JPH075818B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention comprises a modified product of polyphenylene ether, a polyamide and a block copolymer elastic body, and has impact resistance represented by Izod impact strength and flexural modulus. The present invention relates to a thermoplastic resin composition having excellent rigidity, heat resistance typified by heat distortion temperature, and moldability which are excellent.

<Prior Art> Polyphenylene ether is a resin that excels in various properties such as heat resistance and rigidity, and is attracting attention as engineering plastics, but it has poor impact resistance.
Further, since the melt viscosity is high, a high temperature is required to mold the resin itself under melting, which causes various undesirable problems such as discoloration and oxidative deterioration.

In order to solve such a problem, when a composition of polyphenylene ether and polyamide or a composition of polyphenylene ether, polyamide and rubber-like substance is melt-kneaded, (a) carbon-carbon double bond or carbon-
A carbon triple bond and (b) a carboxylic acid group, an acid anhydride group,
It is possible to modify the composition by melt-kneading together a compound having an acid amide group, an imide group, a carboxylic acid ester group, an epoxy group, an amino group or a hydroxyl group at the same time.
No. 966 and Japanese Patent Laid-Open No. 56-49753.

In addition, 1, which has a carboxyl group or an acid anhydride group,
A composition of a polyphenylene ether modified with a 2-substituted olefin compound and a polyamide is disclosed in JP-A-59-66452.

<Problems to be Solved by the Invention> However, the modified polymer produced by the method described in JP-B No. 60-11966 has the above-mentioned (a) at the same time when melt-kneading the polyphenylene ether and the polyamide.
Since it is produced by a method of adding a specific compound having (b), polyphenylene ether and polyamide are randomly cross-linked through the compound having a specific structure, so that there is a problem in moldability and impact resistance is also poor. It was enough.

Further, a resin obtained by melt-kneading polyphenylene ether and polyamide described in JP-A-56-49753, and further adding a specific compound having the above (a) and (b) to a composition composed of a rubber-like substance. The composition was improved in molding processability and impact resistance as compared with the above-mentioned Japanese Patent Publication, but was still unsatisfactory in impact resistance.

Even a resin composition comprising a modified polyphenylene ether and a polyamide previously modified with a specific compound described in JP-A No. 59-66452 has insufficient impact resistance and heat resistance, and is still unsatisfactory.

Therefore, an object of the present invention is to develop a resin having extremely excellent impact resistance, high level of rigidity, heat resistance, and excellent moldability.

<Means for Solving Problems> As a result of intensive investigations by the present inventors to achieve the above object,
By compounding a specific block copolymer elastic as a polyphenylene ether preliminarily modified with a compound having a specific structure, a polyamide and a rubber-like substance,
The present invention has been completed by finding that a resin composition having extremely excellent impact resistance and other high level mechanical properties can be obtained.

That is, the present invention provides (A) general formula (Wherein Q ₁ , Q ₂ , Q ₃ and Q ₄ are each independently selected from the group consisting of hydrogen, halogen, hydrocarbon, halohydrocarbon, hydrocarbonoxy and halohydrocarbonoxy, and n
Represents the total number of monomer units and is an integer of 20 or more)
To 100 parts by weight of the polyphenylene ether of (a) carbon-carbon double bond or carbon-carbon triple bond and (b)
Modified products of polyphenylene ether obtained by reacting compounds having an acid amide group, an imide group, a carboxylic acid ester group, an epoxy group, an amino group or a hydroxyl group at the same time 5 to 90
% By weight, 5 to 90% by weight of (B) polyamide and (C) A
-BA 'type block copolymer elastic body (where A and A'are polymerized vinyl aromatic hydrocarbon blocks, and B
Is a polymerized conjugated diene block) and / or in the block copolymer elastic body, the intermediate polymer block part B is hydrogenated.
The present invention provides a thermoplastic resin composition prepared by mixing 5 to 60% by weight of an A'type block copolymer elastic body.

The thermoplastic resin composition of the present invention comprises (A) a modified polyphenylene ether, (B) a polyamide and (C) A-.
It is obtained by mixing a B-A 'type block copolymer elastic body and / or a hydrogenated A-B-A' type block copolymer elastic body.

