JP5360713B2 - Thermoplastic elastomer resin composition and molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer resin composition which is sufficiently flexible and has resilience, is excellent in moldability and scratch resistance and is also excellent in thermal adhesiveness with other thermoplastic resins such as polyester based resin and styrene based resin, and to provide a molded article comprising the thermoplastic elastomer resin composition. <P>SOLUTION: The thermoplastic elastomer resin composition is made of the total 100 pts.wt. composed of a thermoplastic polyester elastomer (A) having a melting point of 180&deg;C or less, of 60 to 98 pts.wt. and a thermoplastic polyester elastomer (B) having a melting point higher than the melting point of the thermoplastic polyester elastomer (A) by 20 to 55 &deg;C, of 2 to 40 pts.wt. The molded article obtained by molding the thermoplastic elastomer resin composition is also provided. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention provides a thermoplastic elastomer resin composition that is flexible and elastic, excellent in moldability and scratch resistance, and excellent in thermal adhesiveness with other thermoplastic resins such as polyester resins and styrene resins. It relates to a molded body.

  Thermoplastic polyester elastomers have excellent mechanical properties such as strength, impact resistance, elastic recovery, flexibility, and low and high temperature properties, and are thermoplastic and easy to mold. Widely used in fields such as parts and consumer goods. In addition, since it is relatively excellent in heat fusion with other thermoplastic resin compositions, styrene resins such as ABS resin and HIPS resin, polyester resins such as PBT and PC, and two-color molding and ultrasonic It is used as a molded product joined by welding or the like. However, such a thermoplastic polyester elastomer has excellent characteristics, but has a problem of insufficient scratch resistance.

  In order to improve the scratch resistance of thermoplastic polyester elastomers, various studies have been made in the past. For example, a thermoplastic elastomer resin composition comprising a polyisocyanate compound in a thermoplastic polyester elastomer (for example, Patent Document 1). , Patent Document 2), thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, thermoplastic elastomer resin composition comprising a polyisocyanate compound (see, for example, Patent Document 3), thermoplastic polyester elastomer, potassium titanate whisker and substituted amides A thermoplastic polyester elastomer resin composition (for example, see Patent Document 4), and a thermoplastic elastomer resin composition comprising a thermoplastic polyester elastomer and a thermoplastic polyolefin elastomer (for example, Patent Document 5, 6), a thermoplastic elastomer composition in which a liquid olefin polymer and / or a liquid diene copolymer is blended with a thermoplastic polyester elastomer (see, for example, Patent Document 7 and Patent Document 8), a thermoplastic polyester elastomer. A thermoplastic elastomer composition (for example, see Patent Document 9) in which a copolymerized polyether is blended with is proposed.

  However, with these conventional technologies, the thermoplastic elastomer resin composition is hardened to obtain a sufficient scratch resistance effect, and the elastomer characteristic is lost, so that it does not withstand practical use. However, there was a problem that temporary and permanent effects could not be obtained.

JP 2005-290248 A Japanese Patent Laying-Open No. 2005-097458 JP 2005-325220 A JP 2007-146076 A JP 2003-292745 A JP 2003-292744 A JP 2001-106884 A JP 2001-17283 A JP 2001-106885 A

  The object of the present invention is to solve the above-mentioned problems in the prior art, and is flexible and elastic, excellent in moldability and scratch resistance, and heat with other thermoplastic resins such as polyester resins and styrene resins. It is an object of the present invention to provide a thermoplastic elastomer resin composition excellent in adhesiveness and a molded body using the same, particularly a composite molded body.

In order to solve the above-mentioned problems, according to the present invention, the melting point of the thermoplastic polyester elastomer (A) is 60 to 98 parts by weight, and the melting point is 20 to 55 ° C. higher than the melting point of the thermoplastic polyester elastomer (A). Ri Do from the total 100 parts by weight of the thermoplastic polyester elastomer (B) 2 to 40 parts by weight with, was measured at 20 ° C. above the melting point of the thermoplastic polyester elastomer (B), melted at a shear rate of 1216 / sec There is provided a thermoplastic elastomer resin composition having a lower viscosity of the thermoplastic polyester elastomer (B) than the value of the thermoplastic polyester elastomer (A) .

