JP2009204097A - Heat shrinkable tube molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat shrinkable tube molded product formed of a thermoplastic elastomer resin composition which is sufficiently strong, rigid and flexible as required for a heat shrinkable tube in use for electrically insulating an automobile harness or an electric wire, a cable connection portion and a capacitor, superior in heat resistance and heat aging resistance, and suitable for extrusion molding. <P>SOLUTION: The heat shrinkable tube is formed of the heat-resistant thermoplastic elastomer resin composition in which a 0.01-10 pts.wt heat resistant agent (C) is incorporated with respect to a 100 pts.wt thermoplastic elastomer composed of a mixture of a 65-5 wt.% polyester block copolymer (A) and a 35-95 wt.% dynamically cross-linked thermoplastic elastomer composition (B). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention has sufficient strength, rigidity and flexibility that can be suitably used in parts requiring high heat resistance and heat aging resistance such as in an engine room of an automobile, and is excellent in heat resistance and heat aging resistance, and extrusion molding. The present invention relates to a heat-shrinkable tube molded body made of a thermoplastic elastomer resin composition suitable for the above.

  A polyester block copolymer having a crystalline aromatic polyester unit as a hard segment and an aliphatic polyether unit such as poly (alkylene oxide) glycol and / or an aliphatic polyester unit such as polylactone as a soft segment has a strength, Excellent mechanical properties such as impact resistance, elastic recovery, flexibility, low temperature and high temperature characteristics, and is thermoplastic and easy to mold, so automotive harnesses, wire / cable connections, capacitors, etc. It is widely used as a heat shrinkable tube for electrical insulation applications.

  Generally, the flexibility of the polyester block copolymer becomes more flexible as the soft segment ratio increases, while the heat resistance has a property of becoming better as the hard segment ratio is higher. Due to this property, high-hardness polyester block copolymers are used in applications that require heat resistance, and low-hardness polyester block copolymers that sacrifice heat resistance are used in applications that require flexibility. .

  However, in recent years, heat generation in the engine compartment has increased along with higher performance of automobiles, heat resistance requirements for electrical components have increased more than ever, and automotive parts are also heat resistant due to consideration for environmental issues. Since there is a demand for providing a thermoplastic elastomer having both properties and flexibility, there is a demand for further improvement in heat resistance even in heat-shrinkable tubes.

  However, in reality, thermoplastic elastomers that have sufficient heat resistance have not yet been obtained for heat-shrinkable tube applications that require flexibility and heat resistance, and heat-shrinkable tubes made of crosslinked polyethylene or fluoropolymers are used. In reality, the flexible polyester block copolymer has been applied only to parts having low heat resistance requirements.

  Under such circumstances, in recent years, various developments of heat-shrinkable tubes having both heat resistance and flexibility using polyester block copolymers have been reported.

  For example, a heat-shrinkable tube made of an aromatic polyester resin and a polyester elastomer (see, for example, Patent Document 1), a heat-shrinkable tube made of an aromatic polyester resin, a polyester elastomer, and large-sized inert external particles (for example, a patent) Reference 2), heat shrinkable tube made of polyethylene terephthalate, aromatic polycarbonate, polyester elastomer and large particle size (for example, Patent Document 3), and heat shrink made of polyethylene terephthalate, polyethylene naphthalate and polyester elastomer. A tube (for example, Patent Document 4) has been proposed. With such a configuration, although heat resistance can be improved, flexibility and heat resistance cannot be satisfied at a high level.

Further, a heat-shrinkable tube formed by a resin composition comprising a polyester block copolymer and an ethylene-methyl acrylate binary copolymer and then crosslinked by electron beam irradiation (see, for example, Patent Document 5) ), And a heat-shrinkable tube formed by forming a tube molded body with a polyester block copolymer composition containing an aliphatic dicarboxylic acid having a carbon-carbon unsaturated bond in the molecule as a monomer, followed by crosslinking by electron beam irradiation or the like ( For example, Patent Document 6) has been proposed, but in such a configuration, even if both heat resistance and flexibility can be achieved, the crosslinking step is essential after tube forming separately from the tube forming step, and the environmental load is reduced. There was a problem that the economy was inferior in terms of difficulty in reducing recycling.
Japanese Patent Laid-Open No. 10-25351 (pages 1 and 2) JP 10-46014 A (pages 1 and 2) JP-A-2004-52963 (first and second pages) JP 2002-264213 (pages 1 and 2) Japanese Patent Laid-Open No. 6-144843 (pages 1 to 3) JP 2000-95846 (Pages 1 and 2)

  The present invention has been achieved as a result of studies to solve the above-mentioned problems of the prior art, has necessary and sufficient strength, rigidity and flexibility, and has excellent heat resistance and heat aging resistance, and is suitable for extrusion molding. An object of the present invention is to provide a heat-shrinkable tube molded body made of a suitable thermoplastic elastomer resin composition.

  In order to achieve the above object, according to the present invention, a high-melting-point crystalline polymer segment (a1) mainly composed of crystalline aromatic polyester units, and a low melting point composed mainly of aliphatic polyether units and / or aliphatic polyester units. 65 to 5% by weight of a polyester block copolymer (A) mainly comprising a melting point polymer segment (a2), 10 to 50% by weight of a polyalkylene phthalate polyester polymer and / or copolymer (b1), and Mixture of 50 to 90% by weight of at least one (co) polymer (b2) selected from crosslinkable poly (meth) acrylate, (meth) acrylate copolymer, polyethylene / (meth) acrylate copolymer Is dynamically cross-linked thermoplastic elastomer when melt mixed in an extruder in the presence of a radical generator A heat-resistant thermoplastic elastomer resin composition comprising 0.01 to 10 parts by weight of a heat-resistant agent (C) with respect to 100 parts by weight of a thermoplastic elastomer composition obtained by mixing 35 to 95% by weight of the mer (B) A heat-shrinkable tube molded body characterized by comprising:

