JP3503255B2 - Block copolymer and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel block copolymer and a method for producing the same. The block copolymer produced according to the present invention has an extremely high molecular weight region, which is not found in conventional block copolymers, and when used as an asphalt modifier, has a large elongation, excellent toughness, tenacity and the like. It is a copolymer suitable for road pavement, roofing, waterproof sheet, and the like. It is also useful for resin modification, footwear, and other industrial applications.

[0002]

2. Description of the Related Art In recent years, branched block copolymers composed of various vinyl aromatic compounds and conjugated diene compounds have been proposed, but these block copolymers have a limited molecular weight distribution and their performance. Was not always satisfactory. For example, in Japanese Patent Publication No. 40-24915, Japanese Patent Publication No. 49-34478, etc.
Branched polymers, and multibranched copolymers have been introduced in JP-A-54-11191 and JP-B-3-40047, and these branched copolymers are used as rubber for asphalt modification. In this case, although the softening point improving effect was recognized, there was a problem that the low temperature elongation, toughness, and tenacity improving effects were insufficient. Further, when such a conventional block copolymer is blended with asphalt,
There are also problems that the melt viscosity is too high and that phase separation easily occurs during storage.

[0003]

A good balance between a large elongation and a softening point which cannot be achieved when used as
Another object of the present invention is to provide a block copolymer having extremely excellent mechanical strength improvement properties such as toughness and tenacity, and a method for producing the block copolymer.

[0004]

Means for Solving the Problems The present inventors have made the following problems regarding the above problems, that is, improvement in low temperature elongation and other mechanical properties desired when a branched block copolymer is used as an asphalt modifier. According to the invention, such a conventional branched block copolymer and a rubber for asphalt modification have been intensively studied, and as a result, the block copolymer having a high molecular weight region due to the multi-stage branched structure of the present invention is remarkably used as a rubber for asphalt modification. They have a large elongation, toughness, and tenacity, and have found that they are extremely excellent, and have completed the present invention.

Namely, the present invention is an inert organic solvent, under
Paragraphs (0007) to (0009) or paragraph (001)
0) to (0012), the first or a reaction,
2 or b reaction and 3rd step or c reaction
Or after performing the first to third stages or I to C reaction.
The second stage or b and / or the third stage or c
After repeating the same reaction as above, the polyfunctional coupling
After coupling with
And at least once before the coupling reaction
A block copolymer comprising 10% by weight to 60% by weight of a vinyl aromatic compound and 90% by weight to 40% by weight of a diene compound, wherein (a ) a glass transition of a viscoelasticity spectrometer (hereinafter abbreviated as VES). It has two or more points Tg, the high temperature side Tg is 50 ° C. or higher, and the low temperature side Tg is 10
And (b) a gel permeation chromatograph (hereinafter abbreviated as GPC) differential refractometer (hereinafter RI
The weight average molecular weight (Mw) in terms of standard polystyrene is 80,000 to 500,000, and the ratio Mw / Mn to the number average molecular weight (Mn) is 1.45.
4.50, and (c) below the molecular weight of the minimum molecular weight peak (M
abbreviated as wL) is 30,000 to 200,000,
(D) 40% by weight or less of a low molecular weight portion having a molecular weight of less than 30,000, (e) the following formula (1) measured by GPC-low angle light scattering device (hereinafter abbreviated as LALLS) and RI.

[0006]

[Formula 3] (In the formula (1), aLMwL5 to 15 are the LALLS to the total LALLS area in the region of 5 to 15 times the molecular weight MwL of the peak of the minimum molecular weight among the peaks of molecular weight 30,000 or more measured by RI. It represents the area ratio of the high molecular weight part, and aRMwL5 to 15 are 5 of RI MwL.
HR is represented by the ratio of the area of the high molecular weight part of RI to the total RI area of the molecular weight region of 1 to 15 times).
A block copolymer of 0 to 20.0, and for producing the same,

A method for producing a block copolymer, which comprises performing the following first, second and third stage reactions in an inert organic solvent and then coupling with a polyfunctional coupling agent, One-step reaction) Polyvinyl aromatic compound or a monomer obtained by mixing one or more kinds of a diene compound and a monovinyl aromatic compound with a polyvinyl aromatic compound 0.02% by weight to 1
0.0 wt% (based on all monomers to be finally reacted) is reacted with a monoorganolithium compound having a molar ratio of the polyvinylaromatic compound and the monoorganolithium compound of 0.03 to 2.0. A polyfunctional polymerization initiator is produced.

(Second stage reaction) Monomer 10 wt% to 50 wt% consisting of 80 wt% to 100 wt% of monovinyl aromatic compound and 20 wt% to 0 wt% of diene compound for forming polymer block A Polymer block A is prepared by polymerizing the weight% (on the basis of all monomers to be finally reacted) in the presence of the polyfunctional polymerization initiator obtained by the first stage reaction.

(Third stage reaction) 90% to 50% by weight of a monomer comprising 50% by weight to 100% by weight of a diene compound and 50% by weight to 0% by weight of a monovinyl aromatic compound for forming a polymer block B. % By weight (finally based on total monomers reacted) is added to the polymer obtained by the second stage reaction and polymerized to form a polymer block B to produce a block copolymer.

And, the production of a block copolymer characterized by carrying out the following reactions (a ), (b) and ( c ) in an inert organic solvent, followed by coupling with a polyfunctional coupling agent. Method ( a ) Reaction Monomer for forming polymer block A Monovinyl aromatic compound 80 wt% to 100 wt% and diene compound 20 wt% to 0 wt% Monomer 10 wt% to 50 wt%
A polymer block A is produced by using (on the basis of all finally reacted monomers) a monoorganolithium compound as an initiator.

[0011] In (b reaction) polyvinyl aromatic compound 0.02 wt% to 10.0 wt% molar ratio relative to mono-organolithium compound was used in Lee reaction (total monomers criteria for final reaction) 0 .03-2.
In addition to the polymer Lee reacted as in becomes 0 reacted.

