TWI422635B - Modified block composition for modified asphalt, a method for producing the same, and a bituminous composition - Google Patents

Description

Block copolymer composition for modified asphalt, method for producing the same, and asphalt composition

The present invention relates to 1) a block polymer for modified asphalt and a specific structure of an aromatic vinyl compound, or a block (co)polymer of the compound and a conjugated diene, in particular, a modified asphalt The block (co)polymer is excellent in solubility to straight asphalt, and is superior in torsional strength to a block copolymer composition for modified asphalt, 2) the composition a method for producing the material, and 3) blending the block copolymer composition for the modified asphalt described above with straight-run asphalt, or straight-run asphalt, aromatic hydrocarbon resin and/or heavy oil for storage The phase separation stability (hereinafter referred to as "storage stability") is excellent in workability and low in viscosity, and is excellent in handling property, softening point, ductility, and toughness (tenacity). The asphalt binder is excellent in physical properties, and in recent years, an asphalt composition excellent in torsional strength which is urgently to be solved, for example, is suitable for high viscosity modification of drainage/low noise paving. A composition for asphalt.

In addition, since asphalt is inexpensive and easy to obtain, it is widely used for asphalt roads, waterproof roads, soundproof sheets, and shockproof materials. However, straight-run asphalt is poor in strength, softening point, penetration, and the like.

Furthermore, it has emerged with the improvement of the fine system in the petroleum refining process. There are several new problems, such as a decrease in the performance of the asphalt composition caused by further deterioration of the straight-run asphalt, and stability during storage due to long-term storage of the asphalt composition. The stability at the time of storage refers to the performance, for example, the overall decrease in the softening point, and the phase separation occurs during storage, and the difference in performance between the upper layer and the lower layer occurs. This phenomenon has not been solved until now and has become a big problem.

With the increase of road traffic vehicles or the speed of vehicles, there is a need for more excellent strength for high-traffic roads or highways, and the need to maintain high wear resistance, and the improvement of drainage, or the sound of the sound For the purpose of reduction, for the asphalt road with high voidage, the demand for high-performance asphalt composition (asphalt cement for drainage pavement) is also increased, and it is required to have high softening point and toughness. Mechanical strength.

In order to improve such problems, attempts have been made to add modified asphalts of various copolymer compositions.

Specific examples of such various copolymer compositions include styrene-butadiene random copolymer latex (SBR latex), ethylene-vinyl acetate copolymer (EVA), ethylene- Ethyl acrylate copolymer and the like. However, due to the addition of such copolymers, although considerable improvements have been made in terms of toughness, softening point, and ductility, further improvements are still needed because they are not perfect.

For the further improvement of the softening point and ductility, there has been an attempt to modify the pitch by adding a block copolymer (SB block copolymer) of an aromatic vinyl compound and a conjugated diene.

For example, in order to improve various physical properties of asphalt, various kinds of ether compounds or tertiary amine compounds have been used as a microstructure control agent, and an organolithium compound is added as an initiator. Proposal for a pitch composition of a block copolymer having a specific structure (Patent Document 1 and Patent Document 2). That is, there are disclosed by linear ABA type block copolymer, (AB) _n X type radial alone block copolymer, or in combination of modified bitumen quality.

However, in these publications, although the physical properties of the binder such as the softening point and the toughness of the asphalt can be improved to a considerable extent, the storage stability at a high temperature is not necessarily sufficient.

In this case, there has been a report in recent years that it is possible to obtain a pitch excellent in balance such as ductility and toughness by using a block copolymer in which the content of the aromatic vinyl compound is limited to a predetermined range. Composition (Patent Document 3, Patent Document 4).

In addition, there is a report of a pitch composition having excellent phase separation property and solubility by using a block copolymer copolymerized with a specific coupling agent (Patent Document 5).

However, in these publications, the balance of properties such as asphalt solubility, storage stability, ductility, toughness, and softening point is not sufficient.

In addition, a block copolymer having an excellent storage stability can be produced by using a block copolymer in which the structure of the aromatic vinyl compound and the conjugated diene is limited to a predetermined range (Patent Document 6 and Patent Literature) 7. Patent Document 8).

However, in this disclosed example, since the molecular weight is increased, the melt viscosity is higher and the workability is deteriorated, which is difficult in workability. . It is generally desired to develop an asphalt composition which is excellent in balance of such physical properties and excellent in workability.

At present, a method of increasing the softening point and the toughness by the high molecular weight of the block copolymer or increasing the amount of addition to the pitch to ensure the balance with the ductility is generally employed.

However, according to this method, the solubility of the block copolymer in the pitch is remarkably lowered to elongate the dissolution time, and the melt viscosity of the obtained pitch is remarkably increased, with the result that the workability is deteriorated. In order to solve the problem, it has been reported that a block copolymer having excellent solubility can be produced by using a SB block copolymer having a predetermined bulk density, particle diameter, and pore volume (Patent Document 9).

In addition, in recent years, due to the heavy traffic congestion caused by the increase in the weight of trucks, tank trucks, etc., the wiping torque on the road surface caused by the small radius rotation at the intersection, the call station, etc. The cornering force at the time of cornering and the braking force at the start of the brake may cause a shearing force larger than that during normal driving. Therefore, it is a problem that the damage of the asphalt pavement near the intersection, especially the rutting of the drainage asphalt road or the scattering of the aggregate material, becomes a problem. However, the improvement in the strength (torsion strength) of the end turning is not sufficient, and there is still room for improvement.

Therefore, at present, attempts to modify using the SB block copolymer as described above have not yet yielded satisfactory results, and an excellent solubility to pitch, toughness of the pitch, softening point, and A copolymer for reforming which has a good balance of ductility and excellent torsional strength.

Patent Document 1: Japanese Patent Publication No. Sho 47-17319

Patent Document 2: Japanese Patent Publication No. 59-36949

Patent Document 3: Japanese Patent Laid-Open No. 1-254768

Patent Document 4: Japanese Patent Special Fair No. 5-420

Patent Document 5: Japanese Patent Laid-Open No. Hei 8-225711

Patent Document 6: Japanese Patent Laid-Open No. Hei 6-41439

Patent Document 7: Japanese Patent Laid-Open No. Hei 9-12898

Patent Document 8: Japanese Patent Laid-Open No. Hei 10-212416

Patent Document 9: Japanese Patent Laid-Open No. Hei 11-315187

The present invention is excellent in the solubility of the asphalt by the precise control of the molecular structure, and the asphalt having excellent storage stability, low melt viscosity and excellent torsional strength at the high temperature when the asphalt composition is formed The modifier is intended to provide an asphalt composition for use in road paving, particularly for drainage paving, waterproof sheets, and the like.

In order to develop a pitch composition having the above properties, the present inventors have found that a modified pitch block containing an aromatic vinyl compound having a specific range and a conjugated diene in a specific range has been found. a copolymer, and an aromatic vinyl compound having a structure of a specific range, or a pitch composition of a block (co)polymer of the compound and a conjugated diene The present invention has finally been completed by the fact that it can exhibit very excellent performance and can reach the purpose of costing the invention.