In the heat shrinkable tube of the present invention,
In addition to the components (A), (B), and (C), further comprising 0 to 25 parts by weight of the polycarbonate resin (D) and / or 0 to 25 parts by weight of the polyphenylene ether resin (E),
The weight ratio of the high-melting crystalline polymer segment (a1) and the low-melting polymer segment (a2) of the polyester block copolymer is 30/70 to 95/5,
The polyalkylene phthalate polyester polymer and / or copolymer (b1) is selected from polyalkylene terephthalate, polyalkylene terephthalate copolymer, polyalkylene isophthalate polyether ester and polyalkylene terephthalate copolymer polyether ester. At least one selected,
At least one (co) polymer (b2) selected from the dynamically cross-linked poly (meth) acrylate, (meth) acrylate copolymer, and polyethylene / (meth) acrylate copolymer is a polyacrylate elastomer. And / or being a polyethylene acrylate elastomer,
The heat-resistant agent (C) is one or more selected from the group consisting of an aromatic amine-based antioxidant, a hindered phenol-based antioxidant, a sulfur-based antioxidant and a phosphorus-based antioxidant, and / or Alternatively, it is preferable to use a polyamide resin and to be produced by extrusion molding the above heat-resistant thermoplastic elastomer resin composition, and by applying these conditions, it is more excellent. You can expect to get the effect.

  According to the present invention, as will be described below, a heat-shrinkable tube made of a thermoplastic elastomer resin composition that has necessary and sufficient strength, rigidity, and flexibility, is excellent in heat resistance and heat aging resistance, and is suitable for extrusion molding. A molded body can be obtained.

  Hereinafter, the present invention will be described in detail.

  The high-melting crystalline polymer segment (a1) of the polyester block copolymer (A) used in the present invention is mainly formed from an aromatic dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof. Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, anthracene dicarboxylic acid, diphenyl-4, Examples include 4'-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, and sodium 3-sulfoisophthalate. Although aromatic dicarboxylic acid is mainly used, if necessary, a part of the aromatic dicarboxylic acid may be converted to alicyclic dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, 4,4′-dicyclohexyldicarboxylic acid, etc. Alternatively, it may be substituted with an aliphatic dicarboxylic acid such as adipic acid, succinic acid, oxalic acid, sebacic acid, dodecanedioic acid, and dimer acid. Of course, ester-forming derivatives of dicarboxylic acids such as lower alkyl esters, aryl esters, carbonates, and acid halides can be used equally.

  Specific examples of the diol include diols having a molecular weight of 400 or less, for example, aliphatic diols such as 1,4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol, , 1-cyclohexanedimethanol, 1,4-dicyclohexanedimethanol, alicyclic diols such as tricyclodecane dimethanol, and xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxy) diphenylpropane, 2,2′-bis [4- (2-hydroxyethoxy) phenyl] propane, bis [4- (2-hydroxyethoxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane Aromatic diols such as 4,4′-dihydroxy-p-terphenyl and 4,4′-dihydroxy-p-quarterphenyl are preferred, and such diols are ester-forming derivatives such as acetyl compounds and alkali metal salts. It can also be used in the form.

  Two or more of these dicarboxylic acids, derivatives thereof, diol components and derivatives thereof may be used in combination. An example of a preferable high-melting crystalline polymer segment (a1) is a polybutylene terephthalate unit derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol. Also preferred are those comprising polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate and polybutylene isophthalate units derived from isophthalic acid and / or dimethyl isophthalate and 1,4-butanediol. It is done.

  The low melting point polymer segment (a2) of the polyester block copolymer (A) used in the present invention is an aliphatic polyether and / or an aliphatic polyester. Aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (trimethylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, and a combination of ethylene oxide and propylene oxide. And a polymer, an ethylene oxide addition polymer of poly (propylene oxide) glycol, a copolymer glycol of ethylene oxide and tetrahydrofuran, and the like. Examples of the aliphatic polyester include poly (ε-caprolactone), polyenanthlactone, polycaprylolactone, polybutylene adipate, and polyethylene adipate. From the elastic properties of the polyester block copolymers obtained from these aliphatic polyethers and / or aliphatic polyesters, poly (tetramethylene oxide) glycol, poly (propylene oxide) glycol ethylene oxide adducts, ethylene oxide and tetrahydrofuran Preferred are the use of copolymer glycols, poly (ε-caprolactone), polybutylene adipate, and polyethylene adipate, among which poly (tetramethylene oxide) glycol, poly (propylene oxide) glycol ethylene oxide adducts, and The use of a copolymer glycol of ethylene oxide and tetrahydrofuran is preferred. The number average molecular weight of these low-melting polymer segments is preferably about 300 to 6000 in the copolymerized state.

  The copolymerization amount of the low melting point polymer segment (a2) of the polyester block copolymer (A) used in the present invention is usually 5 to 90% by weight, preferably 7 to 85% by weight.

  The polyester block copolymer (A) used in the present invention can be produced by a known method. Specific examples thereof include, for example, a method of transesterifying a lower alcohol diester of a dicarboxylic acid, an excessive amount of a low molecular weight glycol and a low melting point polymer segment component in the presence of a catalyst, and polycondensing the resulting reaction product, and Any method such as a method in which a dicarboxylic acid, an excess amount of glycol and a low melting point polymer segment component are esterified in the presence of a catalyst and the resulting reaction product is polycondensed may be used. In order to improve the viscosity of the resin, it is of course desirable to perform solid phase polymerization after melt polymerization.

  Examples of such commercially available polyester elastomers include “Primalloy” manufactured by Mitsubishi Chemical Corporation, “Perprene” manufactured by Toyobo Co., Ltd., “Hytrel” manufactured by Toray DuPont Co., Ltd., and the like.

  The dynamically crosslinked thermoplastic elastomer composition (B) used in the present invention comprises 10 to 50% by weight of the polyalkylene phthalate polyester polymer and / or copolymer (b1) and 50 to 90% by weight of the crosslinked polymer. A mixture of at least one (co) polymer (b2) selected from possible poly (meth) acrylate, (meth) acrylate copolymer, polyethylene / (meth) acrylate copolymer is used as a radical generator. It is dynamically cross-linked when melt-mixed in an extruder in the presence.

