KR102133192B1 - Modified asphalt composition and method for preparing modified asphalt - Google Patents

Abstract

The present invention relates to a modified asphalt composition having excellent storage stability and improved high temperature properties and a method for manufacturing the modified asphalt composition.
Modified asphalt composition according to the present invention comprises an asphalt mixture comprising VTB (Vacuum Tower Bottom); Modifiers; Crosslinking agents; And by containing 8 to 40 parts by weight of the VTB based on 100 parts by weight of the asphalt mixture, phase separation of the asphalt material does not occur during storage of the asphalt, and provides a modified asphalt composition having improved high-temperature properties and a method for manufacturing the asphalt.

Description

Modified asphalt composition and its manufacturing method {MODIFIED ASPHALT COMPOSITION AND METHOD FOR PREPARING MODIFIED ASPHALT}

The present invention relates to a modified asphalt composition having excellent storage stability and improved high temperature properties and a method for manufacturing the modified asphalt composition.

Asphalt is black at room temperature and is a highly viscous material in a sticky semi-solid state. Asphalt is rich in plasticity, has great waterproofness, electrical insulation, and adhesiveness, and has chemically stable properties, so it is used in various fields such as road pavement, waterproofing materials, adhesives, etc. In addition, in order to further improve the performance of the asphalt, many studies have been made and commercialized for the modified asphalt to which a modifier is added.

Specifically, a polymer is used as a modifier on asphalt. Polymers used as asphalt modifiers include, for example, low density polyethylene, ethylene vinyl acetate, styrene-butadiene rubber, butyl rubber, and the like. Vinyl aromatic hydrocarbon-conjugated diene block copolymers, such as styrene-butadiene-styrene (SBS) block copolymers, are widely used as modifiers to improve the properties of asphalt compositions.

However, since the vinyl aromatic hydrocarbon-conjugated diene block copolymer has little affinity with asphalt, there is a problem that phase separation of the asphalt material occurs during storage. In addition, conventional asphalt has a problem that deformation due to ductility at high temperatures in the summer.

An object of the present invention is to provide a modified asphalt composition for improving the high temperature properties of asphalt and a method for manufacturing the same.

In addition, an object of the present invention is to provide a modified asphalt composition that does not cause phase separation of the asphalt material during storage of the asphalt and a method for manufacturing the same.

To provide a modified asphalt composition having excellent storage stability of asphalt and improving high temperature properties, the modified asphalt composition according to the present invention includes an asphalt mixture comprising VTB (Vacuum Tower Bottom); Modifiers; Crosslinking agents; And 8 to 40 parts by weight of the VTB based on 100 parts by weight of the asphalt mixture.

In addition, in order to provide a method for preparing a modified asphalt composition having excellent storage stability of asphalt and improving high temperature properties, the method for preparing a modified asphalt composition according to the present invention is (a) VTB (Vacuum Tower) based on 100 parts by weight of the asphalt mixture. Bottom) heating the asphalt mixture containing 8 to 40 parts by weight until reaching 160 to 180° C. to obtain a heated asphalt mixture; (b) adding and mixing a modifier containing a styrene-butadiene-styrene block copolymer (SBS) to the heated asphalt mixture; (c) stirring the modifier containing the heated asphalt mixture and the styrene-butadiene-styrene block copolymer (SBS) for 2 hours to obtain a first mixture; (d) adding a crosslinking agent containing at least one of phenolic resin, sulfur, and benzenesulfonate to the first mixture to obtain a second mixture; And (e) stirring the second mixture for 2 hours; It includes.

Modified asphalt composition according to the present invention comprises an asphalt mixture comprising VTB (Vacuum Tower Bottom); Modifiers; Crosslinking agents; And by containing the VTB 8 to 40 parts by weight based on 100 parts by weight of the asphalt mixture, the storage stability of the asphalt is excellent, there is an effect of improving the high-temperature properties.