That is, the block copolymer composition for modified pitch of the present invention is characterized in that (a) is a polymer block mainly composed of at least two aromatic vinyl compounds, and at least one conjugated diene is used. The polymer block of the main body is a copolymer, and the content of the fully linked aromatic vinyl compound in the block copolymer is 10 to 50% by weight, and the standard polymerization is determined by gel permeation chromatography (GPC). a block copolymer having a peak molecular weight of from 100,000 to 500,000 in terms of styrene, and (b) one or more aromatic vinyl compound polymer blocks as an essential unit, and may contain one or more conjugates in this unit. a block (co)polymer of a diene as a main polymer block, and a standard polystyrene-converted peak molecular weight measured by gel permeation chromatography (GPC) at (a) a peak of the block copolymer A block (co)polymer having a molecular weight of 1/3 or less is contained in a ratio of (a)/(b) (weight ratio) = 95 to 70/5 to 30.

Here, in the present invention, the "peak molecular weight" means the molecular weight at the peak end, and the same applies hereinafter.

Here, the (a) block copolymer is preferably a general formula (I); (SB) _n -X [in the general formula (I), S represents a polymer block mainly composed of an aromatic vinyl compound, B represents a polymer block mainly composed of a conjugated diene, and n is an integer of 3 or more, and X is a coupling residue. ] indicated.

Further, it is preferred that the (a) block copolymer has a fully bonded aromatic vinyl compound content of from 20 to 45% by weight, and ethylenic linkage in a polymer block mainly composed of a conjugated diene. In the range of 10 to 40 weight%. And (b) the block (co)polymer has a fully bonded aromatic vinyl compound content of 10% by weight or more to 100% by weight, and the ethylene bond content in the polymer block B mainly composed of a conjugated diene At 10 to 50% by weight.

Further, (a) a block copolymer having a peak molecular weight of 10,000 to 25,000 as a polymer block mainly composed of an aromatic vinyl compound of a block copolymer, and (b) a block (co)polymerization by (b) The aromatic vinyl compound as the main polymer block has a peak molecular weight of 5,000 to 50,000.

Further, it is preferred that (a) the polymer block mainly composed of the aromatic vinyl compound of the block copolymer has a peak molecular weight of 10,000 to 20,000 block copolymers, and the total peak molecular weight of the whole is from 130,000 to 400,000.

Further, it is preferred that (b) the polymer block having the aromatic vinyl compound of the block (co)polymer as a main component has a peak molecular weight of 5,000 to 30,000, and the total molecular weight of the polymer block is 5,000 to 60,000, and the overall peak molecular weight is 5,000 to 80,000.

Further, it is preferred that the peak molecular weight of the (b) block (co)polymer measured by gel permeation chromatography (GPC) is equivalent to less than 1/80 of the peak molecular weight of the (a) block copolymer. 1/(n+1) [n is (a) the number of polymer blocks mainly composed of an aromatic vinyl compound in the block copolymer].

Next, the method for producing a block copolymer composition for modified pitch of the present invention comprises (a) a block copolymer, and (b) a block (co)polymer, which is an organic lithium in an inert hydrocarbon solvent. The compound is used as an initiator to polymerize and mix separately according to solution polymerization. Each polymer solution is obtained and homogenized and desolvated to the manufacturer.

Next, the asphalt composition of the present invention (hereinafter referred to as "asphalt composition (1)") is a composition of the above block copolymer and straight-run asphalt, according to the composition / straight-run asphalt (weight ratio) = The ratio of 2 to 20/98 to 80 is included.

Further, the asphalt composition of the present invention (hereinafter referred to as "asphalt composition (2)") is a block copolymer composition, straight-run asphalt, aromatic hydrocarbon resin, heavy oil, and straight-run asphalt. 100 parts by weight, based on 1 to 40 parts by weight of the composition, 0 to 40 parts by weight of the aromatic hydrocarbon resin, and 0 to 40 parts by weight of the heavy oil, and the total of the aromatic hydrocarbon resin and the heavy oil is 1 to 60 parts by weight. The ratio of the proportion of the parts contained in the torsional strength is excellent.

The block copolymer composition for modified pitch of the present invention is excellent in solubility in pitch, for example, a block copolymer composition for such modified asphalt is blended in straight-run asphalt or the like. The bitumen composition having excellent balance of toughness, softening point and ductility of the obtained asphalt and excellent torsional strength can be used for asphalt compositions for road paving or waterproof sheets.

[Best Embodiment of the Invention]

Hereinafter, the contents of the present invention will be described in detail.

The (a) block copolymer used in the block copolymer composition for modified pitch of the present invention is a polymer block mainly composed of at least two aromatic vinyl compounds, and at least one conjugate The diene as a main polymer block forms a block copolymer, and (b) the block (co)polymer uses an aromatic vinyl compound polymer block as an essential unit, and may contain the unit and the conjugate A block (co)polymer of a polymer block in which a diene is used as a host.

Here, in order to obtain the aromatic vinyl compound used for the (a) block copolymer or the (b) block (co)polymer, styrene, t-butyl styrene, α-A may be exemplified. Styrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-amine Ethyl styrene, vinyl pyridine, etc., particularly preferably styrene or α-methyl styrene.

Further, in order to obtain the conjugated diene used in the (a) block copolymer or the (b) block (co)polymer, 1,3-butadiene and 2,3-dimethyl are exemplified. -1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3 - octadiene, 3-butyl-1,3-octadiene, chloroprene, etc., preferably 1,3-butadiene, isoprene, 1,3-pentadiene, etc. Good is 1,3-butadiene.

The (a) block copolymer of the present invention is suitable for exhibiting sufficient performance in terms of the effect of the modified asphalt in the prior art, and is excellent in torsional strength and storage stability. (a) The total bonding content of the aromatic vinyl compound in the block copolymer is from 10 to 50% by weight. If the total bond content is less than 10% by weight, the softening point and toughness may not be sufficient, and And the flow resistance at high temperatures will not be sufficient. On the other hand, when it exceeds 50% by weight, the penetration of the asphalt composition is lowered and hardened, and the elongation at low temperature is lowered. It is preferably from 20 to 45% by weight.

Further, (a) the ethylene bond content in the polymer block B mainly composed of the conjugated diene in the block copolymer is usually from 10 to 40% by weight. If the ethylene bond content is 10% by weight or less, it is difficult to obtain in the production method. On the other hand, when it is 40% by weight or more, the penetration of the asphalt composition is lowered and hardened, and the elongation at low temperature is lowered. It is preferably from 10 to 35% by weight, more preferably from 10 to 30% by weight.

Further, in the block copolymer composition for modified pitch of the present invention, (a) the peak molecular weight of the polymer block mainly composed of the aromatic vinyl compound of the block copolymer is preferably 10,000 to 25,000. More preferably 10,000 to 20,000. When the peak molecular weight is 10,000 or less, the softening point and toughness of the obtained asphalt composition may be insufficient, and the degree of reduction in flow resistance may also be unfavorable. On the other hand, as in the case of 25,000 or more, the solubility is remarkably deteriorated even under the (b) block (co)polymer, and the storage stability may be deteriorated to easily cause phase separation.

Further, the polymer block mainly composed of a conjugated diene may contain an aromatic vinyl compound. For example, the fully-bonded aromatic vinyl compound in (a) may contain 0 to 40% by weight of the bonded aromatic vinyl compound, more preferably 0 to 30% by weight. Further, the structure may be a random shape or an incremental taper block. For the random and tapered analysis method, there is a method of decomposing GPC obtained by destroying the double bonds of the butadiene unit by ozone, etc. Proceedings, Vol. 29, No. 9, page 2055) or by oxidative decomposition of osmium tetroxide (Os) with tert-butyl hydroperoxide ("Journal of Polymer Science", vol. 429, 1946). For example, the polymer block having a conjugated diene as a main component contains a bonded aromatic vinyl compound to adjust a polymer block mainly composed of an aromatic vinyl compound and a polymer block mainly composed of a conjugated diene. The chain length can improve the mixing of asphalt. When the amount of the bonded aromatic vinyl compound of the polymer block mainly composed of the conjugated diene is more than 40% by weight, the molecular weight of the polymer block mainly composed of the aromatic vinyl compound may be too small. Toughness is not enough and not suitable. It can be a tapered block with an increasing molecular weight.

