KR102238921B1 - Thermoplastic elastomer resin composition and molding - Google Patents

Abstract

[Problem] Provided is a thermoplastic elastomer resin composition that is flexible, has little bleed-out, has little gas generated during formation, has excellent mold release from the mold, has good appearance of molded products, and has few burrs in molded products.
[Solution] Polyether ester block copolymer (A) comprising as constituent components a high melting point crystalline polymer segment (a1) consisting of crystalline aromatic polyester and a low melting point polymer segment (a2) consisting of aliphatic polyether units. 80% by weight, 10-50% by weight of a thermoplastic elastomer in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin (B), and a graft copolymer obtained by graft polymerization of a vinyl-based monomer in a rubbery polymer (C) 10 Thermoplastic elastomer resin composition comprising ~ 50% by weight.

Description

Thermoplastic elastomer resin composition and molded article TECHNICAL FIELD

The present invention relates to a thermoplastic elastomer resin composition. In particular, the present invention is flexible, has less bleed-out, less gas generated during molding, has excellent releasability from the mold of the molded product, has excellent molded product appearance, has fewer burrs of the molded product, and mechanically It relates to a thermoplastic elastomer resin composition having high physical properties and excellent heat-sealing property with a hard resin. Further, the present invention relates to a molded article using a thermoplastic elastomer resin composition.

A polyester block copolymer in which a crystalline aromatic polyester unit such as a polybutylene terephthalate unit is used as a hard segment and an aliphatic polyether unit such as poly(alkylene oxide) glycol is used as a soft segment. It has high mechanical properties, and is a molding material excellent in many properties such as high temperature properties, low temperature properties, oil resistance and chemical resistance. Since the polyester block copolymer has a good balance of these properties, its use has been expanded to automobile parts and electric/electronic parts.

However, there is a limit to further softening of the polyester block copolymer while maintaining the characteristics of the polyester block copolymer, and there is a limit to the development of its use.

Therefore, as an attempt to maintain and soften the characteristics of the polyester block copolymer, a resin composition comprising a styrene-based hydrogenated block copolymer and a polyester-based thermoplastic elastomer (for example, see Patent Document 1) and a styrene-based elastomer A resin composition comprising a dynamic crosslinked styrene-based elastomer and a polyester-based thermoplastic elastomer obtained by dynamically crosslinking a thermoplastic elastomer made of is proposed (for example, see Patent Document 2).

On the other hand, in order to maintain and soften the characteristics of the polyester block copolymer, the core-shell copolymer and polyester are copolymerized with a core polymer mainly composed of butyl acrylate and a polymer mainly composed of styrene and acrylonitrile as a shell. A resin composition composed of a thermoplastic elastomer (for example, see Patent Document 3) or a polymer mainly composed of styrene and acrylonitrile as shells is copolymerized with a hydrogenated styrene block copolymer and a core polymer mainly composed of butyl acrylate. A resin composition comprising a core-shell copolymer and a polyester-based thermoplastic elastomer (for example, see Patent Document 4) has been proposed.

The resin composition disclosed in Technical Document 1 can reliably obtain a flexible resin composition compared to the conventional polyester block copolymer. However, there is a problem that the releasability at the time of injection molding is deteriorated due to stickiness of the surface, and the appearance of the surface of the molded article is deteriorated by bleeding out, for example, paraffin oil added as a softening agent. In addition, the resin composition disclosed in Technical Literature 2 and Technical Literature 3 has good releasability during injection molding. However, there is a problem in that there is a lot of gas generated during injection molding, and the surface appearance of the injection-molded product is deteriorated. In addition, the resin composition disclosed in Technical Document 4 has good releasability during injection molding, and has good surface appearance of a molded article. However, there is a problem in that burrs are liable to occur in the injection molded article.

