JP2005325220A - Thermoplastic elastomer resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer resin composition which is flexible and has high impact resilience, toughness, excellent scratch resistance and impact resistance, and has a small compression set.
A polyether mainly composed of a high-melting-point crystalline polymer segment (a) mainly composed of a crystalline aromatic polyester unit and a low-melting-point polymer segment (b) mainly composed of an aliphatic polyether unit. Polyisocyanate compound (C) 0.05 to 10% by weight with respect to 100 parts by weight of the total amount of ester block copolymer (A) 5 to 95% by weight and thermoplastic polyurethane elastomer (B) 95 to 5% by weight. A thermoplastic elastomer resin composition characterized in that the specific wear amount satisfies a specific formula.
[Selection figure] None

Description

  The present invention relates to a thermoplastic elastomer resin composition that is flexible and has high impact resilience, is tough, has excellent scratch resistance and impact resistance, and has a low compression set.

  Polyether ester block copolymers with crystalline aromatic polyester units such as polybutylene terephthalate units as hard segments and aliphatic polyether units such as poly (alkylene oxide) glycol as soft segments are flexible and rebounding Excellent mechanical properties such as strength, impact resistance, and elastic recovery, low temperature and high temperature characteristics, and thermoplastic molding that is easy to process. Applications are expanding to fields such as film.

  Thus, it is a polyether ester block copolymer with excellent physical properties, but if it uses a flexible and high impact resilience polyether block block copolymer, it will be scratch resistant and impact resistant under harsh conditions Since there is a shortage, it is easy to be scratched when rubbed, easily broken when pulled at high speed, and easily broken when given large mechanical energy. In addition, the flexible polyether ester block copolymer has a problem that the compression set is large. For this reason, when it is applied to applications where a flexible polyetherester block copolymer is rubbed with a hard one, stretched instantaneously at a high speed, or receives a large amount of mechanical energy, it can withstand practical use. Sometimes it was not possible.

  Thus, when scratch resistance and impact resistance under severe conditions are required, it has been generally performed to use a polyether ester block copolymer having higher hardness. However, if a polyether ester block copolymer having a high hardness is used, not only the feeling is deteriorated, but also the resilience is lowered and the rubbery property is retreated, so that the flexibility of the polyether ester block copolymer is reduced. In addition, while maintaining the features of high rebound resilience, the emergence of a material that is tough, excellent in scratch resistance and impact resistance, and has a low compression set has been awaited.

  On the other hand, a thermoplastic polyurethane elastomer is a material that is flexible and excellent in wear resistance, but has a problem that its resilience is low and its rubber elasticity is insufficient. Also in thermoplastic polyurethane elastomers, a problem common to thermoplastic elastomers is the insufficient performance in terms of large compression set.

A resin composition (for example, see Patent Document 1) in which a polyether ester block copolymer is blended with a thermoplastic polyurethane elastomer is known for the purpose of improving molding processability, heat resistance, and hydrolysis resistance. . Further, a block copolymer thermoplastic polyurethane elastomer obtained by reacting a polyether ester block copolymer with a polyisocyanate compound for the purpose of improving moldability and heat resistance is known (for example, see Patent Documents 2 and 3). In addition, a composition in which a specific diisocyanate compound is blended with a polyester block copolymer for the purpose of improving bending fatigue resistance and fish eye during molding is also known (for example, see Patent Document 4). Furthermore, a resin composition excellent in abrasion resistance obtained by blending a polyisocyanate compound and a silicone compound in a polyether ester block copolymer (see, for example, Patent Documents 5 and 6) is also known. However, none of these resin compositions sufficiently satisfy the required performance of being flexible and having high impact resilience, being strong, excellent in scratch resistance and impact resistance, and having a low compression set.
Japanese Patent Publication No.52-786 JP 52-121699 A JP-A-57-78413 JP-A-61-111318 JP-A-9-136934 Japanese Patent Laid-Open No. 10-101761

  The present invention has been made as a result of examining the solution of the problems in the above-described prior art as an object. Accordingly, an object of the present invention is to provide a thermoplastic elastomer resin composition that is flexible and has high impact resilience, is tough, has excellent scratch resistance and impact resistance, and has a low compression set.