In the thermoplastic elastomer resin composition of the present invention ,
The thermoplastic polyester elastomer (A) mainly comprises a high-melting-point crystalline polymer segment (a1) mainly composed of crystalline aromatic polyester units and a low-melting-point polymer segment (a2) mainly composed of aliphatic polyether units. A polyester block copolymer as a constituent component, wherein the high-melting crystalline polymer segment (a1) is formed from two or more acid components and one or more glycol components. A high-melting-point crystalline polymer segment composed of units, and the thermoplastic polyester elastomer (B) comprises a high-melting-point crystalline polymer segment (b1) composed mainly of crystalline aromatic polyester units, and an aliphatic polymer A low-melting polymer segment (b2) composed of ether units is the main constituent. An ester block copolymer, wherein it copolymerization amount of the low melting polymer segment (b2) is 15 to 55 wt%,
Are mentioned as preferable conditions.

  Further, the molded article of the present invention is characterized by molding the above thermoplastic elastomer resin composition, and in particular, at least a part of the molded article is made of another thermoplastic resin or another thermoplastic resin composition. The best effect is exhibited when the composite molded body is joined to the molded body.

  According to the present invention, a thermoplastic elastomer resin composition that is flexible and rich in elasticity and excellent in molding processability and scratch resistance is obtained, and this thermoplastic elastomer resin composition is utilized for automobiles, electronic It is useful for parts that are touched by human hands in various molded products for use in electrical equipment, precision equipment, and general consumer goods. Especially, it is also suitable for heat fusion with molded products made of other thermoplastic resin compositions. Since it is excellent, it is useful as a composite molded body with a hard thermoplastic resin by a method such as two-color molding, vibration welding, ultrasonic welding, or laser welding.

It is the top view (I) and side view (B) of the L-shaped molded product made from ABS resin shape | molded for thermal adhesive evaluation in the Example. The composite molded body (c) in which the L-shaped molded product (a) in FIG. 1 and the L-shaped molded product (b) made of the evaluation resin composition are joined is evaluated when thermal adhesiveness is evaluated. It is explanatory drawing which shows a tension test direction.

  Hereinafter, the present invention will be described in detail.

  The feature of the present invention is that it is flexible and elastic, excellent in molding processability and scratch resistance, and excellent in thermal adhesiveness with a molded body made of other thermoplastic resin such as polyester resin and styrene resin. In order to achieve the problem of obtaining an elastomer resin composition, a resin composition is formed by blending thermoplastic polyester elastomers having specific different melting points at a specific ratio.

  The thermoplastic polyester elastomer (A) having a melting point of 180 ° C. or lower used in the present invention has a melting point measured by a differential scanning calorimeter (DSC) of 180 ° C. or lower, preferably mainly composed of a crystalline aromatic polyester unit. A polyester block copolymer mainly comprising a high melting point crystalline polymer segment (a1) and a low melting point segment (a2) mainly composed of an aliphatic polyether unit, and the high melting point crystalline polymer segment (a1) ) Is a polyester formed mainly 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-4,4′-dicarboxylic acid. Acid, diphenoxyethane dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, sodium 3-sulfoisophthalate and the like. In the present invention, the aromatic dicarboxylic acid is mainly used. A part of the aromatic dicarboxylic acid is an alicyclic ring such as 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, or 4,4′-dicyclohexyldicarboxylic acid. Or aliphatic dicarboxylic acids such as adipic acid, succinic acid, oxalic acid, sebacic acid, dodecanedioic acid, and dimer acid. Furthermore, ester-forming derivatives of dicarboxylic acids such as lower alkyl esters, aryl esters, carbonates, and acid halides can of course be used equally.

  In the present invention, it is preferable to use two or more of the above acid components, and examples thereof include combinations of terephthalic acid and isophthalic acid, terephthalic acid and dodecanedioic acid, terephthalic acid and dimer acid, and the like. By using two or more acid components, the crystallinity of the high melting crystalline polymer segment can be lowered, flexibility can be added, and thermal adhesiveness with other thermoplastic resins is improved. Is done.

  Next, specific examples of the diol 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, decamethylene glycol and the like. Diols, 1,1-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] Aromatic diols such as hexane, 4,4′-dihydroxy-p-terphenyl, and 4,4′-dihydroxy-p-quarterphenyl are preferred, and such diols may be ester-forming derivatives such as acetylates, alkali metal salts. It can also be used in the form of Two or more of these dicarboxylic acids, derivatives thereof, diol components and derivatives thereof may be used in combination.

