JPWO2020054168A1 - Asphalt composition and asphalt mixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for improving water resistance performance by suppressing peeling of asphalt.
The asphalt composition of the present disclosure contains at least an asphalt base oil and a silane-containing coupling agent, and the silane-containing coupling agent has a styrene-butadiene structure and the silane-containing coupling agent. The content of is characterized by being 1.5% by weight or more and 3.0% by weight or less. Further, the asphalt mixture of the present disclosure is characterized in that at least an aggregate is mixed with the asphalt composition.
[Selection diagram] None

Description

The present invention relates to an asphalt composition and an asphalt mixture that improve water resistance by suppressing peeling of asphalt.

In recent years, asphalt peeling phenomenon has come to be mentioned as a main cause of damage to asphalt pavement, in which rainwater or groundwater permeates between asphalt and aggregate and the asphalt coated on the surface of the aggregate peels off. rice field. When such an asphalt peeling phenomenon occurs, the function of adhering the aggregates to each other is deteriorated, and there is a possibility that damage such as cracks and potholes is likely to occur.

In response to the occurrence of such asphalt exfoliation phenomenon, resin acids such as dimer acid and rosin, saturated fatty acids such as stearic acid, palmitic acid and myristic acid, and unsaturated fatty acids such as oleic acid, linoleic acid and lysylenenic acid are not saturated. Methods for suppressing peeling of asphalt by mixing fatty acids such as fatty acids with asphalt as an anti-peeling agent have been studied (Patent Documents 1 and 2). However, despite the fact that anti-peeling agents such as resin acids and fatty acids are expensive, even if they are added in excess of a certain amount, a sufficient anti-peeling effect cannot be obtained especially for acid rocks such as granite. Therefore, even for these rocks, a technique for suppressing the exfoliation of asphalt is required.

Japanese Unexamined Patent Publication No. 2016-12320 Japanese Unexamined Patent Publication No. 2015-143340

Therefore, the present disclosure has been devised in view of the above points, and an object of the present disclosure is to provide a technique for improving water resistance performance by suppressing peeling of asphalt.

According to one aspect of the present disclosure, it contains at least an asphalt base oil and a silane-containing coupling agent, the silane-containing coupling agent has a styrene-butadiene structure, and the content of the silane-containing coupling agent. Can provide a technique characterized by being 1.5% by weight or more and 3.0% by weight or less.

According to the present disclosure, it is possible to provide a technique for improving water resistance performance by suppressing peeling of asphalt.

It is a figure which shows an example of the manufacturing process of the asphalt composition and the asphalt mixture material preferably used in this embodiment.

As described above, the present inventors have diligently studied the component composition of the asphalt composition and the asphalt mixture and the content thereof. As a result, they have newly found that a specific silane-containing coupling agent is added in order to improve the water resistance performance by suppressing the peeling of asphalt, and have completed the present invention. Hereinafter, embodiments of the asphalt composition and the asphalt mixture in the present embodiment will be described in detail.

The peeling resistance described below indicates the adhesiveness between the aggregate and the asphalt, and indicates that the asphalt is less likely to be peeled from the aggregate as the peeling resistance increases. ..

The asphalt composition in the present embodiment contains at least an asphalt base oil and a silane-containing coupling agent, respectively, and the silane-containing coupling agent has a styrene-butadiene structure. Further, the asphalt composition in the present invention may contain a styrene-butadiene-styrene copolymer (hereinafter referred to as SBS). Suitable contents and properties of each component composition are as follows.

Asphalt base oil: 90.0% by weight or more, 98.5% by weight or less SBS: 7.0% by weight or less Silane-containing coupling agent: 1.5% by weight or more, 3.0% by weight or less Average peeling rate of upper and lower surfaces : Less than 40%

Hereinafter, the details of each component composition and the reason for limiting the content thereof will be described.

(Asphalt base oil)
As the asphalt base oil, for example, solvent-free asphalt such as straight asphalt and propane-free asphalt, asphalt such as blown asphalt and semi-blown asphalt, or asphalt such as semi-blown asphalt are appropriately used. Further, it is more preferable that the asphalt base oil further contains an aromatic heavy mineral oil.