  In this case, if the polyalkylene phthalate polyester (co) polymer (b1) is less than 10% by weight, the polyalkylene phthalate polyester (co) polymer does not become a continuous phase, and thermal processability such as injection molding or extrusion molding is not achieved. This is not preferable because it is significantly reduced. Further, if the polyalkylene phthalate polyester (co) polymer (b1) exceeds 50% by weight, the balance of hot water resistance, weather resistance, heat resistance and flexibility is unfavorable.

  A known method can be used for dynamic crosslinking of the polyalkylene phthalate polyester (co) polymer (b1) and the (co) polymer (b2). Examples of the method for forming this dynamically crosslinked thermoplastic elastomer (B) include polyalkylene phthalate polyester (co) polymer (b1), (co) polymer (b2), and radicals as an appropriate amount of a crosslinking agent. Generators such as 2,5-dimethyl-2,5- (t-butylperoxy) hexyne-3, 2,5-dimethyl-2,5- (t-butylperoxy) hexane, t-butylperoxybenzo And crosslinking aids such as diethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, N, N′-m-phenylene dimaleimide, triallyl isocyanate, and the like, and Antioxidants such as n-octadecyl-3- (3 ′, 5′-di-t- Butyl-4′-hydroxyphenyl) -propionate, n-octadecyl-3- (3′-methyl-5′-t-butyl-4′-hydroxyphenyl) -propionate, n-tetradecyl-3- (3 ′, 5 '-Di-t-butyl-4'-hydroxyphenyl) -propionate, 1,6-hexanediol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) -propionate], 1 , 4-Butanediol-bis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) -propionate], triethylene glycol-bis- [3- (3-tert-butyl-5-methyl) -4-hydroxyphenyl) -propionate], 2,2'-methylenebis- (4-methyl-t-butylphenol), tetrakis [methylene-3- (3 ' 5′-di-tert-butyl-4′-hydroxyphenyl) propionate] methane, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} — 1,1-dimethylethyl] 2,4,8,10-tetraoxaspiro (5,5) undecane, N, N′-bis-3- (3 ′, 5′-di-t-butyl-4′- Hydroxyphenyl) propionylhexamethylenediamine, N, N′-tetramethylene-bis-3- (3′-methyl-5′-t-butyl-4′-hydroxyphenol) propionyldiamine, N, N′-bis- [ 3- (3,5-di-tert-butyl-4-hydroxyphenol) propionyl] hydrazine, N-salicyloyl-N′-salicylidenehydrazine, 3- (N-salicyloyl) amino 1,2,4-triazole, N, N′-bis [2- {3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy} ethyl] oxyamide and the like, among them, particularly preferably Triethylene glycol-bis- [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) -propionate] and tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4 ′) -Hydroxyphenyl) propionate] A method of dynamically cross-linking a hindered phenol-based antioxidant such as methane with an extrusion molding machine or an injection molding machine can be used.

  The polyalkylene phthalate polyester or copolymer (b1) used in the dynamically crosslinked thermoplastic elastomer composition (B) used in the present invention is composed of a high-melting crystalline polymer segment (a1) and mainly a fat. Is a polyester block copolymer mainly composed of a low melting point polymer segment (a2) composed of an aromatic polyether unit and / or an aliphatic polyester unit, and the high melting point crystalline polymer segment (a1) is an aromatic Polyesters formed from dicarboxylic acids or their ester-forming derivatives and aliphatic diols, preferably polybutylene terephthalates derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol. And isophthalic acid, phthalic acid, naphthalene-2 Dicarboxylic acid components such as 1,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, or ester-forming derivatives thereof Diols having a molecular weight of 300 or less, for example, aliphatic diols such as ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol, 1,4-cyclohexanedimethanol, tricyclodecane dimethylol Such as alicyclic diol, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane, 2,2-bis [4- (2-hydroxyethoxy) phenyl] propane, bis [4- ( -Hydroxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane, 4,4′-dihydroxy-p-terphenyl, 4,4′-dihydroxy-p-quarterphenyl, etc. A polyester derived from an aromatic diol or the like, or a copolyester in which two or more of these dicarboxylic acid components and diol components are used in combination may be used. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, a polyfunctional oxyacid component, a polyfunctional hydroxy component, and the like in a range of 5 mol% or less.

  Two or more of these dicarboxylic acids and their derivatives or diol components may be used in combination. An example of a preferred high melting crystalline polymer segment is a polybutylene terephthalate unit derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol. Further, a polybutylene terephthalate unit derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, and a polybutylene terephthalate unit derived from isophthalic acid and / or dimethylisophthalate and 1,4-butanediol. Those composed of butylene isophthalate units are also preferably used.

  The low melting point polymer segment of the polyester block copolymer is an aliphatic polyether and / or an aliphatic polyester. Aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, copolymers of ethylene oxide and propylene oxide, poly (propylene oxide) Examples thereof include ethylene oxide addition polymers of glycol and copolymer glycols of ethylene oxide and tetrahydrofuran. Examples of the aliphatic polyester include poly (ε-caprolactone), polyenanthlactone, polycaprylolactone, polybutylene adipate, and polyethylene adipate. From the elastic properties of the polyester block copolymers obtained from these aliphatic polyethers and / or aliphatic polyesters, poly (tetramethylene oxide) glycol, poly (propylene oxide) glycol ethylene oxide adducts, ethylene oxide and tetrahydrofuran Preferred are the use of copolymer glycols, poly (ε-caprolactone), polybutylene adipate, and polyethylene adipate, among which poly (tetramethylene oxide) glycol, poly (propylene oxide) glycol ethylene oxide adducts, and The use of a copolymer glycol of ethylene oxide and tetrahydrofuran is preferred. The number average molecular weight of these low-melting polymer segments is preferably about 300 to 6000 in the copolymerized state.

