JP2007138021A - Thermoplastic resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition which is excellent in outer appearance of a molded product, chemical resistance and mechanical properties, and is suitably applicable to such vehicular exterior components as a door handle, a pillar, a side mall and a side protector. <P>SOLUTION: The thermoplastic resin composition is characterized by the followings. It comprises 20-55 wt.% of a polybutylene terephthalate resin (A), 25-70 wt.% of a polycarbonate resin (B), 5-30 wt.% of mica (C) having 4.0-50 μm average particle diameter and 0.5-30 wt.% of a rubbery polymer (D) on the basis of 100 wt.% of the total thermoplastic resin composition. Where the polybutylene terephthalate resin and the polycarbonate resin have a two-phase continuous structure with 0.01-1.0 μm structural period. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention comprises a polybutylene terephthalate and a polycarbonate resin reinforced with a filler, and the polybutylene terephthalate resin and the polycarbonate resin have a two-phase continuous structure with a structural period of 0.01 to 1.0 μm. The present invention relates to a vehicle exterior part made of a plastic resin composition.

  Conventionally, blends of polybutylene terephthalate resin and polycarbonate resin are widely used as engineering plastics because of their excellent mechanical properties, heat resistance, chemical resistance, and the like. Further, in recent years, in order to improve impact resistance and rigidity, those containing a fine inorganic filler such as rubber polymer, glass fiber, talc, mica, whisker or the like are widely used.

Patent Document 1 proposes a composition comprising a polybutylene terephthalate resin and a polycarbonate resin having a specific structural period. Patent Document 2 proposes a composition obtained by blending a specific glass fiber and a thermoplastic elastic polymer with a composition comprising a polybutylene terephthalate resin and a polycarbonate resin. Patent Document 3 proposes a resin composition in which a rubber-like elastic body and an inorganic filler are blended with a composition comprising a polybutylene terephthalate resin and a polycarbonate resin. However, when the resin composition described in Patent Document 1 is used, the rigidity is insufficient because the inorganic filler is not blended, and when the resin composition described in Patent Document 2 is used. The appearance of the fibrous filler is conspicuous in the appearance, which is insufficient when a good appearance is required. In addition, when the resin composition described in Patent Document 3 is used, it is better than the appearance of the resin composition described in Patent Document 1, but because of its small reinforcing effect, fatigue characteristics, chemical resistance, mechanical characteristics Has the disadvantage of lowering.
JP 2003-286414 A Japanese Patent Application Laid-Open No. 06-49344 Japanese Patent Laid-Open No. 05-222283

  Therefore, the present invention is to provide a thermoplastic resin composition that is excellent in product appearance and has both impact resistance, rigidity, fatigue properties, chemical resistance and mechanical properties.

  The present invention has been obtained as a result of intensive studies by the present inventors in order to solve the above problems.

That is, the present invention
(1) 100% by weight of the entire thermoplastic resin composition,
20 to 55% by weight of polybutylene terephthalate resin (A),
25 to 70% by weight of polycarbonate resin (B)
Mica (C) having an average particle diameter of 4.0 to 50 μm, 5 to 30% by weight,
Rubber polymer (D) 0.5-30% by weight
A thermoplastic resin composition characterized in that the polybutylene terephthalate resin and the polycarbonate resin have a biphasic continuous structure with a structural period of 0.01 to 1.0 μm,
(2) The thermoplastic resin composition according to (1), wherein the mica (C) is surface-treated.
(3) A vehicle exterior component comprising the thermoplastic resin composition described in (1) and (2),
Is to provide.

  The thermoplastic resin composition of the present invention can provide a composition excellent in appearance of a molded product, chemical resistance and mechanical properties. In addition, the thermoplastic composition can be suitably used as a vehicle exterior part such as a door handle, a pillar, a side molding, a side protector.

  Hereinafter, the present invention will be described in detail.

  The polybutylene terephthalate resin (A) constituting the present invention is a normal polymerization such as a polycondensation reaction mainly comprising terephthalic acid or an ester-forming derivative thereof and 1,4-butanediol or an ester-forming derivative thereof. It is a polymer obtained by the method and may contain other copolymerization components in a range that does not impair the characteristics, for example, about 20% by weight or less. Preferred examples of these (co) polymers include polybutylene terephthalate, polybutylene (terephthalate / isophthalate), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decanedicarboxylate), polybutylene ( Terephthalate / naphthalate), poly (butylene / ethylene) terephthalate, and the like. These may be used alone or in combination.