The content of the asphalt base oil with respect to the entire asphalt composition in the present embodiment is determined by the content of the silane-containing coupling agent and the content of SBS, and is 90.0% by weight or more and 98.5% by weight or less. Is preferable.

(Straight asphalt)
As the straight asphalt, the asphalt specified in JIS K 2207 or a mixture thereof can be used. In the present embodiment, this straight asphalt can be used from needle penetration grades 40 to 60 to 200 to 300 equivalent.

(Solvent-free asphalt)
Solvent-removing asphalt corresponds to the residue obtained by extracting solvent-removing oil (high-viscosity lubricating oil fraction) from vacuum-distilled residual oil (see "New Petroleum Dictionary", edited by the Petroleum Society, 1982, p.308). .. In particular, when propane or propane and butane are used as the solvent, it is called propane-free asphalt.

(Bloan asphalt)
Blone asphalt is, for example, asphalt defined in JIS K 2207.

(Semi-blown asphalt)
Semi-blown asphalt is, for example, "Asphalt Pavement Outline", published by Japan Road Association, January 13, 1997, p. 51, Semi-blown asphalt as defined in Table-3.3.4.

(Aromatic heavy mineral oil)
In the asphalt composition of the present embodiment, the aromatic heavy mineral oil is a solvent-removing oil obtained by removing the vacuum-distilled residual oil of crude oil with propane or the like, and further solvent-extracting the solvent-removing oil with a polar solvent such as furfural. By doing so, a solvent-extracted oil for obtaining bright stock (heavy lubricating oil), that is, an extract can be used. In particular, in the present embodiment, it is preferable to add an extract as an aromatic heavy mineral oil.

In the asphalt composition of the present embodiment, the role of the extract is to increase the solubility of the thermoplastic elastomer in the asphalt and prevent the occurrence of separation in the storage stability, and when the amount of the thermoplastic elastomer added is large, the extract is used. The amount of addition required is also increased. Further, if an extract more than necessary is added with respect to the amount of the thermoplastic elastomer added, the elastic modulus of the asphalt composition decreases.

The content of the extract in the entire asphalt composition in the present embodiment includes the degree of needle insertion, the softening point, the storage stability, the complex elastic modulus indicating the strength, the dynamic stability (DS) in the wheel tracking test, and the low temperature property. It is determined in consideration of the bending work amount and bending stiffness. In the range examined in the present embodiment, the content of the extract in the entire asphalt composition is preferably 2.0% by weight or more and 8.0% by weight or less, but the extract is contained. This is not particularly essential and may not be contained.

(SBS)
SBS is a thermoplastic elastomer added as a reinforcing material. The performance of SBS can be estimated mainly from its molecular weight and styrene content. The styrene content referred to here is the weight% of styrene contained in SBS.

Currently, the molecular weight of SBS, which is industrially easily available, is 120,000 or more and 250,000 or less. The styrene content of SBS is 25.0% by weight or more and 35.0% by weight or less, preferably 27.0% by weight or more and 33.0% by weight or less of the whole SBS.

In addition to the above, SBSs having different molecular weights and styrene contents are available, and the molecular weights of these SBSs are 80,000 or more and 90,000 or less. Further, the styrene content is 25.0% by weight or more and 50.0% by weight or less of the whole SBS.

It is not particularly essential that SBS is contained in the entire asphalt composition of the present embodiment, and it is not necessary that the asphalt composition is contained. However, in order to solve the above-mentioned problems, the asphalt composition of the present embodiment is used. The content of SBS in the whole product is preferably 7.0% by weight or less. By setting the SBS content to 7.0% by weight or less, the asphalt continuous phase can be maintained, and the water resistance of the dense particle size mixture having excellent water impermeability can be improved. On the other hand, when it is desired to produce an asphalt mixture having high drainage or water permeability in which voids are positively provided inside the pavement, the content of SBS in the entire asphalt composition of the present embodiment exceeds 7.0% by weight. By doing so, it is possible to produce an asphalt composition having high drainage or water permeability by causing a phase transition of SBS while solving the above-mentioned problems.