  The copolymerization amount of the low melting point polymer segment in the polyester block copolymer used in the dynamically crosslinked thermoplastic elastomer composition (B) used in the present invention is preferably 15 to 90% by weight, more preferably It is in the range of 30 to 85% by weight.

  The (co) polymer (b2) used in the dynamically crosslinked thermoplastic elastomer (B) used in the present invention is an acrylic rubber, and the crosslinked product is one or more acrylic esters or methacrylic esters. Acid esters, and also copolymers of mixtures thereof, or linear copolymers formed from copolymers of ethylene and one or more acrylic or methacrylic esters or mixtures thereof. The acrylic rubber contains ethylene as a main component, and the acrylate can be cross-linked even at 6.5 mol%, but the acrylate is preferably 20 mol% or more from the viewpoint of compression set. In addition, poly (meth) acrylate and polyethylene / (meth) acrylate are linear copolymers that are inherently crosslinkable with organic peroxides and organic diene-based crosslinking aids, and in particular require a third monomer necessary for crosslinking. However, a crosslinking site monomer can be added as long as it does not affect the degree of crosslinking reached by dynamic crosslinking with a free radical initiator.

  The uncrosslinked acrylic rubber used in the dynamically crosslinked thermoplastic elastomer (B) used in the present invention is ethylene and one or more alkyl esters of acrylic acid, methacrylic acid or a mixture thereof, for example, alkyl acrylate. A copolymer of ˜60% by weight is preferred.

  The production method of the dynamically crosslinked thermoplastic elastomer (B) used in the present invention can be produced by a known method. For example, a thermoplastic resin component containing a polyalkylene phthalate polyester polymer and / or copolymer (b1) and a rubber component made of uncrosslinked acrylic rubber are melt-kneaded with a twin-screw kneading extruder or the like to obtain a continuous phase. The rubber component is dispersed as a dispersed phase (domain) in the thermoplastic resin forming the (matrix phase). Next, in order to cross-link the rubber component, a cross-linking agent (free radical generator) and an organic diene-based cross-linking aid are added under kneading to dynamically cross-link the rubber component. Further, various compounding agents for the thermoplastic resin or the rubber component may be added during the kneading, but it is preferable to premix them before kneading. At this time, a crosslinking agent may be mixed in advance in the rubber component, and vulcanization may be simultaneously performed while kneading the thermoplastic resin and the rubber component. The kneading machine used for kneading the thermoplastic resin and the rubber component is not particularly limited, and a screw extruder, a kneader, a Banbury mixer, a biaxial kneading extruder, or the like can be used. Among these, it is preferable to use a twin-screw kneading extruder for kneading the thermoplastic resin and the rubber component and for dynamic vulcanization of the rubber component. Further, two or more types of kneaders may be used and kneaded sequentially.

  The dynamically cross-linked thermoplastic elastomer (B) thus obtained has a fine vulcanized rubber phase at least partially in the thermoplastic resin phase that is at least partly a discontinuous phase. Since it is in a dispersed state, this dynamically crosslinked thermoplastic elastomer (B) exhibits the same behavior as the crosslinked rubber, and at least the continuous phase is a thermoplastic resin phase. Processing according to thermoplastic resin is possible. Commercially available products of such dynamically crosslinked thermoplastic elastomer (B) include “Du Pont ™ ETPV” manufactured by Du Pont.

  The blending ratio of the polyester block copolymer (A) and the dynamically crosslinked thermoplastic elastomer (B) is (A) / (B) of 65 to 5% by weight / 35 to 95% by weight, particularly 60 to 60%. It is preferable to be 10% by weight / 40 to 90% by weight. If (B) is less than the above range, the balance of heat resistance, flexibility and extrudability cannot be maintained at a high level, and exceeds the above range. This is not preferable because the fluidity is lowered and the extrudability is inferior.

  As the heat-resistant agent (C) used in the present invention, one kind selected from the group consisting of an aromatic amine-based antioxidant, a hindered phenol-based antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant, Or 2 or more types and / or a polyamide resin are mentioned.

  Specific examples of the aromatic amine antioxidant include phenylnaphthylamine, 4,4′-dimethoxydiphenylamine, 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, and 4-isopropoxydiphenylamine. However, among these, the use of diphenylamine compounds is preferred.

  Specific examples of hindered phenol antioxidants include 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, hydroxy Methyl-2,6-di-t-butylphenol, 2,6-di-t-α-dimethylamino-p-cresol, 2,5-di-t-butyl-4-ethylphenol, 4,4′- Bis (2,6-di-t-butylphenol), 2,2'-methylene-bis-4-methyl-6-t-butylphenol, 2,2'-methylene-bis (4-ethyl-6-t-butylphenol) ), 4,4′-methylene-bis (6-t-butyl-o-cresol), 4,4′-methylene-bis (2,6-di-t-butylphenol), 2,2′-methylene-bis (4-Methyl-6- Chlorylphenol), 4,4′-butylidene-bis (3-methyl-6-tert-butylphenol), 4,4′-thiobis (6-tert-butyl-3-methylphenol), bis (3-methyl-) 4-hydroxy-5-t-butylbenzyl) sulfide, 4,4′-thiobis (6-t-butyl-o-cresol), 2,2′-thiobis (4-methyl-6-t-butylphenol), 2 , 6-Bis (2′-hydroxy-3′-tert-butyl-5′-methylbenzyl) -4-methylphenol, diethyl ester of 3,5-di-tert-butyl-4-hydroxybenzenesulfonic acid, 2 , 2′-dihydroxy-3,3′-di (α-methylcyclohexyl) -5,5′-dimethyl-diphenylmethane, α-octadecyl-3 (3 ′, 5′-di-t-butyl-4 -Hydroxyphenyl) propionate, 6- (hydroxy-3,5-di-t-butylanilino) -2,4-bis-octyl-thio-1,3,5-triazine, hexamethylene glycol-bis [β- (3 , 5-di-tert-butyl-4-hydroxyphenol) propionate], N, N′-hexamethylene-bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid amide), 2,2- Thio [diethyl-bis-3 (3,5-di-t-butyl-4-hydroxyphenyl) propionate], dioctadecyl ester of 3,5-di-t-butyl-4-hydroxybenzenephosphonic acid, tetrakis [methylene -3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 1,3,5-trimethyl-2,4,6-tris ( , 5-di-t-butyl-4-hydroxybenzyl) benzene, 1,1,3-tris (2-methyl-4-hydroxy-5-di-t-butylphenyl) butane, tris (3,5-di-) -T-butyl-4-hydroxyphenyl) isocyanurate, tris [β- (3,5-di-t-butyl-4hydroxyphenyl) propionyl-oxyethyl] isocyanurate, and the like. Among these, the use of those having a molecular weight of 500 or more such as tetrakis [methylene-3 (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane is preferable.

