JP2500534B2 - Method for producing block copolymer resin - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a block copolymer composition having excellent transparency, impact resistance and rigidity.

[0002]

2. Description of the Related Art A block copolymer composed of a conjugated diene and a vinyl aromatic hydrocarbon is a thermoplastic resin having excellent transparency when the content of the vinyl aromatic hydrocarbon is relatively high, and having a better impact resistance than polystyrene. In recent years, the amount of its use has been increasing mainly in the fields of food packaging containers, daily sundries, toy boxes, light electric parts, etc. Various methods for producing such block copolymers are known, and JP-B-36-19286, JP-B-43-17979, JP-B-47-3252, and JP-B-47-289.
No. 15, JP-B-48-2423, JP-B-48
-4106, Japanese Patent Publication No. 57-49567 and Japanese Patent Publication No. 58-11446.

[0003]

However, the block copolymers disclosed in these methods do not have sufficient impact resistance, and improvement thereof is desired. In particular, extrusion molded products and injection molded products are inferior in the dart impact property, and cracks occur during molding, during transportation of the molded products, during use, and the like, which causes a serious problem in practical use. As a method for improving the impact resistance of a block copolymer, for example, Japanese Patent Publication No. 55-5544 discloses a method of blending two kinds of block copolymers having different styrene contents. It is still insufficient in terms of balance with impact resistance.

[0004]

Under these circumstances, the inventors of the present invention have studied to obtain a block copolymer resin having excellent transparency, impact resistance and rigidity, and as a result, have mainly conjugated diene. In the polymerization step of the polymer segment, it was found that the object can be achieved by using a conjugated diene having a specific amount of allenes, and by setting the maximum temperature of the polymerization temperature in the polymerization step to a specific range. Came to complete.

That is, according to the present invention, a polymer segment containing at least two vinyl aromatic hydrocarbons as a main component and at least one conjugated diene as a main component in a hydrocarbon solvent using an organolithium compound as an initiator is used. In producing a block copolymer resin having a united segment and having a weight ratio of vinyl aromatic hydrocarbon and conjugated diene of 55/45 to 95/5, a polymerizing step of polymer segment mainly composed of conjugated diene Among them, in at least one polymerization step, a conjugated diene having an allene content of 100 to 5000 ppm is used, and the maximum attainable temperature of the polymerization temperature in the polymerization step is in the range of 90 to 135 ° C. The present invention relates to a method for producing a copolymer resin. Hereinafter, the present invention will be described in detail.

In the method of the present invention, the hydrocarbon solvent is an aliphatic hydrocarbon such as butane, pentane, hexane, isopentane, heptane, octane, isooctane; cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, etc. Alicyclic hydrocarbons; or aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene can be used. These may be used alone or in combination of two or more. The hydrocarbon solvent is generally 50 to 2000 parts by weight based on 100 parts by weight of all the monomers used.

The organolithium compound is an organolithium compound having one or more lithium atoms bonded in the molecule,
Examples thereof include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, hexamethylene dilithium, butadienyl dilithium and isoprenyl dilithium. These are not only one, but two
You may mix and use more than one kind.

In the method of the present invention, the vinyl aromatic hydrocarbon is styrene, O-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-
There are dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene and the like, but styrene is particularly common. These may be used alone or in combination of two or more.

The conjugated diene is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1, 3-butadiene, 1,3
-Pentadiene, 1,3-hexadiene, etc.
Particularly common examples include 1,3-butadiene and isoprene. These may be used alone or in combination of two or more.

In the method of the present invention, the polymerization initiation rate of the initiator is adjusted, the polymerization reaction rate is adjusted, the microstructure (ratio of cis, trans and vinyl) of the polymerized conjugated diene portion is changed, and the conjugated diene and vinyl aroma are changed. A polar compound or a randomizing agent can be used for the purpose of adjusting the reactivity ratio of the group hydrocarbon. Examples of polar compounds and randomizing agents include ethers, amines, thioethers, phosphoramides, alkylbenzene sulfonates, and potassium or sodium alkoxides. Examples of suitable ethers are dimethyl ether, diethyl ether, diphenyl ether and tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether.

As the amines, tertiary amines such as trimethylamine, triethylamine, tetramethylethylenediamine, and cyclic tertiary amines can be used. Phosphines and phosphoramides include triphenylphosphine and hexamethylphosphoamide. Examples of the randomizing agent include potassium or sodium alkylbenzene sulfonate, potassium or sodium butoxide, and the like.

The block copolymer resin produced by the method of the present invention has at least two vinyl aromatic hydrocarbon-based polymer segments and at least one conjugated diene-based polymer segment. , The weight ratio of vinyl aromatic hydrocarbon to conjugated diene is 55/45 to 95 /
5, preferably 60/40 to 90/10, more preferably 65/35 to 85/15 block copolymer.
When the content of vinyl aromatic hydrocarbon is less than 55% by weight, rigidity and surface hardness are poor, and when it exceeds 95% by weight, impact resistance is poor, which is not preferable.

