JP6475390B1 - Asphalt composition and asphalt mixture - Google Patents

Abstract

A technique for improving water resistance performance by suppressing asphalt peeling is provided. An asphalt composition of the present disclosure includes at least an asphalt base oil and a silane-containing coupling agent, and the silane-containing coupling agent has a butadiene structure and contains the silane-containing coupling agent. The amount is 0.8% by weight or more. Moreover, the asphalt mixture of the present disclosure is characterized in that at least an aggregate is mixed with the asphalt composition. [Selection figure] None

Description

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

  In recent years, the main cause of damage to asphalt pavement is the asphalt peeling phenomenon in which rainwater or groundwater penetrates between asphalt and aggregate and the asphalt covered on the surface of the aggregate peels off. It was. When such an asphalt peeling phenomenon occurs, the function of adhering the aggregates decreases, and there is a possibility that damage such as cracks and potholes is likely to occur.

  Resin acid such as dimer acid and rosin, saturated fatty acid such as stearic acid, palmitic acid and myristic acid, and unsaturated such as oleic acid, linoleic acid, and ricillenic acid A method for suppressing asphalt peeling by mixing a fatty acid such as a fatty acid with asphalt as a peeling inhibitor has 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, sufficient anti-peeling effects cannot be obtained especially for acidic rocks such as granite. Therefore, a technique for suppressing asphalt peeling is also required for these rocks.

JP, 2006-121320, A JP-A-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 asphalt peeling.

  According to one aspect of the present disclosure, at least an asphalt base oil and a silane-containing coupling agent, the silane-containing coupling agent has a butadiene structure, and the content of the silane-containing coupling agent is The technique characterized by being 0.8 weight% or more can be provided.

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

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

  As described above, the present inventors have intensively studied the component composition and the content ratio of the asphalt composition and the asphalt composite material. As a result, the inventors newly found out that a specific silane-containing coupling agent is added in order to improve water resistance performance by suppressing asphalt peeling, and completed the present invention. Hereinafter, embodiments of the asphalt composition and the asphalt mixture according to 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 becomes difficult to peel from the aggregate due to an increase in the peeling resistance. .

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

Asphalt base oil: 89.0% by weight or more, 99.2% by weight or less SBS: 7.0% by weight or less Silane-containing coupling agent: 0.8% by weight or more and 4.0% 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, asphalt such as straight asphalt, propane-deasphalted asphalt, etc., solvent-deasphalted asphalt, blown asphalt, semi-blown asphalt, etc. may be used as appropriate. The asphalt base oil further preferably 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 89.0 wt% or more and 99.2 wt% or less. It is preferable.

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

(Solvent removal asphalt)
Solvent deasphalted asphalt corresponds to the residue obtained by extracting solvent degreased oil (high-viscosity lubricating oil fraction) from the vacuum distillation residue (see “New Petroleum Dictionary”, Petroleum Institute, 1982, p. 308). . In particular, when propane or propane and butane is used as a solvent, it is called as propane deasphalting asphalt.

(Blown asphalt)
The blown 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 specified 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 extraction using a polar solvent such as furfural obtained by removing a solvent-removed oil obtained by removing the vacuum distillation residue of crude oil with propane or the like. By doing so, the solvent extraction oil at the time of obtaining bright stock (heavy lubricating oil), ie, an extract, can be used. In particular, in this 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 storage stability. If the amount of the thermoplastic elastomer added is large, the extract The required amount of addition also increases. Moreover, when the extract more than necessary with respect to the addition amount of a thermoplastic elastomer is added, the elasticity modulus of an asphalt composition will fall.

  The extract content of the entire asphalt composition in the present embodiment includes penetration, softening point, storage stability, complex elastic modulus indicating strength, dynamic stability (DS) in a wheel tracking test, and low-temperature properties. It is determined in consideration of bending work amount and bending stiffness. In the range examined in the present embodiment, the extract content relative to the entire asphalt composition is preferably 2.0 wt% or more and 8.0 wt% 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 here is the weight percent of styrene contained in the SBS.

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

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

  In the asphalt composition of the present embodiment, it is not essential that SBS is contained, and it may not be contained, but in order to solve the above-described problem, the asphalt composition of the present embodiment The SBS content relative to the whole is preferably 7.0% by weight or less. By setting the SBS content to 7.0% by weight or less, it is possible to maintain the asphalt continuous phase, and it is possible to improve the water resistance of the dense particle mixture having excellent water barrier properties. On the other hand, when it is desired to produce a drainage or highly permeable asphalt mixture in which voids are actively provided inside the pavement, the SBS content of 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-described 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, the complexity of selecting and mixing two or more types of SBS can be eliminated, and the manufacturing labor can be reduced, which is preferable.