  The sulfur-based antioxidant is a compound containing sulfur such as thioether, dithioate, mercaptobenzimidazole, thiocarbanilide, and thiodipropion ester. Among these, the use of a thiodipropion ester-based compound is particularly preferable.

  The phosphorus-based antioxidant is a compound containing phosphorus such as phosphoric acid, phosphorous acid, hypophosphorous acid derivative, phenylphosphonic acid, polyphosphonate, dialkylpentaerythritol diphosphite, and dialkylbisphenol A diphosphite. Among these, it is preferable to use a compound having a sulfur atom in the molecule and a compound having two or more phosphorus atoms in the molecule.

  Polyamide resin is a polymer compound having an amide bond in the molecular chain, and is a polymer from lactam, adipic acid, sebacic acid, dodecanedioic acid, etc., and ethylenediamine, hexamethylenediamine, metaxylenediamine, etc. Examples thereof include a polymer of a salt obtained by the reaction or a polymer from ω-aminocarboxylic acid. These polyamide resins may be copolymers, or two or more different polymers may be used in combination. Among these polyamide resins, when nylon 6 and / or binary or ternary or higher copolymer polyamide resin is used, even higher effects can be obtained.

  The total amount of these heat-resistant agents (C) is 100 parts by weight of the thermoplastic elastomer composition obtained by mixing the polyester block copolymer (A) and the dynamically crosslinked thermoplastic elastomer composition (B). On the other hand, it is 0.01-10 weight part, Preferably it is 0.05-7 weight part, More preferably, it is 0.1-5 weight part.

  When the total amount of the heat-resistant agent (C) is less than 0.01 part by weight, the degree of obtaining the desired improvement effect is small, and when it exceeds 10 parts by weight, blooming occurs or the mechanical strength of the thermoplastic elastomer It is not preferable because it lowers

  The thermoplastic elastomer composition obtained by mixing the polyester block copolymer (A) of the present invention and the dynamically crosslinked thermoplastic elastomer composition (B) further includes a polycarbonate resin (D) and / or a polyphenylene ether. By adding the resin (E), heat resistance, strength / rigidity, workability, heat shrinkage characteristics and the like can be balanced at a higher level.

  The polycarbonate resin (D) is a known polycarbonate resin, preferably an aromatic polycarbonate resin, more preferably an aromatic polycarbonate resin obtained by a reaction between a dihydric phenol and a carbonate precursor. These can be obtained by a known polymerization method such as a solution method or a melting method.

  The dihydric phenol is, for example, bisphenol A or a bis (4-hydroxyphenyl) alkane compound, and preferably bisphenol A, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1 , 1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis ( 4-hydroxy-3-methylphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, and the like. Particularly preferred is bisphenol A. A dihydric phenol can be used individually or in mixture of 2 or more types.

  The carbonate precursor is, for example, carbonyl halide, carbonate, haloformate, and representative examples include phosgene, diphenyl carbonate, dinaphthyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl. And carbonates, dinaphthyl carbonates, dihaloformates of dihydric phenols, and mixtures thereof.

  Moreover, a suitable molecular weight regulator, a branching agent, a catalyst, etc. can be used in the production of the aromatic carbonate.

  The compounding amount of the polycarbonate resin (D) is based on 100 parts by weight of the thermoplastic elastomer composition obtained by mixing the polyester block copolymer (A) and the dynamically crosslinked thermoplastic elastomer composition (B). 0 to 25 parts by weight, preferably 0 to 20 parts by weight. When the blending amount of the polycarbonate resin (D) exceeds 25 parts by weight, the flexibility and rubber elasticity inherent in the thermoplastic elastomer are impaired, which is not preferable.

  Specifically, the polyphenylene ether resin (E) is poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl 1,4-phenylene) ether, poly (2,6- Examples include dipropyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, and poly (2-methyl-6-propyl-1,4-phenylene) ether. In particular, poly (2,6-dimethyl-1,4-phenylene) ether, 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, and a graft copolymer obtained by graft polymerization of styrene to these. preferable. Moreover, the modified polyphenylene ether obtained by making this polyphenylene ether react with unsaturated aliphatic carboxylic acid or its acid anhydride can also be used.

  The blending amount of the polyphenylene ether resin (E) is based on 100 parts by weight of the thermoplastic elastomer composition obtained by mixing the polyester block copolymer (A) and the dynamically crosslinked thermoplastic elastomer composition (B). 0 to 25 parts by weight, preferably 0 to 20 parts by weight. When the blending amount of the polyphenylene ether resin (F) exceeds 25 parts by weight, the inherent flexibility and rubber elasticity of the thermoplastic elastomer are impaired, which is not preferable.

  Furthermore, in addition to the additives (C) to (E), various additives can be added to the heat-resistant thermoplastic elastomer resin composition of the present invention as long as the object of the present invention is not impaired. For example, molding aids such as known crystal nucleating agents and lubricants, UV absorbers and hindered amine-based light-proofing agents, hydrolysis-proofing agents, colorants such as pigments and dyes, antistatic agents, conductive agents, halogen-based Flame retardants such as phosphorus-based and metal hydrates, reinforcing materials such as glass fibers and carbon fibers, fillers such as mineral particles, plasticizers, mold release agents such as wax, and the like can be optionally contained.

