KR20180076827A - Asphalt modifier and modified asphalt composition comprising the same - Google Patents

Abstract

The present invention relates to an asphalt modifier and a modified asphalt composition having the same. The asphalt modifier comprises vinyl aromatic hydrocarbon-conjugated diene block copolymer mixtures of a trimeric type, a dimeric type, and a diblock structure. When using an asphalt modifier including 50 wt% or more of the block copolymer of a dimeric type in the total mixture, the present invention effectively improves low-temperature properties, high-temperature properties, and storage stability of the asphalt composition by including excellent compatibility with the asphalt composition.

Description

[0001] ASPHALT MODIFIER AND MODIFIED ASPHALT COMPOSITION COMPRISING THE SAME [0002]

The present invention relates to an asphalt modifier which is excellent in compatibility with asphalt and can improve the thermal stability of the asphalt, and a modified asphalt composition containing the same.

Asphalt is a residue of volatile oil components in petroleum which is mostly evaporated. It maintains a viscous liquid or semi-solid state at high temperature, but has a hard setting property at a temperature below room temperature.

Since asphalt is rich in plasticity, has high waterproofness, electrical insulation and adhesiveness, and is chemically stable, it is widely applied to building materials such as road pavement materials and waterproofing materials. However, asphalt has plastic deformation when it is exposed to high temperature for a long time during use and cracks due to external impact at low temperature. In order to solve these problems, various studies have been made to improve the physical properties of the asphalt composition by adding various polymers.

Specifically, a vinyl aromatic hydrocarbon-conjugated diene block copolymer such as styrene butadiene styrene (SBS) block copolymer is widely used as a modifier for improving physical properties of an asphalt composition.

When vinyl aromatic hydrocarbon-conjugated diene block copolymer is used as an asphalt modifier, much time and cost are required for dissolving at a high temperature. Therefore, the most important physical properties of the block copolymer used as the asphalt modifier are compatibility with the asphalt composition.

However, due to the recent rise in crude oil prices and energy conservation policies, the refining facility has been continuously upgraded, and asphaltene, a by-product of refinery oil, is rising. Asphaltenes are an aggregate of aromatic hydrocarbons and contain a large number of polar functional groups at their terminals, and thus have poor compatibility with block copolymers having no polar functional group. This not only significantly prolongs the processing time or production time of the asphalt, but also causes deterioration of the quality of the asphalt, such as reducing the elasticity and high temperature properties of the modified asphalt.

Therefore, in order to increase the compatibility with the asphalt composition, it is necessary to change the microstructure of the block copolymer so as to control the molecular weight of the SBS block copolymer or to add a coupling effect, or to add various additives such as oil as a processing aid .

For example, Korean Patent Laid-Open Publication No. 2016-0052310 discloses a process for producing an asphalt composition by using a vinyl aromatic hydrocarbon-conjugated diene block copolymer containing a specific amount of a different kind of conjugated diene block having a peak molecular weight (M _p ) Compatibility and physical properties of the asphalt can be improved.

Korean Patent Laid-Open Publication No. 2015-0102869 discloses a process for producing an asphalt modifier which comprises kneading a functionalized vinyl aromatic hydrocarbon-conjugated diene block copolymer having an aldehyde group bonded to a main chain of a conjugated diene block as an asphalt modifier, And improve storage stability.

These patents have improved the compatibility with the asphalt composition to some extent, but the effect is not sufficient. In addition, since the quality variation of asphalt according to the crude oil is large and the modification effect obtained by this is also different, it is not the ultimate solution. Therefore, further studies on vinyl aromatic hydrocarbon-conjugated diene block copolymer as an asphalt modifier having excellent compatibility with an asphalt composition and excellent reforming performance are further needed.

Korean Patent Laid-Open Publication No. 2016-0052310 (May 2015), an asphalt modifier and an asphalt composition containing the same Korean Patent Publication No. 2015-0102869 (2015.09.08), a functionalized vinyl aromatic hydrocarbon-conjugated diene block copolymer composition, a process for producing the same, and an asphalt composition containing the same

Accordingly, the present inventors have conducted various studies to solve the above-mentioned problems, and as a result, they have found that a mixture of a block copolymer having a triplet branched structure, a double branched branched structure and a diblock structure is included and the double branched block copolymer is contained It is confirmed that the compatibility with the asphalt composition is improved and the effect of improving the high temperature property of the asphalt can be enhanced.

Accordingly, an object of the present invention is to provide an asphalt modifier capable of simultaneously improving the solubility and thermal stability of an asphalt composition.

It is another object of the present invention to provide a process for producing the asphalt modifier.

It is still another object of the present invention to provide a modified asphalt composition comprising the asphalt modifier.

In order to achieve the above object, the present invention provides a tri-branched vinyl aromatic-conjugated diene block copolymer represented by the following formula (1): A double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (2); And a diblock vinyl aromatic-conjugated diene block copolymer represented by the following formula (3), wherein the block copolymer of the following formula (2) is contained in an amount of 50% by weight or more in the total mixture:

[Chemical Formula 1]

(2)

(3)

(In the above formulas (1) to (3), Q, R ₁ to R ₇ , X and p are as described in the specification.)

