JPS63343A - Thermoplastic elastomer composition for footwear - Google Patents

Abstract

PURPOSE:To obtain the title compsn. having improved physical properties without lowering flow characteristics, by blending a specified block copolymer having modified terminals with process oil and an inorg. filler. CONSTITUTION:A compsn. consists of 100pts.wt. thermoplastic elastomer (A) which is a block copolymer having modified terminals obtd. by reacting alkali metals attached to the terminals of the polymer chain of a block copolymer consisting of a polymer block mainly composed of at least two arom. vinyl compds. and a polymer block mainly composed of a conjugated diene with a compd. selected from the group consisting of compds. (i) having -C(X)- and =N-R1, groups (wherein X is O or S; and R1 is a member selected from the group consisting of H, a 1-20C alkyl group, etc.) and compds. (ii) having -N=C=X group (wherein X is O or S), 10-200pts.wt. process oil (B) having a viscosity-gravity constant of not higher than 0.900, 10-150pts.wt. inorg. filler (C) and 0-120pts.wt. polystyrene (D).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to thermoplastic outer body compositions for footwear that have improved physical properties without reducing flowability.

More specifically, it consists of a terminal-modified block copolymer obtained by reacting a block copolymer consisting of a conjugated diene with an alkali metal atom bonded to the end of the polymer chain and a vinyl aromatic compound with a specific nitrogen-containing compound. The present invention relates to a thermoplastic elastomer composition for footwear that has improved tensile strength, elongation 1 impact resilience, abrasion resistance, oil resistance, and bending resistance without reducing fluidity.

[Prior Art] Various materials have been used for shoe soles. Natural rubber and SBR are rubbers with well-balanced physical properties, but require a vulcanization process and are expensive. Further, polyurethane rubber having excellent physical properties can be used unvulcanized, but it is more expensive. On the other hand, although soft vinyl chloride resin is inexpensive, it has poor physical properties such as thermal stability, low-temperature properties, and slip resistance. As described above, conventional materials have problems in the balance between economy and performance.

In contrast, styrene-butadiene blow.

SB-based copolymer rubber (hereinafter abbreviated as SB-based TR) is an excellent thermoplastic elastomer free from these drawbacks. Thermoplastic elastomers are woody different from the rubbers commonly used in the rubber industry and exhibit good rubbery properties without the need for a vulcanization process. That is, it has the characteristics of having the same fluidity as general thermoplastic resins at high temperatures, being easily moldable using a normal plastic molding machine, and exhibiting good rubber-like properties when returned to room temperature.

However, SO-based TR has significantly inferior fluidity compared to ordinary thermoplastic resins, and is also susceptible to thermal deterioration at high temperatures, making it difficult to improve fluidity by increasing the processing temperature during molding. Therefore, process oil is generally added to improve fluidity. However, when only process oil is added, the fluidity is improved, but the hardness is low, and in addition, the tensile strength is significantly reduced. Therefore, in order to maintain both fluidity and physical properties at the same time, a method of blending polystyrene resin, inorganic fillers, etc. in addition to process oil is generally used, but although this improves fluidity and hardness, The decrease in tensile strength is not sufficiently improved.

Recently, there has also been a desire to improve the rebound resilience, abrasion resistance, and bending resistance of rubber for soles from both comfort and practicality, but conventional rubber for soles using SB type TR is insufficient. is not satisfactory.

In addition, since SB-based TR is not chemically crosslinked like vulcanized rubber, it has extremely poor oiliness, and when used as rubber for shoe soles, it also has the drawback of significant deterioration and wear of the soles.

Many improvements have been attempted to address these problems.

In Japanese Patent Application Laid-open No. Sho GO-170850, the SB type TR is 1.
It is disclosed that a specific composition made of 2-polybutadiene or the like can provide a composition with excellent hardness, fluidity, molded product appearance, bending resistance, and ozone resistance, but the improvement effect is It is incomparable, and also has rebound resilience, oil resistance, #
The effect of improving abrasion properties is not disclosed. Japanese Patent Publication No. 59-22
Publication No. 3744 discloses that oil resistance can be improved by blending an acrylic copolymer with an SR type TR, but this has the problem of low tensile strength and low elongation F. Furthermore, in US Pat. No. 4,409,357, fluidity is improved by using a polyvinyl aromatic compound as a coupling agent to create a branched SB-based TR and using a block copolymer in which a polar group is bonded to the branch point portion. However, the improvement effect is insufficient, and the improvement effect on tensile strength, repulsion resistance, etc. is not disclosed.

