JP2005240003A - Thermoplastic polyester resin composition and insert-molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester resin composition improved with heat shock resistance and an insert-molded article. <P>SOLUTION: This thermoplastic polyester resin composition contains 100 pts.wt. polyester resin, 0.5-40 pt.wt. acrylic rubber, (C) 0.1-20 pt.wt. epoxy compound and (D) 0.001-1 pt.wt. organic alkaline earth metal salt. The insert-molded article is obtained by insert-molding the resin composition, a metal and an inorganic solid material or a thermosetting resin solid material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thermoplastic polyester resin composition having excellent heat shock resistance and an insert-molded article produced using the same.

  Thermoplastic polyester resins such as polyalkylene terephthalate resins are excellent in mechanical properties, electrical properties, other physical and chemical properties, and have good workability, so they are engineering plastics for automobiles, electrical and electronic parts, etc. Is used in a wide range of applications. However, thermoplastic polyesters have the disadvantage of poor physical shock retention, that is, poor heat shock resistance, when alternately exposed to both high and low temperature atmospheres. In particular, there are uses for inserting a metal or sealing a thermosetting resin such as an epoxy resin or a silicone resin, for example, sealing an automobile electrical ignition coil or a stator core of a small motor. In the case of such parts, due to the difference in expansion / shrinkage ratio due to temperature change between thermoplastic polyester resin and internal metal or thermosetting resin, it is a thin molded product or a molded product with a part with large thickness change. , And a molded product having an acute angle portion, the molded product may break due to a temperature change during use. For this reason, the current situation is that the application and the shape of the molded product are considerably limited.

  Further, in the case of a composition containing a reinforcing filler such as glass fiber, an anisotropy of expansion / contraction rate occurs due to the orientation of the filler in a molded product formed using the composition. In addition, the decrease in elongation due to the blending of the filler further increases the frequency of breakage of the molded product due to temperature changes during use, which is a more serious problem.

Conventionally, in order to improve the high and low temperature impact properties (heat shock properties) of molded products made of metal inserts, the use of polybutylene terephthalate compositions containing polybutylene terephthalate resin as the main component and acrylic rubber has been proposed. (See Patent Document 1). However, due to the progress of thinning of molded products due to the miniaturization of parts and the complexity of the shape due to the modularization of parts, the demand for improving the heat shock resistance of the resins used in these productions has become more severe. It was.
JP-A 63-3055 JP-A-60-219254

  An object of the present invention is to provide a polyester resin composition having further improved heat shock resistance and an insert-molded product having excellent mechanical properties and heat shock resistance.

The present invention has been completed through extensive studies to solve the above problems. The present invention
(A) Polyester resin For 100 parts by weight,
(B) 0.5 to 40 parts by weight of acrylic rubber,
(C) It relates to a polyester resin composition containing 0.1 to 20 parts by weight of an epoxy compound and (D) 0.001 to 1 part by weight of an organic alkaline earth metal salt.

  As one aspect of the present invention, the thermoplastic polyester resin composition further comprising (E) a reinforcing filler in an amount of 1 to 150 parts by weight per 100 parts by weight of the (A) polyester resin; (D) an organic alkaline earth metal The thermoplastic polyester resin composition wherein the salt is calcium stearate or magnesium acetate; (A) the thermoplastic polyester resin composition or any one of the thermoplastic polyester resin compositions wherein the polyester resin is polybutylene terephthalate; An insert-molded article obtained by insert-molding a metal, an inorganic solid, or a thermosetting resin solid is provided.

  In the present invention, by using acrylic rubber, a high heat shock resistance improving effect that cannot be obtained when other elastomers are used is obtained. Furthermore, heat shock resistance is further improved by using an epoxy compound in combination with an organic alkaline earth metal salt that is an epoxy ring-opening catalyst of the epoxy compound. Since the molded article comprising the thermoplastic polyester resin composition of the present invention has excellent characteristics that can withstand long-term heat shock, the concern such as breakage of the molded article is remarkably improved, and a highly reliable product is obtained. As a result, the product value is increased, and therefore, it can be widely used in many fields such as the electric / electronic equipment field, the automobile field, and the machine field.