The (a) block copolymer has a peak molecular weight of from 100,000 to 500,000, preferably from 100,000 to 450,000, particularly preferably from 130,000 to 400,000. If the molecular weight is less than 100,000, the softening point and toughness of the obtained asphalt composition may be insufficient, and the decrease in flow resistance may also be unfavorable. On the other hand, if it exceeds 500,000, the toughness will increase a lot, but the solubility and storage stability will deteriorate and cause phase separation, and the melt viscosity of the asphalt composition will be very high, and it may be processed and handled. It is not appropriate for sex to be difficult.

(b) An example of a block copolymer comprising a polymer block mainly composed of at least two aromatic vinyl compounds and a polymer block mainly composed of at least one conjugated diene. In other words, SBS, SB-S', BSBS, BS-B'-S', (SB) _n -X, (SBS) _n -X, (SB-S') _n -X, (B- S'-B) _n -X, (SB-S'-B') _n -X, and the like. (herein, S and S' represent a polymer block mainly composed of an aromatic vinyl compound, and B and B' represent a polymer block mainly composed of a conjugated diene, and n is an integer of 2 or more, and X is an even Mixture residue base).

If the torsional strength is excellent, and the solubility in the asphalt, the storage stability at high temperature, and the workability are good, it is preferable to have a general formula (I); (SB) _n -X [general formula ( In I), S represents a polymer block mainly composed of an aromatic vinyl group, B represents a polymer block mainly composed of a conjugated diene, and n is an integer of 3 or more, and X is a coupling agent residual group] Construction.

Further, the (a) block copolymer is used as a polymerization initiator in an inert hydrocarbon solvent, for example, by first polymerizing an aromatic vinyl compound, and then polymerizing the conjugated diene to obtain a fragrance. The group of vinyl compounds can be produced by polymerizing or reacting a coupling agent.

When a coupling agent is used, the amount used is 0.1 to 2 times the molar amount of the active site derived from the polymerization initiator, preferably 0.1 to 1 mole, more preferably 0.1. Add to a ratio of 0.7 times the mole. Further, the coupling efficiency is 30% or more, preferably 40% or more, and more preferably 50% or more.

Further, in the superposition of the conjugated diene, a desired amount of the aromatic vinyl compound may be added as needed to carry out copolymerization.

For the coupling agent of the (a) block copolymer, a trifunctional coupling agent or a tetrafunctional coupling agent is preferably used. The coupling agent may, for example, be a halogenated oxime compound such as ruthenium tetrachloride, methyltrichloromethane, ruthenium tetrabromide, trifluorodecane or tribromobenzyl decane; methyltrimethoxy decane, Triethoxy oxane or tetramethoxy decane, tetraethoxy decane, γ-glycidyl oxygen a polyalkoxide such as propyltrimethoxyoxane; an ester compound such as diethyl adipate; decyl chloride such as hexamethylenedichloride; benzoic anhydride phthalic anhydride. Further, the bifunctional coupling agent may, for example, be a dihalogenated alkane such as dibromomethane, dibromoethane, dichloromethane or dichloroethane; dichlorodecane, monomethyldichlorodecane or dimethyldiene; Halogenated ruthenium compounds such as chlorodecane, dibromodecane, monomethyldibromodecane and dimethyldibromodecane; esters of ethyl formate, ethyl acetate, butyl acetate, ethyl benzoate, phenyl benzoate, etc. a compound; a tin-based compound such as dibutyltin dichloride, bisphenol A, bisphenol AD, bisphenol F, another epoxy compound, or mercapto chloride such as propylene chloride. Examples of the coupling agent having five or more functional groups include polyepoxides such as epoxidized soybean oil and epoxidized linseed oil; diaromatic vinyl compounds such as divinylbenzene and divinylnaphthalene; hexachlorobenzene and hexachlorobenzene; A halogen compound such as chlorodioxane.

The (b) block (co)polymer of the present invention can exhibit sufficient performance as an effect of upgrading asphalt in the prior art, but has processing workability such as processability and storage stability. The modified asphaltic agent which is not suitable for practical use has many improvements in solubility to asphalt and has the effect of complementing the above disadvantages, and is suitably used as a compatibilizing agent.

(b) The fully-bonded aromatic vinyl compound in the block (co)polymer is preferably more than 10% by weight to 100% by weight, more preferably more than 10% by weight and less than 100% by weight. If the content is more than 10% by weight, it is surprising that in the asphalt composition, the solubility between the pitch and the (a) block copolymer can be further improved. Here, as in the case where the (b) block (co)polymer has a fully bonded aromatic vinyl content of 100% by weight, it is a polymer block B (polymerization with a conjugated diene as a main component). Block In this case, even in this case, the solubility between the pitch and the (a) block copolymer can be exhibited.

Further, (b) the content of the ethylene bond of the polymer block mainly composed of the conjugated diene in the block (co)polymer is preferably from 10 to 50% by weight. When the content is less than 10% by weight, the compatibility effect is deteriorated, and in the method for producing the (co)polymer, it is difficult to obtain it because of the nature of the reaction. On the other hand, when the content is more than 50% by weight, the low-temperature characteristics or storage stability of the asphalt composition are inferior. More preferably, it is 12 to 40% by weight.

Further, (b) the polymer block of the block (co)polymer having an aromatic vinyl compound as a main component has a peak molecular weight of 5,000 to 50,000, preferably 5,000 to 30,000, and is polymerized with an aromatic vinyl compound as a main component. The total molecular weight of the block of the material is preferably 5,000 to 60,000. When the peak molecular weight of the polymer block mainly composed of the aromatic vinyl compound is more than 50,000, and/or the total molecular weight of the polymer block mainly composed of the aromatic vinyl compound exceeds 60,000, it is in the asphalt. The dissolution time is prolonged and does not show an improvement in storage stability. On the other hand, when the peak molecular weight of the polymer block mainly composed of the aromatic vinyl compound exceeds 5,000, and/or the total molecular weight of the polymer having the aromatic vinyl compound as a main component exceeds 5,000, the dissolution time is shortened. The viscosity is lowered and the workability is improved, but the softening point and toughness of the asphalt composition may not be sufficient.

Further, the peak molecular weight of the entire (b) block (co)polymer is preferably 5,000 to 80,000. If the molecular weight is less than 5,000, it is dissolved The time is shortened and the viscosity is lowered to obtain a workability effect, but the softening point of the asphalt composition is not sufficient. On the other hand, if the molecular weight exceeds 80,000, the improvement effect is insufficient, and in particular, the dissolution time of the asphalt is prolonged.

Further, in the polymer block mainly composed of the conjugated diene which may be contained in the entire (b) block (co)polymer, the aromatic vinyl compound may be contained in the same manner as the (a) block copolymer. For example, the fully-bonded aromatic vinyl compound in (b) may contain 0 to 90% by weight of the bonded aromatic compound, more preferably 0 to 50% by weight. Further, the structure may be a random shape or an incremental tapered block.