[Problems to be Solved by the Invention] In view of the point L, the present invention provides a footwear product that simultaneously satisfies tensile strength, elongation, impact resilience, abrasion resistance, oil resistance, and bending resistance without reducing fluidity. It is an object of the present invention to provide a thermoplastic outer body composition.

[Means and effects for solving the problems] As a result of intensive research conducted by the present inventors in order to solve the above problems, surprisingly, an alkali metal atom was found at the end of the polymer chain. The present invention was completed based on the discovery that the object of the present invention can be achieved by using a terminal-modified block copolymer obtained by reacting a blown copolymer with a specific nitrogen-containing compound.

That is, the present invention provides a block copolymer comprising (a) a polymer block mainly composed of at least two vinyl aromatic compounds and at least one polymer block mainly composed of a conjugated diene; A compound having at least one atom at the end of the polymer chain (in the formula, (representing selected substituents).

i) A compound having at least one -N=C=X group in the molecule (wherein X represents an oxygen atom or a sulfur atom).

100 parts by weight of a thermoplastic elastomer which is a terminally modified block copolymer obtained by reacting a nitrogen-containing compound selected from the group consisting of (b) 10 to 10 parts of a process oil having a viscosity specific gravity constant of 0.900 or less (c) 10 to 150 parts by weight of an inorganic filler; and (d) 0 to 120 parts by weight of a polystyrene resin.

The present invention will be explained in detail below.

The thermoplastic outer body used in the present invention has at least one polymer chain terminal obtained by block copolymerizing a conjugated diene and a vinyl aromatic compound using an alkali metal or an organic alkali metal compound as a polymerization initiator. It is obtained by reacting a block copolymer with bonded alkali metal atoms with a specific nitrogen-containing compound.

In the present invention, the above composition using a terminal-modified block copolymer obtained by reacting a block copolymer having an alkali metal atom bonded to the end of the polymer chain with a specific nitrogen-containing compound, Since the residue of the nitrogen-containing compound bonded to the chain end has a polar moiety, when an inorganic filler is blended, it has a strong affinity for the surface, and the residue of the nitrogen-containing compound does not bond to the block coexistence. Tensile strength, rebound resistance, etc. are improved compared to compositions using polymers. However, at high temperatures, this effect is weakened due to thermal movement, and fluidity during molding and processing is not impaired.

Additionally, the effects of nitrogen-containing compound residues bonded to the ends of the block copolymer chain are greater in terms of tensile strength, elongation, oil resistance, impact resilience, etc. than when they are bonded to the center of the polymer chain. , excellent bending resistance.

These things can only be achieved by bonding the residue of a specific nitrogen-containing compound to the end of the polymer chain.

Any known method may be used for producing the block copolymer comprising a conjugated diene having an alkali metal atom bonded to at least one polymer chain end and a vinyl aromatic compound used in the present invention, such as Japanese Patent Publication No. 3B-19288.
Publication No. 48-2423, Special Publication No. 4B-4
Examples include methods described in Japanese Patent Publication No. 108, Japanese Patent Publication No. 49-3H57, and the like. That is, in an inert hydrocarbon solvent,
This is a method of block copolymerizing a conjugated diene and a vinyl aromatic compound using an organic lithium compound or the like as an anionic polymerization initiator.

The manner of bonding of blocks in the block copolymer used in the present invention is represented by the following general formula as an example, but is not limited thereto.

General formula % Formula % (In the formula, A is a polymer block mainly composed of a vinyl aromatic compound, B is a polymer block mainly composed of a conjugated diene,
R is a polyfunctional organic alkali metal initiator residue, n is an integer of 2 or more) A and B may change their structures to the extent that their physical and chemical properties are not essentially impaired.

For example, a block A mainly composed of vinyl aromatic compounds may have a structure in which conjugated dienes are arranged almost randomly, and a block B mainly composed of conjugated dienes may have a structure in which the vinyl aromatic compounds are arranged almost randomly. 1 to 1! It may be a structure in which E is placed. In addition, block A may be a complete block or a tapered block.