  Preferred examples of such high-melting crystalline polymer segment (a1) include polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, isophthalic acid and / or dimethyl isophthalate and 1 Polybutylene isophthalate units derived from 1,4-butanediol, and copolymers of both are preferably used, particularly preferably terephthalic acid and / or dimethyl terephthalate and isophthalic acid and / or dimethyl isophthalate. Those consisting of polybutylene terephthalate / isophthalate units derived from 1,4-butanediol are used.

  The low melting point polymer segment (a2) of the thermoplastic polyester elastomer (A) used in the present invention is an aliphatic polyether.

  Specific examples of such aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (trimethylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, ethylene oxide and Examples include a copolymer of propylene oxide, an ethylene oxide adduct of poly (propylene oxide) glycol, and a copolymer of ethylene oxide and tetrahydrofuran. Of these, poly (tetramethylene oxide) glycol and / or poly (propylene oxide) glycol ethylene oxide adducts and / or copolymers of ethylene oxide and tetrahydrofuran are preferably used.

  The copolymerization amount of the low-melting polymer segment (a2) of the thermoplastic polyester elastomer (A) used in the present invention is usually 45 to 95% by weight, preferably 50 to 90% by weight. ) And (a2), it is important to set the melting point to 180 ° C. or less by setting the copolymerization ratio.

  The thermoplastic polyester elastomer (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.

  The thermoplastic polyester elastomer (B) having a melting point higher by 20 to 55 ° C. than the melting point of the thermoplastic polyester elastomer (A) used in the present invention is the melting point measured by DSC, the thermoplastic polyester elastomer (A). This means that the polymer is 20 to 55 ° C. higher than the melting point of the polymer, and preferably 25 to 50 ° C. higher. When the melting point is not higher than the thermoplastic polyester elastomer (A) by 20 ° C. or more, the moldability improving effect and scratch resistance of the resulting thermal composition elastomer composition are insufficient, and the thermoplastic polyester elastomer (A) When the temperature is higher than 55 ° C., the molten state of the resulting thermoplastic elastomer composition becomes non-uniform, and problems such as deterioration of physical properties and inferior moldability occur.

  The thermoplastic polyester elastomer (B) used in the present invention preferably comprises a high-melting crystalline polymer segment (b1) mainly composed of crystalline aromatic polyester units and a low-melting segment mainly composed of aliphatic polyether units ( b2) as a main constituent component, and the high-melting crystalline polymer segment (b1) is mainly composed of an aromatic dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof. Polyester formed.

  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-4,4′-dicarboxylic acid. Acid, diphenoxyethane dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, sodium 3-sulfoisophthalate and the like. In the present invention, the aromatic dicarboxylic acid is mainly used. A part of the aromatic dicarboxylic acid is an alicyclic ring such as 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, or 4,4′-dicyclohexyldicarboxylic acid. Or aliphatic dicarboxylic acids such as adipic acid, succinic acid, oxalic acid, sebacic acid, dodecanedioic acid, and dimer acid. Furthermore, ester-forming derivatives of dicarboxylic acids such as lower alkyl esters, aryl esters, carbonates, and acid halides can of course be used equally.

  Next, specific examples of the diol 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, decamethylene glycol and the like. Diols, 1,1-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] Aromatic diols such as hexane, 4,4′-dihydroxy-p-terphenyl, and 4,4′-dihydroxy-p-quarterphenyl are preferred, and such diols may be ester-forming derivatives such as acetylates, alkali metal salts. It can also be used in the form of

  Two or more of these dicarboxylic acids, derivatives thereof, diol components and derivatives thereof may be used in combination.

  As a preferred example of such a high-melting crystalline polymer segment (b1), those composed of polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate are preferably used.

  In the low-melting polymer segment (b2) used in the thermoplastic polyester elastomer (B) used in the present invention, an aliphatic polyether can be used as necessary.

  Specific examples of such aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (trimethylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, ethylene oxide and Examples include a copolymer of propylene oxide, an ethylene oxide adduct of poly (propylene oxide) glycol, and a copolymer of ethylene oxide and tetrahydrofuran. Of these, poly (tetramethylene oxide) glycol and / or poly (propylene oxide) glycol ethylene oxide adducts and / or copolymers of ethylene oxide and tetrahydrofuran are preferably used.