( C Reaction) Diene compound 50 for forming polymer block B
90% to 50% by weight of a monomer consisting of 50% to 100% by weight and 50% to 0% by weight of a monovinyl aromatic compound
(Total monomer basis for final reaction) was added to the polymer obtained by the B reaction to produce the block copolymer to form a polymerized to polymer block B. Is provided.

The block copolymer of the present invention and the method for producing the same will be described below in detail. The block copolymer of the present invention has a bound vinyl aromatic compound amount of 10% by weight to 60% by weight, preferably 10% by weight to 50% by weight. When the binding amount of the vinyl aromatic compound is less than 10% by weight, the tensile strength of the block copolymer is lowered, and when it is used as a rubber for asphalt modification, the effect of improving the softening point of the asphalt compound becomes small, which is preferable. Absent. On the other hand, when the content of the bound vinyl aromatic compound is more than 60% by weight, the elongation of the asphalt compound is lowered, which is not preferable.

The block copolymer of the present invention has a plurality of Tg's measured by VES, at least its high temperature side Tg is 50 ° C. or higher, particularly preferably 60 ° C. or higher, and its low temperature side Tg. Is 10 ° C. or lower, preferably 0
It is below ℃. It may also contain a block copolymer having another Tg portion between them. When the high temperature side Tg is lower than 50 ° C. or the low temperature side Tg is higher than 10 ° C., the tensile strength is lowered. The block portion showing such Tg is composed of a polymer block of vinyl aromatic compound and a polymer block of diene compound, or one of the polymer blocks is a copolymer, or each polymer block is It is such that it consists of composition ratios of different vinyl aromatic compounds.

When the block portion having a Tg of 50 ° C. or higher (hereinafter referred to as polymer block A) is a vinyl aromatic compound block, the amount of the vinyl aromatic compound block is preferably 10% by weight to 45% by weight. If it is less than 10% by weight, the strength and the softening point of the asphalt compound are lowered, and if it is more than 45% by weight, the elongation of the asphalt is lowered, which is not preferable. Further, the polymer block A
Is a copolymer of a vinyl aromatic compound and a diene compound, the block of the vinyl aromatic compound alone is 0% by weight.
It may be up to 45% by weight.

The preferred range of the molecular weight of the polymer block A is 10,000 to 50,000. When the molecular weight is less than 10,000, the strength and the softening point of the asphalt compound are lowered, and When it is more than 50,000, the moldability is deteriorated and the asphalt elongation is lowered, which is not preferable.

It is preferable that the polymer block having a VES Tg of 10 ° C. or lower is a block of a copolymer of a vinyl aromatic compound and a diene compound, which has a higher randomness. When the randomness is poor, it is difficult to reproduce the physical properties.

The vinyl bond content of the diene moiety of the copolymer of the present invention is not particularly limited, but it is desirable to be less than 50% by weight, preferably 40% by weight or less of the bound diene. If there are too many vinyl bonds, the heat resistance will deteriorate, which is not preferable.

The block copolymer of the present invention has a GPC molecular weight distribution different from that of a conventional block copolymer and has a continuous polymodal structure having an ultrahigh molecular weight portion.
The weight average molecular weight Mw in terms of standard polystyrene measured by GPC-RI is 80,000 to 500,000, preferably 100,000 to 400,000, and Mw / M.
n is 1.45 to 4.50.

When the Mw is less than 80,000, the tensile strength is lowered and the softening point, toughness and tenacity of the asphalt compound are lowered. Mw is 500,00
When it is more than 0, the block copolymer is unfavorable in terms of finishability and moldability and deterioration of solubility in asphalt. If the Mw / Mn is less than 1.45, the elongation of the asphalt compound will be small and the Mw
When / Mn is larger than 4.50, the tensile strength of the block copolymer is lowered, which is not preferable.

The block copolymer of the present invention is a block copolymer which is coupled with a coupling agent, and the block copolymer before coupling is GPC-R.
It is measured by I as the minimum molecular weight peak among the peaks of molecular weight 30,000 to 200,000. The molecular weight MwL of the peak of this minimum molecular weight portion is 30,000 to 200,
000, preferably 40,000 to 180,000, and the minimum molecular weight peak (uncoupled portion) is desirably 90% by weight or less.

If the peak MwL is less than 30,000 or the amount of uncoupling is more than 90% by weight, the tensile strength of the block copolymer is lowered, and if the peak MwL is more than 200,000, the asphalt is not formed. Solubility deteriorates. In the case where the distribution spreads toward the lower molecular weight side than the molecular weight of 30,000 or has a peak, the low molecular weight portion of the lower molecular weight of 30,000 is 40% by weight or less, preferably 20% by weight or less. 40
If it exceeds 5% by weight, the tensile strength and the like of the obtained block copolymer are significantly lowered, which is not preferable.

The block copolymer of the present invention is also characterized by a high molecular weight region measured by GPC-LALLS at the same time as GPC-RI which is usually measured. That is, the high molecular weight ratio (HR) calculated by the following formula (1) is

[0024]

[Formula 4] (In the formula (1), aLMwL5 to 15 are the LALLS to the total LALLS area in the region of 5 to 15 times the molecular weight MwL of the peak of the minimum molecular weight among the peaks of molecular weight 30,000 or more measured by RI. It represents the area ratio of the high molecular weight part, and aRMwL5 to 15 are 5 of RI MwL.
The ratio of the area of the high molecular weight part of RI to the total RI area of the molecular weight region of 1 to 15 times is 1.0 to 20.0, preferably 1.5 to 20.0, and particularly preferably 2.0 to 1.
It is 8.0. When the high molecular weight ratio HR is less than 1.0, the effect of improving elongation is small even if asphalt is blended, which is not preferable. On the other hand, if the HR is 20.0 or more, the solubility in asphalt or the like is deteriorated and the moldability is deteriorated, which is not preferable.

There are roughly two methods for producing the block copolymer of the present invention having the above-mentioned ultra-high molecular weight region. One method is to prepare a polyfunctional polymerization initiator with a monoorganolithium compound and a polyvinylaromatic compound in the first step reaction, and then use a polymer block A (monovinylaromatic compound is 80% by weight or more) and a polymer block. A block copolymer comprising a repeating unit of B (50% by weight or more of a diene compound) is produced and coupled with a polyfunctional coupling agent. Another method is the first step. In the reaction, using a monoorganolithium compound as an initiator,
It is a production method in which the polymer block A or B is formed, the polyvinyl aromatic compound is reacted once or more during the second-stage reaction to the final-stage reaction, and finally coupled.

