JPH06279650A - Block copolymer composition having excellent thermal stability and color change resistance during long-term storage - Google Patents

Abstract

PURPOSE:To obtain the subject composition having excellent thermal stability and color change resistance during long-term storage by blending a block copolymer comprising a monoalkenyl aromatic compound and a conjugated diene with specific two kinds of phenolic stabilizers. CONSTITUTION:(A) 100 pts.wt. of a block copolymer comprising a polymer segment consisting essentially of a monoalkenyl aromatic compound and a polymer segment consisting essentially of a conjugated diene, having 5-95wt.% of a monoalkenyl aromatic compound content or a mixture of the copolymer, a thermoplastic resin and/or a rubber-like polymer are blended with (B) 0.005-0.2 pt.wt. of a phenolic stabilizer of formula I [R1 and R3 are CH2-S-R5 (R5 is 1-18C alkyl); R2 is H or methyl; R4 is 1-8C alkyl or 5-12C cycloalkyl] and (C) 0.05-2 pts.wt. of a stabilizer selected from phenolic compounds of formula II and formula III (R6 is R5; R7 is tert-amyl, cyclohexyl, etc.; R8 to R11 are H or 1-18C alkyl) to give the objective composition.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a block copolymer comprising a monoalkenyl aromatic compound and a conjugated diene or a mixture of the block copolymer with a thermoplastic resin and / or a rubbery polymer, and a specific phenol. The present invention relates to a block copolymer composition comprising a system stabilizer and having excellent thermal stability and resistance to yellowing during long-term storage.

[0002]

2. Description of the Related Art A block copolymer composed of a monoalkenyl aromatic hydrocarbon and a conjugated diene is a vulcanized natural rubber or a vulcanized natural rubber when the content of the monoalkenyl aromatic hydrocarbon is relatively low. Since it has elasticity similar to that of synthetic rubber at room temperature and has workability similar to that of thermoplastic resin at high temperature, it is widely used in the fields of footwear, plastic modification, asphalt, adhesives and the like.

When the content of monoalkenyl aromatic hydrocarbons is relatively high, a transparent thermoplastic resin having excellent impact resistance can be obtained. At the same time, the usage is diversifying. However, a block copolymer composed of a monoalkenyl aromatic hydrocarbon and a conjugated diene has poor thermal stability because it has a carbon-carbon double bond in the molecule,
There is a problem that the properties of the block copolymer itself, such as elastic properties, adhesiveness, and impact resistance cannot be sufficiently improved. Therefore, in order to improve the thermal stability of such block copolymers, phenolic stabilizers, phosphorus stabilizers, sulfur stabilizers and the like are used.

[0004]

For example, the most widely used phenolic stabilizer BHT (2,6-
In the case of di-tert-butyl-4-methylphenol), it has a relatively high anti-oxidation function and heat resistance, but when the molding temperature is high or the molding time is long, it easily volatilizes. It was necessary to use a large amount. Also, during storage of the block copolymer composition,
There are problems such as yellowing of the composition.

On the other hand, phosphorus-based stabilizers and sulfur-based stabilizers
Although the heat stabilizing effect is improved when used in combination as a secondary stabilizer, phosphorus-based stabilizers have a problem of hydrolysis, and sulfur-based stabilizers can be used under relatively severe conditions under high temperature heating. There is a problem in that it may be easily colored or may give off an odor, making it difficult to obtain a stable effect.
Similar problems occur with other stabilizers, and their thermal stabilizing effect and discoloration resistance during long-term storage have not been sufficient.

As described above, the conventional stabilizers, whether used alone or in combination of several kinds, have limited thermal stabilization effects and discoloration resistance during long-term storage. Therefore, depending on the industrial field to be used, it is not possible to obtain a product satisfying these points, and a block copolymer composition having excellent discoloration resistance during long-term storage and high thermal stability is long. Was wanted.

[0007]

[Means for Solving the Problems] Under these circumstances,
The present inventors have found that color tone and thermal stability, for example, block copolymers that are resistant to discoloration during long-term storage, have excellent stability of physical properties under high-temperature heating, and have a high effect of suppressing the generation of gel-like substances. As a result of examining the method for obtaining the composition, it was found that a block copolymer composition having excellent thermal stability and discoloration resistance during long-term storage can be obtained by combining a specific phenolic compound, and the present invention Came to.