Japanese Patent Laid-Open No. Hei 10-130451 Japanese Patent Publication No. 2000-302940 Japanese Patent Publication No. 2004-190016 Japanese Patent Publication No. 2010-222467

The present invention aims at solving the problems in the prior art described above. The object of the present invention is excellent in flexibility, less bleed out, less gas generated during injection molding, excellent releasability from the mold, good appearance of molded products, and burrs of molded products. It is to provide a resin composition with less occurrence of burr).

The inventors of the present invention have come to the present invention as a result of earnestly examining in order to achieve the above object.

That is, the present invention is a polyether ester block copolymer (A) comprising a high melting point crystalline polymer segment (a1) composed of crystalline aromatic polyester and a low melting point polymer segment (a2) composed of aliphatic polyether units as constituent components. -80% by weight, 10-50% by weight of a thermoplastic elastomer in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin (B), a graft copolymer obtained by graft polymerization of a vinyl-based monomer in a rubbery polymer (C) It is a thermoplastic elastomer resin composition containing 10 to 50% by weight.

(Effects of the Invention)

The polyester-based elastomer resin composition of the present invention has excellent flexibility, less bleed out, less gas generated during injection molding, excellent release from the mold, good appearance of molded products, and It is possible to obtain a thermoplastic elastomer resin composition having few burrs, high mechanical properties, and excellent adhesion to hard resins.

The thermoplastic elastomer resin composition of the present invention is flexible, has little bleed out, less gas generated during molding, has excellent mold release, has good appearance of molded products, and has good burr of molded products. It is very useful because it is small.

1 is a plan view (1) and a side view (2) showing the schematic shape of a test piece of a heat fusion test with a hard resin in Examples and Comparative Examples.
Fig. 2 is a side view showing a schematic shape when thermally fused in Examples and Comparative Examples.
3 is a side view showing a schematic shape for measuring heat-sealing adhesion in Examples and Comparative Examples.
4 is a plan view (3) and a side view (4) showing schematic diagrams for measuring the amount of burrs generated in Examples and Comparative Examples.

Hereinafter, the present invention will be described in detail.

The high melting point crystalline polymer segment (a1) of the polyether ester block copolymer (A) used in the present invention is a polyester formed of 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, anthracenedicarboxylic acid, diphenyl-4,4' -Dicarboxylic acid, diphenoxyethane dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid and sodium 3-sulfoisophthalate, and the like are exemplified. The aromatic dicarboxylic acid is preferably terephthalic acid and isophthalic acid. If necessary, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, and 4,4'-dicyclohexyldicarboxylic acid may be used as part of the aromatic dicarboxylic acid. However, they may be substituted with aliphatic dicarboxylic acids such as adipic acid, succinic acid, oxalic acid, sebacic acid, dodecanedioic acid and dimer acid. Further, if necessary, a part of the aromatic dicarboxylic acid may be substituted with an ester-forming derivative of a dicarboxylic acid such as a lower alkyl ester, an aryl ester, a carbonate ester, an acid halide, or the like. These dicarboxylic acids and their derivatives may be used in combination of two or more.

Examples of diols include diols having a molecular weight of 400 or less, such as 1,4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, and aliphatic diols such as decamethylene glycol, and 1,1-cyclohexane. Alicyclic diols such as dimethanol, 1,4-dicyclohexanedimethanol, tricyclodecanedimethanol, xylylene glycol, bis(p-hydroxy)diphenyl, bis(p-hydroxyphenyl)propane, 2 ,2-bis[4-(2-hydroxyethoxy)phenyl]propane, bis[4-(2-hydroxy)phenyl]sulfone, 1,1-bis[4-(2-hydroxyethoxy)phenyl ] Aromatic diols, such as cyclohexane, 4,4'-dihydroxy-p-terphenyl, and 4,4'-dihydroxy-p-quaterphenyl, are preferable. The diol can also be used in the form of an ester-forming derivative such as an acetyl compound or an alkali metal salt. The diol is preferably 1,4-butanediol. These diol components may be used in combination of two or more.