The polyphenylene ether used for preparing the component (A) constituting the resin composition of the present invention is preferably a homopolymer or copolymer containing one or more units represented by the above general formula.

Although the production method of polyphenylene ether is not particularly limited, for example, U.S. Patent Nos. 3,306,874 and 3,3,3
It can be prepared by reaction of phenols according to procedures such as those described in 06,875 and U.S. Pat. Nos. 3,257,357 and 3,257,358. These phenols include 2,6-dimethylphenol, 2,6
-Diethylphenol, 2,6-dibutylphenol, 2,6
-Dilaurylphenol, 2,6-dipropylphenol, 2,6-diphenylphenol, 2-methyl-6-ethylphenol, 2-methyl-6-cyclohexylphenol, 2-methyl-6-tolylphenol, 2-methyl -6-methoxyphenol, 2-methyl-6-butylphenol, 2,6-dimethoxyphenol, 2,3,6-trimethylphenol, 2,3,5,6-tetramethylphenol and 2,6-diethoxyphenol Included, but not limited to.

Each of these may be reacted alone to give the corresponding homopolymer or with another phenol to give the corresponding copolymer having different units included in the above formula. In particular, 2,6-dimethylphenol and its corresponding polymer or poly (2,6-dimethyl-1,4-phenylene) ether, as well as 2,6-dimethylphenol and other phenols such as 2,3, Combined use with 6-trimethylphenol, 2-methyl-6-butylphenol and the like and copolymers corresponding thereto, such as poly (2,6-dimethyl-co-2-methyl-6-butyl-1,4-phenylene) ether Is mentioned.

Further, (a) a carbon-carbon double bond or a carbon-carbon triple bond used in the preparation of the component (A) and (b) an acid amide group, an imide group, a carboxylic acid ester group, an epoxy group, an amino group or a hydroxyl group are simultaneously formed. Specific examples of the compound having maleimide, maleic hydrazide, a reaction product of maleic anhydride and a diamine, for example, (Wherein R represents an aliphatic or aromatic group), epoxidized natural fats and oils such as epoxidized soybean oil, acrylic acid, butenoic acid, crotonic acid, vinyl acetic acid, methacrylic acid , Pentenoic acid, angelic acid,
Cypric acid, 2-pentenoic acid, 3-pentenoic acid, α-ethylacrylic acid, β-methylcrotonic acid, 4-pentenoic acid, 2-hexenoic acid, 2-methyl-2-pentenoic acid, 3
-Methyl-2-pentenoic acid, α-ethyl crotonic acid, 2,
2-dimethyl-3-butenoic acid, 2-heptenoic acid, 2-octenoic acid, 4-decenoic acid, 9-undecenoic acid, 10-undecenoic acid, 4-dodecenoic acid, 5-dodecenoic acid, 4-tetradecenoic acid, 9 -Tetradecenoic acid, 9-hexadecenoic acid, 2-octadecenoic acid, 9-octadecenoic acid, eicosenoic acid, docosenoic acid, erucic acid, tetracosenoic acid, mycolic acid, 2,4-pentadienoic acid, 2,4-hexadienoic acid, diallylacetic acid , Geranium acid, 2,4-decadienoic acid, 2,4-dodecadienoic acid, 9,12-hexadecadienoic acid, 9,12-octadecadienoic acid, hexadecatrienoic acid, linoleic acid, linolenic acid, octadecatriene acid,
Eicosadienoic acid, eicosatrienoic acid, eicosatetraenoic acid, ricinoleic acid, eleostearic acid, oleic acid, eicosapentaenoic acid, erucic acid, docosadienoic acid, docosatrienoic acid, docosatetraenoic acid, docosapentaenoic acid, tetracosenoic acid , Esters of unsaturated carboxylic acids such as hexacocenoic acid, hexacodienoic acid, octacocenoic acid and traacontenoic acid, acid amides, anhydrides, or allyl alcohol, crotyl alcohol, methyl vinyl carbinol, allyl carpinol, methyl propenyl carpinol, 4 -Penten-1-ol, 10-
Undecen-1-ol, propargyl alcohol, 1,
4-pentadiene-3-ol, 1,4-hexadiene-3
- ol, 3,5-hexadiene-2-ol, 2,4-hexadiene-1-ol, formula _{CnH 2 n -5 OH, CnH 2} n -7 OH, Cn
Alcohols represented by H ₂ n _-9 OH (where n is a positive integer), 3-butene-1,2-diol, 2,5-dimethyl-3-
Hexene-2,5-diol, 1,5-hexadiene-3,4-
Diol, 2,6-unsaturated alcohol such as octadiene-4,5-diol, or the OH group of such unsaturated alcohols,換Tsuta unsaturated amines placed -NH ₂ group or butadiene, low, such as isoprene, Polymers (for example, those having an average molecular weight of about 500 to 10,000) or high molecular weight substances (for example, those having an average molecular weight of 10,000 or more) to which maleic anhydride, phenols are added, or amino groups, carboxylic acid groups, hydroxyl groups, The thing which introduced the epoxy group etc. is mentioned. The definition of a compound having a specific structure in the present invention also includes a compound containing two or more functional groups of group (a) and two or more (same or different) functional groups of group (b). Needless to say, it is also possible to use two or more specific compounds.

