0114] Test Example 1

[0115] Temperature scanning analysis was performed on the rubber-modified asphalt prepared in Examples 1-12 using a TADiscovery HR-20 dynamic shear rheometer (DSR). The strain control mode was used, with a strain of 12%, a frequency of 10 rad / s, and a temperature range of 58–94 °C at 6 °C intervals. 25 mm parallel plates were selected, with a 1 mm gap between the plates. The high-temperature performance rutting factor (G* / sinδ) was tested, and the results are shown in Tables 4-5. The technical performance indicators of the rubber-modified asphalt are shown in Table 6.

[0116] In Tables 4-6, sulfur content is the percentage of S by mass in asphalt; penetration refers to the penetration at 0.1 mm and 25℃; ductility refers to the ductility at 5 cm / min and 5℃; rotational viscosity refers to the rotational viscosity at 180℃; softening point difference refers to the difference between the top and bottom softening points of the rubber-modified asphalt under 48h and 163℃ conditions, which can indicate the storage stability of the rubber-modified asphalt; high-temperature performance rutting factor (G* / sinδ) refers to G* / sinδ under 64℃ conditions.

[0117] Table 4 Physical properties of rubber-modified asphalt in Examples 1-12

[0118]

[0119]

[0120] Table 5 High-temperature resistance properties of rubber-modified asphalt in Examples 1-12

[0121] Example Component G* / sin δ, kPa PG Example 12 20% HUCR 10.89 88 Example 1 20% HCCR 4.6 76 Example 2 20% HCCR + 2% SBS 13.17 88 Example 3 20% HCCR + 4% SBS 21.38 94 Example 4 20% HCCR + 2% SBS + 0.55% S 6.71 88 Example 5 20% HCCR + 4% SBS + 0.6% S 10.25 94 Example 6 20% HCCR + 2% RLDPE 11.16 88 Example 7 20% HCCR + 4% RLDPE 13.35 94 Example 8 20% HCCR + 2% RLDPE + 0.55% S 6.79 82 Example 9 20% HCCR + 4% RLDPE + 0.6% S 8.37 88 Example 10 20% HCCR + 2% SBS + 2% RLDPE 16.66 94 Example 11 20% HCCR + 2% SBS + 2% RLDPE + 0.6% S 10.46 94

[0122] Table 6 Technical Performance Indicators and Specifications of Rubber Powder Modified Asphalt

[0123] No. Performance indicator Unit Specification Standard 1 Penetration mm 60～80 T0604 2 Softening point ℃ >50 T0606 3 Ductility cm >10 T0605 4 Rotational viscosity Pa s 2.5±0.5 T0625 5 Storage stability ℃ ≤3 T0661

[0124] As can be seen from Tables 4-6, Examples 1, 2, 3, 5, 9 and 11 all meet the technical requirements for storage stability of rubber-modified asphalt (T0661), among which Example 5 has the best storage stability and high temperature resistance.

[0125] Test Example 2

[0126] Fourier transform infrared (FTIR) analysis was performed on the modified adhesive powders prepared in Examples 1-12, and the results are as follows: Figure 1 As shown.

[0127] according to Figure 1 As can be seen from the FTIR spectral analysis, the modified asphalt with rubber powder exhibits high viscosity at 1750 cm⁻¹. -1There is an obvious peak, which is attributed to the C=O stretching vibration of ester group; the peak proves that chloroprene rubber is successfully chemically modified by esterification reaction in the process of swelling of the rubber powder; the chemical modification enhances the compatibility and dispersibility of the modified rubber powder in the asphalt, thereby helping to improve the performance of the rubber powder modified asphalt.

[0128] From the above examples, it can be seen that the modified rubber powder provided by the application has good compatibility with asphalt, can be introduced into asphalt at a high doping amount and keep storage stability, so that the rubber powder modified asphalt overcomes the stability problem.

[0129] Although the above examples make a detailed description of the application, it is only a part of the embodiments of the application, not all the embodiments, and other embodiments can be obtained according to the embodiments without creativity, which all belong to the protection scope of the application.

Claims

1. A modified crumb rubber characterized by, The oil swelled rubber powder includes one or more of edible oil and waste edible oil, and the swelling degree of the oil swelled rubber powder is 12-18% of volume increase.