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

・・・（１）

... (1)

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

  Since the silane-containing coupling agent having the above-described structure has a butadiene structure, it has a high affinity with asphalt, and since it has a hydrolyzable group, it has a high binding force to the aggregate part. . For this reason, it becomes possible to improve the adhesiveness of an aggregate and asphalt by adding a silane containing coupling agent to the asphalt composition in this embodiment.

  In addition, it is preferable that the silane containing coupling agent utilized suitably by this embodiment has the following properties. For example, the viscosity at 25 ° C. is preferably 500 (mPa · s) or more, and more preferably about 1,100 (mPa · s) or more and 1,600 (mPa · s) or less. For example, it is preferable that the non-volatile content in the heating temperature of 105 ° C. and the heating time of 3 hours is more than 98%. Furthermore, for example, the number average molecular weight calculated by styrene conversion is preferably 1,000 or more and 20,000 or less, and more preferably about 6,000 or more and 6,200 or less.

  Content of the silane containing coupling agent with respect to the whole asphalt composition of this embodiment is 0.8 weight% or more. Thereby, peeling resistance can be improved. For this reason, water resistance performance can be improved by suppressing exfoliation of asphalt. On the other hand, when the content of the silane-containing coupling agent is less than 0.8% by weight, the peel resistance cannot be increased. For this reason, content of a silane containing coupling agent shall be 0.8 weight% or more. The peel resistance can be improved even when the content of the silane-containing coupling agent is 4.0% by weight. However, when the content of the silane-containing coupling agent is large, the peel resistance is improved. The quality of the material becomes excessive and the raw material cost increases. For this reason, 4.0 weight% or less is preferable and, as for content of a silane containing coupling agent, it is more preferable that it is 2.5 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 suitably used in the present embodiment is added to asphalt base oil having a high temperature of, for example, 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 or storage can be further improved. Here, the flash point of the silane-containing coupling agent is measured by, for example, a method defined by JIS K 2207 “Petroleum Asphalt—Flash Point Test”.

(Peeling rate)
The asphalt composition of this embodiment has an average peel rate of the upper and lower surfaces of less than 40%. Thereby, desired peeling resistance can be obtained. On the other hand, when the average peel rate on the upper and lower surfaces is 40% or more, desired peel resistance cannot be obtained. As will be described later, the average peel rate of the upper and lower surfaces is a test method (also referred to as boiling water peel test, boil) specified by ASTM D3625 “Standard Practice for Effect of Water on Biological-Coated Aggregating Using Boiling Water”. Hereinafter, it is calculated by the average of the peeled area ratio on the upper surface and the peeled area ratio on the lower surface of the specimen tested based on the boiling water peel test).

(Evaporation mass change rate)
The asphalt composition of this embodiment measured the rate of mass change when the specimen was heated to 163 ° C. in air for 5 hours, and the rate of change between the mass before heating and the mass after heating was as follows. 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 by, for example, a method defined by JIS K 2207 “Petroleum Asphalt—Evaporation Test”.

  The asphalt composition comprised by the component composition mentioned above mix | blends (mixes) at least an aggregate, and is paved on the predetermined base surface of a road pavement as an asphalt compound material, for example. Here, the manufacturing process of the asphalt composition comprised by the component composition mentioned above is demonstrated using FIG.

(Asphalt base oil production process: S101)
Extracts are mixed with straight asphalt supplied to a predetermined mixing place, and the mixture is stirred by a stirrer (also referred to as a mixing device), for example, under a condition that the rotational speed is 140 ° C. or higher and 2,000 rpm to 4,000 rpm. And asphalt base oil as an asphalt base material is generated (S101).

(Silane-containing coupling agent addition step: S102)
Next, a predetermined amount of a silane-containing coupling agent or both SBS and a silane-containing coupling agent is added to the above-described asphalt base oil, and, for example, 180 ° C. or higher, 2,000 rpm or higher 4 The asphalt composition is generated by stirring and mixing for a predetermined time under the condition that the rotation speed is 1,000 rpm or less (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 mixed at a predetermined rotation speed, for example, at about 170 ° C. to have a desired property. Asphalt composite material is manufactured (S103). This step is not necessary when selling and shipping asphalt compositions.

  In the asphalt mixture according to the present embodiment, at least aggregate is mixed with the asphalt composition having the above-described component composition. Thereby, peeling resistance can be improved. For this reason, water resistance performance can be improved by suppressing exfoliation of asphalt.

