JP3366434B2 - Thermoplastic resin composition and film comprising the same - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition comprising a specific thermoplastic polyurethane and a specific aromatic vinyl compound-conjugated diene block copolymer, and a film comprising the resin composition. The thermoplastic resin composition of the present invention is excellent in elastic recovery, strength and elongation, heat resistance, flexibility and film forming property. The film of the present invention effectively exhibits the features of the resin composition and is useful as a stretchable film.

[0002]

2. Description of the Related Art Thermoplastic polyurethanes have elastic recoverability,
Although it has excellent performance in terms of strength and flexibility, it is a relatively expensive resin. On the other hand, polyethylene, polypropylene, ethylene / vinyl acetate copolymer, ethylene /
Polyolefin resins such as methyl acrylate copolymer and aromatic vinyl compound resins such as polystyrene are cheaper than thermoplastic polyurethane. Therefore, in order to inexpensively obtain a thermoplastic resin material that retains the excellent properties of the thermoplastic polyurethane, it has been attempted to blend the thermoplastic polyurethane with a polyolefin resin or an aromatic vinyl compound resin.

However, the thermoplastic polyurethane is incompatible with the polyolefin resin and the aromatic vinyl compound resin, and when they are simply blended, the dispersed state is not good. Probably because of this, when a resin composition of thermoplastic polyurethane and a polyolefin resin or an aromatic vinyl compound resin is subjected to film forming, there is a problem that film forming stability is low and it is difficult to form a thin film. This difficulty in forming a thin film becomes particularly remarkable when the thermoplastic polyurethane is flexible. Further, even in a film obtained from a resin composition of thermoplastic polyurethane and a polyolefin resin or an aromatic vinyl compound resin, there is a problem that performance such as elastic recovery, strength and flexibility becomes insufficient.

[0004]

SUMMARY OF THE INVENTION One of the objects of the present invention consists of a thermoplastic polyurethane and another thermoplastic resin, and retains the excellent elastic recovery, heat resistance and high elongation of the thermoplastic polyurethane. In addition, it is to provide a thermoplastic resin composition which has high film-forming stability and can be formed into a thin film. Another object of the present invention is to provide a film made of thermoplastic polyurethane and another thermoplastic resin and having excellent elastic recovery, heat resistance, strength and elongation, and flexibility.

[0005]

According to the present invention, one of the above objects is to provide a thermoplastic resin composition comprising a thermoplastic polyurethane and an aromatic vinyl compound-conjugated diene block copolymer. The weight ratio of aromatic vinyl compound-conjugated diene block copolymer is 6
0/40 or more, the thermoplastic polyurethane is 2-
A polyurethane having a hardness (JIS-A) of 90 or less obtained by reacting a polyester diol containing a methyl-1,3-propanediol component as a diol component and having a number average molecular weight of 1000 to 6000, an organic diisocyanate and a chain extender, And the aromatic vinyl compound-conjugated diene block copolymer has an aromatic vinyl compound component content of 5 to 50% by weight and a melt flow rate (200 ° C.,
5 kg) 30 or less aromatic vinyl compound-conjugated diene block copolymer. It is achieved by providing a thermoplastic resin composition. Further, according to the present invention, the above-mentioned other object is achieved by providing a film made of the above thermoplastic resin composition.

Thermoplastic polyurethane is generally obtained by reacting a polymer diol, an organic diisocyanate and a chain extender. In the present invention, the polymer diol is a 2-methyl-1,3-propanediol component, _{-O-CH 2 -CH (CH 3} ) a number average molecular weight containing -CH ₂ -O-] as diol component 1000
It is important to use 6000 polyester diols.

The polyester diol used in the present invention is
2-methyl-1, as at least part of the diol component,
It has a 3-propanediol component. When a polyester diol having no 2-methyl-1,3-propanediol component as the diol component is used, the resulting thermoplastic polyurethane is mixed with the above aromatic vinyl compound-conjugated diene block copolymer to prepare a resin composition. Even if formed, because the resulting resin composition has a large dispersed particle size of the aromatic vinyl compound-conjugated diene block copolymer,
Elastic recovery and strength are insufficient, and flexibility is also poor, which is not preferable. In general, the higher the proportion of the 2-methyl-1,3-propanediol component in the diol component, the better the elastic recovery, strength and flexibility of the resulting resin composition. It is preferable that mol% or more is 2-methyl-1,3-propanediol component, and 40 mol% or more is 2
More preferably, it is a methyl-1,3-propanediol component.