In the present invention, the polymer segment mainly composed of vinyl aromatic hydrocarbon is a polymer segment having a vinyl aromatic hydrocarbon content of 50% by weight or more, which comprises a conjugated diene and a vinyl aromatic hydrocarbon. Of the random copolymer part and / or the vinyl aromatic hydrocarbon polymer part. Further, the polymer segment mainly containing a conjugated diene is a polymer segment having a vinyl aromatic hydrocarbon content of less than 50% by weight, and a random copolymer part of a conjugated diene and a vinyl aromatic hydrocarbon and / or It is composed of conjugated diene polymer moieties. The vinyl aromatic hydrocarbon in the copolymer part may be distributed uniformly or in a taper shape. Further, in the copolymer portion, a plurality of portions in which vinyl aromatic hydrocarbons are evenly distributed and / or a portion in which taper distribution is formed may coexist.

The polymer structure of the block copolymer resin produced by the method of the present invention has the general formula (A) (AB) _{n + 1} (B) A- (BA) _n (C) B- (AB) _{n + 1} (In the above formula, A is a polymer segment mainly containing vinyl aromatic hydrocarbons, and B is a polymer segment mainly containing a conjugated diene. A segment and B segment Boundaries do not necessarily have to be clearly distinguished.
Is an integer of 1 or more. Generally, n is 5 or less. ) Linear block copolymer represented by

(D) [(BA) _n ] _{m + 2-} X (e) [(AB) _n ] _{m + 2-} X (f) [(BA) _n- B] _{m + 2-} X (to) [(AB) _n -A] _{m + 2-} X (In the above formula, A and B are the same as above, and X is, for example, silicon tetrachloride, tin tetrachloride, epoxidized large Residues of coupling agents such as soybean oil, carboxylic acid esters, polyhalogenated hydrocarbons and polyvinyl compounds, or residues of initiators such as polyfunctional organolithium compounds, wherein m and n are 1
Is an integer greater than or equal to. Generally, it is an integer of 1-5. ) Is a radial block copolymer represented by.

A particularly preferred block copolymer resin in the method of the present invention has a polymer structure represented by the general formula (1) B ₁ -A ₁ -B ₂ -A ₂ (2) A ₁ -B ₁ -A ₂ (3). _{B 1 -A 1 -B 2 -A 2} -B 3 (4) (B 1 -A 1 -B 2 -A 2) m + 2 -X (5) (A 1 -B 1 -A 2 -B 2 _{) m + 2 -X (6)} (B 1 -A 1 -B 2 -A 2 -B 3) m + 2 -X (7) (a 1 -B 1 -A 2) any of the _m + 2 -X It is a block copolymer resin represented by.

The feature of the method of the present invention is that the content of allenes is 100 to 5,000 in at least one of the polymerization steps of the polymer segment mainly containing the conjugated diene.
ppm, preferably 200 to 3000 ppm, more preferably 400 to 2000 ppm of conjugated diene, and polymerizing the conjugated diene-containing polymer segment using a conjugated diene containing allenes in the above specific range. The maximum temperature of the polymerization temperature in 90 ~ 135
℃, preferably 95-130 ℃, more preferably 100
It is to be in the range of to 125 ° C.

When the content of allenes is less than 100 ppm, impact resistance is poor, and when it exceeds 5000 ppm, transparency and rigidity are poor, which is not preferable. Further, when the maximum temperature of the polymerization temperature in the polymerization step in which the conjugated diene containing the allenes in the above specific range is used is less than 90 ° C, the impact resistance is poor, and when it exceeds 135 ° C, it is transparent. It is not preferable because it is inferior in properties and rigidity. In the present invention, the content of allenes is the ratio with respect to the conjugated diene used for polymerization.

In the method of the present invention, when a block copolymer resin having two or more polymerization steps of a polymer segment containing a conjugated diene as a main component is produced, at least one of the polymerization steps is conducted in the above-specified range of allenes. It is necessary to use a conjugated diene containing a polymer and to carry out polymerization at a polymerization temperature whose maximum temperature reaches the above specified range, but other polymerization steps may be carried out under polymerization conditions outside the range specified in the present invention.
Polymerization conditions outside the range specified in the present invention include, for example, using a conjugated diene having an allene content of less than 100 ppm to achieve a maximum temperature of 150 ° C. or lower, preferably 135 ° C. or lower. Content of 100 ~ 50
It means to polymerize at a polymerization temperature of less than 90 ° C. with a maximum reached temperature using 00 ppm of conjugated diene.