  Hereinafter, specific examples will be described with reference to examples and comparative examples when the above-described embodiment is used.

  About the asphalt composition of an Example and a comparative example, as shown in Table 1, the viscosity in 180 degreeC was measured. Moreover, about the asphalt composition of an Example and a comparative example, the peeling rate average of the upper and lower surfaces of the test body which mixed the asphalt composition and the aggregate was computed as a test for confirming peeling resistance.

  The viscosity at 180 ° C. was measured under the conditions of JPI-5S-54-99 “Viscosity Test Method Using Asphalt-Rotational Viscometer” at a measuring temperature of 180 ° C., a spindle SC4-21, a spindle rotation speed of 20 revolutions / minute. .

  The peel resistance was examined based on the boiling water peel test. In detail, in this examination, the specimen which mixed the asphalt composition of the composition shown in Table 1 and the hard sandstone aggregate of 9.5 mm or more and 13.2 mm or less by the procedure shown below was used. The test specimen was added with 5.5 g ± 0.5 g of each asphalt composition heated at 180 ° C. for 1 hour to 100 g ± 0.5 g of hard sandstone aggregate washed and dried, and stirred for about 1 minute. Thus, it was produced. In this examination, ten pieces are selected from the prepared specimens, and the selected specimens are put into 100 ml of 1.0 (mol / l) sodium carbonate aqueous solution. Thereafter, in this study, the specimen was heated with a hot plate, heated to 90 ° C. for 1 minute, 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 peel area ratio on the upper surface of the specimen is measured, but in this study, the peel area ratio on the upper face of the specimen and the peel on the lower face of the specimen are measured. The area ratio was measured. In this examination, the average of the peel area ratio of the measured upper surface and the peel area ratio of the lower surface of the specimen was calculated to calculate the average peel rate of the upper and lower surfaces and determine the peel resistance. In this study, when the average peel rate on the upper and lower surfaces was less than 40%, it was evaluated that the desired peel resistance was obtained (indicated by “◯” in Table 1), and the average peel rate on the upper and lower surfaces was 40. In the case of% or more, it was evaluated that the desired peel resistance was not obtained (indicated by “x” in Table 1).

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

The asphalt used in Comparative Examples 1 to 8 and Examples 1 to 8 has typical properties of a penetration of 67 (1/10 mm), a softening point of 48.0 ° C., and a density at 15 ° C. of 1036 kg. / M ³ .

  As the aromatic heavy mineral oil used in Comparative Examples 1 to 8 and Examples 1 to 8, petroleum solvent extracted oil and extracts defined in JISK6200 were used.

  The SBS used in Comparative Examples 1 to 8 and Examples 1 to 6 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 (mg KOH / 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 dimerization product having 36 carbon atoms and an acid value of 190 to 210 (mg KOH / g: JIS K0070).

  The silane-containing coupling agent A used in Comparative Example 7, Example 1, Example 2, Example 3, and Example 7 has a butadiene structure. The silane-containing coupling agent A has a viscosity of 1,600 (mPa · s) at 25 ° C., a number average molecular weight calculated by styrene conversion of 6,000, a non-volatile content at a heating temperature of 105 ° C. and a heating time of 3 hours. Is over 98%. The hydrolyzable group in the silane-containing coupling agent A is a methoxy group. The flash point of the silane-containing coupling agent A is 288 ° C. or higher. Here, the evaporation mass change rate of the asphalt composition when the silane-containing coupling agent A is added is measured under the conditions detailed in this embodiment (the state heated to 163 ° C. in air for 5 hours). As a result, it increased by 0.0134% compared with the asphalt composition before heating. This is presumably because the non-volatile content of the silane-containing coupling agent A is high, and the mass is increased by the oxide content generated by bonding with oxygen by heating.

  The silane-containing coupling agent B used in Comparative Example 8, Example 4, Example 5, Example 6, and Example 8 has a butadiene structure. The silane-containing coupling agent B has a viscosity of 1,100 (mPa · sec) at 25 ° C., a number average molecular weight calculated by styrene conversion of 6,200, a non-volatile content at a heating temperature of 105 ° C. and a heating time of 3 hours. Is over 98%. The hydrolyzable group in the silane-containing coupling agent B is an ethoxy group. The flash point of the silane-containing coupling agent B is 294 ° C. or higher. Here, the evaporation mass change rate of the asphalt composition when the silane-containing coupling agent B is added is measured under the conditions detailed in this embodiment (the state heated to 163 ° C. in air for 5 hours). As a result, it increased by 0.0210% compared to the asphalt composition before heating. This is presumably because the non-volatile content of the silane-containing coupling agent B is high, and the mass is increased by the oxide content generated by bonding with oxygen by heating.