The high melting point crystalline polymer segment (a1) of the polyether ester block copolymer (A) is more preferably composed of a polybutylene terephthalate unit or a polybutylene terephthalate unit and a polybutylene isophthalate unit.

The low melting point polymer segment (a2) of the polyether ester block copolymer (A) used in the present invention is an aliphatic polyether. Aliphatic polyethers include poly(ethylene oxide) glycol, poly(propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(hexamethylene oxide) glycol, a copolymer of ethylene oxide and propylene oxide, and poly An ethylene oxide adduct of (propylene oxide) glycol, a copolymer of ethylene oxide and tetrahydrofuran, etc. are illustrated. The low melting point polymer segment (a2) of the polyether ester block copolymer (A) is preferably poly(tetramethylene oxide) glycol, an ethylene oxide adduct of poly(propylene oxide) glycol, and ethylene oxide and tetra It is a copolymer glycol of hydrofuran, and may be used alone, or a plurality of mixtures may be used.

As the polyether ester block copolymer (A) used in the present invention, two or more types of polyether ester block copolymers of different compositions may be used in combination.

The copolymerization amount of the low melting point polymer segment (a2) of the polyether ester block copolymer (A) used in the present invention is preferably 15 to 90% by weight, more preferably 30 to 80% by weight. Particularly, at 15% by weight or less, flexibility is insufficient, and at 90% by weight or more, crystallinity is low, and moldability tends to be inferior.

The polyether ester block copolymer (A) used in the present invention can be produced by a known method. For example, a method of polycondensing a reaction product obtained by transesterification reaction of a lower alcohol diester of a dicarboxylic acid, an excess amount of a low molecular weight glycol and a low melting point polymer segment component in the presence of a catalyst, or an excess amount with a dicarboxylic acid. A method of polycondensing the reaction product obtained by esterifying the glycol and low melting point polymer segment components of the catalyst in the presence of a catalyst, or by making a high melting point crystalline segment in advance and adding a low melting point segment component to this randomly by transesterification reaction. Any method, such as a method of forming a high melting point crystalline segment and a method of connecting the low melting point polymer segment with a chain linking agent, may be taken.

In the present invention, a thermoplastic elastomer (B) in which a styrenic elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin is used. The thermoplastic elastomer (B) is obtained by dynamically crosslinking a part of a styrenic elastomer. The thermoplastic elastomer (B) has a structure in which, for example, a thermoplastic elastomer of a styrenic elastomer having a crosslinked structure is dispersed in a matrix resin made of a thermoplastic elastomer of a styrenic elastomer. When the thermoplastic elastomer (B) disperses the thermoplastic elastomer of a styrenic elastomer having a crosslinked structure in a matrix resin composed of a thermoplastic elastomer of a styrenic elastomer, the thermoplastic matrix and the dispersed phase are glycidyl group, carboxyl group, acid anhydride group, and hydroxyl group. , It is preferable to graft-modify it with a functional group monomer having an amino group or a derivative thereof. Further, the thermoplastic elastomer (B) may contain a rubber softener such as paraffinic oil, or a filler such as magnesium carbonate or talc.

The thermoplastic elastomer (B) is preferably a dynamic crosslinking of a part of a thermoplastic elastomer composed of a styrenic elastomer, and a thermoplastic elastomer composed of a styrenic elastomer having a crosslinked structure is dispersed in a thermoplastic matrix composed of a thermoplastic elastomer of a styrenic elastomer. Is to have.

The thermoplastic elastomer (B) in which a styrenic elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin is, for example, a brand name "ACTYMER" manufactured by Rikentechnos ("ACTYMER") LQA7998U.

The thermoplastic elastomer (B) obtained by dispersing a styrenic elastomer having a crosslinked structure as a dispersed phase in a matrix resin may be of a single composition or may be used in combination of two or more of different compositions.