In the present embodiment, only one type of SBS may be mixed, or two or more types of SBS having a specific molecular structure may be selected and mixed. When only one type of SBS is mixed, it is possible to eliminate the complexity of selecting and mixing two or more types of SBS, and it is possible to reduce the manufacturing labor, which is preferable.

(Silane-containing coupling agent)
As the silane-containing coupling agent preferably used in the asphalt composition and the asphalt mixture of the present embodiment, for example, a silane-containing coupling agent represented by the following chemical formula (1) can be used.

・・・（１）

... (1)

The silane-containing coupling agent preferably used in the present embodiment has one organic functional group bonded to silicon and three hydrolyzing groups. The organic functional group in the silane-containing coupling agent comprises a styrene-butadiene structure and an ethylene structure. The styrene-butadiene structure is composed of a butadiene polymer having a degree of polymerization a and a styrene polymer having a degree of polymerization c (a and c are arbitrary positive numbers). The ethylene structure has an ethylene polymer having a degree of polymerization b bonded to silicon (b is an arbitrary positive number). R in the above chemical formula (1) represents a hydrolyzing group. The hydrolyzing group is, for example, a methoxy group or an ethoxy group.

Since the silane-containing coupling agent having the above-mentioned structure has a styrene-butadiene structure, it has a high affinity with asphalt, and since it has a hydrolyzing group, it has a binding force with an aggregate portion. Is high. Therefore, by adding a silane-containing coupling agent to the asphalt composition in the present embodiment, it is possible to improve the adhesiveness between the aggregate and the asphalt.

The silane-containing coupling agent preferably used in the present embodiment preferably has the following properties. For example, the viscosity at 25 ° C. is preferably 7,000 (mPa · sec) or more, and more preferably about 7,500 (mPa · sec) or more and 21,000 (mPa · sec) or less. Further, for example, it is preferable that the non-volatile content at a heating temperature of 105 ° C. and a heating time of 3 hours is more than 98%. Further, for example, the number average molecular weight calculated by styrene conversion is preferably 7,000 or more and 25,000 or less, and more preferably 9,000 or more and 9,500 or less.

The content of the silane-containing coupling agent in the entire asphalt composition of the present embodiment is 1.5% by weight or more and 3.0% by weight or less. Thereby, the peeling resistance can be improved. Therefore, the water resistance can be improved by suppressing the peeling of asphalt. On the other hand, when the content of the silane-containing coupling agent is less than 1.5% by weight, the peel resistance cannot be increased. Further, when the content of the silane-containing coupling agent exceeds 3.0% by weight, it cannot be mixed as an asphalt composition. Therefore, the content of the silane-containing coupling agent is 1.5% by weight or more and 3.0% by weight or less.

(Flash point of silane-containing coupling agent)
The flash point of the silane-containing coupling agent affects the safety during heating such as during production and storage. Since the silane-containing coupling agent preferably used in the present embodiment is added to, for example, asphalt base oil having a high temperature of 180 ° C. or higher, it is preferable to use one having a flash point of 250 ° C. or higher. When the flash point of the silane-containing coupling agent is 250 ° C. or higher, the safety during heating such as during production and storage can be further improved. Here, the flash point of the silane-containing coupling agent is measured by, for example, the method specified by JIS K 2207 “Petroleum asphalt-flash point test”.

(Peeling rate)
The asphalt composition of the present embodiment has an average peeling rate of less than 40% on the upper and lower surfaces. This makes it possible to obtain the desired peeling resistance. On the other hand, when the average peeling rate of the upper and lower surfaces is 40% or more, the desired peeling resistance cannot be obtained. As will be described later, the average peeling rate of the upper and lower surfaces is the test method (also referred to as boiling water peeling test, boiling water peeling test) specified in ASTM D3625 "Standard Practice for Effect of Water on Bitter on Bite Minous-Coated Aggregate Using Boiling Water". It is calculated by averaging the peeling area ratio of the upper surface of the specimen tested based on the boiling water peeling test) and the peeling area ratio of the lower surface.