Wherein R ₁ is a C ₁ to C 6 alkyl group, a C ₁ to C 10 haloalkyl group, a C 3 to C 10 cycloalkyl group, or a C 6 to C 15 aryl group, and p is 0.

The tri-branched vinyl aromatic-conjugated diene block copolymer of Formula 1 is contained in an amount of 10 to 35% by weight in the total mixture.

And the double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 2 is contained in an amount of 55 to 80 wt% in the entire mixture.

The diblock vinyl aromatic-conjugated diene block copolymer of Formula 3 is contained in an amount of 5 to 25% by weight in the entire mixture.

The present invention also provides a method for producing a vinyl aromatic hydrocarbon-conjugated diene block copolymer, which comprises mixing and polymerizing a vinyl aromatic hydrocarbon monomer, a conjugated diene monomer and a polymerization initiator to prepare a vinyl aromatic hydrocarbon-conjugated diene block copolymer;

The block copolymer is mixed with a trifunctional silane coupling agent, and through a coupling reaction,

Comprising the steps of: preparing a mixture comprising a tri-branched vinyl aromatic hydrocarbon-conjugated diene block copolymer, a double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer, and a diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer; A method for producing an asphalt modifier is provided.

The trifunctional silane coupling agent is added in an amount of 2.0 to 3.0 molar equivalents based on 1 molar equivalent of the polymerization initiator.

The trifunctional silane coupling agent may be selected from the group consisting of trichloro (methyl) silane, trichloro (ethyl) silane, trichloro (propyl) silane, trichloro (butyl) silane, trichloro (decyl) silane, trichloro (cyclohexyl) silane , Trichloro (phenyl) silane, trichloro-3-chloropropyl silane, trichloro (trifluoromethyl) silane, trichloro (trifluoroethyl) silane, trichloro (trifluoropropyl) silane, trichloro (1H, 1H, 1H, 2H, 2H-tridecafluoro-n-octyl) silane and trichloro do.

In addition, the present invention provides a modified asphalt composition comprising asphalt, a crosslinking agent and the asphalt modifier.

The asphalt modifier according to the present invention includes a vinyl aromatic hydrocarbon-conjugated diene block copolymer having a tri-branched structure, a double branched structure and a diblock structure, and the compatibility of the asphaltene block copolymer with asphalt And the use thereof in the asphalt composition not only greatly improves workability but also can effectively modify various physical properties such as low temperature and high temperature physical properties and storage stability of the asphalt.

Hereinafter, the present invention will be described in more detail.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be understood in terms of meaning and concept in accordance with the technical idea of the present invention.

In order to improve the physical properties of the asphalt composition, a vinyl aromatic hydrocarbon-conjugated diene block copolymer is used as an asphalt modifier.

The asphalt composition is composed of four major components. Asphalt is the most miscible component of the asphalt modifier, vinyl aromatic hydrocarbon-conjugated diene block copolymer. Asphaltenes are highly concentrated aromatic hydrocarbon compounds with polar functional groups that contain many heteroatoms chemically. The vinyl aromatic hydrocarbon-conjugated diene block copolymer, which is conventionally used as an asphalt modifier, has poor compatibility with the asphalt composition because of the absence of polar functional groups, resulting in poor processability and workability. In addition, the asphalt modifier is not sufficiently incorporated into the asphalt composition, which causes problems such as elasticity and softening point of the asphalt.

In order to improve this, a method of changing the constitution or molecular weight range of the block copolymer, introducing a hydrophilic functional group into the block copolymer, or adding an oil has been used. However, since the molecular weight of the block copolymer is reduced by the breakage of the chain, There arises a problem that the physical properties of the asphalt composition are rather lowered.

Accordingly, the present invention includes a vinyl aromatic hydrocarbon-conjugated diene block copolymer having three polyfunctional functional groups in order to ensure excellent compatibility with asphalt and heat stability, and a double-branched vinyl (di-arm) An asphalt modifier comprising an aromatic hydrocarbon-conjugated diene block copolymer in a specific content range is presented.

Specifically, the asphalt modifier according to the present invention comprises a tri-branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (1); A double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (2); And a diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (3):

[Chemical Formula 1]

(2)

(3)

(In the above Formulas 1 to 3,

이고, Q each independently

ego,

Herein, A to C blocks are, independently of each other, a vinyl aromatic hydrocarbon block or a conjugated diene block, m, n and o are integers of 1 or more,

X is a polar group,

R ₁ is selected from a C1 to C20 alkyl group, a C1 to C20 haloalkyl group, a C3 to C20 cycloalkyl group or a C6 to C20 aryl group,

R ₂ to R ₇ are the same or different from each other and each independently represents a C1 to C10 alkylene group,

and p is an integer of 0 or 1.)

The term " alkyl group " used in the present invention may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 20, Specific examples include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl and heptyl.