That is, the present invention includes: (a) a polymer segment mainly containing at least one monoalkenyl aromatic compound and a polymer segment mainly containing at least one conjugated diene; Block copolymer having a compound content of 5 to 95% by weight or the block copolymer and thermoplastic resin and / or
Or a mixture with a rubber-like polymer, 100 parts by weight (b) a stabilizer which is a phenolic compound represented by the following general formula, 0.005-0.2 polymer parts

[0009]

[Chemical 1]

(Wherein R ₁ and R ₃ are —CH ₂ —S—R
₅ and R ₅ represents an alkyl group having 1 to 18 carbon atoms. R ₂ represents a hydrogen atom or a methyl group. R ₄ represents an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 12 carbon atoms. ) (C) At least one stabilizer selected from phenolic compounds represented by the following general formulas [II] and [III],
... 0.05 to 2.0 parts by weight

[0011]

[Chemical 2]

(In the above formula, R ₆ has 1 to 1 carbon atoms.
8 is an alkyl group, R ₇ is a tert-butyl group, a tert-amyl group or a cyclohexyl group,
R _8, R _9, R ₁₀ and R ₁₁ are the same or different, and each represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. And a block copolymer excellent in thermal stability and discoloration resistance during long-term storage. The present invention will be described in detail below.

The block copolymer used in the present invention is
It has at least one polymer segment mainly containing a monoalkenyl aromatic compound and at least one polymer segment mainly containing a conjugated diene, and the content of the monoalkenyl aromatic compound is 5 to 95% by weight, preferably 10-90
It is a block copolymer or a mixture of the block copolymer and a thermoplastic resin and / or a rubber-like polymer in a weight percentage.

When the content of the monoalkenyl aromatic compound is 60% by weight or less, preferably 55% by weight or less, the block copolymer exhibits properties as a thermoplastic elastic material, and the content of the monoalkenyl aromatic compound is included. If the amount exceeds 60% by weight, preferably 65% by weight or more, the properties as a thermoplastic resin are exhibited. When the content of the monoalkenyl aromatic compound is less than 5% by weight, the block copolymer is inferior in mechanical properties such as tensile strength, which is a preferable property as a thermoplastic elastic body, and when the content is 95% by weight or more. Is inferior in mechanical strength such as impact resistance, which is a preferable property as a thermoplastic resin.

Examples of the monoalkenyl aromatic compound used here include styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, p-tert-butylstyrene and the like. The body is exemplified, and styrene is preferable among them. These monomers may be used alone or in combination of two or more.

On the other hand, as the conjugated diene, for example, 1,3
-Butadiene, isoprene, 2,3-dimethyl-1,3
Examples include monomers such as butadiene and 1,3-pentadiene, and among them, 1,3-butadiene and isoprene are preferable. These monomers may be used alone or in combination of two or more.

The block copolymer used in the present invention is
Following general formula: (A-B) _n, in _{(A-B) n A,} (A-B) n X ( wherein, A is a polymer block consisting mainly of monoalkenyl aromatic compound, B is A conjugated diene compound polymer or a polymer block mainly composed of a conjugated diene, wherein X is, for example, silicon tetrachloride, tin tetrachloride, a bisphenol type epoxy compound, an epoxy soybean oil, a polyhalogenated hydrocarbon, a carboxylic acid ester, etc. Represents a residue of an agent or a residue of a polyfunctional organolithium compound, etc., n is an integer of 1 or more.), And is a block copolymer composed of a conjugated diene.

The polymer block mainly containing a monoalkenyl aromatic compound means a homopolymer block of a monoalkenyl aromatic compound or a monoalkenyl aromatic compound 5.
The monoalkenyl aromatic compound-conjugated diene copolymer block containing more than 0% by weight is shown. The polymer block containing a conjugated diene as a main component means a conjugated diene homopolymer block or a conjugated diene-monoalkenyl aromatic compound copolymer block containing more than 50% by weight of a conjugated diene.

The monoalkenyl aromatic hydrocarbons in the copolymer block are non-uniform (tapered) even if they are evenly distributed.
May be distributed in A plurality of uniformly distributed portions and / or non-uniformly distributed portions may coexist in each block. The block copolymer used in the present invention may be any mixture of the block copolymers represented by the above general formula.

