Composite improved asphalt and preparation method thereof

Abstract

The invention discloses composite improved asphalt and a preparation method thereof, and belongs to the technical field of asphalt preparation. The composite improved asphalt comprises the following components in percentage by mass: 70-80% of matrix asphalt, 10-15% of a temperature-resistant modifier, 5-8% of hydrated silicon dioxide, 1-3% of aromatic oil, 1-3% of an elastic agent, 1-3% of a plasticizer, 0.2-0.8% of nano calcium carbonate and 0.1-1% of silicone acrylic emulsion. According to the invention, the high-temperature-resistant modifier prepared from a mixed reactant of SBR and polymer resin or the low-temperature-resistant modifier prepared from a mixed reactant of SBS and EPDM is adopted, so that the high-temperature resistance and low-temperature resistance of the asphalt are improved, the tolerance temperature of the asphalt is improved, the bearing capacity of an asphalt pavement is increased, and the service life of the asphalt pavement is prolonged. The use effect of the asphalt pavement is improved, the service life of the asphalt pavement is prolonged, and the asphalt pavement is suitable for targeted selection in some cold or high-temperature areas.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt preparation, and in particular to a composite improved asphalt and a preparation method thereof. Background Art

[0002] With the continuous development of society, highway construction has also developed rapidly. People's daily travel and production and life have increasingly prominent demands for highway construction. Therefore, it is very important to improve the flatness of highway pavement and ensure the safety and comfort of people's travel and highway transportation. Among them, asphalt pavement is paved by mixing road asphalt materials into mineral materials. The asphalt binder enhances the ability of the road surface to resist damage from driving and natural factors, making the road surface smooth, less dusty, impermeable and durable.

[0003] Ordinary asphalt is mainly made of residues from the petroleum refining process. This material contains a large amount of volatile organic compounds, which are easily decomposed and oxidized under temperature changes and ultraviolet rays, leading to aging and performance degradation of the asphalt. It is also easily affected by temperature and undergoes volume changes, expansion at high temperatures, contraction at low temperatures, and cracking. Especially when repairing local road cracks, asphalt sealing materials are prone to brittle cracking in winter and softening and squeezing out in summer. They often lose their effectiveness under a 1-2 year climate cycle. In daily use, asphalt pavements need to withstand heavy pressure and friction from vehicles. Long-term traffic loads can also cause asphalt wear, compression and deformation, thereby affecting the performance and service life of the pavement. For some areas with low or high temperatures all year round, the aging and performance degradation of asphalt are more serious.

[0004] To this end, we propose a composite modified asphalt and a preparation method thereof to solve the above-mentioned problems. Summary of the invention

[0005] The embodiment of the present invention provides a composite modified asphalt and a preparation method thereof to solve the above-mentioned technical problems.

[0006] The embodiment of the present invention adopts the following technical solution: including: A composite modified asphalt, the modified asphalt is composed of the following components in percentage by mass: Base asphalt 70%-80%; Temperature resistance modifier 10%-15%; Hydrated silicon dioxide 5%-8%; Aromatic oil 1%-3%; Elasticizer 11%-3%; Plasticizer 1%-3%; Nano calcium carbonate 0.2%-0.8%; Silicone acrylic emulsion 0.1%-1%.

[0007] Furthermore, the modified asphalt is composed of the following components in percentage by mass: Base asphalt 75%; Temperature resistance modifier 12%; Hydrated silicon dioxide 6%; Aromatic oil 2%; Elasticizer 2%; Plasticizer 2%; Nano calcium carbonate 0.5%; Silicone acrylic emulsion 0.5%.

[0008] Furthermore, the modifier is a mixed reactant of SBR and a polymer resin.

[0009] Furthermore, the modifier is a mixed reactant of SBS and EPDM.

[0010] Furthermore, the elasticizer is at least one of styrene-butadiene rubber, nitrile-butadiene rubber, polyvinyl chloride, polypropylene and ethylene-vinyl acetate copolymer.

[0011] Furthermore, the plasticizer is at least one of phthalate, dioctyl phthalate, and dibutyl phthalate.

[0012] A method for preparing a composite modified asphalt comprises the following steps: S1: mixing a temperature-resistant modifier; mixing SBR with a polymer resin or SBS with EPDM to prepare a temperature-resistant modifier; S2: heating the base asphalt at a temperature between 150° and 180°, and adding the remaining raw materials in sequence; S3: The mixture is sheared by a high-speed shearing machine at a shear rate of 6000r / min-8000r / min, so that the remaining raw materials are evenly dispersed in the matrix asphalt; S4: Development, so that the raw materials and the matrix asphalt can fully react and fuse; S5: Take samples and conduct performance testing.