The term " haloalkyl group " as used in the present invention means an alkyl group substituted with halogen unless otherwise stated.

The term " halogen " as used herein is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) unless otherwise stated.

The term " cycloalkyl group " as used herein refers to a non-aromatic carbon-based ring consisting of at least three carbon atoms. For example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and the like, but are not limited thereto.

The term " alkylene group " used in the present invention means a divalent alkyl group, which may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 20, Examples thereof include, but are not limited to, methylene, ethylene, n-propylene, iso-propylene, n-butylene and the like.

The term " aryl group " used in the present invention means a single or multiple aromatic carbon-based ring having 6 to 20 carbon atoms. For example, a phenyl group, a biphenyl group, a fluorene group and the like, but are not limited thereto.

As described above, the asphalt modifier of the present invention comprises a trifunctional tri-arm vinyl aromatic-hydrocarbon-conjugated diene block copolymer represented by the above formula (1), which contains a polyfunctional functional group derived from a coupling agent, And a diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the general formula (3). The di-arm vinyl-aromatic hydrocarbon-conjugated diene block copolymer represented by the general formula (1)

The tri-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of the above formula (1) has a structure in which a double bond existing in the conjugated diene block is broken by deterioration as compared with a block copolymer used in a conventional asphalt modifier, Since the effect of decreasing the molecular weight and the softening point is minimized, the softening point is stably maintained to improve the thermal stability of the asphalt composition.

The content of the tri-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 1 is 10 to 35% by weight, preferably 12 to 30% by weight, based on 100% by weight of the total of the block copolymer mixture. . When the amount falls within the above range, the effect on the asphalt due to deterioration is reduced, so that the high-temperature properties of the asphalt can be improved.

The di-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 2 includes a polyfunctional functional group-containing polar group derived from a coupling agent, thereby providing excellent reactivity with the polar group of the asphalt, And high compatibility. This improvement in compatibility also leads to an increase in solubility. The polar group may be a hydroxyl group (-OH) or a carboxyl group (-COOH). At this time, the solubility characteristics can be confirmed by the phase separation test, and it can be confirmed that according to the following Table 1, the solubility is higher than that of the conventional asphalt modifier. In addition to this, the di-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 2 may be used together with the tri-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 1 described above Thereby improving the thermal stability.

The content of the di-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 2 may be 50% by weight or more, preferably 55 to 80% by weight based on 100% by weight of the total of the block copolymer mixture. have. If it is within the above range, the compatibility with asphalt and the heat stability can be improved, and the overall physical properties such as elasticity, strength, service life and temperature range of asphalt can be improved.

The diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 3 contains two hydroxyl group (-OH) groups, which are polar functional groups derived from a coupling agent and are polar functional groups, Thereby further improving the reactivity.

The content of the diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 3 may be 5 to 25% by weight, preferably 10 to 25% by weight based on 100% by weight of the entire block copolymer mixture. When the amount falls within the above range, compatibility with asphalt can be increased and sufficient reforming performance can be obtained.

Particularly, the asphalt modifier of the present invention is preferably used in an amount of not less than 50% by weight based on 100% by weight of the total of the block copolymer mixture, of the double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the above formula (2) By weight, preferably 55 to 85% by weight, the effect of simultaneously improving the solubility and the softening point can be obtained.

The vinyl aromatic hydrocarbon block is a polymer unit moiety composed of a vinyl aromatic C6-C30 aromatic hydrocarbon compound such as styrene, vinyl naphthalene, vinyl toluene, or vinyl xylene. Preferably, the vinyl aromatic hydrocarbon block may be a polystyrene block comprising a structure derived from a styrene compound. For example, the vinyl aromatic hydrocarbon block may be selected from the group consisting of styrene; C1 to C20 alkyl) styrenes such as alpha (alpha) -methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene and the like; C3 to C30 cycloalkyl) styrenes such as 4-cyclohexyl styrene; And aryl styrenes of C7 to C30, such as C6-C30 arylstyrenes such as 4- (para-methylphenyl) styrene, and the like.

The maximum peak molecular weight (M _p ) of the vinyl aromatic hydrocarbon block may be 3,000 to 35,000 g / mol, preferably 10,000 to 25,000 g / mol. When the vinyl aromatic hydrocarbon block falls within the above range, the low temperature properties can be improved while maintaining the high temperature properties and storage stability of the asphalt.

The conjugated diene block may include a structure derived from a butadiene compound as a diolefin having a pair of conjugated double bonds. For example, the conjugated diene block may be selected from the group consisting of 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 3-butyl-1,3-octadiene, 1,3-pentadiene, 1,3-hexadiene, and 2-phenyl-1,3-butadiene.

The maximum peak molecular weight (M _p ) of the conjugated diene block may be 10,000 to 150,000 g / mol, preferably 20,000 to 100,000 g / mol. When the maximum peak molecular weight (M _p ) of the conjugated diene block is less than the above range, the mechanical properties of the block copolymer may not be easily manifested. On the contrary, if the conjugated diene block exceeds the above range, the workability may be deteriorated.