The number average molecular weight of the block copolymer used in the present invention is 10,000 to 1,000,000, preferably 20,000 to 800,000. If the number average molecular weight is less than 10,000, mechanical properties such as tensile strength are deteriorated, which is not preferable. Further, if the number average molecular weight exceeds 1,000,000, the viscosity is too high, resulting in poor dispersion and poor processability when compounded as a material for various applications such as adhesives and footwear, which is not preferable. .

The above general formulas (AB) _n , (AB)
_The block copolymers represented by _n A and (AB) _n X are
N-butyllithium, sec-butyllithium, isopropyllithium, phenyllithium, etc. in an inert hydrocarbon solvent such as cyclohexane, benzene, n-hexane, etc.
Alternatively, it can be obtained by a so-called anionic polymerization method using an organic lithium compound as an initiator as described in JP-A-58-136603.

For example, polystyrene-polybutadiene-
When obtaining a block copolymer having an ABA structure represented by polystyrene, a predetermined amount of n-butyllithium is added to a styrene monomer mixed with the above inert solvent such as cyclohexane under an atmosphere of an inert gas such as nitrogen. An organolithium initiator such as the above is added to form a polystyrene block, and then a butadiene monomer mixed solvent is added to form a polystyrene-polybutadiene type 2 polymer. After that, styrene monomer is further added to obtain the desired A-
There is a method of obtaining a type 3 block copolymer having a BA structure.

In addition, it is also possible to obtain a block copolymer having an (AB) _n X structure by adding a coupling agent such as silicon tetrachloride after forming the above-mentioned type 2 block polymer. In addition, depending on the case, so-called polar compounds such as tetrahydrofuran, diethylene glycol dimethyl ether, and tetramethylethylenediamine may be added to the polymerization system. The method for producing the block copolymer may be various methods depending on the intended polymer and is not particularly limited.

The composition of the present invention is characterized by blending 0.005 to 0.2 part by weight of the phenolic compound represented by the general formula (I) per 100 parts by weight of the block copolymer. The compounding amount of the general formula [I] is 0.005
If it is less than part by weight, the stabilizing effect is small and the combined effect with the phenol compound represented by the general formulas [II] and [III] is also reduced. Further, if the blending amount exceeds 0.2 parts by weight, the coloration of the block copolymer composition becomes severe when heated at a high temperature for a long time, which is not preferable. A more preferable blending amount is 0.01 to 0.1 part by weight, and further preferably 0.02 to 0.05 part by weight.

In the compound represented by the general formula [I] used in the present invention, the substituents R ₁ and R ₃ are --C.
H ₂ —S—R ₅ and R ₅ is an alkyl group having 1 to 18 carbon atoms, preferably n-octyl group or n-
It is a dodecyl group. The substituent R ₂ is a methyl group or a hydrogen atom, and when the substituent R ₄ is other than a methyl group, it represents a methyl group.

The substituent R ₄ having 1 to 8 carbon atoms is a methyl group, an ethyl group, an n-butyl group, a sec-butyl group,
A tert-butyl group and the like can be mentioned, but a methyl group or a tert-butyl group is preferable. 5 carbon atoms
Examples of the substituent R ₄ as the cycloalkyl group of 12 include a cyclopentyl group, a cyclohexyl group, a cyclopentyl group, a cyclooxyl group and the like, but a cyclohexyl group is preferable. Specific examples of the phenolic compound represented by the general formula [I] include 2,4-bis (n-octylthiomethyl) -6-methylphenol and 2,4-bis (n-dodecylthiomethyl) -6-. Methylphenol,
2,4-bis (phenylthiomethyl) -3-methyl-6
-Tert-butylphenol and the like can be mentioned. Most preferably 2,4-bis (n-octylthiomethyl)
It is -6-methylphenol.

Further, the composition of the present invention has the general formula [I
I], at least one stabilizer selected from the phenolic compounds represented by [III] 0.05 to 2.0 parts by weight, preferably 0.1 to 1.5 parts by weight, more preferably 0.2 to It is essential to add 1.0 part by weight. When the compounding amount of at least one stabilizer selected from the phenolic compounds represented by the general formulas [II] and [III] is less than 0.05 parts by weight, the stabilizing effect is small, and The combined effect is small. In addition, the compounding amount is 2.0
Even if it exceeds the weight part, there is substantially no effect on heat stabilization, and unnecessary addition is economically disadvantageous. A more preferable blending amount is 0.1 to 1.5 parts by weight, and further more preferable is 0.1.
2 to 1.0 parts by weight.

