JP2020019950A - Polybutylene terephthalate resin composition and method for producing the same, and metal resin composite - Google Patents

Abstract

To provide a polybutylene terephthalate resin composition that has excellent impact resistance, and shows alkali resistance and excellent heat shock resistance and a method for producing the same, and a metal resin composite.SOLUTION: A polybutylene terephthalate resin composition is characterized by containing (B) 5-30 parts by mass of an elastomer, (C) 0.3-4 parts by mass of an epoxy compound, (D) 15-80 parts by mass of a reinforcing filler, and (E) 1-15 parts by mass of a master batch including a thermoplastic resin and a silicone compound having a weight-average molecular weight of 10000-80000, with respect to (A) 100 parts by mass of a polybutylene terephthalate resin.SELECTED DRAWING: None

Description

  TECHNICAL FIELD The present invention relates to a polybutylene terephthalate resin composition, and in particular, has excellent impact resistance, and exhibits excellent resistance under an alkaline environment (hereinafter, also referred to as “alkali resistance”) and excellent heat shock resistance. The present invention relates to a polybutylene terephthalate resin composition, a method for producing the same, and a metal resin composite.

  Polybutylene terephthalate resin is easy to process, has excellent mechanical and physical properties, heat resistance, and other physical and chemical properties. Therefore, it is used for automotive parts, electrical and electronic equipment parts, building material parts, and other precision equipment parts. Widely used in the field. For example, in the automotive field, connectors, distributor parts, ignition coil parts and other parts around the engine, various control units, various sensors, electrical and electronic equipment parts include connectors, switch parts, relay parts, coil parts, and building material parts. Polybutylene terephthalate resin is used in a wide range of fields such as sanitary parts and concrete embedded bolts.

  In such a field, particularly for automotive parts for automobiles, moisture-heat resistance (hydrolysis resistance) has been required. To meet this requirement, hydrolysis resistance is improved by using a polybutylene terephthalate resin with a small amount of carboxyl end groups or by capping the carboxyl end groups by reacting the carboxyl end groups with a specific compound. Can be done.

However, polybutylene terephthalate resin has insufficient alkali resistance, especially its long-term durability, and its use environment and use are limited. For example, depending on the use of the resin molded product, the resin molded product may be used in contact with chemicals such as a snow melting agent, a toilet detergent, a bathroom detergent, a bleach, and cement. In particular, in glass fiber reinforced products, the strength is significantly reduced by alkali, and deterioration in an alkaline environment is regarded as a problem.
In addition, in the case of a component made of polybutylene terephthalate resin, there is a possibility that cracks may be generated or finally destroyed due to the action of an alkaline substance, particularly in a thin portion or a portion where distortion remains.

  For example, in the case of a so-called metal insert product in which a metal and a resin are combined, shrinkage occurs during cooling, so that residual strain occurs at the gate portion, and distortion at the metal-resin interface easily occurs, particularly at corners and welds. , Easy to crack. In addition, there is a problem that a molded product that has thermally expanded at a high temperature during molding is thermally contracted in a low temperature environment, that is, a so-called heat shock causes a crack to be generated at a corner portion, a weld portion, or a portion near a gate of the molded product.

  Patent Document 1 discloses (A) a thermoplastic polyester resin, (B) 1 to 25% by mass of an impact resistance imparting agent, (C) 0.1 to 15% by mass of a silicone compound and / or a fluorine compound, A) a thermoplastic polyester resin composition containing 1 to 50% by mass of an inorganic filler and 0.1 to 10% by mass of a polyfunctional compound such as (E) a bisphenol A type epoxy resin, an isocyanate compound and a carboxylic dianhydride; It is disclosed that it has excellent alkali resistance. However, in such a resin composition, the alkali resistance and the heat shock resistance are not at a sufficiently satisfactory level, and the surface appearance accompanying the exudation of the silicone compound or the fluorine compound tends to be reduced.

  Light weight and high performance of products are rapidly progressing, and even if these molded products are made thinner and smaller, it is necessary to exhibit sufficient characteristics over a long period of time. Therefore, at present, there is a need for a polybutylene terephthalate resin composition which does not crack even in a thin portion or a portion where distortion remains, and has excellent alkali resistance and heat shock resistance.

International Publication WO00 / 078867

In particular, in recent years, very high levels of specifications for alkali resistance and heat shock resistance have been required. For example, in the alkali resistance test, although details will be described later, when the insert molded product is immersed in a 10% by mass NaOH aqueous solution, the time until crack generation is 300 hours or more, and the heat shock resistance test (−40) It is also required to meet an extremely strict standard of 200 cycles or more in the number of cycles of crack generation on a weld line by a heat cycle of 130 ° C. × 30 minutes → 130 ° C. × 30 minutes.
The present invention solves the above-mentioned problems of the prior art, improves simultaneously the above-mentioned high alkali resistance and heat shock resistance, and provides a polybutylene terephthalate resin composition excellent in impact resistance and a method for producing the same, and It is an object of the present invention to provide a metal resin composite.

The present inventor has made intensive studies to solve the above-mentioned problems, and as a result, contains (B) an elastomer, (C) an epoxy compound, (D) a reinforcing filler, and a specific silicone compound. By improving the heat shock resistance, especially by compounding the silicone compound as a masterbatch with a thermoplastic resin, the dispersibility of the silicone compound is improved, bleed out and poor appearance are suppressed, The inventors have found that the increase in strain is suppressed and the heat shock resistance is greatly improved, and the present invention has been achieved.
The present invention relates to the following polybutylene terephthalate resin composition, a method for producing the same, and a metal resin composite.