More preferably, styrene or alpha-methylstyrene, 3-methylstyrene and 4-methylstyrene can be used alone or as a mixture of the vinyl aromatic hydrocarbons, and as the conjugated diene, there can be used butadiene or 2-methyl-1,3-butadiene Can be used alone or in combination.

The weight ratio of the vinyl aromatic hydrocarbon block to the conjugated diene block may be 1: 1 to 1: 4. When the weight ratio falls within the above range, it can be stably dissolved in the asphalt composition to obtain a sufficient reforming effect. If the content of the vinyl aromatic hydrocarbon is less than the above range, the physical properties of the asphalt deteriorate because the vinyl aromatic hydrocarbon block hardly forms a physical crosslinking point. On the other hand, when the content exceeds the above range, the solubility in asphalt is poor and the low- .

The block copolymer represented by the [ABC] block may be a linear, branched, symmetric, asymmetric or radial type styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), or styrene- A block copolymer may be used, or two or more of these may be used in combination. Preferably, it may be styrene-butadiene-styrene (SBS) or styrene-butadiene (SB), and more preferably styrene-butadiene (SB).

The block copolymer represented by the [ABC] block may have a maximum peak molecular weight (M _p ) of 15,000 to 1,000,000 g / mol, preferably 30,000 to 800,000 g / mol, and may be linear, branched, . When the molecular weight of the vinyl aromatic hydrocarbon-conjugated diene block copolymer is less than the above-mentioned range, the molecular weight of the vinyl aromatic hydrocarbon block is too small to cause deterioration of high-temperature properties. On the other hand, when the molecular weight exceeds the above range, solubility in asphalt It falls out.

The present invention also provides a method for producing the aforementioned asphalt modifier.

The method for producing an asphalt modifier according to the present invention comprises mixing and polymerizing a vinyl aromatic hydrocarbon monomer, a conjugated diene monomer and a polymerization initiator to prepare a vinyl aromatic hydrocarbon-conjugated diene block copolymer;

The block copolymer is mixed with a trifunctional silane-based coupling agent and prepared by a coupling reaction.

Through the above steps, an asphalt modifier in the form of a mixture comprising a tri-branched vinyl aromatic hydrocarbon-conjugated diene block copolymer, a double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer, and a diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer .

Hereinafter, a method for producing the asphalt modifier of the present invention will be described in detail.

First, the vinyl aromatic hydrocarbon monomer is subjected to a polymerization reaction using a polymerization initiator in a hydrocarbon-based solvent to prepare a vinyl aromatic hydrocarbon block.

The vinyl aromatic hydrocarbon monomer may include an aromatic hydrocarbon compound having a vinyl group containing C6 to C30 as described above. The vinyl aromatic hydrocarbon monomer may be used in an appropriate amount in consideration of the content of the vinyl aromatic hydrocarbon block in the finally produced vinyl aromatic hydrocarbon-conjugated diene block copolymer.

The hydrocarbon-based solvent does not react with the polymerization initiator described later, and can be used without particular limitation, as long as it is usually used in a polymerization reaction. For example, the hydrocarbon solvent may be a linear or branched hydrocarbon compound such as butane, n-pentane, n-hexane, n-heptane or isooctane; Alkyl substituted or unsubstituted cyclic hydrocarbon compounds such as cyclopentane, cyclohexane, cycloheptane, methylcyclohexane and methylcycloheptane; And alkyl substituted or unsubstituted aromatic hydrocarbon compounds such as benzene, toluene, xylene, naphthalene, and the like.

The hydrocarbon solvent may further include a polar solvent for controlling the vinyl content of the conjugated diene monomer and improving the polymerization rate. For example, the polar solvent may include at least one selected from the group consisting of tetrahydrofuran, ethyl ether, etramethylethylenediamine, and benzofuran.

The polymerization initiator can be generally used for the anionic polymerization without any particular limitation.

The polymerization initiator may be an organic metal compound or a living anion which is a polymer chain having an anionic end initiated from the polymerization initiator.

The organometallic compound may be an organolithium compound of the following formula (4): < EMI ID =

[Chemical Formula 4]

(In the formula 4,

R ₈ is a C1 to C20 alkyl group, a C3 to C20 cycloalkyl group, a C1 to C20 alkoxy group, a C6 to C20 aryl group or a C7 to C20 arylalkyl group.

The term " alkoxy group " used in the present invention means an alkyl group having 1 to 20 carbon atoms having an oxygen atom through an ether bond at the carbon chain terminal unless otherwise specified, but is not limited thereto.

The term " arylalkyl group " as used herein means an aryl group substituted with an alkyl group. Examples thereof include, but are not limited to, benzyl group, chlorobenzyl group,? -Methylbenzyl group,?,? - dimethylbenzyl group and the like.