Specific examples of the phenolic compounds represented by the general formulas [II] and [III] include 2-tert-amyl-6- [1- (3,5-di-tert-amyl-2.
-Hydroxyphenyl) ethyl] -4-tert-amylphenyl acrylate, 2-tert-butyl-6-
(3′-tert-butyl-5′-methyl-2′-hydroxypentyl) -4-methylphenyl acrylate,
2,4-di-tert-butyl-6- (3 ', 5'-di-tert-butyl-2'-hydroxybenzyl) phenyl acrylate, 2,2'-ethylidene-4,6-di-tert-butylphenol -(4 ', 6'-di-t
ert-butyl-phenyl acrylate), 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,
1-di-methylethyl} 2,4,8,10-tetraoxaspiro [5,5] undecane and the like can be mentioned.

The composition of the present invention comprises the phenolic compound represented by the general formula [I] and the general formula [II] and / or
Alternatively, it is essential to mix the phenolic compound represented by [III], but if there is no problem even if the phosphorus compound is compounded in the intended use, the phosphorus compound is added to the composition of the present invention in an amount of 0. It is preferable to add 1 to 2.0 parts by weight and combine them, because the thermal stability can be further improved and the color can be changed.

Specific examples of such phosphorus compounds include tris (nonylphenyl) phosphite, cyclic neopentanetetraylbis (octadecylphosphite), tris (2,4-di-tert-butylphenyl) phosphite. Examples include fights.

Further, in some cases, the composition of the present invention may contain at least one stabilizer selected from sulfur compounds, ultraviolet absorbers such as benzotriazole compounds, and light stabilizers such as hindered amine compounds. May be. Specific examples of sulfur compounds include pentaerythritol-tetrakis- (β-lauryl-thio-propionate), dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate,
Examples include distearyl-3,3'-thiodipropionate. The thermal stability can be improved by combining such a sulfur compound with the composition of the present invention.

Specific examples of penzotriazole compounds and hindered amine compounds include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and 2
-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2- (2'-hydroxy-
3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'- Hydroxy-3'-tert-
Benzotriazole-based compounds such as butyl-5′-methylphenyl) -5-chlorobenzotriazole and

Bis (2,2,6,6-tetramethyl-4
-Piperidyl) sebacate, dimethyl succinate-1-
(2-hydroxyethyl) -4-hydroxy-2,2
6,6-Tetramethylpiveridine polycondensate, poly [(6
-(1,1,3,3-tetramethylbutyl) imino-
1,3,5-triazine-2,4-diyl] [(2,
2,6,6-Tetramethyl-4-piperidyl) imino]
Hexamethylene [[2,2,6,6-tetramethyl-4
-Piperidyl) imino]] and the like.

By combining such a benzotriazole compound or hindered amine compound with the composition of the present invention, the light resistance thereof can be further improved. The composition of the present invention is obtained by deactivating the block copolymer living solution obtained by the above-mentioned method with a suitable deactivator such as water, alcohol or acid, and then adding the compound represented by the general formula [I] and the After adding a predetermined amount of the phenolic compound of the general formula [II] and / or [III], or by directly adding the whole amount to the solution and uniformly dispersing it, the solvent is removed by steam stripping or a hot roll. You can get it.

Alternatively, a part of the phenolic compound represented by the general formulas [I] and [II] and / or [III] is added to the block copolymer solution, and the solid block copolymer composition is prepared by the above method. After obtaining the above, it can also be obtained by a method of adding and mixing the remaining amount using a kneader such as a roll, a Banbury mixer, a kneader and an extruder. The compounding method of these compounds (stabilizers) is not particularly limited, and methods other than the above may be used, and an appropriate method may be used depending on the situation. The same applies to the method of blending the phosphorus compound, the sulfur compound, the ultraviolet absorber and the light stabilizer.

The block copolymer composition of the present invention can be used by blending it with polystyrene resins such as polystyrene and impact-resistant polystyrene, ABS resins and other engineering resins, and polyethylene, polypropylene and the like. It is also possible to use by blending with the polyolefin resin. Further, the block copolymer composition is preferably used as a hot-melt pressure-sensitive adhesive-like substrate prepared by blending with a tackifier resin or oil, and further blended with straight asphalt, blown asphalt and the like. You can do it.

The block copolymer composition of the present invention may contain a softening agent other than the above, a reinforcing agent, a flame retardant, a foaming agent,
It is also possible to add additives such as a plasticizer and a coloring agent.

