Stable rubber asphalt and preparation method thereof

Abstract

The invention relates to the technical field of rubber asphalt, in particular to stable rubber asphalt and a preparation method thereof.The stable rubber asphalt is prepared from road petroleum asphalt, activated rubber powder particles, a modification additive, a compatilizer and a stabilizer according to the following method. Sequentially adding the compatilizer, the activated rubber powder particles and the modification additive into the road petroleum asphalt which is heated to the flowing state, and stirring to a molten state, so as to obtain a mixed material; the preparation method comprises the following steps: mixing the raw materials, then shearing the mixed materials at a high speed, and finally adding a required amount of stabilizer into the sheared mixed materials under a stirring condition for development. The ductility of the stable rubber asphalt at the low temperature of 5 DEG C is 24-31 cm, the softening point is 71-77 DEG C, and the stable rubber asphalt has high and low temperature performance, good stability and excellent performance, and meets the specification of highway engineering asphalt product quality standards.

Description

Technical Field

[0001] The invention relates to the technical field of rubber asphalt and relates to a stable rubber asphalt and a preparation method thereof. Background Art

[0002] Rubber asphalt refers to a rubber asphalt binder for roads that is processed from asphalt, waste rubber powder and other additives. Compared with traditional asphalt pavements, rubber asphalt pavements have reduced pavement thickness and increased service life. They can also significantly improve the high-temperature rutting resistance and low-temperature cracking resistance of asphalt pavements, reducing pavement maintenance costs. Different regional climate zones have different requirements for asphalt materials, and have high requirements for the high and low temperature performance and storage stability of asphalt materials. Traditional rubber asphalt processing temperatures are high (above 185°C) and process conditions are harsh. Not only is energy consumption high, but also special asphalt processing equipment is required. Affected by the rubber powder production process and rubber asphalt processing process, the product has high viscosity and poor construction performance. At the same time, the storage stability problem limits the further development of rubber asphalt.

[0003] The Chinese patent document with publication number CN112457679A discloses a method for preparing high-performance rubber asphalt, including 100 parts of asphalt, 30 to 45 parts of rubber powder, 0.5 to 2 parts of SBS, 0.1 to 1.5 parts of rubber activator, and 0.2 to 0.4 parts of stabilizer. Due to the addition of a large amount of rubber powder, the elasticity of the prepared rubber asphalt is increased and the high-temperature performance is obvious, but there are still problems such as high implementation temperature (insulation temperature 215°C) and unclear low-temperature performance.

[0004] The Chinese patent document with publication number CN114015244A discloses a high-performance rubber asphalt and its preparation method, including: 80 parts of asphalt, 18 to 20 parts of tire rubber powder, 1 to 1.5 parts of eucommia gum, 0.5 to 1.0 parts of butadiene, 0.4 to 0.8 parts of sulfur, 0.05 to 0.1 parts of initiator, and 0.05 to 0.1 parts of antioxidant. The invention uses matured rubber powder, and the high and low temperature performance of the rubber asphalt is improved, but it does not pay attention to the storage stability performance segregation index.

[0005] The Chinese patent document with publication number CN112409807A discloses a high storage stability rubber asphalt and a preparation method thereof, comprising 100 parts of petroleum asphalt, 17 to 23 parts of rubber powder, and 0.5 to 3 parts of an interfacial modifier. The viscosity of the rubber asphalt prepared by the invention is reduced, and the storage stability is improved, but there are still problems such as complex process, numerous operations, no obvious improvement in low temperature performance, and limited application range.

[0006] The Chinese patent document with publication number CN112724694A discloses an environmentally friendly rubber asphalt with stable storage performance and a preparation method thereof. The rubber asphalt components include by weight: 30 to 45 parts of rubber powder, 55 to 70 parts of road petroleum asphalt, 0 to 0.2 parts of modifier, and 0.02 to 0.2 parts of stabilizer. The preparation process is to first mix the rubber powder with the road petroleum asphalt to form a blending system; then add the modifier, and finally add the stabilizer to improve its storage stability. In order to improve the compatibility of the modifier, this method needs to be kept in an oven for 4 to 8 hours for development; the modifier needs to be homogenized twice by a colloid mill before being added to the blending system, which increases the complexity of the operation. The product has a high viscosity of more than 2.5 Pa·S at 180°C, which is not conducive to construction and workability. The low-temperature ductility of 5°C is 18.2cm to 19.4cm, and the softening point is 65.5°C to 69.5°C. The asphalt product has general low-temperature ductility and relatively poor low-temperature crack resistance. Summary of the invention