The amount of the specific compound used in the present invention is 0.1 to 20 parts by weight, preferably 0.3 to 100 parts by weight of polyphenylene ether.
The range is up to 10 parts by weight. If the amount is less than 0.1 part by weight, a balanced improvement in impact strength, flexural strength and heat resistance is not observed in the resin composition comprising the modified product, polyamide and block copolymer elastic material.

The following method can be adopted for the preparation of the component (A).

[A] A method in which a compound having a specific structure is added to a solution containing polyphenylene ether, and the mixture is stirred at a temperature of 60 ° C to 150 ° C for several tens of minutes to several hours [b] 220 ° C to 370 in a substantially solvent-free system A method in which each component is melt-kneaded in the temperature range of 20 ° C to 30 minutes, preferably 30 seconds to 5 minutes.

The method [a] is preferably used when there is an existing reaction apparatus or purification apparatus, but the method [b] can be modified by light equipment such as a general-purpose twin-screw extruder. There is an advantage in that it can be changed in a short time without the solvent removal step and the polymer purification step.

A radical generator may be used as a catalyst for the preparation of the component (A), and examples of the radical generator include known organic peroxides and diazo compounds. Preferred specific examples include benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide and azobisisobutyronitrile. To be The amount of the radical generator used is 3 to 30 parts, preferably 5 to 100 parts of the compound having the specific structure.
It ranges from ~ 20 copies. When it is less than 3 parts, the effect of the radical generator as a catalyst is not sufficiently exhibited.

The polyamide (B) used in the present invention is a polyamide obtained by ring-opening polymerization of lactams such as ε-caprolactam and ω-dodecalactam, 6-aminocaproic acid,
Polyamides derived from amino acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid, ethylenediamine,
Tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,
2,4- / 2,4,4-trimethylhexamethylenediamine, 1,3
-And 1,4-bis (aminomethyl) cyclohexane,
Aliphatic, alicyclic and aromatic diamines such as bis (4,4′-aminocyclohexyl) methane, meta and paraxylylenediamine and adipic acid, suberic acid, sebacic acid,
Dodecanedioic acid, 1,3- and 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, polyamides derived from aliphatic, alicyclic, aromatic dicarboxylic acids such as dimer acid and copolyamides thereof, It is a mixed polyamide. Of these, polycaproamide (nylon 6) and polyundecane amide (nylon 1) are usually used.
1), polydodecanamide (Ninero 12), polyhexamethylene adipamide (nylon 66) and copolyamides containing these as the main components are useful. As a method for polymerizing the polyamide, generally known melt polymerization, solid phase polymerization and a combination of these methods can be adopted. The polymerization degree of polyamide is not particularly limited, and the relative viscosity (polymer 1 g is 98%
A polyamide dissolved in 100 ml of concentrated sulfuric acid and measured at 25 ° C) within the range of 2.0 to 5.0 can be arbitrarily selected according to the purpose.

