JP6607672B2 - Polymer and asphalt composition - Google Patents

Description

  The present invention relates to polymers and asphalt compositions.

Conventionally, asphalt compositions have been widely used in applications such as road pavement, waterproof sheets, sound insulation sheets, and roofing. At that time, many attempts have been made to improve the properties by adding various polymers to asphalt. As the polymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, rubber latex, block copolymer composed of conjugated diene and vinyl aromatic hydrocarbon, and the like are used.
In recent years, as cost reduction, there are increasing demands such as reduction of additive amount, shortening of manufacturing time, reduction of loss rate due to thermal deterioration, or reduction of maintenance frequency. For this reason, for example, increasing the molecular weight of the block copolymer composed of the conjugated diene and the vinyl aromatic hydrocarbon has been proposed because of higher mechanical strength such as softening point, elongation and elastic modulus. . However, there are problems that the amount of addition cannot always be sufficiently reduced, thermal degradation during storage, and degradation by sunlight (ultraviolet rays) after road paving.
In order to improve these, hydrogenated polymer blocks obtained by copolymerizing a conjugated diene monomer and a vinyl aromatic monomer have been studied as in Patent Documents 1 to 3.

Japanese Laid-Open Patent Publication No. 2005-126485 US Patent Application Publication No. 2003/0149140 JP 2012-246378

However, even the methods disclosed in Patent Documents 1 to 3 have not yet obtained satisfactory results, and further improvements are desired.
The problem to be solved by the present invention is to provide a polymer that has a high heat aging resistance at the time of storage and can improve the workability of the asphalt composition.

  In order to solve the above-mentioned problems, the inventors of the present invention have made it possible to increase the heat aging resistance during storage and to improve the workability of the asphalt composition by using a polymer having a specific molecular structure and a specific shape. The headline and the present invention were completed.

That is, the present invention is as follows.
[1] A polymer comprising a conjugated diene monomer unit and a vinyl aromatic monomer unit,
The polymer has a polymer block (A) mainly composed of a vinyl aromatic monomer unit, and a copolymer block (B) containing a conjugated diene monomer unit and a vinyl aromatic monomer unit. ,
The content of the vinyl aromatic monomer unit in the polymer block (A) is 90% by mass or more,
The content of vinyl aromatic monomer units in the copolymer block (B) is 10% by mass or more and 60% by mass or less,
The content of the polymer block (A) is 20% by mass or more and 40% by mass or less,
The distance between the Bragg surfaces of the polymer is 27 nm or more and 48 nm or less,
The hydrogenation rate of double bonds in the conjugated diene monomer unit exceeds 90 mol%,
A polymer having a tan δ peak height of 0 ° C. or lower obtained from viscoelasticity measurement of 0.8 or more and 1.4 or less.
[2] The polymer according to [1], wherein the content of the vinyl aromatic monomer unit is 20% by mass or more.
[3] The copolymer block in (B), relative to the content 100 wt% of a vinyl aromatic monomer unit, the short chain vinyl aromatic consisting 2-6 vinyl aromatic monomer unit The polymer according to [1] or [2] , wherein the content of the monomer polymerization portion is 50% by mass or more.
[4] the content of the short chain vinyl aromatic monomer polymerization moiety is 70 mass% or more, the polymer according to [3].
[5] The polymer according to any one of [1] to [4] , which has a functional group.
[6] An asphalt composition comprising 0.5 to 50 parts by mass of the polymer according to any one of [1] to [5] and 100 parts by mass of asphalt.
[7] The total amount of the polymer according to any one of [1] to [5] and the block copolymer (a) is 0.5 parts by mass or more and 50 parts by mass or less,
An asphalt composition containing 100 parts by weight of asphalt,
The block copolymer (a) is a polymer block (A) mainly composed of at least one vinyl aromatic monomer unit, and a polymer block (C) mainly composed of at least one conjugated diene monomer unit. Consists of
The asphalt composition whose content of the said block copolymer (a) in the said total amount is 15-85 mass%.

  The polymer of the present invention has high heat aging resistance during storage of the asphalt composition, and can improve workability.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiment, and can be implemented with various modifications within the scope of the gist.
The polymer of this embodiment is a polymer containing a conjugated diene monomer unit and a vinyl aromatic monomer unit,
The polymer has a polymer block (A) mainly composed of a vinyl aromatic monomer unit, and a copolymer block (B) containing a conjugated diene monomer unit and a vinyl aromatic monomer unit. ,
The distance between the Bragg surfaces of the polymer is 27 nm or more and 50 nm or less,
The hydrogenation rate of the double bond in the conjugated diene monomer unit exceeds 90 mol%. Here, the constitutional unit constituting the polymer is referred to as “˜monomer unit”, and when described as a polymer material, “unit” is omitted and simply “˜monomer”.

  In the present specification, “mainly composed of a vinyl aromatic monomer unit” means that the content of a predetermined monomer unit in the block is preferably 60% by mass or more, more preferably 80% by mass. It means mass% or more, more preferably 90 mass% or more, and still more preferably 95 mol% or more.

[Polymer structure]
In the present embodiment, the structure of the polymer is not particularly limited, and examples thereof include structures represented by the following formulas (i) to (vi).
(AB) n (i)
B- (A-B) n (ii)
A- (B-A) n (iii)
A- (B-A) n-X (iv)
[(A−B) k] m−X (v)
[(A−B) k−A] m−X (vi)
(In the above formulas (i) to (vi), A represents a block mainly composed of a vinyl aromatic monomer unit, and B represents a copolymer containing a conjugated diene monomer unit and a vinyl aromatic monomer unit. Represents a polymer block, X represents a residue of a coupling agent or a residue of a polymerization initiator such as polyfunctional organolithium, m, n and k represent an integer of 1 or more, and an integer of 1 to 5 It is preferable that

When a plurality of blocks A and B are present in the block copolymer before hydrogenation, the structures such as molecular weight and composition may be the same or different.
The polymerization initiator such as a coupling agent or polyfunctional organolithium is not particularly limited. For example, silicon tetrachloride, tin tetrachloride, epoxidized soybean oil, polyhalogenated hydrocarbon compound, carboxylic acid ester compound, polyvinyl compound Bisphenol type epoxy compounds, alkoxysilane compounds, halogenated silane compounds, ester compounds, 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane, and the like. It may be a mixture of a coupling body in which X is a residue of a coupling agent and a non-coupling body in which X is not present or X is a residue of a polymerization initiator.
Note that the boundaries and the end portions of the blocks do not necessarily have to be clearly distinguished. For example, a copolymer block of a vinyl aromatic monomer unit and a conjugated diene monomer unit may be present.

In the present embodiment, the vinyl aromatic monomer units in the copolymer block (B) may be uniformly distributed, or may be distributed in a tapered shape, a staircase shape, a convex shape, or a concave shape. A plurality of these may coexist. In the polymer block mainly composed of vinyl aromatic monomer units, a plurality of segments having different contents of vinyl aromatic monomer units may coexist.
The content of the vinyl aromatic monomer unit in the copolymer block (B) immediately after the start of the polymerization of the copolymer block (B) is S1, and the copolymer at the time when half of the introduced monomers are polymerized The content of the vinyl aromatic monomer unit in the copolymer block (B) when the total amount of the introduced monomer was polymerized was S2, and the content of the vinyl aromatic monomer unit in the copolymer block (B) was S3. In this case, a structure that satisfies the relationship of S2 / S1> 1 and S3 / S2> 1 is more preferable in terms of compatibility with asphalt.

In view of the low polymer addition amount to be added to the asphalt, the recoverability after tension of the asphalt composition, and the anti-aggregation property of the aggregate, a linear structure is preferable by sequential polymerization, not a coupling structure. Among them, the ABA structure is preferable.
The coupling structure is preferably a linear structure from the viewpoint of low viscosity of the asphalt composition, and a radial structure is preferable from the viewpoint of a high softening point of the asphalt composition. Further, the radial structure is preferably a 3-branch or 4-branch structure, and more preferably has both a 3-branch and a 4-branch structure. Further, the ratio of the 3 branch structure to the 4 branch structure is 5/95 to 95/5 for 3 branch / 4 branch, and 90/4 or less for 3 branch / 4 branch is preferable from the viewpoint of high softening point. 25 or less is more preferable, 60/40 or less is more preferable, and 40/60 or less is most preferable. Further, from the viewpoint of low viscosity, 3/4 branch is preferably 10/90 or more, more preferably 25/75 or more, still more preferably 50/50 or more, and most preferably 70/30 or more.

The distance between the Bragg surfaces calculated from the primary peak obtained from the X-ray small angle scattering (SAXS) analysis of the polymer used in the present embodiment is high in terms of recoverability after tensile of the asphalt composition and resistance to aggregate peeling. 27 nm or more, preferably 28 nm or more, more preferably 29 nm or more, and most preferably 30 nm or more.
Further, in terms of workability, it is 50 nm or less, preferably 48 nm or less, more preferably 46 nm or less, and most preferably 45 nm or less.
Moreover, 38.5 nm or less is preferable at the point of high compatibility with asphalt, 38.0 nm or less is more preferable, 37.5 nm or less is more preferable, and 37 nm or less is the most preferable.
In addition, the Bragg surface space | interval of a polymer can be measured by the method of the Example description mentioned later.
The value of the Bragg plane spacing is the specific energy obtained by dividing the stirring power by the amount of the reaction solution in the polymerization tank and the number of additions of the conjugated diene monomer and the vinyl aromatic monomer in the polymerization of the copolymer block (B). Alternatively, it can be adjusted to 27 nm or more and 50 nm or less by controlling the addition time.