(b) a block (co)polymer used in the present invention, for example, an organolithium compound or the like is used as a polymerization initiator in an inert hydrocarbon solvent, and an aromatic vinyl compound and a conjugated diene are successively polymerized, that is, Can be manufactured.

For example, first, the aromatic vinyl compound is polymerized, and then the reaction is stopped after the conjugated diene is polymerized, or the aromatic vinyl compound or the conjugated diene compound is successively inserted, and the reaction is stopped when the desired structure is obtained. . Further, in the polymerization of the conjugated diene, a desired amount of the aromatic vinyl compound may be added as needed to carry out copolymerization.

As the above inert hydrocarbon solvent, a hydrocarbon such as pentane, n-hexane, heptane, octane, methylcyclopentane, cyclohexane, benzene or xylene may be used, and among them, cyclohexane is preferred.

The organic alkali metal compound which is a polymerization initiator is preferably an organolithium compound. As the organolithium compound, an organic-lithium, an organic dilithium, or an organic polylithium compound can be used.

Such organolithium compounds are ethyllithium, n-propyllithium, isopropyllithium, n-butyllithium, t-butyllithium, isoprenyldilithium, etc., and 100 by weight of the monomer. The serving is used in an amount of 0.02 to 2 parts by weight.

Further, in this case, as the microstructure, that is, the modifier of the ethylene bond content of the conjugated diene portion may be a Lewis base, for example, an ether, an amine or the like, specifically: two Ether, tetrahydrofuran, propyl ether, butyl ether, higher ether, or ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether An ether derivative of polypropylene glycol such as polyethylene glycol, propylene glycol diethyl ether or propylene glycol ethyl propyl ether such as triethylene glycol butyl ether or ethylene glycol dibutyl ether; and the amine: A tertiary amine such as tetramethylethylenediamine, pyridine or tributylamine is used together with an inert hydrocarbon solvent.

These regulators may be used as a structural regulator of an aromatic vinyl compound/conjugated diene when the aromatic vinyl compound is copolymerized in the polymerization of a polymer block mainly composed of a conjugated diene.

The polymerization is usually carried out at 20 to 120 ° C, preferably at 30 to 100 ° C. Further, the polymerization can be carried out at a certain temperature or at an elevated temperature without removing heat.

The amount of bonding of the aromatic vinyl compound in the (a) block copolymer or (b) block (co)polymer can be adjusted by the amount of monomer supplied during polymerization in each stage, and is adjusted as needed. The ethylene bonding content of the conjugated diene can be adjusted by the variables of the components of the above microscopic modifier. Further, the structure of the aromatic vinyl compound/conjugated diene having a polymer block mainly composed of a conjugated diene may be adjusted by the above microscopic modifier. Here, aromatic B The structural adjustment of the olefinic compound/conjugated diene means the control of the bonding state with the random, tapered block structure or the like of the aromatic vinyl compound bonded in the conjugated diene.

Further, the weight average molecular weight of the block (co)polymer of (a) to (b) can be adjusted by the addition amount of a polymerization initiator, for example, a second butyl lithium.

The block copolymer composition for modified pitch of the present invention contains the above-mentioned (a) block copolymer as a main component, and contains (b) a block as a solubility improving agent for pitch. Co-polymer. The weight ratio of the component (a) to the component (b) in the composition is from 95 to 70/5 to 30. When the weight ratio of the component (a) exceeds 95, the effect on workability is insufficient. On the other hand, when the weight ratio is less than 70, the torsional strength and the physical properties of the binder are insufficient. It is preferably from 90 to 70/10 to 30.

Further, in the block copolymer composition for modified pitch of the present invention, the molecular weight of the peak of the (b) block (co)polymer measured by gel permeation chromatography (GPC) is lower than (a) 1/3 of the molecular weight of the peak of the block copolymer, preferably equivalent to less than 1/80 to 1/(n+1) [n-based aromatic vinyl in the (a) block copolymer The compound is the number of polymer blocks of the host.

On the other hand, when the molecular weight is 1/3 or more, the effect as a compatibilizing agent cannot be sufficiently obtained, and the dissolution time in the pitch is prolonged. Here, the ratio of the peaks means the ratio of the highest peak (main peak main peak) among the plurality of peaks of each block copolymer.

a block copolymer composition for upgrading asphalt, which is used as a fluidity The melt flow rate of the index (G method of JIS K 7210) is preferably from 0 to 30, more preferably from 0.01 to 15, and particularly preferably from 0.01 to 10.

When the block copolymer composition for modified asphalt of the present invention is to be produced, it is preferred to separately polymerize (a) the block copolymer by a solution polymerization method using an organolithium compound as an initiator in a hydrocarbon solvent, and (b) A method in which a block (co)polymer is mixed and each of the obtained polymer solutions is mixed and homogenized to remove a solvent. For example, after the (a) block copolymer is produced as described above, the block (b) block (co)polymer solution is further subjected to solution mixing, homogenized, and then solvent-free.

Here, the component (b) can be processed by a separate final process using a special manufacturing method, but in the manufacturing equipment generally used for (b) block (co)polymer or the like, it is substantially due to the problem of incomplete adhesion or drying. Can't make it. Further, even if it is not suitable for mass production in a special apparatus, it is obviously disadvantageous in terms of cost, and it is practically preferable to carry out solvent removal and drying after mixing and homogenizing with the component (a).

Further, the block copolymer composition of the present invention can be produced by carrying out polymerization of the (a) block copolymer simultaneously with the polymerization of the above (b) block (co)polymer. For example, as a first stage, for the production of the (a) block copolymer, an aromatic vinyl compound may be contacted with a polymerization initiator (initiator-1) to carry out a reaction, and then a conjugated diene is added, and substantially After the completion of the reaction, a polymerization initiator (initiator-2) was added, and a conjugated diene was further added, and the production of the (b) block (co)polymer was started under the production of the (a) block copolymer. Finally, the aromatic vinyl compound is reacted to simultaneously form a composition of (a) the block copolymer and (b) the block copolymer. Things. Here, for the control of the molecular structure of the polymer to be produced, the addition of the initiator of the second stage is preferably after the polymerization of the conjugated diene of the first stage is completed, but the first adjustment is also possible. Below the addition amount of the conjugated diene of the segment, it is added during the polymerization, and the addition of the conjugated diene of the second stage is omitted. Further, if the molecular structure of the polymer to be produced is controlled in a precise manner, the amount of the initiator in the first stage and the second stage, the amount of the aromatic vinyl compound in the first stage, and the conjugated diene can be used. The amount of addition and the adjustment of the amount of addition of the conjugated diene and the aromatic vinyl compound in the second stage are carried out.

Next, the pitch composition (1) of the present invention contains the block copolymer composition for modified asphalt and the composition of straight-run asphalt.

Here, the straight-run asphalt used in the asphalt composition (1) is obtained by subjecting asphalt base crude oil to atmospheric distillation, steam distillation or vacuum distillation as a residue. Since the straight-run asphalt is easy to dissolve the block copolymer composition of the present invention, the processing and handling are easy.

Straight-run asphalt, preferably having a penetration of 50 to 200. When the penetration degree is less than 50, there is a tendency to affect flexibility at a low temperature, and on the other hand, when it exceeds 200, the abrasion resistance and the flow resistance tend to be lowered.

In the case of the bitumen which can be applied to the composition for reforming of the present invention, straight-run asphalt is preferred, but blown asphalt can be used without straight-running pitch (semis pitch base oil is the same as above) The bitumen obtained by the method).