The thermoplastic elastomer resin composition of the present invention contains 10 to 50% by weight of a graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer to a rubber polymer.

As the rubbery polymer used in the graft copolymer (C) used in the present invention, an acrylic rubber containing a polyalkyl (meth)acrylate rubber is exemplified. Emulsion polymerization is the most suitable method for producing a rubbery polymer.

The vinyl monomer used in the graft polymerization is preferably at least one selected from aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters, and vinyl cyanide compounds.

The graft copolymer (C) obtained by graft polymerization of a vinyl monomer to a rubber polymer is preferably obtained using an acrylic rubber containing a polyalkyl (meth)acrylate rubber.

It is preferable that the glass transition temperature obtained from the peak temperature of the measured loss tangent (tanδ) when measuring the graft copolymer (C) used in the present invention with a dynamic viscoelastic analyzer is -20°C or less. When the glass transition temperature is higher than -20°C, flexibility at low temperature is lost, which is not preferable.

The graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer to a rubber polymer may have a single composition or may be used in combination of two or more of different compositions.

In the present invention, a thermoplastic elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin by dynamically crosslinking a thermoplastic elastomer composed of a styrene-based elastomer with respect to 20 to 80% by weight of the polyether ester block copolymer (A) (B ) Is 10 to 50% by weight, and 10 to 50% by weight of a graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer to a rubber polymer is used. In the present invention, a polyether ester block copolymer (A), a thermoplastic elastomer in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin (B), and a graft obtained by graft polymerization of a vinyl-based monomer to a rubbery polymer The total amount of the copolymer (C) is 100% by weight.

When the blending amount of the polyether ester block copolymer (A) is less than 20% by weight, the chemical resistance of the resin composition, fluidity at the time of molding, and appearance of the molded article are poor and become insufficient. When it exceeds 80% by weight, flexibility becomes insufficient.

The blending amount of the polyether ester block copolymer (A) is preferably 20 to 75% by weight, more preferably 20 to 70% by weight.

When the blending amount of the dynamically crosslinked thermoplastic elastomer (B) in which a styrenic elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin is less than 10% by weight, flexibility is insufficient, and when it exceeds 50% by weight, it occurs during molding. Due to the large amount of gas, the fluidity decreases and the appearance of the molded product is poor.

The blending amount of the thermoplastic elastomer (B) obtained by dispersing a styrenic elastomer having a crosslinked structure as a dispersed phase in a matrix resin is preferably 15 to 45% by weight, more preferably 15 to 40% by weight.

When the blending amount of the graft copolymer (C) obtained by graft polymerization of a vinyl monomer on a rubber polymer is less than 10% by weight, flexibility is insufficient, and when it exceeds 50% by weight, gas generated during molding In many cases, the fluidity decreases, and the appearance of the molded article deteriorates.

The blending amount of the graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer to a rubber polymer is preferably 15 to 45% by weight, more preferably 15 to 40% by weight.

The thermoplastic elastomer resin composition of the present invention is preferably a polyether ester block copolymer (A), a thermoplastic elastomer in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin (B), and a vinyl-based monomer is grafted on a rubber polymer. It contains 5 to 25 parts by weight, more preferably 5 to 20 parts by weight, of a styrene-based elastomer (D) having no crosslinked structure, based on 100 parts by weight of the total amount of the graft copolymer (C) obtained by polymerization.

The styrene-based elastomer (D) that does not have a crosslinked structure used in the present invention is preferably a hydrogenated styrene obtained by hydrogenating a random copolymer or a block copolymer composed of a conjugated diene monomer unit and a vinyl aromatic monomer unit. It is a copolymer. As the styrene elastomer (D) having no crosslinked structure, a random copolymer or block copolymer of styrene-butadiene and styrene-isoprene is exemplified. The method for producing the styrenic elastomer (D) not having a crosslinked structure is not particularly limited.