Specifically, the specific energy value is within the range of 0.1 kw / m ^{3 to} 0.4 kw / m ³ and the number of additions is set to 3 times or more, or the addition time is set to 10 to 70 minutes. 27 nm or more and 38.5 nm or less, the specific energy value is in the range of 0.1 kw / m ^{3 to} 0.5 kw / m ³ and the number of additions is 3 times or more, or addition By setting the time to 10 to 70 minutes, it can be adjusted to 27 nm or more and 50 nm or less.
The Bragg surface spacing tends to increase by increasing the specific energy.

The distance between the Bragg surfaces can be measured by the method described in Examples below.
In the present embodiment, the content of the vinyl aromatic monomer unit in the polymer is 20 mass in terms of separation stability of the asphalt composition, heat aging resistance, recoverability after tension, and aggregate peel resistance. % Or more is preferable. 33 mass% or more is more preferable, 37 mass% or more is further more preferable, and 40 mass% or more is the most preferable. Moreover, 60 mass% or less is preferable at the point of the isolation | separation stability of an asphalt composition, a softness | flexibility, the recovery | restoration property after tension | pulling, and aggregate peel resistance. 55 mass% is more preferable, 48 mass% or less is further more preferable, and 45 mass% or less is the most preferable.
In addition, content of the block which has a vinyl aromatic monomer unit as a main body can be measured by the method of the Example description later mentioned.

In the present embodiment, the content of the block (A) mainly composed of vinyl aromatic monomer units in the polymer is preferably 10% by mass or more from the viewpoint of recovery after tension and resistance to peeling of aggregates. . 13 mass% or more is more preferable, 16 mass% or more is further more preferable, and 17 mass% or more is the most preferable. Moreover, 40 mass% or less is preferable at the point of the high softness | flexibility of an asphalt composition, and an aggregate peeling resistance. 35 mass% or less is more preferable, 29 mass% or less is more preferable, and 22 mass% or less is the most preferable.
In addition, content of the block which has a vinyl aromatic monomer unit as a main body can be measured by the method of the Example description later mentioned.

In this embodiment, the content of the vinyl aromatic monomer unit in the copolymer block (B) containing the conjugated diene monomer unit and the vinyl aromatic monomer unit in the polymer is determined by separating the asphalt composition. 10 mass% or more is preferable at the point of stability, heat aging resistance, and the recoverability after tension | pulling. 20 mass% or more is more preferable, 25 mass% or more is further more preferable. Moreover, 60 mass% or less is preferable at the point of the low addition amount of the polymer added to asphalt, the separation stability of an asphalt composition, the softness | flexibility of an asphalt composition or a polymer, a weather resistance, and aggregate peeling resistance, 50 The mass% or less is more preferable. 35 mass% or less is more preferable, and 30 mass% or less is the most preferable.
The vinyl aromatic monomer unit content (RS) in the copolymer block (B) is calculated from the vinyl aromatic monomer unit content (TS) in the polymer. It is obtained by dividing the content (BS) of blocks mainly composed of body units.
Specifically, RS (%) = (TS−BS) / (100−BS) × 100

The content of the short chain vinyl aromatic monomer polymerization portion in the copolymer block (B) in the present embodiment is preferably 50% by mass or more. When the content of the polymer moiety of the short chain vinyl aromatic monomer in the polymer block (B) is within the above range, the compatibility between the polymer and asphalt is high, and the recoverability after tension of the asphalt composition is high. , Heat aging resistance and aggregate peeling resistance are improved. It is 70 mass% or more, More preferably, it is 80 mass% or more, More preferably, it is 90 mass% or more. Although there is no restriction | limiting in particular in an upper limit, it is preferable that it is 100 mass% or less, and it is preferable that it is 99 mass% or less.
Here, the short-chain vinyl aromatic monomer polymerization portion is a component composed of 2 to 6 vinyl aromatic monomer units in the polymer block (B). And content of a short chain vinyl aromatic monomer polymerization part made content of the vinyl aromatic monomer unit in a polymer block (B) 100 mass%, and connected 2-6 pieces in it It is calculated | required as content of a vinyl aromatic monomer unit.

Further, the ratio of two connected vinyl aromatic monomer units is preferably 10% by mass or more and 45% by mass or less, more preferably 13% by mass or more and 42% by mass or less, and still more preferably. It is 19 mass% or more and 36 mass% or less.
The ratio of three linked vinyl aromatic monomer units is preferably 45% by mass or more and 80% by mass or less, more preferably 45% by mass or more and 75% by mass or less, and still more preferably. It is 45 mass% or more and 65 mass% or less.

The content of the short chain vinyl aromatic monomer polymerization portion in the copolymer block (B) is, for example, a conjugated diene monomer and an aromatic vinyl monomer when the copolymer block (B) is polymerized. It is possible to control the addition time and the reactor internal temperature. It can be controlled by any one or combination of the number of additions, addition time, and reactor internal temperature. Increasing the number of times of addition tends to increase the content of the polymer moiety of the short chain vinyl aromatic monomer, and it is preferable to make it twice or more.
Increasing the addition time tends to increase the content of the short chain vinyl aromatic monomer polymerization portion, and is preferably 20 minutes or more and 80 minutes or less. When the reactor internal temperature is increased, the content of the short chain vinyl aromatic monomer polymerization portion tends to increase, and 56 ° C to 90 ° C is preferable.

The polymer used in the present embodiment has substantially no crystallization peak due to the copolymer block (B) in the range of −20 to 80 ° C. in the obtained differential scanning calorimetry (DSC) chart. Is preferred. Here, “there is no crystallization peak due to the copolymer block (B) in the range of −20 to 80 ° C.” means that the crystallization of the copolymer block (B) is performed in this temperature range. A peak due to crystallization does not appear or a peak due to crystallization is observed, but the crystallization peak heat due to the crystallization is preferably less than 3 J / g, more preferably less than 2 J / g, Preferably it is less than 1 J / g, and still more preferably means no crystallization peak heat. In the differential scanning calorimetry (DSC) chart, a polymer having substantially no crystallization peak due to the copolymer block (B) in the range of −20 to 80 ° C. is stored at a high temperature, particularly in the case of an asphalt composition. Good stability and elongation. The polymer having substantially no crystallization peak due to the copolymer block (B) in the range of −20 to 80 ° C. as described above is a vinyl bond amount adjusting agent, a conjugated diene, a vinyl aromatic compound, It is obtained by hydrogenating a base non-hydrogenated polymer obtained by carrying out a polymerization reaction using a regulator for adjusting the random polymerizability.
The crystallization peak temperature and the crystallization peak calorie can be measured using a differential scanning calorimeter.

The hydrogenation rate of the amount of double bonds contained in the conjugated diene monomer unit in the polymer used in this embodiment is low polymer addition amount added to asphalt, recoverability after tension, high heat aging resistance during storage From the viewpoint of aggregate releasability, it is essential to exceed 90 mol% with respect to the total double bond amount before hydrogenation. 93 mol% or more is preferable, 95 mol% or more is more preferable, and 97 mol% or more is more preferable.
Moreover, although there is no restriction | limiting in particular, 100 mol% or less is preferable. Furthermore, from the point of viscosity, 98 mol% or less is preferable, 96 mol% or less is more preferable, and 93 mol% or less is further more preferable. In the present specification, the conjugated diene monomer unit is referred to as a “conjugated diene monomer unit” regardless of before and after hydrogenation.
The hydrogenation rate of the double bond amount can be adjusted by controlling the hydrogenation amount and the hydrogenation reaction time in the hydrogenation step described later. Moreover, a hydrogenation rate can be calculated | required by the method as described in the Example mentioned later.

  The vinyl content in the conjugated diene monomer unit before hydrogenation is preferably 15 mol% or more and 50 mol% or less, more preferably 18 mol% or more and 40 mol% or less, and further preferably 21 mol% or more and 32 mol% or less. Yes, most preferably 24 mol% or more and 30 mol% or less. When the vinyl content in the conjugated diene monomer unit before hydrogenation is 15 mol% or more, the amount of polymer added to the asphalt tends to be low. Moreover, it exists in the tendency for heat aging resistance and a weather resistance to become high because it is 50 mol% or less. Here, “vinyl content” means a conjugated diene monomer unit incorporated in a 1,2-bond, 3,4-bond, and 1,4-bond bond mode of the conjugated diene before hydrogenation. It is set as the ratio of the conjugated diene monomer unit incorporated by the 1, 2- bond and the 3, 4- bond with respect to the total mol amount. The vinyl content can be measured by NMR, specifically by the method described in the examples described later. The distribution of vinyl content in the block mainly composed of conjugated diene monomer units is not limited.

