JPH0925416A - Asphalt modifier and asphalt composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an asphalt modifier capable of providing an asphalt composition, excellent in solubility, processability and storage stability for asphalt and further binder characteristics such as penetration, toughness and tenacity and improved in characteristics such as operability. SOLUTION: This asphalt modifier comprises 100 pts.wt. vinyl aromatic hydrocarbon-conjugated diene block copolymer, 10-300 pts.wt. tackifying resin and 10-300 pts.wt. process oil with 0-40wt.% aromatic component content. Furthermore, the asphalt composition is obtained by mixing asphalt with the asphalt modifier.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an asphalt modifier and an asphalt composition containing the same, and more specifically, it has excellent solubility in asphalt and improved properties such as processability and storage stability. Moreover, it is possible to provide an asphalt composition having excellent binder properties such as penetration, softening point, toughness, tenacity, and 60 ° C. viscosity, and further, a mixture of porosity, dynamic stability, aggregate scattering resistance and the like. The present invention relates to an asphalt modifier capable of giving an asphalt mixture having excellent properties and workability. The invention further relates to asphalt compositions containing such modifiers.

[0002]

2. Description of the Related Art Conventionally, asphalt has been liquefied at high temperature to increase workability, and solidified at normal temperature or low temperature to increase binding strength and to exhibit strength. It is used in a wide range of applications such as roofing materials, sealing materials, and covering materials.
However, the basic characteristics of these asphalts, on the other hand, were also the drawbacks of asphalt.

That is, when asphalt is used as a road pavement material, since the asphalt has a large temperature dependency, it is likely to be modified by plastic flow under high temperature in summer, and cracks due to hardening during winter. Also, there was a problem that the wear was severe due to tire chains. Further, since asphalt generally has a weak adhesive force at the joint surface with the aggregate, it has a drawback that the aggregate easily peels off from the asphalt.

To address these problems, ethylene
Vinyl acetate copolymer, polyethylene, polypropylene,
Thermoplastic resin such as ethylene / ethyl acrylate copolymer, styrene / butadiene random copolymer rubber,
It has been dealt with by a technical means of improving the asphalt by blending rubbers such as chloroprene rubber alone or in combination. However, the effect of modification by these means was not sufficient. For example, in the modification with a thermoplastic resin, the elasticity of asphalt is increased, but the compatibility with asphalt is poor, and there are drawbacks such as inferior properties such as elongation ability and adhesion, and in the modification with rubber, The softening point and the fluidity resistance were not sufficiently improved, and there were still problems such as poor compatibility with asphalt.

In order to solve such problems, in recent years,
Consideration has been given to the use of block copolymers such as styrene / butadiene block copolymers, and considerable results have been recognized. However, the technique using these block copolymers has caused new problems. That is, since the block copolymer has poor solubility in asphalt, for example, in order to completely dissolve the styrene-butadiene block copolymer in the asphalt, it is necessary to maintain a heating and stirring state for at least 5 hours or more. There is a problem that it takes a lot of time and labor for melting, and it is necessary to prepare a premix facility for mixing the two in advance.

Therefore, the present inventors reduce the characteristics such as the softening point and the dynamic stability by previously kneading the block copolymer, the aromatic hydrocarbon resin and the aromatic oil. A technique for significantly improving the solubility in asphalt (Japanese Patent Laid-Open No. 5-29527).
No. 3). However, with this technique, there is room for further improvement in the processability of the asphalt modifier, the storage stability, and the workability of the asphalt mixture using the asphalt modifier.

[0007]

The object of the present invention is to have excellent solubility in asphalt, improved properties such as processability and storage stability, and binder properties such as penetration, toughness and tenacity. It is an object of the present invention to provide an excellent asphalt composition, an asphalt modifier capable of providing an asphalt mixture having improved properties such as mixture properties and workability, and an asphalt composition containing the asphalt modifier.

The inventors of the present invention have conducted extensive studies to overcome the above-mentioned problems of the prior art, and as a result, have found that a styrene / butadiene block copolymer, a tackifying resin and a process oil having a limited aromatic component content. By using an asphalt modifier pre-kneaded with a specific amount, solubility and penetration, toughness, without degrading the binder properties such as tenacity, asphalt composition improved processability and storage stability, It was found that an asphalt mixture which was obtained and was excellent in workability was obtained, and the present invention was completed.

[0009]

Thus, according to the present invention, 100 parts by weight of a vinyl aromatic hydrocarbon / conjugated diene block copolymer, 10 to 300 parts by weight of a tackifying resin,
And a modifier for asphalt, which comprises 10 to 300 parts by weight of a process oil having an aromatic content of 0 to 40% by weight. Further, according to the present invention, there is provided an asphalt composition containing asphalt and the above-mentioned asphalt modifier.

The present invention will be described in detail below. Block Copolymer The vinyl aromatic hydrocarbon / conjugated diene block copolymer used in the present invention is not particularly limited as long as it is generally used as an asphalt additive, and for example, partially or completely. It may be hydrogenated or modified with a modifier such as maleic anhydride.