[0013] Furthermore, in S2, the raw materials are added into the base asphalt by adopting the principle of small amounts and multiple times.

[0014] Furthermore, in S4, the development can be achieved by any one of static development, low-speed stirring development, cyclic heating development and ultrasound-assisted development.

[0015] At least one of the above technical solutions adopted in the embodiments of the present invention can achieve the following beneficial effects: The present invention adopts a high temperature resistant modifier made of a mixed reactant of SBR and a polymer resin or a low temperature resistant modifier made of a mixed reactant of SBS and EPDM, so that the high temperature resistance and low temperature resistance of asphalt are improved, the tolerance temperature of asphalt is increased, the bearing capacity of asphalt pavement is increased, the use effect and service life of asphalt pavement are improved, and the asphalt pavement is suitable for targeted selection and use in some cold or high temperature areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 It is a flow chart of the preparation process of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] The technical solutions provided by various embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0019] The embodiment of the present invention provides a composite modified asphalt, wherein the modified asphalt is composed of the following components in percentage by mass: Matrix asphalt 70%-80%, temperature resistance modifier 10%-15%, hydrated silicon dioxide 5%-8%, aromatic oil 1%-3%, elasticizer 1%-3%, plasticizer 1%-3%, nano calcium carbonate 0.2%-0.8%, silicone acrylic emulsion 0.1%-1%;

[0020] Wherein, the modified asphalt is preferably composed of the following components in percentage by mass: Base asphalt 75%, temperature resistance modifier 12%, hydrated silicon dioxide 6%, aromatic oil 2%, elasticizer 2%, plasticizer 2%, nano calcium carbonate 0.5%, silicone acrylic emulsion 0.5%; Specifically, since hydrated silicon dioxide is a porous, granular or blocky silicate material obtained by the reaction of silica and alkali, which contains many tiny pores, these pores provide a huge surface area, making it adsorbent and dry, which can enhance the deformation resistance of asphalt at high temperatures and reduce the occurrence of rutting. It can also be combined with other auxiliary materials to make the structure more solid and improve the overall performance of asphalt mixtures. The main components of aromatic components and colloids in aromatic oil can be added to molten asphalt to quickly combine with it, improve the asphalt components, and will not precipitate from the asphalt when the state changes. It can also promote the dissolution of polymer modifiers. When the base asphalt is too hard, the aromatic oil can also make it more emulsified. The elasticizer and plasticizer therein can increase the elasticity and plasticity of the asphalt, so that it can be deformed after being subjected to force. It can better restore the original state, improve the fatigue resistance of asphalt pavement, enhance the flexibility of asphalt at low temperature, reduce the risk of low temperature cracking, and delay the aging and hardening of asphalt during long-term use. Nano calcium carbonate is a calcium carbonate powder with a particle size at the nano level. It has a very high specific surface area and surface activity. It can change the viscosity of asphalt, making it more suitable for processing and construction. Due to its high hardness and wear resistance, it can improve the wear resistance of asphalt pavement. It is also a non-toxic, odorless, pollution-free environmentally friendly material, which improves the environmental protection effect. Silicone acrylic emulsion is an emulsion copolymerized by acrylic ester monomers and organic silicon compounds. It can enhance the UV resistance of asphalt, thereby slowing down the aging of asphalt, extending the service life of asphalt roads, improving the anti-skid performance of asphalt pavement, and improving driving safety.

[0021] Preferably, the modifier is a mixed reactant of SBR and a polymer resin. SBR is a commonly used synthetic rubber, which is copolymerized by styrene and butadiene and has good wear resistance and elasticity. When SBR is mixed with polymers such as PE, PP, etc., it can modify asphalt, increase the softening point of asphalt, and make asphalt less likely to deform at high temperatures, thereby enhancing the rutting resistance and fatigue resistance of the asphalt pavement, and is suitable for use in some areas with high temperatures and more ultraviolet rays all year round.

[0022] Preferably, the modifier is a mixed reactant of SBS and EPDM. SBS is a thermoplastic elastomer. After mixing with EPDM or natural rubber, it can improve the toughness of asphalt under low temperature conditions, reduce the tendency of low temperature cracking, and improve the cold resistance of the road. It is suitable for use in some relatively cold areas.

[0023] Preferably, the elasticizer is at least one of styrene-butadiene rubber, nitrile rubber, polyvinyl chloride, polypropylene and ethylene-vinyl acetate copolymer to improve the overall strength and durability of the asphalt mixture, and can restore the original shape after deformation to enhance the fatigue resistance of the road surface.