In this embodiment, the melt flow rate (MFR, 230 ° C., 2.16 kgf) of the polymer is preferably 0 g / 10 min or more from the viewpoint of manufacturability. 0.05 g / 10 min or more is more preferable, 0.10 g / 10 min or more is further preferable, and 0.20 g / 10 min or more is most preferable. Moreover, 5 g / 10min or less is preferable at the point of the recoverability after tension | pulling of an asphalt composition, and the anti-aggregation property of an aggregate. 2 g / 10 min or less is more preferable, and 1 g / 10 min or less is more preferable.
In the present embodiment, in the present embodiment of the polymer, the weight average molecular weight (Mw) of the polymer is preferably 50,000 or more in terms of recoverability after tension of the asphalt composition and anti-aggregation resistance. 100,000 or more is more preferable, 150,000 or more is more preferable, and 170,000 or more is most preferable. In terms of manufacturability, it is preferably 320,000 or less, more preferably 280,000 or less, further preferably 260,000 or less, and most preferably 250,000 or less.

In this embodiment, the molecular weight distribution (Mw / Mn) of the polymer (ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn)) is 1.03 or more in terms of the low polymer addition amount added to the asphalt. Is preferred. 1.05 or more is more preferable, 1.11 or more is more preferable, and 1.20 or more is most preferable. Further, in terms of manufacturability and a low polymer addition amount added to asphalt, 2.0 or less is preferable, 1.7 or less is more preferable, 1.4 or less is further preferable, and 1.3 or less is most preferable.
The weight average molecular weight and molecular weight distribution of the polymer can be determined by the method described in the examples described later.
In the present embodiment, the tan δ peak height of 0 ° C. or less obtained from the measurement of the viscoelasticity of the polymer is preferably 0.7 or more in terms of the aggregate peel resistance. 0.8 or more is more preferable, 0.9 or more is more preferable, and 1.0 or more is most preferable. Further, the tan δ peak height of 0 ° C. or less is preferably 2.0 or less from the viewpoint of aggregate peelability. 1.6 or less is more preferable, 1.4 or less is more preferable, and 1.3 or less is the most preferable.

The tan δ peak temperature of the polymer is preferably −70 ° C. or higher from the viewpoint of high compatibility with asphalt. It is more preferably −50 ° C. or higher, and further preferably −40 ° C. or higher. Further, the tan δ peak temperature of the polymer is preferably 0 ° C. or less in view of the flexibility of the asphalt composition, the recovery property after tension, and the anti-aggregation property of the aggregate. It is more preferably −10 ° C. or lower, and further preferably −15 ° C. or lower.
The tan δ peak height and temperature can be determined by the method described in the examples described later.

  By controlling the content ratio of the vinyl aromatic monomer unit and the conjugated diene monomer unit in the copolymer block (B), it has a peak top of tan δ in the range of −70 to 0 ° C. can do. When the ratio of vinyl aromatic monomer units is increased, the peak top of tan δ tends to have a higher temperature, and when the ratio of vinyl aromatic monomer units is decreased, the peak top of tan δ tends to have a lower temperature.

  Moreover, the peak top value can be adjusted to 0.7 or more and 2.0 or less by controlling the temperature and the addition time or number of additions of each monomer in the polymerization of the copolymer block (B). Specifically, a conjugated diene monomer and a styrene monomer added at a constant rate within a reactor internal temperature range of 56 to 90 ° C., a reactor internal pressure range of 0.1 MPa to 0.50 MPa, and the like. The body addition time is within the range of 10 to 60 minutes, or the addition frequency is 3 times or more. As another method, there is a tendency to depend on the temperature during the hydrogenation reaction. In addition to any of the above methods, when the temperature during the hydrogenation reaction is 80 ° C. or more and 120 ° C. or less, the peak top value is 0. There is a tendency to approach 7 or more and 2.0 or less.

(Polymer form)
The bulk density of the polymer of this embodiment before mixing with asphalt is 0.05 g / mL or more in terms of low polymer addition amount added to asphalt, high solubility in asphalt, high workability, transportation cost, etc. Is preferred. 0.10 g / mL or more is more preferable, 0.17 g / mL or more is more preferable, and 0.25 g / mL or more is most preferable. Moreover, 0.45 g / mL or less is preferable at the point of the low polymer addition amount added to asphalt and the high solubility to asphalt. 0.38 g / mL or less is more preferable, 0.35 g / mL or less is more preferable, and 0.30 g / mL or less is most preferable.
The specific surface area of the polymer of the present embodiment before mixing with asphalt is preferably 0.10 m ² / g or more from the viewpoint of a low polymer addition amount added to asphalt and high solubility in asphalt. 0.20m more preferably at least ² / g, more preferably more than ^{0.30m 2 / g, 0.41m 2 /} g or more is most preferred. Moreover, 0.55 m < ² > / g or less is preferable at points, such as the low polymer addition amount added to asphalt, the high solubility to asphalt, high workability | operativity, and transportation cost. 0.52m or less, more preferably ² / g, more preferably from 0.50 m ² / g or less, most preferably 0.48 m ² / g.

[Production method of polymer]
The polymer used in the present embodiment includes a polymerization step in which a polymer is obtained by polymerizing at least a conjugated diene monomer and a vinyl aromatic monomer in a hydrocarbon solvent using a lithium compound as a polymerization initiator. A hydrogenation step of hydrogenating the double bond in the conjugated diene monomer unit of the coalescence and a desolvation step of desolvating the solvent of the solution containing the polymer can be sequentially performed for production.
(Polymerization process)
In the polymerization step, a polymer is obtained by polymerizing a monomer containing at least a conjugated diene monomer and a vinyl aromatic monomer in a hydrocarbon solvent using a lithium compound as a polymerization initiator.

(Hydrocarbon solvent)
The hydrocarbon solvent used in the polymerization step is not particularly limited. For example, aliphatic hydrocarbons such as butane, pentane, hexane, isopentane, heptane, and octane; cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, etc. And aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene. These may be used alone or in combination of two or more.

(Polymerization initiator)
Although it does not specifically limit as a lithium compound used as a polymerization initiator in a superposition | polymerization process, For example, the compound which combined one or more lithium atoms in molecules, such as an organic monolithium compound, an organic dilithium compound, and an organic polylithium compound, is mentioned. . Such an organic lithium compound is not particularly limited. For example, ethyllithium, n-propyllithium, isopropyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, hexamethylenedilithium, butadienyl Examples include dilithium and isoprenyl dilithium. These may be used alone or in combination of two or more.

(Monomer used for polymerization)
The conjugated diene monomer is not particularly limited. For example, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3- Examples thereof include diolefins having a pair of conjugated double bonds such as pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Of these, 1,3-butadiene and isoprene are preferable from the viewpoint of economy. From the viewpoint of mechanical strength, 1,3-butadiene is more preferable. These may be used individually by 1 type and may use 2 or more types together.
Although it does not specifically limit as a vinyl aromatic monomer, For example, styrene, (alpha) -methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N, N-dimethyl-p-aminoethyl styrene, And vinyl aromatic compounds such as N, N-diethyl-p-aminoethylstyrene. Of these, styrene is preferred from the viewpoint of economy. These may be used alone or in combination of two or more.

In addition to the conjugated diene monomer and the vinyl aromatic monomer, other monomers copolymerizable with the conjugated diene monomer and the vinyl aromatic monomer can also be used.
In the polymerization process, adjustment of the polymerization rate, adjustment of the microstructure of the polymerized conjugated diene monomer units (ratio of cis, trans, and vinyl), reaction ratio of conjugated diene monomer and vinyl aromatic monomer A predetermined polar compound or a randomizing agent can be used for the purpose of adjusting the above.

Although it does not specifically limit as a polar compound or a randomizing agent, For example, Ethers, such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether; Amines, such as a triethylamine and tetramethylethylenediamine; Thioethers, phosphines, phosphoramides, alkylbenzene sulfone Examples thereof include acid salts, alkoxides of potassium and sodium.
It does not specifically limit as a polymerization method implemented at a superposition | polymerization process, A well-known method is applicable. Known methods include, for example, Japanese Patent Publication No. 36-19286, Japanese Patent Publication No. 43-17799, Japanese Patent Publication No. 46-32415, Japanese Patent Publication No. 49-36957, Japanese Patent Publication No. 48-2423, and Japanese Patent Publication No. Sho. Examples thereof include methods described in Japanese Patent No. 48-4106, Japanese Patent Publication No. 56-28925, Japanese Patent Application Laid-Open No. 59-166518, Japanese Patent Application Laid-Open No. 60-186777, and the like.

(Deactivation process)
It is preferable to deactivate the active terminal of the polymer by the deactivation step. The method of deactivating the active terminal of the polymer can be achieved by reacting with a compound having an active terminal and active hydrogen. Although the compound which has active hydrogen is not specifically limited, Alcohol and water are preferable at the economical point.