[0038]

EXAMPLES In order to explain the present invention in more detail, reference examples, examples and comparative examples will be shown below. These examples will explain the present invention and the excellent effects obtained thereby. However, it does not limit the scope of the present invention.

[0039]

[Reference example]

Manufacture of block copolymers. The block copolymers used in the examples of the present invention were prepared as follows. (Block copolymer A) 4 with jacket and stirrer
After sufficiently purging the 0 L stainless steel reactor with nitrogen, cyclohexane 17,600 g and tetrahydrofuran 5.3
g, 480 g of styrene (referred to as primary styrene) were charged, warm water was passed through the jacket, and the content was set to about 70 ° C. After that, an appropriate amount of n-butyllithium (cyclohexane solution) was added to initiate polymerization of the first styrene.
Five minutes after the first styrene was almost completely polymerized, 2,240 g of butadiene (1,3-butadiene) was added to continue the polymerization, and the butadiene was almost completely polymerized to reach the maximum temperature. After 10 minutes, again styrene (second
(Hereinafter referred to as styrene) was added thereto to continue the polymerization, and after the second styrene was almost completely polymerized, it was kept for 15 minutes to complete the polymerization. Then, 3 mol of water was used per 1 mol of n-butyllithium used. Was added to completely deactivate the active species, and a block copolymer of 30% by weight of styrene having an ABA structure was obtained.

(Block Copolymer B) A 40 L stainless steel reactor equipped with a jacket and a stirrer was sufficiently replaced with nitrogen, then 17,600 g of cyclohexane, 5.3 g of tetrahydrofuran and 960 g of styrene were charged, and warm water was passed through the jacket. The contents were set at about 65 ° C. Thereafter, an appropriate amount of n-butyllithium (cyclohexane solution) was added to initiate the polymerization of styrene. Five minutes after styrene was almost completely polymerized, 2,240 g of butadiene (1,3-butadiene) was added to continue the polymerization, and butadiene was almost completely polymerized to reach the maximum temperature. 1
After 0 minutes, 1/4 equivalent of n-butyllithium used was added to silicon tetrachloride to obtain a block copolymer having a (A-B) _4- Si structure with a styrene content of 30% by weight.

The following stabilizers were used. AO-1: 2,4-bis (n-octylthiomethyl)-
6-methylphenol AO-2: 3,9-bis- {2- [3- (3-tert
-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1-1-dimethylethyl} 2,4
8,10-Tetraoxaspiro [5,5] undecane AO-3: 2-tert-amyl-6- [1- (3,5
-Di-tert-amyl-2-hydroxyphenyl) ethyl] -4-tert-amylphenyl acrylate

AO-4: 2-tert-butyl-6-
(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl) -4-methylphenyl acrylate AO-5: tetrakis- [methylene-3- (3 ', 5'
-Di-tert-butyl-4'-hydroxy-phenyl) propionate] -methane AO-6: 2,6-di-tert-butyl-4-methylphenol AO-7: pentaerythritol-tetrakis- (β-
Lauryl-thio-propionate AO-8: tris (nonylphenyl) phosphite

[0043]

Examples 1 to 5 and Comparative Examples 1 to 6 In the block copolymer A solution shown in Reference Example, the stabilizer (AO-
1 to AO-6) was added in a predetermined amount, and the solvent was removed by steam stripping, dehydrated, and subsequently dried by a hot roll (110 ° C.). After drying, the phosphorus compound AO-8 shown in Table 1 was added on a hot roll to prepare samples of the present invention and comparative examples.

The obtained polymer had MI (G) of 3 g / 10.
Min block copolymer. A heating test, a long-term storage test, and a Labo Plastomill kneading test were performed on these samples. In addition, in the heating test, a part (5 g) of the sample was packed in a cylindrical glass sample bottle having an internal volume of 30 cc,
After covering the upper part with an aluminum foil, the sample was allowed to stand still at 180 ° C. in a gear oven (GPHH-100 type manufactured by Tabai Espec Co., Ltd.), and the color of the sample after heating was observed and the toluene insoluble content was measured.

In the long-term storage test, in order to confirm the discoloration resistance during storage, a tea envelope is filled with about 300 g of the sample, and 1
The color was checked after storage for 2 months. The results of these heating tests and long-term storage tests are shown in Table 1.