In addition, the method for preparing a modified asphalt composition according to the present invention (a) heating the asphalt mixture containing 8 to 40 parts by weight of VTB (Vacuum Tower Bottom) based on 100 parts by weight of the asphalt mixture until it reaches 160 to 180°C. To obtain a heated asphalt mixture; (b) adding and mixing a modifier containing a styrene-butadiene-styrene block copolymer (SBS) to the heated asphalt mixture; (c) stirring the modifier containing the heated asphalt mixture and the styrene-butadiene-styrene block copolymer (SBS) for 2 hours to obtain a first mixture; (d) adding a crosslinking agent containing at least one of phenolic resin, sulfur, and benzenesulfonate to the first mixture to obtain a second mixture; And (e) stirring the second mixture for 2 hours; By containing the excellent storage stability of the asphalt, there is an effect of improving the high-temperature properties.

Furthermore, the modified asphalt composition according to the present invention has an excellent economic effect by utilizing a large amount of VTB (Vacuum Tower Bottom), which is a remnant after refining in a vacuum residue hydrocracker (Vacuum Residue Hydrocracker).

The above-described objects, features, and advantages will be described in detail below, and accordingly, a person skilled in the art to which the present invention pertains can easily implement the technical spirit of the present invention. In the description of the present invention, when it is determined that detailed descriptions of known technologies related to the present invention may unnecessarily obscure the subject matter of the present invention, detailed descriptions will be omitted. Hereinafter, a preferred embodiment according to the present invention will be described in detail.

The present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete and the scope of the invention to those skilled in the art. It is provided to inform. Hereinafter, the present invention will improve the high-temperature properties of asphalt, phase separation of the asphalt material does not occur during storage of the asphalt, economically excellent modified asphalt composition and a method of manufacturing the same will be described in detail.

<Modified asphalt composition>

Modified asphalt composition according to the present invention comprises an asphalt mixture comprising VTB (Vacuum Tower Bottom); Modifiers; Crosslinking agents; And 8 to 40 parts by weight of the VTB based on 100 parts by weight of the asphalt mixture.

In addition, the modified asphalt composition according to the present invention may include a vacuum residue (Vacuum Residue) and heavy vacuum gas oil (Heavy Vacuum Gas Oil).

The reduced pressure residue (Vacuum Residue) refers to an oil residue that is left after refining crude oil and is not distilled any more under the reduced pressure distillation process. The vacuum residue (Vacuum Residue) is used as a feed of the vacuum residue hydrocracking process (Vacuum Residue Hydrocracker). In particular, the reduced pressure residue (Vacuum Residue) is mixed with crushed stone, sand, stone powder and the like to form an asphalt material.

The heavy vacuum gas oil is a remnant after refining crude oil and refers to an oil having a high specific gravity and boiling point among vacuum gas oil produced in a vacuum distillation process. The heavy vacuum gas oil is used as a raw material for a lubricating base oil or used as a feed for a vacuum residue hydrocracking process (Vacuum Residue Hydrocracker). In particular, it is used to adjust the viscosity of asphalt.

In addition, the modified asphalt composition according to the present invention comprises 8 to 40 parts by weight of the VTB (Vacuum Tower Bottom) based on 100 parts by weight of the asphalt mixture. The VTB (Vacuum Tower Bottom) refers to an oil residue that has not been further distilled in a vacuum residue hydrocracker (Vacuum Residue Hydrocracker). Preferably, the modified asphalt composition according to the present invention may contain 15 to 30 parts by weight of the VTB (Vacuum Tower Bottom) based on 100 parts by weight of the asphalt mixture. More preferably, the modified asphalt composition according to the present invention may contain the VTB (Vacuum Tower Bottom) in the range of 18 to 22 parts by weight based on 100 parts by weight of the asphalt mixture. When the content of the VTB (Vacuum Tower Bottom) exceeds 40 parts by weight, aging of the asphalt proceeds due to an oxidation reaction, which may cause a problem that the viscosity of the asphalt is lowered. In addition, if the content of the VTB (Vacuum Tower Bottom) exceeds 40 parts by weight, a low temperature crack may occur in winter and a plasticity change due to lack of heat resistance in summer. If the content of the VTB (Vacuum Tower Bottom) is less than 8 parts by weight, it is not commercially desirable due to the cost increase of the product.