[0024] Preferably, the plasticizer is at least one of phthalates, dioctyl phthalate, and dibutyl phthalate, which can reduce the viscosity of asphalt, make the asphalt softer, and improve its ability to withstand stretching without breaking, thereby making it easier to mix and process. It can also improve the flexibility of asphalt under low temperature conditions and reduce the risk of low temperature cracking.

[0025] A method for preparing a composite modified asphalt comprises the following steps: S1: mixing a temperature-resistant modifier; mixing SBR with a polymer resin or SBS with EPDM to prepare a temperature-resistant modifier; S2: heating the base asphalt at a temperature between 150° and 180°, and adding the remaining raw materials in sequence; S3: The mixture is sheared by a high-speed shearing machine at a shear rate of 6000r / min-8000r / min, so that the remaining raw materials are evenly dispersed in the matrix asphalt; S4: Development, so that the raw materials and the matrix asphalt can fully react and fuse; S5: Take samples and conduct performance testing.

[0026] Preferably, in S2, by adding the raw materials into the base asphalt in small amounts and multiple times, the modifier can be more evenly dispersed in the asphalt. A large amount of one-time addition may cause local agglomeration of the modifier, making it difficult to fully mix and affect the modification effect, while helping to more accurately control the progress of the modification reaction.

[0027] Preferably, in S4, the development can be achieved by any one of static development, low-speed stirring development, cyclic heating development and ultrasonic-assisted development. Static development is to place the sheared or stirred mixture in a constant temperature container and let it stand for a period of time at a specified temperature to allow the modifier and asphalt to react and fuse naturally. Low-speed stirring development is to continuously stir the mixture at a relatively low stirring speed to promote reaction and fusion, while avoiding excessive stirring to destroy the formed structure. Circulating heating development is to use a circulating heating system to periodically heat and cool the mixture within a specific temperature range, which helps to improve the dispersion and fusion effect of the modifier in the asphalt. Ultrasonic-assisted development uses the cavitation effect and mechanical vibration of ultrasound to accelerate the molecular diffusion and interaction between the modifier and the asphalt. In the actual preparation process, any method can be selected for processing.

[0028] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A composite modified asphalt, characterized in that: The modified asphalt is composed of the following components in percentage by mass: Base asphalt 70%-80%; Temperature resistance modifier 10%-15%; Hydrated silicon dioxide 5%-8%; Aromatic oil 1%-3%; Elasticizer 1%-3%; Plasticizer 1%-3%; Nano calcium carbonate 0.2%-0.8%; Silicone acrylic emulsion 0.1%-1%.

2. A composite modified asphalt according to claim 1, characterized in that: Preferably, the modified asphalt is composed of the following components in percentage by mass: Base asphalt 75%; Temperature resistance modifier 12%; Hydrated silicon dioxide 6%; Aromatic oil 2%; Elasticizer 2%; Plasticizer 2%; Nano calcium carbonate 0.5%; Silicone acrylic emulsion 0.5%.

3. A composite modified asphalt according to claim 1, characterized in that: The modifier is a mixed reactant of SBR and polymer resin.

4. The composite modified asphalt according to claim 1, characterized in that: The modifier is a mixed reactant of SBS and EPDM.

5. The composite modified asphalt according to claim 1, characterized in that: The elasticizer is at least one of styrene-butadiene rubber, nitrile-butadiene rubber, polyvinyl chloride, polypropylene and ethylene-vinyl acetate copolymer.

6. The composite modified asphalt according to claim 1, characterized in that: The plasticizer is at least one of phthalate, dioctyl phthalate and dibutyl phthalate.

7. A method for preparing the composite modified asphalt according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: mixing a temperature-resistant modifier; mixing SBR with a polymer resin or SBS with EPDM to prepare a temperature-resistant modifier; S2: heating the base asphalt at a temperature between 150° and 180°, and adding the remaining raw materials in sequence; S3: The mixture is sheared by a high-speed shearing machine at a shear rate of 6000r / min-8000r / min, so that the remaining raw materials are evenly dispersed in the matrix asphalt; S4: Development, so that the raw materials and the matrix asphalt can fully react and fuse; S5: Take samples and conduct performance testing.

8. The method for preparing a composite modified asphalt according to claim 7, characterized in that: In S2, the raw materials are added into the base asphalt by adopting the principle of small amounts and multiple times.

9. The method for preparing a composite modified asphalt according to claim 7, characterized in that: In S4, the development can be achieved by any one of static development, low-speed stirring development, cyclic heating development and ultrasound-assisted development.

Images