(Hydrogenation process)
The hydrogenation step is a step in which a hydrogenation reaction is performed on a part of the double bond in the conjugated diene monomer unit of the polymer obtained in the polymerization step. The catalyst used in the hydrogenation reaction is not particularly limited. For example, a supported heterogeneous catalyst in which a metal such as Ni, Pt, Pd, or Ru is supported on a support such as carbon, silica, alumina, or diatomaceous earth. A so-called Ziegler-type catalyst using an organic salt such as Ni, Co, Fe, or Cr or an acetylacetone salt and a reducing agent such as organic Al; a so-called organic complex catalyst such as an organometallic compound such as Ru or Rh, or reduction to a titanocene compound Examples of the catalyst include a homogeneous catalyst using organic Li, organic Al, organic Mg, and the like. Among these, a homogeneous catalyst system using organic Li, organic Al, organic Mg, or the like as a reducing agent for the titanocene compound is preferable from the viewpoints of economy, heat aging resistance or weather resistance of the polymer.

The hydrogenation method is not particularly limited. For example, the method described in Japanese Patent Publication No. 42-8704 and Japanese Patent Publication No. 43-6636, preferably Japanese Patent Publication No. 63-4841 and Japanese Patent Publication No. 63-5401. The method described in the gazette is mentioned. Specifically, hydrogenated block copolymer solution can be obtained by hydrogenation in the presence of a hydrogenation catalyst in an inert solvent.
The hydrogenation reaction can be any of a batch process, a continuous process, or a combination thereof.
The hydrogenation reaction is not particularly limited, but is preferably performed after the step of deactivating the active terminal of the polymer described above from the viewpoint of high hydrogenation activity.

  In the hydrogenation step, the conjugated bond of the vinyl aromatic monomer unit may be hydrogenated. The hydrogenation rate of the conjugated bond in all vinyl aromatic monomer units is preferably 30 mol% or less, more preferably 10 mol% or less, and further preferably 3 mol% or less. Further, the lower limit of the hydrogenation rate of the conjugated bond in the all vinyl aromatic monomer is not particularly limited, but is 0 mol%. When the hydrogenation rate of the conjugated bond in the total vinyl aromatic monomer is within the above range, the amount of the polymer added to the asphalt tends to be low or the compatibility with the asphalt tends to be high.

(Desolvation process)
The solvent removal step is a step of removing the solvent of the solution containing the polymer. The solvent removal method is not particularly limited, and examples thereof include a steam stripping method and a direct solvent removal method.
The amount of residual solvent in the polymer obtained by the solvent removal step is preferably 2% by mass or less, more preferably 0.5% by mass or less, still more preferably 0.2% by mass or less, and still more. Preferably it is 0.05 mass% or less, More preferably, it is 0.01 mass% or less. Further, the lower limit of the amount of the residual solvent in the polymer is not particularly limited, but is preferably less, more preferably 0% by mass, but usually 0.01% by mass in terms of economy at the time of solvent removal. This is the range of 0.1% by mass.

From the viewpoint of heat aging resistance of the polymer and suppression of gelation, it is preferable to add an antioxidant. The antioxidant is not particularly limited, and examples thereof include phenolic antioxidants such as radical scavengers, phosphorus antioxidants such as peroxide decomposers, and sulfur antioxidants. Moreover, you may use the antioxidant which has both performances together. These may be used alone or in combination of two or more. Among these, it is preferable to add a phenolic antioxidant from the viewpoint of heat aging resistance of the polymer or asphalt composition and suppression of gelation.
In addition, from the viewpoint of preventing coloring of the polymer and improving mechanical strength, a deashing process for removing metal in the polymer and a neutralization process for adjusting the pH of the polymer, for example, addition of an acid, before the solvent removal process Or carbon dioxide gas may be added.

[Asphalt composition]
<Asphalt>
Asphalts that can be used in the present embodiment include, for example, those obtained as a by-product during petroleum refining (petroleum asphalt), natural products (natural asphalt), or a mixture of these with petroleum. Can be mentioned. Its main component is called bitumen. Specifically, straight asphalt, semi-blown asphalt, blown asphalt, tar, pitch, cutback asphalt to which oil is added, asphalt emulsion and the like can be mentioned. You may mix and use these.
Suitable asphalt includes straight asphalt having a penetration (measured according to JIS-K2207) of preferably 30 or more and 300 or less, more preferably 40 or more and 200 or less, and further preferably 45 or more and 150 or less.

<Asphalt composition>
In the asphalt composition of the present embodiment, the blending ratio of the polymer is 0.5 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of asphalt. The blending ratio of the polymer is preferably 0.5 parts by mass or more and 20 parts by mass or less, more preferably 0.5 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of asphalt.
In this embodiment, arbitrary petroleum resins can be mix | blended as needed. The type of petroleum resin is not particularly limited, but aliphatic petroleum resins such as C5 petroleum resins, aromatic petroleum resins such as C9 petroleum resins, and alicyclic petroleum resins such as dicyclopentadiene petroleum resins. Resins, petroleum resins such as C5 / C9 copolymer petroleum resins, and hydrogenated petroleum resins obtained by hydrogenating these petroleum resins can be used. Although there is no restriction | limiting in particular regarding the quantity of petroleum resin, Preferably it is 1 to 10 mass parts with respect to 100 mass parts of asphalt, More preferably, it is 2 to 6 mass parts.

  In this embodiment, arbitrary additives can be mix | blended as needed. The type of additive is not particularly limited as long as it is generally used for blending thermoplastic resins and rubber-like polymers. For example, calcium carbonate, magnesium carbonate, magnesium hydroxide, calcium sulfate, barium sulfate, silica, clay, talc, mica, wollastonite, montmorillonite, zeolite, alumina, titanium oxide, magnesium oxide, zinc oxide, slug wool, glass fiber Inorganic fillers such as carbon black, pigments such as iron oxide, stearic acid, behenic acid, zinc stearate, calcium stearate, magnesium stearate, ethylene bisstearamide, lubricants, mold release agents, paraffinic process oils, Softeners and plasticizers such as naphthenic process oil, aromatic process oil, paraffin, organic polysiloxane, mineral oil, hindered phenol antioxidant, antioxidant such as phosphorus heat stabilizer, hindered amine light Refining agents, benzotriazole-based UV absorbers, flame retardants, antistatic agents, organic fibers, glass fibers, carbon fibers, metal whiskers and other reinforcing agents, colorants, other additives or mixtures thereof, etc. "(Edited by Rubber Digest, Japan). There is no restriction | limiting in particular regarding the quantity of an additive, Although it can select suitably, Usually, it is 50 mass parts or less with respect to 100 mass parts of asphalt.

There is no particular limitation regarding the method for producing the asphalt composition of the present embodiment. The conditions for stirring the polymer and asphalt mixture are not particularly limited, but can be performed at a temperature of 160 ° C. or higher and 200 ° C. or lower (usually around 180 ° C.). The stirring time is usually 30 minutes to 6 hours, but a shorter one is better in terms of economy. The stirring speed may be appropriately selected depending on the apparatus to be used, but is usually 100 ppm or more and 8,000 rpm or less.
In addition to the polymer of the present embodiment, the asphalt composition is not particularly limited as other polymers. For example, olefins such as natural rubber, polyisoprene rubber, polybutadiene rubber, styrene butadiene rubber, and ethylene propylene copolymer can be used. Elastomers: chloroprene rubber, acrylic rubber, ethylene vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, atactic polypropylene, amorphous polyalphaolefin, and other olefin polymers, and blends of polypropylene and ethylene / propylene copolymers Further, a blend of polypropylene and an ethylene / propylene / diene terpolymer, an olefin-based thermoplastic elastomer which is a copolymer of ethylene or the like may be used in combination.

In view of high heat aging resistance and softening point, it is preferably used in combination with an olefin polymer. Among these, an olefin polymer having at least a propylene unit is preferable. As addition amount, it is preferable to put 5-40 mass parts with respect to 100 mass parts of polymers of this embodiment.
As other block copolymers, the block copolymer (a) is mainly composed of a polymer block (A) mainly composed of at least one vinyl aromatic monomer unit, and at least one conjugated diene monomer unit. The block copolymer (a) comprising the polymer block (C) is preferred. Although a block copolymer (a) is not specifically limited, For example, SIS, SBS, SEBS, and SEPS are preferable. Among these, SBS is preferable from the viewpoint of low temperature elongation.

The phrase “consisting mainly of conjugated diene monomer units” means that the polymer block contains more than 90% by mass of conjugated diene monomer units, preferably 95% by mass or more. Although there is no restriction | limiting in particular in an upper limit, It is preferable that it is 100 mass% or less, and it is preferable that it is 99 mass% or less.
From the viewpoint of good low temperature elongation, the blending ratio of the block copolymer (a) in the total amount of the polymer of the present embodiment and the block copolymer (a) is in the range of 15 to 85% by mass. In addition, the blending amount of the block copolymer (a) is preferably 30% by mass or more, more preferably 50% by mass or more, still more preferably 65% by mass or more, and 75% by mass from the viewpoint of good low-temperature performance and low viscosity. The above is most preferable. In addition, from the viewpoint of high softening point and recoverability after pulling, the blending amount of the block copolymer (a) is preferably 75% by mass or less, more preferably 60% by mass or less, and even more preferably 45% by mass or less, Most preferred is 35% by mass or less.