For example, the organometallic compound can be prepared by reacting an organometallic compound with a compound selected from the group consisting of n-butyllithium, sec-butyllithium, tert-butyllithium, methyllithium, ethyllithium, isopropyllithium, cyclohexyllithium, allyl lithium, vinyllithium, And at least one selected from the group consisting of

Then, the vinyl aromatic hydrocarbon block, the polymerization initiator and the conjugated diene monomer are mixed and polymerized to prepare a vinyl aromatic hydrocarbon-conjugated diene block copolymer.

The conjugated diene monomer may be a butadiene-based compound as described above. The conjugated diene monomer may be used in an appropriate amount in consideration of the content of the conjugated diene block in the finally produced vinyl aromatic hydrocarbon-conjugated diene block copolymer.

The polymerization reaction of the conjugated diene can also be carried out by anionic polymerization reaction as in the above-mentioned step. Therefore, the polymerization initiator is as described above.

In the above-mentioned two-step polymerization, the polymerization initiator may be contained in an amount of 0.3 to 3.3 mmol based on the total content of the vinyl aromatic hydrocarbon-conjugated diene block copolymer. If the content of the polymerization initiator is less than the above range, the molecular weight becomes very large and the reaction efficiency of the reactor is lowered. As a result, the reaction with the coupling agent described below may not be performed well and it may be difficult to introduce a polyfunctional functional group. There is a disadvantage that productivity in the post-treatment process may be seriously deteriorated.

The polymerization reaction is preferably carried out at a temperature ranging from 0 to 150 ° C and a pressure range (0.1 to 10 bar) where the reactant can be maintained in a liquid state until the consumption rate of the conjugated diene monomer is 99% or more.

 Also, a vinyl aromatic hydrocarbon-conjugated diene block copolymer in which the above-mentioned vinyl aromatic hydrocarbon block and conjugated diene block are cross-aligned is prepared through the polymerization reaction, wherein at least one block of A to C blocks in the above formula It is preferable to include an aromatic hydrocarbon block.

Then, the vinyl aromatic hydrocarbon-conjugated diene block copolymer and the trifunctional silane coupling agent are mixed and subjected to a coupling reaction to prepare an asphalt modifier in the form of a mixture.

In the coupling reaction, a polyfunctional functional group is introduced into the vinyl aromatic hydrocarbon-conjugated diene block copolymer and the conjugated diene blocks are connected to each other to form a block copolymer represented by the following formulas (1) to (3).

The bifunctional silane-based coupling agent is not particularly limited as long as it is a silane-based compound having three reactors.

For example, the trifunctional silane coupling agent may be selected from the group consisting of trichloro (methyl) silane, trichloro (ethyl) silane, trichloro (propyl) silane, trichloro (butyl) silane, trichloro (decyl) silane, trichloro (cyclohexyl) silane, trichloro (butyl) silane, Trichloro (phenyl) silane, trichloro (3-chloropropyl) silane, trichloro (trifluoromethyl) silane, trichloro Trichloro (trifluoroethyl) silane, trichloro (trifluoropropyl) silane, trichloro (1H, 1H, 2H, 2H-tridecafluoro-n-octyl 2H-perfluoro-n-octyl) silane and trichloro (1H, 1H, 2H, 2H-perfluorodecyl) silane (Trichloro perf luorodecyl) silane). < / RTI > Preferably, the coupling agent is selected from the group consisting of trichloro (methyl) silane, trichloro (ethyl) silane, trichloro (propyl) silane, trichloro (phenyl) silane and trichloro (3- It can be more than a species.

The trifunctional silane-based coupling agent reacts with the anion active sites at the end of the block in the vinyl aromatic hydrocarbon-conjugated diene block copolymer prepared through the above-mentioned process to link the conjugated diene blocks between the block copolymers and to perform the functionalization Can be performed.

In particular, in the present invention, the trifunctional silane-based coupling agent may be added in an amount of 2.0 to 3.0 molar equivalents, preferably 2.0 to 2.6 molar equivalents based on 1 molar equivalent of the polymerization initiator used in the above step. Specifically, the asphalt modifier of the present invention may contain a di-arm vinyl aromatic hydrocarbon-conjugated diene block copolymer in an amount exceeding a certain level by introducing an excessive amount of the trifunctional silane coupling agent into the polymerization initiator .

The vinyl aromatic hydrocarbon-conjugated diene block copolymer of the above formulas (1) to (3) is prepared through the above coupling reaction. At this time, the resulting product obtained as a result of the coupling reaction may contain a mixture of the vinyl aromatic hydrocarbon-conjugated diene block copolymer not subjected to the coupling reaction.

The present invention also provides a modified asphalt composition comprising asphalt, a cross-linking agent, and the asphalt modifier described above.

The asphalt is a residue obtained by refining crude oil, which is mainly composed of hydrogen and carbon, and is composed of a hydrocarbon compound having a small amount of nitrogen, sulfur or oxygen bonded thereto. The asphalt is conventional and includes both natural and petroleum-derived asphalt and is not particularly limited. For example, the asphalt may be selected from the group consisting of natural asphalt, stright asphalt, blown asphalt, guss asphalt, cutback asphalt, emulsified asphalt, ) Grade asphalt, and the like, and may be preferably straight asphalt.