Usually, at least one polymer block (A) mainly composed of vinyl aromatic hydrocarbon, preferably 2
A block copolymer having at least one polymer block (B) mainly containing a conjugated diene compound can be used.

The polymer block (A) mainly composed of vinyl aromatic hydrocarbon means that the vinyl aromatic hydrocarbon exceeds 50% by weight, preferably 60 to 100% by weight, more preferably 70 to 100% by weight, and further. Preferably 80-100
It is a polymer block contained in a weight percentage, and is a homopolymer of vinyl aromatic hydrocarbon or a polymer block composed of vinyl aromatic hydrocarbon and conjugated diene. The distribution of the conjugated diene in the polymer block (A) is random,
It may be tapered, partially block-shaped, or a combination thereof. The polymer block (B) containing a conjugated diene compound as a main component means 50% by weight of a conjugated diene.
A polymer block containing an excess amount, preferably 60 to 100% by weight, more preferably 70 to 100% by weight, further preferably 80 to 100% by weight, which is a homopolymer of conjugated diene or a conjugated diene and vinyl aroma. It is a polymer block composed of a group hydrocarbon. The distribution of vinyl aromatic hydrocarbons in the polymer block (B) is random,
It may be tapered, partially block-shaped, or a combination thereof.

The block copolymer may have either a linear structure or a branched structure, and preferably has a structure represented by the following general formulas (a) to (f). (A) (AB) m (b) (AB) nA (c) (BA) mB (d) ((AB) n) p-X (e) (( B-A) m) p-X (f) ((A-B) n-A) p-X (to) ((B-A) n-B) p-X

In these general formulas, A is a polymer block (A) mainly containing a vinyl aromatic hydrocarbon, and B is a polymer block (B) mainly containing a conjugated diene. X is a residue of a polyfunctional coupling agent or a residue of a polyfunctional initiator. m is an integer of 1 or more,
It is preferably an integer of 2 or more, more preferably an integer of 2-6. n is an integer of 1 or more, preferably an integer of 1 to 6, and more preferably 1. p is an integer of 2-6.

The composition ratio of the vinyl aromatic hydrocarbon and the conjugated diene in the block copolymer is not particularly limited, but in order to highly balance the binder properties such as toughness and tenacity and the low temperature characteristics, the weight ratio is high. At 5: 95-9
The range is 5: 5, preferably 10:90 to 50:50, and more preferably 15:85 to 45:55.

The amount of vinyl bonds in the conjugated diene portion of the block copolymer is not particularly limited, but usually 90% or less,
It is preferably in the range of 1 to 60%, more preferably 5 to 30%. If the vinyl bond amount is excessively large, the penetration of the asphalt composition may be lowered.

The molecular weight of the block copolymer used in the present invention is not particularly limited, but the solubility in asphalt and the binder properties such as penetration, toughness, tenacity and low temperature properties are highly balanced. In order to do so, in terms of polystyrene-converted weight average molecular weight measured by GPC,
10,000 to 1,000,000, preferably 20,
000 to 800,000, more preferably 50,000
~ 500,000.

The block copolymer used in the present invention can be prepared by a known method, for example, in JP-B-36-19286, JP-B-43-17979, and JP-B-45-31.
In accordance with the method described in Japanese Patent Publication No. 951 and Japanese Patent Publication No. S46-32415, etc., it is produced by polymerizing a vinyl aromatic hydrocarbon and a conjugated diene using an organic lithium compound as an initiator in a hydrocarbon solvent. You can At the time of polymerization, a polar compound can be used for the purpose of adjusting the reactivity ratio of vinyl aromatic hydrocarbon and conjugated diene, changing the microstructure of the polymerized conjugated diene portion, adjusting the polymerization rate, and the like.

Examples of vinyl aromatic hydrocarbons include:
Styrene, α-methylstyrene, o-methylstyrene,
p-methylstyrene, pt-butylstyrene, 2,4
-Dimethyl styrene, vinyl naphthalene, vinyl anthracene and the like. Among these, styrene is particularly preferred. The vinyl aromatic hydrocarbons may be used alone or in combination of two or more.

As the conjugated diene, for example, 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3
-Dimethyl-1,3-butadiene, 1,3-hexadiene and the like. Among these, 1,3-butadiene and isoprene are preferable, and 1,3-butadiene is particularly preferable. The conjugated dienes can be used alone or in combination of two or more.

The hydrocarbon solvent used as a polymerization solvent in the production of the block copolymer is, for example, butane,
Aliphatic hydrocarbons such as pentane, hexane, isopentane, heptane, octane, isooctane; cycloaliphatic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane; aromatics such as benzene, ethylbenzene, xylene Group hydrocarbons; and the like. These are used alone or in admixture of two or more. The amount of the hydrocarbon solvent used is usually 1% by weight to the above monomer concentration.
It is used so as to be 50% by weight.