(Evaporation mass change rate)
In the asphalt composition of the present embodiment, the rate of change in mass when the specimen was heated to 163 ° C. in air for 5 hours was measured, and the rate of change between the mass before heating and the mass after heating was measured. It is configured to be 1% or less. Preferably, it is configured to be 0.3% or less. More preferably, it is configured to be 0.03% or less. The change in evaporation mass is measured, for example, by the method specified by JIS K 2207 "Petroleum Asphalt-Evaporation Test".

The asphalt composition composed of the above-mentioned component compositions is at least blended (mixed) with aggregates and paved as an asphalt mixture, for example, on a predetermined base surface of road pavement. Here, the manufacturing process of the asphalt composition composed of the above-mentioned component compositions will be described with reference to FIG.

(Asphalt base oil production step: S101)
The extract is mixed with straight asphalt supplied to a predetermined mixing place, and agitated by a stirrer (also referred to as a mixing device) for a predetermined time under the condition that the rotation speed is, for example, 140 ° C. or higher and 2000 rpm or higher and 4000 rpm or lower. It is mixed to produce an asphalt base oil as an asphalt base material (S101).

(Step of Adding Silane-Containing Coupling Agent: S102)
Next, a predetermined amount of a silane-containing coupling agent or both an SBS and a silane-containing coupling agent is added to the above-mentioned asphalt base oil, and the stirring device is used, for example, at 180 ° C. or higher and 2000 rpm or higher and 4000 rpm or lower. The asphalt composition is produced by stirring and mixing for a predetermined time under the condition of the number of rotations (S102).

(Asphalt mixture manufacturing process: S103)
After producing the asphalt composition, if necessary, at least an aggregate having a predetermined particle size is added to the asphalt composition, and the asphalt composition is mixed at a predetermined rotation speed, for example, at about 170 ° C. to have desired properties. Manufacture an asphalt mixture (S103). This step is not necessary when selling or shipping the asphalt composition.

In the asphalt mixture in the present embodiment, at least an aggregate is mixed with the asphalt composition having the above-mentioned component composition. Thereby, the peeling resistance can be improved. Therefore, the water resistance can be improved by suppressing the peeling of asphalt.

Hereinafter, examples and comparative examples in the case of using the above-described embodiment will be specifically described.

The viscosities of the asphalt compositions of Examples and Comparative Examples were measured at 180 ° C. as shown in Table 1. In addition, as a test for confirming the peeling resistance of the asphalt compositions of Examples and Comparative Examples, the average peeling rate of the upper and lower surfaces of the specimen in which the asphalt composition and the aggregate were mixed was calculated.

The viscosity at 180 ° C. was measured under the conditions of JPI-5S-54-99 "Viscosity test method using an asphalt-rotational viscometer" at a measurement temperature of 180 ° C., a spindle SC4-21 used, and a spindle rotation speed of 20 rotations / minute. ..

The peeling resistance was examined based on the above boiling water peeling test. Specifically, in this study, a specimen in which the asphalt composition having the composition shown in Table 1 and the hard sandstone aggregate having a thickness of 9.5 mm or more and 13.2 mm or less were mixed according to the procedure shown below was used. For the specimen, 5.5 g ± 0.5 g of each asphalt composition heated at 180 ° C. for 1 hour was added to 100 g ± 0.5 g of hard sandstone aggregate washed with water and dried, and stirred for about 1 minute. And it was made. In this study, 10 specimens are selected from the prepared specimens, and the selected specimens are put into 100 ml of a 1.0 (mol / l) sodium carbonate aqueous solution. Then, in this study, the specimen was heated on a hot plate, heated for 1 minute after reaching 90 ° C., cooled, and then the peeled area ratio of the specimen was measured. Here, in the boiling water peeling test described in ASTM D3625, only the peeling area ratio of the upper surface of the specimen is measured, but in this study, the peeling area ratio of the upper surface of the specimen and the peeling of the lower surface of the specimen are taken. The area ratio was measured. In this study, the average peeling rate of the upper and lower surfaces was calculated from the average of the measured peeling area ratio of the upper surface and the peeling area ratio of the lower surface of the specimen, and the peeling resistance was determined. In this study, when the average peeling rate of the upper and lower surfaces was less than 40%, it was evaluated that the desired peeling resistance was obtained (indicated by "○" in Table 1), and the average peeling rate of the upper and lower surfaces was 40. In the case of% or more, it was evaluated that the desired peeling resistance was not obtained (indicated by "x" in Table 1).