[1] (B) 5 to 30 parts by mass of elastomer, (C) 0.3 to 4 parts by mass of epoxy compound, (D) 15 to 80 parts by mass of reinforcing filler, based on 100 parts by mass of polybutylene terephthalate resin (A). And (E) a polybutylene terephthalate resin composition comprising 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin.
[2] The polybutylene terephthalate resin composition according to the above [1], wherein the epoxy compound (C) is a novolak type epoxy compound.
[3] The polybutylene terephthalate resin composition according to the above [1] or [2], wherein the thermoplastic resin of the master batch (E) is incompatible with the polybutylene terephthalate resin.
[4] The polybutylene terephthalate resin composition according to any one of the above [1] to [3], wherein the thermoplastic resin of the master batch (E) is a polyolefin resin.
[5] (B) 5 to 30 parts by mass of elastomer, (C) 0.3 to 4 parts by mass of epoxy compound, (D) 15 to 80 parts by mass of reinforcing filler, based on 100 parts by mass of polybutylene terephthalate resin. And (E) 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin, followed by melting and kneading, wherein polybutylene terephthalate resin is used. A method for producing the composition.
[6] In at least a part of the metal member, (B) 5 to 30 parts by mass of the elastomer, (C) 0.3 to 4 parts by mass of the epoxy compound, and (D) with respect to 100 parts by mass of the polybutylene terephthalate resin. A resin layer comprising a resin composition containing 1 to 15 parts by mass of a master batch containing 15 to 80 parts by mass of a reinforcing filler and (E) a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin is joined. , Metal-resin composite.

The polybutylene terephthalate resin composition of the present invention has significantly improved both alkali resistance and heat shock resistance, and also has excellent impact resistance.
Therefore, the polybutylene terephthalate resin composition of the present invention can be applied to a wide range of fields such as the field for vehicles (particularly, the field of automobiles), the field of electric and electronics, and the field of building materials. In particular, it has excellent alkali resistance, heat shock resistance and impact resistance as molded articles of vehicle-mounted parts such as connectors, distributor parts, ignition coil parts, control unit parts, and sensor parts.
ADVANTAGE OF THE INVENTION According to the manufacturing method of the polybutylene terephthalate resin composition of this invention, both alkali resistance and heat shock resistance are remarkably improved, and the polybutylene terephthalate resin composition excellent in impact resistance can be provided.
Further, the metal-resin composite of the present invention has extremely high alkali resistance and heat shock resistance.

It is a schematic diagram of a rectangular parallelepiped iron insert used for evaluation of heat shock resistance and alkali resistance in Examples. It is sectional explanatory drawing of the metal mold cavity in which the insert was supported by the support pin. It is a schematic diagram of an insert molded product in which two weld lines are generated in the support pin trace.

  Hereinafter, the contents of the present invention will be described in detail. In this specification, “to” is used to mean that the numerical values described before and after it are included as the lower limit and the upper limit.

  The polybutylene terephthalate resin composition of the present invention comprises (B) 5 to 30 parts by mass of an elastomer, (C) 0.3 to 4 parts by mass of an epoxy compound, and (D) based on 100 parts by mass of the polybutylene terephthalate resin (A). It is characterized by containing 15 to 80 parts by mass of a reinforcing filler, and (E) 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin.

[(A) polybutylene terephthalate resin]
The polybutylene terephthalate resin (A) used in the polybutylene terephthalate resin composition of the present invention is a polyester resin having a structure in which terephthalic acid units and 1,4-butanediol units are ester-bonded. Polymer), a polybutylene terephthalate copolymer containing other copolymer components other than terephthalic acid units and 1,4-butanediol units, and a mixture of a homopolymer and the copolymer.

  (A) The polybutylene terephthalate resin may contain a dicarboxylic acid unit other than terephthalic acid. Specific examples of other dicarboxylic acids include isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, and 2,5. -Naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, biphenyl-2,2'-dicarboxylic acid, biphenyl-3,3'-dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid, bis (4,4'- Carboxyphenyl) methane, anthracene dicarboxylic acid, aromatic dicarboxylic acids such as 4,4′-diphenyl ether dicarboxylic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 4,4′-dicyclohexyl dicarboxylic acid, And aliphatic diacids such as adipic acid, sebacic acid, azelaic acid, and dimer acid. Carboxylic acids, and the like.

  As the diol unit, other diol units may be contained in addition to 1,4-butanediol. Specific examples of the other diol units include aliphatic or alicyclic diols having 2 to 20 carbon atoms. And bisphenol derivatives. Specific examples include ethylene glycol, propylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, cyclohexanedimethanol, 4,4′-dicyclohexylhydroxymethane, , 4′-Dicyclohexylhydroxypropane, ethylene oxide-added diol of bisphenol A, and the like. In addition to the above-mentioned bifunctional monomers, trimellitic acid for introducing a branched structure, trimesic acid, pyromellitic acid, pentaerythritol, trifunctional monomers such as trimethylolpropane and fatty acids for controlling the molecular weight. A small amount of a monofunctional compound may be used in combination.