The modified asphalt composition according to the invention comprises a modifier. The modifier may include styrene-butadiene-styrene block copolymer (SBS). Styrene-butadiene-styrene block copolymer (SBS) is a representative rubber modifier. When the styrene-butadiene-styrene block copolymer (SBS) is added to a hot asphalt mixture, styrene-butadiene-styrene block copolymer (SBS) is swelled. By being dispersed and swelling, the overall physical properties of the asphalt are improved.

The modified asphalt composition according to the invention comprises a crosslinking agent. The crosslinking agent serves to increase the softening point of the modified asphalt composition and improve compatibility and heat aging resistance during storage. The crosslinking agent may include at least one of phenolic resin, sulfur, and benzenesulfonate. Preferably, the crosslinking agent may include a phenolic resin, sulfur, and benzenesulfonate. The phenolic resin imparts tack to the modified asphalt composition. Examples of the sulfur include sulfur and sulfur compounds. Moreover, the said benzene sulfonate is an alkali benzene sulfonate, for example.

Modified asphalt composition according to the present invention is 94 to 99% by weight of the asphalt mixture; 0.1 to 5% by weight modifier; And 0.1 to 1% by weight of a crosslinking agent; may be included. Preferably, the modified asphalt composition is 95.5 to 97.5% by weight of the asphalt mixture; 2-4% by weight modifier; And 0.1 to 0.3% by weight of a crosslinking agent; may be included.

If the asphalt mixture is more than 99% by weight, or less than 94% by weight, there may be a problem that the road pavement is less resistant to plastic deformation. When the modifier exceeds 5% by weight, the manufacturing cost of the modified asphalt increases, which is uneconomical, and has high viscosity properties, resulting in low productivity in the production of modified asphalt and difficulty in uniform dispersion. If the modifier is less than 0.1% by weight, the modification effect of asphalt may be lowered. When the crosslinking agent exceeds 1% by weight, a problem that is vulnerable to low temperature cracking may occur due to excessive viscosity increase. If the crosslinking agent is less than 0.1% by weight, the role as a crosslinking agent is negligible.

The modified asphalt composition according to the present invention may have a viscosity of 0.80 to 1.90 Pa·s at 135°C. Preferably, the modified asphalt composition may have a viscosity of 0.80 to 1.85 Pa·s at 135°C. Viscosity was measured according to ASTM D4402 under the condition of spindle 27 using a Brookfield DV-II+ Pro Model. When the viscosity of the modified asphalt composition exceeds 1.90 Pa·s at 135° C., there may be a problem that workability is deteriorated when manufacturing the modified asphalt. When the modified asphalt composition has a viscosity of less than 0.80 Pa·s at 135° C., there may be a problem that physical properties against low temperature are deteriorated.

The modified asphalt composition according to the present invention is characterized by being a premix type. The manufacturing method of modified asphalt can be roughly divided into a premix type and a plant mix type. The plant mix type has a problem in that workability is greatly deteriorated because each of asphalt and modifier must be added to the mixer at a certain weight ratio. Since the modified asphalt composition according to the present invention is manufactured by melt-mixing asphalt and a modifier, mass production is possible. In addition, the modified asphalt composition according to the present invention has an advantage that phase separation of the asphalt material does not occur even by the premix type.

<Method for manufacturing modified asphalt composition>

Next, the method for producing a modified asphalt composition according to the present invention (a) 100 parts by weight of asphalt mixture based on VTB (Vacuum Tower Bottom) 8 to 40 parts by weight of the asphalt mixture containing until reaching 160 to 180 ℃ Heating to obtain a heated asphalt mixture; (b) adding and mixing a modifier containing a styrene-butadiene-styrene block copolymer (SBS) to the heated asphalt mixture; (c) stirring the modifier containing the heated asphalt mixture and the styrene-butadiene-styrene block copolymer (SBS) for 2 hours to obtain a first mixture; (d) adding a crosslinking agent containing at least one of phenolic resin, sulfur, and benzenesulfonate to the first mixture to obtain a second mixture; And (e) stirring the second mixture for 2 hours; It includes.