  The polybutylene terephthalate used in the present invention preferably has an intrinsic viscosity of 0.60 to 1.60, particularly 0.80 to 1.30 when an o-chlorophenol solution is measured at 25 ° C. is there. If the intrinsic viscosity is less than 0.60, the mechanical properties are poor. On the other hand, if the intrinsic viscosity exceeds 1.60, the moldability tends to be poor.

The compounding quantity of the polybutylene terephthalate in this invention is 20 to 55 weight% of the whole resin composition. When the blending amount of polybutylene terephthalate is less than 20% by weight, the chemical resistance of the resin composition is inferior, and when it exceeds 55% by weight, the impact strength of the resin composition tends to decrease.
The polycarbonate resin (B) constituting the present invention is a polymer obtained by reacting a dihydric phenol with a carbonate precursor such as phosgene or a carbonate ester compound, for example, in a solvent such as methylene chloride. It is produced by a reaction between a dihydric phenol and a carbonate precursor such as phosgene, or by a transesterification reaction between a dihydric phenol and a carbonate precursor such as diphenyl carbonate. There are various dihydric phenols, and 2,2-bis (4-hydroxyphenyl) propane [bisphenol A] is particularly preferable. Divalent phenols other than bisphenol A include bis (4-hydroxyphenyl) alkane, 1,1- (4-hydroxyphenyl) methane, 1,1- (4-hydroxyphenyl) ethane, hydroquinone, bis (4-hydroxy Phenyl) cycloalkane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, etc. Is mentioned. These dihydric phenols may be used alone or in combination of two or more. Examples of the carbonate compound include diaryl carbonates such as diphenyl carbonate, and dialkyl carbonates such as dimethyl carbonate and diethyl carbonate.

  As the polycarbonate resin (B) used in the present invention, those having an average molecular weight in the range of 10,000 to 60,000, particularly 15,000 to 40,000 are suitable. If the average molecular weight is less than 10,000, the mechanical properties are poor. On the other hand, if the average molecular weight exceeds 60000, the moldability tends to be poor.

  The compounding quantity of polycarbonate resin (B) in this invention is 25 to 70 weight% of the whole resin composition. When the blending amount of the polycarbonate resin (B) is less than 25% by weight, the impact strength of the resin composition tends to be lowered, and when it exceeds 70% by weight, the chemical resistance is lowered, or during the injection molding of the resin composition. The mold release property is poor and the molding high cycle property tends to be inferior.

Examples of mica (C) used in the present invention include muscovite, phlogopite, biotite, artificial mica and the like, and muscovite is particularly preferable. The muscovite is represented by the chemical formula K ₂ Al ₄ (Si ₆ · Al ₂ ) O ₂₀ (OH) ₄ , and has a triple structure including Al and K between the layers of the silicate tetrahedron. ₂ 45.8 _{wt%, Al 2 O 3 35.4%} K 2 O9.1%, other _{Fe 2 O 3, H 2 O} , containing and Na ₂ O.

  In the present invention, the average particle diameter of mica is 4.0 to 50 μm, preferably 4.0 to 30 μm. In the present invention, the particle diameter refers to a numerical value obtained by measuring the particle size distribution by a microtrack laser analysis method and performing number average. If the average particle diameter of mica is less than 4.0 μm, the rigidity is insufficient, and if it is 50 μm or more, the impact resistance is lowered.

  Also, mica is a vinylsilane compound such as vinyltriethoxysilane, vinyltrichlorosilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltri. Epoxysilane compounds such as methoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, aminosilane compounds such as γ-aminopropyltrimethoxysilane, stearic acid Those subjected to surface treatment with long-chain fatty acids such as oleic acid, montanic acid, stearyl alcohol or long-chain aliphatic alcohols are preferably used.

  The amount of mica in the present invention is 5 to 30% by weight of the entire resin composition. If the amount of mica is less than 5% by weight, the rigidity is insufficient, and if it is 30% by weight or more, the appearance deteriorates due to the floating of the filler.