As described above, the diol component in the polyester diol in the present invention is 2-methyl-1,3-
It may be composed of a propanediol component and another diol component. Examples of the diol component that can be contained together with the 2-methyl-1,3-propanediol component include ethylene glycol, 1,3-propanediol,
1,2-propanediol, 1,4-butanediol,
Neopentyl glycol, 1,6-hexanediol,
Examples thereof include diol components derived from saturated aliphatic diols such as 2-methyl-1,8-octanediol and 1,9-nonanediol, and two or more kinds of these diol components may be contained. Among these, ethylene glycol and / or 1,4-butanediol are preferable because the effects derived from the 2-methyl-1,3-propanediol component are not easily lost. Furthermore, in the polyester diol in the present invention, a trifunctional or higher functional polyol component may coexist as long as the flexibility of the resulting thermoplastic resin composition is not deteriorated. The content of the trifunctional or higher functional polyol component is preferably 5 mol% or less based on the total diol components.

Examples of the dicarboxylic acid component which constitutes the polyester diol together with the diol component include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid,
Derived from a dicarboxylic acid such as 2-methylsuccinic acid, 2-methyladipic acid, 3-methyladipic acid, 3-methylpentanedioic acid, 2-methyloctanedioic acid or its ester-forming derivative (eg, esterified product) A dicarboxylic acid component is included.

The polyesterdiol used in the present invention has a number average molecular weight of 1,000 to 6,000. When the number average molecular weight is less than 1,000, the resulting polyurethane has insufficient low temperature flexibility and heat resistance, and thus the obtained resin composition has insufficient performance such as flexibility. On the other hand, when the number average molecular weight is more than 6000, the moldability becomes insufficient, such that the melt viscosity tends to increase during extrusion molding of the resulting thermoplastic resin composition, which is not preferable.

The method for producing the polyester diol used in the present invention is not particularly limited. Therefore, the polyester diol can be produced by a method similar to the known method used in the production of polyesters such as polyethylene terephthalate and polybutylene terephthalate, that is, transesterification or direct esterification followed by melt polycondensation reaction. . In the polycondensation reaction, a titanium-based or tin-based polycondensation catalyst may be used. However, when a titanium-based polycondensation catalyst is used, it is preferable to deactivate the polycondensation catalyst in the obtained polyester diol after the polycondensation reaction. By deactivating the polycondensation catalyst, it is possible to suppress the deterioration of the block property of the hard segment and the soft segment, which gradually occurs while the obtained thermoplastic polyurethane is molten and retained at a high temperature,
The heat resistance that the thermoplastic polyurethane originally had even in the film obtained from the resin composition by the melt extrusion molding method,
Various properties such as elastic recovery are effectively exhibited.

As a method for deactivating the polycondensation catalyst in the polyester diol, contact treatment with water is preferable. For example, 1 to 4% by weight of water is added to the polyester diol, and the mixture is stirred at 80 to 150 ° C. It is possible to employ a method of stirring at 100 to 150 ° C. while passing water vapor through the polyester diol. In addition, the polycondensation catalyst can be deactivated by adding a phosphorus compound which is generally used for deactivating the catalyst of polyester.

In the present invention, it is preferable to use the above polyester diol alone as the polymer diol, but if desired, other polymer diols (for example, polycarbonate diol, polyether diol, polyester other than the above polyester diol) may be used. Diol etc.) may be used together. The amount of the other polymer diol used is preferably 30% by weight or less based on the whole polymer diol.

The organic diisocyanate used in the present invention includes 4,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, tolylene diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4 '
Examples are the organic diisocyanates known to be commonly used in polyurethane production, such as dicyclohexylmethane diisocyanate. Among these,
4,4'-diphenylmethane diisocyanate is preferred.