  Although the manufacturing method of the thermoplastic elastomer resin composition of the present invention is not particularly limited, for example, the polyester block copolymer (A) and the dynamically crosslinked thermoplastic elastomer composition (B) are predetermined. A heat-resistant agent (C), a polyester block copolymer (A), a dynamically crosslinked thermoplastic elastomer composition (B), a predetermined heat-resistant agent (C), a polycarbonate resin (D), and The raw material blended with the polyphenylene ether resin (E) is supplied to a screw-type extruder and melt-kneaded. The screw-type extruder is first fed with a polyester block copolymer (A) and heat dynamically crosslinked. The plastic elastomer composition (B) is supplied and melted, and the heat-resistant agent (C) and other compound are supplied and kneaded from another supply port, and further supplied. It can be adopted as appropriate methods of feeding kneading more polycarbonate resin (D) and / or polyphenylene ether resin (E).

  Moreover, as a manufacturing method of the heat-shrinkable tube of this invention, the method of extruding an unstretched tube using a ring die and then extending | stretching to make a heat-shrinkable tube is mentioned as a preferable method. In addition, there are a method in which a sheet extruded and stretched using a T die or an I die is bonded by fusing, welding, or bonding to form a tube, and a method in which the sheet is bonded in a spiral to form a tube. .

  Here, a method for extruding an unstretched tube using a ring die and then stretching it into a heat-shrinkable tube will be described in more detail. The above heat-resistant thermoplastic elastomer resin composition is heated and melted to a temperature equal to or higher than the melting point by a melt extruder, continuously extruded from a ring die, and then forcibly cooled and formed into an unstretched tube. As a means for forced cooling, a method of immersing in low-temperature water, a method using cooling air, or the like can be used. Among them, the method of immersing in low-temperature water is effective because of high cooling efficiency. This unstretched tube may be continuously supplied to the next stretching step, or once wound into a roll, the unstretched roll may be used as a raw material for the next stretching step. From the viewpoint of production efficiency and thermal efficiency, a method of continuously supplying an unstretched tube to the next stretching step is preferable.

  The unstretched tube thus obtained is pressurized with compressed gas from the inside of the tube and biaxially stretched. The stretching method is not particularly limited, but, for example, it is sent out from one end of an unstretched tube at a constant speed while applying pressure by a compressed gas to the inside of the tube, and then preheated with hot water or an infrared heater, etc. Biaxial stretching is performed in a stretching tube heated to a stretching temperature that regulates the stretching ratio. Temperature conditions and the like are set so that the film is drawn at an appropriate position on the drawing pipe. It cools after extending | stretching, and is taken up and wound up as an extending | stretching tube, hold | maintaining extending | stretching pressure by pinching with a pair of nip rolls. Stretching may be performed in any order in the length direction or the radial direction, but is preferably performed simultaneously.

  The stretching ratio in the length direction is determined by the ratio of the feed speed of the unstretched tube and the nip roll speed after stretching, and the stretching ratio in the radial direction is determined by the ratio of the unstretched outer diameter to the stretched tube outer diameter. As another stretching and pressurizing method, a method of maintaining the internal pressure of the compressed gas in which both the unstretched tube feed side and the stretched tube take-up side are sandwiched and sealed between nip rolls can be employed.

  The heat-shrinkable tube molded body thus obtained is preferably applied because of its excellent hardness, strength / rigidity, and heat resistance.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to these examples, and can be implemented with appropriate modifications within the scope of the gist of the present invention.

  In the following examples, “parts” and “%” indicate weight units unless otherwise specified.

  Moreover, evaluation of the heat aging resistance and extrusion moldability of the heat-shrinkable tube comprising the heat-resistant thermoplastic elastomer resin composition in the following examples was performed by the following methods.

[Heat aging resistance]
After the heat-resistant thermoplastic elastomer composition pellets of the present invention have been hot-air dried at 90 ° C. for 3 hours or more, the outer diameter is measured by using water-cooled vacuum sizing at a temperature of 200 to 240 ° C. using a φ30 single screw extruder. An unstretched tube having a diameter of 10 mm and an inner diameter of 9 mm was formed. This unstretched tube was introduced into a 95 ° C. hot water bath, and a stretched tube having an inner diameter of 16 mmφ was stretched while applying an internal pressure to the tube with compressed air to obtain a stretched heat-shrinkable tube. An aluminum pipe pipe having an outer diameter of 16 mm was inserted into this stretched heat-shrinkable tube, left in a hot air oven at 160 ° C. for 500 hours, then taken out, cut out with a cutter and the like, and a small test piece was obtained by punching out a JIS K 7113 small test piece. . The punched small test piece was measured for tensile properties according to JIS K 7113, and evaluated with a rank of ○: tensile elongation at break of 50% or more and x: tensile elongation at break of less than 50%.

[Extrudability]
After the heat-resistant thermoplastic elastomer composition pellets of the present invention have been hot-air dried at 90 ° C. for 3 hours or more, the outer diameter is measured by using water-cooled vacuum sizing at a temperature of 200 to 240 ° C. using a φ30 single screw extruder. An unstretched tube having a diameter of 10 mm and an inner diameter of 9 mm was formed. This unstretched tube was introduced into a 95 ° C. warm water bath, and a stretched tube having an inner diameter of 16 mmφ was stretched while applying an internal pressure to the tube with compressed air to obtain a stretched heat-shrinkable tube. The wall thickness of this stretched heat-shrinkable tube molded product was measured.
(Circle): The tube thickness deviation amount was 0.1 mm or less, x: The tube thickness deviation amount evaluated in the rank over 0.1 mm.

[Production of polyester block copolymer (A-1)]
302 parts of terephthalic acid, 327 parts of 1,4-butanediol and 216 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400 are placed in a reaction vessel equipped with a helical ribbon stirring blade together with 0.15 part of titanium tetrabutoxide. The esterification reaction was carried out while charging the reaction water at 190 to 225 ° C. for 3 hours and distilling the reaction water out of the system. After adding 0.75 part of “Irganox” 1010 (a hindered phenol antioxidant manufactured by Ciba Geigy Co., Ltd.) to the reaction mixture, the temperature was raised to 245 ° C. The pressure was reduced to 2 mmHg, and polymerization was performed for 2 hours and 45 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and cut into pellets. The removed pellet was then subjected to solid phase polymerization.