The block copolymer used in the present invention may be any mixture of block copolymers represented by the above general formula.

The vinyl aromatic compound content in the block copolymer used in the invention is preferably in the range from 10 to 60% by weight, particularly preferably in the range from 20 to 50% by weight. 1
If it is less than 0% by weight, the tensile strength will be insufficient, which is undesirable.
If it exceeds 60% by weight, the rubber elasticity will be significantly reduced, which is not preferable.

Further, the polymerization average molecular weight of the block copolymer determined by gel permeation chromatography in terms of standard polystyrene is preferably in the range of 30,000 to 500,000. When is polybutadiene, the microstructure is
Preferably, the 1,2-vinyl content is in the range 8-45%, which can be determined using an infrared spectrophotometer using the method of Hampton (Analytica ICell,
21.943 (1943)).

The vinyl aromatic compound used in the present invention includes:

Examples include styrene, p-methylstyrene, α-methylstyrene, p-tart-butylstyrene, etc., but styrene and p-methylstyrene are preferred; these may be used alone or in combination of two or more. May be used.

Examples of the conjugated diene used in the present invention include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3
-dimethyl-1,3-butadiene etc., but l
, 3-butadiene and isoprene are preferred. These may be used alone or in combination of two or more.

Examples of the polymerization initiator used in the present invention include alkali metals such as lithium, sodium, and potassium, and organic alkali metal compounds such as organic lithium compounds, organic sodium compounds, and organic potassium compounds. Particularly preferred polymerization initiators include organic monolithium compounds, organic dilithium compounds, organic polylithium compounds, etc. Specifically, n-butyllithium, 5ec-butyllithium, ethyllithium, n-propyllithium, isopropyllithium , n-decyllithium, phenyllithium, 2-
Naphthyl lithium, hexamethylene dilithium, butadienyl dilithium, imprenyl dilithium, 1.2-
dilithio-1,2-diphenylmethane, 1.3.5-)
Examples include lilithiobenzene. These may be used alone or in a mixture of two or more.

Further, as the organic polylithium compound used in the present invention, there is also used one that can be substantially converted into an organic polylithium compound by reacting the above-mentioned organic monolithium compound with another compound. For example, the reaction product of an organic monolithium compound and a polyvinyl aromatic compound (
Japanese Patent Publication No. 55-8652), a reaction product obtained by reacting an organic monolithium compound with a conjugated diene and/or a monovinyl aromatic compound, and then reacting a polyvinyl aromatic compound, or an organic monolithium compound, a conjugated diene, and/or a reaction product obtained by simultaneously reacting a monovinyl aromatic compound and the king of polyvinyl compounds (West German Patent No. 2003384, etc.).

As the inert hydrocarbon solvent, cyclohexane, n-hexane, and benzene are preferably used, but in addition, aliphatic hydrocarbons such as butane, pentane, heptane, and octane,
Alicyclic hydrocarbons such as cyclopentane and methylcyclohexane, and aromatic hydrocarbons such as toluene and xylene can be used.

Furthermore, when producing the block copolymer, a small amount of a polar compound such as ether or tertiary amine may be coexisting in the inert solvent for the purpose of adjusting the microstructure of the conjugated diene portion.

The specific nitrogen-containing compound used in the present invention is a compound having at least one (in the formula, represents a substituent selected from an aryl group and an alkenyl group).

ii) Compounds having at least one -N=C=X group in the molecule (wherein X represents an oxygen atom or a sulfur atom).

A nitrogen-containing compound selected from the group consisting of amides, lactams, imides, urea compounds, carbamate esters, amine group-containing aldehydes, amino group-containing ketones, amide group-containing esters, amino group-containing acid chlorides, incyanates. Compounds and compounds in which the oxygen atom in these above compounds is replaced with a sulfur atom can be mentioned. Among these, preferred are amides, lactams, urea compounds, and incyanate compounds, and particularly preferred are amides, lactams, and urea compounds.

Specific examples include the following compounds.