  To achieve the above object, according to the present invention, a high-melting-point crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low-melting-point polymer segment mainly composed of aliphatic polyether units ( Polyester ester block copolymer (A) 5 to 95% by weight with b) as a main component and thermoplastic polyurethane elastomer (B) 95 to 5% by weight in a total amount of 100 parts by weight, A thermoplastic elastomer resin composition containing 0.05 to 10 parts by weight of an isocyanate compound (B), which is described in JIS K7218 on a molded product applicable to method A described in JIS K7218. In sliding wear when a hollow cylindrical metal is rotated by applying a load according to method A, the test speed v is 0.5 m / s and the test load P is 5 A thermoplastic elastomer resin composition is provided in which the specific wear amount satisfying the following formula (1) when 0 N and the sliding distance L are set to 3 km is provided.

Vx = {(Wa−Wb) / (ρ · 1000)} / (P · L) ≦ 0.5
... (1)
(Where Vx is the specific wear amount (mm ³ / (N · km)) of the thermoplastic elastomer resin composition, and Wa and Wb are test pieces before the test of the test piece which is a molded article made of the thermoplastic elastomer resin composition, respectively. (The latter mass (mg), Wa-Wb is the wear amount (mg), and ρ is defined as the density (kg / m ³ ) of the thermoplastic elastomer resin composition.)

In the thermoplastic elastomer resin composition of the present invention,
The polyisocyanate compound (C) is a polyisocyanate compound in which the number of isocyanate groups contained in one molecule exceeds 2 on average,
50% or more of the polyisocyanate compound (C) is an isocyanate compound having 3 or more isocyanate groups in one molecule;
70% or more of the polyisocyanate compound (C) is an isocyanate compound having 3 or more isocyanate groups in one molecule;
However, both are preferable conditions, and by applying these conditions, it can be expected to obtain a more excellent effect.

  According to the present invention, as described below, a thermoplastic elastomer resin composition that is flexible and has high impact resilience, is strong, has excellent scratch resistance and impact resistance, and has a low compression set can be obtained.

  Hereinafter, the present invention will be described in detail.

  The polyether ester block copolymer (A), which is one of the components used in the present invention, comprises a high-melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and mainly aliphatic polyether units. The low-melting polymer segment (b) consisting of The high-melting crystalline polymer segment (a) is a unit comprising a crystalline aromatic polyester formed from an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol, preferably terephthalic acid and / or dimethyl terephthalate. Is a polybutylene terephthalate unit derived from 1,4-butanediol, but in addition to this, terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, A dicarboxylic acid component such as diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, or an ester-forming derivative thereof, and a diol having a molecular weight of 300 or less, such as 1,4-butanediol, Ethylene glycol, trimethylene glycol Aliphatic diols such as pentamethylene glycol, hexamethylene glycol, neopentyl glycol and decamethylene glycol, alicyclic diols such as 1,4-cyclohexanedimethanol and tricyclodecane dimethylol, 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] cyclohexane, 4,4'-dihydroxy-p-terphenyl, polyester units derived from aromatic diols such as 4,4'-dihydroxy-p-quarterphenyl, or the like Dicarboxylic acid component and The diol component may be a combination copolyester units of two or more. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, polyfunctional oxyacid component, polyfunctional hydroxy component, and the like in a range of 5 mol% or less.

  The low melting point polymer segment (b) of the polyether ester block copolymer (A) used in the present invention is a unit comprising an aliphatic polyether as a main constituent component. Specific examples of the aliphatic polyether 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, poly ( And propylene oxide) glycol ethylene oxide addition polymers and copolymers of ethylene oxide and tetrahydrofuran. Among these aliphatic polyethers, use of poly (tetramethylene oxide) glycol and poly (propylene oxide) glycol ethylene oxide adducts is preferred because the resulting polyester block copolymer has excellent elastic properties. 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 (b) in the polyetherester block copolymer (A) used in the present invention is preferably in the range of 10 to 80% by weight, more preferably 15 to 75% by weight. .

  The polyether ester block copolymer (A) used in the present invention is obtained by melt polycondensation. The melt polycondensation can be carried out by a known method. For example, a method in which 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 are transesterified in the presence of a catalyst and the resulting reaction product is polycondensed, an excess amount of the dicarboxylic acid A method in which the glycol and low-melting-point polymer segment components are esterified in the presence of a catalyst and the resulting reaction product is polycondensed, and a high-melting-point crystalline segment is prepared in advance, and a low-melting-point segment component is added thereto Then, any method such as a method of randomizing by transesterification may be used.