The method for producing the block copolymer of the present invention by reacting a polyvinyl aromatic compound in the first stage reaction of the multistage reaction is, for example, propane, butane, n-pentane, cyclopentane, n-hexane, cyclohexane, A small amount of polar compounds such as ethers and tertiary amines tetrahydrofuran, α-methoxymethyltetrahydrofuran, α-methyltetrahydrofuran, triethylamine, in an inert organic solvent such as benzene or toluene mixed with one or more kinds. N, N, N ', N'-tetramethylpropanediamine, N, N, N', N'-tetramethylethylenediamine, N, N, N ', N'-tetraethylethylenediamine, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, etc. Alcohol Arco LAT, eg potassium-ter
It is produced in the presence or absence of one or more t-butyl alcoholate, potassium-tert-amyl alcoholate and the like.

The amount of the polar compound acting as the vinylating agent or the randomizing agent as described above is 10 parts by weight or less with respect to 100 parts by weight of the monomer used, and the addition amount depends on the purpose and effect. It is determined.

A monoorganolithium compound and a polyvinylaromatic compound, or a monoorganolithium compound and a polyvinylaromatic compound and a diene compound, or a monoorganolithium in the above solvent in the presence or absence of a polar compound. A first stage polymerization reaction is carried out using a compound, a polyvinyl aromatic compound and a monovinyl aromatic compound, or a monoorganolithium compound, a polyvinyl aromatic compound, a monovinyl aromatic compound and a diene compound.

The amount of the monomers used in these first-stage reactions is 0.02% by weight to the total amount of the monomers finally reacted.
It is 10.0% by weight, preferably 0.05% by weight to
5.0% by weight, particularly preferably 0.05% by weight to 2.0
% By weight. When the amount of the monomer in the first stage reaction is less than 0.02% by weight, the effect of increasing the molecular weight of the finally obtained block copolymer becomes small, and the effect of improving elongation when used in asphalt becomes small. On the other hand, if it exceeds 10% by weight, when the first-stage reaction product is produced in a large amount and used as a polyfunctional polymerization initiator, the viscosity becomes large and the operation is deteriorated, which is not preferable.

Examples of the monoorganolithium compound used in the reaction of the present invention include n-propyllithium, isopropyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, methyllithium and n-decyllithium. , Phenyllithium, naphthyllithium and the like, and examples of the polyvinyl aromatic compound include divinylbenzene, 1,2,4-trivinylbenzene, 1,3-divinylnaphthalene, 1,8-
Divinylnaphthalene, 1,3,5-trivinylnaphthalene, 2,4-divinylbiphenyl, 3,5,4'-trivinylbiphenyl, diisopropenylbenzene, 3,
There are 4,5,6-tetramethyl-1,2-diisopropenylbenzene and the like, and particularly preferable compounds include m-divinylbenzene and p-divinylbenzene.

The diene compound is, for example,
1,3-butadiene, isoprene, 2,3-dimethyl-
1,3-butadiene, 1,4-pentadiene, piperylene, 3-butyl-1,3-octadiene, phenyl-
There are 1,3-butadiene and the like, and among them, 1,3-butadiene is preferable. Examples of the monovinyl aromatic compound used in the present invention include styrene, p-methylstyrene, tertiary butylstyrene, α-methylstyrene, 1,
Examples thereof include monomers such as 1-diphenylethane, and among them, styrene is preferable.

The above various monoorganolithium compounds, polyvinylaromatic compounds, diene compounds, and monovinylaromatic compounds may be used alone or in admixture of two or more. The addition and reaction order of these is not particularly limited, and the monoorganolithium compound is added to the solvent, and then each monomer is added separately to react, or the mixed monomers are added to react. Alternatively, a method in which the mixed monomers are first added to the solvent and then the monoorganolithium compound is added and the mixture is reacted can be used.

The monoorganolithium compound used in the present invention is 0.005 to 0.060 parts by weight, preferably 0.010 parts by weight, based on 100 parts by weight of all the monomers used in each stage. It is from 0.05 to 45 parts by weight. The amount to be used is determined depending on the desired molecular weight of the finally obtained block copolymer, the solvent, the degree of purification of the monomers, and the like.

The polyvinyl aromatic compound is in the range of 0.03 mol to 2.0 mol per mol of the monoorganolithium compound, and the addition amount of the monovinyl aromatic compound or the diene compound is the viscosity of the first-stage polymer to be produced. It is within the range where the increase is not remarkable, and is preferably within 50 times (molar ratio) of the monoorganolithium compound.

The reaction is carried out at a temperature of 0 ° C. with stirring under a nitrogen atmosphere.
It is carried out at a constant temperature or an elevated temperature in the range of 120 ° C. Thereafter, when the second-stage reaction is continuously carried out and the first-stage reaction product is produced in a large amount and used as a polyfunctional polymerization initiator after the second-stage reaction, the first-stage reaction is completed. A small amount of the post-diene compound can be added.

The second-step reaction is carried out by adding the second-step monomer to the first-step reaction product produced as described above.
Alternatively, the first-stage reaction product prepared as a polyfunctional polymerization initiator is added to a separately prepared solvent and the second-stage monomer to carry out. In the latter case, it is possible to produce a large amount of the reaction product of the first stage reaction, and the reaction product is West German Patent 20033.
It is a polyfunctional polymerization initiator as described in Japanese Patent No. 84 and Japanese Patent Publication No. 43-25510.

The second step reaction is the monovinyl aromatic compound 80.
% By weight to 100% by weight and diene compound 20% by weight to 0
It may be added separately or as a mixture. In this way, the VES ta
Polymer block A having nδTg of 50 ° C or higher is polymerized. After the completion of the second-step reaction, the monomer of the third-step reaction is added to continue the polymerization.