[0007] The present invention provides a stable rubber asphalt and a preparation method thereof, which overcomes the deficiencies of the above-mentioned prior art and can effectively solve the problems of the existing rubber asphalt such as high high-temperature viscosity, inability to have both high and low temperature performance, and complex manufacturing process.

[0008] The technical solution of the present invention is achieved by the following measures: a stable rubber asphalt, the raw materials include by weight: 100 parts of road petroleum asphalt; 10 to 25 parts of activated rubber powder particles; 1 to 2 parts of modification additive; 3 to 5 parts of compatibilizer; Stabilizer 0.15 to 0.35 parts.

[0009] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions: The above-mentioned road petroleum asphalt is a straight-run asphalt obtained by a normal and vacuum distillation process of cycloalkyl crude oil and intermediate base crude oil in a mass ratio of (3 to 4): (6 to 7). The properties of the straight-run asphalt are a needle penetration of 83 (0.1 mm) at 25°C, a softening point of 48°C, and an elongation of 65 cm at 10°C.

[0010] The above-mentioned modification aid is modification aid SBS, and the modification aid SBS is a linear styrene-butadiene-styrene triblock copolymer.

[0011] The compatibilizer is one of furfural extracted oil, high aromatic oil and catalytic oil slurry with aromatic concentration of more than 50%.

[0012] The above-mentioned stabilizer is a sulfur-containing stabilizer, which is compounded by weight of 80 to 90 parts of sulfur, 1 to 5 parts of vulcanizing resin, 1 to 5 parts of accelerator and 1 to 10 parts of dispersant, the vulcanizing resin is one or more of octylphenol formaldehyde vulcanizing resin and epoxy resin, the accelerator is dibenzothiazole disulfide, and the dispersant is carbon black.

[0013] The above-mentioned stable rubber asphalt is obtained by the following method: S1, under stirring conditions, adding a required amount of a compatibilizer, activated rubber powder particles and a modifying agent in sequence to a required amount of road petroleum asphalt heated to a fluid state, stirring until the mixture is in a molten state, to obtain a mixed material; S2, subjecting the mixed material to high-speed shearing; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt.

[0014] In the above S1, the heating temperature is 135°C to 145°C, the stirring speed is 500 rpm / min to 800 rpm / min, the stirring temperature is 170°C to 175°C, and the stirring time is 15 min to 30 min.

[0015] In the above S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 minutes, then increase the rotation speed to 4000 rpm to 5000 rpm, and then shear the mixed material at a shear temperature of 170° C. to 180° C. for 20 minutes to 30 minutes.

[0016] In the above S3, the stirring speed is 500 rpm / min to 800 rpm / min, the development temperature is 165° C. to 175° C., and the development time is 2 h to 4 h.

[0017] The technical solution of the present invention is achieved by the following measures: A method for preparing a stable rubber asphalt is carried out as follows: S1, under stirring conditions, adding a required amount of a compatibilizer, activated rubber powder particles and a modifying agent in sequence to a required amount of road petroleum asphalt heated to a fluid state, stirring until the mixture is in a molten state, to obtain a mixed material; S2, subjecting the mixed material to high-speed shearing; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt.

[0018] The following is a further optimization and / or improvement of the second technical solution of the above invention: In the above S1, the heating temperature is 135°C to 145°C, the stirring speed is 500 rpm / min to 800 rpm / min, the stirring temperature is 170°C to 175°C, and the stirring time is 15 min to 30 min.

[0019] In the above S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 minutes, then increase the rotation speed to 4000 rpm to 5000 rpm, and then shear the mixed material at a shear temperature of 170° C. to 180° C. for 20 minutes to 30 minutes.

[0020] In the above S3, the stirring speed is 500 rpm / min to 800 rpm / min, the development temperature is 165° C. to 175° C., and the development time is 2 h to 4 h.