  Furthermore, in the present invention, it is essential to use the rubbery polymer (D) in order to improve the impact strength. Such a rubbery polymer is a resin that exhibits rubber elasticity at room temperature, and is a polybutadiene, polyisobrene, random copolymer of styrene-butadiene and a block copolymer, a hydrogenated product of the block copolymer, acrylonitrile-butadiene. Copolymers, diene rubbers such as butadiene-isoprene copolymers, ethylene-propylene random copolymers and block copolymers, ethylene-butene random copolymers and block copolymers, and ethylene-α olefins Copolymers, copolymers with ethylene-unsaturated carboxylic esters such as ethylene-methacrylate, ethylene-butyl acrylate, acrylic ester-butadiene copolymers, for example acrylic rubbers such as butyl acrylate-butadiene copolymers, etc. Can be mentioned. Particularly, bulk polymerization, suspension polymerization, bulk suspension polymerization, solution of one or more of methacrylic acid ester, aromatic monovinyl compound, and vinyl cyanide compound to butadiene rubber-like polymer such as polybutadiene and butadiene-styrene copolymer An MBS resin obtained by graft polymerization by a method such as polymerization or emulsion polymerization, particularly an emulsion polymerization method is preferred.

  The compounding quantity of the rubber-like polymer (D) in this invention is 0.5 to 30 weight% of the whole resin composition. When the blending amount of the rubber polymer (D) is less than 0.5% by weight, the impact strength is insufficient, and when it exceeds 30% by weight, the chemical resistance is lowered, or the mold release at the time of injection molding of the resin composition. The properties are poor and the molding high cycle property tends to be inferior.

In the present invention, it is essential that the polybutylene terephthalate resin and the polycarbonate resin have a two-phase continuous structure with a structural period of 0.01 to 1.0 μm. As a method for obtaining a polymer alloy having such a structure, a method utilizing spinodal decomposition described later is preferable.

In general, polymer alloys composed of two-component resins include compatible systems, incompatible systems, and semi-compatible systems. The compatible system is a system that is compatible in the entire range of practical temperatures above the glass transition temperature and below the thermal decomposition temperature under non-shearing in an equilibrium state. The incompatible system is a system that is incompatible in the entire region, contrary to the compatible system. A semi-compatible system is a system that is compatible in a certain temperature and composition region and incompatible in another region. Furthermore, in this semi-compatible system, there are those that undergo phase separation by spinodal decomposition depending on the conditions of the phase separation state and those that undergo phase separation by nucleation and growth.

Furthermore, in the case of a polymer alloy comprising three or more components, a system in which all of the three or more components are compatible, a system in which all of the three or more components are incompatible, and a compatible system having two or more components and the rest There is a system in which one or more phases are incompatible with each other, two components are in a semi-compatible system, and the remaining components are distributed in a semi-compatible system composed of these two components.
In the present invention, in the case of a polymer alloy comprising three or more components other than polybutylene terephthalate resin and polycarbonate resin, the third component other than polybutylene terephthalate resin and polycarbonate resin is at least one of polybutylene terephthalate resin and polycarbonate resin. A distributed system is preferred. In this case, the structure of the polymer alloy is equivalent to the incompatible structure composed of two components. The following description will be made on behalf of a polymer alloy composed of a two-component resin.

In the above incompatible system, it is possible to induce spinodal decomposition by melt kneading, and this is achieved by once compatibilizing under shear at a shear rate of 100 to 10000 sec ⁻¹ during melt kneading and then under non-shearing. The phases are separated by the so-called shear field-dependent spinodal decomposition in which the phase decomposition occurs. Since the basic part of this shear field-dependent spinodal decomposition mode is the same as the above-described general spinodal decomposition in the semi-compatible system, the spinodal decomposition in the general semi-compatible system is described below, and then the present invention is applied. A description will be given in the form of appending characteristic portions.

  In general, phase separation by spinodal decomposition refers to phase separation that occurs in an unstable state inside the spinodal curve in phase diagrams for different two-component resin compositions and temperatures. On the other hand, phase separation by nucleation and growth refers to phase separation that occurs in the metastable state inside the binodal curve and outside the spinodal curve in the phase diagram.