The weight ratio of the block copolymer composition to the straight-run asphalt of the modified asphalt in the asphalt composition (1) is 2 to 20/98 to 80, preferably 3 Until 18/97 to 82. If the weight ratio of the block copolymer composition for modified asphalt is less than 2, the torsional strength or the modification effect of the asphalt cannot be achieved, the softening point is insufficient, and the penetration and toughness are low. On the other hand, if it exceeds 20, although the softening point and the toughness are sufficient, the dissolution time in the pitch is remarkably prolonged, and the compatibility is also deteriorated. Moreover, the melt viscosity of the asphalt composition is remarkably increased, and as a result, processing and operation management are difficult.

Further, the block copolymer composition for modified asphalt of the present invention can be usually used in the form of pellets, crumbs or powders. It is also a good idea to specify the bulk density, the particle diameter, and the total volume of the pores as described in Japanese Laid-Open Patent Publication No. Hei 11-315187.

Next, the asphalt composition (2) is composed of a block copolymer composition for the modified asphalt described above, and a straight hydrocarbon pitch similar to the above, and further contains an aromatic hydrocarbon resin and/or a heavy oil. Things.

Here, the aromatic hydrocarbon resin means rosin and its derivatives, terpene resin or petroleum resin and its derivatives, coumarone-indene resin, and alkane. A phenol resin, an alkyd resin or the like.

In addition, heavy oil refers to vegetable oil such as rice bran oil and soybean oil; animal oil such as fish oil and whale oil; petroleum heavy hydrocarbon oil such as cylinder oil and lubricating oil, but it is preferably petroleum heavy hydrocarbon from the economical point of view. Oil, especially aromatic operating oils.

The blending ratio in the asphalt composition (2) is 100 parts by weight of the straight-run asphalt, and the block copolymer composition for the modified asphalt is 1 to 40 parts by weight, preferably 3 to 30 parts by weight, and aromatic. Family hydrocarbon resin 0 to 40 weight The heavy oil is 0 to 40 parts by weight, and the total of the aromatic hydrocarbon resin and the heavy oil is 1 to 60 parts by weight, preferably 5 to 40 parts by weight.

Here, if the blending amount of the block copolymer composition for modified asphalt is less than 1 part by weight, the asphalt modification effect cannot be achieved, the torsional strength is poor, the softening point is insufficient, and the penetration degree is insufficient. On the other hand, the blending amount is more than 40 parts by weight, and although the softening point and the toughness are sufficient, the dissolution time in the asphalt is remarkably prolonged, and the compatibility is also deteriorated. Moreover, the melt viscosity of the asphalt composition is remarkably increased, and as a result, processing and operation management are difficult.

In addition, when the total amount of the aromatic hydrocarbon resin and the heavy oil is 1 part by weight or less, the fluidity and the solubility are inferior. On the other hand, if the amount is more than 60 parts by weight, the softening point is obtained. The strength is low and becomes weak.

In the pitch composition (1) and (2) of the present invention, the block copolymer composition for the modified pitch is usually used in a straight-run pitch which is heated and melted to a temperature of 140 to 190 ° C, or The composition can be produced by putting and mixing an aromatic hydrocarbon resin and/or a heavy oil.

Further, in the pitch compositions (1) and (2) of the present invention, other styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers may be used in small amounts in combination. . Further, other thermoplastic elastomers (elastomers) or thermoplastic resins such as styrene-butadiene rubber latex, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, atactic ( Atactic) Other polymers such as polypropylene, 1,2-polybutadiene, or ethylene-propylene rubber. In this case, the block copolymer composition for modified asphalt of the present invention and other polymers may be previously prepared. After mixing in any ratio, it is granulated and/or powdered and used.

Further, in the pitch compositions (1) and (2) of the present invention, additives such as a filler such as cerium oxide, talc, and calcium carbonate, a pigment, an anti-aging agent, a crosslinking agent, and a flame retardant may be added. Moreover, if it is used as a road paving, it is also possible to add sand or the like.

[Examples]

In the following, the present invention will be more specifically described by the examples, but the invention is not limited thereto.

In addition, in the examples, parts and %, unless otherwise added, are based on weight.

Further, various evaluations in the examples were obtained as follows.

Characteristics of block copolymer (1) Peak molecular weight (PM)

For the measurement of the peak molecular weight, gel permeation chromatography (HLC-8220) manufactured by Tosoh Corporation was used, and Ultrabondage E750A manufactured by Waters Co., Ltd. was used for the column. The solvent was measured using tetrahydrofuran under the conditions of a temperature of 45 ° C, a flow rate of 1.0 ml/min, a sample concentration of 0.1%, and an injection amount of 20 μl, using standard styrene (Shell Chemical Co. Ltd. (USA)). A calibration curve was prepared and calculated from the chromatogram obtained above. Moreover, the coupling efficiency and the content were also calculated from the area ratio of each component of the chromatogram.

(2) Bonded styrene content

Using an infrared spectroscopic analyzer (Fourier transformation type infrared spectroscopic analyzer manufactured by Perkin-Elmer Co., Ltd.), styrene was calculated from the absorption intensity at a wavelength of 699 cm ^-1 by a calibration line method. content.

(3) Quantitative analysis of ethylene bond content in butadiene

Based on the analysis results obtained by measuring 450 to 1,200 cm ^-1 as the measurement range, the ethylene bond content in butadiene was calculated by the molero method.

(4) Analysis of melt flow rate (MFR(G))

In this analysis, an automatic melt indexer (Model TP-404) manufactured by Tester Industrial Co., Ltd. was used. The sample was analyzed according to the G method (200 ° C, 5 kg load) of JIS K 7210, and the above composition was measured.

Characteristics of asphalt composition (1) Dissolution time A/B

The dissolution time A, when preparing the asphalt composition, takes a small amount of content in the mixing of the asphalt and applies it to the polyester (Tetoron) sheet for visual observation, which is no longer identifiable. The time until the block copolymer solid body was taken as the dissolution time A.

In the past, the asphalt composition was determined to be dissolved from the dissolution time A. The sample to be evaluated is evaluated and its performance is judged. However, it has been found that the phase structure of the asphalt and the polymer in the microscopic field has a significant influence on the physical properties of the asphalt. Although the composition which has been dissolved at the time of the determination of the dissolution time A, such as the presence of phase separation in the microscopic field, the storage stability of the asphalt composition is inferior. In the market, it is also known that if the performance of a product as a pitch composition is sufficiently exerted and the deviation in quality is prevented, a state of a single phase must be formed in the microscopic field. Therefore, the evaluation by the dissolution time B described below was carried out.

The dissolution time B was carried out as follows. In the preparation of the same asphalt composition as described above, a small amount of the contents of the mixture is taken, and the asphalt mixture is placed on a slide glass heated on a hot plate, and then covered glass is covered. Let it expand thinly. Using a transmissive microscope (transmision microscopy), a magnification of 200 times under the observation of the mixture developed on the glass, the time from the time when the sea-island structure of the asphalt phase and the polymer phase became a single phase was dissolved. Time B.

(2) Strength

When the asphalt composition is mixed, if the asphalt phase and the polymer phase are uniformly dispersed as described above and the sea-island structure exhibits a single phase, it is more suitable for the full performance, but in some comparative examples, even after 15 Stirring over a period of time still does not result in a combination of substantially incompatible systems of a single phase. If the mixture of 8 hours or more is still unable to form a single phase composition, it cannot be used as a practical person, if it is mechanically mixed semi-mandatory. When the asphalt composition is produced, the performance of storage stability and the like is still insufficient. In the comparative example, the mixing was stopped for 8 hours of the allowable range, and the performance was evaluated. In order to consider the simplicity of the evaluation work, the mixing time was uniformly set to 8 hours including the examples, and the physical property measurement described below was also carried out after 8 hours of mixing.