Further, the structure of the block copolymer (a) is not particularly limited, and examples thereof include structures represented by the following formulas (i) to (vi).
(AB) n (i)
B- (AB) n (ii)
A- (B-A) n (iii)
A- (BA) n-X (iv)
[(AB) k] m-X (v)
[(A−B) k−A] m−X (vi)
(In the above formulas (i) to (vi), A represents a block mainly composed of vinyl aromatic monomer units, B represents a block mainly composed of conjugated diene monomer units, and X represents (Represents a residue of a coupling agent or a residue of a polymerization initiator such as polyfunctional organolithium, and m, n and k represent an integer of 1 or more, preferably an integer of 1 to 5.)

Examples of the polymerization initiator such as the coupling agent or polyfunctional organolithium include, but are not limited to, for example, silicon tetrachloride, tin tetrachloride, epoxidized soybean oil, polyhalogenated hydrocarbon compound, carvone Examples include acid ester compounds, polyvinyl compounds, bisphenol-type epoxy compounds, epoxy compounds, alkoxysilane compounds, halogenated silane compounds, ester compounds, and the like.
The polymer of this embodiment may be a mixture of a coupling body in which X is a residue of a coupling agent and a non-coupling body that does not have X or X is a residue of a polymerization initiator. .

In addition, the block copolymer (a) mentioned here has a styrene content of 20 to 50% by mass, a vinyl bond content of 8 to 60% by mass, and a polystyrene equivalent weight average molecular weight of 100 to 500,000. preferable.
Furthermore, the above formulas (v) and (vi) in which m is 2 or more are more preferable from the viewpoint of the high softening point of the asphalt composition and the high recoverability after pulling.
In addition, when it is necessary to improve the high softening point of the asphalt composition, the resistance of the asphalt composition to the aggregate, the high flow resistance of the asphalt mixture, and the high wear resistance, It is preferable to add a functional group to the coalescence. Examples of the modification method for imparting a functional group include a method in which a modifying agent that generates a functional group-containing atomic group is added to the living terminal of the polymer.

As the element contained in the functional group, oxygen, nitrogen, phosphorus, sulfur, tin, and silicon are particularly preferable.
The functional group is particularly preferably at least one selected from a hydroxyl group, an acid anhydride group, an epoxy group, an amino group, a silanol group, and an alkoxysilane group.
In addition, when giving a branched structure by modification | denaturation reaction, the function as the above-mentioned coupling agent is also fulfilled.
Furthermore, it is preferable to have a functional group containing nitrogen from the viewpoint of resistance to flow rutting. It is more preferable that the functional group is contained in an amount of 2 to 4 mol% in one molecule. Furthermore, it is preferable to contain both a functional group containing nitrogen and a functional group containing oxygen.

  Examples of the modifier include tetraglycidyl metaxylenediamine, tetraglycidyl-1,3-bisaminomethylcyclohexane, tetraglycidyl-p-phenylenediamine, tetraglycidyldiaminodiphenylmethane, diglycidylaniline, γ-caprolactone, γ-glycol. Sidoxyethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriphenoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyldiethylethoxysilane, γ-glycyl Sidoxypropyldimethylethoxysilane, γ-glycidoxypropylmethyldiisopropeneoxysilane, bis (γ-glycidoxypropyl) dimethoxysilane, bis (γ-glycidoxypropyl) dietoki Silane, β- (3,4-epoxycyclohexyl) ethyl-tripropoxysilane, β- (3,4-epoxycyclohexyl) ethyl-tributoxysilane, β- (3,4-epoxycyclohexyl) ethyl-methyldipropoxysilane , Β- (3,4-epoxycyclohexyl) ethyl-methyldibutoxysilane, β- (3,4-epoxycyclohexyl) ethyl-methyldiphenoxysilane, β- (3,4-epoxycyclohexyl) ethyl-dimethylmethoxysilane , Β- (3,4-epoxycyclohexyl) ethyl-diethylethoxysilane, β- (3,4-epoxycyclohexyl) ethyl-dimethylethoxysilane, 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl 2-Imidazolidinone, N, N'-dimethylpropi N'urea, such as N- methylpyrrolidone.

It is recommended that the amount of the modifier used is 0.5 to 5 equivalents relative to 1 equivalent of the living terminal of the polymer.
A radial type polymer containing a functional group is more preferable from the viewpoint of the balance between low viscosity and high softening point.

When it is necessary to improve the solubility of the polymer of this embodiment or other polymers in asphalt, the adhesion resistance of the asphalt composition to the aggregate, the high flow resistance of the asphalt mixture, and the high wear resistance. It is preferable to crosslink.
Examples of the crosslinking agent include sulfur / sulfur compound series, phosphorus series, organic peroxide series, epoxy series, isocyanate series, resin series, amine series, metal chelate series, and thiuram.
Among these, 1 type may be used and 2 or more types may be used. Two or more of the same systems may be used.

The sulfur / sulfur compound system includes elemental sulfur, sulfur chloride, morpholine disulfide, tetramethylthiuram disulfide, selenium dimethyldithiocarbamate, 2- (4′-morpholinodithio) benzothiazole, 4,4′-dithiodimorpholine, Thioacetamide or the like can be used.
As the phosphorus system, phosphoric anhydride (P2O5), polyphosphoric acid, phosphorus oxytrichloride (POCl3), phosphorus trichloride (PCl3), phosphorus pentasulfide (P2S5), or the like can be used.

  Organic peroxide systems include tert-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethyl-2,5-di (t Tributylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5 Di (benzoylperoxy) hexane, 1,1-bis (tertiarybutylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tertiarybutylperoxy) valerate, benzoyl peroxide, Tributyl peroxyisobutyrate can be used.

As the epoxy system, ethylene, normal butyl acrylate, glycidyl methacrylate (glycidyl methacrylate), neopentyl glycol diglycidyl ether, hexanediol diglycidyl ether, trimethylolpropane polyglycidyl ether, hexahydrophthalic acid diglycidyl ester, etc. can be used. .
As the isocyanate system, triallyl isocyanurate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate and the like can be used.

As the resin system, alkylphenol / formaldehyde resin, hexamethoxymethyl / melamine resin and the like can be used.
Examples of amines include hexamethylene diamine, triethylene tetramine, tetraethylene pentamine, hexamethylene diamine carbamate, N, N-dicinnamylidene-1,6-hexane diamine, 4,4-methylene bis (cyclohexylamine) carbamate, 4,4-methylenebis (2-chloroaniline) or the like can be used.
As the metal chelate system, zinc methacrylate, magnesium methacrylate, zinc dimethacrylate, magnesium dimethacrylate and the like can be used.
Among these, sulfur / sulfur compounds and polyphosphoric acid are preferable because of the large effects described above and economical efficiency.

The amount of the crosslinking agent in the asphalt composition of the present embodiment is high in solubility of the polymer and other polymers of the present embodiment in asphalt, adhesion resistance of the asphalt composition to the aggregate, and high flow resistance of the asphalt mixture. In terms of rutting property and high wear resistance, 0.03% by mass or more is preferable. 0.05 mass% or more is more preferable, and 0.10 mass% or more is further more preferable. On the other hand, it is preferably 3% by mass or less from the viewpoint of suppressing generation of toxic gas during production and economical efficiency. 1 mass% or less is more preferable, 0.5 mass% or less is more preferable, and 0.3 mass% or less is the most preferable.
Furthermore, 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane is a coupling agent in terms of the high adhesion resistance of the asphalt composition to the aggregate, the high resistance to rutting, and the high wear resistance. A combination of the polymer having the radial structure used in the above and a sulfur / sulfur compound or polyphosphoric acid is preferred.

The asphalt composition of the present invention can be used in the fields of road pavement, roofing / waterproof sheet, and sealant, and particularly preferably in the field of road pavement. Of these, road pavement is preferred.
The asphalt composition of the present invention can be made into a road pavement mixture by mixing with an appropriate aggregate. The mixing temperature is preferably 90 ° C. to 200 ° C. If the temperature is 90 ° C. or less, it is difficult to uniformly mix the aggregate and the asphalt composition, and if it exceeds 200 ° C., the asphalt composition may be decomposed or crosslinked. It is not preferable. The road pavement mixture of the present invention can be produced at a pavement mixture production site in the same manner as a general pavement mixture, and the mixing and stirring mixer used is either a continuous type or a batch type. Can be used. The mixing method is as follows. First, an aggregate heated to 90 ° C. to 200 ° C. is charged into a mixer, and after kneading for 20 seconds to 30 seconds, the asphalt composition of the present invention heated to the same temperature as the aggregate is charged. A good mixture can be produced simply by mixing for 40 to 60 seconds.

Needless to say, aggregates to be used are applicable to the “Asphalt Pavement Summary” published by the Japan Road Association, regardless of other low-grade aggregates and recycled aggregates. It can use for this invention. For example, in addition to crushed stone, cobblestone, gravel, steel slag, etc., these are similar granular materials, such as artificial sintered aggregate, sintered foam aggregate, artificial lightweight aggregate, ceramic grains, loxobite, aluminum grains, plastic grains, ceramics, Emery, construction waste, fiber, etc. can also be used.
Aggregates are generally roughly classified into coarse aggregates, fine aggregates, and fillers. Coarse aggregates are aggregates that remain on a 2.36 mm sieve, and generally have a particle size range of 2.5 to 5 mm. There are types of crushed stone, No. 6 crushed stone with a particle size range of 5 to 13 mm, No. 5 crushed stone with a particle size range of 13 to 20 mm, and No. 4 crushed stone with a particle size range of 20 to 30 mm. Aggregates obtained by mixing one or more kinds of coarse aggregates having various particle size ranges, synthesized aggregates, and the like can be used. These coarse aggregates may be coated with about 0.3 to 1% by weight of straight asphalt with respect to the aggregates.