The asphalt mixture of step (a) may include a vacuum residue (Vacuum Residue) and heavy vacuum gas oil (Heavy Vacuum Gas Oil). Preferably, 15 to 30 parts by weight of VTB (Vacuum Tower Bottom) based on 100 parts by weight of the asphalt mixture in step (a) may be included.

In step (b), after adding a modifier containing styrene-butadiene-styrene block copolymer (SBS) to the heated asphalt mixture, the dispersion state of the styrene-butadiene-styrene block copolymer (SBS) is changed to a fluorescent microscope. Can be observed. In addition, in step (c), the heated asphalt mixture and the modifier containing the styrene-butadiene-styrene block copolymer (SBS) may be stirred for 2 hours with a high shear mixer. Preferably, the modified asphalt composition prepared according to the method of the present invention comprises 94 to 99% by weight of the asphalt mixture; 0.1 to 5% by weight of the modifier; And 0.1 to 1% by weight of the crosslinking agent; may be included.

Hereinafter, a specific aspect of the present invention will be described through examples.

<Example>

<Preparation of modified asphalt composition>

A modified asphalt composition having a composition ratio shown in Table 1 below was prepared.

The asphalt mixture was heated and heated to 180°C. Styrene-butadiene-styrene block copolymer (SBS) was added to the asphalt mixture in the heated state to mix, and the dispersion state of styrene-butadiene-styrene block copolymer (SBS) was observed with a fluorescence microscope for 2 hours with a high shear mixer. While stirring, the temperature was maintained until the styrene-butadiene-styrene block copolymer (SBS) was completely melted. To the mixture, phenol resin, sulfur, and alkylbenzenesulfonate were added and mixed, followed by stirring with a high shear mixer for 2 hours. Then, it was cooled to room temperature to obtain a modified asphalt composition.

In addition, the styrene-butadiene-styrene block copolymer (SBS) modifier used in this example and the comparative example used Luprene from LG Chem.

ingredient
(weight%) Example Comparative example One 2 3 4 One 2 As
Palt
mixture Decompression
Residue 74.50 65.80 57.45 49.09 57.63 83.52 Heavy
Decompression 12.92 13.40 13.63 13.88 13.67 12.48 VTB 8.28 16.50 24.62 32.73 24.70 - Modifier SBS 4.00 4.00 4.00 4.00 4.00 4.00 Crosslinker 0.3 0.3 0.3 0.3 - -

<Experimental Example>

The modified asphalt compositions prepared in Examples and Comparative Examples were measured as follows and the results are shown in Tables 2 and 3.

1. Commonality evaluation

The modified asphalt composition was evaluated based on the PG test. Before and after RTFO (Rolling Thin Film Oven, Thin Film Heating Test) by the PG evaluation method, the high-temperature grade was evaluated by DSR and the results are shown in Table 2.

-G ^* /sinδ in Table 2 below refers to the factors related to plastic deformation resistance of asphalt, and if it is 1.0 or higher before RTFO and 2.2 or higher after RTFO, it satisfies the high temperature common grade at the corresponding temperature.

PG high temperature rating High temperature rating evaluation RTFO I After RTFO G*/sinδ
(64℃, kPa) G*/sinδ
(70℃, kPa) G*/sinδ
(76℃, kPa) G*/sinδ
(64℃, kPa) G*/sinδ
(70℃, kPa) G*/sinδ
(76℃, kPa) Example 1 76 - - 1.64 - - 2.43 Example 2 76 - - 1.60 - - 2.53 Example 3 76 - - 1.62 - - 2.67 Example 4 76 - - 1.61 - - 2.99 Comparative Example 1 76 - - 1.60 - - 2.65 Comparative Example 2 76 - - 1.61 - - 2.34

According to Table 2, it can be seen that the modified asphalt compositions of Examples 1 to 4 have improved high temperature properties compared to Comparative Example 2 without VTB. Through the examples and comparative examples, it can be seen that a difference occurs in improving the high-temperature properties of asphalt according to the VTB content.