Hereinafter, the materials used in Examples and Comparative Examples will be described.

The asphalt used in Comparative Examples 1 to 10 and Examples 1 to 6 has typical properties such as a needle insertion degree of 67 (1/10 mm), a softening point of 48.0 ° C, and a density of 1,036 kg at 15 ° C. / M ³ .

As the aromatic heavy mineral oil used in Comparative Examples 1 to 10 and Examples 1 to 6, a petroleum-based solvent extract oil or an extract specified in JIS K6200 was used.

The SBS used in Comparative Examples 1 to 10 and Examples 1 to 4 has a molecular weight of about 150,000 (g / mol) and a styrene content of 30% by weight based on the entire SBS.

The rosin used in Comparative Examples 3 and 5 is a disproportionated gum rosin having an acid value of 156 (mgKOH / g: JIS K0070) and a softening point of 77.0 ° C. (JIS K2207).

The dimer acid used in Comparative Examples 4 and 6 is a tall oil fatty acid dimer having 36 carbon atoms and an acid value of 190 to 210 (mgKOH / g: JIS K0070).

The silane-containing coupling agent D used in Comparative Example 7, Comparative Example 9, Example 1, Example 2, and Example 3 has a styrene-butadiene structure. The silane-containing coupling agent D has a viscosity at 25 ° C. of 21,000 (mPa · sec), a number average molecular weight calculated by styrene conversion of 9,000, and a non-volatile content at a heating temperature of 105 ° C. and a heating time of 3 hours. Is over 98%. The hydrolyzing group in the silane-containing coupling agent D is a methoxy group. The flash point of the silane-containing coupling agent D is 250 ° C. or higher. Here, the rate of change in the evaporation mass of the asphalt composition when the silane-containing coupling agent D is added is measured under the conditions detailed in the present embodiment (maintained in air at 163 ° C. for 5 hours). As a result, it increased by 0.0168% as compared with the asphalt composition before heating. It is considered that this is because the non-volatile content of the silane-containing coupling agent D is high, and the mass is increased by the oxide content generated by combining with oxygen by heating.

The silane-containing coupling agent E used in Comparative Example 8, Comparative Example 10, Example 4, Example 5, and Example 6 has a styrene-butadiene structure. The silane-containing coupling agent E has a viscosity at 25 ° C. of 7,500 (mPa · sec), a number average molecular weight calculated by styrene conversion of 9,500, and a non-volatile content at a heating temperature of 105 ° C. and a heating time of 3 hours. Is over 98%. The hydrolyzing group in the silane-containing coupling agent E is an ethoxy group. The flash point of the silane-containing coupling agent E is 250 ° C. or higher. Here, the rate of change in evaporative mass of the asphalt composition when the silane-containing coupling agent E is added is measured under the conditions detailed in the present embodiment (maintained in air at 163 ° C. for 5 hours). As a result, it increased by 0.0162% as compared with the asphalt composition before heating. It is considered that this is because the non-volatile content of the silane-containing coupling agent E is high, and the mass is increased by the oxide content generated by combining with oxygen by heating.

As shown in Table 1, in Comparative Example 1, the peeling resistance was judged without using rosin, dimer acid, a silane-containing coupling agent or the like as peeling preventive agents. As a result, the specimen of Comparative Example 1 had an average peeling rate of 90% on the upper and lower surfaces, and an average peeling rate of 40% or more on the upper and lower surfaces, which is a quality evaluation standard. Therefore, when the peeling inhibitor or the silane-containing coupling agent is not used as in Comparative Example 1, the desired peeling resistance in the asphalt composition cannot be obtained.