The test method for the asphalt mixture to be tested in this test is based on the "Pavement Test Method Manual" (issued by the Japan Association of Road Associations in November, 2013).

(3) Softening point, penetration, ductility

The measurement was carried out in accordance with JIS K 2207.

(4) Melt viscosity

The test method of the asphalt composition tested in this test was carried out at 180 ° C using a B-type viscometer.

(5) Storage stability

The asphalt composition tested in this test was poured into a container made of aluminum can, and it was allowed to stand in an oven at 180 ° C for 72 hours in a nitrogen atmosphere, and then cooled at room temperature to form an aluminum can. Divided into upper, middle and lower parts.

The following evaluation was performed using the sample which removed the upper part and the lower part of a center part.

Determination of surface skinning condition

The surface state of the upper portion of the sample was observed, and it was judged that the skin was caused by deterioration of the polymer was ×, and the state in which no skin was not formed was ○, and the results are shown in Tables 1 and 2.

Softening point difference after storage

The softening points of the upper and lower samples were measured to evaluate the degree of separation of the polymers, and the results are shown in Tables 1 and 2.

(6) Torsional strength

Using about 65% by weight of crushed stone, about 10% by weight of coarse sand, about 5% by weight of stone powder, and the designed void material can be heated and mixed at 180 to 185 ° C in such a manner that the target void ratio can be about 20%. This addition is 5% by weight of the asphalt composition which is heated and melted to 170 ° C as a binder and mixed at 170 to 175 ° C. The preparation is applicable to the "Pavement Test Method Manual (Tentative Test Method)" (Japan Road Association) The wheel tracking test method described in the issue of the wheel tracking test method has a void ratio of about 20% of the asphalt mixture. The test mixture of the asphalt mixture was subjected to a torsion strength measuring tester (fraction test machine) at a test temperature of 60 ° C, a running radius of 10 cm, a number of revolutions of 5.5 rpm, and a load of 70 kgf. It is determined that the amount of sinking of the lost tire will reach a test time of 10 mm, and the longer it is, the better.

(7) DSR (Dynamic Shear Rheometer)

In the state where the island structure of the block copolymer composition of the pitch phase and the modified asphalt is a single phase, the measurement is performed using a dynamic shear rheometer (rheological science, manufactured by F.E.), according to a 25 mm plate, gap. 2 mm, strain 5%, G* value (complex modulus) at a frequency of 1 rad/sec at the test temperature of 60 °C. If the G* value is high, the torsional strength is good.

Example 1 Modulation of block copolymer composition (1) (a) Polymerization of block copolymer

A stainless steel polymerization vessel containing a jacket and a mixer in a volume of 100 liters was sufficiently substituted with nitrogen, and then fed with 50 kg of cyclohexane, 0.5 g of ethylene glycol diethyl ether, and 1.6 kg of styrene. The warm water was introduced into the casing to make the contents 40 °C.

Next, 5.9 g of a second butyllithium was added to start polymerization. After the completion of the polymerization of styrene, the temperature of the temperature-regulated content was 80 ° C, and 4.8 kg of 1,3-butadiene was slowly added. After the polymerization of the B block was completed, 1.6 kg of styrene was added and allowed to react for 30 minutes. After the reaction, 1 ml of methanol was added and stirred for 10 minutes, and then pipetted into a blend container.

(2) (b) Polymerization of block (co)polymer

In the same manner as in (1), a stainless steel polymerization vessel containing a casing and a stirrer in an amount of 5 liters was sufficiently substituted with nitrogen, and then fed to cyclohexane 3 kg, ethylene glycol diethyl ether 1.2 g, and benzene. 0.17kg of ethylene, open inside the casing Warm water is used to make the contents 40 °C.

Next, 2.2 g of second butyllithium was added to start polymerization. After the completion of the polymerization of styrene, the temperature of the temperature-regulated content was 80 ° C, and 0.72 kg of 1,3-butadiene was slowly added. After completion of the polymerization of the B block, 3 ml of methanol was added and stirred for 10 minutes, and then pipetted into a blending vessel.

(3) Modulation of the composition

After mixing the above-mentioned block copolymers (a) and (b), the contents were taken out from the blending container, and 50 g of 2,6-t-butylcresol (BTH) which is an oxidation preventing agent was added. This mixed polymerization solution was subjected to steam stripping, and the obtained polymer was made into a crumb shape using a crusher, and then dried by hot air at 80 ° C to obtain a block copolymer composition. .

Modulation of asphalt composition

558 g of straight-run asphalt (60/80, manufactured by Showa Shell Co., Ltd.) having a penetration degree of 70, and 42 g of the above-mentioned block copolymer composition were used, and a stirrer was used under heating at 180 ° C [Special Machine Chemical Industry Co., Ltd., TK A homomixer, 10,000 rpm] was mixed to prepare the asphalt composition. In Table 1, the evaluation results of the respective characteristics are shown.

Fig. 1 is a photomicrograph showing the asphalt composition after 6 hours. It can be seen that the block copolymer composition of the pitch phase and the modified asphalt has been subjected to single phase formation.

Examples 2 to 6

The modification shown in Table 1 was carried out in the same manner as in Example 1 except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether was changed. A block copolymer composition for pitch, a pitch composition was prepared, and its properties were evaluated.

In Table 1, the evaluation results of the respective characteristics are shown.

Example 7

(a) The block copolymer is produced as follows. That is, in the same stainless steel polymerization vessel as in Example 1, 50 kg of cyclohexane, 2.0 g of ethylene glycol diethyl ether, and 0.96 kg of styrene were fed, and the warm water was introduced into the casing to make the contents 40. °C.

Next, 5.1 g of second butyllithium was added to start polymerization. After the completion of the polymerization of styrene, the temperature of the temperature-regulated content was 80 ° C, and 5.44 kg of 1,3-butadiene and 0.64 kg of styrene were slowly added. After the polymerization of the B block was completed, 0.96 kg of styrene was added and allowed to react for 30 minutes. After the reaction, 5 ml of methanol was added and stirred for 10 minutes, and then pipetted into a mixing vessel.

(b) block (co)polymer, except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, ethylene glycol diethyl ether is changed, and the rest is as in the examples. (1) Polymerization was carried out in the same manner to obtain a block copolymer shown in Table 1, and the same procedure as in Example 1 was carried out to obtain a block copolymer composition for modified pitch, a pitch composition, and the properties thereof were evaluated. In Table 1, the evaluation results of the respective characteristics are shown.

Example 8

(a) The block copolymer is produced as follows. That is, in the same stainless steel polymerization vessel as in Example 1, 50 kg of cyclohexane, 8.5 g of ethylene glycol diethyl ether, and 1.08 kg of styrene were fed, and warm water was introduced into the casing to make the contents 40. °C.

Next, 4.8 g of second butyllithium was added to start polymerization. After the completion of the polymerization of styrene, 5.84 kg of 1,3-butadiene was added and subjected to thermal decomposition polymerization. The temperature at which the polymerization of the B block was completed reached 80 °C. Thereafter, 1.08 kg of styrene was added and allowed to react for 30 minutes. After the reaction, 5 ml of methanol was added and stirred for 10 minutes, and then pipetted into a mixing vessel.