Amides include formamide, acetamide, propiamide, benzamide, methacrylamide, 2-pyridylamide, 4-pyridylamide, nicotinamide, acrylamide, N,N-dimethyl-p-aminobenzamide, p-aminobenzamide, N,N- Dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide,
N,N-dimethylpropioamide, N,N-diethylpropioamide, N,N-dimethylbenzamide, N,
N-diethylbenzamide, N,N-dimethyl-2-pyridylamide, N,N-dimethyl-4-pyridylamide, N,N-diethyl-4-pyridylamide, N,N-
Dimethylnicotinamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylmethacrylamide, N-phenylformamide, N-phenylacetamide, N-phenylpropioamide, N-methyl-
N-phenylacetamide, N,N-dimethyl (N',
N'-p-dimethylamino)benzamide, N,N-diethyl(N',N'-p-dimethylamino)benzamide, N,N-dimethyl(N',N'-p-diethylamino)benzamide, N,N -diethyl (S/, S/-p
-diethylamino)benzamide, etc.

Lactams include ε-caprolactam, N-methyl-
e-caprolactam, δ-octaherolactam, N-methyl-δ-valerolactam, 2-pyrrolidone, N-methyl-
Examples include 2-pyrrolidone and N-acetyl-ε-caprolactam.

Examples of the imide include succinimide, N-methylsuccinimide, N-phenylsuccimide, maleimide, N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, phthalimide, N-methylphthalimide, and N-phenylphthalimide.

Examples of urea compounds include urea, N,N'-dimethylurea,
N,N'-diethylurea, N,N'-diphenylurea, N,N,N',N'-tetramethylurea, N,N,N
',N'-tetraethylurea, N,N-dimethyl-N'
, N'-diethylurea, N, N-dimethyl-N', N
'-Diphenylurea, N,N'-dimethylethyleneurea, N,N'-diethylethyleneurea, N,N'-dipropylethyleneurea, N-ethyl-N'-methylethyleneurea, N-methyl-N' -Phenylethylene urea, N
-Ethyl-N'-phenylethyleneurea, N,N'-diphenylethyleneurea, N,N'-dimethylpropyleneurea, N,N'-diethylpropyleneurea, N,N'
, N''-trimethylisocyanuric acid and the like.

Examples of ertel carbamate include methyl carbamate,
Methyl N,N-dimethylcarbamate, N,N-diethylcarbamate, Ethyl N,N-dimethylcarbamate, Ethyl N,N-diethylcarbamate, Phenyl carbamate, N
, N-dimethylcarbamine-phenyl, and phenyl N,N-diethylcarbamate.

It represents a substituent selected from the above amide, lactam, imide, ureated group, cycloalkyl group, aryl group, and alkenyl group. ) in the same molecule include amino group-containing aldehydes, amine group-containing ketones, amino group-containing esters, and amine group-containing acid chlorides. Specific examples include 6-N,N-dimethyl Methyl aminocaproate, 8-N,N-dimethylaminocaproic acid chloride, p-7 minobenzaldehyde, p-aminoaminobenzoic acid chloride, methyl p-aminobenzoate, p-
dimethylaminobenzaldehyde, p-dimethylaminobenzoic acid chloride, methyl p-dimethylaminobenzoate,
p-Dimethylaminoacetophenone, p-dimethylaminobenzophenone, p-diethylaminobenzaldehyde, p-diethylaminobenzoic acid chloride, ρ-methyl diethylaminobenzoate, p-diethylaminoacetophenone, P-diethylaminobenzophenone, 4.4'~
Examples include bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, and 4,4'-diaminobenzophenone.

Incyanate compounds include methyl isocyanate, ethyl isocyanate, propyl incyanate, η
-butyl isocyanate, cyclohexyl isocyanate, η-hexyl incyanate, allyl inocyanate, phenyl isocyanate, naphthyl isocyanate, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate,
Examples include naphthylene-1,5-diisocyanate, hexamethylene diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate, lysine diisocyanate, and inpropylidene bis(4-cyclohexyl isocyanate). .

Also included are compounds in which the oxygen atom in these above compounds is replaced with a sulfur atom.