In the method of the present invention, in the case of producing a block copolymer resin having two or more polymerization steps of a polymer segment containing a conjugated diene as a main component, allenes containing the above-specified range of allenes are contained in all the polymerization steps. It is also possible to use a conjugated diene which is used, and to carry out polymerization at a polymerization temperature in which the maximum temperature reaches the above specified range. In the method of the present invention, when the polymerization in the polymerization step of the polymer segment having a conjugated diene as a main component is carried out under the specific conditions specified in the present invention, the maximum reached temperature of the polymerization temperature is the latter half of the monomer feed in the polymerization step It is recommended to adjust the polymerization temperature condition and the monomer feed condition so that they are expressed at the time when the monomer feed is finished or after that.

The polymer structure has the above general formula (1) to
In the block copolymer resin particularly preferable in the method of the present invention represented by (7), the polymerization step of carrying out the polymerization of the polymer segment mainly containing the conjugated diene under the specific conditions specified in the present invention is (1), (3), (4),
In (6), the B ₂ polymerization step, the general formula (2),
In (5) and (7), it is particularly recommended to use the B ₁ polymerization step.

On the other hand, in the method of the present invention, there are no particular restrictions on the polymerization conditions in the polymerization step of the polymer segment mainly containing vinyl aromatic hydrocarbon, and the polymerization can be carried out under the conventionally known polymerization conditions. The polymerization temperature in the polymerization step is generally 150 ° C. or lower, preferably 135 ° C. or lower, more preferably 120 ° C. or lower. In particular, in the polymerization step of the polymer segments mainly comprising vinyl aromatic hydrocarbon which is not the final step among the polymerization steps of the respective polymer segments constituting the block copolymer resin, the polymerization temperature is substantially 100 ° C.
The following is recommended. When the conjugated diene is copolymerized in the step of polymerizing the polymer segment mainly containing vinyl aromatic hydrocarbon, the conjugated diene may or may not contain allenes. When allenes are contained, the content thereof in the conjugated diene is preferably 5000 ppm or less, preferably 3000 ppm or less, more preferably 2000 ppm or less.

The allenes used in the method of the present invention include, for example, the general formula CH ₂ ═C═CHR (wherein R is 1 to 2 carbon atoms).
2, preferably 1 to 5 linear or branched alkyl groups or unsaturated hydrocarbon groups, phenyl groups, alkyl group-substituted phenyl groups, or allenes represented by hydrogen) can be used.

Specific examples of allenes represented by such a general formula are 1,2-propadiene, 1,2-butadiene, 1,2-pentadiene, 1,2-hexadiene,
1,2-heptadiene, 1,2-octadiene, 1,2
-Nonadiene, 1,2-decadiene and the like.
Preferred allenes are 1,2-propadiene and 1,2-
Butadiene, 1,2-pentadiene and 1,2-hexadiene. These allenes may be used alone or in combination of two or more.

The lower limit of the polymerization temperature for producing the polymer in the method of the present invention is generally -10 ° C, preferably 20.
C., more preferably 40.degree. Although the time required for the polymerization varies depending on the conditions, it is usually within 48 hours, and particularly preferably 0.5 to 10 hours. Further, it is desirable to replace the atmosphere of the polymerization system with an inert gas such as nitrogen gas. The polymerization pressure is not particularly limited as long as it is a pressure sufficient to maintain the monomer and solvent in the liquid phase within the polymerization temperature range specified in the present invention.
Further, it is necessary to take care so that impurities that inactivate the catalyst and the living polymer, such as water, oxygen, carbon dioxide gas, are not mixed into the polymerization system before and during the polymerization.

The number average molecular weight of the block copolymer resin obtained by the method of the present invention is generally 30,000 to 1,
, 000,000, preferably 50,000 to 800,000
00, more preferably 70,000 to 500,000. The number average molecular weight can be measured by, for example, gel permeation chromatography (GPC), and can be calculated according to a conventional method (for example, the method described in "Gel chromatography <Basics>" published by Kodansha). The calibration curve for GPC is prepared using standard polystyrene commercially available for GPC.

In the present invention, a polar group-containing compound may be reacted with the active terminal of the block copolymer resin to produce a terminal-modified block copolymer resin having a polar group-containing atomic group bonded in the polymer chain. it can. Here, the polar group-containing atomic group means an atomic group containing at least one atom selected from nitrogen, oxygen, silicon, phosphorus, sulfur and tin.

Specifically, a carboxyl group, a carbonyl group, a thiocarbonyl group, an acid halide group, an acid anhydride group, a carboxylic acid group, a thiocarboxylic acid group, an aldehyde group,
Thioaldehyde group, carboxylic acid ester group, amide group,
Sulfonic acid group, sulfonic acid ester group, phosphoric acid group, phosphoric acid ester group, amino group, imino group, nitrile group, pyridyl group, quinoline group, epoxy group, thioepoxy group, sulfide group, isocyanate group, isothiocyanate group, halogen An atomic group containing at least one polar group selected from a silicon oxide group, an alkoxy silicon group, a tin halide group, an alkyl tin group, a phenyl tin group and the like can be given.