In Comparative Example 2, the viscosity of the asphalt composition was increased by increasing the amount of SBS added without using the silane-containing coupling agent as the peeling inhibitor, and the peeling resistance was judged. As a result, although the specimen of Comparative Example 2 had a higher viscosity than that of Comparative Example 1, the average peeling rate of the upper and lower surfaces was 87.5%, and the average peeling rate of the upper and lower surfaces was 40%, which is a quality evaluation standard. That's all. Therefore, it is not possible to obtain the desired peeling resistance of the asphalt composition only by increasing the viscosity of the asphalt composition as in Comparative Example 2.

In Comparative Example 3, rosin was added as a peeling inhibitor, and peeling resistance was judged. As a result, in the specimen of Comparative Example 3, the average peeling rate of the upper and lower surfaces was 55%, which was significantly improved as compared with Comparative Examples 1 and 2, but the average peeling rate of the upper and lower surfaces was 40, which is a quality evaluation standard. It became more than%. Therefore, when a peeling inhibitor using a resin acid is added as in Comparative Example 3, the desired peeling resistance in the asphalt composition cannot be obtained.

In Comparative Example 4, dimer acid was added as a peeling inhibitor, and peeling resistance was judged. As a result, in the specimen of Comparative Example 4, the average peeling rate of the upper and lower surfaces was 47.5%, which was improved as compared with Comparative Examples 1, 2 and 3, but the peeling of the upper and lower surfaces, which is a quality evaluation standard. The average rate was 40% or more. Therefore, when a peeling inhibitor using dimer acid is added as in Comparative Example 4, the desired peeling resistance in the asphalt composition cannot be obtained.

In Comparative Example 5, the amount of rosin added was increased as compared with Comparative Example 3 to determine the peeling resistance. As a result, in the specimen of Comparative Example 5, the average peeling rate of the upper and lower surfaces was 45%, which was improved as compared with each of Comparative Examples 1 to 4, but the average peeling rate of the upper and lower surfaces, which is a quality evaluation standard, was improved. It was over 40%. Therefore, by controlling the amount of rosin added as in Comparative Example 5, it is not possible to obtain the desired peel resistance in the asphalt composition.

In Comparative Example 6, the amount of dimer acid added was increased as compared with Comparative Example 4, and the peeling resistance was judged. As a result, in the specimen of Comparative Example 6, the average peeling rate of the upper and lower surfaces was 47.5%, which was improved as compared with each of Comparative Examples 1 to 4, but the peeling of the upper and lower surfaces, which is a quality evaluation standard, was improved. The average rate was 40% or more. Therefore, by controlling the amount of dimer acid added as in Comparative Example 6, it is not possible to obtain the desired peel resistance in the asphalt composition.

In Comparative Example 7, the peeling resistance was judged by adding 0.5% by weight of the silane-containing coupling agent D as the peeling inhibitor. As a result, the specimen of Comparative Example 7 had an average peeling rate of 40% on the upper and lower surfaces, and an average peeling rate of 40% or more on the upper and lower surfaces, which is a quality evaluation standard. Therefore, even when the silane-containing coupling agent D is added as in Comparative Example 7, if the amount of the silane-containing coupling agent D added is small, the desired peel resistance in the asphalt composition cannot be obtained.

In Comparative Example 8, the peeling resistance was judged by adding 0.5% by weight of the silane-containing coupling agent E as the peeling inhibitor. As a result, the specimen of Comparative Example 8 had an average peeling rate of 50% on the upper and lower surfaces, and an average peeling rate of 40% or more on the upper and lower surfaces, which is a quality evaluation standard. Therefore, even when the silane-containing coupling agent E is added as in Comparative Example 8, if the amount of the silane-containing coupling agent E added is small, the desired peel resistance in the asphalt composition cannot be obtained.

In Comparative Example 9, the peeling resistance was judged by adding 4.0% by weight of the silane-containing coupling agent D as the peeling inhibitor. As a result, in the specimen of Comparative Example 9, the asphalt base oil, the aromatic heavy mineral oil, and the SBS and the silane-containing coupling agent were not mixed, and the asphalt composition could not be produced. Therefore, even when the silane-containing coupling agent D is added as in Comparative Example 9, if the amount of the silane-containing coupling agent D added is large, the asphalt composition itself cannot be produced. The purpose cannot be achieved.