The block copolymer elastic material used as the component (C) in the present invention is an AB-A 'type block copolymer elastic material composed of a vinyl aromatic hydrocarbon and a conjugated diene. ′ 'S may be the same or different and are thermoplastic homopolymers or copolymers derived from aromatic moieties or vinyl aromatic hydrocarbons which may be monocyclic or polycyclic. Examples of such vinyl aromatic hydrocarbons include styrene, α-methylstyrene, vinyltoluene, vinylxylene, ethylvinylxylene, vinylnaphthalene, and mixtures thereof. The intermediate polymer block B is composed of a conjugated diene hydrocarbon, for example, 1,3-
Butadiene, 2,3-dimethylbutadiene, isoprene,
Examples include polymers derived from 1,3-pentadiene and mixtures thereof. In addition, hydrogenation AB
The A′-type block copolymer elastic body is the above-mentioned ABA ′.
The mold block copolymer elastic body is one in which the intermediate polymer block portion is hydrogenated, and may be hydrogenated in any proportion.

The block copolymerized elastic body can be produced by a generally known method. For example, it can be produced by the method shown in US Pat. No. 3,251,905, US Pat. No. 3,231,635 and the like. A hydrogenated block copolymer elastic body can be produced by hydrogenating the block copolymer elastic body according to the method described in US Pat. No. 3,431,323.

In the thermoplastic resin composition of the present invention, the compounding ratio of the modified polyphenylene ether (A), the polyamide (B) and the block copolymer elastic body (C) is such that (A) is 5 to 90% by weight, preferably 15%. ~ 80% by weight, particularly preferably 20-70
% By weight, 5 to 90% by weight of (B), preferably 10 to 80% by weight, particularly preferably 15 to 70% by weight and 5 to 60% of (C).
% By weight, preferably 8 to 50% by weight, particularly preferably 10 to
40% by weight. If (A) is less than 5% by weight, heat resistance and rigidity are poor, and if (A) is more than 90% by weight, impact resistance is poor and molding processability is deteriorated, which is not preferable. (B) is 5
If it is less than 10% by weight, moldability is poor, and if it exceeds 90% by weight, rigidity and heat resistance are poor, which is not preferable.
When (C) is less than 5% by weight, impact resistance is poor, and (C)
Is more than 60% by weight, the rigidity and heat resistance are poor and the molding processability is also deteriorated, which is not preferable.

The method for producing the thermoplastic resin composition of the present invention is not particularly limited, and a generally known method can be adopted.
That is, the modified polyphenylene ether (A), the polyamide (B), and the block copolymer elastic body (C) are uniformly mixed in a pellet, powder, or strip state using a high-speed stirrer, and then sufficiently kneaded. Various methods such as a method of melt-kneading with a uniaxial or multi-screw extruder having an ability or a method of melt-kneading with a Banbury mixer or a rubber roll machine can be adopted. Further, a modified polyphenylene ether (A) and a polyamide (B), a polyamide (B) and a block copolymer elastic body (C), and a modified polyphenylene ether (A) and a block copolymer elastic body (C)
It is also possible to preliminarily knead the above ingredients and to knead them by adjusting them to a predetermined mixing ratio.

The thermoplastic resin composition of the present invention comprises a modified polyphenylene ether (A), a polyamide (B), a block copolymer elastic body (C), and optionally a polystyrene (P).
S), styrene / acrylonitrile copolymer (SAN), polymethylmethacrylate (PMMA) styrene / methyl methacrylate / acrylonitrile copolymer, α-methylstyrene / acrylonitrile copolymer, α-methylstyrene /
Styrene / acrylonitrile copolymer, α-methylstyrene / methyl methacrylate / acrylonitrile copolymer, p-methylstyrene / acrylonitrile copolymer,
Styrene / N-phenylmaleimide copolymer, styrene /
Vinyl-based polymers such as maleic anhydride copolymers, acrylonitrile-butadiene-styrene terpolymers (AB
S) resin, methacrylic acid resin-butadiene-styrene terpolymer (MBS) resin, AES resin, AAS resin, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, or other thermoplastic resin is appropriately mixed, polyethylene, polypropylene, ethylene / Propylene copolymer, ethylene / butene-1 copolymer, ethylene / propylene / dicyclopentadiene copolymer, ethylene /
Propylene / 5-ethylidene 2-norbornene copolymer,
Further control of desirable physical properties and characteristics by appropriately mixing polyolefin rubber such as ethylene / propylene / 1,4-hexadiene copolymer, ethylene / vinyl acetate copolymer and ethylene / butyl acrylate copolymer It is also possible to do so. Depending on the purpose, pigments and dyes,
Add reinforcing materials and fillers such as glass fiber, metal fiber, metal flake, carbon fiber, heat stabilizer, antioxidant, UV absorber, light stabilizer, lubricant, plasticizer, antistatic agent and flame retardant. be able to.