More specifically, Japanese Patent Application No. 61-12917.
The terminal modification treatment agent described in No. 9 can be used,
The terminal modification agents described in the specification are within the scope of the present invention. The terminal modification treating agent for imparting to the polar group-containing atomic group is 0.1 to 10 mol, preferably 0.2 to 5 mol, and more preferably 0.5 to 1 atom equivalent of lithium metal at the polymer terminal. ~ 2 moles are used.

Further, in the present invention, the block copolymer resin or the terminal-modified block copolymer resin obtained above is partially or selectively hydrogenated by a hydrogenation reaction (hydrogenation reaction). You can The hydrogenation rate can be arbitrarily selected. When improving the heat deterioration resistance while maintaining the properties of the unhydrogenated polymer, the aliphatic double bond based on the conjugated diene is 3% or more and less than 80%. Hydrogenation is preferably 5% or more and less than 75%, and 80% or more, preferably 90% in the case of improving heat deterioration resistance and weather resistance.
The above hydrogenation is recommended.

In this case, an aromatic double compound based on a vinyl aromatic compound copolymerized with a polymer block A containing a vinyl aromatic compound as a main component and optionally a polymer block B containing a conjugated diene compound as a main component. The hydrogenation rate of the bond is not particularly limited, but the hydrogenation rate is preferably 20% or less. The amount of unhydrogenated aliphatic double bonds contained in the hydrogenated block copolymer can be easily known by an infrared spectrophotometer, a nuclear magnetic resonance apparatus or the like.

The catalyst used in the hydrogenation reaction is
(1) Supported heterogeneous catalyst in which a metal such as Ni, Pt, Pd, Ru, etc. is supported on carbon, silica, alumina, diatomaceous earth, and (2) organic acid salt such as Ni, Co, Fe, Cr Or, a homogeneous catalyst such as a so-called Ziegler type catalyst using an acetylacetone salt and a reducing agent such as organic Al, or a so-called organic complex catalyst such as an organometallic compound such as Ru or Rh is known.

As a concrete method, Japanese Patent Publication No. 42-870.
4, JP-B-43-6636, JP-A-59-133203, JP-A-60-22014.
According to the method described in Japanese Patent Publication No. 7, a hydrogenated block copolymer resin can be synthesized by hydrogenating in the presence of a hydrogenation catalyst in an inert solvent. At that time, the hydrogenation rate of the aliphatic double bond based on the conjugated diene compound in the block copolymer resin can be controlled to an arbitrary amount by adjusting the reaction temperature, the reaction time, the hydrogen supply amount, the catalyst amount and the like. .

In the production of the block copolymer resin by the method of the present invention, an additive such as a reaction terminator is added to the polymer solution after polymerization, the polymer solution after terminal modification treatment, and further the polymer solution after hydrogenation reaction. It can be added.
Examples of the reaction terminator and the like include (a) water, (b) alcohol,
Those selected from (c) inorganic acids and (d) organic acids are preferable. As the alcohol, lower alcohols such as methanol, ethanol and propanol, higher alcohols having 6 to 18 carbon atoms and polyhydric alcohols (ethylene glycol, propylene glycol, glycerin, etc.) can be used.

The inorganic acids used in the present invention are chlorine, sulfur,
Examples thereof include acids formed by bonding an acid group containing a nonmetal such as nitrogen and phosphorus with hydrogen, such as hydrochloric acid, sulfuric acid, nitric acid, boric acid, phosphoric acid, and other carbonic acid. Further, the organic acid used in the present invention is an organic compound having acidity in a broad sense, such as carboxylic acid,
Examples thereof include compounds such as sulfonic acid, sulfinic acid, and phenol, and organic compounds containing a carboxyl group are preferable, and the following compounds are preferable.

(1) Fatty acids having 8 or more carbon atoms (2) Rosinic acid (3) Oxycarboxylic acid (4) Aromatic carboxylic acid A particularly preferable organic acid is the fatty acid of (1), and its specific example is octyl acid. Examples thereof include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid, behenic acid, castor-hardened fatty acid, tallow fatty acid, or a mixture thereof.

In the method of the present invention, the pH of the polymer solution after polymerization, the polymer solution after terminal modification treatment, and further the polymer solution after hydrogenation reaction is 4 to 10, preferably 5 to 9, and more preferably Is preferably adjusted to a range of 6-8. Such a treatment is effective in preventing coloration when the stabilizer is added.

In the present invention, the block copolymer resin may be blended with a thermoplastic resin or a rubber-like polymer. Examples of thermoplastic resins are given below. Polystyrene such as polystyrene, impact-resistant rubber modified styrene polymer, acrylonitrile-styrene copolymer, styrene-maleic anhydride copolymer, acrylonitrile-butadiene-styrene copolymer, methacrylic acid ester-butadiene-styrene copolymer resin.