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

  The comparative example 2 increased the viscosity of the asphalt composition by increasing the addition amount of SBS without using the silane-containing coupling agent which is a peeling inhibitor, and judged the peeling resistance. As a result, although the specimen of Comparative Example 2 has increased viscosity as compared with Comparative Example 1, the upper and lower surface peel rate average is 87.5%, and the upper and lower surface peel rate average is 40%. That's it. For this reason, the desired peeling resistance in the asphalt composition cannot be obtained only by increasing the viscosity of the asphalt composition as in Comparative Example 2.

  In Comparative Example 3, rosin was added as an anti-peeling agent, and peel resistance was judged. As a result, the specimen of Comparative Example 3 had an average peel rate of 55% on the upper and lower surfaces, which was greatly improved as compared with Comparative Examples 1 and 2, but the peel rate average of 40 on the upper and lower surfaces, which is a pass / fail evaluation criterion. It became more than%. For this reason, when the peeling inhibitor by a resin acid is added like the comparative example 3, the desired peeling resistance in an asphalt composition cannot be obtained.

  In Comparative Example 4, dimer acid was added as an anti-peeling agent, and the peel resistance was judged. As a result, the specimen of Comparative Example 4 had an average peeling rate of 47.5% on the upper and lower surfaces, which was improved as compared with Comparative Examples 1, 2, and 3. The average rate was 40% or more. For this reason, when the peeling inhibitor by a dimer acid is added like the comparative example 4, the desired peeling resistance in an asphalt composition cannot be obtained.

  In Comparative Example 5, peeling resistance was judged by increasing the amount of rosin added compared to Comparative Example 3. As a result, although the specimen of Comparative Example 5 had an average peel rate of 45% on the upper and lower surfaces compared to each of Comparative Examples 1 to 4, the peel rate average on the upper and lower faces, which is a pass / fail evaluation criterion. More than 40%. For this reason, by controlling the amount of rosin added as in Comparative Example 5, the desired peel resistance in the asphalt composition cannot be obtained.

  In Comparative Example 6, peeling resistance was judged by increasing the amount of dimer acid added as compared with Comparative Example 4. As a result, the specimen of Comparative Example 6 has an average peel rate of 47.5% on the upper and lower surfaces, which is improved as compared with each of Comparative Examples 1 to 4, but the peel on the upper and lower surfaces, which is a pass / fail evaluation criterion. The average rate was 40% or more. For this reason, by controlling the amount of dimer acid added as in Comparative Example 6, the desired peel resistance in the asphalt composition cannot be obtained.

  In Comparative Example 7, 0.5% by weight of the silane-containing coupling agent A was added as a peeling inhibitor, and the peeling resistance was judged. As a result, the specimen of Comparative Example 7 had an average peel rate on the upper and lower surfaces of 40% and an average peel rate on the upper and lower surfaces of 40% or higher, which is a quality evaluation standard. For this reason, even if it is a case where the silane containing coupling agent A is added like the comparative example 7, when the addition amount is a small amount, the desired peeling resistance in an 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 B as a peeling inhibitor. As a result, the specimen of Comparative Example 8 had an upper and lower surface peel rate average of 50%, and an upper and lower surface peel rate average of 40% or more, which is a quality evaluation standard. For this reason, even if it is a case where the silane containing coupling agent B is added like the comparative example 8, when the addition amount is a small amount, the desired peeling resistance in an asphalt composition cannot be obtained.

  On the other hand, as for Examples 1-8, all mix | blend of asphalt base oil, SBS, and a silane containing coupling agent exists in the range of the component composition prescribed | regulated in this embodiment mentioned above. For this reason, in Examples 1-8, the average peel rate on the upper and lower surfaces was less than 40%, and it was confirmed that the desired peel resistance could be obtained. In Examples 1 to 8, the viscosity at 180 ° C. is 211 mPa · second or more and 325 mPa · second or less. For this reason, it becomes possible to ensure the safety at the time of heating at the time of manufacture or storage.

  Specifically, in Example 1, 0.8% by weight of the silane-containing coupling agent A 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 peel rate of 22.5% on the upper and lower surfaces and improved peel resistance as compared with Comparative Examples 1-8.

  Particularly, in Example 2, the addition amount of the silane-containing coupling agent A is 2.5 wt%, which is higher than the addition amount of the silane-containing coupling agent A in Example 1. Thereby, it was confirmed that Example 2 can significantly improve the peeling resistance as compared with Comparative Examples 1 to 8, with the average peeling rate of the upper and lower surfaces being 0%.