As the styrene-based elastomer (D) having no crosslinked structure, one having a single composition may be used, or two or more kinds of one having different compositions may be used in combination.

If the blending amount of the styrenic elastomer (D) having no crosslinked structure is 25 parts by weight or less, since the mold release from the mold is excellent, it is preferable.

In the present invention, the thermoplastic elastomer resin composition preferably has a melt viscosity index (MFR) of 5 g/10 min or less as measured by a load of 2160 g after heating at a temperature of 220° C. for 5 minutes according to the method described in ASTM D-1238. The melt viscosity index (MFR) measured with a load of 2160 g after heating at a temperature of 220° C. for 5 minutes according to the method described in ASTM D-1238 is more preferably 4 g/10 minutes or less. According to the method described in ASTM D-1238, if the melt viscosity index (MFR) measured with a load of 2160 g after heating at a temperature of 220° C. for 5 minutes is 5 g/10 minutes or less, it is difficult to generate burrs in the molded article.

In the present invention, the thermoplastic elastomer resin composition preferably has a melt viscosity index (MFR) of 10 g/10 min or more, measured by a load of 5000 g after heating at a temperature of 220° C. for 5 minutes. After heating at a temperature of 220° C. for 5 minutes, the melt viscosity index (MFR) measured with a load of 5000 g is more preferably 12 g/10 minutes or more. If the melt viscosity index (MFR) measured with a load of 5000 g after heating at 220° C. for 5 minutes is 10 g/10 minutes or more, it is preferable because of high fluidity.

Antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, lubricants, dyes, pigments, etc. may be added to the thermoplastic elastomer resin composition of the present invention as necessary within a range that does not impair the purpose.

The thermoplastic elastomer resin composition of the present invention can be formed into a molded article preferably by injection molding. The molded article obtained from the thermoplastic elastomer resin composition of the present invention is more preferably a composite molded article.

The method for producing the thermoplastic elastomer resin composition of the present invention includes, for example, a polyether ester block copolymer (A), a thermoplastic elastomer (B) in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin, and a copolymer rubbery polymer. The graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer and a styrene-based elastomer (D) having no crosslinked structure are mixed together into a screw-type extruder and melt-kneaded. First, a polyether ester block copolymer is supplied, and a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin by dynamically crosslinking a thermoplastic elastomer composed of a styrene-based elastomer from another supply port. A method of supplying and kneading can be appropriately adopted.

In particular, it is preferable to perform vacuum degassing treatment from a vent-port of the cylinder part of the extruder during melt-kneading, and degassing the resin composition at a temperature of 80°C to 140°C at which substantially no solid phase polymerization occurs. .

[ Example ]

Hereinafter, the effects of the present invention will be described according to examples. In addition,% in Examples is all based on weight when not specified. In addition, the physical properties shown in the examples were measured as follows.

[Surface hardness (durometer A)]

It measured at 23 degreeC according to JIS K7215-2007.

[Melt Viscosity Index (MFR)]

According to ASTM D-1238-1990, it was measured under conditions of a load of 2160 g after heating at a temperature of 220° C. for 5 minutes and a load of 5000 g after heating at a temperature of 220° C. for 5 minutes.

[Mechanical properties]

According to JIS K7113-1997, the tensile strength at break, the elongation at break at 23°C, and the tensile modulus at 23°C and -20°C were measured.

[Heat fusion adhesion]

First, using a mixed resin pellet ("Iupilon" ("Iupilon") MB2115R manufactured by Mitsubishi Engineering Co., Ltd.) dried at 120° C. for 3 hours, a width of 20 mm and a length of 60 mm , An L-shape with a thickness of 1 mm was produced by injection molding under conditions of a cylinder temperature of 260°C and a mold temperature of 50°C. The molded L-shaped molded article (B) was set in a mold having the shape shown in FIG. 2. After that, the thermoplastic elastomer resin composition pellets dried at 80°C for 3 hours are injection-molded at a cylinder temperature of 220°C, a mold temperature of 50°C, an injection speed of 30㎜/sec, and a holding pressure of a minimum holding pressure of +2 MPa required for filling. A molded article (A) made of the composition and a composite molded article in which the molded article (B) are bonded were obtained. This was allowed to stand at 23°C and 50% RH for 1 day, and then subjected to a tensile test under the conditions of a strain rate of 50 mm/min by the method shown in FIG. 3, and the maximum tension obtained was measured as the heat-sealing adhesive force. In addition, the state of the peeled adhesive interface after measuring the thermal fusion adhesion was classified into two steps below.