(A) As described above, the polybutylene terephthalate resin is preferably a polybutylene terephthalate homopolymer obtained by polycondensation of terephthalic acid and 1,4-butanediol. May be a polybutylene terephthalate copolymer containing one or more dicarboxylic acids and / or one or more diols other than 1,4-butanediol as the diol unit, wherein (A) the polybutylene terephthalate resin is In the case of a polybutylene terephthalate resin modified by polymerization, specific preferred copolymers thereof include polyalkylene glycols, particularly polyester ether resins copolymerized with polytetramethylene glycol, and dimer acid copolymerized polybutylene terephthalate. Resin and isophthalic acid If polybutylene terephthalate resin. Among them, it is preferable to use a polyester ether resin obtained by copolymerizing polytetramethylene glycol.
In addition, these copolymers have a copolymerization amount of 1 mol% or more and less than 50 mol% in all segments of the polybutylene terephthalate resin. Among them, the copolymerization amount is preferably 2 mol% or more and less than 50 mol%, more preferably 3 to 40 mol%, and particularly preferably 5 to 20 mol%. With such a copolymerization ratio, fluidity, toughness, and tracking resistance tend to be easily improved, which is preferable.

  (A) In the polybutylene terephthalate resin, the amount of terminal carboxyl groups may be appropriately selected and determined, but is usually 60 eq / ton or less, preferably 50 eq / ton or less, and more preferably 30 eq / ton or less. Is more preferable. When it exceeds 50 eq / ton, alkali resistance and hydrolysis resistance are reduced, and gas is easily generated during melt molding of the resin composition. The lower limit of the amount of terminal carboxyl groups is not particularly limited, but is usually 10 eq / ton in consideration of the productivity of the production of polybutylene terephthalate resin.

  The amount of terminal carboxyl groups of the polybutylene terephthalate resin is a value measured by dissolving 0.5 g of the polyalkylene terephthalate resin in 25 mL of benzyl alcohol and titrating with a 0.01 mol / l benzyl alcohol solution of sodium hydroxide. is there. As a method for adjusting the amount of terminal carboxyl groups, a conventionally known arbitrary method such as a method for adjusting polymerization conditions such as a raw material charging ratio during polymerization, a polymerization temperature, a pressure reduction method, and a method for reacting a terminal blocking agent is used. Just do it.

(A) The intrinsic viscosity of the polybutylene terephthalate resin is preferably 0.5 to 2 dl / g. From the viewpoint of moldability and mechanical properties, those having an intrinsic viscosity in the range of 0.6 to 1.5 dl / g are more preferable. When a resin composition having an intrinsic viscosity lower than 0.5 dl / g is used, the resulting resin composition tends to have low mechanical strength. On the other hand, if it is higher than 2 dl / g, the fluidity of the resin composition may deteriorate, and the moldability may deteriorate.
The intrinsic viscosity of (A) the polybutylene terephthalate resin is a value measured at 30 ° C. in a 1: 1 (mass ratio) mixed solvent of tetrachloroethane and phenol.

(A) Polybutylene terephthalate resin is obtained by melt-polymerizing a dicarboxylic acid component or its ester derivative containing terephthalic acid as a main component and a diol component containing 1,4-butanediol as a main component in a batch or continuous manner. Can be manufactured. In addition, the degree of polymerization (or molecular weight) can be increased to a desired value by producing a low-molecular-weight polybutylene terephthalate resin by melt polymerization and then performing solid-phase polymerization under a nitrogen stream or under reduced pressure.
(A) Polybutylene terephthalate resin is obtained by a production method in which a dicarboxylic acid component mainly containing terephthalic acid and a diol component mainly containing 1,4-butanediol are melt-polycondensed in a continuous manner. Is preferred.

  The catalyst used for performing the esterification reaction may be a conventionally known catalyst, and examples thereof include a titanium compound, a tin compound, a magnesium compound, and a calcium compound. Particularly preferred among these are titanium compounds. Specific examples of the titanium compound as the esterification catalyst include, for example, titanium alcoholates such as tetramethyl titanate, tetraisopropyl titanate and tetrabutyl titanate, and titanium phenolates such as tetraphenyl titanate.

[(B) elastomer]
As the (B) elastomer used in the present invention, a thermoplastic elastomer which is blended with a polyester resin and used to improve the impact resistance may be used. For example, a rubbery polymer or a rubbery polymer may be used. Can be used.
(B) The glass transition temperature of the elastomer is preferably 0 ° C or lower, particularly preferably -20 ° C or lower.

(B) Specific examples of the elastomer include, for example, a copolymer of ethylene and an unsaturated carboxylic acid ester (ethylene-methacrylate copolymer, ethylene-butyl acrylate copolymer, etc.), and a copolymer of ethylene and an aliphatic vinyl compound. Copolymer, terpolymer of ethylene, propylene and non-conjugated diene, acrylic rubber (polybutyl acrylate, poly (2-ethylhexyl acrylate), butyl acrylate-2-ethylhexyl acrylate copolymer, etc.), polybutadiene, polyisoprene, diene Copolymers (styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acryl-butadiene rubber, etc.), copolymers of ethylene and α-olefins having 3 or more carbon atoms (ethylene-propylene copolymer, ethylene -Butene copolymer, ethylene Octene copolymers), silicone rubber (a polyorganosiloxane rubber, a polyorganosiloxane rubber and a polyalkyl (meth) IPN type composite rubber consisting of acrylate rubber), and the like. These may be used alone or in combination of two or more.
In this specification, (meth) acrylate means acrylate and methacrylate, and (meth) acrylic acid means acrylic acid and methacrylic acid.