[0021] The stabilized rubber asphalt of the present invention has an ductility of 24 cm to 31 cm at a low temperature of 5° C., a softening point of 71° C. to 77° C., has both high and low temperature performance, good stability, and excellent performance, and meets the requirements of the quality standards for asphalt products for highway engineering. DETAILED DESCRIPTION

[0022] The present invention is not limited by the following embodiments, and specific implementation methods can be determined according to the technical scheme of the present invention and actual conditions. Unless otherwise specified, the various chemical reagents and chemicals mentioned in the present invention are all known and commonly used chemical reagents and chemicals in the prior art.

[0023] The present invention will be further described below in conjunction with embodiments: Embodiment 1: The raw materials of the stabilized rubber asphalt include, by weight: 100 parts of road petroleum asphalt; 10 to 25 parts of activated rubber powder particles; 1 to 2 parts of modification additive; 3 to 5 parts of compatibilizer; Stabilizer 0.15 to 0.35 parts.

[0024] Example 2: As an optimization of the above example, road petroleum asphalt is obtained by atmospheric and vacuum distillation of cycloalkyl crude oil and intermediate base crude oil in a mass ratio of (3 to 4): (6 to 7), and the straight-run asphalt has the following properties: a needle penetration of 83 (0.1 mm) at 25°C, a softening point of 48°C, and an elongation of 65 cm at 10°C.

[0025] Example 3: As an optimization of the above example, the modifying agent is a modifying agent SBS, and the modifying agent SBS is a linear styrene-butadiene-styrene triblock copolymer.

[0026] Example 4: As an optimization of the above example, the compatibilizer is one of furfural extracted oil, high aromatic oil and catalytic oil slurry with an aromatic concentration of more than 50%.

[0027] Example 5: As an optimization of the above example, the stabilizer is a sulfur-containing stabilizer, which is compounded by weight of 80 to 90 parts of sulfur, 1 to 5 parts of vulcanizing resin, 1 to 5 parts of accelerator and 1 to 10 parts of dispersant, the vulcanizing resin is one or more of octyl phenolic vulcanizing resin and epoxy resin, the accelerator is dibenzothiazole disulfide, and the dispersant is carbon black.

[0028] Example 6: As an optimization of the above example, the stable rubber asphalt is obtained by the following method: S1, under stirring conditions, adding a required amount of a compatibilizer, activated rubber powder particles and a modifying agent in sequence to a required amount of road petroleum asphalt heated to a fluid state, stirring until the mixture is in a molten state, to obtain a mixed material; S2, subjecting the mixed material to high-speed shearing; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt.

[0029] Example 7: As an optimization of the above example, in S1, the heating temperature is 135°C to 145°C, the stirring speed is 500rpm / min to 800rpm / min, the stirring temperature is 170°C to 175°C, and the stirring time is 15min to 30min.

[0030] Example 8: As an optimization of the above example, in S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 minutes, then increase the rotation speed to 4000 rpm to 5000 rpm, and then shear the mixed material at a shear temperature of 170°C to 180°C for 20 minutes to 30 minutes.

[0031] Example 9: As an optimization of the above example, in S3, the stirring speed is 500 rpm / min to 800 rpm / min, the development temperature is 165°C to 175°C, and the development time is 2h to 4h.

[0032] Compared with the prior art, the present invention has the following beneficial effects: The raw material road petroleum asphalt (base asphalt) of the present invention is a straight-run asphalt produced by a constant pressure reduction device with a certain proportion of cycloalkyl crude oil and intermediate base crude oil. The straight-run asphalt has a reasonable distribution of saturated hydrocarbons, aromatic hydrocarbons, colloids, and asphaltenes. The saturated fraction and aromatic fraction can better swell the raw material activated rubber powder particles and the modified auxiliary agent, and can improve the compatibility of the system. Under the joint action of the compatibilizer and the stabilizer, the system tends to be more stable. The appropriate colloid content of the road petroleum asphalt can ensure the low-temperature performance of the system, and its appropriate asphaltene content plays a skeleton role, interacting with the activated rubber particles to ensure the high-temperature performance of the rubber asphalt product. The stable rubber asphalt of the present invention has an elongation of 24cm to 31cm at a low temperature of 5°C, a softening point of 71°C to 77°C, and both high and low temperature performance.