The monomer for the third stage reaction is a diene compound 50.
Wt% to 100 wt%, preferably 60 wt% to 100
% By weight and 50% to 0% by weight of monovinyl aromatic compound, preferably 40% to 0% by weight. If more randomness is desired, a randomization method using the polar compound, a randomization method using an additional addition method of a diene compound by the method described in JP-B-3-44089, or the like is used. To be done.

By the above-mentioned third step reaction, t of VES
forming a polymer block B having an δTg of 10 ° C. or lower,
A block copolymer is obtained. Alternatively, the polymer block A can be formed again by repeating the second step reaction. Alternatively, after the first-stage reaction, the third-stage reaction is carried out first, and then the second-stage reaction is carried out to obtain a block copolymer in which B is formed and then A is formed, or the polymer is then obtained. There are also a method of forming block B and a method of repeating the reaction to obtain a multistage block copolymer.

The block copolymer of the present invention basically comprises
Polymer block A with tan δTg of VES of 50 ° C or higher
And Tg are polymer blocks B having a Tg of 10 ° C. or less, but a structure having a polymer block having a different Tg may be used. The polymer block A is preferably 10% by weight to 50% by weight in the finally obtained block copolymer.

If the amount of the polymer block A is less than 10% by weight, the tensile strength of the resulting block copolymer is lowered, and the softening point is lowered in the asphalt compound, which is not preferable. On the other hand, if it is more than 50% by weight, the elongation at the time of compounding with asphalt becomes small, which is not preferable. Further, when the block copolymer has two or more polymer blocks A and polymer blocks B in the block copolymer before coupling having a three-stage structure, a four-stage structure, etc., each of them has a different size or Alternatively, the amount of bound vinyl aromatic may be used.

Next, another method for producing the block copolymer of the present invention will be described. The method in an inert organic solvent, a mono-organolithium compound monovinyl aromatic compound as a polymerization initiator, or monovinyl aromatic compound and a polymer block A of Lee reactions consisting of diene compound is polymerized form, as subsequently b reaction It reacted by adding an amount of 0.03 to 2.0 times in a molar ratio of the polyvinyl aromatic compound relative to the active lithium amount in (a) the reaction polymer. Incidentally, the B reaction monovinyl aromatic compound and a diene compound by adding an appropriate amount At a, may be reacted. Subsequently, the monomer forming the polymer block B of the reaction C is added and reacted. The randomization method of the polymer block B is performed in the same manner as the randomization method of the polymer B.

By the manufacturing method as described above, basically A
Block having a structure of forming B and then forming B, or a structure of forming polymer block B first and then forming polymer block A by a reaction of C , basically forming B and then forming A Make it a copolymer. Other, either to form a subsequent repetition polymer block A or polymer block B, and b reaction by a multistage reaction in which reaction at least once in the final reaction from Ha reaction, it is possible to produce a block copolymer. Solvent of the present production method, monoorganolithium and its amount, polyvinyl aromatic compound, polymer block A
The polymer block B is basically the same as the above-mentioned manufacturing method.

The preferred polymerization temperature of the block copolymer of the present invention is 0 ° C to 120 ° C, particularly preferably 20 ° C to
The temperature is 110 ° C., and either polymerization at a constant temperature or polymerization at an elevated temperature may be performed. The polymerization method is not particularly limited, such as continuous polymerization and batch polymerization. The block copolymer of the present invention is
It is obtained by further coupling the block copolymer having active lithium at the terminal of the polymer produced as described above with a polyfunctional coupling agent to obtain a block copolymer having an ultrahigh molecular weight part.

The polyfunctional coupling agent used in the present invention has a functionality of two or more. Examples of such a polyfunctional coupling agent include JP-A-3-281515 and JP-A-3-287617. , The multi-vinyl aromatic compound, the multi-epoxide, the multi-isocyanate, the multi-imine, the multi-aldehyde, the multi-ketone, the multi-halide, the multi-acid anhydride, the carboxylic acid esters and the like of JP-B-58-39444. Examples of the multi-vinyl aromatic compound include those used as the polyvinyl aromatic compound of the present application, and examples of the diepoxy compound include bisphenol A diglycidyl ether and bisphenol F diglycidyl ether, and other multiepoxides. Are epoxidized soybean oil, epoxidized linseed oil, epoxidized polybutadiene and the like.

Examples of multiisocyanates include benzene-1,2,4-triisocyanate, naphthalene-1,2,5,7-tetraisocyanate, polyarylpolyisocyanate and the like.

Examples of multiimines are tri (1-aziridinyl) phosphine oxide, tri (2-methyl-1).
-Aziridinyl) phosphine oxide, etc., and the multialdehyde is, for example, 1,4,7-naphthalene tricarboxaldehyde, 1,7,9-anthracentricarboxaldehyde, etc., and the multiketone is, for example, 1,4,9. , 10-anthracene tetron and the like, and pyromellitic dianhydride as an example of the multi-acid anhydride,
Examples thereof include styrene-maleic anhydride copolymer, and examples of multiesters include dimethyl adipate, diethyl adipate, triethyl citrate, and 1,3,5-tricarbethoxybenzene.

The multi-halides include metal halogen compounds, organic metal halogen compounds and organic halogen compounds. Examples thereof include silicon tetrachloride, silicon tetrabromide, stannic chloride, trifluorosilane, trichlorosilane and trichloroethyl. Silane, tribromobenzylsilane, dichlorodimethylsilane, dichlorodiethylsilane, methyltrichlorotin, diphenyldibromotin, carbon tetrachloride, dichloromethane, trichloroethylene, dichloroethylene, dibromoethane, dichlorobenzene, dibromobutane, hexachloroethane, hexachlorodisilane and the like. Other than this, metal multialkoxides are also good examples, such as dimethoxysilane, diethoxysilane, trimethoxysilane, tetramethoxysilane,
Tetraethoxysilane and the like.

The above polyfunctional coupling agents may be used alone or as a mixture of two or more kinds. The amount of these used is 0.05 to 1.5 equivalents with respect to the block copolymer-bound active lithium,
It is preferably 0.05 equivalent to 1.0 equivalent. The coupling reaction time is about 0.5 minutes to 2 hours, and the temperature is 0.
Reacts in the range of ℃ ~ 120 ℃.