The fine aggregate used in the present invention refers to an aggregate that passes through a 2.36 mm sieve and stops on the 0.075 mm sieve. For example, river sand, hill sand, mountain sand, sea sand, crushed sand, fine sand, Examples include screenings, crushed stone dust, silica sand, artificial sand, glass cullet, foundry sand, and recycled aggregate crushed sand.
The filler passes through a 0.075 mm sieve, and is, for example, screening filler content, stone powder, slaked lime, cement, incinerator ash, clay, talc, fly ash, carbon black, etc. In addition, even rubber particles, cork particles, wood particles, resin particles, fiber particles, pulp, artificial aggregates, etc. can be used as fillers as long as they pass through a 0.075 mm sieve. be able to.

The aggregate particle size and the amount of asphalt composition when blended as a road pavement mixture are described in, for example, “Asphalt Pavement Summary”, Japan Road Association, December 1992, page 92, “Types of Asphalt Mixtures”. And the particle size range.
Especially, the mixture for road paving which consists of 2-15 mass% of asphalt compositions and 85-98 mass% of aggregate is preferable, for example.
The polymer of this embodiment can also be used suitably for the composition for asphalt waterproof sheets.
By using the polymer of this embodiment, it is possible to further improve the fatigue rupture resistance, weather resistance, crack resistance at low temperature, misalignment resistance and sag resistance at high temperature, and load resistance of the asphalt waterproof sheet. it can.

  The amount of the polymer of the embodiment is higher than that of the road composition in terms of high flexibility, cracking resistance at lower temperatures, slippage resistance and dripping resistance at higher temperatures, high fatigue flexibility, and weather resistance. The ratio of the polymer is preferably 5% by mass or more with respect to 100% by mass of the total of asphalt and the polymer. 7 mass% or more is more preferable, and 9 mass% or more is further more preferable. On the other hand, it is preferably 20% by mass or less from the viewpoint of manufacturability and economical efficiency of the composition. 17 mass% or less is more preferable, and 14 mass% or less is further more preferable.

In addition to the polymer of the present embodiment, asphalt waterproof sheet compositions include various polymers, tackifiers, softeners, antioxidants, weathering agents, inorganic fillers, lubricants, mold release, as necessary. An agent or a crosslinking agent may be used.
When asphalt waterproof sheets are constructed at room temperature, it is preferable to use asphalt with a high penetration when high low-temperature usability, low viscosity of the composition for asphalt waterproof sheets and high workability are required. . Asphalt having a penetration of 80 or more is preferable. 100 or more is more preferable, 130 or more is more preferable, and 160 or more is most preferable.

When the asphalt waterproof sheet is applied at a high temperature such as a torch method, the penetration of the asphalt waterproof sheet is lower than that when it is applied at room temperature so that the viscosity of the composition for asphalt waterproof sheet is not too low, 30 or more. 150 or less is preferable. 60 or more and 120 or less are more preferable, and 80 or more and 100 or less are preferable.
It is preferable to add a softener when the low-temperature usability of the asphalt waterproof sheet, the low viscosity of the asphalt waterproof sheet composition, and high workability are required. In view of the magnitude of the effect, oil is preferable. Process oil is more preferred.
Moreover, you may use an inorganic filler as needed.
Examples of the construction method of the asphalt waterproof sheet include a thermal method, a torch method, a self-adhesion method, and a composite method. Since the composition for asphalt waterproof sheets using the polymer of the embodiment has high heat aging resistance, it can be suitably used for a heat method or a torch method.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples at all. The measuring method regarding the polymer and asphalt composition in an Example and a comparative example is as follows.
<Content of vinyl aromatic monomer unit in polymer (styrene content)>
Dissolve a certain amount of polymer in chloroform and use a UV spectrophotometer (manufactured by Shimadzu Corporation, UV-2450) to obtain a calibration curve from the peak intensity of the absorption wavelength (262 nm) due to the vinyl aromatic compound (styrene). The content of vinyl aromatic monomer units (styrene) was calculated using this.

<Content of polymer block (A) in polymer>
Using a polymer before hydrogenation, I. M. Kolthoff, etal. , J .; Polym. Sci. 1, p. 429 (1946). For decomposition of the polymer, an osmium acid 0.1 g / 125 mL tertiary butanol solution was used.

<Vinyl content and hydrogenation rate in polymer>
The vinyl content in the partially hydrogenated block copolymer and the hydrogenation rate of unsaturated groups in the conjugated diene were measured by nuclear magnetic resonance spectral analysis (NMR) under the following conditions.
The partially hydrogenated block copolymer was precipitated and recovered by precipitation in a large amount of methanol in the reaction solution after the hydrogenation reaction. Subsequently, the partially hydrogenated block copolymer was extracted with acetone, and the extract was vacuum-dried and used as a sample for 1H-NMR measurement. The conditions for 1H-NMR measurement are described below. The vinyl bond amount and the hydrogenation rate were both measured using a polymer sample after the hydrogenation reaction.

(Measurement condition)
Measuring instrument: JNM-LA400 (manufactured by JEOL)
Solvent: Deuterated chloroform Measurement sample: Extracted sample before and after hydrogenation of polymer Sample concentration: 50 mg / mL
Observation frequency: 400 MHz
Chemical shift criteria: TMS (tetramethylsilane)
Pulse delay: 2.904 seconds Number of scans: 64 times Pulse width: 45 °
Measurement temperature: 26 ° C

<Weight average molecular weight, molecular weight distribution>
The measurement was performed by GPC [apparatus made by Waters], tetrahydrofuran was used as a solvent, and the temperature was measured at 35 ° C. The weight average molecular weight (polystyrene equivalent molecular weight) and the number average molecular weight obtained using a calibration curve (created using the standard molecular weight of standard polystyrene) obtained from the measurement of commercially available standard polystyrene. The molecular weight distribution was determined from the ratio.

<Content of short-chain vinyl aromatic monomer polymerization portion (short-chain styrene content)>
Oxidation decomposition was performed by passing oxygen at a concentration of 1.5% (O3) through a dichloromethane solution of the polymer at 150 mL / min, and the obtained ozonide was dropped into diethyl ether mixed with lithium aluminum hydride and reduced. . Next, pure water was added dropwise for hydrolysis, potassium carbonate was added, salted out, and filtered to obtain a vinyl aromatic hydrocarbon component. This vinyl aromatic hydrocarbon component was measured by GPC. By calculating the area ratio of the peaks obtained here (peak area corresponding to short chain vinyl aromatic monomer polymerization portion / total area of peaks), the short chain vinyl aromatic monomer polymerization portion in the polymer The content of was obtained. The ozone generator uses OT-31R-2 type manufactured by Japan Ozone Co., Ltd., and GPC measurement uses 2487 manufactured by Waters, using chloroform as a solvent, a flow rate of 1.0 mL / min, and a column oven at 35 ° C. Two columns, Shodex column-K803L, were connected for measurement.

<Tan δ (loss tangent) peak height, temperature>
The tan δ (loss tangent) peak height and temperature were determined by measuring the viscoelastic spectrum using a viscoelasticity measuring / analyzing apparatus ARES (trade name, manufactured by TA Instruments Japan Co., Ltd.). Measurement materials were set in a twist type geometry, and the measurement was performed at a strain of 0.5% and a measurement frequency of 1 Hz.

<Bragg spacing>
Measurement was performed using a nanoscale X-ray structure evaluation apparatus NANO-Viewer [apparatus made by Rigaku] and PILATUS100K (two-dimensional semiconductor detector). A two-dimensional SAXS pattern obtained by PILATUS100K was subjected to background and empty cell scattering correction, and then a one-dimensional scattering profile was obtained by taking an annular average. The scattering primary peak position (2θm) derived from the microphase separation structure was read from the one-dimensional scattering profile, and the inter-domain distance d was calculated by Bragg's equation (1).
d = λ / 2 / sin (θm) (1) θm: Bragg angle of the scattered primary peak position

<Preparation of hydrogenation catalyst>
A reaction vessel purged with nitrogen was charged with 2 liters of dried and purified cyclohexane, and 40 mmol of bis (η5-cyclopentadienyl) titanium di- (p-tolyl) and 1,2-polybutadiene having a molecular weight of about 1,000 (1 , 2-vinyl bond amount of about 85%) After dissolving 150 grams, a cyclohexane solution containing 60 mmol of n-butyllithium was added and allowed to react at room temperature for 5 minutes, and immediately 40 mmol of n-butanol was added and stirred at room temperature. Saved with.