  Another example of the elastomer (B) is a copolymer obtained by polymerizing a monomer compound on a rubber polymer. Examples of the monomer compound include an aromatic vinyl compound, a vinyl cyanide compound, a (meth) acrylate compound, and a (meth) acrylate compound. Also, epoxy group-containing (meth) acrylate compounds such as glycidyl (meth) acrylate; maleimide compounds such as maleimide, N-methylmaleimide and N-phenylmaleimide; α, β- such as maleic acid, phthalic acid and itaconic acid; Unsaturated carboxylic acid compounds and their anhydrides (for example, maleic anhydride and the like) are also included. These monomer compounds can be used alone or in combination of two or more.

(B) As the elastomer, a copolymer of ethylene and an unsaturated carboxylic acid ester is preferable, an ethylene-alkyl acrylate copolymer is preferable, and an ethylene-butyl acrylate copolymer is particularly preferable. The content of butyl acrylate is preferably 10% by mass or more, and more preferably 20% by mass or more, from the viewpoint of improving impact resistance and heat shock resistance. Further, the MFR of the ethylene-butyl acrylate copolymer is preferably 10 g / 10 min or more, particularly preferably 20 g / min or more, from the viewpoint of improving fluidity.
The use of such an elastomer is preferable because the impact resistance, fluidity, and heat shock resistance tend to be improved.
These elastomers may be used alone or in combination of two or more.

  The content of the elastomer (B) is 5 to 30 parts by mass based on 100 parts by mass of the polybutylene terephthalate resin (A). (B) If the content of the elastomer is less than 5 parts by mass, the effect of improving impact resistance and heat shock resistance is small, and if it exceeds 30 parts by mass, heat aging resistance and rigidity, and further, fluidity and flame retardancy are reduced. I do. The preferred content of the (B) elastomer is 7 parts by mass or more, further 10 parts by mass or more, 25 parts by mass or less, and further 20 parts by mass or less.

[(C) epoxy compound]
The epoxy compound (C) used in the present invention is used for suppressing the polybutylene terephthalate resin from being hydrolyzed to cause a decrease in molecular weight and a decrease in mechanical strength at the same time. Thereby, the synergistic effect of the masterbatch containing the thermoplastic resin and the elastomer (B) and the silicone compound (E) is promoted, and the alkali resistance and the heat shock resistance can be further improved.

(C) The epoxy compound may be any one having at least one epoxy group in one molecule, and is usually a glycidyl compound which is a reaction product of an alcohol, a phenol, a carboxylic acid or the like with epichlorohydrin, A compound obtained by epoxidizing an olefinic double bond may be used.
(C) Epoxy compounds include, for example, novolak type epoxy compounds, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, alicyclic epoxy compounds, glycidyl ethers, glycidyl esters, epoxidized butadiene polymers, resorcinol type epoxy And the like.

Examples of the novolak epoxy compound include a phenol novolak epoxy compound and a cresol novolak epoxy compound.
Examples of the bisphenol A type epoxy compound include bisphenol A-diglycidyl ether and hydrogenated bisphenol A-diglycidyl ether. Examples of the bisphenol F type epoxy compound include bisphenol F-diglycidyl ether and hydrogenated bisphenol F-diglycidyl. Ether and the like.

  Examples of the alicyclic epoxy compound include vinylcyclohexene dioxide, dicyclopentadiene oxide, 3,4-epoxycyclohexyl-3,4-cyclohexylcarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, vinylcyclohexenedioxide Epoxide, 3,4-epoxycyclohexyl glycidyl ether and the like can be mentioned.

  Specific examples of glycidyl ethers include monoglycidyl ethers such as methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether, phenyl glycidyl ether, butyl phenyl glycidyl ether, and allyl glycidyl ether; Examples thereof include diglycidyl ethers such as pentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerin diglycidyl ether, propylene glycol diglycidyl ether, and bisphenol A diglycidyl ether.

  Examples of the glycidyl esters include monoglycidyl esters such as glycidyl benzoate and glycidyl sorbate; diglycidyl esters such as diglycidyl adipate, diglycidyl terephthalate, and diglycidyl orthophthalate.

Examples of the epoxidized butadiene polymer include epoxidized polybutadiene, epoxidized styrene-butadiene copolymer, and epoxidized hydrogenated styrene-butadiene copolymer.
Examples of the resorcinol epoxy compound include resorcinol diglycidyl ether.