The block copolymers of the present invention include suitable stabilizers, for example phenolic, sulfur, or phosphorus anti-aging agents such as 2,6-di-tert-butyl-4-methylphenol and / or Add one or more kinds of light stabilizers, etc., and remove the solvent, such as hot water stripping, hot roll,
Finishing by a known method such as drum dryer drying, methanol precipitation drying, vacuum drying, etc., and an antiblocking agent and the like can be added if necessary. The block copolymer of the present invention thus obtained has an extremely high molecular weight portion, and is a copolymer useful for asphalt modification applications, footwear applications, resin modification applications, and other molded articles. Is.

[0051]

EXAMPLES The present invention will be described below with reference to examples.
These examples do not limit the invention. The structure analysis and physical property measurement of the copolymer were carried out according to the following methods. 1) Total styrene content : UV spectrophotometer (Hitachi UV 2
00) was used to calculate the absorption intensity at 262 nm. 2) Microstructure of butadiene block part : Measured using an infrared spectrophotometer (Model 1710 manufactured by Parking Elmer) and measured by the Hampton method.

3) peak molecular weight and high molecular weight ratio HR,
Low molecular weight part with a molecular weight of less than 30,000 : GPC [The device is manufactured by Waters, and the column is Z manufactured by DuPont.
Two ORBAX PSM 1000-S and PSM 6
There are three combinations of 0-S. Tetrahydrofuran is used as the solvent, and the measurement conditions are a temperature of 35 ° C. and a flow rate of 0.7 ml.
/ Min, sample concentration 0.1% by weight, injection volume 50 μl]
The peak molecular weight and the composition ratio were determined from the chromatogram of. The peak molecular weight is a converted value from the following standard polystyrene (manufactured by Waters) calibration curve. 1.75 × 10 ⁶ , 4.1 × 10 ⁵ , 1.12 × 1
0 ^5, 3.5 × 10 ^4, made 8.5 × 10 ³ GPC detector RI Showa Denko Shodex RI SE-61 LALLS CHROMATIX Corporation MODEL CMX-100

4) Measurement of glass transition point Tg : The temperature of the tan δ peak of a viscoelastic spectrometer is measured as Tg. VES-FIII type 5) manufactured by Iwamoto Seisakusho Co., Ltd. 5) Weight% and molecular weight of block polymer A : A block copolymer is sampled at each reaction stage during the polymerization reaction and determined from its solid content. When the block polymer A was a monovinyl aromatic compound block only, the block polymer B was cut off by the osmium acid decomposition method, and then the measurement was performed by the UV method of 1). The molecular weight was measured by GPC in 3).

Measurement of physical properties of asphalt composition 6) Toughness, tenacity : Measured according to the test method for paving work (edited by Japan Road Construction Industry Association). 7) Elongation and softening point : Measured according to JIS-K 2207.

Example 1 6.5 kg of cyclohexane and 1.3 m-divinylbenzene were placed in a 12 liter autoclave equipped with a stirrer and purged with nitrogen.
g, 1,3-butadiene 18 g were charged, the temperature was set to 60 ° C. with stirring, and 2.1 g of n-butyllithium was added to carry out the first-stage reaction. After reacting for 30 minutes at the same temperature, 250 g of styrene monomer in the second stage was added and polymerized. The temperature rose by 7 ° C. and the reaction was completed in 6 minutes. After this,
730 g of third stage 1,3-butadiene was added and polymerized. The temperature reached 82 ° C., and the reaction was completed in about 15 minutes. As a coupling agent, a mixture of 50% by weight of each of two compounds represented by the following general formula (hereinafter, abbreviated as X-1)
0.50 was added at an X-1 / lithium equivalent ratio and reacted for 10 minutes.

[0056]

[Chemical 1]

Example 2 Tetrahydrofuran 20 g was added to the solvent, diisopropenylbenzene 1.6 g and n-butyllithium 2.
The same procedure as in Example 1 was carried out except that the amount of styrene in the second stage was 200 g, the amount of the third stage monomer was 1,3-butadiene 730 g, and the amount of the styrene monomer was 50 g. The maximum temperature was 80 ° C.

Example 3 6.5 kg of cyclohexane and 20 g of tetrahydrofuran
And 290 g of styrene monomer were charged into a 12 liter autoclave, the temperature was raised to 66 ° C. with stirring, and n
-Butyllithium (2.5 g) was added to carry out a reaction polymerization. After 4 minutes, exit temperature is 74 ° C. becomes polymerization, m- divinylbenzene B anti <br/> response was reacted 1.2g added 10 minutes. Further, 650 g of 1,3-butadiene and 60 g of isoprene were added as monomers for the Ha reaction, and polymerization was carried out. After about 13 minutes, the temperature reached 84 ° C., and after the polymerization was completed, silicon tetrachloride was added in an amount such that the lithium equivalent ratio was 0.2, and the coupling reaction was carried out for 10 minutes.

[Preparation of First Stage Reaction Polyfunctional Polymerization Initiator]
Polyfunctional initiators C-1, C-2, prepared in the first stage reaction,
C-3 was produced in the following manner with the formulations shown in Table 1. The amount of dehydrated cyclohexane shown in Table 1 was added to a jacketed nitrogen-substituted 12-liter autoclave.
3-Butadiene and m-divinylbenzene were charged, the reaction start temperature was adjusted with vigorous stirring, and a predetermined amount of n-butyllithium was added and reacted. The reaction temperature was controlled by flowing warm water or cold water through the jacket. Regarding C-1, after the reaction was completed, 55 g of 1,3-butadiene was added and reacted for 10 minutes. After completion of each reaction, the mixture was cooled to room temperature and stored in a container.

[0060]

[Table 1]

[Production of Examples 4 to 21 and Comparative Examples 1 to 7]
6.5 kg of cyclohexane was charged into a nitrogen-substituted 12-liter autoclave equipped with a stirrer, and copolymers were produced according to the formulations shown in Tables 2, 3, and 4 as described below.