Further, in the present invention, as the chain extender,
Chain extenders known to be commonly used in polyurethane production can be used. As the chain extender, a low molecular weight compound having a molecular weight of 300 or less and containing at least two hydrogen atoms capable of reacting with an isocyanate group (-NCO) in the molecule is preferable. As examples thereof, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis (2
Examples include diols such as -hydroxyethoxy) benzene, 1,4-cyclohexanediol, bis (β-hydroxyethyl) terephthalate and xylylene glycol. These chain extenders may be used alone or in admixture of two or more. Among these chain extenders, 1,
4-Butanediol is particularly preferred.

In the production of polyurethane, based on the total amount of active hydrogen atoms (that is, hydrogen atoms capable of reacting with isocyanate groups) of the polymer diol and the chain extender, isocyanate per mole of active hydrogen atoms is used. The number of moles of the group is 0.90 to 1.30, preferably
It is preferable to use the organic diisocyanate in a ratio such that it is 0.95 to 1.30.

As a method for producing a thermoplastic polyurethane by reacting a polymer diol, an organic diisocyanate and a chain extender, known urethanization reaction techniques such as melt polymerization and solution polymerization can be adopted. Among them, it is preferable to carry out melt polymerization in the substantial absence of a solvent, and particularly preferable is a continuous melt polymerization method using a multi-screw extruder. The melt polymerization temperature is not particularly limited,
It is preferably 180 ° C. or higher and 260 ° C. or lower.

In addition, a colorant,
Various additives such as flame retardants, UV absorbers, antioxidants, hydrolysis resistance improvers, antifungal agents; various fibers such as glass fibers and polyester fibers; inorganic substances such as mica and talc; various coupling agents, etc. You may select suitably and may add.

It is important that the thermoplastic polyurethane used in the present invention has a hardness (JIS-A) of 90 or less. When the hardness is 90 or more, the flexibility of the obtained thermoplastic resin composition becomes insufficient.

Aromatic vinyl compound used in the present invention
The conjugated diene block copolymer contains 5 to 50% by weight of an aromatic vinyl compound component and has a melt flow rate (200 ° C., 5 kg) of 30 or less. The block copolymer contains one or more, preferably two or more, polymer blocks mainly containing an aromatic vinyl compound component, and further contains one or more polymer blocks mainly containing a conjugated diene compound component. It is a thing. When the aromatic vinyl compound component content in the block copolymer exceeds 50% by weight, the resulting thermoplastic resin composition has a particle diameter of aromatic vinyl compound-conjugated diene block copolymer particles dispersed therein. It is not preferable because the elastic recovery property, the strength and the like are deteriorated probably because of the large value. On the other hand, when the content of the aromatic vinyl compound component is less than 5% by weight, disadvantages such as increase in tackiness of the film formed from the thermoplastic resin composition occur, which is not preferable.

When the melt flow rate (200 ° C., 5 kg) of the block copolymer exceeds 30, the dispersion state of the aromatic vinyl compound-conjugated diene block copolymer in the thermoplastic resin composition is poor. In addition, elastic recovery, strength and flexibility deteriorate, and film formation becomes difficult. Elastic recovery of the thermoplastic resin composition obtained, strength,
The melt flow rate of the aromatic vinyl compound-conjugated diene block copolymer is preferably 20 or less, and more preferably 10 or less from the viewpoint that flexibility and film-forming property are particularly improved. The lower limit of the melt flow rate is not particularly limited, but is preferably 0.1 or more.

Examples of the aromatic vinyl compound component constituting the block copolymer include components derived from an aromatic vinyl compound such as styrene, α-methylstyrene and vinyltoluene. Examples of the conjugated diene compound component include components derived from a conjugated diene compound such as isoprene, butadiene, and 1,3-pentadiene.

In the thermoplastic resin composition of the present invention,
The mixing ratio of the thermoplastic polyurethane having the specific structure to the specific aromatic vinyl compound-conjugated diene block copolymer is 60 by weight ratio of thermoplastic polyurethane / aromatic vinyl compound-conjugated diene block copolymer. /
It is important that it is 40 or more. When the weight of the thermoplastic polyurethane is less than 60% by weight based on the total weight of the thermoplastic polyurethane and the aromatic vinyl compound-conjugated diene block copolymer, the elastic recovery property is higher than that of the thermoplastic polyurethane alone. However, it is not preferable because properties such as strength and heat resistance are largely deteriorated. From the viewpoint that properties such as elastic recovery, strength, and heat resistance are particularly good, the weight ratio of the thermoplastic polyurethane / aromatic vinyl compound-conjugated diene block copolymer is preferably 70/30 or more.