A: A state in which the thermoplastic elastomer resin composition is broken without being peeled off from the heat-sealed adhesive surface,

B: A state in which a part of the thermoplastic elastomer resin composition remains on the peeled hard resin adhesive surface after being peeled off from the heat-sealed adhesive surface.

[Burr generation amount]

The thermoplastic elastomer resin composition pellets dried at 80° C. for 3 hours were injection-molded using an injection molding machine having a maximum clamping pressure of 80 tons. It was a cylinder temperature of 220°C when injection-molded, a mold temperature of 50°C, an injection speed of 30 mm/sec, and a holding pressure of a minimum holding pressure of +10 MPa required for full filling. In the injection molding, a plate having a thickness of 2 mm at a length of 30 mm from the gate side and a thickness of 1 mm at a length of 30 mm to 60 mm from the gate side of 30 mm in length and 60 mm in width shown in FIG. It was injection-molded from the formed 0.8 mm phi gate. The length of the burr generated on the parting surface of the 27 mm part in the length direction from the gate side of this plate was read as the amount of burr generation, and measured with a microscope.

[Appearance of molded product]

The thermoplastic elastomer resin composition pellets dried at 80°C for 3 hours were injection-molded under conditions of a cylinder temperature of 220°C, a mold temperature of 50°C, and an injection speed of 30 mm/sec. The surface condition of the obtained plate-shaped molded article having a length of 125 mm, a width of 75 mm, and a thickness of 2 mm was visually confirmed, and evaluated in the following three steps.

○: The surface appearance of the molded product is good

×-1: Poor appearance due to flow mark phenomenon occurring on the entire surface of the molded product

×-2: The appearance is poor due to the occurrence of embossing of rubbery substances on the entire surface of the molded product.

[Peeling]

The state of peeling in the vicinity of the gate of the plate-shaped molded article used in the measurement of the amount of burr generation was visually confirmed, and the following evaluation was performed in two steps.

○: No peeling

×: there is peeling

[Mold contamination]

The thermoplastic elastomer resin composition pellet dried at 80° C. for 3 hours was used in the measurement of the amount of burr generation, and 30 shots were continuously injection-molded under the same molding machine and the same molding conditions as the measurement of the amount of burr generated. The surface of the mold after that was visually checked and evaluated in the following three steps.

○: No contamination on the entire surface of the mold

△: There is contamination on a part of the mold surface

×: There is contamination on the entire surface of the mold

[Reference example]

[Polyether ester block copolymer (A-1)]

273 parts of dimethyl terephthalate acid, 120 parts of 1,4-butanediol, and 723 parts of poly(tetramethylene oxide) glycol having a number average molecular weight of about 2,000 are used together with 3 parts of titanium tetrabutoxide and 3 parts of trimellitic anhydride, together with a helical ribbon (Helical ribbon) type stirring blades were added to the reaction vessel. It heated at 210 degreeC for 2 hours and 30 minutes, and methanol of 95% of the theoretical amount of methanol was flowed out of the system. 0.5 parts of "Irganox" ("Irganox") 1330 (a hindered phenol-based antioxidant manufactured by Chiba Geiggi) was added to the reaction mixture, and then the temperature was raised to 245°C, and the pressure in the system was reduced to 27 Pa over 50 minutes. , Polymerization was performed for 1 hour and 50 minutes under the conditions. The obtained polymer was discharged into water in a strand shape, and cut into pellets.