[0033] The raw material activated rubber powder particles of the present invention undergo a dynamic vulcanization process and are broken and degraded by high temperature and high-speed shearing. The activated rubber powder particles can form micro-nano-level particles in the system and have a good dispersing effect. Therefore, they are quickly miscible with road petroleum asphalt. Compared with traditional rubber asphalt, the swelling and degradation processes are reduced, and the harshness of the process conditions is significantly reduced. At the same time, the surface of the raw material activated rubber powder particles contains a large number of polar functional groups, which can better combine with the polar compounds and modification additives in the asphalt, and are not easy to agglomerate after mixing with asphalt, which can effectively reduce the viscosity of the rubber asphalt obtained by the traditional method. The high-temperature viscosity at 180°C is about 1 Pa•S.

[0034] The characteristics of the raw material road petroleum asphalt (base asphalt) and the activated rubber powder particles determine that the preparation process of the stabilized rubber asphalt of the present invention only needs to be sheared and ground once to obtain the product, and the preparation process is simple.

[0035] Embodiment 10: The stabilized rubber asphalt comprises, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 10 parts of activated rubber powder particles, 1 part of modified auxiliary agent SBS, 3 parts of compatibilizer (furfural extracted oil) and 0.15 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 80 parts by weight of sulfur, 1 part of vulcanized resin (octylphenol formaldehyde vulcanized resin), 1 part of dibenzothiazole disulfide and 1 part of carbon black), and is obtained by the following method: S1, under stirring conditions, first add a required amount of compatibilizer to a required amount of road petroleum asphalt heated to a fluid state, then add a required amount of activated rubber powder particles and a modification aid in batches and stir until the mixture is molten to obtain a mixed material; in the former, in S1, the heating temperature is 135°C, the stirring speed is 500rpm / min, the stirring temperature is 170°C, and the stirring time is 15min; S2, subjecting the mixed material to high-speed shearing; wherein, in S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 min, then increase the rotation speed to 4000 rpm, and then shear the mixed material at a shear temperature of 170° C. for 20 min; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt; wherein, in S3, the stirring speed is 500 rpm / min, the stirring temperature is 165°C, and the development time is 2h.

[0036] Embodiment 11: The stabilized rubber asphalt comprises, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 4:7), 25 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 5 parts of compatibilizer (high aromatic oil) and 0.35 parts of stabilizer (sulfur-containing stabilizer, (the stabilizer is a sulfur-containing stabilizer, and the sulfur-containing stabilizer is composed of 90 parts of sulfur, 5 parts of vulcanized resin (epoxy resin), 5 parts of dibenzothiazole disulfide and 10 parts of carbon black in parts by weight), and is obtained by the following method: S1, under stirring conditions, first add a required amount of compatibilizer to a required amount of road petroleum asphalt heated to a fluid state, then add a required amount of activated rubber powder particles and a modification aid in batches and stir until the mixture is molten to obtain a mixed material; in the former, in S1, the heating temperature is 145°C, the stirring speed is 800 rpm / min, the stirring temperature is 175°C, and the stirring time is 30 min; S2, subjecting the mixed material to high-speed shearing; wherein, in S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 min, then increase the rotation speed to 5000 rpm, and then shear the mixed material at a shear temperature of 180° C. for 30 min; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt; wherein, in S3, the stirring speed is 800 rpm / min, the stirring temperature is 175°C, and the development time is 4h.

[0037] Embodiment 12: The stable rubber asphalt comprises, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3.5:6.5), 15 parts of activated rubber powder particles, 1.5 parts of modified auxiliary agent SBS, 4 parts of compatibilizer (catalytic oil slurry with an aromatic hydrocarbon concentration of more than 50%) and 0.20 parts of stabilizer (sulfur-containing stabilizer, (the stabilizer is a sulfur-containing stabilizer, and the sulfur-containing stabilizer is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenol formaldehyde vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black), and is obtained by the following method: S1, under stirring conditions, first add a required amount of compatibilizer to a required amount of road petroleum asphalt heated to a fluid state, then add a required amount of activated rubber powder particles and a modification aid in batches and stir until the mixture is in a molten state to obtain a mixed material; in the former, in S1, the heating temperature is 140°C, the stirring speed is 600 rpm / min, the stirring temperature is 172°C, and the stirring time is 25 min; S2, subjecting the mixed material to high-speed shearing; wherein, in S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 min, then increase the rotation speed to 4500 rpm, and then shear the mixed material at a shear temperature of 175° C. for 25 min; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt; wherein, in S3, the stirring speed is 600 rpm / min, the stirring temperature is 170°C, and the development time is 3h.