Hereinafter, the present invention will be described in detail.
In the present invention, the (A) polyester resin is a polyester resin comprising a dicarboxylic acid or a derivative thereof and a diol. The dicarboxylic acid or its derivative is mainly terephthalic acid or its lower alkyl ester, but other acid components include phthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenylether dicarboxylic acid, Aromatic dicarboxylic acids such as 4,4′-benzophenone dicarboxylic acid, 4,4′-diphenoxyethane dicarboxylic acid, 4,4′-diphenylsulfone dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid Acids, cycloaliphatic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc. Aliphatic dicarboxylic acids, their lower alkyl or glyco It may be used in combination one or more of such esters Le.

  The main diols are ethylene glycol and 1,4-butanediol, but other diol components include ethylene glycol, diethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, and polypropylene glycol. Aliphatic diols such as polytetramethylene glycol, dibutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,8-octanediol; 1,2-cyclohexanediol, 1,4 Cycloaliphatic diols such as cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol; or xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4-hydroxy) One or two or more of aromatic diols such as phenyl) propane and bis (4-hydroxyphenyl) sulfone may be used in combination.

  In the present invention, hydroxycarboxylic acids such as lactic acid, glycolic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 6-hydroxy-2-naphthalenecarboxylic acid, p-β-hydroxyethoxybenzoic acid; Monofunctional components such as acid, stearyl alcohol, benzyl alcohol, stearic acid, benzoic acid, t-butylbenzoic acid, benzoylbenzoic acid; or tricarballylic acid, trimellitic acid, trimesic acid, pyromellitic acid, gallic acid, trimethylol Trifunctional or higher polyfunctional components such as ethane, trimethylolpropane, glycerol, pentaerythritol, etc. can be used as the copolymerization component.

  In order to produce a polyester resin comprising the dicarboxylic acid or derivative thereof and a diol, any method is employed. For example, a polybutylene terephthalate composed of a terephthalic acid component and a 1,4-butanediol component will be described. A direct polymerization method in which terephthalic acid and 1,4-butanediol are directly esterified, and dimethyl terephthalate as a main raw material. It is roughly divided into the transesterification method used. The former is different in that water is produced in the initial esterification reaction, and the latter is produced in the initial transesterification reaction. The direct esterification reaction is advantageous from the viewpoint of raw material costs. Polyester production methods are broadly classified into batch methods and continuous methods, depending on the raw material supply or the polymer dispensing form. The initial esterification reaction or transesterification reaction is carried out in a continuous operation, and the subsequent polycondensation is carried out in a batch operation. Conversely, the initial esterification reaction or transesterification reaction is carried out in a batch operation, followed by polycondensation. There is also a method of performing the above by continuous operation.

  The polyester resin used in the present invention is preferably an aromatic polyester resin, and most preferably a polybutylene terephthalate resin having an appropriate mechanical strength. This polybutylene terephthalate resin means that terephthalic acid accounts for 50 mol% or more of the total dicarboxylic acid component, and 1,4-butanediol accounts for 50 wt% or more of the total diol. The terephthalic acid preferably accounts for 80 mol% or more of the total dicarboxylic acid component, and more preferably 95 mol% or more. It is more preferable that 1,4-butanediol occupies 80 mol% or more of the total diol component, and it is even more preferable that 95 mol% or more. The intrinsic viscosity of a polyester resin such as polybutylene terephthalate resin is 0.50 when measured at a temperature of 30 ° C. using a mixed solvent of 1,1,2,2-tetrachloroethane / phenol = 1/1 (weight ratio). It is preferable that it is above, it is preferable that it is 3.0 or less, and it is more preferable that it is 0.5-3.0. If the intrinsic viscosity is less than 0.50, the mechanical properties are not exhibited, and if it is more than 3.0, molding becomes difficult. In addition, you may use together the polyester resin which satisfy | fills the said intrinsic viscosity range of 2 or more types.

  The resin composition of the present invention contains (B) acrylic rubber. Acrylic rubber contributes to the improvement of the heat shock resistance of the resin composition. In the present invention, the use of acrylic rubber provides a significant effect of improving heat resistance, which cannot be obtained when other elastomers are used. (B) Acrylic rubber is a copolymer of acrylic acid ester and methacrylic acid ester. A typical example is graft polymerization of a graft polymerizable monomer such as methyl methacrylate on a polymer obtained by polymerizing an acrylic ester such as butyl acrylate and a small amount of a crosslinkable monomer such as butylene diacrylate. And a rubbery polymer obtained by the above process.

  Preferred examples of the acrylate ester include methyl acrylate, ethyl acrylate, and isobutyl acrylate. Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, -n-butyl methacrylate, and 2-ethylhexyl methacrylate. Examples of the crosslinkable monomer include diacrylic acid-1,4-butylene, diacrylic acid-1,3-butylene, dimethacrylic acid-1,3-butylene, and vinyl acrylate.