It is preferable that the terminal-modified block copolymer obtained by the above method has residues of the nitrogen-containing compound bonded to all polymer chain ends. The proportion of bonded residues changes depending on the conditions, and a coupling reaction may occur partially. However, in order to achieve the object of the present invention, it is necessary that the proportion of the polymer to which the residue is bonded to the terminal in the total polymer is 10% by weight or more, preferably 20% by weight or more. The content is particularly preferably 30% by weight or more. If it is less than 10% by weight, the targeted effect of improving physical properties cannot be obtained.

The amount of the nitrogen-containing compound used in the present invention is 0.01 mol to 10 mol per mol of the alkali metal in the polymerization initiator used when polymerizing the block copolymer,
Preferably it is 0.2 to 2 mol.

In order to obtain a terminally modified block copolymer in the present invention, when a block copolymer having an alkali metal atom bonded to at least one polymer chain terminal is reacted with a specific nitrogen-containing compound, the polymer chain terminal is conjugated. A structure in which the alkali metal element t is bonded to a diene unit is preferable because the proportion of bonding of the residue of the sulfur-containing compound becomes higher and the effect of improving physical properties is greater.

Further, depending on the case, the alkali metal moiety of the obtained terminal-modified blown copolymer can be further replaced with hydrogen using alcohol, water, mineral acid, carboxylic acid, or the like.

After the reaction is completed, the block copolymer with the terminal modifier residues bound thereto is recovered from the reaction solution using a conventional separation method such as adding a coagulant such as methanol, stripping with steam, or using a hot roll. Ru.

The process oil constituting the composition of the present invention is a process oil obtained by highly refining petroleum fractionation products by methods well known in the art such as solvent reforming and hydrogenation reforming, and has a viscosity specific gravity constant of It is 0.900 or less.

Here, the viscosity specific gravity constant (Viscosity Gravi
tyConstant, hereinafter abbreviated as FV, G, C. )
However, Specific gravity of oil under G=80 V+ = 210'F Viscosity of smelling oil (SOS)
It is given by

Normally, process oils are classified into various types depending on their components, but if you use V, G11l:, V, G, C
: 0.790-0.819 is paraffinic, 0.820-0.849 is quite paraffinic, 0.850-0.899 is naphthenic, 0.9
00~Q, 94S is quite aromatic, 0.950
~0.999 is aromatic, 1.000~1.04
A value of 9 is classified as extremely aromatic, and a value of 1.050 or higher is classified as extremely aromatic.

The process oil used in the present invention is V, G,
C, is selected from all process oils with a value of 0.900 or less. When V, G, and C are larger than 0.900.

Since it is rich in aromatic components, the tensile strength is significantly lowered, which is undesirable. More preferable ranges of V, G, and C are as follows:
It is 0.820~o, soo.

The amount of the process oil added is 10 to 200 parts by weight, preferably 20 to 150 parts by weight, per 100 parts by weight of the block copolymer.
Parts by weight. If the amount added is less than 10 parts by weight, the fluidity improvement effect, which is the original purpose of blending process oil, will not be sufficient, and if it exceeds 200 parts by weight, the tensile strength will drop significantly, which is undesirable.

Inorganic fillers constituting the composition of the present invention include heavy or light calcium carbonate, magnesium carbonate, barium carbonate, silica, aluminum hydroxide, magnesium oxide,
Examples include titanium dioxide, silicates, and clay. Each can be used alone or in combination of two or more.For application to the composition of the present invention, calcium carbonate and titanium dioxide are preferred, and the amount used is 10 to 150 parts by weight per 100 parts by weight of the block copolymer. , preferably in the range of 10-100 parts by weight; if the amount added is less than 10 parts by weight,
It is not substantially useful for improving oil absorption and rigidity, and if it exceeds 150 parts by weight, the tensile strength and fluidity of the composition will be impaired, which is not preferable.

The composition of the present invention may contain a polystyrene resin if necessary. Polystyrene resin is a resin containing 80% by weight or more of styrene or styrene derivatives, and generally includes resins called general-purpose polystyrene, high-impact polystyrene, poly-α-methylstyrene, poly-p-methylstyrene, etc. 6 Polystyrene is preferably used in the present invention. In addition, these may be used alone or in combination of two or more, but the total amount is 0 to 120 parts by weight based on 100 parts by weight of the block copolymer.
The amount is preferably in the range of 10 to 90 parts by weight; if the amount exceeds 120 parts by weight, the rubber elasticity of the composition will significantly decrease, which is not preferred.