  The polyether ester block copolymer (A) obtained by melt polycondensation is then finely divided. Fine granulation may be performed by a cold cut method in which the polyether ester block copolymer (A) taken out in a gut shape or a sheet shape is pelletized with a cutter, or a hot cut method in which pelletization is performed without forming a gut shape or a sheet shape. It may be. Moreover, you may obtain by grind | pulverizing the polyether ester block copolymer (A) taken out to lump shape.

  The thermoplastic polyurethane elastomer (B), which is one of the components used in the present invention, has a polyurethane segment as a hard segment, and an aliphatic polyether, aliphatic polyester, and aliphatic polycarbonate having a molecular weight of about 700 to 8000 as a soft segment. The block copolymer. Aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, and poly (tetramethylene oxide) glycol, and aliphatic polyesters include polyethylene adipate, polybutylene adipate, polybutylene sebacate, and Examples of the aliphatic polycarbonate such as polycaprolactone include polyhexanediol carbonate. Among these soft segments, those using an aliphatic polyether such as poly (tetramethylene oxide) glycol are preferred because the resulting thermoplastic polyurethane elastomer is excellent in elastic properties and low-temperature properties. The thermoplastic polyurethane elastomer (B) of the present invention comprises such a soft segment component and 4,4′-diphenylmethane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, toluene diisocyanate, 1,6-hexamethylene diisocyanate and the like. It is synthesized from diisocyanate compounds and glycols such as ethylene glycol, 1,4-butanediol, and 1,6-hexanediol. Some are completely chain-like and some have some branching and cross-linking.

  As the polyisocyanate compound (C), which is still another component used in the thermoplastic elastomer resin composition of the present invention, a compound having an average number of isocyanate groups in one molecule of 2 or more can be used. Moreover, the polyisocyanate compound in which the number of isocyanate groups contained in one molecule exceeds 2 on average is preferably used, and the polyisocyanate compound having 3 or more isocyanate groups contained in one molecule is more preferably used. Alternatively, a mixture of a polyisocyanate compound having two isocyanate groups contained in one molecule and a polyisocyanate compound having three or more isocyanate groups contained in one molecule can also be preferably used.

  Examples of the diisocyanate compound having two isocyanate groups in one molecule include ethylene diisocyanate, 1,4-tetramethylene diisocyanate, ethyl (2,6-diisocyanate) hexanoate, 1,6-hexamethylene diisocyanate, 1,12- Dodecamethylene diisocyanate, 2,2,4- or 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2- Isocyanatoethyl) carbonate, and aliphatic diisocyanates such as 2-isocyanatoethyl-2,6-diisocyanatohexanoate, 1,3- or 1,4-bis (isocyanatomethylcyclohexane), 1,3- Or , 4-diisocyanatocyclohexane, 3,5,5-trimethyl (3-isocyanatomethyl) cyclohexyl isocyanate, dicyclohexylmethane-4,4′-diisocyanate, 2,5- or 2,6-diisocyanatonorbornane, etc. Aralkylene diisocyanates such as alicyclic isocyanate, m-xylylene diisocyanate, α, α, α ′, α′-tetramethyl-m-xylylene diisocyanate, and m- or p-phenylene diisocyanate, tolylene-2,4- Or 2,6-diisocyanate, diphenylmethane-4,4′-diisocyanate, naphthalene-1,5-diisocyanate, diphenyl-4,4′-diisocyanate, 4,4′-diisocyanato-3,3′-dimethyldiphenyl, 3- Methyl-diph Mention may be made of aromatic diisocyanates such as phenylmethane-4,4'-diisocyanate and diphenyl ether-4,4'-diisocyanate.

  Examples of the polyisocyanate compound having three or more isocyanate groups in one molecule include 1,3,6-hexamethylene triisocyanate, 1,8-diisocyanato-4-isocyanatomethyloctane, 2-isocyanatoethyl (2 , 6-diisocyanate) hexanoate, 2,5- or 2,6-diisocyanatomethyl-2-isocyanatopropylnorbornane, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate, and polymethylene polyphenylene polyisocyanate. Can be mentioned. Furthermore, the polyisocyanate which has the isocyanurate structure obtained by making the isocyanate group of the said diisocyanate or triisocyanate cyclic trimer can be mentioned.

  The polyisocyanate compound (C) used in the present invention is not particularly limited as long as the average number of isocyanate groups contained in one molecule is 2 or more, but preferably 50% or more of the polyisocyanate compound is 1 molecule. An isocyanate compound having 3 or more isocyanate groups is used, and more preferably, 70% or more of the polyisocyanate compound is a polyisocyanate compound having 3 or more isocyanate groups in one molecule.