Examples of polar compounds include ethers such as tetrahydrofuran, diethyl ether, anisole, dimethoxybenzene, and ethylene glycol dimethyl ether; amines such as triethylamine, tetramethylenediamine, N-dimethylaniline, and pyridine; thioethers. Phosphines, phosphoamides,
Examples thereof include alkylbenzene sulfonic acids and alkoxides such as potassium and sodium, which are appropriately selected according to the required performance. The amount of the polar compound used is appropriately determined according to the kind of the compound and the required characteristics, but is usually 0.001 to 1 mol amount, preferably 0.01 to 0.5 mol amount per 1 mol of the organolithium compound. Is the range.

Examples of the organolithium compound used as the initiator include polyfunctional initiators such as organomonolithium compounds and organodilithium compounds. Specific examples include, for example, n-butyllithium, sec-butyllithium and tert. -Butyllithium, n-hexyllithium, iso-hexyllithium, phenyllithium, naphthyllithium, hexamethylenedilithium, butadienyldilithium, isoprenyldilithium and the like can be mentioned. Generally, organic monolithium compounds are used,
These are used alone or in combination of two or more. The amount used is the molecular weight of the target polymer,
It is appropriately selected depending on the type of the organolithium compound,
For example, taking n-butyllithium as an example, the amount is usually 0.001 to 1 part by weight, preferably 0.01 to 1 part by weight, per 100 parts by weight of the total amount of the monomers.

The polymerization reaction may be an isothermal reaction or an adiabatic reaction, and is usually 0 to 150 ° C., preferably 20 to 12
It is performed in a temperature range of 0 ° C.

As the block copolymer, a block copolymer produced by adding a polyfunctional coupling agent after the above polymerization reaction can also be used. Examples of the polyfunctional coupling agent include tin tetrachloride, tin dichloride, tin tetrabromide, silicon tetrachloride, silicon tetrabromide, silicon tetraiodide, germanium tetrachloride, lead dichloride, methyltrichlorosilane and dimethyl. Metal compounds such as dichlorosilane, butyltrichlorosilane, dibutyldichlorotin, bistrichlorosilylethane, bistrichlorostannylethane, tetramethoxysilicon, tetramethoxytin, tetraethoxysilicon, tetraethoxytin, tetrabutoxysilicon and tetrabutoxytin; Unsaturated nitriles such as ethylacrylonitrile; dihalogenated hydrocarbons such as dibromobenzene, dichlorobenzene, dibromoethylene; dimethyl adipate, diethyl adipate, ethyl benzoate, dimethyl terephthalate, diethyl terephthalate , Dimethyl phthalate, carboxylic acid esters such as dimethyl isophthalate; terephthalic acid dichloride, dichloride phthalic acid, isophthalic acid dichloride, carboxylic acid halides such as adipic acid dichloride; four such carbontetrachloride and the like.

These polyfunctional coupling agents are used alone or in admixture of two or more, and the amount used is usually 0.01 to 2 per organolithium compound.
The range is equivalent, preferably 0.05 to 1.0 equivalent, and more preferably 0.1 to 0.5 equivalent. The coupling reaction is usually performed at 0 to 150 ° C. for 0.1 to 20 hours.

As the block copolymer, those partially or completely hydrogenated can be used. Hydrogenation is carried out by (1) a heterogeneous catalyst in which a metal such as Ni, Rt, Pd or Ru is supported on a carrier such as carbon, silica, alumina, diatomaceous earth, or (2) Ni, Co, Fe, C.
Organic acid salt such as r or acetylacetone salt and organic Al
Ziegler type catalyst or Ru using a reducing agent such as
It is carried out using a homogeneous catalyst such as an organic complex catalyst such as an organometallic compound such as Rh. Generally, for example, Japanese Examined Patent Publication Nos. 42-8704, 43-6636, and Japanese Patent Laid-Open No. 52-
41690, 59-133203, and 60-22.
As described in No. 0147, a method of hydrogenating in the presence of a hydrogenation catalyst in an inert solvent is adopted.

As the block copolymer, it is possible to use a block copolymer produced by adding a modifier after the polymerization reaction. As the modifier, for example, Japanese Patent Publication No. 62-6
Unsaturated carboxylic acids such as maleic anhydride disclosed in Japanese Patent No. 1615, and imino compounds, cyanamide compounds, aziridinyl compounds, amide compounds and the like disclosed in Japanese Patent Publication No. 4-387770.

Asphalt modifier In the present invention, a process oil containing no or a small amount of aromatic components is used. That is, the aromatic component content is 0 to 40% by weight, preferably 0 to 20% by weight, more preferably 0 to 10% by weight. When the content of the aromatic component exceeds 40% by weight, problems such as adhesion to the pelletizer blade during processing of the modifier into pellets and mutual adhesion of modifier pellets during storage are not preferable. The ratios of the remaining naphthene component and paraffin component other than the aromatic component are not particularly limited and may be individual, but each is usually 1 by weight.
0-90: 90-10, preferably 20-50: 80-
50.