  The epoxy compound (C) may be a copolymer containing a glycidyl group-containing compound as one component. For example, a copolymer of a glycidyl ester of an α, β-unsaturated acid and one or two or more monomers selected from the group consisting of α-olefin, acrylic acid, acrylic acid ester, methacrylic acid, and methacrylic acid ester is exemplified. Can be

  As the epoxy compound (C), an epoxy compound having an epoxy equivalent of 50 to 10,000 g / eq and a weight average molecular weight of 8,000 or less is preferable. When the epoxy equivalent is less than 50 g / eq, the viscosity of the resin composition becomes high because the amount of the epoxy group is too large, and when the epoxy equivalent exceeds 10,000 g / eq, the amount of the epoxy group becomes small. The effects of improving the alkali resistance, heat shock resistance, and hydrolysis resistance of the polybutylene terephthalate resin composition tend to be insufficient. The epoxy equivalent is more preferably 100 to 7000 g / eq, still more preferably 100 to 5000 g / eq, and most preferably 100 to 3000 g / eq. On the other hand, when the weight average molecular weight exceeds 8,000, the compatibility with the polybutylene terephthalate resin tends to decrease, and the mechanical strength of the molded article tends to decrease. The weight average molecular weight is more preferably 7000 or less, and further preferably 6000 or less.

  As the epoxy compound (C), a bisphenol A type epoxy compound or a novolak type epoxy compound obtained from the reaction of bisphenol A or novolak with epichlorohydrin is preferable. Above all, a novolak type epoxy compound is particularly preferable from the viewpoint of improving alkali resistance easily, hydrolysis resistance, heat shock resistance, and surface appearance of a molded article.

  The content of the epoxy compound (C) is 0.3 to 4 parts by mass, preferably 0.4 parts by mass or more, more preferably 0.5 parts by mass or more, based on 100 parts by mass of the polybutylene terephthalate resin (A). And more preferably 0.6 parts by mass or more. Further, it is preferably at most 3.5 parts by mass, more preferably at most 3 parts by mass, further preferably at most 2.5 parts by mass, particularly preferably at most 2.2 parts by mass. If the content of the epoxy compound (C) is less than 0.3 parts by mass, a decrease in alkali resistance and a decrease in hydrolysis resistance are liable to occur, and if the amount exceeds 4 parts by mass, crosslinking proceeds and fluidity during molding is reduced. Easy to get worse.

  Further, the equivalent ratio of the epoxy group of the epoxy compound (C) to the terminal COOH group of the (A) polybutylene terephthalate resin (epoxy group / COOH group) is preferably in the range of 0.2 to 2.7. When the equivalent ratio is less than 0.2, the hydrolysis resistance tends to deteriorate, and when it exceeds 2.7, the moldability tends to be unstable. The epoxy group / COOH group is more preferably at least 0.3 and at most 2.5.

[(D) Reinforcing filler]
The polybutylene terephthalate resin composition of the present invention contains (D) a reinforcing filler in a range of 15 to 80 parts by mass based on 100 parts by mass of the polybutylene terephthalate resin (A). (D) The content of the reinforcing filler is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 40 parts by mass or more, and preferably 75 parts by mass or less, more preferably 70 parts by mass or less.
In the present invention, the reinforced filler refers to a material that improves strength and rigidity by being contained in a resin component, and may be in any form such as fibrous, plate-like, granular, or amorphous.

  (D) When the form of the reinforcing filler is fibrous, it may be either inorganic or organic. For example, glass fiber, carbon fiber, silica / alumina fiber, zirconia fiber, boron fiber, boron nitride fiber, silicon nitride potassium titanate fiber, metal fiber, inorganic fiber such as wollastonite, and organic resin such as fluororesin fiber and aramid fiber. Contains fibers. (D) When the reinforcing filler is fibrous, inorganic fibers are preferred, and glass fibers are particularly preferred. (D) The reinforcing filler may be one kind or a mixture of two kinds.

  (D) When the form of the reinforcing filler is fibrous, its average fiber diameter, average fiber length, and cross-sectional shape are not particularly limited, but the average fiber diameter is preferably selected, for example, in the range of 1 to 100 μm. The length is preferably selected, for example, in the range of 0.1 to 20 mm. The average fiber diameter is more preferably about 1 to 50 μm, and more preferably about 5 to 20 μm. The average fiber length is preferably about 0.12 to 10 mm. When the fiber cross section is a flat shape such as an ellipse, an ellipse, and a cocoon, the flattening ratio (ratio of major axis / minor axis) is preferably 1.4 to 10, more preferably 2 to 6, and more preferably 2. 5 to 5 are more preferred. The use of glass fibers having such an irregular cross section is preferable because dimensional stability such as warpage and anisotropy of shrinkage of a molded product is easily improved.

  In addition to the above-mentioned fibrous reinforcing filler, other reinforcing fillers in the form of plate, granule or amorphous can be contained. The plate-like inorganic filler exhibits a function of reducing anisotropy and warpage, and examples thereof include glass flake, talc, mica, mica, kaolin, and metal foil. Preferred among the plate-like inorganic fillers are glass flakes.

  Other inorganic fillers, granular or amorphous, include ceramic beads, asbestos, clay, zeolite, potassium titanate, barium sulfate, titanium oxide, silicon oxide, aluminum oxide, magnesium hydroxide, and the like.

In order to improve the adhesion of the interface between the reinforcing filler (D) and the resin component, it is preferable to treat the surface of the reinforcing filler (D) with a surface treating agent such as a sizing agent. Examples of the surface treatment agent include epoxy resins, acrylic resins, urethane resins, and functional compounds such as isocyanate compounds, silane compounds, and titanate compounds.
In the present invention, it is preferable to use an epoxy resin for surface treatment. As the epoxy resin, a novolak type epoxy compound such as a phenol novolak type or a cresol novolak type, or a bisphenol A type epoxy resin is preferable. Above all, it is preferable to use a novolak type epoxy compound and a bisphenol type epoxy resin in combination, and it is preferable to use a phenol novolak type epoxy compound and a bisphenol A type epoxy resin in combination in terms of alkali resistance, hydrolysis resistance and mechanical properties. .