  The copolymerization amount of the low-melting point polymer segment (b2) of the thermoplastic polyester elastomer (B) used in the present invention is usually 15 to 55% by weight, preferably 20 to 50% by weight. ) And (b2), it is important to set the melting point of the thermoplastic polyester elastomer (B) to 20 to 55 ° C. higher than the melting point of the thermoplastic polyester elastomer (A). Here, when the copolymerization amount of (b2) is more than 55% by weight, the moldability improving effect and scratch resistance become insufficient, and when (b2) is less than 15% by weight, the thermoplastic elastomer composition obtained is in a molten state. Becomes non-uniform, causing problems such as deterioration of physical properties and inferior moldability.

  The thermoplastic polyester elastomer (B) 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 may be employed, such as a method in which a dicarboxylic acid, an excessive 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, but the melting point is 180 degrees or less. It is necessary to lower the melt viscosity than the thermoplastic polyester elastomer (A), and it is important to lower the molecular weight by controlling the polymerization time.

  Further, it is possible to copolymerize other copolymerizable monomers within a range not impairing the performance of the thermoplastic elastomer resin composition of the present invention. Examples of such other monomers include α, β-unsaturated carboxylic acid esters such as glycidyl acrylate, glycidyl methacrylate, and glycidyl itaconate, and α, β-unsaturated dicarboxylic acids such as maleic anhydride and itaconic anhydride. Examples include anhydrides, imide compounds of α, β-unsaturated carboxylic acids such as N-phenylmaleimide, N-methylmaleimide, and Nt-butylmaleimide.

  In 100 parts by weight of the thermoplastic elastomer resin composition of the present invention, the thermoplastic polyester elastomer (A) having a melting point of 180 ° C. or less is 60 to 98 parts by weight, preferably 65 to 96 parts by weight, and less than 60 parts by weight. Thermal adhesiveness and flexibility with other thermoplastic resins become insufficient, and if it exceeds 98 parts by weight, the moldability and scratch resistance are inferior.

  The blending ratio of (B) having a melting point 20 to 55 ° C. higher than the melting point of the thermoplastic polyester elastomer (A) is 2 to 40 parts by weight, preferably 4 parts in a total of 100 parts by weight of the thermoplastic elastomer resin composition. When the amount is less than 2 parts by weight, the moldability and scratch resistance are inferior, and when it exceeds 40 parts by weight, the flexibility and thermal adhesiveness with other thermoplastic resins become insufficient.

In the present invention, the same temperature of the thermoplastic polyester elastomer (A) having a melting point of 180 ° C. or less and the thermoplastic polyester elastomer (B) having a melting point 20 to 55 ° C. higher than the melting point of the thermoplastic polyester elastomer (A), The relationship of the melt viscosity measured under the same shear rate condition is lower in the thermoplastic polyester elastomer (B) . The measurement conditions for concrete melt viscosity is a condition 20 ° C. higher temperature, shear rate 1216 / sec than the melting point temperature thermoplastic polyester elastomer (B). As described above, since the melt viscosity of the thermoplastic polyester elastomer (B) is lower than the melt viscosity of the thermoplastic polyester elastomer (A), the melt resin is affected by shearing when the thermoplastic polyester elastomer resin composition is injection molded. In addition, the thermoplastic polyester elastomer (B) component is selectively present in a large amount on the surface of the molded product, and further has an effect of improving the crystallinity and is excellent in scratch resistance.

  In the present invention, the mixing method of the thermoplastic polyester elastomer (A) and the thermoplastic polyester elastomer (B) is not limited, and (A) and (B) are mixed at once, and a known method such as a Banbury mixer or an extruder is used. A melt mixing method can be employed.

  Furthermore, in the thermoplastic elastomer resin composition of the present invention, an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, a lubricant, a dye, a pigment, a plasticizer, Additives such as flame retardants and mold release agents, and reinforcing materials such as talc, mica, glass flakes, calcium carbonate, clay, barium sulfate, glass beads, glass fibers, and carbon fibers can be added.