The amount of the process oil used is 10 to 300 parts by weight, preferably 20 to 200 parts by weight, and more preferably 50 to 150 parts by weight, based on 100 parts by weight of the block copolymer. If the amount of the process oil used is too small, the properties such as solubility in asphalt and the elongation will be poor, and if it is too large, the properties such as the softening point and the toughness will be poor.

The tackifying resin used in the present invention is not particularly limited as long as it is a resin generally used in the industry. For example, coumarone indene resin, phenol resin, pt-butylphenol acetylene resin. , Phenol-formaldehyde resin, terpene-phenol resin, polyterpene resin, xylene-formaldehyde resin, C5-based petroleum resin, C9-based petroleum resin, dicyclopentadiene-based resin, polybutene, rosin, and hydrogenated products thereof or maleic anhydride. And the like. Among these, C5-based petroleum resin, C9-based petroleum resin, dicyclopentadiene-based resin and the like are preferable, and C9-based petroleum resin is particularly preferable.

These tackifying resins may be used alone or in admixture of two or more. The amount of tackifying resin used is usually 10 to 300 parts by weight, preferably 20 to 100 parts by weight, per 100 parts by weight of the block copolymer.
200 parts by weight, more preferably 50 to 150 parts by weight. If the amount of tackifying resin used is too small, the properties such as the softening point, the viscosity at 60 ° C., and the dynamic stability will be poor, and conversely
If it is excessively large, the properties such as elongation and toughness are deteriorated, which is not preferable.

If desired, a blocking resistance agent can be added to the asphalt modifier of the present invention. The anti-blocking agent is not particularly limited as long as it is one generally used in industry, and for example, JP-A-56-1 is used.
No. 36347, Japanese Patent Laid-Open No. 61-101503,
JP-A-5-98051 and JP-A-6-228.
Organic and inorganic compounds described in Japanese Patent No. 521, etc. are used.

Examples of organic anti-blocking agents include higher fatty acid monoamides such as stearic acid amide, oleic acid amide, lauric acid amide, barmitic acid amide, erucic acid amide, and behenic acid amide; methylenebisstearic acid amide, ethylenebis Higher fatty acid bisamides such as stearic acid amide, ethylene bis oleic acid amide and ethylene bis lauric acid amide; N-stearyl oleic acid amide, N-stearyl erucic acid amide, N-stearyl stearic acid amide, N-oleyl stearic acid amide, di- Complex higher fatty acid amides such as stearyl adipic amide; lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, behenic acid, oleic acid, linoleic acid, α-eleostearic acid, β-eleostearic acid Higher fatty acid salts such as lithium salts such as phosphoric acid and α-linoleic acid, sodium salts, potassium salts, magnesium salts, calcium salts, barium salts, zinc salts, aluminum salts, iron salts; polyacrylamide, polyvinyl chloride, polystyrene, Examples thereof include polyolefins such as high-density polyethylene, polymethylmethacrylate, polycarbonate, resin compounds such as styrene-acrylonitrile copolymer, and the like.

Examples of the inorganic anti-blocking agent include silica, calcium carbonate, magnesium carbonate, calcium sulfate, aluminum hydroxide, zinc oxide, talc and clay.

These anti-blocking agents may be used alone or in combination of two or more. Among these, the inorganic anti-blocking agent is preferable. The amount of the anti-blocking agent used is usually 0 to 100 parts by weight of the modifier.
The amount is 50 parts by weight, preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight.

The asphalt modifier of the present invention may further include, if necessary, antioxidants such as hindered phenols, sulfurs and phosphoric acids; ultraviolet absorbers such as benzophenone and the like; light stabilizers such as hindered amines. ; Natural rubber,
Polyisoprene rubber, polybutadiene rubber, random styrene-butadiene rubber, nitrile rubber, ethylene-
Rubbers such as propylene rubber, chloroprene rubber, acrylic rubber, and isoprene-isobutyl rubber; thermoplastic elastomers such as block copolymers other than the vinyl aromatic hydrocarbon / conjugated diene block copolymer of the present invention; ethylene / ethyl acrylate copolymer A thermoplastic resin such as a coalesced product, a polyolefin resin such as an ethylene / vinyl acetate copolymer, a polystyrene resin, or a polyvinyl chloride resin; an inorganic filler such as glass beads, silica, or carbon black; and the like can be added.

The method for producing the asphalt modifier of the invention is as follows:
A conventional method may be followed, for example, a heating and melting pot, a roll mill,
The above components can be mixed using a mixer such as a single-screw extruder, a twin-screw extruder or a Henschel mixer, and then molded by a press, a pelletizer, an extrusion molding machine, a processing molding machine or the like.