  In the thermoplastic elastomer resin composition of the present invention, the polyether ester block copolymer (A) is 5 to 95% by weight, preferably 10 to 90% by weight, more preferably 20 to 80% by weight, and thermoplastic polyurethane. The polyisocyanate compound (C) is 0.05 to 10% by weight based on 100 parts by weight of the total amount of the elastomer (B) of 95 to 5% by weight, preferably 90 to 10% by weight, more preferably 80 to 20% by weight. Parts, preferably 0.1 to 5 parts by weight, more preferably 0.2 to 3 parts by weight. When the blending amount of the polyether ester block copolymer (A) is less than 5% by weight, the impact resilience is lowered, and when it is more than 95% by weight, the scratch resistance is lowered. When the blending amount of the polyisocyanate compound (C) is less than the above range, sufficient performance is not imparted, and when the blending amount exceeds the above range, gelation occurs at the time of melt processing, which is not preferable.

  The polyester elastomer resin composition of the present invention comprises the above components (A), (B), and (C) as essential components, and various additives are added within a range that does not impair the object of the present invention. For example, known hindered phenol-based, phosphite-based, thioester-based, aromatic amine-based antioxidants, benzophenone-based, benzotriazole-based, hindered amine-based light-proofing agents, pigments, dyes and other colorants Further, an antistatic agent, a conductive agent, a flame retardant, a reinforcing agent, a filler, a plasticizer, a release agent, and the like can be optionally contained.

  As described above, the polyester elastomer resin composition of the present invention can be obtained by melt-kneading the above components (A), (B) and (C) with various additives as required. The following methods a to g can be employed.

  a. A pellet mixture of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B), or a melt kneaded mixture of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B), A method in which an isocyanate compound (C) is dry blended and injection-molded without prior melt mixing.

  b. Master batch pellets in which a polyisocyanate compound (C) is blended with a thermoplastic resin are mixed with a pellet mixture of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B), or a polyether ester block copolymer. A method of dry blending a melt-kneaded product of (A) and a thermoplastic polyurethane elastomer (B) and injection molding without prior melt mixing. The thermoplastic resin used for the masterbatch pellet is not particularly limited, but preferably has good compatibility with the polyetherester block copolymer.

  c. A pellet mixture of the polyether ester block copolymer (A) and the thermoplastic polyurethane elastomer (B), or a melt kneaded product of the polyether ester block copolymer (A) and the thermoplastic polyurethane elastomer (B). A method in which a raw material blended with an isocyanate compound (C) is supplied to a screw extruder and melt kneaded.

  d. Melt of polyether ester block copolymer (A) and thermoplastic polyurethane elastomer (B) pellet mixture or polyether ester block copolymer (A) and thermoplastic polyurethane elastomer (B) in a screw type extruder A method in which a kneaded product is supplied and melted, and a polyisocyanate compound (C) is further supplied from another supply port, followed by melting and kneading.

  e. Master batch pellets in which a polyisocyanate compound (C) is blended in a thermoplastic resin, a pellet mixture of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B), or a polyether ester block copolymer A method in which raw materials blended in a melt-kneaded product of (A) and a thermoplastic polyurethane elastomer (B) are supplied to a screw-type extruder and melt-kneaded. The thermoplastic resin used for the masterbatch pellet is not particularly limited, but preferably has good compatibility with the polyetherester block copolymer.

  f. Polyether ester block copolymer (A) and thermoplastic polyurethane elastomer (B) pellet mixture, or polyether ester block copolymer (A) and thermoplastic polyurethane elastomer (B) melt-kneaded A method in which a raw material blended with an isocyanate compound (C) is supplied to a kneader such as a roll, kneader, Banbury mixer, etc., melted and kneaded, and then supplied to a screw type extruder to be pelletized.

  g. A pellet mixture of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B), or a melt kneaded product of a polyether ester block copolymer (A) and a thermoplastic polyurethane elastomer (B). A method in which a raw material blended with an isocyanate compound (C) is supplied to a kneading machine such as a roll, kneader, Banbury mixer, etc., taken out after melt kneading, cooled, and then pulverized.