It can be seen that the block copolymer of the present invention has a good balance between the discoloration resistance upon heating and the effect of suppressing gel. Further, it is also excellent in resistance to discoloration (yellowing resistance) during long-term storage, and the problem of impairing the product image and the like during long-term storage in a warehouse or the like is solved. The results of the Labo Plastomill kneading test are shown in Table 2.

As shown in Examples 1 and 2 and Comparative Examples 3 and 5, and Examples 3 and 5 and Comparative Example 3, the block copolymers in which the specific phenolic stabilizers limited in the present invention are combined are gels. It can be seen that the suppression effect is high.

[0048]

Example 6 and Comparative Examples 7 and 8 and Example 7 and Comparative Examples 9 and 1
0 in the block copolymer B solution shown in the example.
AO-1 and AO-2 shown in (4) were added in predetermined amounts, and the solvent was removed by steam stripping. After dehydration, the product was subsequently dried with a hot roll (110 ° C.).
After drying, the remaining stabilizer AO-shown in Table 3 on a hot roll.
4, AO-6 and AO-8 were each added in predetermined amounts to prepare block copolymer samples of the present invention and comparative examples. The obtained polymer was a block copolymer having MI (G) of 8 g / 10 min.

A Lab-Plastomill kneading test was performed on these samples. The gelation peak time obtained as a result is shown in Table 3. It can be seen that the block copolymer in which the phenolic stabilizer specified in the present invention is combined has a high effect of suppressing gelation.

[0050]

[Table 1]

[0051]

[Table 1 '] (Note 1) The compounding amount of the stabilizer shows the compounding ratio (parts by weight) with respect to 100 parts by weight of the block copolymer. (Note 2) 1 Judgment after heating ◎ ... Colorless (white) or almost no discoloration. ◯ ... Light yellow to yellow, Δ ... Light brown, × ... Brown to dark brown 2 Toluene insoluble matter (wt%) 1 g of the composition after heating is dissolved in 100 g of toluene, and 1
The residue of the wire mesh was rubbed with a 00 mesh wire mesh, and the residue was dried and then produced as a toluene insoluble matter.

[0052]

[Table 2]

(Note 3) Labo Plastomill kneading conditions Kneading machine: LPM-2500-200 (Mixer-B-75) manufactured by Toyo Seiki Co., Ltd. 1 Condition I Sample amount: 50 g Kneading condition: 190 rpm, 30 rpm after preheating ,
Measured by increasing the rotation speed to 120 rpm. 2 Condition II Kneading was performed under the nitrogen atmosphere in the same manner as in Condition 1.

[0054]

[Table 3]

[0055]

EFFECT OF THE INVENTION The block copolymer composition of the present invention is excellent in discoloration resistance during long-term storage and stability of physical properties under high temperature heating, and is highly effective in suppressing generation of gel-like substances. Taking advantage of these characteristics, various applications such as adhesive materials, thermoplastic resin modifiers, footwear materials, asphalt modifiers, wire cable materials, electrical products, automobile parts, industrial parts, It can be used for materials such as household items and toys.

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[Procedure amendment]

[Submission date] March 15, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Chemical 1] (In the formula, R ₁ and R ₃ are —CH ₂ —S—R ₅ , and R 1
5 represents an alkyl group having 1 to 18 carbon atoms. R ₂ represents a hydrogen atom or a methyl group. R ₄ represents an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 12 carbon atoms. (C) At least one stabilizer selected from phenolic compounds represented by the following general formulas [II] and [III],
... 0.05 to 2.0 parts by weight

[Chemical 2] (In the above formula, R ₆ is an alkyl group having 1 to 18 carbon atoms, R ₇ is a tert-butyl group, a tert-amyl group, or a cyclohexyl group, and R ₈ , R ₉ , and R
₁₀ and R ₁₁ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. And a block copolymer composition having excellent thermal stability and resistance to discoloration during long-term storage.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

[0011]

[Chemical 2]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

The substituent R ₄ having 1 to 8 carbon atoms is a methyl group, an ethyl group, an n-butyl group, a sec-butyl group,
A tert-butyl group and the like can be mentioned, but a methyl group or a tert-butyl group is preferable. 5 carbon atoms
Examples of the substituent R ₄ as the cycloalkyl group of 12 include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group , a cyclooxyl group and the like, but a cyclohexyl group is preferable. Specific examples of the phenolic compound represented by the general formula [I] include 2,4-bis (n-octylthiomethyl) -6-methylphenol and 2,4-bis (n-dodecylthiomethyl) -6-. Methylphenol,
2,4-bis (phenylthiomethyl) -3-methyl-6
-Tert-butylphenol and the like can be mentioned. Most preferably 2,4-bis (n-octylthiomethyl)
It is -6-methylphenol.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