<Example> Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. Izod impact strength is ASTM D256-56, Me
thod A, heat distortion temperature ASTM D648-56, flexural modulus
It was measured according to ASTM D790-61. Izod impact strength and flexural modulus were measured in an absolutely dry state.

Reference Example 1 (Production of Modified Product (A) of Polyphenylene Ether) A-1: Powder of polyphenylene ether was charged into an extruder by adding 7 parts by weight of N-phenylmaleimide to 100 parts by weight of the polyphenylene ether, and extruded. Extrusion temperature is 320 ℃ while degassing the generated gas from the exhaust port attached to the machine.
Extrusion is carried out with a modified product of polyphenylene ether (A
-1) was produced.

10 g of this pellet was collected, pulverized into a fine powder and then 100
The mixture was heated and refluxed for 48 hours with a Soxhlet extractor using ml of methanol.

Then, it was dried under reduced pressure at 100 ° C. for 8 hours to obtain a sample. The presence of a carbonyl structure derived from the reaction of this sample with N-phenylmaleimide was confirmed by analysis of the absorption peak at 1600 to 1800 cm ^{-1 in} the Fourier integrated infrared absorption spectrum.

A-2: Polyphenylene ether powder was prepared by adding 5 parts by weight of methacrylic acid glycidyl ester and 0.5 part by weight of 2,5-dimethyl-2, to 100 parts by weight of the polyphenylene ether.
It was charged into an extruder together with 5-di (t-butylperoxy) hexyne-3, and a modified product of polyphenylene ether (A-2) was produced in the same manner as in A-1. After taking 10 g of this pellet and performing the same purification as in A-1 with a Soxhlet extractor, the presence of a carbonyl structure derived from the reaction with glycidyl methacrylate was determined by infrared absorption spectrum in the same manner as in A-1. It was confirmed.

A-3: Polyphenylene ether powder was added to 5 parts by weight of acrylamide and 0.5 parts by weight of the polyphenylene ether.
It was charged into an extruder together with 2 parts by weight of 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, and a modified product of polyphenylene ether (A-
3) was produced. After 10 g of this pellet was collected and purified by a Soxhlet extractor in the same manner as in A-1, the presence of a carbonyl structure derived from the reaction with acrylamide was confirmed by an infrared absorption spectrum in the same manner as in A-1.

Reference Example 2 (Production of Polyamide (B)) The following nylon 6, nylon 66, and nylon 12 were produced by the melt polymerization method.

Nylon 6: ε-caprolactam to concentrated sulfuric acid relative viscosity 2.75
Of nylon 6 (B-1) was polymerized.

Nylon 66: Nylon 66 (B-2) having a relative viscosity of concentrated sulfuric acid of 2.60 was polymerized from a molar salt of hexamethylenediamine and adibic acid.

Nylon 12: 12-aminododecanoic acid to concentrated sulfuric acid relative viscosity
2.35 nylon 12 (B-3) was polymerized.

Examples 1 to 14 Modified products of polyphenylene ether prepared in Reference Example (A
-1 to 3), polyamide (B-1 to 3) and block copolymer elastic material are unsaturated polystyrene-polybutadiene-polystyrene block copolymer "Cariflex" (Cariflex) manufactured by Gel Chemical Company.
1101 (C-1) and / or hydrogenated polystyrene-polybutadiene-polystyrene block copolymer "Kraton" G1 manufactured by Shell Chemical Company
652 (C-2) was mixed at the compounding ratio shown in Table 1, and 30 mmφ
The mixture was melt-kneaded using a twin-screw extruder and pelletized. The extrusion temperature was 280 ° C. Next, the pellets were vacuum dried, and then a test piece for measuring physical properties was molded by injection molding. During injection molding, the cylinder temperature was set to 280 ° C. The mold temperature was set to 80 ° C. The measurement results are shown in Table 1.