  The thermoplastic elastomer resin composition of the present invention is based on 100 parts by weight of the total amount of the polyether ester block copolymer (A) 5 to 95% by weight and the thermoplastic polyurethane elastomer (B) 95 to 5% by weight. The polyisocyanate compound (C) is blended in an amount of 0.05 to 10 parts by weight. On the molded product applicable to the method A described in JIS K7218, the method A described in JIS K7218 In the sliding wear when rotating the hollow cylindrical metal under a load, when the test speed v is 0.5 m / s, the test load P is 50 N, and the sliding distance L is 3 km, It is necessary that the specific wear amount satisfy the following formula (1), so that it has flexibility and high resilience, is strong, has excellent scratch resistance and impact resistance, and has a low compression set. A plastic elastomer resin composition can be provided. For this reason, the obtained molded article is useful for automobiles, electronic / electrical equipment, precision equipment, and various molded articles for general consumer goods. Furthermore, it is also suitable for packing, gaskets, cushions, shock absorbing structures, hoods, covers, and seats.

Vx = {(Wa−Wb) / (ρ · 1000)} / (P · L) ≦ 0.5
... (1)
(Where Vx is the specific wear amount (mm ³ / (N · km)) of the thermoplastic elastomer resin composition, and Wa and Wb are test pieces before the test of the test piece which is a molded article made of the thermoplastic elastomer resin composition, respectively. (The latter mass (mg), Wa-Wb is the wear amount (mg), and ρ is defined as the density (kg / m ³ ) of the thermoplastic elastomer resin composition.)

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.

  Hereinafter, “%” other than part and rebound resilience are all based on mass. The physical properties of the polyester elastomer resin composition shown in the examples were measured as follows.

[Melting point]
Using a differential scanning calorimeter (DSC-910, manufactured by Du Pont), the top temperature of the melting peak when heated at a heating rate of 10 ° C./min in a nitrogen gas atmosphere was measured.

[Melt viscosity index (MFR value)]
Measured according to ASTM D-1238 at a load of 2160 g.

[surface hardness]
Hardness measured according to ASTM D-2240 (Shore D hardness).

[Rebound resilience]
Measured according to BS standard 903.

[specific gravity]
Measured according to ASTM D-792.

[Amount of wear and specific wear]
A disc having a diameter of 40 mm and a thickness of 3 mm applicable to the method A described in JIS K7218 was formed. Using a wear friction tester (EFM-III-EN / F type manufactured by Orientec Co., Ltd.), load a hollow cylindrical metal on the molded product according to method A described in JIS K7218. And the sliding wear test was conducted. The specific wear amount was determined as the wear resistance under the conditions that the test speed v was 0.5 m / s, the test load P was 50 N, and the sliding distance L was 3 km. This specific wear amount was calculated from the formula Vx = {(Wa−Wb) / (ρ · 1000)} / (P · L). Here, Vx is the specific wear amount (mm ³ / (N · km)) of the polyester elastomer resin composition, and Wa and Wb are before and after the test of the test piece using the molded article made of the polyester elastomer resin composition, respectively. (Wa-Wb) is the amount of wear. ρ is defined as the density (kg / m ³ ) of the polyester elastomer resin composition. Among these, the density ρ (kg / m ³ ) used was a value calculated by specific gravity / 1000.

[Scratch resistance]
A test piece having a length of 140 mm, a width of 50 mm, and a thickness of 2 mm was molded. Using a friction tester type I (clock meter) described in JIS L0849, using Kanaki No. 3 as a white cotton cloth for friction, applying a load of 9 N to the friction element, 10 times between 10 mm between the test pieces 100 mm, The friction element was reciprocated horizontally. The friction surface was observed with the naked eye to confirm the presence or absence of scratches, and was determined as follows.
A: There is no scratch.
○: There is almost no scratch.
Δ: Slightly scratched
×: Clearly scratched.

[High-speed surface impact resistance]
A test piece having a length of 125 mm, a width of 75 mm, and a thickness of 2 mm was molded. Using a servo pulser EHF-U2H-20L, a high-speed surface impact test was conducted at −40 ° C. and a collision speed of 18 m / sec to investigate whether the fracture was a ductile fracture or a brittle fracture.

[Compression set]
A cylindrical molded product having a diameter of 29 mm and a thickness of 10 mm was obtained. The molded product was heat-treated at 70 ° C. for 22 hours in a state compressed by 25%. The compression set was calculated from the ratio between the strain amount and the compression amount. Similarly, it was measured in a heat treatment at 100 ° C. for 70 hours.

[Polyether ester block copolymer (A)]
Polyether ester block polymers (A-1) and (A-2) polymerized and pelletized as shown in Reference Example 1 and Reference Example 2 were used.