From the viewpoint of the performance of the obtained resin composition, there is no particular upper limit on the weight ratio of the thermoplastic polyurethane / aromatic vinyl compound-conjugated diene block copolymer.
However, when the amount of the thermoplastic polyurethane is too large, the purpose of the present invention is not met from the economical point of view. Therefore, the weight ratio of the thermoplastic polyurethane / aromatic vinyl compound-conjugated diene block copolymer is kept within the range of 90/10 or less. Is desirable.

The thermoplastic resin composition of the present invention can be produced by a usual polymer blending method except that the thermoplastic polyurethane and the aromatic vinyl compound-conjugated diene block copolymer are used. For example, the above-mentioned thermoplastic polyurethane and aromatic vinyl compound-conjugated diene block copolymer were pre-mixed at a predetermined ratio using a vertical or horizontal mixer which is usually used for mixing resin materials. After that, it is produced by kneading under heating in a batch system or a continuous system using a single-screw or twin-screw extruder, a mixing roll, a Banbury mixer and the like. Upon mixing, light resistance, stabilizer for improving heat resistance, plasticizer, lubricant such as aliphatic amide, filler,
You may add additives, such as an antistatic agent and a pigment, in the quantity which does not impair the effect of this invention.

As a method for producing a film from the thermoplastic resin composition of the present invention, a conventional film forming method by melt extrusion molding such as inflation molding or T die molding can be adopted. As the conditions for melt extrusion molding, suitable conditions can be appropriately selected and adopted.

The above-mentioned specific thermoplastic polyurethane and aromatic vinyl compound constituting the thermoplastic resin composition of the present invention
With the conjugated diene block copolymer, minute particles of the aromatic vinyl compound-conjugated diene block copolymer can be uniformly dispersed in the matrix of the thermoplastic polyurethane simply by mixing them under melting conditions. Therefore, when a film is produced from the thermoplastic resin composition of the present invention, the film-forming stability is good and the film can be made thin.
Further, the obtained film is excellent in elastic recovery, heat resistance, strength and elongation and flexibility.

[0028]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, elastic recovery rate, strength, and flexibility (feel) were evaluated by the following methods.

[Elastic recovery rate] A test piece produced from a film having a film thickness of 50 μm formed by using a T-die was subjected to a pulling speed of 200 at a temperature of 23 ° C. and a humidity of 65% RH.
After 200% elongation at mm / min, the stress was removed for 2 minutes, the stress was removed, and the return after 10 minutes was measured. Based on the test result, the elastic recovery rate was calculated according to the following formula. Elastic recovery rate (%) = [L′−L) / L] × 100 (where L: initial length, L ′: length 10 minutes after stress removal)

[Strength] Film thickness 50 formed by using T-die
The tensile elongation of the test piece prepared from the film having a thickness of μm was measured by performing a tensile test under conditions of a tensile speed of 200 mm / min, a temperature of 23 ° C. and a humidity of 65% RH.

[Flexibility (Handle)] A film having a film thickness of 50 μm formed by using a T-die was evaluated for its handiness (handiness) according to the following criteria. ◯: It is soft without any mess. Δ: Slightly stiff and slightly soft feeling, but practically no problem as an elastic film. X: Rigid, lacking in softness, unsuitable as a stretch film.

In the examples, the compounds are represented by the abbreviations shown in Table 1 below.

[Table 1]

[Reference Example 1] (Production of Polyesterdiol A) 108 kg of MPrG and 146 kg of AD were charged into a reactor, and nitrogen gas was passed through the system under atmospheric pressure to obtain about 220
The esterification reaction was carried out at a temperature of ° C while distilling the produced water out of the system. When the acid value of the produced polyester was 30 or less, tetraisopropyl titanate was added, and the polycondensation reaction was continued while reducing the pressure to 200 to 100 mmHg. When the acid value reached 1.0, the degree of vacuum was gradually raised by a vacuum pump to complete the reaction. As a result, 20 polyester diols having a number average molecular weight of 4000 (this is referred to as “polyester diol A”) were obtained.
5 kg was obtained.