[0038] Embodiment 13: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight: 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 15 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 3 parts of compatibilizer (furfural extracted oil) and 0.15 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 170°C and the shearing time is 30 minutes; in S3, the development temperature is 165°C and the development time is 2 hours, and the remaining steps remain unchanged.

[0039] Embodiment 14: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 10 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 3 parts of compatibilizer (furfural extracted oil) and 0.15 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts of sulfur, 2.5 parts of vulcanized resin (octylphenol aldehyde vulcanized resin), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 170°C and the shearing time is 30 minutes; in S3, the development temperature is 165°C and the development time is 4 hours, and the remaining steps remain unchanged.

[0040] Embodiment 15: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight: 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 10 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 3 parts of compatibilizer (furfural extracted oil) and 0.2 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts of sulfur, 2.5 parts of vulcanized resin (octylphenol aldehyde vulcanized resin), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 170°C and the shearing time is 30 minutes; in S3, the development temperature is 165°C and the development time is 4 hours, and the remaining steps remain unchanged.

[0041] Embodiment 16: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 15 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 4 parts of compatibilizer (furfural extracted oil) and 0.25 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts of sulfur, 2.5 parts of vulcanized resin (epoxy resin), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 170°C and the shearing time is 30 minutes; in S3, the development temperature is 165°C and the development time is 2 hours, and the remaining steps remain unchanged.

[0042] Embodiment 17: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 15 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 4 parts of compatibilizer (furfural extracted oil) and 0.25 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts of sulfur, 2.5 parts of vulcanized resin (epoxy resin), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 170°C and the shearing time is 20 minutes; in S3, the development temperature is 170°C and the development time is 3 hours, and the remaining steps remain unchanged.

[0043] Embodiment 18: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight: 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 20 parts of activated rubber powder particles, 1.5 parts of modified auxiliary agent SBS, 4 parts of compatibilizer (high aromatic oil) and 0.25 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 180°C and the shearing time is 20 minutes; in S3, the development temperature is 170°C and the development time is 2 hours, and the remaining steps remain unchanged.

[0044] Embodiment 19: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 20 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 5 parts of compatibilizer (high aromatic oil) and 0.3 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 180°C and the shearing time is 30 minutes; in S3, the development temperature is 170°C and the development time is 3 hours, and the remaining steps remain unchanged.

[0045] Embodiment 20: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 25 parts of activated rubber powder particles, 1 part of modified auxiliary agent SBS, 5 parts of compatibilizer (high aromatic oil) and 0.35 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 180°C and the shearing time is 30 minutes; in S3, the development temperature is 170°C and the development time is 2 hours, and the remaining steps remain unchanged.

[0046] Embodiment 21: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 25 parts of activated rubber powder particles, 1 part of modified auxiliary agent SBS, 5 parts of compatibilizer (catalytic oil slurry with an aromatic concentration of more than 50%) and 0.35 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 180°C and the shearing time is 30 minutes; in S3, the development temperature is 170°C and the development time is 3 hours, and the remaining steps remain unchanged.

[0047] Embodiment 22: The difference from Embodiment 12 is that, The raw materials of the stabilized rubber asphalt include, by weight, 100 parts of road petroleum asphalt (straight-run asphalt obtained by atmospheric and vacuum distillation of naphthenic crude oil and intermediate base crude oil in a mass ratio of 3:6), 25 parts of activated rubber powder particles, 2 parts of modified auxiliary agent SBS, 5 parts of compatibilizer (catalytic oil slurry with an aromatic concentration of more than 50%) and 0.35 parts of stabilizer (the stabilizer is a sulfur-containing stabilizer, which is composed of 85 parts by weight of sulfur, 2.5 parts of vulcanized resin (octylphenolic vulcanized resin and epoxy resin in a mass ratio of 1:1), 2.5 parts of dibenzothiazole disulfide and 5 parts of carbon black). The preparation conditions are as follows: in S2, the shearing temperature is 180°C and the shearing time is 30 minutes; in S3, the development temperature is 170°C and the development time is 4 hours, and the remaining steps remain unchanged.

