SBS modified asphalt and preparation method thereof

Abstract

The invention relates to the technical field of preparation of modified asphalt, in particular to SBS modified asphalt and a preparation method thereof. The SBS modified asphalt provided by the invention is prepared from the following raw materials: matrix asphalt, a linear SBS modifier 791H, a star SBS modifier 4306 and an auxiliary agent, the auxiliary agent is selected from one or two of aromatic oil, naphtha, a stabilizer and furfural extract oil. The modified asphalt prepared by the invention has high storage stability and ageing resistance, the high-temperature performance and water stability are remarkably improved, and the overall performance is better than that of linear SBS modified asphalt. According to the high-stability SBS modified asphalt disclosed by the invention, the storage stability problem is solved, various properties and pavement performance of the SBS modified asphalt are integrally improved, and the high-stability SBS modified asphalt is simple and convenient to prepare, short in processing flow, simple in equipment, mild in process condition, rapid in production and low in modification cost.

Description

Technical Field

[0001] The invention relates to the technical field of modified asphalt preparation, in particular to an SBS modified asphalt and a preparation method thereof. Background Art

[0002] Polymer modifiers are divided into four categories: rubber, thermoplastic elastomer, plastic and others. Among them, other categories mainly include fibers, anti-extraction agents such as polyamines, etc. Polymers can be dispersed in molten asphalt by physical methods such as stirring and grinding. Commonly used polymer modifiers include elastomers such as SBS, SIS, SE / BS, SBR, and plasticizers such as EVA, PE, APP, EPDM. Among them, SBS stands for thermoplastic elastomer polystyrene-polybutadiene-polystyrene triblock copolymer. The SBS modified asphalt obtained by using SBS modifier has good high and low temperature performance and a wide operating temperature range. It is currently the most widely used polymer modifier at home and abroad.

[0003] Due to the differences in relative molecular mass, chemical structure and composition between asphalt and SBS, SBS is distributed in the asphalt medium as fine particles, presenting a two-phase structure, and thus has poor high-temperature storage stability. SBS can be divided into linear and star-shaped according to different structures. The effects of star-shaped and linear SBS on the properties of modified asphalt are also different. The star-shaped SBS has greater strength than the linear type, has a better modification effect on asphalt, has a greater increase in softening point, and has good high-temperature performance, but its low-temperature ductility is lower than that of linear SBS modified asphalt.

[0004] In actual engineering applications, although SBS modified asphalt is qualified when transported to the construction site, it is prone to performance degradation during storage at the construction site. This is mainly because the existing SBS modified asphalt uses linear SBS as a modifier. However, linear SBS has poor thermal stability. There is active hydrogen in its SBS molecular structure, which is very easy to break during high-temperature thermal storage, resulting in serious degradation of its modified asphalt performance. In fact, the unstable phase structure of linear SBS modified asphalt is the root cause of its rheological performance degradation during storage and transportation. The existing technology uses star-shaped SBS modifiers, but star-shaped SBS has poor compatibility with asphalt, and the modified asphalt cannot be stored for a long time. Summary of the invention

[0005] In view of this, the technical problem to be solved by the present invention is an SBS modified asphalt and a preparation method thereof. The SBS modified asphalt provided by the present invention has both high storage stability and anti-aging performance.

[0006] The SBS modified asphalt of the present invention is obtained from raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and additives;

[0007] The auxiliary agent is selected from one or two of aromatic oil, naphtha, stabilizer and furfural extracted oil.

[0008] The inventors of the present application creatively discovered that when linear SBS modifier 791H and star-shaped SBS modifier 4306 are used together in the modification of base asphalt, the resulting SBS modified asphalt not only has the same or even slightly better needle penetration, softening point and high and low temperature ductility as the existing SBS modified asphalt obtained by using a single linear SBS modifier, but also has high storage stability and anti-aging properties.

[0009] The linear SBS modifier 791H and the star-shaped SBS modifier 4306 of the present invention play the role of SBS modifiers together. In the mixture of two SBSs with different structures, the total molecular weight of the linear SBS modifier 791H and the star-shaped SBS modifier 4306 is 50,000 to 150,000; the total content of styrene structural units in the linear SBS modifier 791H and the star-shaped SBS modifier 4306 is 20% to 45%. In certain embodiments of the present invention, the star-shaped SBS modifier 4306 accounts for 5% to 20% of the total mass of the linear SBS modifier 791H and the star-shaped SBS modifier 4306.

[0010] The SBS modified asphalt of the present invention is obtained from raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and auxiliary agents. The auxiliary agent of the present invention is preferably selected from aromatic oil and stabilizer. The base asphalt of the present invention is No. 70 petroleum asphalt, preferably No. 70 Class A road petroleum asphalt. Wherein, the total mass of the linear SBS modifier 791H and the star-shaped SBS modifier 4306 accounts for 3% to 6% of the base asphalt. The mass proportion of the auxiliary agent in the base asphalt is 0.2% to 3%.

[0011] The present invention also provides a method for preparing the SBS modified asphalt described in any of the above technical solutions, comprising the following steps: mixing raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and auxiliary agents, and developing them to obtain SBS modified asphalt. Specifically, the present invention first mixes base asphalt, linear SBS modifier 791H and star-shaped SBS modifier 4306, then adds auxiliary agents thereto, and develops them to obtain SBS modified asphalt.

[0012] The mixing of the present invention is carried out at a temperature of 170°C to 180°C for 10 min to 50 min, and the mixing is carried out at a rotation speed of 3000 rpm to 5000 rpm. The development of the present invention is carried out at a temperature of 160°C to 185°C for 80 min to 100 min, and the development is carried out at a rotation speed of 400 rpm to 800 rpm.