  The thermoplastic elastomer resin composition of the present invention retains the characteristics of a polyester elastomer that is flexible and elastic and excellent in molding processability, so that it can be used as an injection-molded product as it is. Excellent thermal adhesiveness with other thermoplastic resins such as polyester-based resins, so it can be made into composite moldings with these hard resins. These composite moldings are multicolored, including two-color molding. It is manufactured using an injection molding method, an insert molding method, an overmold molding method, or a welding technique such as hot plate welding, vibration welding, ultrasonic welding, or laser welding. These molded bodies and composite molded bodies can be applied to various cases, covers, connectors, grips, rollers, casters and the like.

  The effects of the present invention will be described below with reference to examples. In the examples, “%” and “parts” are based on weight unless otherwise specified. The physical properties shown in the examples are measured by the following measuring methods.

[Melting point measurement]
DSC Q100 manufactured by TA Instruments Inc. was used, and the melting point was measured by heating from room temperature to 240 ° C. at a rate of temperature increase of 10 ° C./min. Further, after maintaining at 240 ° C. for 3 minutes, the solution was cooled to 40 ° C. at a temperature lowering rate of 10 ° C./min, and the crystallization temperature was measured.

[Measurement of melt viscosity]
Capillograph 1C manufactured by Toyo Seiki Seisakusho Co., Ltd. was used, and measurement was performed according to JIS K7199 using a capillary size of φ1 mm × length 10 mm under arbitrary temperature conditions.

[Hardness (Durometer D)]
Measured according to JIS K7215 durometer D hardness.

[Mechanical properties]
According to JIS K7113, the tensile strength at break and the tensile elongation at break were measured.

[Scratch resistance]
Using a friction and wear tester EFM-III-EN / F type manufactured by Orientec Co., Ltd., a disc having a diameter of 40 mm and a thickness of 2 mm from a square plate obtained by injection molding is described on JIS K7218. In accordance with the A method, a sliding wear test was performed by rotating with a load of a hollow cylindrical metal. After conducting the test under the conditions of a test speed of 30 mm / second, a test load of 3 kg, and a sliding distance of 1.8 m, the friction surface of the test piece is observed with the naked eye to confirm the presence or absence of scratches. Slightly scratched, x was clearly determined to be scratched.

[Thermal adhesiveness]
First, an ABS resin (Toyolac 100 manufactured by Toray Industries, Inc.), an L-shaped molded product (a) having a width of 20 mm, a length of 60 mm, and a thickness of 3 mm shown in FIG. Create by injection molding. After the molded L-shaped molded product (a) is set in a mold having the shape shown in FIG. 2, an evaluation resin composition is injection molded under conditions of a cylinder temperature of 220 ° C. and a mold temperature of 50 ° C. Thus, a composite molded body (c) in which the L-shaped molded product (a) and the L-shaped molded product (b) made of the evaluation resin composition were joined was obtained. The composite molded body (c) was allowed to stand at room temperature for 1 day, and then subjected to a tensile test under the condition of a strain rate of 50 mm / min by the method shown in FIG. 2, and the maximum tensile force obtained was measured as an adhesive force.

[Deformation degree at injection mold release]
As a moldability, a JIS No. 2 dumbbell test piece and a square plate having a length of 75 mm × width of 125 mm × thickness of 2 mm were evaluated using a resin composition for evaluation under conditions of a cylinder temperature of 220 ° C., a mold temperature of 50 ° C., and a cooling time of 10 seconds. The degree of deformation of a JIS No. 2 dumbbell specimen that was molded and released from the mold by an ejector was determined as follows.
Deformation degree judgment ○: No deformation ×: Large deformation

[Reference example]
[Production of thermoplastic polyester elastomer (A-1) having a melting point of 180 ° C. or lower]
33.0 parts of terephthalic acid, 10.0 parts of isophthalic acid, 40.3 parts of 1,4-butanediol, and 46.5 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400 were added to 0.04 of titanium tetrabutoxide. 04 parts and 0.02 part of mono-n-butyl-monohydroxytin oxide were charged into a reaction vessel equipped with a helical ribbon type stirring blade and heated at 190 to 220 ° C. for 3 hours to drain the reaction water out of the system. The esterification reaction was carried out. After adding 0.15 part of tetra-n-butyl titanate to the reaction mixture and adding 0.05 part of “Irganox” 1098 (hindered phenol antioxidant manufactured by Ciba Geigy), the temperature was raised to 245 ° C. Then, the pressure in the system was reduced to 27 Pa over 50 minutes, and polymerization was performed for 1 hour and 50 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and pelletized by cutting. The resulting thermoplastic polyester elastomer has a melting point of 162 ° C., a melt viscosity at a shear rate of 1216 / sec measured at a temperature of 218 ° C. is 204 Pa · sec, and a melt viscosity at a shear rate of 1216 / sec measured at 227 ° C. is 181 Pa · sec. The melt viscosity at a shear rate of 1216 / sec measured at 228 ° C. was 180 Pa / sec, and the melt viscosity at a shear rate of 1216 / sec measured at 243 ° C. was 154 Pa · sec.