The straight asphalt contains a large amount of bitumen that is not decomposed as a final residue obtained by distillation of the crude oil by distillation under reduced pressure from the distillation column of the atmospheric distillation column, and can be used as a raw material for various petroleum-based asphalt. The above-mentioned straight asphalt can be directly manufactured through a method commonly used in the art, or a commercially available product can be used. Examples of commercially available straight asphalt include AP-3 and AP-5 supplied by SK Energy or GS Caltex.

The asphalt may comprise 1 to 40% by weight, specifically 5 to 30% by weight of asphaltenes in the total content.

The asphalt modifier is as described above for improving compatibility with asphalt and thermal stability.

The cross-linking agent serves to increase the compatibility of the asphalt modifier with the asphalt. The crosslinking agent is not particularly limited as long as it is a sulfur compound containing sulfur or iron sulfate, and representative examples thereof include a sulfur element.

As an example, the modified asphalt composition of the present invention may comprise 1 to 10 parts by weight of an asphalt modifier, 87 to 98.95 parts by weight of asphalt and 0.05 to 3 parts by weight of a crosslinking agent.

Within this range, excellent storage stability of the asphalt composition can be secured. If the content of the asphalt modifier exceeds the above range, the manufacturing cost of the modified asphalt composition increases, and when the content of the cross-linking agent exceeds the above range, the modified asphalt becomes less elastic due to excessive cross-linking reaction, gelation. On the other hand, when the content of each of the asphalt modifier and the cross-linking agent is less than the above range, the asphalt modifying degree is low and the physical properties and elasticity of the modified asphalt are deteriorated.

The modified asphalt composition of the present invention is obtained by blending the asphalt modifier, crosslinking agent and asphalt of the above formula (1) with asphalt with a high speed shear mixer and a low speed shear mixer.

The crosslinking agent is not particularly limited as long as it is a sulfur compound containing sulfur or iron sulfate, and representative examples thereof include a sulfur element.

When the modifier is contained in an amount of about 4 to 5% by weight under vulcanization conditions, the asphalt composition preferably has a melting rate of 1 to 10 hours, more preferably 1 to 8 hours. That is, the balance of physical properties of the asphalt composition is excellent within this range.

For example, the mixing process of the modified asphalt composition is as follows. The asphalt is put into a 1 L container and maintained at a temperature of 150 to 170 캜, preferably 160 to 165 캜 for 30 minutes to 2 hours, preferably for at least 40 minutes. When the asphalt is sufficiently melted, the asphalt modifier of the above formula The stirring speed is gradually increased. At this time, the speed of the high-speed shear mixer is maintained at 2,500 rpm and stirred for one hour while adjusting the temperature to 180 to 195 ° C, preferably to 190 ° C. Thereafter, the mixture is transferred to an impeller-type stirrer, maintained at 250 rpm at the same temperature, stirred for an additional 4 hours, preferably 5 to 8 hours, and the modified asphalt composition is sampled for a predetermined time to measure its physical properties. At this time, the modified asphalt composition is sampled by a predetermined time to measure the physical properties. Specifically, the modified asphalt composition was sampled in an aluminum tube for each mixing time and stored in an oven at 180 ° C for a certain period of time. Solubility was confirmed by difference in softening point between the upper and lower layers of the aluminum tube.

The modified asphalt composition of the present invention may have a viscosity range of a softening point of 65 ° C, an elongation of 20 cm or more, and a viscosity of 3,000 cPs or less. At this time, the elongation and viscosity are not limited to any specific range, and the elongation may be as large as 20 cm or more, and the viscosity may be preferably as small as 3,000 cPs or less. For example, the elongation may range from 20 to 80 cm, and the viscosity may range from 300 to 3,000 cPs, but is not limited thereto.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Example  1: Asphalt Modifier  And asphalt composition

(1) Asphalt Modifier  Produce

4,285 g of purified cyclohexane and 272.8 g of styrene were charged into a 10 L reactor purged with nitrogen, and the temperature was raised to 60 DEG C with stirring. 0.98 g of n-butyllithium was added to the mixed solution of cyclohexane and styrene to polymerize the styrene block. 607.2 g of butadiene was then added thereto, and polymerization was continued until the butadiene completely consumed.

After completion of the polymerization reaction, 1.34 g of trichloro (methyl) silane was added as a coupling agent to perform a coupling reaction.

Subsequently, 0.5 g of water was added as a reaction terminator to remove the reaction activity. Then, 6.16 g of a solution obtained by mixing a primary antioxidant and a secondary antioxidant as antioxidants was added to the polymerization solution. The resulting polymer sample was dissolved in tetrahydrofuran (THF) for 30 minutes and loaded on GPC (Gel Permeation Chromatography, waters). The polymer sample was compared with standard molecular weight of PS (polystyrene) Were measured. As a result, the maximum peak molecular weight was about 116 kg / mol, and the styrene block content was 29% by weight.