[0048] Comparative Example 1: The difference from Example 16 of the present invention is that the raw material road petroleum asphalt adopts 90#A grade asphalt, and the rest remains unchanged.

[0049] Comparative Example 2 is different from Example 16 of the present invention in that the raw material activated rubber powder particles adopt the existing 40-mesh ordinary rubber powder, and the rest remains unchanged.

[0050] Comparative Example 3 is different from Example 16 of the present invention in that the raw material activated rubber powder particles adopt the existing desulfurized rubber powder, and the rest remains unchanged.

[0051] Comparative Example 4 is different from Example 16 of the present invention in that no modifying agent SBS is added to the raw materials, and the rest remains unchanged.

[0052] Example 23: The performance of the stabilized rubber asphalt prepared in Examples 13 to 22 of the present invention was tested according to the method specified in JTG E20-2011 "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering". Meanwhile, the rubber asphalt prepared in Comparative Examples 1 to 4 of the present invention was used as a comparison.

[0053] The test results of the performance test are shown in Tables 1 and 2. It can be seen from Tables 1 and 2 that the stabilized rubber asphalt prepared in Examples 13 to 22 of the present invention has an ductility of 24 cm to 31 cm at a low temperature of 5°C, a softening point of 71°C to 77°C, has both high and low temperature performance, good stability, and meets the requirements of the quality standards for asphalt products for highway engineering.

[0054] Compared with Example 16, the road petroleum asphalt of Comparative Example 1 of the present invention adopts a certain brand of No. 90 Grade A asphalt. The rubber asphalt obtained in Comparative Example 1 has a large needle penetration, a limited improvement in softening point, and an insignificant improvement in high temperature performance, and cannot exert the high temperature anti-rutting performance characteristics of rubber asphalt. At the same time, the 48h softening point difference increases significantly, indicating that the stability of the system is deteriorated. The saturated content and aromatic content in the matrix asphalt (No. 90 Grade A asphalt) component used in Comparative Example 1 are lower than those in the embodiment, and the swelling degree of rubber powder and modifier is relatively low. Under the same conditions, the stability of the system is deteriorated.

[0055] Compared with Example 16, in Comparative Example 2 of the present invention, the activated rubber powder particles adopt the 40-mesh common rubber powder widely used on the market. According to the performance test results of Comparative Example 2, the high-temperature performance of the rubber asphalt obtained in Comparative Example 2 is significantly improved, and the softening point is 82°C, but the corresponding 180°C high-temperature viscosity is also significantly increased, reaching 2.87Pa·S, which brings certain difficulties to the construction performance. The storage stability reaches 20°C, the segregation value is high, and the system stability is difficult to ensure. The 40-mesh common rubber powder is obtained by cutting and crushing the rubber by mechanical means such as extrusion, grinding, shearing, etc., and grinding. The vulcanization molding process is not fundamentally destroyed during the tire processing, and the stable cross-linking structure is still maintained. The rubber powder cannot be evenly dispersed in the asphalt system, but the rubber powder plays a role in skeleton nucleation in the system, the system softening point is significantly increased, and the high-temperature performance is improved. However, during the storage of the rubber asphalt, as the rubber powder degrades, the rubber powder will precipitate from the asphalt and segregate, and the storage stability cannot be guaranteed.

[0056] Compared with Example 16, the activated rubber powder particles in Comparative Example 3 of the present invention use the desulfurized rubber powder commonly used on the market. According to the performance test results of Comparative Example 3, the high and low temperature performance of the rubber asphalt obtained in Comparative Example 3 is improved, but the kinematic viscosity at 180°C is still high, and the 48h softening point difference is 8.4°C, and there is still a problem of storage stability.