  The acrylic ester portion of the acrylic rubber used in the present invention is preferably about 50% by weight or more, preferably about 80% by weight or less, more preferably about 50 to 80% by weight. Modified acrylic rubber may be used, and acrylic rubber modified with silicone has excellent weather resistance and can be used.

  In the composition of the present invention, the blending amount of the acrylic rubber is generally 0.5 parts by weight or more, preferably 1 part by weight or more, more preferably 5 parts by weight with respect to 100 parts by weight of the polyester resin. Part or more, generally 40 parts by weight or less, preferably 30 parts by weight or less, more preferably 20 parts by weight or less. Moreover, it is also preferable that the said compounding quantity is the range which combined these ranges arbitrarily.

  The composition of the present invention further contains (C) an epoxy compound and (D) an organic alkaline earth metal salt. (D) The organic alkaline earth metal salt acts as an epoxy ring-opening catalyst for the (C) epoxy compound, and in the present invention, the composition is obtained by using the components (C) and (D) in combination. It further improves the heat shock resistance of objects.

  The epoxy compound (C) that can be used in the present invention may be any of monofunctional, difunctional, trifunctional and polyfunctional compounds, and a mixture of two or more compounds selected from these compounds. It may be. In particular, a bifunctional, trifunctional or polyfunctional epoxy compound, that is, a compound having two or more epoxy groups in one molecule is preferable. Further, the (C) epoxy compound may be any compound such as a glycidyl compound and an alicyclic epoxy compound obtained from a reaction between an alcohol, a phenolic compound or a carboxylic acid and epichlorohydrin.

  Examples of (C) epoxy compounds include glycidyl ethers such as methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether, allyl glycidyl ether; Diglycidyl ethers such as pentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerin diglycidyl ether, propylene glycol diglycidyl ether, and bisphenol A diglycidyl ether; fatty acid glycidyl esters such as benzoic acid glycidyl ester and sorbic acid glycidyl ester; Acid diglycidyl ester, terephthalic acid diglycidyl ester, orthof Diglycidyl esters such as diglycidyl oxalate; alicyclic diepoxy compounds such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexyl carboxylate; glycidyl imide compounds such as N-glycidyl phthalimide; It is. Among these, a glycidyl ether compound obtained from a reaction between bisphenol A and epichlorohydrin is preferable, and bisphenol A diglycidyl ether is particularly preferable.

  In the composition of the present invention, the amount of the (C) epoxy compound is generally 0.1 parts by weight or more, preferably 0.2 parts by weight or more, more preferably 100 parts by weight of the polyester resin. Is 0.3 parts by weight or more, and generally 20 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight or less. Moreover, it is also preferable that the said compounding quantity is the range which combined these ranges arbitrarily. (C) If the compounding amount of the epoxy compound is less than 0.1 parts by weight, no further improvement effect of heat shock resistance is observed, whereas if it exceeds 20 parts by weight, the composition is caused by crosslinking of the resin during high temperature residence. There is a risk that the fluidity of the composition will decrease.

  The (D) organic alkaline earth metal salt that can be used in the present invention is a salt of an alkaline earth metal of Ca, Mg, and Ba and an organic acid. Specific examples of the organic alkaline earth metal salt include Ca, Mg and Ba salts of organic carboxylic acids such as acetic acid and stearic acid, and organic sulfonic acid calcium salts such as calcium dodecylbenzenesulfonate. Ca stearate and Mg acetate are preferred. (D) The amount of the organic alkaline earth metal salt is generally 0.001 part by weight or more, 0.005 part by weight or more, and generally 100 parts by weight of the polyester resin. 1 part by weight or less, preferably 0.8 part by weight or less. It is also preferable that the blending amount is a range in which these ranges are arbitrarily combined. (D) When the blending amount of the organic alkaline earth metal salt is less than 0.001 part by weight, no further improvement effect of heat shock resistance is observed. Sometimes hydrolysis is promoted, the strength begins to decline, and the heat shock resistance also declines.

  The composition of the present invention may contain (E) a reinforcing filler. The use of reinforcing fillers is advantageous in terms of improving mechanical strength, but the anisotropy of the expansion / contraction rate of the contained fillers occurs and the frequency of breakage of molded parts due to temperature changes during use. The problem of increasing Since the polyester resin composition of the present invention has a markedly improved heat shock resistance compared to conventional polyester resin compositions, even when a reinforcing filler is blended, the frequency of breakage of molded products due to temperature changes Can be reduced. Therefore, the resin composition of the present invention has a particularly advantageous effect in the embodiment in which the reinforcing filler is blended.