  In particular, in Example 3, the addition amount of the silane-containing coupling agent A is 4.0% by weight, which is higher than the addition amount of the silane-containing coupling agent A in Example 1. Thereby, it was confirmed that Example 3 can remarkably improve the peeling resistance as compared with Comparative Examples 1 to 8, with the average peeling rate of the upper and lower surfaces being 0%.

  As described above, in Example 2, the average peel rate on the upper and lower surfaces is 0%, and in Example 3, the average peel rate on the upper and lower surfaces is 0%. That is, even if the content of the silane-containing coupling agent A is increased from 2.5% by weight to 4.0% by weight, the peel resistance obtained in each case is almost equal. For this reason, when 4.0 weight% of silane containing coupling agent A is contained, peeling resistance will become an excess quality and the increase in raw material cost is suggested. For this reason, the content of the silane-containing coupling agent A is more preferably 2.5% by weight or less.

  In Example 4, 0.8% by weight of silane-containing coupling agent B was added as an anti-peeling agent, and the peel resistance was judged. As a result, it can be confirmed that the specimen of Example 4 has an average peel rate of 25% on the upper and lower surfaces and improved peel resistance compared to Comparative Examples 1-8.

  In particular, in Example 5, the addition amount of the silane-containing coupling agent B is 2.5 wt%, which is higher than the addition amount of the silane-containing coupling agent B in Example 4. Thereby, it was confirmed that Example 5 was able to remarkably improve the peeling resistance as compared with Comparative Examples 1 to 8, with an average peeling rate of 5% on the upper and lower surfaces.

  In particular, in Example 6, the addition amount of the silane-containing coupling agent B is 4.0 wt%, which is higher than the addition amount of the silane-containing coupling agent B in Example 4. Thereby, in Example 6, it was confirmed that the average peel rate of the upper and lower surfaces was 0%, and the peel resistance could be remarkably improved as compared with Comparative Examples 1-8.

  As described above, Example 5 has an upper and lower surface peel rate average of 5%, and Example 6 has an upper and lower surface peel rate average of 0%. That is, even if the content of the silane-containing coupling agent B is increased from 2.5% by weight to 4.0% by weight, the peel resistance obtained in each case is almost equal. For this reason, when 4.0 weight% of silane containing coupling agent B is contained, peeling resistance becomes excess quality, and the increase in raw material cost is suggested. For this reason, the content of the silane-containing coupling agent B is more preferably 2.5% by weight or less.

  In Example 7, 2.0% by weight of the silane-containing coupling agent A was added as an anti-peeling agent without adding SBS, and the peel resistance was judged. As a result, it can be confirmed that the specimen of Example 7 has an average peel rate of 2.5% on the upper and lower surfaces, and the peel resistance is improved as compared with Comparative Examples 1-8. Thus, in this invention, even if SBS is not contained, it can confirm that peeling resistance is improving compared with Comparative Examples 1-8.

  In Example 8, 2.0 wt% of the silane-containing coupling agent B was added as an anti-peeling agent without adding SBS, and the peel resistance was judged. As a result, it can be confirmed that the specimen of Example 8 has an average peel rate of 5% on the upper and lower surfaces and improved peel resistance compared to Comparative Examples 1-8. Thus, in this invention, even if SBS is not contained, it can confirm that peeling resistance is improving compared with Comparative Examples 1-8.

Claims (4)

Asphalt base oil,
A silane-containing coupling agent,
The silane-containing coupling agent is
A butadiene structural unit, an ethylene structural unit, and a hydrolyzable group bonded to silicon bonded to the ethylene structural unit ,
The number average molecular weight calculated by styrene conversion is 1,000 or more and 20,000 or less,
The content of the silane-containing coupling agent is 0.8% by weight or more,
Asphalt composition characterized by the above.   The asphalt composition according to claim 1, wherein the asphalt composition has an evaporation mass change rate of 1% or less. Mixing at least aggregate with the asphalt composition according to claim 1 or 2,
Asphalt composite characterized by Producing an asphalt base oil;
Adding the silane-containing coupling agent to the asphalt base oil in an amount of 0.8% by weight or more of the total amount,
The silane-containing coupling agent is
A butadiene structural unit, an ethylene structural unit, and a hydrolyzable group bonded to silicon bonded to the ethylene structural unit,
The number average molecular weight calculated by styrene conversion is 1,000 or more and 20,000 or less.
A method for producing an asphalt composition.

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