Polyethylene, a copolymer of ethylene containing 50% or more of ethylene and another monomer copolymerizable therewith, for example, an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer and a hydrolyzate thereof, Polyethylene resins such as ethylene-acrylic acid ionomer and chlorinated polyethylene.

Polypropylene, a copolymer of propylene containing 50% or more of propylene and a monomer copolymerizable therewith, for example, polypropylene such as propylene-ethylene copolymer, propylene-ethyl acrylate copolymer and chlorinated polypropylene. Resin. Polybutene-1, a polybutene-based resin which is a copolymer of butene-1 and another monomer copolymerizable therewith.

Polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride containing 50% or more of vinyl chloride and / or vinylidene chloride, and polychlorine which is a copolymer of vinylidene chloride and another monomer copolymerizable therewith. Vinyl resin. A polyvinyl acetate-based resin which is a copolymer of vinyl acetate having a vinyl acetate content of 50% or more and another copolymerizable monomer, and a hydrolyzate thereof.

Polymers of acrylic acid and its esters and amides, methacrylic acid and its esters and amides, and polyacrylates that are copolymers with other copolymerizable monomers containing 50% or more of these acrylic acid-based monomers. resin. Acrylonitrile and / or methacrylonitrile polymer, 50% of these acrylonitrile monomers
A nitrile resin which is a copolymer with the other copolymerizable monomer contained above.

Linear polymers in which the structural units of the polymer are bonded by repeating amide group bonds, for example, ring-opening polymers of ε-aminocaprolactam and ω-aminolaurolactam, condensation polymers of ε-aminoundecanoic acid, Polyamide resins such as polycondensates of hexamethylenediamine and dibasic acids such as adipic acid and sebacic acid. A linear polymer in which the structural units of the polymer are bonded by repeating ester bonds, for example, a dibasic acid such as phthalic acid or isophthalic acid or a derivative thereof, and a glycol component such as ethylene glycol, propylene glycol or butylene glycol. Polyester resin that is a condensate.

A polyacetal resin such as a polyphenylene ether resin or a grafted polyphenylene ether resin obtained by graft-polymerizing a vinyl-substituted aromatic hydrocarbon on the resin, a polyphenylene sulfide resin, polyoxymethylene, a copolymer of trioxane and alkylene oxide, and the like. Linear polymers in which the constituent units of the polymer are linked by repeating carbonic acid ester type bonds, eg 4,4 '
A polycarbonate resin such as a polymer obtained by the reaction of a dihydroxy compound such as dihydroxydiphenylalkane or 4,4'-dihydroxydiphenylsulfide with phosgene, or a polymer obtained by the transesterification reaction of the dihydroxy compound and diphenylcarbonate.

Polysulfone resins such as polyether sulfone and polyallyl sulfone. A thermoplastic polyurethane resin obtained by a polyaddition reaction between a diisocyanate component and a glycol component. Trans polybutadiene, 1,
Polybutadiene-based resins such as 2-polybutadiene.

A polyarylate resin which is a polycondensation polymer composed of bisphenol A and a phthalic acid component. Examples thereof include a fluororesin, a polyoxybenzoyl-based resin, and a polyimide-based resin having a structure in which a part or all of hydrogen in a chain hydrocarbon polymer compound is replaced with fluorine.

As the rubbery polymer, polybutadiene, polyisoprene, styrene-butadiene copolymer (butadiene content of less than 55% by weight), styrene-isoprene copolymer (isoprene content of less than 55% by weight),
Butadiene-acrylonitrile copolymer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, polybutene, thermoplastic polyester elastomer, thermoplastic polyamide elastomer, thermoplastic polyurethane elastomer, silicone rubber, epichlorohydrin rubber, acrylic rubber, ethylene -Vinyl acetate copolymer fluororubber and the like.

In the present invention, the mixing ratio (weight ratio) of the block copolymer resin and the thermoplastic resin or the rubber-like polymer is generally 99/1 to 3/97, preferably 97/3 to. It is 5/95. Further, various stabilizers, pigments, antiblocking agents, antistatic agents, lubricants, softening agents, plasticizers, tackifying resins, etc. may be added to the block copolymer resin obtained by the method of the present invention. it can. Specifically, the additives described in "Practical Handbook of Additives for Plastics and Rubbers" (Chemical Industry Co., Ltd.) can be used. These additives are generally used in the blending amounts described in these manuals. Especially for stabilizers, it is recommended to use the following stabilizers. (A) Phenolic compound represented by the following general formula [I]

[0049]