  Examples of reinforcing fillers include fibrous, plate-like, granular materials, and mixtures thereof. Specifically, fibrous materials such as glass fibers, carbon fibers, mineral fibers, metal fibers, ceramic whiskers, wollastonite; plate-like materials such as glass flakes, mica and talc; silica, alumina, glass beads, carbon black, Well-known things such as granular materials such as calcium carbonate; The standard for selecting the reinforcing filler depends on the properties required for the molded product, but when mechanical strength and rigidity are important, fibrous materials, especially glass fibers, are selected to reduce anisotropy and warpage. If important, plate-like materials, especially mica, are selected. In addition, an optimum granular material is selected in consideration of the overall balance in consideration of fluidity at the time of molding. The glass fiber is not particularly limited as long as it is generally used for resin reinforcement. For example, it can be used by selecting from a long fiber type (roving), a short fiber type (chopped strand) and the like, and the fiber diameter is generally 6 to 13 μm. Further, the glass fiber may be treated with a sizing agent (for example, polyvinyl acetate, polyester, etc.), a coupling agent (for example, silane compound, boron compound, etc.), other surface treatment agents, and the like.

  In the embodiment in which the composition of the present invention contains the reinforcing filler, in order to obtain rigidity or dimensional stability while maintaining the effects of the present invention, the blending amount thereof is 100 parts by weight of the polyester resin. The amount is preferably 1 part by weight or more, more preferably 5 parts by weight or more, and preferably 150 parts by weight or less, more preferably 100 parts by weight or less. Moreover, it is also preferable that the said compounding quantity is the range which combined these ranges arbitrarily.

  The composition of the present invention may contain a halogen-based flame retardant as long as the object of the present invention is not impaired. In the present specification, the term “halogen flame retardant” means a known halogen flame retardant having a halogen atom in the molecule and usually used as a flame retardant, in particular, having a bromine content of 20% by weight. % Or more is preferable.

  Preferred examples of the halogen flame retardant include brominated polycarbonate, brominated epoxy resin, brominated phenoxy resin, brominated polyphenylene ether resin, brominated polystyrene resin, brominated bisphenol A, glycidyl brominated bisphenol A, pentabromobenzyl. Polyacrylates and brominated imides are included. Among these, glycidyl brominated bisphenol A, pentabromobenzyl polyacrylate, and brominated imide are preferable in that they do not inhibit the effect of the (C) epoxy compound.

  When the composition of the present invention contains a halogen-based flame retardant, the blending amount thereof is preferably 5 parts by weight or more with respect to 100 parts by weight of the thermoplastic polyester resin from the viewpoint of the balance between flame retardancy and physical properties. More preferably, it is 7 parts by weight or more, more preferably 8 parts by weight or more, preferably 40 parts by weight or less, more preferably 35 parts by weight or less, and further preferably 25 parts by weight or less. Moreover, it is also preferable that the said compounding quantity is the range which combined these ranges arbitrarily. If the halogen-based flame retardant is less than 5 parts by weight, it is difficult to obtain sufficient flame retardancy, and if it exceeds 40 parts by weight, the physical properties, particularly mechanical strength, tend to decrease.

The composition of the present invention may further contain an antimony compound as a flame retardant aid. Examples of antimony compounds that can be used as flame retardant aids include antimony trioxide (Sb ₂ O ₃ ), antimony pentoxide (Sb ₂ O ₅ ), and sodium antimonate.

  When the composition of the present invention contains an antimony compound, the blending amount thereof is preferably 2 parts by weight or more, more preferably 100 parts by weight of the thermoplastic polyester resin, from the viewpoint of balance between flame retardancy and physical properties. Is 3 parts by weight or more, preferably 40 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 20 parts by weight or less. Moreover, it is preferable that the said compounding quantity is the range which combined these ranges arbitrarily. When the antimony compound is less than 2 parts by weight, it is difficult to obtain sufficient flame retardancy, and when it exceeds 40 parts by weight, the physical properties tend to decrease.

  Moreover, in order to improve heat shock resistance more efficiently, the composition of the present invention may further contain a pentaerythritol ester compound or a carbodiimide compound.