Example 4 After charging cyclohexane, 21 g of tetrahydrofuran was added, and 250 g of second-stage reacted styrene monomer was added. The temperature was adjusted to a polymerization initiation temperature of 73 ° C., and a polyfunctional polymerization initiator C-3 was added as a first-stage reaction product so that the amount was 1.8 g in terms of n-butyllithium to initiate polymerization.
After reaching the maximum polymerization temperature of styrene, the third stage styrene 10
0 g and 340 g of 1,3-butadiene were added to initiate the third stage polymerization. 5 minutes before reaching the maximum polymerization temperature 1,
300 g of 3-butadiene was continuously added over 10 minutes and polymerized. After completion of polymerization, bifunctional coupling agent X-
1 was added at an X-1 / lithium equivalent ratio of 0.50 and reacted for 10 minutes.

Examples 5, 6, 7, 8, 9, 10 Polymerization was carried out in the same manner as in Example 4 according to the formulation shown in Table 2. Example 5
Is a copolymer in which the polymer block B is a copolymer of butadiene and isoprene, and Example 6 has a three-stage structure and is a type in which the final polymer block A is coupled. Example 7 has a structure in which B is formed first and then A is formed, the polymer block B is made of butadiene, and the polymer block A is a copolymer of styrene and butadiene.

In Examples 8, 9 and 10, C-1 was used as the polyfunctional polymerization initiator of the first-stage reaction product. Example 7 uses N, N, N ', N'-tetramethylethylenediamine as the polar compound and the coupling agent is silicon tetrachloride. Example 9 has a three-stage structure in which B is formed first,
The block B and the polymer block A of the butadiene polymer are polystyrene, and the final polymer block B is butadiene and is coupled with silicon tetrachloride.

Examples 11 to 18 Polyfunctional polymerization initiator C-2 was used in the formulation shown in Table 3,
Polymerization was carried out according to Example 4. Examples 11, 12, 1
3 and 14 each have a structure in which A is formed and then B is formed. The polymer block A is polystyrene, or the polymer block A of Example 13 is styrene and butadiene.
And the polymer block B is a styrene-butadiene copolymer or polybutadiene.

Example 15 has a structure in which B is formed first, and then A is formed. 690 g of 1,3-butadiene is polymerized and then 300 g of styrene is polymerized, and silicon tetrachloride is added at a lithium equivalent ratio of 0.60. Then, it was reacted for 10 minutes. Examples 16 and 17 have a three-stage structure, and Example 18 has a three-stage structure in which B is formed previously.

Example 19 6.5 kg of cyclohexane and 19 g of tetrahydrofuran
After charging 150 g of styrene monomer with an autoclave and heating to 65 ° C., n-butyllithium was added to 3.
5g was added and the reaction of b was carried out. After the temperature reached 70 ° C in 5 minutes and the polymerization was completed, 800 g of 1,3-butadiene which had been previously reacted with Ha
And 50 g of styrene monomer were added and polymerized. afterwards
(B) 3.9 g of m-divinylbenzene of the reaction was added and reacted. When a part of this block copolymer was taken out and measured by GPC, HR was 0.75. Then, 0.5 was added to the block copolymer in the autoclave at an equivalent ratio to lithium of 0.5, and the coupling reaction was carried out for 10 minutes. The analytical values and the physical property values are shown in Tables 5 and 6, respectively.

Example 20 6.5 kg of cyclohexane, 4 g of tetrahydrofuran and 150 g of 1,3-butadiene were charged into an autoclave, and 3.0 g of n-butyllithium was added at 71 ° C.
A step reaction occurred. Thereafter, 250 g of styrene monomer was added to carry out the second stage reaction, and further, 1.6 g of diisoprenepropenylbenzene was added and reacted as the third stage reaction.
As a fourth stage reaction, 20 g of styrene monomer and 580 g of 1,3-butadiene were mixed and added and polymerized. Finally, 0.3 is added to X-1 in an equivalent ratio to lithium, and 10 is added.
Reacted for minutes.

Example 21, Comparative Example 7 6.5 kg of cyclohexane and 200 g of styrene monomer were charged into an autoclave, and 2.7 g of n-butyllithium was added at 70 ° C. to carry out the first stage polymerization. Continue 1,3
-Butadiene 300g and styrene monomer 100g were mixed and added to start the reaction. After 3 minutes from the start of the reaction in the second stage, 400 g of 1,3-butadiene was continuously added for 30 minutes to react. After the reaction was completed, 1.3 g of m-divinylbenzene was added to carry out a third stage reaction. After the completion of the 3rd stage reaction, 1/2 amount of the polymer in the autoclave was withdrawn to obtain the uncoupled block copolymer of Comparative Example 7. The coupling agent trimethoxysilane was added to the residual block copolymer in the autoclave in an amount of 0.3 equivalent to the residual lithium, and the mixture was reacted for about 15 minutes to obtain the block copolymer of Example 21.

Comparative Examples 1, 2, 3, 4, 5, 6 Production of Block Copolymer Polymerization was carried out according to the formulation of Table 4 and in accordance with Example 1.
Comparative Examples 1 and 2 are examples in which no polyvinyl aromatic compound is used, and as shown in Table 7, the HR is small and the high molecular weight ratio is low. In Comparative Examples 3 and 6, the first-stage reaction product was a polyfunctional initiator C-
In Comparative Example 3, the amount of low-molecular-weight part having a molecular weight of 30,000 or less was excessive, and in Comparative Example 6, a significantly high HR was obtained, but some gelation was observed and moldability was poor. The tensile test could not be done.

In Comparative Examples 4 and 5, the polyfunctional initiator C-2 was used in the first-stage reaction product, but in Comparative Example 4, HR was 0 without coupling, and in Comparative Example 5, polymer block A was used. Is a low Tg block copolymer without the presence of

The copolymers of Examples and Comparative Examples obtained as described above were mixed with a small amount of water, and then 2,6-di-ter was added as a stabilizer per 100 parts by weight of the copolymer.
0.8 parts by weight of t-butyl-4-methylphenol and 0.5 parts by weight of tris (nonylphenyl) phosphite were added as stabilizers, and the solvent was removed with a 120 ° C. hot roll to obtain a block copolymer. The analytical values of the block copolymer thus obtained are shown in Tables 5, 6 and 7. The block copolymer of the present invention exhibits high HR.