Comparative Examples 1 to 9 Modified products of polyphenylene ether (A), polyamide (B) and block copolymer elastic body (C) produced in Reference Examples, polyphenylene ether used as a raw material polymer in Reference Example 1 (hereinafter abbreviated as PPO). Was mixed at the compounding ratio shown in Table 2 and the physical properties were measured by the same methods as in the examples. The measurement results are shown in Table 2.

Comparative Examples 10 to 12 The PPO, the polyamide, the block copolymer elastic body and the specific compound used in the reference examples were mixed all together at the compounding ratio shown in Table 2, and the physical properties were measured by the same methods as in the examples. The measurement results are shown in Table 2.

Comparative Examples 13 to 15 The composition obtained by melt-kneading the PPO and the polyamide used in Reference Example 1 together with the specific compound was further mixed with the block copolymer elastic material at the compounding ratio shown in Table 2, and the physical properties were measured by the same methods as in the Examples. did. The measurement results are shown in Table 2.

The following is clear from the results of the examples and comparative examples.

The resin compositions of the present invention (Examples 1 to 14) were all high in Izod impact strength, heat deformation temperature and flexural modulus, and excellent in moldability.

On the other hand, the resin compositions (Comparative Examples 1 and 2) which did not contain polyamide and consisted only of the modified polyphenylene ether (A) and the block copolymer elastic body (C) had poor moldability.

The resin compositions (Comparative Examples 3 and 4) which did not contain a modified product of polyphenylene ether and consisted only of the polyamide (B) and the block copolymer elastic body (C) had a low heat distortion temperature.

The resin compositions (Comparative Examples 5 and 6) containing only the modified polyphenylene ether (A) and the polyamide (B) without the block copolymer elastic body had low Izod impact strength.

The resin compositions (Comparative Examples 7 and 8) containing the block copolymer elastic body (C) in an amount of more than 60% by weight have drawbacks such as low heat deformation temperature and bending elastic modulus, and poor moldability. Was there.

When the polyphenylene ether which was not modified with the compound having a specific structure was used (Comparative Example 9), the Izod impact strength was low. When a compound having a specific structure is melt-kneaded together with each component (Comparative Example 10
〜12), Izod impact strength and heat distortion temperature were not improved in balance.

Resin compositions (Comparative Examples 13 and 14) in which polyphenylene ether and polyamide were melt-kneaded with a compound having a specific structure and then mixed with a block copolymer elastic body were not improved as much as expected Izod impact strength. The workability was poor.

The resin composition (Comparative Example 15) obtained by melt-kneading the polyphenylene ether and the block copolymer elastic material together with the compound having a specific structure and then mixing the polyamide did not sufficiently improve the heat resistance.

<Effects of the Invention> As described above, the resin composition of the present invention has both impact resistance represented by Izod impact strength, rigidity represented by flexural modulus, and heat resistance represented by heat deformation temperature. It is excellent and has good moldability.

Claims (1)

[Claims] 1. (A) General formula (Wherein Q ₁ , Q ₂ , Q ₃ and Q ₄ are each independently selected from the group consisting of hydrogen, halogen, hydrocarbon, halohydrocarbon, hydrocarbonoxy and halohydrocarbonoxy, and n
Represents the total number of monomer units and is an integer of 20 or more. ) In the molecule of 0.1 to 20 parts by weight based on 100 parts by weight of the polyphenylene ether, (a) a carbon-carbon double bond or a carbon-carbon triple bond and (b) an acid amide group, an imide 5 to 90% by weight of a modified product of polyphenylene ether obtained by reacting a compound having a group, a carboxylic acid ester group, an epoxy group, an amino group or a hydroxyl group at the same time, (B) a polyamide 5 to 90% by weight
And (C) A-B-A 'type block copolymer elastomer (wherein A and A'are polymerized vinyl aromatic hydrocarbon blocks and B is a polymerized conjugated diene block) and / Alternatively, a thermoplastic resin composition comprising 5 to 60% by weight of a hydrogenated ABAA 'type block copolymer elastic body in which the intermediate polymer block portion B is hydrogenated in the block copolymer elastic body.