The thus obtained polyether ester block copolymer (A-1) had a melt viscosity index (MFR) of 5 g/10 min and a durometer A of 77 A measured at a temperature of 190°C and a load of 2160 g.

[Polyether ester 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 1,400 were put together with 0.2 parts of titanium tetrabutoxide into a reaction vessel equipped with a helical ribbon-type stirring blade. It was heated at 190 to 225°C for 3 hours to perform esterification reaction while flowing the reaction water out of the system. 0.5 parts of "Irganox" ("Irganox") 1098 (a hindered phenol-based antioxidant manufactured by Chiba Geiggi) was added to the reaction mixture, and then the temperature was raised to 245°C, and the pressure in the system was reduced to 27 Pa over 50 minutes. , Polymerization was performed for 2 hours and 45 minutes under the conditions. The obtained polymer was discharged into water in a strand shape, and cut to obtain pellets.

The thus obtained polyether ester block copolymer (A-2) had a melt viscosity index (MFR) of 12 g/10 min and a durometer A of 90 A measured at a temperature of 200°C and a load of 2160 g.

[Thermoplastic elastomer (B)]

"ACTYMER" ("ACTYMER") LQA7998U manufactured by Riken Technos Co., Ltd.

[Graft Copolymer (C)]

Mitsubishi Rayon Co., Ltd. "METABLEN" W-450A (glass transition temperature -30℃)

[Styrene-based thermoplastic elastomer (D)]

Asahi Kasei Chemicals Co., Ltd. "S.O.E" L606(D-1)

Asahi Kasei Chemicals Co., Ltd. "Tuftec" ("TUFTEC") H1272(D-2)

[Core-shell copolymer (F) using butyl acrylate as a core polymer and styrene and acrylonitrile as a shell polymer]

OMNOVA Solutions, Inc. "Sunny Gum" ("SUNIGUM") P95 (glass transition temperature 3°C)

[Examples 1 to 7]

Polyether ester block copolymers (A-1) obtained in Reference Examples (A-1), thermoplastic elastomers (B) to (A-2), graft copolymers (C) obtained by graft polymerization of vinyl monomers to rubbery polymers, crosslinked structure The styrenic elastomers (D-1) and (D-2) which do not have a were dry blended at the compounding ratios shown in Table 1, respectively. The dry-blended compound was melt-kneaded at 200°C, using a twin screw extruder having a cylinder diameter of 26 mmφ and subjected to vacuum degassing from a vent port at a location close to the cylinder discharge port, and then pelletized. The obtained pellet was put into a shelf-type hot air dryer, and dried at 80° C. for 3 hours to obtain a thermoplastic elastomer composition. Table 2 shows the evaluation results.

[Comparative Example 1-Comparative Example 4]

Each component was dry blended in the blending ratio shown in Table 1, and pelletized in the same manner as in Examples 1 to 7. Table 3 shows the evaluation results in the same manner as in Examples 1 to 7.

[Comparative Example 5, Comparative Example 6]

Dry blend with the blending ratio shown in Table 2 using "Sunny Gum" ("SUNIGUM") P95 (a graft copolymer obtained by graft polymerization of a vinyl monomer to a rubbery polymer) manufactured by OMNOVA Solutions as a flexible material. ) And pelletized in the same manner as in Examples 1 to 7. Table 3 shows the evaluation results in the same manner as in Examples 1 to 7.

From the above results, Examples 1 to 7 in which the thermoplastic elastomer resin composition of the present invention was obtained are flexible, maintain flexibility at low temperatures, have few burrs on the molded article, have good surface appearance of the molded article, and have good peelability. There was no contamination of the mold, and it was a material having high heat fusion adhesion to hard resins.