As the functional compound, a silane coupling agent such as an aminosilane, an epoxysilane, an allylsilane, or a vinylsilane is preferable, and among them, an aminosilane compound is preferable.
As the aminosilane-based compound, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ- (2-aminoethyl) aminopropyltrimethoxysilane are preferable. γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane are preferred.

In the present invention, the use of a novolak type epoxy resin and a bisphenol type epoxy resin as a so-called sizing agent, and the use of a reinforced filler surface-treated with an aminosilane-based compound as a coupling agent provide alkali resistance and hydrolysis resistance. From the viewpoint of properties, it is particularly preferable. With the surface treatment agent having such a structure, the inorganic functional group of the aminosilane-based compound is highly reactive with the surface of the reinforcing filler (D), and the organic functional group of the aminosilane is highly reactive with the glycidyl group of the epoxy resin. The glycidyl group of the epoxy resin reacts appropriately with the polybutylene terephthalate resin (A), whereby the interfacial adhesion between the reinforcing filler (D) and the epoxy resin is improved. As a result, the alkali resistance, hydrolysis resistance, and mechanical properties of the resin composition of the present invention are easily improved.
Further, without departing from the spirit of the present invention, a urethane resin, an acrylic resin, an antistatic agent, a lubricant, a water repellent and the like can be included in the surface treatment agent, and when these other components are included, It is preferable to use a urethane resin.

(D) The surface treatment of the reinforcing filler can be carried out by a conventionally known method. For example, the surface treatment may be carried out in advance with the above-mentioned surface treating agent, and when the polybutylene terephthalate resin composition of the present invention is prepared. In addition, a surface treatment agent may be added separately from the untreated (D) reinforcing filler to perform surface treatment.
(D) The adhesion amount of the surface treatment agent to the reinforcing filler is preferably 0.01 to 5% by mass, and more preferably 0.05 to 2% by mass. When the content is 0.01% by mass or more, the mechanical strength tends to be more effectively improved, and when the content is 5% by mass or less, a necessary and sufficient effect is obtained, and the production of the resin composition is performed. Tends to be easier, which is preferable.

[(E) Masterbatch containing silicone compound and thermoplastic resin]
The polybutylene terephthalate resin composition of the present invention is blended with (E) a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin. Specifically, it is blended as a master batch in the form of pellets in which a silicone compound is dispersed in a thermoplastic resin.
When the silicone compound is added to the composition in a liquid state, the compound is uniformly finely dispersed in the molded body, so that the probability of the silicone compound being present on the surface of the molded body is reduced, and alkali resistance and hydrolysis resistance are reduced. In addition, since the silicone compound easily bleeds out on the surface, a problem that the surface appearance is deteriorated is likely to occur. In particular, when the molded body is a composite of a metal member and a resin, it becomes more remarkable, and furthermore, since residual stress is easily generated at an interface between the metal member and the resin, heat shock resistance is poor. Becomes On the other hand, when the silicone compound is blended into the composition as a masterbatch as in the present invention, the probability of the presence of the silicone compound on the surface of the molded article is high, so that the hydrolysis resistance and alkali resistance are improved, and the metal and resin are also improved. Even in the case of a composite, since the residual stress is greatly reduced, heat shock resistance can be dramatically improved in addition to hydrolysis resistance and alkali resistance.

In the present invention, a silicone compound having a weight average molecular weight (Mw) of 10,000 to 80,000 is used. If the Mw is less than 10,000, heat shock resistance and alkali resistance are deteriorated. And the surface appearance of the molded product deteriorates.
The Mw of the silicone compound is preferably 20,000 or more, more preferably 30,000 or more, further preferably 40,000 or more, preferably 75,000 or less, more preferably 70,000 or less, and still more preferably 65,000 or less.

  The silicone compound used in the masterbatch of the present invention is an organosilicon compound having a siloxane bond as a skeleton and an organic group or the like directly bonded to silicon. As the organic group directly bonded to silicon, a methyl group, an ethyl group, a phenyl group, a vinyl group, a trifluoropropyl group and a combination thereof are known, but known siloxane compounds having these are particularly limited. Can be used without. Some of the organic groups were substituted with a substituent having an epoxy group, an amino group, a polyether group, a carboxyl group, a mercapto group, an ester group, a chloroalkyl group, an alkyl group having 3 or more carbon atoms, a hydroxyl group, or the like. Siloxane compounds can also be used. The siloxane compounds can be used alone or in combination of two or more.

Siloxane compounds are classified into silicone oils, silicone elastomers, and silicone resins (if necessary, see "Silicone Material Handbook", edited by Dow Corning Toray Co., Ltd., published in August 1993). However, silicone resin and silicone oil are preferred.
Specific examples of silicone oils include dimethyl silicone oil, phenylmethyl silicone oil, alkyl-modified silicone oil, fluorosilicone oil, polyether-modified silicone oil, aliphatic ester-modified silicone oil, amino-modified silicone oil, carboxylic acid-modified silicone oil, Examples include oily silicones such as carbinol-modified silicone oil, epoxy-modified silicone oil, and mercapto-modified silicone oil.