The spinodal curve refers to the difference (ΔGmix) between the free energy in the case of being compatible and the sum of the free energy in the incompatible phase (ΔGmix) when mixing two different resins with respect to the composition and temperature. This is a curve in which the partial differential of (φ ² ) (∂ ² ΔGmix / ∂φ ² ) becomes zero. Inside the spinodal curve, 不 安定² ΔGmix / ∂φ ² <0 is in an unstable state, and outside the spinodal curve, ∂ ² ΔGmix / ∂φ ² > 0.

  The binodal curve is a curve at the boundary between a region where the system is compatible and a region where it is incompatible with the composition and temperature.

  Here, the compatible state is a state in which they are uniformly mixed at the molecular level. Specifically, the case where the phase which consists of a different component does not form the structure of 0.001 micrometer or more is pointed out. Moreover, an incompatible state is a case where it is not a compatible state. That is, the phase which consists of a different component points out the state which forms the structure of 0.001 micrometer or more. Here, the structure of 0.001 μm or more is, for example, a two-phase continuous structure having a structural period of 0.001 to 1 μm or a dispersed structure having a distance between particles of 0.001 to 1 μm. Whether or not they are compatible is determined by, for example, an electron microscope, a differential scanning calorimeter (DSC), and various other methods as described in Polymer Alloys and Blends, Leszek A Utracki, hanser Publishers, Munich Viema New York, P64. be able to.

In order to realize the spinodal decomposition, it is necessary that the resin having two or more components is once in a compatible state and then in an unstable state inside the spinodal curve. In spinodal decomposition in a general semi-compatible system, spinodal decomposition can be caused by temperature jumping to an incompatible region after melt-kneading under compatible conditions. On the other hand, in the above-mentioned shear field-dependent spinodal decomposition, in the non-compatible system, since it is compatibilized under shear in the range of a shear rate of 100 to 10000 sec ⁻¹ at the time of melt kneading, the spinodal can be obtained only by non-shear. Degradation can occur.
The polymer alloy formed by blending the polybutylene terephthalate resin and the polycarbonate resin of the present invention belongs to the above-mentioned shear field-dependent spinodal decomposition, and is compatibilized under shear in the range of a shear rate of 100 to 10000 sec ⁻¹ during melt kneading. Only under non-shearing can cause spinodal decomposition. In the above, the shear rate is, for example, when using a parallel disk type shear applicator, a resin heated to a predetermined temperature and put in a molten state is put between the parallel disks, the distance (r) from the center, and between the parallel disks It can be obtained as ω × r / h from the interval (h) and the angular velocity (ω) of rotation.

  As a specific method for producing such a polymer alloy, a method using the above-described shear field-dependent spinodal decomposition can be cited as a preferred example. A preferable method is a method of melt-kneading under high shear stress in the kneading zone of the twin-screw extruder.

  When using such a twin-screw extruder, a higher shear stress state is formed by screw arrangement using a kneading block, lowering the resin temperature, increasing the screw rotation speed, or increasing the viscosity of the polymer used. Therefore, it can be adjusted appropriately. In the polyester resin composition of the present invention, a mold release agent, an antioxidant, a stabilizer, an ultraviolet absorber, a colorant, a flame retardant, a flame retardant aid, an impact modifier, within the range not impairing the effects of the present invention Conventional additives such as lubricants and small amounts of other polymers can be added.

  Release agents include plant waxes such as carnauba wax and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as montan wax, petroleum waxes such as paraffin wax and polyethylene wax, castor oil and its Fatty waxes such as derivatives, fatty acids and derivatives thereof may be mentioned.

  Examples of antioxidants include 2,6-di-t-butyl-4-methylphenol, tetrakis (methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) methane, tris Phenol compounds such as (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, sulfur such as dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate And phosphorous compounds such as trisnonylphenyl phosphite and distearyl pentaerythritol diphosphite.

  Stabilizers include benzotriazole compounds including 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, and benzophenone compounds such as 2,4-dihydroxybenzophenone, mono- or distearyl phosphate, trimethyl phosphate And phosphoric acid esters.