[Evaluation of Asphalt Mixing of Block Copolymer] 6.0 g each of the block copolymers of Examples 1 to 21 and the block copolymers of Comparative Examples 1 to 7 and straight asphalt [manufactured by Nippon Oil Co., Ltd.] , Stores 60/80]
100 g of each was melt-kneaded at 180 ° C. for 90 minutes to prepare an asphalt compound. In Comparative Example 6, the solubility in asphalt was remarkably inferior, and undissolved matter remained, so the physical property test was not conducted. The results of measuring the physical properties of these asphalt compounds are shown in Tables 8, 9 and 10.

The softening points of the asphalt blends prepared by the multi-stage polymerization of the present invention and the block copolymers of Examples 1 to 21 having an ultrahigh molecular weight region, which were coupled with a polyfunctional coupling agent, were compared. Almost the same as the example, but 7
Both softening point and
Excellent elongation balance. The toughness-tenacity is also large. In Comparative Example-5, the elongation at 15 ° C is excellent, but the softening point is extremely low and the balance is poor. It can be seen that the block copolymer of the present invention has excellent performance when used as a rubber for asphalt modification.

[0075]

[Table 2]

[0076]

[Table 3]

[0077]

[Table 4]

[0078]

[Table 5]

[0079]

[Table 6]

[0080]

[Table 7]

[0081]

[Table 8]

[0082]

[Table 9]

[0083]

[Table 10]

[0084]

EFFECT OF THE INVENTION It has a unique molecular weight distribution structure different from that of the conventional block copolymer, and in particular, has excellent performance as a rubber for modified asphalt. The asphalt composition has a high elongation and a good balance with the softening point. In addition, high toughness and tenacity can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of GPC molecular weight distribution of the copolymer of the present invention, in which the same sample is simultaneously subjected to R with the same GPC.
I and LALLS were measured and the molecular weight at that time was 30,000
The minimum molecular weight peak MwL among the peaks of 0 or more and the area area of 5 to 15 times the molecular weight (LAL)
LS area is aLMwL5-15, RI area is aRMwL
5 to 15) and a portion having a molecular weight of less than 30,000.

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-3-74421 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08F 297/04 C08F 8/42

Claims (15)