<Polymer polymerization method>
(Polymer 1)
Using a jacketed tank reactor, a predetermined amount of cyclohexane was charged into the reactor, and the temperature inside the reactor was adjusted to 60 ° C. Thereafter, n-butyllithium was added from the bottom of the reactor so as to be 0.12 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor). Further, a cyclohexane solution of N, N, N ′, N′-tetramethylethylenediamine was added to 0.40 mol with respect to 1 mol of n-butyllithium. Thereafter, as a monomer, as a polymerization reaction in the first step, a cyclohexane solution containing 10 parts by mass of styrene (monomer concentration: 15% by mass) was supplied in about 10 minutes, and the temperature in the reactor was adjusted to 65 ° C. The reaction was allowed to proceed for 15 minutes after the supply was stopped.

Next, as a polymerization reaction in the second step, a cyclohexane solution containing 57 parts by mass of butadiene (monomer concentration of 15% by mass) and a cyclohexane solution containing 23 parts by mass of styrene (monomer concentration of 15% by mass) were taken over 60 minutes. The reaction was continuously supplied to the reactor at a constant rate, the specific energy was adjusted to 0.30 kw / m ³ , the reaction was carried out at an internal pressure of 0.30 MPa, and the reaction was continued for 15 minutes after the supply was stopped.
Next, as a polymerization reaction in the third step, a cyclohexane solution containing 10 parts by mass of styrene (monomer concentration: 15% by mass) was supplied in about 10 minutes, and the temperature in the reactor was adjusted to 65 ° C. The reaction was allowed to proceed for 15 minutes after the supply was stopped.
Next, 100 ppm of the above hydrogenation catalyst as titanium with respect to the mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C. After completion of the reaction, an aqueous methanol solution was added, and then octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added in an amount of 0.1% by mass based on the mass of the polymer. .
The obtained polymer structure is shown in Table 1.

(Polymer 2)
n-Butyllithium is added from the bottom of the reactor so as to be 0.085 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set to The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 58 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 20 parts by mass (monomer concentration 15% by mass), the specific energy was adjusted to 0.35 kw / m ³ , and the third step was a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass). The polymer was polymerized in the same manner as the polymer 1 except that 95 ppm of the hydrogenation catalyst was added.

(Polymer 3)
n-Butyllithium is added from the bottom of the reactor so as to be 0.125 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 45 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 33 parts by mass (monomer concentration of 15% by mass), the specific energy was adjusted to 0.25 kw / m ³ , and the third step was a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration of 15% by mass). Polymerization was carried out in the same manner as for the polymer 1 except that.

(Polymer 4)
n-Butyllithium is added from the bottom of the reactor so as to be 0.115 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is adjusted. The first step is a cyclohexane solution containing 18 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 50 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 14 parts by mass (monomer concentration 15% by mass), the specific energy was adjusted to 0.32 kw / m ³ , and the third step was a cyclohexane solution containing 18 parts by mass of styrene (monomer concentration 15% by mass). Polymerization was carried out in the same manner as for the polymer 1 except that.

(Polymer 5)
n-Butyllithium is added from the bottom of the reactor so as to be 0.125 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 20% by mass), and the second step is a cyclohexane solution containing 57 parts by mass of butadiene (monomer concentration 20% by mass) and styrene. A cyclohexane solution containing 21 parts by mass (monomer concentration of 20% by mass) was supplied in three portions every 15 minutes, the specific energy was adjusted to 0.32 kw / m ³ , and the third step was 11 parts by mass of styrene. Polymerization was carried out in the same manner as for the polymer 1 except that the solution was a cyclohexane solution (monomer concentration 20% by mass).

(Polymer 6)
The first step is a cyclohexane solution (monomer concentration 25% by mass) containing 10 parts by mass of styrene, and the second step is a cyclohexane solution (monomer concentration 25% by mass) containing 60 parts by mass of butadiene and 21 parts by mass of styrene. A cyclohexane solution containing (monomer concentration 25% by mass) was added over 10 minutes, the specific energy was adjusted to 0.32 kw / m ³ , and the third step was a cyclohexane solution containing 9 parts by mass of styrene (monomer concentration 25 Polymerization was carried out in the same manner as in Polymer 1 except that the content was changed to (mass%).

(Polymer 7)
n-Butyllithium is added from the bottom of the reactor so as to be 0.125 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 57 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 21 parts by mass (monomer concentration 15% by mass) was continuously supplied to the reactor at a constant rate over 55 minutes, the specific energy was adjusted to 0.32 kw / m ³ , and the reactor internal pressure was 0 The reaction is carried out at 25 MPa, and the third step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 1 Except that the mass%) was polymerized in the same manner as Polymer 1.

(Polymer 8)
n-Butyllithium is added from the bottom of the reactor so that it becomes 0.130 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The first step is a cyclohexane solution containing 8 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 50 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 35 parts by mass (monomer concentration of 15% by mass) was continuously supplied to the reactor at a constant rate over 60 minutes, the specific energy was adjusted to 0.08 kw / m ³ , and the reactor internal pressure was 0 The reaction is carried out at 32 MPa, and the third step is a cyclohexane solution containing 7 parts by mass of styrene (monomer concentration 15 quality). %) Except that as was polymerized in the same manner as Polymer 1.

(Polymer 9)
n-Butyllithium is added from the bottom of the reactor so that it becomes 0.140 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is adjusted. The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 59 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 19 parts by mass (monomer concentration of 15% by mass) was continuously supplied to the reactor at a constant rate over 55 minutes, the specific energy was adjusted to 0.09 kw / m ³ , and the reactor internal pressure was 0 The reaction is carried out at 25 MPa, and the third step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 1 Except that the mass%) was polymerized in the same manner as Polymer 1.

(Polymer 10)
n-Butyllithium is added from the bottom of the reactor so as to be 0.085 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set to The first step is a cyclohexane solution containing 17 parts by mass of styrene (monomer concentration: 15% by mass), the temperature in the reactor is 53 ° C., and the second step is a cyclohexane solution containing 43 parts by mass of butadiene. A cyclohexane solution (monomer concentration: 15% by mass) containing (monomer concentration: 15% by mass) and 24 parts by mass of styrene is continuously supplied to the reactor at a constant rate over 55 minutes, and the specific energy is 0.42 kw / m ^3. And the reaction was carried out at a reactor internal pressure of 0.15 MPa. The third step was a cyclohexane containing 16 parts by mass of styrene. Except that the acid solution (monomer concentration 15 wt%) was polymerized in the same manner as Polymer 1.

(Polymer 11)
n-Butyllithium is added from the bottom of the reactor so that it becomes 0.080 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The first step is a cyclohexane solution containing 10 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 57 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 24 parts by mass (monomer concentration 15% by mass), the specific energy was adjusted to 0.35 kw / m ³ , and the third step was a cyclohexane solution containing 9 parts by mass of styrene (monomer concentration 15% by mass). And polymerized in the same manner as the polymer 1 except that 85 ppm of the hydrogenation catalyst was added.

(Polymer 12)
n-Butyllithium is added from the bottom of the reactor so as to be 0.085 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set to The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 58 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 20 parts by mass (monomer concentration 15% by mass), the specific energy was adjusted to 0.39 kw / m ³ , and the third step was a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass). And polymerized in the same manner as the polymer 1 except that the hydrogenation reaction was not performed.

(Polymer 13)
The first step is a cyclohexane solution containing 17 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a constant cyclohexane solution containing 67 parts by mass of butadiene (monomer concentration 15% by mass) over 60 minutes. The reactor is continuously fed to the reactor at a speed, reacted for 15 minutes after the supply is stopped, and the third step is a cyclohexane solution containing 16 parts by mass of styrene (monomer concentration 15% by mass), except that no hydrogenation reaction is performed. Polymerization was conducted in the same manner as in Polymer 1.

(Polymer 14)
n-Butyllithium was added from the bottom of the reactor to 100 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature was adjusted. The second step is a cyclohexane solution containing 60 parts by mass of butadiene (monomer concentration 15% by mass) and a cyclohexane solution containing 20 parts by mass of styrene (monomer concentration 15% by mass) at a constant rate over 57 minutes. Polymerization was conducted in the same manner as in Polymer 1 except that the specific energy was continuously adjusted to 0.42 kw / m ³ by supplying the reactor to the reactor.

(Polymer 15)
n-Butyllithium is added from the bottom of the reactor so that it becomes 0.080 parts by mass with respect to 100 parts by mass of all monomers (the total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set. The second step is a cyclohexane solution containing 60 parts by mass of butadiene (monomer concentration 15% by mass) and a cyclohexane solution containing 20 parts by mass of styrene (monomer concentration 15% by mass) at a constant rate over 59 minutes. Polymerization was conducted in the same manner as in Polymer 1 except that the specific energy was continuously adjusted to 0.46 kw / m ³ while being supplied to the reactor.