[Production of Thermoplastic Polyester Elastomer (B-1)]
42.0 parts of terephthalic acid, 40.0 parts of 1,4-butanediol and 47.5 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400, 0.03 part of titanium tetrabutoxide and mono-n-butyl -Both 0.01 parts of monohydroxytin oxides were charged into a reaction vessel equipped with a helical ribbon stirring blade, heated at 200 to 235 ° C for 3 hours, and the esterification reaction was carried out while allowing reaction water to flow out of the system. After adding 0.15 part of tetra-n-butyl titanate to the reaction mixture and adding 0.05 part of “Irganox” 1098 (hindered phenol antioxidant manufactured by Ciba Geigy), the temperature was raised to 245 ° C. Then, the pressure in the system was reduced to 27 Pa over 50 minutes, and polymerization was performed for 1 hour and 50 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and pelletized by cutting. The resulting thermoplastic polyester elastomer had a melting point of 198 ° C. and a melt viscosity of 180 Pa · sec at a shear rate of 1216 / sec measured at a temperature of 218 ° C.

[Production of thermoplastic polyester elastomer (B-2)]
50.5 parts of terephthalic acid, 43.8 parts of 1,4-butanediol and 35.4 parts of poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400, 0.04 part of titanium tetrabutoxide and mono-n-butyl -Both 0.02 parts of monohydroxytin oxide were charged into a reaction vessel equipped with a helical ribbon stirring blade, heated at 190 to 225 ° C for 3 hours, and the esterification reaction was carried out while allowing the reaction water to flow out of the system. 0.2 part of tetra-n-butyl titanate was added to the reaction mixture, and 0.05 part of “Irganox” 1098 (hindered phenol antioxidant manufactured by Ciba Geigy Co.) was added, and the temperature was raised to 245 ° C. Then, the pressure in the system was reduced to 27 Pa over 50 minutes, and polymerization was performed for 1 hour and 50 minutes under the conditions. The obtained polymer was discharged into water in the form of strands and pelletized by cutting. The resulting thermoplastic polyester elastomer had a melting point of 207 ° C. and a melt viscosity of 144 Pa · sec at a shear rate of 1216 / sec measured at a temperature of 227 ° C.

[Production of Thermoplastic Polyester Elastomer (B-3)]
The pellets of thermoplastic polyester elastomer (B-2) were charged into a rotatable reaction vessel, the pressure in the system was reduced to 27 MPa, and solid phase polymerization was performed while rotating at 170 to 180 ° C. for 72 hours. The resulting thermoplastic polyester elastomer had a melting point of 208 ° C. and a melt viscosity of 263 Pa · sec at a shear rate of 1216 / sec measured at a temperature of 228 ° C.

[Production of Thermoplastic Polyester Elastomer (B-4)]
PBT resin Toraycon 1401X31 manufactured by Toray Industries, Inc. was used. The melting point was 223 ° C., and the melt viscosity at a shear rate of 1216 / sec measured at a temperature of 243 ° C. was 122 Pa · sec.

[Examples 1-8] and [Comparative Examples 1-9]
Thermoplastic polyester elastomers (B-1), (B-2) having a melting point 20 to 55 ° C. higher than those of thermoplastic polyester elastomers (A-1) and (A-1) having a melting point of 180 ° C. or less obtained in Reference Examples. (B-4), PBT resin (B-3) is mixed using a V-blender at a blending ratio (% by weight) shown in Table 1, and a twin screw extruder having a diameter of 45 mm and a triple thread type screw Was melt kneaded at 230 ° C. and pelletized.

  The obtained pellets were dried at 80 ° C. for 5 hours, and then the JIS No. 2 dumbbell test piece and the longitudinal length were measured at a mold temperature of 50 ° C. (surface of the mold cavity) using an in-line screw injection molding machine set at 220 ° C. A 120 mm × 70 mm wide × 2 mm thick square plate molded article and a composite molded article for thermal adhesion test with ABS resin were injection molded. Table 1 shows the results of examining the characteristics of each test.