(57) [Claims] 1. An inert organic solvent comprising the following first, second and
After performing the third stage reaction, or after performing the first to third stage reactions
Furthermore, the same reaction as the reaction of the second stage and / or the third stage
After repeating, coupling with polyfunctional coupling agent
10% by weight to 6 of a vinyl aromatic compound obtained by
A block copolymer consisting of 0% by weight and 90% by weight to 40% by weight of a diene compound, which comprises (a) two or more glass transition points (Tg) of a viscoelasticity spectrometer (VES) at a high temperature. Side Tg is 50 ° C
Above, and Tg of the low temperature side is 10 degrees C or less, (b) Gel permeation chromatograph (GPC)
The weight average molecular weight (Mw) in terms of standard polystyrene measured by a differential refractometer (RI) is 80,000 to 500,0.
And the ratio Mw / Mn to the number average molecular weight (Mn) is 1.45 to 4.50, and (c) the molecular weight ( MwL ) of the minimum molecular weight peak among the peaks of GPC having a molecular weight of 30,000 or more. ) Is 30,000
˜200,000, (d) 40 wt% or less of the low molecular weight portion having a molecular weight of less than 30,000, (e) GPC-Low Angle Light Scattering Device (LALLS) and RI
The following formula (1) measured by (In the formula (1), aLMwL5 to 15 are the LALLS to the total LALLS area in the region of 5 to 15 times the molecular weight MwL of the peak of the minimum molecular weight among the peaks of molecular weight 30,000 or more measured by RI. It represents the area ratio of the high molecular weight part, and aRMwL5 to 15 are 5 of RI MwL.
HR is represented by the ratio of the area of the high molecular weight part of RI to the total RI area of the molecular weight region of 1 to 15 times).
A block copolymer of 0 to 20.0. (First stage reaction) polyvinyl aromatic compound or polyvinyl aromatic compound
One or more of diene compounds and monovinyl aromatic compounds
0.02% to 10.0% by weight of the mixed monomer (maximum
The polyvinyl aromatization based on all monomers that finally react)
The compound and the monoorganolithium compound have a molar ratio of 0.03 to
Multipurpose by reacting with a monoorganolithium compound of 2.0
A functional polymerization initiator is manufactured. (Second Stage Reaction) Monovinyl Aromatization for Forming Polymer Block A
80% to 100% by weight of compound and 20 weight of diene compound
% Monomer to 0% by weight 10% to 50% by weight
(Final reaction based on all monomers)
Polymerization in the presence of polyfunctional polymerization initiator obtained by
The body block A is manufactured. (Third Stage Reaction) Diene Compound 50 for Forming Polymer Block B
% To 100% by weight and 50 weight of monovinyl aromatic compound
90% to 50% by weight of monomer consisting of 0% to 0% by weight
(Final reaction based on all monomers)
Polymer block B is obtained by adding to the obtained polymer and polymerizing.
To form a block copolymer. 2. The bound vinyl aromatic compound is 10% by weight to.
60% by weight and 10 vinyl aromatic compound blocks
The polystyrene standard molecular weight of the block is 10,000 to 50,000 at a weight percentage of 45 to 45 wt%.
The block copolymer described. 3. A method for producing a block copolymer, which comprises performing the following first, second and third stage reactions in an inert organic solvent and then coupling with a polyfunctional coupling agent. (First stage reaction) 0.02 wt% to 10.0 wt% of a polyvinyl aromatic compound or a monomer obtained by mixing one or more kinds of a diene compound and a monovinyl aromatic compound with a polyvinyl aromatic compound (final reaction (Based on all monomers), the molar ratio of the polyvinyl aromatic compound to the monoorganolithium compound is 0.03 to
A polyfunctional polymerization initiator is produced by reacting with a monoorganolithium compound of 2.0. (Second Step Reaction) Monomer 10 wt% to 50 wt% composed of 80 wt% to 100 wt% of monovinyl aromatic compound and 20 wt% to 0 wt% of diene compound for forming the polymer block A
Polymer block A is produced by polymerizing (on the basis of all monomers to be finally reacted) in the presence of the polyfunctional polymerization initiator obtained by the first step reaction. (Third Stage Reaction) Diene Compound 50 for Forming Polymer Block B
90% to 50% by weight of a monomer consisting of 50% to 100% by weight and 50% to 0% by weight of a monovinyl aromatic compound
Polymer block B is prepared by adding (finally reacting all monomers) to the polymer obtained by the second stage reaction and polymerizing.
To form a block copolymer. 4. A process according to claim 3, wherein the performing the first to third stage reaction in the presence of a polar compound. 5. The production method according to claim 3, wherein the first-step reaction to the final coupling reaction are continuously performed. 6. The polymer block A is formed after the polymer block B is formed by exchanging the monomers used in the second step reaction and the third step reaction with each other. 6. The manufacturing method according to any one of to 5. 7. The same reaction as the reaction of the second and / or third step after repeating the first to third step reactions,
The method according to any one of claims 3 to 6, wherein a block copolymer is produced and then coupled. 8. The following reaction (a) and reaction (b ) in an inert organic solvent :
And after performing the Ha reaction, the cap is treated with a polyfunctional coupling agent.
Block copolymer obtained by pulling
After performing the reaction to the reaction, the reaction and / or the reaction is further performed.
After repeating the same reaction as above, polyfunctional coupling
Block copolymer obtained by coupling with an agent
Of the coupling reaction
A vinyl aromatic compound obtained at least once before
10% to 60% by weight and diene compound 90% by weight
A block copolymer consisting of 40% by weight, comprising: (a) a glass transfer of a viscoelasticity spectrometer (VES).
It has two or more transition points (Tg) and its high temperature side Tg is 50 ° C.
Above, and Tg of the low temperature side is 10 degrees C or less, (b) Gel permeation chromatograph (GPC)
Standard polystyrene conversion measured with a differential refractometer (RI)
Having a weight average molecular weight (Mw) of 80,000 to 500,0
00, the ratio Mw / Mn with the number average molecular weight (Mn) is
1.45 to 4.50, and (c) in the peak of GPC having a molecular weight of 30,000 or more.
The minimum molecular weight peak molecular weight (MwL) is 30,000
Is about 200,000, and (d) the low molecular weight portion having a molecular weight of less than 30,000 is
40% by weight or less, (e) GPC-low angle light scattering device (LALLS) and RI
In the following formula to measure (1) [number 2] (In Formula (1), aLMwL5 to 15 are measured by RI.
The minimum molecular weight peak in the peak above 30,000.
Total molecular weight range of 5 to 15 times the molecular weight MwL
Area of high molecular weight part of LALLS relative to LALLS area
ARMwL5 to 15 is 5 of RI MwL.
RI to the total RI area in the molecular weight range of 15 to 15 times
HR represented by (representing the area ratio of the molecular weight part) is 1.
A block copolymer of 0 to 20.0. ( A reaction) Monovinyl aromatization for forming polymer block A
80% to 100% by weight of compound and 20 weight of diene compound
% Monomer to 0% by weight 10% to 50% by weight
(On the basis of all monomers to be finally reacted) monoorganolithium
A polymer block A is produced by polymerizing a compound as an initiator.
It (B reaction) Polyvinyl aromatic compound 0.02% to 10.0% by weight
% (On the basis of all monomers to be finally reacted) was used in the reaction
The molar ratio to the monoorganolithium compound is 0.03 to
Add to the reaction polymer to make it 2.0
It (C reaction) Diene compound 50 for forming polymer block B
% To 100% by weight and 50 weight of monovinyl aromatic compound
90% to 50% by weight of monomer consisting of 0% to 0% by weight
(On the basis of all monomers that will finally react)
The polymer block B is formed by adding it to the polymer and polymerizing it.
To produce a block copolymer. 9. A process for producing a block copolymer, which comprises performing the following reaction (a ), reaction ( b) and reaction ( c ) in an inert organic solvent, and then coupling with a polyfunctional coupling agent. Method. (B Reaction) polymer monovinyl aromatic compound to form a block A 80 wt% to 100 wt% and a diene compound 20 wt% to 0 consisting wt% monomer 10 wt% to 50 wt%
Polymerization of (on the basis of all monomers to be finally reacted) with a monoorganolithium compound as an initiator to produce a polymer block A ( b reaction) Polyvinyl aromatic compound 0.02 wt% to 10.0 wt% ( The molar ratio of all the monomers to be finally reacted) is 0.03 to the monoorganolithium compound used in the reaction.
The reaction is carried out by adding it to the polymer of a reaction so that the ratio becomes 2.0. ( C reaction) Diene compound 50 for forming polymer block B
90% to 50% by weight of a monomer consisting of 50% to 100% by weight and 50% to 0% by weight of a monovinyl aromatic compound
(Final basis based on all the monomers to be reacted) is added to the polymer obtained by the reaction and polymerized to form a polymer block B to produce a block copolymer. 10. The method of claim 9, wherein the performing presence in Lee-Ha reaction of polar compounds. 11. The process according to claim 9 or 10, wherein the B reaction is characterized by the addition of diene compounds and / or monovinyl aromatic compound in the polyvinyl aromatic compound. 12. A process according to any one of claims 9 to 11, characterized in that continuously from Lee reaction to the final coupling reaction. 13. conducted interchanged the monomer used in Lee reaction and Ha reaction, after forming the polymer block B,
Claim 9, characterized in that to form the polymer block A
The manufacturing method according to any one of to 12 . 14. Further after i ~ c reactions that Lee counter
Response and / or repeat the same reaction as reaction Ha reaction method according to any one of claims 9 to 13 to produce a block copolymer, and then characterized by coupling. 15. b The process according to any one of claims 9 to 14, the reaction is characterized by performing at least once and before the coupling reaction after Ha reaction.