  These various additives may have a synergistic effect by combining two or more kinds, and may be used in combination.

  For example, the additive exemplified as the antioxidant may act as a stabilizer or an ultraviolet absorber. Some of those exemplified as stabilizers also have an antioxidant action and an ultraviolet absorption action. That is, the above classification is for convenience and does not limit the action.

  Examples of the ultraviolet absorber include 2-hydroxy-4-n-dodecyloxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, and bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane. Benzophenone-based ultraviolet absorbers typified by, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) Benzotriazole, 2- (2′-hydroxy-3 ′, 5′-bis (α, α′-dimethylbenzyl) phenylbenzotriazole, 2,2′methylenebis [4- (1,1,3,3-tetramethyl) Butyl) -6- (2H-benzotriazol-2-yl) phenol], methyl-3- [3-tert-butyl-5 The benzotriazole type ultraviolet absorber represented by the condensate with-(2H-benzotriazol-2-yl) -4-hydroxyphenylpropionate-polyethylene glycol can be mentioned.

  Also, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6- Tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetra Carboxylate, poly {[6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl] [(2,2,6,6-tetramethylpiperidyl ) Imino] hexamethylene [(2,2,6,6-tetramethylpiperidyl) imino]}, polymethylpropyl 3-oxy- [4- (2,2,6,6-tetramethyl) piperidinyl] siloxane. It can also include hindered amine light stabilizers represented by, such light stabilizers in combination with the ultraviolet absorber and various antioxidants, exhibit better performance in terms of weather resistance.

  Flame retardants are halogen-based, phosphoric ester-based, metal salt-based, red phosphorus, silicon-based, metal hydrate-based, and the like, and also include anti-dripping agents. Examples of the colorant include organic dyes, organic pigments, and inorganic pigments. Other examples include fluorescent brighteners, phosphorescent pigments, fluorescent dyes, flow modifiers, inorganic and organic antibacterial agents, photocatalytic antifouling agents, impact modifiers such as graft rubber, infrared absorbers, and photochromic agents. be able to.

In the thermoplastic resin composition of the present invention, these blending components are preferably dispersed uniformly, and any blending method can be used. A typical example is a method of melt-kneading at a temperature of 200 to 350 ° C. using a known melt mixer such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, or a mixing roll. Each component may be mixed in advance and then melt kneaded. In addition, although it is better that the water | moisture content adhering to each component is less and it is desirable to dry beforehand, not all the components need to be dried.

As an example of a preferable production method of the thermoplastic polyamide resin composition of the present invention, a raw material in which (A) to (D) and other additives are blended using a twin-screw extruder having a cylinder temperature of 230 to 300 ° C. is used. Examples include a method of supplying to an extruder and kneading, and a more preferable production method includes a method using shear field-dependent spinodal decomposition, and a method of realizing compatibilization during melt-kneading is a polybutylene terephthalate resin. And a polycarbonate resin in a kneading zone of a twin screw extruder under a high shear stress. The vehicular exterior part of the present invention is generally molded by a known thermoplastic resin molding method such as injection molding, extrusion molding, blow molding, transfer molding, vacuum molding, etc., among which injection molding is preferable. In the case of producing by injection molding, it is preferable that the cylinder temperature is about 20 ° C. to 50 ° C. higher than the melting point of the resin composition, and the mold temperature is 60 to 120 ° C.

  The thermoplastic resin composition of the present invention is excellent in appearance, chemical resistance and mechanical properties, and can be suitably used as exterior parts for vehicles such as door handles, pillars, side moldings and side protectors.

  Hereinafter, the present invention will be described in more detail with reference to examples.

  The evaluation method of an Example and a comparative example is shown next.

(1) Confirmation of structure period About a 3 mm thick square plate injection-molded under conditions of a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C., a 100 μm thick section was cut out, stained with polycarbonate by iodine staining, and then transmission electron microscope The observation was performed at a magnification of 100,000 times.

(2) Appearance evaluation A 3 mm thick square plate injection-molded under the conditions of a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C. is visually confirmed to have no brightness of filler on the surface and excellent in brightness. In addition, the case where floating of filler was observed on the surface was rated as x.