  As described above, the resin composition of the present invention can be (E) reinforced filling as required in addition to (A) polyester resin, (B) acrylic rubber, (C) epoxy compound, and (D) organic alkaline earth metal salt. An agent or a flame retardant may be contained. In addition to reinforcing fillers and flame retardants, various known additives such as paraffin wax, polyethylene wax, stearic acid and esters thereof, silicone oil and the like are used as long as they do not impair the properties of the composition. Type stabilizers; heat stabilizers such as hindered phenols, phosphites, and sulfur-containing ester compounds; crystallization accelerators; UV absorbers or weathering agents; dyes, pigments, foaming agents, etc. Also good. Various nylons such as nylon 6, nylon 66, nylon 12, nylon MXD6, various nylon elastomers, liquid crystal polymers, polycarbonate resins, styrene resins such as polystyrene, ABS, AS, MS, various acrylic resins, polyethylene, polypropylene, ethylene -Olefin resins such as propylene copolymer, fluorine resins such as polytetrafluoroethylene, various elastomers such as isobutylene-isoprene rubber, styrene-butadiene rubber, styrene-butadiene rubber-styrene, ethylene-propylene rubber, acrylic elastomer, etc. Further, it may contain a thermosetting resin such as a phenol resin, a melamine resin, a silicone resin, or an epoxy resin, such as an ionomer resin, a phenoxy resin, or polycaprolactam.

  The resin composition of the present invention can be obtained by blending and kneading the components (A), (B), (C) and (D), and various additive components used as necessary. it can. The blending is performed by a commonly used method, for example, a ribbon blender, a Hensell mixer, a drum blender, or the like. Various extruders, Brabender plastographs, lab plast mills, kneaders, Banbury mixers, etc. are used for melt-kneading. The heating temperature at the time of melt kneading is usually 230 to 290 ° C. In order to suppress decomposition during kneading, it is preferable to use the heat stabilizer. Each component including an additional component can be supplied to the kneader in a lump or can be supplied sequentially. In addition, two or more kinds of components selected from each component, including additional components, can be mixed in advance. By adding a fibrous reinforcing filler such as glass fiber after the resin is melted from the middle of the extruder, it can avoid crushing and exhibit high characteristics.

  The resin composition of the present invention can be produced by various known molding methods such as injection molding, hollow molding, extrusion molding, compression molding, calendar molding, rotational molding, etc., in the electrical / electronic equipment field, automobile field, machine field, medical field. Molded products such as fields can be obtained. A particularly preferable molding method is injection molding because of its good fluidity. In the injection molding, the resin temperature is preferably controlled to 240 to 280 ° C.

  The resin composition of the present invention is preferably used for producing an insert molded product. In insert molding, an insert made of a metal, an inorganic material, a thermosetting resin, or the like is placed in advance in a cavity of a molding die, and a resin composition is filled in a space outside thereof to form a composite molded product. It is a method to do. The method for filling the resin composition into the cavity of the mold is not particularly limited, and various methods such as an injection molding method and an extrusion compression molding method can be used. In general, the injection molding method is used. Is preferred. The material of the insert is not particularly limited, but it is preferable to use a solid made of a metal, an inorganic material, or a thermosetting resin so that it does not melt and deform when it comes into contact with the resin during insert molding. Examples of metals that can be used as the material of the insert include aluminum, magnesium, copper, iron, brass and alloys thereof. Moreover, glass and ceramic are contained in the inorganic material which can be used as a raw material of an insert. Furthermore, there is no restriction | limiting in particular about the thermosetting resin which can be used as a raw material of an insert thing, Various resin can be used. For example, epoxy resin, unsaturated polyester resin, phenol resin, urea resin, melamine resin, polyurethane resin, silicone resin and the like can be mentioned. A metal, an inorganic material, or a thermosetting resin can be used as an insert after being formed into a desired shape in advance.

EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.
Various resin compositions of Examples and Comparative Examples were prepared, and the cylinder temperature was 250 ° C. and the mold temperature was 80 ° C. using an injection molding machine (model SG-75SYCAP-MIII) manufactured by Sumitomo Heavy Industries, Ltd. Under the conditions, a test piece for measuring mechanical properties was molded, and performance evaluation was performed by the following test method. Further, a heat shock resistance test was performed by the method described later. The results are shown in Table 1.