(b) Block (co)polymer, which was polymerized in the same manner as in Example 1 except that 1,3-butadiene was not added and the feed amount of styrene and second butyllithium was changed. The block copolymer shown in Table 1 was obtained, and the same procedure as in Example 1 was carried out to obtain a block copolymer composition for modified pitch, a pitch composition, and the properties thereof were evaluated. In Table 1, the evaluation results of the respective characteristics are shown.

Example 9

(b) Block (co)polymer, in the same stainless steel polymerization vessel as in Example 1, fed with 10 kg of cyclohexane, 0.7 g of ethylene glycol diethyl ether, and 2.21 kg of styrene. The warm water is used to make the contents 40 °C.

Next, 28.2 g of second butyllithium was added to start polymerization. After the styrene polymerization was completed, the temperature of the temperature-regulated content was 80 ° C, and 0.51 kg of 1,3-butadiene and 0.68 kg of styrene were slowly added. Addition of the B block after the polymerization is completed 20 ml of methanol was added and stirred for 10 minutes, and then pipetted into a blending vessel. Next, in addition to the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether, the (a) block was obtained in the same manner as in Example 1. After the above-mentioned component (b) was mixed, the copolymer was mixed in the same manner as in Example 1 to obtain a block copolymer composition for modified pitch and a pitch composition, and the properties thereof were evaluated. In Table 1, the evaluation results of the respective characteristics are shown.

Example 10

(a) The block copolymer is a block copolymer shown in Table 1 in the same manner as in Example 2 except that the peak molecular weight of the polymer mainly composed of two aromatic vinyl compounds is a variable. That is, in the same stainless steel polymerization vessel as in Example 1, 50 kg of cyclohexane, 10.0 g of ethylene glycol diethyl ether, and 1.06 kg of styrene were fed, and warm water was introduced into the casing to make the contents into contents. 40 ° C.

Next, 5.7 g of second butyllithium was added to start polymerization. After the completion of the polymerization of styrene, 5.36 kg of 1,3-butadiene was slowly added. After the polymerization of the B block was completed, 30 ml of the polymerization solution was taken out. The peak molecular weight by gel permeation chromatography was 122,000. Thereafter, 1.58 kg of styrene was added to allow the reaction to proceed for 30 minutes, and after the reaction, 5 ml of methanol was added, and the mixture was stirred for 10 minutes, and then transferred to a mixing vessel.

(b) Block (co)polymer was polymerized in the same manner as in Example 2, and the block copolymer shown in Table 1 was obtained, and the same operation as in Example 1 was carried out to obtain a modified asphalt. The segment copolymer composition, the asphalt composition, and the properties thereof were evaluated. In Table 1, the evaluation results of the respective characteristics are shown.

Example 11

(a) The block copolymer was fed to a stainless steel polymerization vessel of the same manner as in Example 1 and fed with 50 kg of cyclohexane, 0.5 g of ethylene glycol diethyl ether, and 1.6 kg of styrene, and heated water was passed through the casing. In order to make the content 40 ° C.

Next, 7.9 g of second butyllithium was added to start polymerization. After the completion of the polymerization of the styrene, the temperature of the temperature-regulated content was 80 ° C, and 6.4 kg of 1,3-butadiene was slowly added to allow the reaction to proceed for 30 minutes. Next, 9.1 g of ν-glycidoxypropyltrimethoxydecane was added and allowed to react for 15 minutes. After the reaction, 1 ml of methanol was added and stirred for 10 minutes, and then pipetted into a mixing vessel.

(b) block (co)polymer, except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, ethylene glycol diethyl ether is changed, and the rest is as in the examples. In the same manner, the block copolymer composition and the asphalt composition for modified asphalt shown in Table 2 were obtained, and the properties thereof were evaluated. In Table 2, the evaluation results of the respective characteristics are shown.

Examples 12 to 17

Except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether was changed, the same procedure as in Example 11 was carried out ((b) of Example 17 The segment (co)polymer was not added with 1,3-butadiene, and the block copolymer composition for modified asphalt shown in Table 4 was prepared to prepare a pitch composition, and the properties were evaluated. In Table 2, the evaluation results of the respective characteristics are shown.

Example 18

(a) The block copolymer was fed to a stainless steel polymerization vessel of the same manner as in Example 1 and fed with 50 kg of cyclohexane, 8.1 g of ethylene glycol diethyl ether, and 2.4 kg of styrene, and heated water was passed through the casing. In order to make the content 40 ° C.

Next, 12 g of second butyllithium was added to start polymerization. After completion of the polymerization of styrene, the temperature of the temperature-regulated content was 80 ° C, and 5.6 kg of 1,3-butadiene was slowly added to allow the reaction to proceed for 30 minutes. Next, 30 g of Nippon Polybutadiene E-1800-6.5, which was previously dissolved in 100 ml of toluene, was added and reacted for 15 minutes. After the reaction, 1 ml of methanol was added and stirred for 10 minutes, and then pipetted into a mixing vessel.

(b) block (co)polymer, except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, ethylene glycol diethyl ether is changed, and the rest is as in the examples. In the same manner, the block copolymer composition and the asphalt composition for modified asphalt shown in Table 4 were obtained, and the properties thereof were evaluated. In Table 2, the evaluation results of the respective characteristics are shown.

Comparative example 1

One is that no (b) block (co)polymer is added, and (a) the block copolymer is modified to change styrene, 1,3-butadiene, second butyl lithium, ethylene glycol diethyl Except for the feed amount of the ether, the (a) block copolymer was obtained in the same manner as in Example 1 to prepare a pitch composition, and the properties thereof were evaluated. In Table 3, the evaluation results of the respective characteristics are shown.

Fig. 2 is a photomicrograph showing the asphalt composition after 8 hours. It can be seen from the figure that the asphalt phase (island phase) and the block copolymer composition phase (marine phase) for the modified asphalt are separated into islands.

Comparative Examples 2 to 5

The modification shown in Table 3 was carried out in the same manner as in Example 1 except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether was changed. A block copolymer composition for pitch, a pitch composition was prepared, and its properties were evaluated. In Table 3, the evaluation results of the respective characteristics are shown.

Comparative Examples 6 to 10

The modification shown in Table 4 was carried out in the same manner as in Example 14 except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether was changed. A block copolymer composition for pitch, a pitch composition was prepared, and its properties were evaluated. In Table 4, the evaluation results of the respective characteristics are shown.

As can be seen from Tables 1 and 2, the asphalt composition of the present invention has a short dissolution time for pitch and a low viscosity of melt viscosity, good storage stability, and good toughness, softening point and ductility, and G* The fact that the value is high and the torsional strength is excellent.

On the other hand, as is clear from Table 3, Comparative Example 1 which does not contain the asphalt composition of the (b) block (co)polymer of the present invention has a long dissolution time and a high melt viscosity, and has a high G* value but is resistant. The torsional strength is inferior and the storage stability is poor. Comparative Example 2 is that the ratio of (a) block copolymer / (b) block (co)polymer is outside the range of the present invention as 65/35, and the G* value is low, and the torsional strength is poor. The softening point is lower and the toughness is lower. In Comparative Example 3, the peak molecular weight of the (a) block copolymer was more than the range of the present invention, the dissolution time was long, the melt viscosity was high, the G* value was high, but the torsional strength was inferior, and the storage stability was inferior. Comparative Example 4 is that the content of the fully bonded aromatic vinyl compound in the (a) block copolymer is outside the scope of the present invention, and the G* value is low, the torsional strength is low, the softening point is low, and the toughness is high. Lower. In Comparative Example 5, the content of the fully-bonded aromatic vinyl compound in the (a) block copolymer is more than the range of the present invention, and the G* value is low, the torsional strength is low, the softening point is low, and the penetration degree is higher. Low and low toughness.