  The thermoplastic resin used in the masterbatch of the present invention is preferably a resin incompatible with the polybutylene terephthalate resin. By using a resin that is incompatible with polybutylene terephthalate as a master batch, the effect of alkali resistance and the like is more enhanced by the presence of the silicone compound at a high concentration in the incompatible resin dispersed in polybutylene terephthalate. It becomes easy to express. Examples of thermoplastic resins that can be used include polyolefin resins, polyamide resins, styrene resins, polyimide resins, polyetherimide resins, polyurethane resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, polymethacrylate resins, and the like. In order to exhibit various effects of the present invention, a polyolefin resin is particularly preferable among the above.

As the polyolefin resin, various polyolefin resins can be used, among which, among others, a homopolymer of ethylene or propylene, a polyethylene resin such as an ethylene copolymer of ethylene and propylene, butene, hexene, octene or vinyl acetate, A polypropylene resin such as a propylene copolymer of propylene and butene, hexene, or octene is preferable. Specific examples of preferred polyethylene resins include high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and ethylene-vinyl acetate copolymer (EVA). Preferred examples of the polypropylene-based resin include polypropylene and propylene-ethylene copolymer.
Among these, a polyethylene resin is preferable, and high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE) are more preferable, and low density polyethylene (LDPE) is particularly preferable.
There are no limitations on the method for producing the polyolefin resin or the polymerization catalyst, and various known production methods such as a solution method, a bulk method, a gas phase, and a high-pressure method, and any of a radical initiator, a Ziegler catalyst, a chromium-based catalyst, and a metallocene-based catalyst. May be used.

  Further, the polyolefin resin may be used alone or as a mixture of two or more.

  As a method for producing a master batch, a conventionally known method can be adopted, and examples thereof include a method of mixing using a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a short-screw or multi-screw extruder, and the like. Among them, a method using a Henschel mixer and a short-screw or multi-screw extruder is preferable, and a method of melt-kneading and pelletizing using a short-screw or multi-screw extruder is particularly preferable. By thus forming a master batch and then melt-kneading it during production, the mechanical properties and slidability of the molded article tend to be better.

  (E) As the masterbatch containing a silicone compound and a thermoplastic resin, a commercially available masterbatch can be used. For example, a masterbatch manufactured by Dow Corning Toray Co., Ltd. and having a trade name of “Silicone Concentrate” can be used. Can also be used.

  (E) The preferable content of the silicone compound in the masterbatch containing the silicone compound and the thermoplastic resin is 10 to 80% by mass, more preferably 20 to 70% by mass, still more preferably 20 to 60% by mass, and particularly preferably. Is from 20 to 50% by mass.

  (E) The content of the masterbatch containing the silicone compound and the thermoplastic resin is 1 to 15 parts by mass, preferably 2 to 12 parts by mass, more preferably 100 parts by mass of the polybutylene terephthalate resin (A). It is 3 to 10 parts by mass. When the content is less than 1 part by mass, it is difficult to sufficiently obtain an effect of improving alkali resistance, and when the content exceeds 15 parts by mass, extrudability and molding processability when the resin composition is produced by melt-kneading are poor, The mechanical properties also decrease.

[(F) Release Agent]
The polybutylene terephthalate resin composition of the present invention preferably contains a release agent. As the release agent, known release agents usually used for polyester resins can be used. Among them, polyolefin compounds and fatty acid ester compounds are preferable in terms of good alkali resistance. Compounds are preferred.

  Examples of the polyolefin-based compound include compounds selected from paraffin wax and polyethylene wax. Among them, those having a weight average molecular weight of 700 to 10000, and more preferably 900 to 8000 are preferable.

  Examples of the fatty acid ester-based compound include saturated or unsaturated monovalent or divalent aliphatic carboxylic acid esters, glycerin fatty acid esters, sorbitan fatty acid esters, and the like, and partially saponified products thereof. Among them, mono- or di-fatty acid esters composed of fatty acids having 11 to 28 carbon atoms, preferably 17 to 21 carbon atoms, and alcohols are preferable.

Examples of the fatty acid include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachinic acid, behenic acid, lignoceric acid, serotinic acid, melisic acid, tetraliacontanic acid, montanic acid, adipic acid, and azelaic acid. Can be Further, the fatty acid may be alicyclic.
Examples of the alcohol include a saturated or unsaturated monohydric or polyhydric alcohol. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monovalent or polyhydric saturated alcohol having 30 or less carbon atoms is preferable, and an aliphatic saturated monohydric alcohol or polyhydric alcohol having 30 carbon atoms or less is more preferable. Here, the term "aliphatic" also includes alicyclic compounds.
Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol and the like. Is mentioned.
The ester compound may contain an aliphatic carboxylic acid and / or an alcohol as impurities, or may be a mixture of a plurality of compounds.

  Specific examples of the fatty acid ester-based compound include glycerin monostearate, glycerin monobehenate, glycerin dibehenate, glycerin-12-hydroxymonostearate, sorbitan monobehenate, pentaerythritol monostearate, and pentaerythritol Stearate, stearyl stearate, ethylene glycol montanate and the like can be mentioned.