[0057] Compared with Example 16, no modifying agent is added to Comparative Example 4 of the present invention. According to the performance test results of Comparative Example 3, the high temperature performance of the rubber asphalt obtained in Comparative Example 3 is reduced, the softening point is reduced by 7°C, and the low temperature performance is also reduced. At the same time, the viscosity at 180°C increases to 1.64 Pa·S, and at the same time, the difference between the upper and lower softening points of storage stability increases. The presence of SBS and styrene-butadiene rubber in the modifying agent can make the network structure formed by the rubber powder asphalt more complete and developed, and the high temperature performance of the system is more significantly improved; styrene-butadiene rubber has a significant effect on improving the low temperature performance of asphalt; the presence of the additive can also prevent the rubber powder from further settling in the asphalt. The rubber powder particles and the modifying agent work together to make the system network more developed and the effect more stable.

[0058] In summary, the stabilized rubber asphalt of the present invention has an ductility of 24 cm to 31 cm at a low temperature of 5°C and a softening point of 71°C to 77°C. It has both high and low temperature properties, good stability, and excellent performance, and meets the requirements of the quality standards for asphalt products for highway engineering.

[0059] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A stable rubber asphalt, characterized in that The raw materials include by weight: 100 parts of road petroleum asphalt; 10 to 25 parts of activated rubber powder particles; 1 to 2 parts of modification additive; 3 to 5 parts of compatibilizer; Stabilizer 0.15 to 0.35 parts.

2. The stabilized rubber asphalt according to claim 1, characterized in that The road petroleum asphalt is a straight-run asphalt obtained by atmospheric and vacuum distillation of cycloalkyl crude oil and intermediate base crude oil in a mass ratio of 3 to 4:6 to 7; or / and, the modification aid is modification aid SBS, and the modification aid SBS is a linear styrene-butadiene-styrene triblock copolymer.

3. The stabilized rubber asphalt according to claim 1 or 2, characterized in that The compatibilizer is one of furfural extracted oil, high aromatic oil and catalytic oil slurry with aromatic concentration of more than 50%; or / and, the stabilizer is a sulfur-containing stabilizer, which is compounded by weight of 80 to 90 parts of sulfur, 1 to 5 parts of vulcanized resin, 1 to 5 parts of accelerator and 1 to 10 parts of dispersant, the vulcanized resin is one or more of octylphenol formaldehyde vulcanized resin and epoxy resin, the accelerator is dibenzothiazole disulfide, and the dispersant is carbon black.

4. The stabilized rubber asphalt according to claim 1, 2 or 3, characterized in that Obtained as follows: S1, under stirring conditions, adding a required amount of a compatibilizer, activated rubber powder particles and a modifying agent in sequence to a required amount of road petroleum asphalt heated to a fluid state, stirring until the mixture is in a molten state, to obtain a mixed material; S2, subjecting the mixed material to high-speed shearing; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt.

5. The stabilized rubber asphalt according to claim 4, characterized in that In S1, the heating temperature is 135°C to 145°C, the stirring speed is 500 rpm / min to 800 rpm / min, the stirring temperature is 170°C to 175°C, and the stirring time is 15 min to 30 min.

6. The stabilized rubber asphalt according to claim 4 or 5, characterized in that In S2, the shearing procedure is to first shear the mixed material at a rotation speed of 1000 rpm for 5 minutes, then increase the rotation speed to 4000 rpm to 5000 rpm, and then shear the mixed material at a shear temperature of 170° C. to 180° C. for 20 minutes to 30 minutes.

7. The stabilized rubber asphalt according to claim 4, 5 or 6, characterized in that In S3, the stirring speed is 500 rpm / min to 800 rpm / min, the development temperature is 165° C. to 175° C., and the development time is 2 h to 4 h.

8. A method for preparing the stabilized rubber asphalt according to claim 1 or 2 or 3 or 5 or 6 or 7, characterized in that Proceed as follows: S1, under stirring conditions, adding a required amount of a compatibilizer, activated rubber powder particles and a modifying agent in sequence to a required amount of road petroleum asphalt heated to a fluid state, stirring until the mixture is in a molten state, to obtain a mixed material; S2, subjecting the mixed material to high-speed shearing; S3, under stirring conditions, adding a required amount of stabilizer to the sheared mixture for development to obtain a stabilized rubber asphalt.

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