Next, in order to recover only the block copolymer in the reaction solution, a stripping process was generally performed. Specifically, 0.7 g of Tamol (BASF) as a dispersant and 0.5 g of CaCl ₂ were added to 3 L of water and boiled, and then the solution containing the block copolymer was slowly added to boiling water to coagulate the block copolymer in water . The coagulated block copolymer was dried in an oven at 60 DEG C for 16 hours to prepare a styrene-butadiene block copolymer pellet.

(2) Preparation of an asphalt composition

500 g of asphalt (AP-5, SK) was charged into a heating mantle and stirred at a high shear rate of 200 to 2,500 rpm, and the asphalt modifier prepared in Example 1 was added to the asphalt composition at a rate of 4.2 % ≪ / RTI > by weight.

Then, after 1 hour, the mixture was stirred at a low shear rate of 250 rpm. At this time, while observing the fluorescence microscope, the mixture was stirred until dissolving the SBS copolymer to prepare an asphalt composition.

Example  2: Asphalt Modifier  And asphalt composition

In the same manner as in Example 1, except that the amount of the coupling agent of Example 1 was changed to 1.43 g, a styrene-butadiene block having a maximum peak molecular weight of about 117 kg / mol and a styrene block content of 29 wt% To prepare a copolymer mixture. The content of each structure is shown in Table 1 below.

Subsequently, an asphalt composition was prepared in the same manner as in Example 1.

Example  3: Asphalt Modifier  And asphalt composition

In the same manner as in Example 1, except that the amount of the coupling agent of Example 1 was changed to 1.57 g, the maximum peak molecular weight was about 117 kg / mol and the styrene block content was 29 wt%. The styrene-butadiene block To prepare a copolymer mixture. The content of each structure is shown in Table 1 below.

Subsequently, an asphalt composition was prepared in the same manner as in Example 1.

Example  4: Asphalt Modifier  And asphalt composition

In the same manner as in Example 1, except that the amount of the coupling agent of Example 1 was changed to 1.71 g, the maximum peak molecular weight was about 117 kg / mol and the styrene block content was 29 wt%. The styrene-butadiene block To prepare a copolymer mixture. The content of each structure is shown in Table 1 below.

Subsequently, an asphalt composition was prepared in the same manner as in Example 1.

Comparative Example  1: Asphalt Modifier  And asphalt composition

The maximum peak molecular weight was about 100 kg / mol in the same manner as in Example 1, except that 0.96 g of dichlorodimethylsilane was used instead of trichloro (methyl) silane as the coupling agent of Example 1, A linear styrene-butadiene block copolymer having a styrene block content of 31.4 wt% and a coupling efficiency of 86.7% was prepared. The content of each structure is shown in Table 1 below.

Subsequently, an asphalt composition was prepared in the same manner as in Example 1.

Comparative Example  2: Asphalt Modifier  And asphalt composition

The maximum peak molecular weight was about 116 kg / mol and the styrene block content was 29% by weight in the same manner as in Example 1, except that the amount of the coupling agent in Example 1 was changed to 1.25 g. To prepare a copolymer mixture. The content of each structure is shown in Table 1 below.

Subsequently, an asphalt composition was prepared in the same manner as in Example 1.

Experimental Example  1: Evaluation of physical properties of modified asphalt composition

The properties of the asphalt modifier and the modified asphalt composition prepared in the above Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 1 below.

(1) Toluene Solution Viscosity (Toluene Solution Viscosity; TSV )

Viscosity was measured at 25 캜 after dissolving the asphalt modifier prepared in the above Examples and Comparative Examples at 5 v / v% on toluene.

(2) Softening point

The softening point is a measure of the high temperature properties of modified asphalt measured according to ASTM (American Society for Testing and Materials) D36. When the specimen starts to soften at 5 ° C / min in water or glycerin heating, the diameter of 9.525 mm, The temperature was measured when the beads of g were squeezed by one inch.

(3) Phase separation  Temperature

50 g of the modified asphalt composition was added to the aluminum tube, and the mixture was allowed to stand in an oven at 180 캜 for 72 hours. The upper and lower softening points of the upper and lower portions were measured by the ASTM D36 method and the temperature difference was calculated.

(4) Shindo

Shindo is a low temperature property measure of modified asphalt measured in accordance with ASTM D 113. When the specimen is pulled in both directions in a thermostatic chamber maintained at 5, the elongation length was measured until the specimen was broken.

Polymerization initiator: coupling agent The ratio of the formula (1) / (2) /
(weight%) TSV
(cSt) Softening point
(° C) Phase separation temperature
(T, ° C) 5 Shindo
(Mm) Example 1 1: 2.0 25.1 / 62.9 / 9.3 18.9 95.6 12.3 281.5 Example 2 1: 2.2 26.5 / 59.4 / 12.2 18.0 94.3 10.2 290.0 Example 3 1: 2.4 18.5 / 62.4 / 17.3 16.2 93.0 6.2 301.0 Example 4 1: 2.6 13.9 / 63.6 / 20.5 15.8 92.7 5.1 326.0 Comparative Example 1 1: 1 0 / 84.1 / 15.9 15.7 90.4 9.2 292.0 Comparative Example 2 1: 1.8 43.3 / 46.6 / 10.6 19.2 96.3 15.3 270.0

As shown in Table 1, the modified asphalt composition containing the asphalt modifier according to the present invention is superior to the modified asphalt composition of Comparative Example 1 in that the basic physical properties of modified asphalt such as softening point and elongation are excellent and the phase separation temperature is significantly lowered It was confirmed that the solubility in the asphalt composition was greatly improved.