[Reference Example 1]
419 parts of terephthalic acid, 409 parts of 1,4-butanediol and 476 parts of poly (tetramethylene oxide) glycol ("Tertan" 1400 manufactured by DuPont) having a number average molecular weight of about 1400 together with 2 parts of titanium tetrabutoxide in a helical ribbon type The reaction vessel equipped with a stirring blade was charged and heated at 190 to 225 ° C. for 3 hours to conduct esterification while distilling the reaction water out of the system.

  After adding 0.75 parts of “Irganox” 1010 (hindered phenol antioxidant manufactured by Ciba Geigy Co.) to this reaction mixture, the temperature was raised to 245 ° C., and then the pressure in the system was increased to 27 Pa over 40 minutes. The polyether ester block copolymer (A-1) was obtained by carrying out polymerization for 2 hours and 40 minutes under the conditions. The obtained polymer was discharged into water as a strand and cut into pellets. The melting point of this pellet was 195 ° C., the melt viscosity index (MFR) measured at 220 ° C. was 18 g / 10 minutes, the hardness was 47 Shore D, and the specific gravity was 1.15.

[Reference Example 2]
Reference Example 1 except that 444 parts of terephthalic acid, 386 parts of 1,4-butanediol and 439 parts of poly (tetramethylene oxide) glycol (PTG1400SN manufactured by Hodogaya Chemical Co., Ltd.) having a number average molecular weight of about 1400 were used. Polymerization and cutting were carried out in the same manner to obtain a polyether ester block copolymer (A-2). The melting point of this pellet was 199 ° C., the melt viscosity index (MFR) measured at 220 ° C. was 16 g / 10 min, the hardness was 50 Shore D, and the specific gravity was 1.17.

[Thermoplastic polyurethane elastomer (B)]
The thermoplastic polyurethane elastomer (B) used in the examples and comparative examples is as follows.

B-1: “Pandex” T-8295 (a polyether type thermoplastic polyurethane elastomer manufactured by DIC Bayer Polymer Ltd., hardness is 56 Shore D)
[Polyisocyanate compound (C)]
The polyisocyanate compound (C) used in Examples and Comparative Examples is as follows.

C-1: “Millionate” MT manufactured by Nippon Polyurethane Industry Co., Ltd.
(Diphenylmethane-4,4′-diisocyanate)
C-2: “Coronate” HX manufactured by Nippon Polyurethane Industry Co., Ltd.
(Polyisocyanate having an isocyanurate structure obtained by trimerizing hexamethylene diisocyanate)
C-3: “Millionate” MR-400 manufactured by Nippon Polyurethane Industry Co., Ltd.
(Polymethylene polyphenyl polyisocyanate, 71% or more of isocyanate having 3 or more isocyanate groups in one molecule)

[Examples 1 to 3]
The pellets of the polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and the pellets of the thermoplastic polyurethane elastomer (B) were mixed with the V-blender at the compounding ratio shown in Table 1. The mixture was dry blended, melt kneaded at 230 ° C. using a twin screw extruder having a diameter of 45 mm and a triple thread type screw, and pelletized to obtain a resin composition. These pellets were dried with hot air at 80 ° C. for 3 hours, and then dry blended together with the polyisocyanate compound (C) using a V-blender so as to have a compounding ratio as shown in Table 1. It was supplied to the hopper of Neomat 150 / 75SYCAP-M type Sumitomo-Nestal injection molding machine manufactured by Kikai Kogyo Co., Ltd. The dry blended mixture was fed into the molding machine from the hopper, melt kneaded in a cylinder set at 240 ° C., and then injection molded into a mold cavity set at 50 ° C. By such a method, a disk-shaped molded product having a diameter of 100 mm and a thickness of 3 mm was obtained. After being allowed to stand at 23 ° C. and 50% RH for 24 hours, the wear amount was measured, and the specific wear amount of the formula (1) was determined from this value. Separately, each test piece was prepared, and the surface hardness and the rebound resilience were measured. Furthermore, scratch resistance, high speed surface impact resistance, and compression set were evaluated. The results are also shown in Table 1.