2. Storage stability evaluation

The modified asphalt composition heated to 180° C. was stored in a tube having a length of 14 cm and a diameter of 2.5 cm and stored at 163° C. for 48 hours. After 48 hours elapsed, the modified asphalt composition in the tube was cured to a room temperature of 25° C. or less, and then the softening point was measured. If the difference in softening point between the upper part and the lower part was 2.2°C or lower, the result was determined as pass, and if it exceeded 2.2°C, it was judged as rejected and the results are shown in Table 3.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Difference in softening point between upper part and lower part (℃) 1.4 1.4 1.5 1.5 30 29 Storage stability pass pass pass pass fail fail

According to Table 3, it can be seen that the modified asphalt compositions of Examples 1 to 4 have better storage stability than the modified asphalt compositions of Comparative Examples 1 and 2. In Comparative Examples 1 and 2, the crosslinking agent was not included. Accordingly, the modified asphalt compositions of Comparative Examples 1 and 2 did not satisfy the storage stability evaluation criteria due to reduced viscosity. Through the examples and comparative examples, it can be seen that a difference occurs in storage stability of the modified asphalt composition depending on whether a crosslinking agent is included.

Although the present invention has been described as described above, it is obvious that the present invention is not limited by the embodiments disclosed herein, and that various modifications can be made by those skilled in the art within the scope of the technical idea of the present invention. In addition, although the operation and effect according to the configuration of the present invention is not explicitly described while describing the embodiments of the present invention, it is natural that the predictable effect by the configuration should also be recognized.

Claims (9)

An asphalt mixture comprising a vacuum tower bottom (VTB), which is the oil remaining after purification in a vacuum residue hydrocracker (Vacuum Residue Hydrocracker);
Modifiers;
Crosslinking agents; And
8 to 40 parts by weight of the VTB based on 100 parts by weight of the asphalt mixture
Modified asphalt composition.
According to claim 1,
The asphalt mixture
Containing Vacuum Residue and Heavy Vacuum Gas Oil
Modified asphalt composition.
According to claim 1,
94 to 99% by weight of the asphalt mixture;
0.1 to 5% by weight of the modifier; And
0.1 to 1% by weight of the crosslinking agent; Containing
Modified asphalt composition.
According to claim 1,
The modifier comprises a styrene-butadiene-styrene block copolymer (SBS)
Modified asphalt composition.
According to claim 1,
The crosslinking agent contains at least one of phenolic resin, sulfur, and benzenesulfonate
Modified asphalt composition.
According to claim 1,
The modified asphalt composition is characterized in that the viscosity at 135 ℃ 0.80 ~ 1.90Pa·s
Modified asphalt composition.
The method according to any one of claims 1 to 6,
The modified asphalt composition is characterized in that the premix type
Modified asphalt composition.
(a) heating the asphalt mixture containing 8 to 40 parts by weight of VTB (Vacuum Tower Bottom) based on 100 parts by weight of the asphalt mixture until reaching 160 to 180° C. to obtain a heated asphalt mixture;
(b) adding and mixing a modifier containing a styrene-butadiene-styrene block copolymer (SBS) to the heated asphalt mixture;
(c) stirring the modifier containing the heated asphalt mixture and the styrene-butadiene-styrene block copolymer (SBS) for 2 hours to obtain a first mixture;
(d) adding a crosslinking agent containing at least one of phenolic resin, sulfur, and benzenesulfonate to the first mixture to obtain a second mixture; And
(e) stirring the second mixture for 2 hours; Manufacturing modified asphalt, including
Method for manufacturing modified asphalt composition.
The method of claim 8,
The asphalt mixture of step (a) is
Containing Vacuum Residue and Heavy Vacuum Gas Oil
Method for manufacturing modified asphalt composition.