2. The modified crumb rubber of claim 1, wherein, The source of the rubber powder includes one or more of waste truck tire and waste car tire, and the particle size of the rubber powder is 40-80 mesh.

3. The modified crumb rubber of claim 1 or 2, wherein, The particle size of the modified rubber powder is 277.96-465.36 μm.

4. Process for the preparation of the modified powder of any one of claims 1 to 3, characterized in that, The method comprises the following steps: The rubber powder is mixed with oil to swell, the oil including one or more of edible oil and waste edible oil, to obtain the modified rubber powder.

5. The production method according to claim 4, characterized by, The mass ratio of the rubber powder to the oil is 1:0.1-0.

5.

6. The production method according to claim 4 or 5, characterized by, The swelling temperature is 80-110 ℃, and the holding time is 40-75 minutes.

7. A crumb rubber modified asphalt characterized by, According to mass fraction, the asphalt modified rubber powder comprises 100 parts of asphalt and 20 parts of the modified rubber powder, the modified rubber powder being the modified rubber powder according to any one of claims 1-3 or the modified rubber powder obtained by the preparation method according to any one of claims 4-6. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene, the asphalt modified rubber powder comprises, according to mass fraction, 100 parts of asphalt, 20 parts of the modified rubber powder and 2-4 parts of styrene-butadiene-styrene. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene and sulfur, the asphalt modified rubber powder comprises, according to mass fraction, 100 parts of asphalt, 20 parts of the modified rubber powder, 4 parts of styrene-butadiene-styrene and 0.6 part of sulfur. When the asphalt modified rubber powder further comprises recycled low-density polyethylene and sulfur, the asphalt modified rubber powder comprises, according to mass fraction, 100 parts of asphalt, 20 parts of the modified rubber powder, 4 parts of recycled low-density polyethylene and 0.6 part of sulfur. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene, recycled low-density polyethylene and sulfur, the asphalt modified rubber powder comprises, according to mass fraction, 100 parts of asphalt, 20 parts of the modified rubber powder, 2 parts of styrene-butadiene-styrene, 2 parts of recycled low-density polyethylene and 0.6 part of sulfur.

8. The method of claim 7, wherein the crumb rubber modified asphalt is prepared by the steps of: The method comprises the following steps: The asphalt and the modified rubber powder are heated and mixed to form a first molding to obtain the asphalt modified rubber powder. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene, the asphalt, the modified rubber powder and the styrene-butadiene-styrene are heated and mixed to form a second molding to obtain the asphalt modified rubber powder. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene and sulfur, the asphalt, the modified rubber powder, the styrene-butadiene-styrene and the sulfur are heated and mixed to form a third molding to obtain the asphalt modified rubber powder. When the asphalt modified rubber powder further comprises recycled low-density polyethylene and sulfur, the asphalt, the modified rubber powder, the recycled low-density polyethylene and the sulfur are heated and mixed to form a fourth molding to obtain the asphalt modified rubber powder. When the asphalt modified rubber powder further comprises styrene-butadiene-styrene, recycled low-density polyethylene and sulfur, the asphalt, the modified rubber powder, the styrene-butadiene-styrene, the recycled low-density polyethylene and the sulfur are heated and mixed to form a fifth molding to obtain the asphalt modified rubber powder.

9. The production method according to claim 8, characterized by, The first forming, the second forming, the third forming, the fourth forming and the fifth forming independently comprise first stirring forming, second stirring forming and third stirring forming performed in sequence; The rotating speed of the first stirring forming is 500-800 rpm, and the forming time is 15-30 minutes; The rotating speed of the second stirring forming is 4500-5000 rpm, and the forming time is 60-90 minutes; The rotating speed of the third stirring forming is 500-800 rpm, and the forming time is 15-30 minutes; The temperature of the first forming, the second forming, the third forming, the fourth forming and the fifth forming is independently 170-185 ℃.

10. The application of the crumb rubber modified asphalt of claim 7 or the crumb rubber modified asphalt obtained by the preparation method of any one of claims 8-9 in the field of road engineering.

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