The method of mixing the respective components includes, for example, melt mixing and solvent dissolution mixing, and more specifically, (1) block copolymer, process oil and tackifying resin.
A method in which the components are heated and mixed in a heating and melting pot or a roll mill, (2) a method in which the above three components are premixed without heating and then heated and mixed in a single-screw extruder, and (3) a mixer such as a Henschel mixer In the method, the tackifying resin is crushed in the mixture, then the block copolymer is mixed, and finally the process oil is heated and mixed. (4) The block copolymer and the process oil are premixed, and then the tackifying resin And (5) a mixed block copolymer and a tackifying resin are heated and mixed by a twin-screw extruder, and a process oil is side-fed and mixed. Among these, the methods (3), (4) and (5) are particularly preferable for highly improving the solubility in asphalt. The heating and mixing is usually performed in the temperature range of 50 to 250 ° C, preferably 100 to 200 ° C.

The shape of the asphalt modifier of the present invention is not particularly limited, and any shape can be used. For example, it may be in the form of pellets, cords, plates, blocks, etc., but pellets are particularly preferable from the viewpoint of solubility in asphalt. Pelletization of the asphalt modifier can be achieved by mixing the above components, extruding them into a strand with an extruder or the like, cooling with cold water or the like, and then chopping them with a pelletizer or the like. It is preferable to sprinkle the strand before the pelletizer with a blocking-resistant agent because the shredder workability is further improved. The size of the pellet is 0.5
When it is -50 mm, preferably 1-20 mm, more preferably 2-10 mm, the solubility in asphalt is remarkably improved, which is preferable.

Asphalt composition The asphalt to be mixed with the modifier of the present invention is not particularly limited, and is a conventional asphalt, for example, straight asphalt, semi-blown asphalt, blown asphalt, asphalt emulsion or tar, pitch, You can use cut-back Alfalto with added oil, recycled asphalt, etc. These can be used alone or in combination of two or more. The asphalt may be decolorized asphalt.

The method for preparing the asphalt composition of the present invention is not particularly limited, and for example, each component may be heated in a hot melting pot, a wet mill, a high shear mixer, a roll, a kneader, a Banbury mixer, an extruder or the like. A method of heating, melting and kneading can be adopted. The compounding ratio of the asphalt modifier varies depending on the purpose of use and the type of asphalt, but is usually 0.5 to 500 parts by weight, preferably 1 to 100 parts by weight, and more preferably 3 to 50 parts by weight per 100 parts by weight of asphalt. The range is parts by weight.

The asphalt composition may be blended with additives commonly used in asphalt compositions. The additive is not particularly limited, and specific examples of the additive include aggregates such as crushed stone, crushed stone, gravel, sand, and recycled aggregate; fillers such as stone powder, talc, calcium carbonate; slaked lime, amines. , Amides and other peeling preventing agents; methyl cellulose, polyvinyl alcohol, and other fibrous reinforcing materials; elasticity improvers, viscosity reducers, viscosity improvers, fillers,
Pigments, softeners, antioxidants, UV absorbers, light stabilizers,
Examples thereof include rubber, other thermoplastic elastomers, and thermoplastic resins.

When the asphalt composition of the present invention is used for road paving, it is usually used as an asphalt mixture by mixing an aggregate and a filler. As aggregates and fillers (hereinafter, both are referred to as "aggregates"), for dense particle size, fine particle size or coarse particle size mixture used for general road pavement, water permeable pavement, drainage pavement,
Aggregates and fillers for open particle size mixtures such as those used for sound absorbing pavements are used. The composition of the asphalt mixture is usually 98-85% by weight of aggregate and 2% of asphalt.
１５15% by weight. The asphalt modifier is usually used within the range of the above blending ratio with respect to the asphalt. The above-mentioned additives can be added to the asphalt mixture, if necessary.

The mixing method is not particularly limited, and a premix system in which an asphalt composition containing an asphalt and an asphalt modifier prepared in advance and an aggregate are mixed, an asphalt modifier, an asphalt, and an aggregate. Although a method such as a plant mix method of mixing the above can be used, the plant mix method is a method in which the features of the present invention can be utilized more effectively. Examples of the plant mix method include (a) a method in which a filler, heated aggregate, and heated asphalt are mixed in advance, and then an asphalt modifier is added and mixed, (b) a filler, heated aggregate,
There are a method of mixing hot asphalt and an asphalt modifier at the same time, a method of (c) a filler, a heated aggregate, and an asphalt modifier are mixed in advance, and then a hot asphalt is added and mixed.

[0046]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. Parts and percentages in these examples are on a weight basis unless otherwise specified.

The methods for measuring physical properties are as follows. (1) Weight average molecular weight The weight average molecular weights of the block copolymer and the polyester were measured as standard polystyrene equivalents according to the GPC method. (2) Amount of bound styrene The amount of bound styrene (% by weight) of the block copolymer was calculated by the Hampton method using an infrared spectrophotometer.