Specific examples of the phenolic compounds represented by the general formulas [II] and [III] include 2-tert-amyl-6- [1- (3,5-di-tert-amyl-2.
-Hydroxyphenyl) ethyl] -4-tert-amylphenyl acrylate, 2-tert-butyl-6-
(3'-tert-butyl-5'-methyl-2'- hydr
Roxybenzyl ) -4-methylphenyl acrylate,
2,4-di-tert-butyl-6- (3 ', 5'-di-tert-butyl-2'-hydroxybenzyl) phenyl acrylate, 2,2'-ethylidene-4,6-di-tert-butylphenol -(4 ', 6'-di-t
ert-butyl-phenyl acrylate), 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,
1-di-methylethyl} 2,4,8,10-tetraoxaspiro [5,5] undecane and the like can be mentioned.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction content]

The block copolymer composition of the present invention can be used by blending it with polystyrene resins such as polystyrene and impact-resistant polystyrene, ABS resins and other engineering resins, and polyethylene, polypropylene and the like. It is also possible to use by blending with the polyolefin resin. Further, the block copolymer composition, even as a hot melt adhesive base material formed by blending a tackifier resin and oil, further, that the straight asphalt, be blended with blown asphalt or the like suitably used There kill in.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction content]

[0043]

Examples 1 to 5 and Comparative Examples 1 to 6 In the block copolymer A solution shown in Reference Example, the stabilizer (AO-
1 to AO-6) was added in a predetermined amount, and the solvent was removed by steam stripping, dehydrated, and subsequently dried by a hot roll (110 ° C.). After drying, the phosphorus compound AO-8 shown in Table 1 was added on a hot roll to prepare samples of the present invention and comparative examples.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

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[0051]

[Table 1 '] (Note 1) The compounding amount of the stabilizer shows the compounding ratio (parts by weight) with respect to 100 parts by weight of the block copolymer. (Note 2) 1 Judgment after heating ◎ ... Colorless (white) or almost no discoloration. ○ ・ ・ ・ Light yellow to yellow, △ ・ ・ ・ Light brown, × ・ ・ ・ Brown to dark brown 2 Toluene insoluble matter (wt%) 1 g of the composition after heating is dissolved in 100 g of toluene, and 1
It was rubbed with a 00 mesh wire mesh and the residue of the wire mesh was dried, and then calculated as a toluene insoluble content.

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[Table 2]

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(Note 3) Labo Plastomill kneading conditions Kneading machine: LPM-2500-200 (Mixer-B-75) manufactured by Toyo Seiki Co., Ltd. 1 Condition I Sample amount: 50 g Kneading conditions: 190 rpm, 30 minutes after preheating ,
Measured by increasing the rotation speed to 120 rpm. 2 Condition II Kneading was carried out in a nitrogen atmosphere in the same manner as in Condition 1. Gas flow rate: Nitrogen 1 L / min

Claims (1)

[Claims] 1. A polymer having (a) at least one polymer segment mainly containing a monoalkenyl aromatic compound and at least one polymer segment mainly containing a conjugated diene,
A block copolymer having a monoalkenyl aromatic compound content of 5 to 95% by weight, or a mixture of the block copolymer and a thermoplastic resin and / or a rubber-like polymer,
... 100 parts by weight (b) Stabilizer which is a phenolic compound represented by the following general formula: 0.005-0.2 polymerized part (In the formula, R ₁ and R ₃ are —CH ₂ —S—R ₅ ;
₅ represents an alkyl group having 1 to 18 carbon atoms. R ₂ represents a hydrogen atom or a methyl group. R ₄ represents an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 12 carbon atoms. (C) At least one stabilizer selected from phenolic compounds represented by the following general formulas [II] and [III],
... 0.05 to 2.0 parts by weight (In the above formula, R ₆ is an alkyl group having 1 to 18 carbon atoms, R ₇ is a tert-butyl group, a tert-amyl group or a cyclohexyl group, and R ₈ , R ₉ , R ₁₀
And R ₁₁ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. And a block copolymer composition having excellent thermal stability and resistance to discoloration during long-term storage.