Embedded image (In the above formula, R ₁ is an alkyl group having 1 to 22 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a tert-butyl group, a tert-amyl group, a tert-hexyl group, tert-heptyl group, t
It is an ert-octyl group. Preferred R ₁ is methyl group, tert-butyl group, tert-amyl group, te
It is an rt-hexyl group. R ₂ is an alkenyl group having 2 to 4 carbon atoms, and specific examples thereof include an ethenyl group, an isopropenyl group, a propenyl group, an isobutenyl group and a butenyl group. Particularly preferred is the ethenyl group. R ₃
Is an alkyl group having 4 to 22 carbon atoms (straight or branched) or a cyclohexyl group. R ₃ preferably has 4 carbon atoms
To 12 branched alkyl groups, and specific examples include ter
t-butyl group, tert-amyl group, tert-hexyl group, tert-heptyl group, and tert-octyl group. R ₄ is hydrogen or an alkyl group having 1 to 22 carbon atoms, and preferable specific examples thereof include hydrogen, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group and the like).

(B) Phenolic Stabilizer Other Than the Phenolic Compound The suitable phenolic stabilizer is tetrakis [methylene-3- (3 ', 5'-di-tert-butyl-4'-hydroxy]. Phenyl) propionate] methane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 2,6-di-tert-butyl-4 −
Methylphenol, 4-hydroxymethyl-2,6-di-tert-butylphenol, 2,4-bis- (n-
Octylthio) -6- (4-hydroxy-3,5-di-
tert-Butylanilino) -1,3,5-triazine, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, triethylene glycol-bis [3- (3-tert-butyl- 5-Methyl-4-hydroxyphenyl) propionate], 1,3,5-tris- (4-tert-butyl-
3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid, 2,2'-methylene-bis- (4-methyl-6)
-Tert-butylphenol), 3,9-bis [2-
{3- (3-tert-butyl-4-hydroxy-5-
Methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, 4-hydroxymethyl-2,6
-Di-tert-butylphenol, 2,6-di-te
rt-Butyl-4-ethylphenol, butylated hydroxyanisole, 2,2'-dihydroxy-3,3'-
Dicyclohexyl-5,5'-dimethyl-diphenylmethane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 4,4 '
-Butylidenebis (6-tert-butyl-m-cresol, 4,4'-thiobis (3-methyl-6-tert)
-Butylphenol), bis (3-cyclohexyl-2)
-Hydroxy-5-methylphenyl) methane, 2,2 '
-Methylenebis (4-ethyl-6-tert-butyl-
Phenol), 1,1-bis (2′-methyl-4′-hydroxy-5′-tert-butyl-phenyl) butane, and the like.

(C) Sulfur-Based Stabilizer, Phosphorus-Based Stabilizer Specific examples of sulfur-based stabilizers include dilauryl-3,
3'-thiodipropionate, dimyristyl-
3,3'-thiodipropionic acid ester, distearyl-3,3'-thiodipropionic acid ester, lauryl stearyl-3,3'-thiodipropionic acid ester, pentaerythritol-tetrakis- (β-lauryl-thio -Propionate), 3,9-bis- (2-dodecylthioethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane and the like.

Specific examples of the phosphorus-based stabilizer include tris (nonylphenyl) phosphite, cyclic neopentanetetraylbis (octadecylphosphite), tris (2,4-di-tert-butylphenyl) phosphite, 4,4-butylidene-bis (3-
Methyl-6-tert-butylphenyl-di-tridecyl) phosphite, 4,4'-biphenylenediphosphinic acid tetrakis (2,4-di-tert-butylphenyl), cyclic neopentanetetraylbis (2,4-) And di-tert-butylphenyl) phosphite.

These stabilizers are in the range of 0.01 to 5 parts by weight, preferably 0.05 to 4 parts by weight, more preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the block copolymer resin. Used in. These stabilizers can be used in combination of two or more kinds. The preferred combination is (A) +
(C), (B) + (C), (A) + (B), (A) +
(B) + (C).

[0054]

The block copolymer resin obtained by the method of the present invention is transparent and has excellent impact resistance, and can be used as a molding material for various molded articles. That is, the block copolymer resin obtained by the method of the present invention, as it is or after being colored, is an extrusion-molded product such as a sheet or a film, as well as vacuum-molded or pressure-molded products thereof, by the same processing means as an ordinary thermoplastic resin. Molded products thermoformed by methods such as molding, specifically food containers and packaging,
It can be used in a wide range of container packaging materials such as blister packaging materials, packaging films for fruits and vegetables and confectionery. In addition, injection molding, blow molding methods, toys, daily necessities,
It can be used for applications where ordinary general-purpose thermoplastic resins are used, such as food packaging containers, miscellaneous goods, and light electric components.

[0055]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. In the following examples, the cyclohexane solution containing styrene and / or butadiene was a solution having a monomer concentration of 25% by weight.