(3) Solubility The solubility of the asphalt modifier in asphalt is
180 in accordance with the method for "preparing modified asphalt samples" described in the Pavement Test Method Manual established by the Japan Road Association.
The asphalt modifier was added to Alfalto heated to 0 ° C. and stirred, and the time (min) until there was no undissolved material was determined. (4) Penetration Penetration (1/10 mm) of the asphalt composition is JI
It was measured according to SK2207.

(5) Softening point The softening point (° C.) of the asphalt composition is JIS K220.
7 was measured. (6) Toughness and tenacity The toughness (kgf · cm) and tenacity (kgf · cm) of the asphalt composition were measured according to the method described in “Handbook of Pavement Test Methods” edited by the Japan Road Association.

(7) Viscosity at 60 ° C. The viscosity at 60 ° C. (poise) of the asphalt composition was measured according to the method described in “Handbook of Pavement Test Methods” edited by Japan Road Association. (8) Porosity The porosity (%) of the asphalt mixture was measured according to the method using calipers described in the supplementary items of the Japan Highway Public Corporation test method “JHS217-1992”.

(9) Dynamic Stability The dynamic stability of the asphalt mixture was determined by carrying out a wheel tracking test in accordance with the method described in "Handbook of Pavement Test Methods" edited by the Japan Road Association to determine the dynamic stability (time). / Mm) was calculated. (10) Aggregate scattering resistance (cantablo loss rate) The cantablo loss rate (%) of the asphalt mixture was measured according to the Japan Highway Public Corporation test method "JHS231-1992".

Examples 1 to 7 and Comparative Examples 1 to 3 The following tests were carried out in accordance with the materials and formulation shown in Table 1. The tackifying resin was placed in a 200 liter Henschel mixer and stirred at low speed (25 Hz) for 5 minutes. Next, after adding the block copolymer and stirring for 1 minute, the process oil was gradually added and stirred at high speed (35 Hz) for 9 minutes. At this time, the temperature of the mixture reached 52 ° C. The mixture is
Cool down to 42 ° C with a ribbon blender and bag into 2
After curing for one day, it was extruded into a string shape using a 65 mmφ single screw extruder, cooled in a cooling tank at a water temperature of 15 ° C., sprinkled with 1% by weight of calcium carbonate, and then a water-cooled pelletizer equipped with a rotary blade for 3
The pellet was cut into mmφ × 4 mm.

(Workability test) The adherence of the modifying material to the rotary blade was observed when the pelletizer was operated for 10 minutes, and evaluated according to the following three-stage criteria. The results are shown in Table 1. ◯: No adhesion is observed Δ: Several pellets are recognized on the rotary blade, but 1
Run for 0 minutes x: Strand wrapped around the blade and stopped without running for 10 minutes

(Evaluation of Storage Mutual Compatibility) The above modifier pellet 1
Put 20g in a plastic bag of 7 × 10cm ² and get 50g /
A load of cm ² was applied, and the state after standing still in an oven at 90 ° C. for 3 hours was evaluated according to the following three-stage criteria. Table 1 shows the results
It was shown to. ◯: No mutual adhesion Δ: Mutually adhered to each other, but quickly collapses when pressed with a finger ×: Mutually adhered to each other and does not collapse even when pressed with a finger

(Evaluation of Binder Property) In a 1 liter glass container, the above-mentioned modifier pellets were added to straight asphalt (60/80) heated to 180 ° C. at the compounding ratio shown in Table 1 and completely dissolved. Stirring was continued until the binder was prepared, and the properties of each binder were measured. Table 1 shows the time until dissolution and the properties of each binder.

(Evaluation of Properties of Mixture) 95.0 parts of aggregates for an open particle size asphalt mixture (composition: crushed stone No. 6 85% by weight, sand 10% by weight, stone powder 5% by weight) preheated to 190 ° C. with a pug mill mixer Dry asphalt (60/60
80) was added and mixed for 1 minute, then each modifier was added and mixed for another 1 minute. The total amount of the straight asphalt and the modifier was 50 parts, and their compounding ratio was as shown in Table 1. Immediately put the obtained mixture at 180 ° C. in a mold and use a roller compactor to obtain a linear pressure of 30 kgf.
The sample was compacted 25 reciprocations (/ 50 times) at / cm to obtain a sample.
A wheel tracking test was conducted using this test piece. The results are shown in Table 1. Also, the temperature of the mixture obtained by mixing in the same manner as above was adjusted to 160 ° C., and 50 pieces on each side were tamped using a Marshall sample preparation device.
A test piece was created. After measuring the porosity of this test piece, a cantablo test was performed. The results are shown in Table 1.

(Workability) A mixture having the same composition as that used in the mixture test was prepared as follows. That is, it was prepared by mixing the heated aggregate for 5 seconds in an 800 kg mixer, introducing the modifier mixture, mixing for another 5 seconds, then injecting asphalt, and further mixing for 40 seconds. The temperature of the prepared mixture was 180 ° C. The workability of the mixture was evaluated by the adhesion to the dump bed and the adhesion to the rollers as described below. The mixture is 5
Batch prepared.