[Examples 4 to 6]
Each of the polyisocyanate compounds (C-1) to (C-3) was blended in a copolymerized polyester resin, and the contents of the polyisocyanate compounds (C-1) to (C-3) were each 30% by weight. Three types of master batch pellets were prepared. The pellets of the polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and the pellets of the thermoplastic polyurethane elastomer (B) were mixed with the V-blender at the compounding ratio shown in Table 1. The mixture was dry blended, melt kneaded at 230 ° C. using a twin screw extruder having a diameter of 45 mm and a triple thread type screw, and pelletized to obtain a resin composition. These pellets were subjected to hot air drying at 80 ° C. for 3 hours, and then the three types of master batch pellets were converted into a polyetherester block copolymer (A), a thermoplastic polyurethane elastomer (B), and a polyisocyanate compound. Dry blending was performed using a V-blender so that the blending ratio of (C) was as shown in Table 1, and neomat 150 / 75SYCAP-M type Sumitomo-Nestal injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. Supplied to the hopper. The dry blended mixture was fed into the molding machine from the hopper, melt kneaded in a cylinder set at 240 ° C., and then injection molded into a mold cavity set at 50 ° C. By such a method, a disk-shaped molded product having a diameter of 100 mm and a thickness of 3 mm was obtained. After being allowed to stand at 23 ° C. and 50% RH for 24 hours, the wear amount was measured, and the specific wear amount of the formula (1) was determined from this value. Separately, each test piece was prepared, and the surface hardness and the rebound resilience were measured. Furthermore, scratch resistance, high speed surface impact resistance, and compression set were evaluated. The results are also shown in Table 1.

[Examples 7 to 8]
As shown in Table 1, together with the polyisocyanate compound (C), the pellet of the polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and the pellet of the thermoplastic polyurethane elastomer (B) Dry blend using a V-blender at a suitable blending ratio, melt knead at 230 ° C. using a twin screw extruder having a diameter of 45 mm and a triple thread type screw, and pelletize to obtain a thermoplastic elastomer resin composition It was. These pellets were dried with hot air at 80 ° C. for 3 hours, and then supplied to a hopper of a neomat 150 / 75SYCAP-M type Sumitomo-Nestal injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. The dry blended mixture was fed into the molding machine from the hopper, melt kneaded in a cylinder set at 240 ° C., and then injection molded into a mold cavity set at 50 ° C. By such a method, a disk-shaped molded product having a diameter of 100 mm and a thickness of 3 mm was obtained. After being allowed to stand at 23 ° C. and 50% RH for 24 hours, the wear amount was measured, and the specific wear amount of the formula (1) was determined from this value. Separately, each test piece was prepared, and the surface hardness and the rebound resilience were measured. Furthermore, scratch resistance, high speed surface impact resistance, and compression set were evaluated. The results are also shown in Table 1.

[Examples 9 to 10]
Pellets of polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and pellets of thermoplastic polyurethane elastomer (B) were mixed in a kneader having two blades arranged in parallel. The mixture was melted by melting and kneading at 2.5 ° C. for 2.5 minutes, and the polyisocyanate compound (C) was supplied thereto at a blending ratio as shown in Table 1 and further at 240 ° C. Melt kneading for 5 minutes was performed to obtain a thermoplastic elastomer resin composition. The melt-kneaded product was taken out, pulverized with a pulverizer, and press-molded to obtain a press sheet. Using this press sheet, the wear amount, surface hardness, and impact resilience were measured, and the specific wear amount of the formula (1) was determined from the value of the wear amount. The results are also shown in Table 1. Furthermore, scratch resistance, high speed surface impact resistance, and compression set were evaluated. The results are shown in Table 1.

[Comparative Examples 1-6]
The pellets of polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and the pellets of thermoplastic polyurethane elastomer (B) are blended so as to have a blending ratio as shown in Table 2. -Dry blended using a blender, melt kneaded at 230 ° C using a twin screw extruder having a diameter of 45 mm and a triple thread type screw, and then pelletized to obtain a resin composition. These resin composition pellets were subjected to hot air drying at 80 ° C. for 3 hours, and then supplied to a hopper of a neomat 150 / 75SYCAP-M type Sumitomo-Nestal injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. Injection molding was performed in the set mold cavity. By such a method, a disk-shaped molded product having a diameter of 100 mm and a thickness of 3 mm was obtained. After being allowed to stand at 23 ° C. and 50% RH for 24 hours, the wear amount was measured to determine the specific wear amount. Separately, each test piece was prepared to measure surface hardness and impact resilience, and scratch resistance, high-speed surface impact resistance, and compression set were evaluated. The results are shown in Table 2.