On the other hand, the resin composition of Comparative Example 1 has many burrs of a molded article. The resin composition of Comparative Example 2 has a poor surface appearance and contamination of the mold because the rubbery substance is embossed on the surface of the molded article. The resin composition of Comparative Example 3 has a large number of burrs in the molded article, and the surface appearance is poor because the rubbery substance is embossed on the surface of the molded article. The resin composition of Comparative Example 4 has a poor surface appearance because flow marks are generated on the surface of the molded article. The resin composition of Comparative Example 5 does not have flexibility at low temperatures, and the surface appearance is bad because there is embossing of a rubbery substance on the surface of the molded article, and there is contamination on a part of the mold surface. In the resin composition of Comparative Example 6, peeling occurs.

(A) A molded article made of a thermoplastic elastomer resin composition for composite molding
(B) A molded product made of a mixed resin of a polycarbonate resin and an ABS resin

Claims (10)

20 to 80% by weight of a polyether ester block copolymer (A) comprising a high melting point crystalline polymer segment (a1) composed of crystalline aromatic polyester and a low melting point polymer segment (a2) composed of aliphatic polyether units as constituent components, 10 to 50% by weight of a thermoplastic elastomer (B) in which a styrene-based elastomer having a crosslinked structure is dispersed as a dispersed phase in a matrix resin, and 10 to 50% by weight of a graft copolymer (C) obtained by graft polymerization of a vinyl-based monomer in a rubber polymer. Including,
A styrenic thermoplastic elastomer having no crosslinked structure (D), a polyether ester block copolymer (A), a thermoplastic elastomer having a crosslinked structure dispersed as a dispersed phase in a matrix resin (B), and a vinyl-based rubber polymer A thermoplastic elastomer resin composition comprising 5 to 25 parts by weight per 100 parts by weight of the total amount of the graft copolymer (C) obtained by graft polymerization of a monomer. The method of claim 1,
A thermoplastic elastomer resin, characterized in that the high melting point crystalline polymer segment (a1) of the polyether ester block copolymer (A) consists of a polybutylene terephthalate unit or a polybutylene terephthalate unit and a polybutylene isophthalate unit. Composition. The method of claim 1,
The low melting point polymer segment (a2) of the polyether ester block copolymer (A) is a poly(tetramethylene oxide) glycol, an ethylene oxide adduct of poly(propylene oxide) glycol, and an ethylene oxide and tetrahydrofuran. Thermoplastic elastomer resin composition, characterized in that at least one selected from copolymer glycol. The method of claim 1,
The thermoplastic elastomer (B) is a dynamic crosslinking of a part of a thermoplastic elastomer made of a styrenic elastomer, and has a structure in which a thermoplastic elastomer made of a styrenic elastomer having a crosslinked structure is dispersed in a thermoplastic matrix made of a thermoplastic elastomer of a styrenic elastomer. Thermoplastic elastomer resin composition, characterized in that. The method of claim 1,
A thermoplastic elastomer resin composition, characterized in that the graft copolymer (C) obtained by graft polymerization of a vinyl monomer to a rubber polymer is obtained using an acrylic rubber containing a polyalkyl (meth)acrylate rubber. delete The method of claim 1,
The thermoplastic elastomer resin composition characterized in that the styrene-based thermoplastic elastomer (D) having no crosslinked structure is a hydrogenated styrene copolymer obtained by hydrogenating a random copolymer or a block copolymer composed of a conjugated diene monomer unit and a vinyl aromatic monomer unit. The method according to any one of claims 1 to 5,
The glass transition temperature obtained from the peak temperature of the loss tangent (tanδ) measured when the graft copolymer (C) obtained by graft polymerization of a vinyl monomer to a rubber polymer was measured with a dynamic viscoelastic analyzer was -20°C or less. Thermoplastic elastomer resin composition, characterized in that. A molded article obtained by injection molding the thermoplastic elastomer resin composition according to any one of claims 1 to 5. The method of claim 9,
A molded article, characterized in that it is a composite molded article.

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