The above mixture was loaded on a dump truck, covered with a cloth to keep it warm, and transported to the construction site for 30 minutes. The mixture was transferred to the asphalt finisher MF55WH manufactured by Mitsubishi Heavy Industries by tilting the bed of the dump truck. At this time, the adhesion of the mixture on the dump bed was evaluated and shown based on the following two-step criteria. The results are shown in Table 1. ○ No adhesion to the dump bed (dirty asphalt but no aggregate) × Adhesion to the dump bed (aggregate adheres and lumps are seen)

The above mixture was laid with an asphalt finisher to a thickness of 5 cm, leveled, and then subjected to 5 reciprocations with a Sadaka Heavy Industries Madam Roller R2 for the first rolling. The surface temperature at this time was 165 ° C. Adhesion to a madacam roller was evaluated based on the following criteria when the rolling was completed. The results are shown in Table 1. ○ No adhesion to rollers × Adhesion to rollers (agglomeration of mixture)

Further, after confirming that the surface temperature became 60 ° C. or lower, tire roller TS200 manufactured by Sakai Heavy Industries Co., Ltd.
2 reciprocations and secondary compaction were performed, and the construction was completed.

[0061]

[Table 1]

* 1 a: Styrene-butadiene block copolymer (bound styrene content = 31% by weight, molecular weight = 40)
50,000, (AB) ₄ -Si type) b: styrene / butadiene block copolymer (bound styrene amount = 30% by weight, molecular weight = 220,000, AB
-A type) * 2 c: Tosoh Petcoal 130 (C9 petroleum resin) d: Nippon Oil Co., Ltd. neopolymer 160 (C9 petroleum resin) * 3 e: Idemitsu Kosan Diana Process Oil PW
-90 f: PUREX12 manufactured by Exxon Corporation g: Process oil manufactured by Idemitsu Kosan PW-32 h: Process oil manufactured by Idemitsu Kosan NS-100 i: Process oil manufactured by Idemitsu Kosan AE-200 j: Process oil manufactured by Idemitsu Kosan AE -50

As shown in Table 1, when an asphalt modifier containing a process oil having a high aromatic component content was used as a process oil (Comparative Examples 1 and 2), the processability of the asphalt modifier was high. (Adhesion to the rotary blade of the pelletizer)
And storability (mutual adhesion of modifier pellets) is poor, and
The asphalt composition containing the modifier has poor workability (adhesion to the roller and adhesion to the dump bed). When a small amount of such an asphalt modifier containing a process oil having a high aromatic content is used (Comparative Example 3), the processability and storability of the asphalt modifier as described above and the asphalt composition of Although the workability is improved, the solubility in asphalt is lowered, the softening point, toughness, tenacity and other binder properties of the asphalt composition and the dynamic stability of the asphalt composition containing aggregates are inferior.

In contrast to the above, the asphalt modifiers of the present invention (Examples 1 to 7) have high solubility in asphalt, good processability and storability, and an asphalt composition containing the modifier. The binder properties of the product are generally good, and the asphalt composition containing the aggregates is excellent in porosity, dynamic stability, scattering resistance of the aggregate and workability.

[0065]

[Embodiment] 100 parts by weight of vinyl aromatic hydrocarbon / conjugated diene block copolymer, tackifying resin 10 to 300
Parts by weight, and 10-300 parts by weight of process oil having an aromatic content of 0-40% by weight, and an asphalt modifier of the invention comprising asphalt and the above-mentioned asphalt modifier. The preferred embodiments of the asphalt composition are summarized as follows.

(1) The vinyl aromatic hydrocarbon / conjugated diene block copolymer exceeds the vinyl aromatic hydrocarbon by 50% by weight, preferably 60 to 100% by weight, more preferably 70 to 100% by weight, and further preferably Is 80-100
Polymer block (A) 5 to 95 contained in a weight percentage
% By weight, preferably 10-50% by weight, more preferably 15-45% by weight and conjugated diene in excess of 50% by weight, preferably 60-100% by weight, more preferably 70-1.
The polymer block (B) contained in an amount of 00% by weight, more preferably 80 to 100% by weight, is 95 to 5% by weight, preferably 90 to 50% by weight, more preferably 85 to 55%.
It consists of wt.%.

(2) The vinyl aromatic hydrocarbon / conjugated diene block copolymer has a structure represented by any of the following general formulas (a) to (f). (A) (AB) m (b) (AB) nA (c) (BA) mB (d) ((AB) n) p-X (e) (( B-A) m) p-X (f) ((A-B) n-A) p-X (to) ((B-A) n-B) p-X

In these general formulas, A is a polymer block (A) mainly containing vinyl aromatic hydrocarbons,
B is a polymer block (B) mainly containing a conjugated diene, X is a residue of a polyfunctional coupling agent or a residue of a polyfunctional initiator, m is an integer of 1 or more, and preferably 2 or more. Is an integer of 2 to 6, more preferably an integer of 2 to 6, and n is 1
The above integers are preferably integers of 1 to 6, more preferably 1, and p is an integer of 2 to 6.