[Reference Example 2] (Production of polyester diol B) MPrG and AD were charged in a reactor, and an esterification reaction and a polycondensation reaction were carried out in the same manner as in Reference Example 1 to give a number average molecular weight of 2
000 polyester diols were obtained. The resulting polyester diol was heated to 100 ° C., 3% by weight of water was added, and the mixture was stirred at the same temperature for 2 hours to deactivate the titanium catalyst, and then the water was distilled off under reduced pressure. By this treatment, a polyester diol in which the titanium catalyst was deactivated (this is referred to as "polyester diol B") was obtained.

Reference Examples 3 to 5 (Production of Polyester Diols C, D and E) The diols used were mixed diols of MPrG and ED (Reference Example 3), mixed diols of MPrG, ED and BD (Reference Example 4). ) Or BD (Reference Example 5) except that the esterification reaction and polycondensation reaction were performed in the same manner as in Reference Example 1 to obtain a polyester diol having a number average molecular weight of 2000. The obtained polyester diol was inactivated in the same manner as in Reference Example 2 to deactivate the titanium catalyst. This treatment yielded polyester diols in which the titanium catalyst was deactivated (these are respectively referred to as "polyester diols C, D and E"). The compositions of these polyester diols are shown in Table 2.

[0036]

[Table 2]

Reference Example 6 {Production of Polyurethane P} The polyester diols A, MDI and BD obtained in Reference Example 1 were mixed at a molar ratio of polyester diol A / MDI / BD of 1/3/2. And, at a speed at which the total amount of these becomes 300 g / min, a twin-screw extruder (30 mm
φ; L / D = 36; cylinder temperature: each block was set in a range of about 200 ° C. to about 250 ° C.), and a continuous melt polymerization reaction was performed. The resulting thermoplastic polyurethane melt was continuously extruded in strands into water, then cut with a pelletizer and formed into pellets. The pellets were dehumidified and dried at 80 ° C. for 20 hours to obtain a thermoplastic polyurethane having a hardness (JIS-A) of 75 (this is referred to as “polyurethane P”).

[Reference Examples 7 to 10] {Polyurethane Q to
Production of T)} Instead of polyester diol A, polyester diol B obtained in reference example 2 (reference example 7), polyester diol C obtained in reference example 3 (reference example 8), reference example 4
Continuous melt polymerization reaction and pelletization were conducted in the same manner as in Reference Example 6 except that the polyester diol D obtained in (Reference Example 9) or the polyester diol E obtained in Reference Example 5 (Reference Example 10) was used. By dehumidifying and drying, thermoplastic polyurethanes (these are referred to as "polyurethane Q, R, S and T") were obtained. The hardness (JIS-A) of these thermoplastic polyurethanes is 75 (polyurethane Q), 78 (polyurethane R),
79 (Polyurethane S) and 82 (Polyurethane T)
Met.

Example 1 75% by weight of the thermoplastic polyurethane P obtained in Reference Example 6 was added with 21% by weight of styrene component (hereinafter abbreviated as “St content”) and melt flow rate (200 ° C., 5 kg). (Hereinafter abbreviated as "MFR") 3
A thermoplastic resin composition was manufactured by melt-kneading 25% by weight of SIS at dg / min with a 25 mmφ extruder (cylinder temperature and die temperature: 205 ° C.). The formed thermoplastic resin composition was extruded from a T die and wound through a cooling roll to obtain a film having a thickness of 50 μm. An attempt was made to reduce the film thickness to 20 μm, but stable film formation was possible even at 20 μm. The obtained thickness 5
After the 0 μm film was left at 25 ° C. for 7 days, elastic recovery, strength and flexibility were evaluated. The evaluation results are shown in Table 3.

[Examples 2 to 4] 75% by weight of the thermoplastic polyurethanes Q to S obtained in Reference Examples 7 to 9 were respectively added.
St content 21% by weight, MFR (200 ° C, 5 kg) 3
25% by weight of SIS was melt-kneaded in the same manner as in Example 1 to form a film, thereby obtaining a film of a thermoplastic resin composition having a thickness of 50 μm. After leaving each of the obtained films in the same manner as in Example 1, evaluation was performed and the results shown in Table 3 were obtained. The film-forming property was stable in all cases.