(3) Evaluation of chemical resistance A bending test piece of length × width × thickness = 128 mm × 12.8 mm × 3.2 mm molded under conditions of a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C. was wax remover 50%. It was immersed in a diluent for 72 hours, and the bending strength was evaluated by a method based on ASTM D790.

(4) Evaluation of Tensile Strength and Tensile Elongation The bending strength of the ASTM No. 1 test piece, which was injection molded under the conditions of a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., was evaluated according to ASTM D638.

(5) Evaluation of impact resistance (Izod impact strength) A test piece for Izod impact test having a thickness of 3.0 mm was injection molded under the conditions of a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C. and used as a sample. The notched Izod impact strength was measured according to ASTM D256.

(6) Evaluation of rigidity (flexural modulus)
Bending elastic modulus of a bending test piece of length × width × thickness = 128 mm × 12.8 mm × 3.2 mm, which was injection-molded under conditions of a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., was evaluated by a method in accordance with ASTM D790. did.

The compounding composition used for the Example and the comparative example below is shown.
(A-1) Polybutylene terephthalate resin: “Toraycon 1200S” manufactured by Toray Industries, Inc., and intrinsic viscosity 1.25 (hereinafter also referred to as PBT)
(B-1) Aromatic polycarbonate resin: “A2600” manufactured by Idemitsu Chemical Co., Ltd.
Number average molecular weight 26000 (hereinafter also referred to as PC)
(C-1) Mica: “A-21” manufactured by Yamaguchi Mica Co., Ltd., average particle size = 22.5 μm, epoxy silane surface treatment (C-2) Mica: “A-21” manufactured by Yamaguchi Mica Co., Ltd. Average particle diameter = 22.5 μm, no surface treatment (C-3) Mica: “A-11” manufactured by Yamaguchi Mica Co., Ltd., average particle diameter = 5.2 μm, epoxysilane surface treatment (C-4) Mica: Yamaguchi “A-61” manufactured by Mica Co., Ltd., average particle size = 51.1 μm, epoxy silane surface treatment (D-1) Rubber polymer: “M-511” manufactured by Kaneka Chemical Co., Ltd., average particle size = 0.66 μm
(E-1) Glass fiber (GF): “T-187” manufactured by Nippon Electric Glass Co., Ltd.
(F-1) Talc: “Micron White 5000A” manufactured by Hayashi Kasei Co., Ltd.
Examples 1-6
(A) to (D) were blended in combinations shown in Table 1. The manufacturing method of the material described in each Example is as follows. That is, it was manufactured using a twin screw extruder with a screw diameter of 57 mmφ set at a cylinder temperature of 250 ° C. Components (A), (B) and (D), and other additives are all fed from the base, the component (C) is supplied from the side feeder, melt kneaded, and the strand discharged from the die is cooled in a cooling bath. And then pelletized with a strand cutter. Each of the obtained pellets was dried for 3 hours or more with a hot air dryer at 130 ° C., and then molded and evaluated using the method described in the evaluation method.

  The results are also shown in Table 1. All of the obtained compositions were excellent in appearance, chemical resistance, tensile strength, tensile elongation, impact strength, and flexural modulus.

Comparative Examples 1-6
Table 2 shows the formulation of the comparative example and the evaluation results.

  Except that the composition of the resin composition was changed as shown in Table 2, pelletization and molding were performed in the same manner as in Examples, and various evaluations were performed. The obtained composition was inferior in any of appearance, chemical resistance, tensile strength, tensile elongation, impact strength, and flexural modulus.

Claims (3)

100% by weight of the entire thermoplastic resin composition,
20 to 55% by weight of polybutylene terephthalate resin (A),
25 to 70% by weight of polycarbonate resin (B)
Mica (C) having an average particle diameter of 4.0 to 50 μm, 5 to 30% by weight,
Rubber polymer (D) 0.5-30% by weight
A thermoplastic resin composition comprising a polybutylene terephthalate resin and a polycarbonate resin having a biphasic continuous structure having a structural period of 0.01 to 1.0 μm. The thermoplastic resin composition according to claim 1, wherein the mica (C) is surface-treated. An exterior part for a vehicle comprising the thermoplastic resin composition according to claim 1.