The thermoplastic elastomer composition for footwear of the present invention comprises the above-mentioned (a)
, contains components (b) and (c) as essential components, and contains component (d) as necessary, but in addition, as necessary, anti-aging agents, ultraviolet absorbers, antistatic agents, flame retardants, Fillers, reinforcing agents, blowing agents, colorants, lubricants, pigments, etc. can be included.

The composition of the present invention is obtained by mixing each component in a kneading machine such as a roll, a Banbury mixer, or a kneader 1 extruder.

The temperature during kneading is 130 to 170°C for rolls;
A suitable temperature is 130 to 180°C for a Banbury mixer, and 150 to 200°C for an extruder. These can also be pelletized using a sheet pelletizer, crusher, or extruder.

The composition thus obtained is flexible and has excellent elasticity,
and improves tensile strength, elongation, and rebound without impairing fluidity.
Since it has improved properties such as hardness, abrasion resistance, oil resistance, and bending resistance, it can be used as a material for footwear such as unit soles, direct soles, foamed direct soles, and foamed sandals.

[Examples Examples 1 to 11. Comparative Examples 1 to 3 Internal volume 10! ; After washing and dry-blasting a stainless steel reactor of L, and thoroughly purging with dry nitrogen, cyclohexane 5
000 g, styrene 200 g, and tetrahydrofuran 1.25 g were charged, and the contents were heated while stirring until the temperature of the contents reached 70°C. As soon as the temperature reached 70°C, heating was stopped, and n-butyllithium ( Polymerization of styrene was started by adding 15 mmol of cyclohexane solution. After 15 minutes, when the 2-ethylene monomer was almost completely consumed, 570 g of 1,3-butadiene was added. 1.
30 minutes after the polymerization of 3-butadiene was completed, the 200
g of styrene was added. After 15 minutes, when the 2-ethylene monomer was almost completely consumed, 30 g of 1-ethylene monomer was added again.
．． After adding 3-butadiene, 1,3 was almost completely converted in 10 minutes.
- Butadiene has been consumed. After the polymerization reaction was completed, 15 mmol of the compound shown in Table 2 was added, and after stirring for 20 minutes, 5 g of methanol was added, and stirring was continued for an additional 5 minutes.

In Comparative Example 1, after the polymerization reaction was completed, 5 g of methanol was added and stirred for 5 minutes. In Comparative Example 2, 5g of methanol was added after the polymerization reaction was completed, and after stirring for 5 minutes, N
, 15 mmol of N-dimethylacetamide were added.

In Comparative Example 3, after the polymerization reaction was completed, 15 mmol of ethylene oxide was added and stirred for 20 minutes, and then 5 g of methanol was added and stirred for an additional 5 minutes.

The polymer solution thus obtained was taken out from the reactor and
, 6-tert-butyl-4-methylphenol and tris(nonylphenyl)phosphite were added in an amount of 0.5 parts by weight each per 100 parts by weight of the block copolymer and dried with a heated roll to obtain a polymer. .

The thus obtained polymer was kneaded on a roll according to the formulation A shown in Table 1 to obtain a compound.

Table-1 Note 1) Diana Process MS-100 Note 2 manufactured by Idemitsu Kosan
) Shiroishi Kogyo Co., Ltd., red dot mark, slight calcium carbonate Note 3) Asahi Kasei Co., Ltd., Styron θ79 The total styrene content in the obtained block copolymer and the physical property measurement results of the blend obtained by blending with blending recipe A are shown in the table below.
Shown in 2.

Note 4) Measured using an ultraviolet spectrophotometer (Hitachi UV-200).

Note 5) Measurements were performed according to the following method.

Melt Flow Index ASTM 01238 E Condition Dunlop Resilience (25℃) B5903 Abrasion Resistance
Abrasion resistance Akron abrasion (index) Demarcia bending JIS
K-6301 tensile test JIS K-8301 Note 6) # Oil test uses a JIS No. 3 dumbbell with a thickness of 2ffflflI as a test piece, immerses the test piece in JIS No. 3 oil, and holds it at 25 ° C for 50 hours. Afterward, the weight increase rate was measured and a tensile test was conducted.