Example 5 75% by weight of the thermoplastic polyurethane Q obtained in Reference Example 7 had a St content of 28% by weight,
25% by weight of SBS of MFR6 was melt-kneaded in the same manner as in Example 1 to form a film, thereby obtaining a film made of a thermoplastic resin composition and having a thickness of 50 μm. After leaving the obtained film in the same manner as in Example 1, the film was evaluated and the results shown in Table 3 were obtained. The film forming property was stable.

Comparative Example 1 50 wt% of the thermoplastic polyurethane Q obtained in Reference Example 7 was added with St content of 21 wt%,
MFR (200 ° C, 5 kg) 3 SIS 50 wt%,
Melt-kneading and film formation were carried out in the same manner as in Example 1 to obtain a film of a thermoplastic resin composition having a thickness of 50 μm. After leaving the obtained film in the same manner as in Example 1, the film was evaluated and the results shown in Table 3 were obtained. The film forming property was unstable.

Comparative Example 2 75% by weight of the thermoplastic polyurethane Q obtained in Reference Example 7 was mixed with St content of 60% by weight,
SIS 25% by weight of MFR (200 ° C, 5 kg) 30
Was melt-kneaded in the same manner as in Example 1 to form a film, thereby obtaining a film of a thermoplastic resin composition having a thickness of 50 μm. The obtained film was allowed to stand in the same manner as in Example 1 and evaluated, and the results shown in Table 3 were obtained. The film forming property was unstable.

Comparative Example 3 75% by weight of the thermoplastic polyurethane T obtained in Reference Example 10 was added with 25% by weight of SIS having a St content of 21% by weight and MFR (200 ° C., 5 kg) 3.
Was melt-kneaded in the same manner as in Example 1 to form a film, thereby obtaining a film of a thermoplastic resin composition having a thickness of 50 μm. After leaving each of the obtained films in the same manner as in Example 1, evaluation was performed and the results shown in Table 3 were obtained. The film forming property was unstable.

[0045]

[Table 3]

From Table 3 above, Example 1 according to the present invention
The thermoplastic resin composition of ~ 5 gives a film excellent in elastic recovery, strength and flexibility (texture).
In Examples 2 to 5 in which the thermoplastic polyurethane produced by using the polyester diol in which the polycondensation catalyst has been deactivated is used, the elastic recovery properties, heat resistance, and elongation of the film are further improved. I understand. On the contrary,
From the thermoplastic resin compositions of Comparative Examples 1 to 3 which are different from the present invention, only films having inferior elastic recovery, strength and flexibility (texture) were obtained, and the film-forming property was found to be unstable. .

[0047]

According to the present invention, there is provided a thermoplastic resin composition having excellent elastic recovery, strength and flexibility possessed by thermoplastic polyurethane. The thermoplastic resin composition, since the aromatic vinyl compound-conjugated diene block copolymer is blended in the thermoplastic polyurethane,
It is cheaper than thermoplastic polyurethane alone. The film of the present invention effectively exhibits the characteristics of the thermoplastic resin composition and is useful as a stretchable film.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-48-14792 (JP, A) JP-A-6-128521 (JP, A) JP-B-48-27903 (JP, B1) (58) Field (Int.Cl. ⁷ , DB name) C08L 75/04-75/12 C08J 5/18

Claims (2)

(57) [Claims] 1. A thermoplastic resin composition comprising a thermoplastic polyurethane and an aromatic vinyl compound-conjugated diene block copolymer, wherein a weight ratio of thermoplastic polyurethane / aromatic vinyl compound-conjugated diene block copolymer is 60 /. 40 or more, the thermoplastic polyurethane is 2
A polyurethane having a hardness (JIS-A) of 90 or less obtained by reacting a polyester diol containing a methyl-1,3-propanediol component as a diol component and having a number average molecular weight of 1000 to 6000, an organic diisocyanate and a chain extender. And the aromatic vinyl compound-conjugated diene block copolymer has an aromatic vinyl compound component content of 5 to 50% by weight and a melt flow rate (200
C., 5 kg) 30 or less aromatic vinyl compound-conjugated diene block copolymer, a thermoplastic resin composition characterized in that. 2. A film comprising the thermoplastic resin composition according to claim 1.