As is clear from Table 4, Comparative Example 6 is a pitch composition which does not contain the (b) block (co)polymer of the present invention, has a long dissolution time, has a high melt viscosity, and has a high G* value but a poor torsional strength. Storage stability is poor. Comparative Example 7 is that the ratio of (a) block copolymer / (b) block (co)polymer is outside the range of the present invention as 65/35, and the G* value is low, and the torsional strength is poor. , lower softening point, lower toughness, comparative example 8 series (a) peak of block copolymer The value molecular weight is more than the range of the present invention, and the dissolution time is long, the melt viscosity is high, and the G* value is high, but the torsional strength is inferior and the storage stability is inferior. In Comparative Example 9, the content of the fully bonded aromatic vinyl compound in the (a) block copolymer is less than the range of the present invention, and the G* value is high, the torsional strength is poor, the softening point is low, and the toughness is high. Lower. In Comparative Example 10, the peak molecular weight in the (b) block (co)polymer is 1/3 or more of the peak molecular weight of the (a) block copolymer, which is longer than the range of the present invention, and the dissolution time is long and melted. The viscosity is high, the G* value is high, but the torsional strength is inferior and the storage stability is inferior.

Examples 19 to 24 (Examples of using aromatic hydrocarbon resin and heavy oil in combination)

Table 5 obtained in the same manner as in Example 1 or Example 11 except that the feed amount of styrene, 1,3-butadiene, t-butyllithium, and ethylene glycol diethyl ether was changed. 60 g of the block copolymer composition for modified pitch shown in the above, and 18 g of an aromatic hydrocarbon resin (manufactured by Anwar Chemical Co., Ltd.), and aromatic process oil (process oil) Co., Ltd.: AE20H) 60g, straight-run asphalt with a penetration of 70 [60/80] made by Showa Shell Co., Ltd., 462g, and a mixer (Special Machine Chemical Industry Co., Ltd., TK homomixer, used under heating at 190 °C) 10,000 rpm] was mixed to prepare a pitch composition. In Table 5, the evaluation results of the respective characteristics are shown.

As is apparent from Table 5, Examples 19 to 24 are used together with the aromatic hydrocarbon resin and the heavy oil pitch composition in the range of the present invention, and the dissolution time to the asphalt is short, the melt viscosity is low, and G* The fact that the value is high, the torsional strength is excellent, the storage stability is good, and the good toughness, softening point, and ductility are exhibited.

[Industry use area]

The block copolymer composition for modified asphalt obtained by the (a) block copolymer of the present invention and (b) the block (co)polymer is excellent in solubility and excellent in torsional strength. It is very suitable for the manufacture of road paving, especially for drainage/low-sound paving or waterproof sheet, sound-blocking sheet, water-stopping material, roofing material, sealing material, covering material, soundproofing material sheet, steel pipe coating Cover the asphalt composition.

Fig. 1 is a photomicrograph showing the case where the asphalt phase composition of the asphalt composition of Example 1 and the block copolymer composition for modified pitch are mutually dissolved and the sea-island structure is monophased (1). Scale = 1 μm).

Fig. 2 is a photomicrograph (1 scale = 1 μm) showing a case where the pitch phase of the asphalt composition of Comparative Example 1 and the block copolymer composition phase of the modified asphalt are not dissolved in each other and separated into an island structure.

Claims (9)

A block copolymer composition for modified asphalt characterized by (a) a polymer block mainly composed of at least two aromatic vinyl compounds, and at least one conjugated diene as a main component The polymer block is formed into a block copolymer, and the content of the fully bonded aromatic vinyl compound in the block copolymer is 20 to 45% by weight, and the ethylene bond in the polymer block mainly composed of the conjugated diene a knot copolymer having a peak content of 100 to 10,000 to 500,000 by a gel permeation chromatography (GPC), and a (b) The aromatic vinyl compound polymer block is an essential unit, and may contain a block (co)polymer of a polymer block having such a unit and one or more conjugated dienes as a main component, and the block (co)polymerizes The content of the fully-bonded aromatic vinyl compound of the material is more than 10% by weight and is 100% by weight or less, and the content of the ethylene bond in the polymer block as the main body of the conjugated diene is 10 to 50% by weight, and by coagulation Standard polystyrene-converted peak molecular weight as determined by gel permeation chromatography (GPC) a block (co)polymer of less than 1/3 of the peak molecular weight of the (a) block copolymer, in a ratio of (a) / (b) (weight ratio) = 95 to 70/5 to 30 contain. The block copolymer composition for modified asphalt according to claim 1, wherein (a) the block copolymer may be of the general formula (I); (SB) _n -X [in general formula (I), S represents a polymer block mainly composed of an aromatic vinyl compound, B represents a polymer block mainly composed of a conjugated diene, and n is an integer of 3 or more, and X is a coupling agent residual group]. The block copolymer composition for modified asphalt according to claim 1 or 2, wherein (a) the molecular weight of the polymer block mainly composed of the aromatic vinyl compound of the block copolymer is 10,000 The block copolymer of 25,000 parts, and (b) the polymer block mainly composed of the aromatic vinyl compound of the block (co)polymer has a peak molecular weight of 5,000 to 50,000. The block copolymer composition for modified asphalt according to claim 1 or 2, wherein (a) the molecular weight of the polymer block mainly composed of the aromatic vinyl compound of the block copolymer is 10,000 Block copolymer to 20,000, and the overall peak molecular weight is from 130,000 to 400,000. A block copolymer composition for modified asphalt according to the first or second aspect of the patent application, wherein (b) a peak of a polymer block mainly composed of an aromatic vinyl compound of a block (co)polymer The molecular weight is from 5,000 to 30,000, and the total molecular weight of the polymer block is from 5,000 to 60,000, and the total peak molecular weight of the whole is from 5,000 to 80,000. The block copolymer composition for modified asphalt according to claim 1 or 2, wherein the peak molecular weight of the (b) block (co)polymer is equivalent to lower than that of the (a) block copolymer. 1/80 to 1/(n+1) of the peak molecular weight [n is (a) the number of polymer blocks mainly composed of an aromatic vinyl compound in the block copolymer]. A method for producing a block copolymer composition for modified asphalt according to any one of claims 1 to 6, which is characterized in that: The (a) block copolymer, and (b) the block (co)polymer are separately polymerized by an aqueous solution of an organolithium compound as an initiator in an inert hydrocarbon solvent, and the obtained polymer solution is mixed and After homogenization, it is desolvated to produce. An asphalt composition characterized by the composition of any one of claims 1 to 6, and straight-run asphalt, according to the composition/rectified asphalt (weight ratio) = 2 to 20/ The ratio of 98 to 80 is contained. An asphalt composition characterized by comprising the composition of any one of the first to sixth aspects of the patent, and a straight-run asphalt, an aromatic hydrocarbon resin, and a heavy oil, and 100 parts by weight of straight-run asphalt 1 to 40 parts by weight of the composition, 0 to 40 parts by weight of the aromatic hydrocarbon resin, and 0 to 40 parts by weight of the heavy oil, and the total weight of the aromatic hydrocarbon resin and the heavy oil is 1 to 60 parts by weight. The proportion of the way is included.