[Comparative Example 7]
Pellets of polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and pellets of thermoplastic polyurethane elastomer (B) were mixed in a kneader having two blades arranged in parallel. The mixture was melted by melt kneading at 2.5 ° C. for 2.5 minutes. Here, the polyisocyanate compound (C) was supplied so as to have a blending ratio as shown in Table 2, and when an attempt was made to perform melt kneading at 240 ° C., rapid gelation occurred. The resin composition was wound around the blade. When the resin composition wound around the blade was peeled off from the blade and examined, it was insoluble and infusible, did not have molding processability, and physical properties could not be measured.

[Comparative Example 8]
As shown in Table 2, together with the polyisocyanate compound (C), the pellet of the polyether ester block copolymer (A) subjected to hot air drying at 80 ° C. for 3 hours and the pellet of the thermoplastic polyurethane elastomer (B) The mixture was dry-blended using a V-blender at an appropriate blending ratio, melt-kneaded at 230 ° C. using a twin screw extruder having a diameter of 45 mm and a triple thread screw type, and pelletized to obtain a resin composition. The resin composition pellets were dried with hot air at 80 ° C. for 3 hours, and then supplied to a hopper of a neomat 150 / 75SYCAP-M type Sumitomo-Nestal injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. The dry blended mixture was fed into the molding machine from the hopper, melt kneaded in a cylinder set at 240 ° C., and then injection molded into a mold cavity set at 50 ° C. By such a method, a disk-shaped molded product having a diameter of 100 mm and a thickness of 3 mm was obtained. After being allowed to stand at 23 ° C. and 50% RH for 24 hours, the wear amount was measured, and the specific wear amount of the formula (1) was determined from this value. Separately, each test piece was prepared to measure surface hardness and impact resilience, and scratch resistance, high-speed surface impact resistance, and compression set were evaluated. The results are shown in Table 2.

  From the above results, the thermoplastic elastomer resin compositions of the present invention shown in Examples 1 to 10 have flexibility and high resilience, toughness, excellent scratch resistance and impact resistance, and further compression set. Is small. On the other hand, a composition comprising two components of a polyetherester block copolymer (A) and a thermoplastic polyurethane elastomer (B) without blending the polyisocyanate compound (C) shown in Comparative Examples 1 to 8. In the case of No. 1, it was soft and had a large impact resilience, but it was easily scratched and was not strong and inferior in high-speed surface impact resistance. The compression set was also large.

  The thermoplastic elastomer resin composition of the present invention has the characteristics that it is flexible and has high resilience, is tough, excellent in scratch resistance and impact resistance, and has low compression set. -Useful for various types of molded products for electrical equipment, precision equipment, and general consumer goods.

Claims (4)

Polyether ester block copolymer composed mainly of a high melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low melting polymer segment (b) mainly composed of aliphatic polyether units. The polyisocyanate compound (C) 0.05 to 10 parts by weight is blended with 100 parts by weight of the total amount of the coalescence (A) 5 to 95% by weight and the thermoplastic polyurethane elastomer (B) 95 to 5% by weight. According to method A described in JIS K7218, a hollow cylindrical metal is applied to a molded article that can be applied to method A described in JIS K7218. In sliding wear when rotating, the specific friction when the test speed v is 0.5 m / s, the test load P is 50 N, and the sliding distance L is 3 km. The thermoplastic elastomer resin composition, wherein the amount satisfying the equation (1) below.
Vx = {(Wa−Wb) / (ρ · 1000)} / (P · L) ≦ 0.5
... (1)
(Where, Vx is the specific wear amount of the polyester elastomer resin composition (mm ³ / (N · km)), and Wa and Wb are respectively molded articles made of the thermoplastic elastomer resin composition before and after the test. (Wa-Wb is the wear amount (mg), and ρ is defined as the density (kg / m ³ ) of the thermoplastic elastomer resin composition.) 2. The thermoplastic elastomer resin composition according to claim 1, wherein the polyisocyanate compound (C) is a polyisocyanate compound having an average number of isocyanate groups exceeding 2 in one molecule. 2. The thermoplastic elastomer resin composition according to claim 1, wherein 50% or more of the polyisocyanate compound (C) is an isocyanate compound having 3 or more isocyanate groups in one molecule. 2. The thermoplastic elastomer resin composition according to claim 1, wherein 70% or more of the polyisocyanate compound (C) is an isocyanate compound having 3 or more isocyanate groups in one molecule. 3.