(3) The composition ratio (weight ratio) of vinyl aromatic hydrocarbon and conjugated diene in the block copolymer is 5:95.
~ 95: 5, more preferably 10:90 to 50:50,
Most preferably, it is in the range of 15:85 to 45:55.

(4) The molecular weight of the vinyl aromatic hydrocarbon / conjugated diene block copolymer is 10,000 to 100 as a polystyrene-reduced weight average molecular weight measured by GPC.
000, preferably 20,000 to 800,00
It is 0, more preferably 50,000 to 500,000.

(5) The vinyl bond amount of the conjugated diene portion of the vinyl aromatic hydrocarbon / conjugated diene block copolymer is 9
0% or less, preferably 1 to 60%, more preferably 5
-30%.

(6) The vinyl aromatic hydrocarbon constituting the block copolymer is styrene, α-methylstyrene, o-
It is selected from methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, and vinylanthracene, and styrene is particularly preferable, and a conjugation that constitutes a block copolymer. Diene is 1,3-butadiene, isoprene, 2,3
-Dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, preferably 1,3-butadiene or isoprene, more preferably 1,3-butadiene.

(7) A vinyl aromatic hydrocarbon / conjugated diene block copolymer is added to a reaction product obtained by copolymerization of a vinyl aromatic hydrocarbon and a conjugated diene, and a metal compound, an unsaturated nitrile, or a dihalogenated compound. It is produced by adding a polyfunctional coupling agent selected from hydrocarbons, carboxylic acid esters, carboxylic acid halides and carbon tetrachloride.

(8) The vinyl aromatic hydrocarbon / conjugated diene block copolymer is an unsaturated carboxylic acid, an imino compound,
It is modified with a modifier selected from cyanamide compounds, aziridinyl compounds, and amide compounds. (9) The aromatic oil content in the process oil is 0 to 20% by weight, more preferably 0 to 10% by weight.

(10) The process oil contains a naphthene component and a paraffin component in a weight ratio of 10 to 90:90 to 10, more preferably 20 to 50:80 to 50. (11) The amount of the process oil is 20 to 2 with respect to 100 parts by weight of the vinyl aromatic hydrocarbon / conjugated diene block copolymer.
00 parts by weight, more preferably 50 to 150 parts by weight.

(12) The tackifying resin is coumarone / indene resin, phenol resin, pt-butylphenol / acetylene resin, phenol / formaldehyde resin, terpene / phenol resin, polyterpene resin, xylene / formaldehyde resin, C5 petroleum resin. , C9
Selected from the group consisting of petroleum-based petroleum resins, dicyclopentadiene-based resins, polybutene, rosins, and hydrogenated and modified products thereof, more preferably C5-based petroleum resins, C9-based petroleum resins, and dicyclopentadiene-based resins. It is selected and more preferably C9 petroleum resin.

(13) The amount of tackifying resin is 20 to 200 parts by weight, more preferably 50 to 150 parts by weight, per 100 parts by weight of the block copolymer. (14) The asphalt modifier contains 50 parts by weight or less, and more preferably 0.1 to 10 parts by weight of a blocking resistance agent per 100 parts by weight of the modifier.

(15) The amount of the asphalt modifier in the asphalt composition is 100 parts by weight of the asphalt,
The amount is 0.5 to 500 parts by weight, more preferably 1 to 100 parts by weight, and further preferably 3 to 50 parts by weight. (16) The asphalt composition further contains 85 to 98% by weight of aggregate and filler (based on the total amount of aggregate and filler and asphalt).

[0079]

Since the asphalt modifier of the present invention has excellent solubility in asphalt, it can be easily dispersed uniformly in asphalt, and it is also excellent in processability and storage stability. The asphalt composition in which the asphalt modifier of the present invention is mixed with asphalt is excellent in binder properties such as penetration, softening point, toughness, tenacity, and 60 ° C. viscosity. Further, the asphalt mixture using the asphalt composition of the present invention is excellent in mixture properties such as porosity, dynamic stability, and aggregate scattering resistance, and is also excellent in workability. Therefore, the asphalt composition of the present invention can be used, for example, for road pavement, waterproofing, rust prevention, automobile undercoating, roofing, pipe coating, joint material, etc., depending on its composition and characteristics, and plasticity. It can contribute to improvement of resistance to deformation, improvement of impact resistance, improvement of durability, and the like.

Claims (2)

[Claims] 1. A vinyl aromatic hydrocarbon / conjugated diene block copolymer 100 parts by weight, a tackifying resin 10 to 30.
An asphalt modifier comprising 0 parts by weight and 10 to 300 parts by weight of process oil having an aromatic content of 0 to 40% by weight. 2. An asphalt composition containing asphalt and the asphalt modifier according to claim 1.