The raw materials used in Examples and Comparative Examples are shown below. In the following examples, “part” means “part by weight”.
(A) As the polyester resin, PBT (polybutylene terephthalate) resin (Mitsubishi Engineering Plastics, “5008”, intrinsic viscosity = 0.85 dl / g, content of titanium atom is 30 ppm) was used.
(B) As an acrylic rubber, (B1) an alkyl acrylate / alkyl methacrylate copolymer (manufactured by Kureha Chemical Industry Co., Ltd., Paraloid EXL2315) was used. Further, instead of acrylic rubber for the comparative example, (B2) EMMA (ethylene / methyl methacrylate copolymer, manufactured by Sumitomo Chemical Co., Ltd., “ACRIFTH WH401”), which is an olefin elastomer, and (B3) SEPS, which is a styrene elastomer. Styrene / polyisoprene copolymer, manufactured by Kuraray, “Septon 2002”) or (B4) MBS (methyl methacrylate / butadiene / styrene copolymer, manufactured by Technopolymer, “MBS61”) was used.
(C) Diglycidyl ether of bisphenol A (manufactured by Asahi Denka, “Adeka Sizer EP-17”) was used as an epoxy compound.
(D) As the organic alkaline earth metal salt, (D1) calcium stearate (manufactured by Wako Pure Chemical Industries) or (D2) magnesium acetate (manufactured by Wako Pure Chemical Industries) was used.
(E) As a reinforcing filler, glass fiber (manufactured by Nippon Electric Glass, “T-187”, fiber diameter 13 μm) was used.

[Performance evaluation method]
(1) Tensile test: Measured according to ISO527. The unit of strength is MPa, and the unit of elongation is%.
(2) Bending test: Measured according to ISO178. The unit of strength and elastic modulus is MPa.
(3) Heat shock test: a rectangular iron insert 1 (16 mm × 33 mm × 3 mm) shown in FIG. As shown in FIG. 2, this was charged into the mold 4 while being supported by the pins 2 and insert molded to produce an insert molded product (18 mm × 35 mm × 5 mm) shown in FIG. The thickness of the resin part of this insert molded product is 1 mm. Two weld lines 6 are generated on the support pin mark 5 in the insert molded product. A DTS-30 heat shock test manufactured by Irie Seisakusho was performed using this insert molded product. Specifically, 5 insert molded products were subjected to heat shocks of 100 cycles, 200 cycles and 300 cycles, with 30 minutes at −40 ° C. and 30 minutes at 130 ° C. as one cycle. The number of cracks in a total of 10 weld lines of the molded product was determined.

[Examples 1-2 and Comparative Examples 1-5]

  Compared with the insert molded product of the comparative example, the insert molded product of the example has remarkably less cracking and the heat shock resistance is remarkably improved. From the results shown in Table 1 above, the compositions of the examples in which (A) polyester resin was blended with specific amounts of (B) acrylic rubber, (C) epoxy compound and (D) organic alkaline earth metal salt were It has been demonstrated that the heat shock properties are significantly improved.

  The molded article comprising the polyester resin composition of the present invention is excellent in mechanical properties and heat shock resistance, is less susceptible to cracking with respect to changes in temperature, and is useful in automobiles such as engine parts. . Therefore, it can be widely used in many fields such as the electric / electronic equipment field, the automobile field, and the machine field.

It is a perspective view of a rectangular parallelepiped iron insert (16 mm × 33 mm × 3 mm) used in the examples. It is the cross-sectional schematic of the metal mold | die in which the insert of the state supported by the support pin was set | placed in the cavity. It is a schematic perspective view of an insert molded product (18 mm × 35 mm × 5 mm) in which two weld lines are generated on the support pin mark.

Explanation of symbols

1. Insert iron piece 2. 2. Support pin Insert 4 Cavity 5. 5. Support pin mark Weld line

Claims (5)

(A) For 100 parts by weight of the polyester resin,
(B) 0.5 to 40 parts by weight of acrylic rubber,
(C) A thermoplastic polyester resin composition containing 0.1 to 20 parts by weight of an epoxy compound and (D) 0.001 to 1 part by weight of an organic alkaline earth metal salt. The thermoplastic polyester resin composition according to claim 1, further comprising (E) a reinforcing filler in an amount of 1 to 150 parts by weight based on 100 parts by weight of the (A) polyester resin. 3. The thermoplastic polyester resin composition according to claim 1 or 2, wherein the organic alkaline earth metal salt is calcium stearate or magnesium acetate. (A) Polyester resin is a polybutylene terephthalate, The thermoplastic polyester resin composition as described in any one of Claims 1-3. An insert-molded product obtained by insert-molding the thermoplastic polyester resin composition according to any one of claims 1 to 4 and a metal, an inorganic solid, or a thermosetting resin solid.

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