[Production of polyester block copolymer (A-2)]
348 parts of terephthalic acid, 340 parts of 1,4-butanediol and 645 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400, together with 0.15 part of titanium tetrabutoxide, are placed in a reaction vessel equipped with a helical ribbon stirring blade. The esterification reaction was carried out while charging the reaction water at 190 to 225 ° C. for 3 hours and distilling the reaction water out of the system. After adding 0.75 part of “Irganox” 1010 (a hindered phenol antioxidant manufactured by Ciba Geigy Co., Ltd.) to the reaction mixture, the temperature was raised to 245 ° C. The pressure was reduced to 2 mmHg, and polymerization was performed for 2 hours and 45 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and cut into pellets. The removed pellet was then subjected to solid phase polymerization.

[Production of Polyester Block Copolymer (A-3)]
384 parts of terephthalic acid, 416 parts of 1,4-butanediol, and 101 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1000 are placed in a reaction vessel equipped with a helical ribbon type stirring blade together with 0.15 part of titanium tetrabutoxide. The esterification reaction was performed while charging and heating the reaction water at 190 to 230 ° C. for 3 hours to distill the reaction water out of the system. After adding 0.75 part of “Irganox” 1010 (a hindered phenol antioxidant manufactured by Ciba Geigy Co., Ltd.) to the reaction mixture, the temperature was raised to 245 ° C. The pressure was reduced to 2 mmHg, and polymerization was performed for 2 hours and 45 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and cut into pellets. The removed pellet was then subjected to solid phase polymerization.

  Table 1 shows the compositions and physical properties of the polymers A-1, A-2, and A-3 thus obtained.

[Production of Dynamically Crosslinked Thermoplastic Elastomer (B-1)]
100 parts of a polyethylene / acrylate elastomer (for example, Baymac manufactured by DuPont) obtained by copolymerizing ethylene and 63% by weight of methyl acrylate is quantitatively fed to the front stage of a twin screw extruder having a 45 mmφ screw, It knead | mixed under the temperature of 100-130 degreeC. Thereafter, 2.9 parts of a crosslinking agent (peroxide crosslinking agent: for example, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexyne-3) and an auxiliary agent (organic diene-based crosslinking auxiliary agent: For example, 4.3 parts of dimethylene glycol dimethacrylate) was quantitatively added to a twin screw extruder by a pump. Next, 33 parts of the polyester block copolymer (A-1) and “Irganox” 1010 (Cinder Geigy's hindered phenol-based oxidation were added to the middle part of the twin-screw extruder whose temperature was raised to 240 to 250 ° C. Inhibitor) While blending 0.5 parts of a blend blended in advance with a feeder into a twin-screw extruder quantitatively, mixing with the polyethylene / acrylate elastomer melt kneaded in the previous stage, The acrylate elastomer was crosslinked and simultaneously kneaded and dispersed strongly at the subsequent stage. Further, after the devolatilization treatment at the last step part, it was discharged from the extruder through a three-hole strand die, cut with water and then cut into pellets.

  The dynamically crosslinked thermoplastic elastomer composition thus obtained had a melting point of 207 ° C. and a hardness of 60A.

[Production of Dynamically Crosslinked Thermoplastic Elastomer (B-2)]
100 parts of a polyethylene / acrylate elastomer (for example, Baymac manufactured by DuPont) obtained by copolymerizing ethylene and 63% by weight of methyl acrylate is quantitatively fed to the front stage of a twin screw extruder having a 45 mmφ screw, It knead | mixed under the temperature of 100-130 degreeC. Thereafter, 2.9 parts of a crosslinking agent (peroxide crosslinking agent: for example, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexyne-3) and an auxiliary agent (organic diene-based crosslinking auxiliary agent: For example, 4.3 parts of dimethylene glycol dimethacrylate) was quantitatively added to a twin screw extruder by a pump. Next, 100 parts of a polyester block copolymer (A-3) and “Irganox” 1010 (Ciba Geigy's hindered phenol-based oxidation) were added to the middle stage of the twin-screw extruder whose barrel temperature was raised to 240 to 250 ° C. Inhibitor) While blending 0.5 parts of a blend blended in advance with a feeder into a twin-screw extruder quantitatively, mixing with the polyethylene / acrylate elastomer melt kneaded in the previous stage, The acrylate elastomer was crosslinked and simultaneously kneaded and dispersed strongly at the subsequent stage. Further, after the devolatilization treatment at the last step part, it was discharged from the extruder through a three-hole strand die, cut with water and then cut into pellets.

  The dynamically crosslinked thermoplastic elastomer composition thus obtained had a melting point of 215 ° C. and a hardness of 95A.

[Heat-resistant agent]
Table 2 shows the abbreviations and structural formulas of the antioxidants (C-1), (C-2), (C-3), (C-4) and (C-5) used in the following examples. Further, a copolymer (polyamide resin (C-6)) having a composition ratio of polycaprolactam and polyhexamethylene adipamide of about 65/35, and polycaprolactam, polyhexamethylene adipamide and polyhexamethylene sebaca A terpolymer (polyamide resin (C-7)) having an amide composition ratio of about 45/35/20 was produced.

  Furthermore, Amilan CM1016 manufactured by Toray Industries, Inc. was used as the polyamide resin (C-8).

[Polycarbonate resin]
Iupilon S-2000R manufactured by Mitsubishi Engineering Plastics Co., Ltd. was used as the polyester resin (D-1).

[Polyphenylene ether resin]
As polyphenylene ether resin (E-1), Xylon X9108 manufactured by Asahi Kasei Chemical Co., Ltd. was used.