According to the present invention, a styrene-butadiene block copolymer having a tri-arm, a di-arm and a diblock structure is included, and a double-arm block copolymer Of the modified asphalt compositions of Examples 1 to 4 having a certain amount or more is higher than that of Comparative Examples. In addition, it can be seen that the phase separation temperature is reduced by about 40% or more as compared with Comparative Example 1 under the same agitation time. As a result, it can be confirmed that the modified asphalt composition according to the present invention has excellent solubility and thermal stability.

The asphalt modifier of the present invention has high compatibility with the asphalt composition and can provide an asphalt composition having excellent low temperature and high temperature properties, storage stability and reforming workability.

Claims (12)

A tri-branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (1);
A double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (2); And
A diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer represented by the following formula (3)
An asphalt modifier characterized in that the block copolymer of the following formula (2) is contained in an amount of 50% by weight or more in the entire mixture:
[Chemical Formula 1]

(2)

(3)

(In the above Formulas 1 to 3,
Q each independently

ego,
Wherein A to C blocks are, independently of each other, a vinyl aromatic hydrocarbon block or a conjugated diene block, m, n and o are integers of 1 or more,
X is a polar group,
R ₁ is selected from a C1 to C20 alkyl group, a C1 to C20 haloalkyl group, a C3 to C20 cycloalkyl group or a C6 to C20 aryl group,
R ₂ to R ₇ are the same or different from each other and each independently represents a C1 to C10 alkylene group,
and p is an integer of 0 or 1.) The method according to claim 1,
Wherein R ₁ is a C1 to C6 alkyl group, a C1 to C10 haloalkyl group, a C3 to C10 cycloalkyl group or a C6 to C15 aryl group,
and p is 0. The method according to claim 1,
Wherein the triplet branched vinyl aromatic-conjugated diene block copolymer of Formula 1 is contained in an amount of 10 to 35% by weight in the total mixture. The method according to claim 1,
Wherein the double branched vinyl aromatic hydrocarbon-conjugated diene block copolymer of Formula 2 is contained in an amount of 55 to 80 wt% in the entire mixture. The method according to claim 1,
Wherein the diblock vinyl aromatic-conjugated diene block copolymer of Formula 3 is contained in an amount of 5 to 25 wt% in the total mixture. The method according to claim 1,
The vinyl aromatic hydrocarbon block may be at least one selected from the group consisting of styrene, alpha-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene and 4- (para- And an asphalt modifier. The method according to claim 1,
Wherein the conjugated diene block comprises at least one member selected from the group consisting of 1,3-butadiene, 2,3-dimethyl-1,3-butadiene and 2-phenyl-1,3-butadiene. The method according to claim 1,
Wherein the maximum peak molecular weight of the asphalt modifier is from 15,000 to 1,000,000 g / mol. Mixing a vinyl aromatic hydrocarbon monomer, a conjugated diene monomer and a polymerization initiator and polymerizing them to prepare a vinyl aromatic hydrocarbon-conjugated diene block copolymer;
The block copolymer is mixed with a trifunctional silane coupling agent, and through a coupling reaction,
Comprising preparing a mixture comprising a tri-branched vinyl aromatic hydrocarbon-conjugated diene block copolymer, a double branched vinyl aromatic-hydrocarbon conjugated diene block copolymer, and a diblock vinyl aromatic hydrocarbon-conjugated diene block copolymer Wherein the asphalt modifier is a polyolefin. 10. The method of claim 9,
Wherein the trifunctional silane coupling agent is added in an amount of 2.0 to 3.0 molar equivalents based on 1 molar equivalent of the polymerization initiator. 10. The method of claim 9,
The trifunctional silane coupling agent may be selected from the group consisting of trichloro (methyl) silane, trichloro (ethyl) silane, trichloro (propyl) silane, trichloro (butyl) silane, trichloro (decyl) silane, trichloro (cyclohexyl) silane , Trichloro (phenyl) silane, trichloro-3-chloropropyl silane, trichloro (trifluoromethyl) silane, trichloro (trifluoroethyl) silane, trichloro (trifluoropropyl) silane, trichloro (1H, 1H, 1H, 2H, 2H-tridecafluoro-n-octyl) silane and trichloro Gt; asphalt modifier. ≪ / RTI > In an asphalt composition comprising asphalt, a cross-linking agent and an asphalt modifier,
Wherein the asphalt modifier is an asphalt modifier according to any one of claims 1 to 8.