(Polymer 16)
n-Butyllithium is added from the bottom of the reactor so as to be 0.085 parts by mass with respect to 100 parts by mass of all monomers (total amount of butadiene monomer and styrene monomer charged into the reactor), and the polymerization temperature is set to The first step is a cyclohexane solution containing 11 parts by mass of styrene (monomer concentration 15% by mass), and the second step is a cyclohexane solution containing 59 parts by mass of butadiene (monomer concentration 15% by mass) and styrene. A cyclohexane solution containing 20 parts by mass (monomer concentration: 15% by mass) was used, and the specific energy was adjusted to 0.35 kw / m ³ for polymerization. Thereafter, 1,3-dimethyl-2-imidazolidinone was added to 0.95 mol with respect to 1 mol of n-butyllithium and allowed to react for 25 minutes.
Next, polymerization was performed in the same manner as in Polymer 1 except that 95 ppm of a hydrogenation catalyst was added to the obtained polymer.

<Preparation of asphalt composition>
500 g of straight asphalt 60-80 [manufactured by Shin Nippon Oil Co., Ltd.] was put into a 750 mL metal can, and the metal can was sufficiently immersed in an oil bath at 180 ° C. Next, while stirring 100 parts by mass of melted asphalt at a rotational speed of 4000 rpm, 3.5% by mass of a polymer was added and stirred for 90 minutes after the addition to prepare an asphalt composition.
Moreover, in the addition process of the said polymer, the polymer 2 and SBS were added by the compounding ratio 40 mass parts / 60 mass parts, and then stirred for 180 minutes, and the asphalt composition of Examples 12 and 13 was manufactured. .
Further, the polymer 2 and SBS were added at a blending ratio of 60 parts by weight / 40 parts by weight, and thereafter, the same method as in Examples 12 and 13 was made to produce the asphalt composition of Example 14.
For Examples 12, 13, and 14, the following SBS was used.
Example 12: Kraton D 1184, radial type polymer, styrene content 30%, diblock content 14.5%, weight average molecular weight in terms of polystyrene of 400,000 Example 13, 14: Kraton D 1101, linear polymer The styrene content is 31%, the diblock content is 17.0%, and the weight average molecular weight is 180,000 in terms of polystyrene.

<Adjustment of road pavement mixture>
Examples 1 to 5, Reference Examples 6 to 8, Example 9, Reference Example 10, Examples 11 to 14, and the asphalt compositions and aggregates obtained in Comparative Examples 1 to 5 were used in an experimental capacity of 27 liters. A total amount of 10 kg of the mixture was mixed using a mixer equipped with a heating device, and the road pavement mixture of the present invention was obtained as a dense particle type mixture. The aggregates used were crushed stone and crushed sand in Iwafune-cho, Shimotsuga-gun, Tochigi Prefecture, fine sand in Sakae-machi, Inba-gun, Chiba Prefecture, and stone powder in Yamagata-machi, Sano City, Tochigi Prefecture. Table 2 below shows the particle size distribution of the aggregate used in the mixture.

  Mixing was performed according to the following procedure. That is, first, 94.5 parts by mass of a fine-grained aggregate with a predetermined particle size was put into a mixer and kneaded for 25 seconds, and then 5.5 parts by mass of the asphalt composition obtained in Example 1 was mixed with the mixer. And then kneaded for 50 seconds to obtain a dense particle type road pavement mixture. The mixing temperature was 177 ° C. for both the empty kneading and the main kneading.

<Characteristics of asphalt composition>
Each physical property of the asphalt composition was measured by the following method, and the results are shown in Table 3.
(Recoverability after tension)
The asphalt composition produced by the above method is poured into a special jig to create a specimen. Pulled at a rate of 5 cm / min in a 25 ° C. water bath, stopped when stretched by 20 cm, allowed to stand for 5 minutes, and cut at the center. Thereafter, the specimen was left in the water tank for 60 minutes to measure how much the specimen returned to its original length. It is better that the recoverability after tension is higher, and ◎, ○, Δ, and × are in order from the best.
80% or more: ◎
75% or more and less than 80%: ○
70% or more and less than 75%: △
Less than 70%: ×

(Heat aging resistance of polymer)
The asphalt composition containing 3.5% by mass of the polymer produced by the above method was stored at 190 ° C., sampled after a predetermined time, and the change in the molecular weight distribution of the polymer was analyzed by GPC.
Due to the thermal degradation of the polymer, the peak height of the polymer obtained by GPC is lowered. The smaller the change in the peak height of the polymer before storage, the better the heat aging resistance. The evaluation is based on the number of days when the height change is 30% or more.
2 days or more: ○
1 day or more and less than 2 days: △
Less than 1 day: ×

(Aggregate resistance)
Make a fine-grained mixture by the above <Adjustment of road pavement mixture>, put the specimen for Marshall stability into the Los Angeles tester, rotate the drum 300 times without using steel balls, (Aggregate peelability) is measured. Aggregate resistance to peeling is better as low as possible, ◎, ○, Δ, × from the good order.
Less than 20%: ◎
20% or more and less than 23%: ○
23% or more and less than 26%: △
26% or more: ×

(Processability)
The above-mentioned <Adjustment of the mixture for road paving> is used to create a dense-grained mixture and evaluate the ease of spreading when constructed. It is better to spread the floor more easily.
Easy to spread: ◎
Above and below: ○
Loss of fluidity and difficult to spread: ×

(Low temperature elongation)
In accordance with JIS-K2207, the asphalt composition containing 3.5% by mass of the polymer 1-16 produced by the above method, or the total content of the polymer 2 and SBS in Examples 12-14 is 3. The elongation of the asphalt composition to be 5% by mass was measured.
A standard asphalt sample was pulled in water at 5 ° C. at a rate of 5 ° C./min, and the length (cm) until the sample broke was measured.
The higher the value, the higher the low-temperature performance was judged.
20cm or more: ○
10cm or more: △
Less than 10 cm: ×

(Dynamic stability)
As the aggregate, a mixing ratio of 36/19/27/12/6% of No. 6 crushed stone / No. 7 crushed stone / sand crushed / fine sand / stone powder was used, and 5.5 parts by weight of asphalt composition, 94.5 parts by weight of aggregate. In this section, except for mixing at 180 ° C., a dense particle mixture was prepared according to the above <Preparation of road pavement mixture> and carried out in accordance with Test Method Manual B003. A small rubber wheel loaded on a specimen of a predetermined size was repeatedly reciprocated at a specified temperature, specified time, and specified speed, and the dynamic stability (times / mm) was determined from the amount of deformation per unit time.
It was judged that the higher the value, the higher the rutting resistance, and ◎, ○, Δ, and × from the good order.
20000 times / mm or more: ◎
10,000 times / mm or more: ○
5000 times / mm or more: △
Less than 5000 times / mm: ×

[Examples 1-5, Reference Examples 6-8, Example 9, Reference Example 10, Examples 11-14 ], [Comparative Examples 1-5]
Table 3 shows the evaluation results of Examples 1 to 5, Reference Examples 6 to 8, Example 9, Reference Example 10, Examples 11 to 14, and Comparative Examples 1 to 5, respectively. From Table 3 below, it can be seen that the polymer of the present invention has high recoverability after tension of the asphalt composition, high heat aging resistance during storage, and high aggregate peel resistance.

  The asphalt composition containing the polymer of the present invention can be used in the fields of road paving, roofing / waterproof sheets, and sealants, and particularly preferably in the field of road paving.

Claims (7)

A polymer comprising a conjugated diene monomer unit and a vinyl aromatic monomer unit;
The polymer has a polymer block (A) mainly composed of a vinyl aromatic monomer unit, and a copolymer block (B) containing a conjugated diene monomer unit and a vinyl aromatic monomer unit. ,
The content of the vinyl aromatic monomer unit in the polymer block (A) is 90% by mass or more,
The content of vinyl aromatic monomer units in the copolymer block (B) is 10% by mass or more and 60% by mass or less,
The content of the polymer block (A) is 20% by mass or more and 40% by mass or less,
The distance between the Bragg surfaces of the polymer is 27 nm or more and 48 nm or less,
The hydrogenation rate of double bonds in the conjugated diene monomer unit exceeds 90 mol%,
A polymer having a tan δ peak height of 0 ° C. or lower obtained from viscoelasticity measurement of 0.8 or more and 1.4 or less. The polymer according to claim 1, wherein the content of the vinyl aromatic monomer unit is 20% by mass or more. In the co-polymer block (B), relative to the content 100 wt% of a vinyl aromatic monomer unit, the short chain vinyl aromatic monomer weight consisting of 2-6 vinyl aromatic monomer unit The polymer according to claim 1 or 2 , wherein the content of the combined portion is 50% by mass or more. The polymer of Claim 3 whose content of the said short chain vinyl aromatic monomer polymerization part is 70 mass% or more. The polymer according to any one of claims 1 to 4 , which has a functional group. An asphalt composition comprising 0.5 to 50 parts by mass of the polymer according to any one of claims 1 to 5 and 100 parts by mass of asphalt. The total amount of the polymer according to any one of claims 1 to 5 and the block copolymer (a) is 0.00.
5 parts by weight or more and 50 parts by weight or less;
An asphalt composition containing 100 parts by weight of asphalt,
The block copolymer (a) is a polymer block (A) mainly composed of at least one vinyl aromatic monomer unit, and a polymer block (C) mainly composed of at least one conjugated diene monomer unit. Consists of
The asphalt composition whose content of the said block copolymer (a) in the said total amount is 15-85 mass%.