(Examples 1 to 11)
Polyether ester block copolymers (A-1), (A-2) and (A-3) obtained in Reference Examples, and dynamically crosslinked thermoplastic elastomer compositions (B-1) and (B -2), heat-resistant agent (C) and polycarbonate resin (D-1) and / or polyphenylene ether resin (E-1) are all dry blended at a blending ratio as shown in Table 3, and a 45 mmφ screw is used. Using a twin screw extruder, the mixture was melt kneaded at a temperature setting of 220 ° C. to 240 ° C. and then pelletized. The pellet was dried at 80 ° C. for 6 hours to obtain a thermoplastic elastomer pellet. Using this thermoplastic elastomer pellet, heat aging resistance and extrusion moldability were evaluated under predetermined conditions. These results are shown in Table 3.

(Comparative Examples 1-10)
Polyether ester block copolymers (A-1), (A-2) and (A-3) obtained in Reference Examples, and dynamically crosslinked thermoplastic elastomer compositions (B-1) and (B The raw material of the resin composition of -2) was dry blended at each blending ratio shown in Table 3, and pelletized in the same manner as in Example 1. These pellets, polyester block copolymers (A-1), (A-2) and (A-3) obtained in Reference Examples, and dynamically crosslinked thermoplastic elastomer composition (B-1) , (B-2) itself was molded under the same conditions as in the Examples and evaluated in the same manner. These results are also shown in Table 3.

  As is apparent from the results in Table 3, a heat resistant agent (aromatic amine antioxidant, hindered phenol) is added to a thermoplastic elastomer obtained by mixing a polyester block copolymer and a dynamically crosslinked thermoplastic elastomer composition. A heat-resistant thermoplastic elastomer resin composition of the present invention (Examples 1, 2, 5 to 11) containing at least one of a antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant and / or a polyamide resin) Is excellent in extrusion moldability and heat aging resistance of a heat-shrinkable tube made of the same. In addition, a thermoplastic elastomer formed by mixing a polyester block copolymer and a dynamically crosslinked thermoplastic elastomer composition is added with a heat-resistant agent (aromatic amine-based antioxidant, hindered phenol-based antioxidant, sulfur-based oxidation). The heat-resistant thermoplastic elastomer resin composition (Examples 3 and 4) of the present invention, which is blended with one or more of an antioxidant, a phosphorus-based antioxidant and / or a polyamide resin) and further a polycarbonate resin and / or a polyphenylene ether resin, In addition to being excellent in extrusion moldability, the heat-shrinkable tube made therefrom is also excellent in heat aging resistance.

  On the other hand, the resin compositions of Comparative Examples 1 to 10 that do not satisfy the conditions of the present invention and the heat-shrinkable tube made of the same are compared with the resin compositions of the present invention and the heat-shrinkable tube made of the present invention. Any or all of them are inferior.

  The heat-shrinkable tube comprising the heat-resistant thermoplastic elastomer resin composition of the present invention has sufficient heat resistance and extrudability as a heat-shrinkable tube as described above, so that it is particularly flexible for automobile parts, electrical equipment, industrial products, etc. It is also suitable for heat shrinkable tube products that require heat resistance.

  In particular, the heat-shrinkable tube molded body made of the heat-resistant thermoplastic elastomer resin composition of the present invention has both flexibility and a heat-resistant life that is longer than conventional ones, and thus can be widely applied in automobiles, electrical equipment, and industrial applications. .

Claims (7)

The main component is a high-melting-point crystalline polymer segment (a1) mainly composed of a crystalline aromatic polyester unit and a low-melting-point polymer segment (a2) mainly composed of an aliphatic polyether unit and / or an aliphatic polyester unit. Polyester block copolymer (A) 65 to 5% by weight, polyalkylene phthalate polyester polymer and / or copolymer (b1) 10 to 50% by weight and crosslinkable poly (meth) acrylate, (meth) acrylate A mixture of at least one (co) polymer (b2) 50 to 90% by weight selected from a copolymer and a polyethylene / (meth) acrylate copolymer in an extruder in the presence of a radical generator. When melt-mixing, 35 to 95% by weight of dynamically crosslinked thermoplastic elastomer (B) is mixed. The thermoplastic elastomer composition 100 parts by weight, heat stabilizers (C) heat-shrinkable tube molded body characterized by comprising a heat thermoplastic elastomer resin composition obtained by blending 0.01 to 10 parts by weight. 2. The thermoplastic elastomer composition according to claim 1, further comprising 0 to 25 parts by weight of a polycarbonate resin (D) and / or 0 to 25 parts by weight of a polyphenylene ether resin (E), based on 100 parts by weight of the thermoplastic elastomer composition. The heat-shrinkable tube molded article as described. The weight ratio of the high-melting crystalline polymer segment (a1) and the low-melting polymer segment (a2) of the polyester block copolymer (A) is 30/70 to 95/5. Or the heat shrinkable tube molded object of 2. The polyalkylene phthalate polyester polymer and / or copolymer (b1) is selected from polyalkylene terephthalate, polyalkylene terephthalate copolymer, polyalkylene isophthalate polyether ester and polyalkylene terephthalate copolymer polyether ester. The heat-shrinkable tube molded body according to any one of claims 1 to 3, wherein the heat-shrinkable tube molded body is at least one kind. At least one (co) polymer (b2) selected from the dynamically cross-linked poly (meth) acrylate, (meth) acrylate copolymer, and polyethylene / (meth) acrylate copolymer is a polyacrylate elastomer. The heat-shrinkable tube molded body according to any one of claims 1 to 4, wherein the heat-shrinkable tube molded body is a polyethylene acrylate elastomer. The heat-resistant agent (C) is one or more selected from the group consisting of an aromatic amine-based antioxidant, a hindered phenol-based antioxidant, a sulfur-based antioxidant and a phosphorus-based antioxidant, and / or Alternatively, the heat-shrinkable tube molded body according to any one of claims 1 to 5, which is made of a polyamide resin. The heat-shrinkable tube molded article according to any one of claims 1 to 6, wherein the heat-shrinkable tube molded article is produced by extruding the heat-resistant thermoplastic elastomer resin composition.