Example 1 In a nitrogen gas atmosphere, 0.055 parts by weight of n-butyllithium was added to a cyclohexane solution containing 15 parts by weight of styrene and 0.06 parts by weight of tetrahydrofuran, and polymerized at about 80 ° C. for 20 minutes ( After the first polymerization step) 1,2
A cyclohexane solution containing 20 parts by weight of 1,3-butadiene containing 800 ppm of butadiene with a metering pump;
It added and polymerized over 5 minutes. During this period, the polymerization temperature was gradually increased from about 80 ° C., and the polymerization temperature was controlled so that the polymerization temperature was 105 ° C. immediately after the completion of the monomer feed (second polymerization step).

After that, it was held as it was for 10 minutes. Thereafter, a cyclohexane solution containing 65 parts by weight of styrene was further added by a metering pump over 1 hour to polymerize.
During this period, the polymerization temperature was gradually decreased from 105 ° C., and the polymerization temperature was controlled so that the polymerization temperature was about 80 ° C. immediately after the completion of the monomer feed (third polymerization step).

After the completion of the polymerization, 0.5 part by weight of water was added as a deactivator, and then about 0.04 part by weight of carbon dioxide was added to neutralize the pH of the polymerization solution to about 7. Next, as a stabilizer, 2-tert-butyl-6- (3-tert-butyl-
0.5 parts by weight of 2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, tris (2,4-
Di-tert-butylphenyl) phosphite was added to 0.
2 parts by weight was added. The physical properties of the obtained block copolymer resin are shown in Table 1, and it was a polymer excellent in impact resistance, transparency and rigidity.

Comparative Example 1 1,3-Butadiene used in the second polymerization step was 1,
A block copolymer resin was produced in the same manner as in Example 1 except that 1,3-butadiene having a 2-butadiene content of less than 10 ppm was used. The obtained block copolymer resin was inferior in impact resistance.

Comparative Example 2 1,3-butadiene used in the second polymerization step was 1,
A block copolymer resin was produced in the same manner as in Example 1 except that 1,3-butadiene having a 2-butadiene content of 6000 ppm was used. The resulting block copolymer resin was inferior in impact resistance and transparency.

Comparative Example 3 The amount of styrene used in the first polymerization step was 9.5 parts by weight, and the amount of 1,3-butadiene (1,2-butadiene content 800 ppm) used in the second polymerization step was 50 parts by weight. A block copolymer resin was produced in the same manner as in Example 1 except that the amount of styrene used in the third polymerization step was 40.5 parts by weight. The block copolymer resin obtained was inferior in rigidity.

Comparative Example 4 The amount of styrene used in the first polymerization step was 18 parts by weight,
Example 1 except that the amount of 1,3-butadiene (1,2-butadiene content 800 ppm) used in the polymerization step was 3 parts by weight and the amount of styrene used in the third polymerization step was 79 parts by weight.
A block copolymer resin similar to the above was produced. The obtained block copolymer resin was inferior in impact resistance.

[0063]

[Table 1]

Example 2 In a nitrogen gas atmosphere, 0.07 parts by weight of n-butyllithium was added to a cyclohexane solution containing 8 parts by weight of 1,3-butadiene having a 1,2-butadiene content of less than 10 ppm to carry out polymerization. Polymerization was performed for 30 minutes under conditions such that the maximum temperature reached was 85 ° C (first polymerization step).
Then, a cyclohexane solution containing 15 parts by weight of styrene was added with a metering pump over 20 minutes to polymerize at a polymerization temperature of about 80 to 90 ° C (second polymerization step).

Next, the 1,2-butadiene content is 400
A cyclohexane solution containing 22 parts by weight of ppm 1,3-butadiene was added by a metering pump for 30 minutes to carry out polymerization. During this period, the polymerization temperature was gradually increased, and the polymerization temperature was controlled so that the polymerization temperature immediately after the completion of the monomer feed was 108 ° C. (maximum temperature reached) (third polymerization step). Thereafter, a cyclohexane solution containing 55 parts by weight of styrene was further added by a metering pump over 1 hour to polymerize. During this time, the polymerization temperature is gradually lowered from 108 ° C,
The polymerization temperature was controlled so that the polymerization temperature immediately after the completion of the monomer feed was about 80 ° C. (fourth polymerization step).

After the completion of the polymerization, 0.5 part by weight of water was added as a deactivator, and then about 0.05 part by weight of carbon dioxide was further added to neutralize the polymerization solution. Then 2-tert as a stabilizer
-Amyl-6- [1- (3,5-di-tert-amyl-2-hydroxyphenyl) ethyl] -4-tert-
0.5 parts by weight of amylphenyl acrylate, n-octadecyl-3- (3 ', 5'-di-tert-butyl-
0.2 parts by weight of 4'-hydroxyphenyl) propionate was added. The physical properties of the obtained block copolymer resin are shown in Table 2, and it was a polymer excellent in impact resistance, transparency and rigidity.