  From the above results, the thermoplastic elastomer resin compositions of the present invention shown in Examples 1 to 8 have the characteristics of a flexible and elastic polyester elastomer, and have excellent scratch resistance and adhesion to ABS resin. In terms of moldability, the crystallization temperature was high, the moldability was improved, and the degree of deformation after release was good. However, Examples 7 and 8 using a high melt viscosity (B-3) are slightly inferior in scratch resistance compared to Examples 4 and 6 using a low melt viscosity (B-2), and tensile fracture Elongation is also reduced.

  The simple substance (A-1) of Comparative Example 1 has a poor degree of deformation after release, which is a measure of scratch resistance and moldability. In addition, the thermoplastic elastomers made of (B-1), (B-2), and (B-3) alone in Comparative Examples 2, 3, and 4 have poor adhesive strength with the ABS resin. Comparative Examples 5 and 7 in which (A-1) is blended with 1 wt% of (B-1) and (B-2) have insufficient effects of improving scratch resistance and formability. ), Comparative Example 6 and Comparative Example 8 containing 50 wt% of (B-2) have insufficient adhesive strength with the ABS resin. In Comparative Example 9 in which (B-4) having a melting point 55 ° C. higher than the melting point of (A-1) was blended, the compatibility with (A-1) was insufficient and the melting point and the crystallization temperature were 2 Therefore, the physical properties are low and a sufficient moldability improving effect cannot be obtained, and the scratch resistance is not good.

  The thermoplastic elastomer resin composition of the present invention can be used as various molded articles for use in automobiles, electronic / electric equipment, precision equipment, and general consumer goods, taking advantage of the above-described excellent characteristics. It is suitable for the use which prevents a damage | wound while obtaining a favorable touch in the part which touches. In addition, since it is excellent in thermal adhesiveness with other thermoplastic resins, it is also suitable as a composite molded body with a hard thermoplastic resin by methods such as two-color molding, vibration welding, ultrasonic welding, and laser welding. .

(A) ... L-shaped molded product made of ABS resin (b) ... L-shaped molded product made of evaluation resin composition (c) ... Composite molded body

Claims (6)

60 to 98 parts by weight of a thermoplastic polyester elastomer (A) having a melting point of 180 ° C. or less, and 2 to 40 parts by weight of a thermoplastic polyester elastomer (B) having a melting point 20 to 55 ° C. higher than the melting point of the thermoplastic polyester elastomer (A). Ri Do from the total 100 parts by weight of the part was measured at 20 ° C. above the melting point of the thermoplastic polyester elastomer (B), the melt viscosity at a shear rate of 1216 / sec, the heat value of the thermoplastic polyester elastomer (a) A thermoplastic elastomer resin composition having a lower value of the thermoplastic polyester elastomer (B) . The thermoplastic polyester elastomer (A) mainly comprises a high-melting-point crystalline polymer segment (a1) mainly composed of crystalline aromatic polyester units and a low-melting-point polymer segment (a2) mainly composed of aliphatic polyether units. A polyester block copolymer as a constituent component, wherein the high-melting crystalline polymer segment (a1) is formed from two or more acid components and one or more glycol components. The thermoplastic elastomer resin composition according to claim 1 , wherein the thermoplastic elastomer resin composition is a high-melting crystalline polymer segment composed of units. The thermoplastic polyester elastomer (B) mainly comprises a high melting point crystalline polymer segment (b1) mainly composed of crystalline aromatic polyester units and a low melting point polymer segment (b2) mainly composed of aliphatic polyether units. The thermoplastic elastomer according to claim 1 or 2 , which is a polyester block copolymer as a constituent component, wherein the copolymerization amount of the low melting point polymer segment (b2) is 15 to 55% by weight. Resin composition. A molded article obtained by molding the thermoplastic elastomer resin composition according to any one of claims 1 to 3 . A molded article obtained by injection molding the thermoplastic elastomer resin composition according to any one of claims 1 to 3. A composite molded body in which at least a part of the molded body according to claim 4 or 5 is joined to a molded body obtained by molding another thermoplastic resin or another thermoplastic resin composition .

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