The physical property retention rate 1 weight increase rate was determined by the following formula.

Weight increase rate (2) = From the results in Table 2, the Mi composition containing the terminal-modified block polymer of the present invention has improved tensile strength, elongation, impact resilience, itching resistance, It can be seen that the oil resistance and bending resistance are significantly improved.

Examples 12-22. Comparative Examples 4-6 In the same manner as Examples 1-11, cyclohexane 5000
g, styrene 150g, tetrahydrofuran 1.5g
was charged into a reactor and heated to 70°C while stirring.

20 mmol of n-butyllithium was added to initiate styrene polymerization. After 15 minutes, when the styrene monomer was almost completely consumed, 700 g of 1,3-butadiene was added, and after 40 minutes, when 1,3-butadiene was almost completely consumed, 150 g of styrene was added, and the mixture was heated for 15 minutes. Afterwards, the styrene monomer was almost completely consumed. After completion of polymerization, Table-3
After adding 20 mmol of the compound shown in and continuing stirring for 20 minutes, 5 g of methanol was added and the mixture was stirred for another 5 minutes.
Continued stirring. However, in Comparative Examples 4 and 5, after the polymerization was completed, 5 g of methanol was added and stirred for 5 minutes. In Comparative Example 5, 20 mmol of N-methyl-ε-caprolactam was further added thereafter.

In Comparative Example 6, in the same manner as in Examples 1 to 11, 5000 g of cyclohexane, 300 g of styrene, and 1.5 g of tetrahydrofuran were charged into a reactor, and while stirring,
The temperature was raised to 0°C, and 40 mmol of n-butyllithium was added to start polymerization of styrene. After 15 minutes, when the styrene monomer was almost completely consumed, 700 g of 1,3-butadiene was added, and after 30 minutes, when the 1,3-butadiene was almost completely consumed, the temperature of the reactor contents was increased again. 70
°C, 60 mmol of m-divinylbenzene was added, and stirring was continued for 8 hours while maintaining the temperature at 70 °C. After 8 hours, 40 mmol of N,N-dimethylformamide was added and stirred for 20 minutes, then 5 g of methanol was added and stirring was continued for an additional 5 minutes.

The polymer was recovered in the same manner as in Examples 1 to 11, and kneaded on a roll according to the formulation B in Table 1 to obtain a compound.

Table 3 shows the total styrene content in the block copolymer and the physical properties of the blend, which were measured in the same manner as in Examples 1 to 11.
Shown below.

The results in Table 3 also show that the composition containing the terminal-modified block copolymer of the present invention can improve tensile strength, elongation, impact resilience, and l1lF# abrasion properties without reducing fluidity.

It can be seen that the composition has significantly improved oil resistance and bending resistance.

[Effects of the Invention End 1'11 The thermoplastic elastomer composition for footwear is flexible and has excellent rubber properties, and has excellent tensile strength, elongation, impact resilience, abrasion resistance, and oil resistance without impairing fluidity. Since it has improved bending resistance, it can be used as a material for footwear such as unit soles, tie-left soles, foamed direct soles, and foamed sandals.

Claims (1)

[Scope of Claims] (a) A block copolymer consisting of at least two polymer blocks mainly composed of vinyl aromatic compounds and at least one polymer block mainly composed of a conjugated diene; A block copolymer with an alkali metal atom bonded to the end of the polymer chain;
Compounds each having at least one N-R_1 group (
In the formula, X represents an oxygen atom or a sulfur atom, and R_1 represents hydrogen or a substituent selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an aryl group, and an alkenyl group). ii) Compounds having at least one -N=C=X group in the molecule (wherein X represents an oxygen atom or a sulfur atom). 100 parts by weight of a thermoplastic elastomer which is a terminally modified block copolymer obtained by reacting a nitrogen-containing compound selected from the group consisting of (b) 10 to 10 parts of a process oil having a viscosity specific gravity constant of 0.900 or less 200 parts by weight of a thermoplastic elastomer composition for footwear, comprising: (c) 16 to 150 parts by weight of an inorganic filler; and (d) 0 to 120 parts by weight of a polystyrene resin.