In Comparative Example 10, the peeling resistance was judged by adding 4.0% by weight of the silane-containing coupling agent E as the peeling inhibitor. As a result, in the specimen of Comparative Example 10, the asphalt base oil, the aromatic heavy mineral oil, and the SBS and the silane-containing coupling agent were not mixed, and the asphalt composition could not be produced. Therefore, even when the silane-containing coupling agent E is added as in Comparative Example 10, if the amount of the silane-containing coupling agent E added is large, the asphalt composition itself cannot be produced. The purpose cannot be achieved.

On the other hand, in Examples 1 to 6, the blending of the asphalt base oil, SBS, and the silane-containing coupling agent is within the range of the component composition specified in the present embodiment described above. Therefore, in Examples 1 to 6, it was confirmed that the average peeling rate of the upper and lower surfaces was less than 40%, and it was possible to obtain the desired peeling resistance. In Examples 1 to 6, the viscosity at 180 ° C. is 216 mPa · sec or more and 284 mPa · sec or less. Therefore, it is possible to ensure safety during heating such as during manufacturing and storage.

Specifically, in Example 1, 1.5% by weight of the silane-containing coupling agent D was added as a peeling inhibitor, and the peeling resistance was judged. As a result, it can be confirmed that the specimen of Example 1 has an average peeling rate of 17.5% on the upper and lower surfaces, which is improved in peeling resistance as compared with Comparative Examples 1 to 10.

In particular, in Example 2, the amount of the silane-containing coupling agent D added is 3.0% by weight, which is larger than the amount of the silane-containing coupling agent D added in Example 1. As a result, it was confirmed that in Example 2, the average peeling rate of the upper and lower surfaces was 5%, and the peeling resistance could be significantly improved as compared with Comparative Examples 1 to 10.

Further, in Example 3, a silane-containing coupling agent E was added in an amount of 1.5% by weight as a peeling inhibitor, and the peeling resistance was judged. As a result, it can be confirmed that the specimen of Example 3 has an average peeling rate of 25% on the upper and lower surfaces, which is improved in peeling resistance as compared with Comparative Examples 1 to 10.

In particular, in Example 4, the amount of the silane-containing coupling agent E added is 3.0% by weight, which is larger than the amount of the silane-containing coupling agent E added in Example 3. As a result, it was confirmed that in Example 5, the average peeling rate of the upper and lower surfaces was 2.5%, and the peeling resistance could be significantly improved as compared with Comparative Examples 1 to 10.

In Example 5, the peeling resistance was judged by adding 2.0% by weight of the silane-containing coupling agent D as a peeling inhibitor without adding SBS. As a result, it can be confirmed that the specimen of Example 5 has an average peeling rate of 7.5% on the upper and lower surfaces, which is improved in peeling resistance as compared with Comparative Examples 1 to 10. As described above, in the present invention, it can be confirmed that the peel resistance is improved as compared with Comparative Examples 1 to 10 even if SBS is not contained.

In Example 6, the peeling resistance was judged by adding 2.0% by weight of the silane-containing coupling agent E as a peeling inhibitor without adding SBS. As a result, it can be confirmed that the specimen of Example 6 has an average peeling rate of 5% on the upper and lower surfaces, which is improved in peeling resistance as compared with Comparative Examples 1 to 10. As described above, in the present invention, it can be confirmed that the peel resistance is improved as compared with Comparative Examples 1 to 10 even if SBS is not contained.

Claims (3)

Asphalt base oil and
Containing at least a silane-containing coupling agent,
The silane-containing coupling agent has a styrene-butadiene structure and has a styrene-butadiene structure.
The content of the silane-containing coupling agent shall be 1.5% by weight or more and 3.0% by weight or less.
Asphalt composition characterized by. The asphalt composition according to claim 1, wherein the asphalt composition has an evaporation mass change rate of 1% or less. At least an aggregate is mixed with the asphalt composition according to claim 1 or 2.
Asphalt mixture characterized by.

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