Example 3 As 1,3-butadiene used in the first polymerization step,
A block copolymer resin was produced in the same manner as in Example 2 except that 1,3-butadiene having a content of 2-butadiene of 400 ppm was used. The physical properties of the obtained block copolymer resin are shown in Table 2.

Comparative Examples 5 to 7 Table 2 shows the contents of 1,2-butadiene in 1,3-butadiene used in the first and third polymerization steps and the maximum temperature reached in these polymerization steps. A block copolymer resin was produced in the same manner as in Example 2 except that the conditions shown were used. The block copolymer resins obtained were all inferior in impact resistance.

[0069]

[Table 2]

Example 4 In a nitrogen gas atmosphere, sec-butyllithium was added to a cyclohexane solution containing 60 parts by weight of styrene in an amount of 0.0.
6 parts by weight was added, and the polymerization was carried out for 30 minutes under the condition that the highest temperature reached at the polymerization temperature was 75 ° C. Then, a cyclohexane solution containing 10 parts by weight of styrene and 0.05 part by weight of sec-butyllithium were added, and the mixture was heated at about 75 ° C. for 20 hours.
Polymerized for minutes.

Next, the 1,2-butadiene content is 600
A cyclohexane solution containing 15 parts by weight of ppm 1,3-butadiene was added by a metering pump for 20 minutes for polymerization. During this period, the polymerization temperature was gradually increased, and the polymerization temperature was controlled so that the polymerization temperature immediately after completion of the monomer feed was 103 ° C. (maximum temperature reached). Then se
After adding 0.02 parts by weight of c-butyllithium, a cyclohexane solution containing 5 parts by weight of styrene was added with a metering pump 1
It added and polymerized over 0 minute. During this period, the polymerization temperature is 1
The temperature was gradually decreased from 03 ° C, and the polymerization temperature was controlled so that the polymerization temperature immediately after the completion of the monomer feed was about 80 ° C. Thereafter, a cyclohexane solution containing 10 parts by weight of 1,3-butadiene having a 1,2-butadiene content of 600 ppm was added by a metering pump for 20 minutes to carry out polymerization. During this period, the polymerization temperature was gradually raised, and the polymerization temperature was controlled so that the polymerization temperature immediately after the completion of the monomer feed was 97 ° C. Then, 0.35 parts by weight of tetrachlorosilane was added to cause a coupling reaction to produce a block copolymer resin having a radial structure.

The block copolymer resin thus obtained was treated with 2-tert-amyl-6- [1-
0.5 parts by weight of (3,5-di-tert-amyl-2-hydroxyphenyl) ethyl] -4-tert-amylphenyl acrylate, tris (2,4-di-tert).
0.1 parts by weight of -butylphenyl) phosphite and 0.5 parts by weight of tris (2,4-di-tert-butylphenyl) phosphite were added. The block copolymer resin had a dart impact value of more than 100 kg · cm, a flexural modulus of 15000 kg / cm ² , and a haze of 3%.

Examples 5 to 9 The block copolymer resins obtained in Example 1 were used as disclosed in JP-A 59-59.
Hydrogenated with a Ti-based hydrogenation catalyst described in Japanese Patent Publication No. 133203/1993,
The hydrogenation rates of the butadiene part are 15%, 35% and 8%, respectively.
Five types of 5%, 95% and substantially 100% block copolymer resins were prepared.

Example 10 The living polymer of the block copolymer resin obtained in Example 10 was reacted with N-methylpyrrolidone (used in an equivalent amount to the initiator n-butyllithium used for the polymerization),
An end-modified block copolymer resin was produced.

Examples 11 and 12 and Comparative Example 8 A composition obtained by blending polystyrene in the block copolymer resin of Example 3, polystyrene in the block copolymer resin of Example 2, and rubber-modified high impact polystyrene (HIPS). Was prepared, and a sheet having a thickness of 0.7 mm was formed by a sheet extruder. The physical properties of the obtained sheet are shown in Table 3. Next, as a comparative example, the same composition as in Example 12 was prepared using the block copolymer resin of Comparative Example 6, and a similar sheet was molded. The physical properties of the sheet are shown in Table 3.

[0076]

[Table 3]

Claims (1)

(57) [Claims] 1. A polymer solvent containing at least two vinyl aromatic hydrocarbon-based polymer segments and at least one conjugated diene-based polymer segment in an hydrocarbon solvent using an organolithium compound as an initiator. However, the weight ratio of vinyl aromatic hydrocarbon and conjugated diene is 55/45 to 95 /
In producing the block copolymer resin of 5, the content of allenes in at least one of the polymerization steps of the polymer segment containing a conjugated diene as a main component is 10 or more.
A process for producing a block copolymer resin, which comprises using a conjugated diene in an amount of 0 to 5000 ppm and setting the maximum temperature reached in the polymerization step to 90 to 135 ° C.