[0013] The present invention provides an SBS modified asphalt and a preparation method thereof. The SBS modified asphalt provided by the present invention is obtained from raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and additives. The modified asphalt prepared by the present invention has high storage stability and anti-aging performance at the same time, and the high temperature performance and water stability are significantly improved, and the overall performance is better than that of linear SBS modified asphalt. The high-stability SBS modified asphalt in the present invention not only solves the storage stability problem, but also improves the various properties and road performance of the SBS modified asphalt as a whole, and is easy to prepare, has a short processing flow, simple equipment, mild process conditions, rapid production and low modification cost. DETAILED DESCRIPTION

[0014] The present invention discloses an SBS modified asphalt and a preparation method thereof. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve the same. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are deemed to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0015] The raw material information used in the specific implementation mode of the present invention is as follows:

[0016] Linear SBS modifier 791H, supplier: Hainan Baling Chemical New Materials Co., Ltd.;

[0017] Star-shaped SBS modifier 4306, supplier: Hainan Baling Chemical New Materials Co., Ltd.;

[0018] Star-shaped SBS modifier 4301, supplier: Hainan Baling Chemical New Materials Co., Ltd.;

[0019] No. 70 Class A road petroleum asphalt, supplier: Jingbo (Hainan) New Materials Co., Ltd.;

[0020] The present invention will be further described below in conjunction with embodiments:

[0021] Example 1

[0022] Under normal pressure, 3.6% linear SBS modifier 791H, 0.4% star-shaped SBS modifier 4306 and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% aromatic oil and 0.25% stabilizer were added, and the mixture was stirred and developed at 185°C for 100 min to finally obtain the SBS modified asphalt product.

[0023] Example 2

[0024] Under normal pressure, 3.4% linear SBS modifier 791H, 0.6% star-shaped SBS modifier 4306 and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% aromatic oil and 0.25% stabilizer were added, and the mixture was stirred and developed at 185°C for 100 min to finally obtain the SBS modified asphalt product.

[0025] Example 3

[0026] Under normal pressure, 3.8% linear SBS modifier 791H, 0.2% star-shaped SBS modifier 4306 and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% aromatic oil and 0.25% stabilizer were added, and the mixture was stirred and developed at 185°C for 100 min to finally obtain SBS modified asphalt product.

[0027] Comparative Example 1

[0028] Under normal pressure, 3.8% linear SBS modifier 791H, 0.2% star-shaped SBS modifier 4306 and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% wax oil and 0.25% stabilizer were added, and the mixture was stirred and developed at 185°C for 100 min to finally obtain the SBS modified asphalt product.

[0029] Comparative Example 2

[0030] Under normal pressure, 3.8% linear SBS modifier 791H, 0.2% star-shaped SBS modifier 4301 and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% aromatic oil and 0.25% stabilizer were added, and the mixture was stirred and developed at 185°C for 100 min to finally obtain the SBS modified asphalt product.

[0031] Comparative Example 3

[0032] Under normal pressure, 4% linear SBS modifier 791H and 70#A grade road petroleum asphalt were mixed at 175°C for 45 min by high-speed shear mixing equipment, and then 1.3% aromatic oil and 0.25% stabilizer were added, and stirred at 185°C for 100 min to finally obtain SBS modified asphalt product.

[0033] The asphalt products obtained in Examples 1-4 and Comparative Examples 1-2 were tested, and the test results are shown in Table 1.

[0034] Table 1

[0035]

[0036] As can be seen from Table 1, the SBS modified asphalts of Examples 1 to 3 have a low 48 h softening point difference and a high residual 5° C. elongation, indicating that they have both good storage stability and anti-aging properties.

[0037] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A SBS modified asphalt, characterized in that: It is obtained from raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and additives; The auxiliary agent is selected from one or two of aromatic oil, naphtha, stabilizer and furfural extracted oil.

2. The SBS modified asphalt according to claim 1, characterized in that The total molecular weight of the linear SBS modifier 791H and the star-shaped SBS modifier 4306 is 50,000 to 150,000; The total content of styrene structural units in the linear SBS modifier 791H and the star-shaped SBS modifier 4306 is 20% to 45%.

3. The SBS modified asphalt according to claim 1, characterized in that The star-shaped SBS modifier 4306 accounts for 5% to 20% of the total mass of the linear SBS modifier 791H and the star-shaped SBS modifier 4306.

4. The SBS modified asphalt according to claim 1, characterized in that The total mass of the linear SBS modifier 791H and the star-shaped SBS modifier 4306 in the base asphalt accounts for 3% to 6%.

5. The SBS modified asphalt according to any one of claims 1 to 4, characterized in that: The mass proportion of the additive in the base asphalt is 0.2% to 3%.

6. The SBS modified asphalt according to any one of claims 1 to 4, characterized in that: The auxiliary agent is selected from aromatic oil and stabilizer.

7. The SBS modified asphalt according to any one of claims 1 to 4, characterized in that: The base asphalt is No. 70 petroleum asphalt.

8. The method for preparing the SBS modified asphalt according to any one of claims 1 to 7, characterized in that: The following steps are involved: The raw materials including base asphalt, linear SBS modifier 791H, star-shaped SBS modifier 4306 and additives are mixed and developed to obtain SBS modified asphalt.

9. The preparation method according to claim 8, characterized in that: The mixing is performed at a temperature of 170° C. to 180° C. for 10 min to 50 min.

10. The preparation method according to claim 8, characterized in that: The development is carried out at a temperature of 160°C to 185°C for 80 min to 100 min.

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