  (F) The content of the release agent is preferably from 0.1 to 3 parts by mass, but preferably from 0.2 to 2.5 parts by mass, based on 100 parts by mass of the polybutylene terephthalate resin (A). Is more preferable, and still more preferably 0.5 to 2 parts by mass. When the amount is less than 0.1 part by mass, the surface property tends to decrease due to poor release during melt molding. On the other hand, when the amount exceeds 3 parts by mass, the workability of kneading the resin composition tends to decrease, and Fogging is likely to occur on the surface.

[Stabilizer]
The polybutylene terephthalate resin composition of the present invention preferably contains a stabilizer in that it has an effect of improving thermal stability and preventing deterioration of mechanical strength, transparency and hue. As the stabilizer, a sulfur-based stabilizer and a phenol-based stabilizer are preferable.

  As the sulfur-based stabilizer, any conventionally known sulfur atom-containing compound can be used, and among them, thioethers are preferable. Specifically, for example, didodecylthiodipropionate, ditetradecylthiodipropionate, dioctadecylthiodipropionate, pentaerythritol tetrakis (3-dodecylthiopropionate), thiobis (N-phenyl-β-naphthylamine) ), 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyl dithiocarbamate, nickel isopropyl xanthate, and trilauryl trithiophosphite. Among these, pentaerythritol tetrakis (3-dodecylthiopropionate) is preferable.

  Examples of the phenolic stabilizer include pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) and octadecyl-3- (3,5-di-tert-butyl-4). -Hydroxyphenyl) propionate, thiodiethylenebis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), pentaerythritol tetrakis (3- (3,5-di-neopentyl-4-hydroxyphenyl) ) Propionate) and the like. Among these, pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) ) Propionate is preferred.

  One type of stabilizer may be contained, or two or more types may be contained in any combination and ratio.

  The content of the stabilizer is preferably 0.001 to 2 parts by mass based on 100 parts by mass of the polybutylene terephthalate resin (A). When the content of the stabilizer is less than 0.001 part by mass, it is difficult to expect improvement in thermal stability and compatibility of the resin composition, and a decrease in molecular weight and deterioration in hue during molding are likely to occur. When the amount exceeds the above range, the amount becomes excessive, and the generation of silver and the deterioration of hue tend to occur more easily. The content of the stabilizer is more preferably 0.01 to 1.5 parts by mass, and still more preferably 0.1 to 1 part by mass.

[Flame retardants]
The polybutylene terephthalate resin composition of the present invention can contain a flame retardant for imparting flame retardancy. Examples of the flame retardant include organic halogen compounds, antimony compounds, phosphorus compounds, nitrogen compounds, and other organic and inorganic compounds. Specific examples of the organic halogen compound include brominated polycarbonate, brominated epoxy resin, brominated phenoxy resin, brominated polyphenylene ether resin, brominated polystyrene resin, brominated bisphenol A, pentabromobenzyl polyacrylate, and the like.

  Examples of the antimony compound include antimony trioxide, antimony pentoxide, and sodium antimonate. Examples of the flame retardant of the phosphorus compound include a phosphoric acid ester, polyphosphoric acid, melamine polyphosphate, ammonium polyphosphate, metal phosphinate, and red phosphorus. Examples of the nitrogen-based flame retardant include melamine cyanurate and phosphazene. Examples of organic flame retardants and inorganic flame retardants other than those described above include inorganic compounds such as aluminum hydroxide, magnesium hydroxide, silicon compounds, and boron compounds.

[Other components]
If necessary, the polybutylene terephthalate resin composition of the present invention may contain various conventionally known resin additives as long as the effects of the present invention are not impaired. Various resin additives include antioxidants, ultraviolet absorbers, weather stabilizers, lubricants, coloring agents such as dyes and pigments, catalyst deactivators, antistatic agents, foaming agents, plasticizers, crystal nucleating agents, and crystallization accelerators. Agents and the like.

  The polybutylene terephthalate resin composition of the present invention contains other thermoplastic resins and thermosetting resins other than the above-mentioned essential component resins, as long as the effects of the present invention are not impaired, if necessary. be able to. Examples of other thermoplastic resins include polyamide resins, polycarbonate resins, polyacetal resins, polyphenylene oxide resins, polyphenylene sulfide resins, liquid crystal polyester resins, acrylic resins, and the like.As thermosetting resins, phenol resins, melamine resins, Silicone resin, epoxy resin and the like can be mentioned. These may be one kind or two or more kinds.

  However, other than the resin of the essential component, the content when the other resin is contained is preferably not more than 40 parts by mass, more preferably not more than 30 parts by mass, based on 100 parts by mass of the polybutylene terephthalate resin. Most preferably, it is 20 parts by mass or less, especially 10 parts by mass or less, particularly 5 parts by mass or less, and 2 parts by mass or less.

  The method for producing the polybutylene terephthalate resin composition of the present invention is not limited to a specific method, but (B) 5 to 30 parts by mass of the elastomer (B) with respect to 100 parts by mass of the polybutylene terephthalate resin. Masterbatch 1 containing (C) 0.3 to 4 parts by mass of an epoxy compound, (D) 15 to 80 parts by mass of a reinforcing filler, and (E) a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin. To 15 parts by mass, followed by melting and kneading. The melting and kneading method can be based on a method usually employed for a thermoplastic resin. In addition, as each component of (A) to (E), those described above can be used.

  As a melting and kneading method, for example, after the above-mentioned essential components, and other components to be blended as required, are uniformly mixed with a Henschel mixer, a ribbon blender, a V-type blender, a tumbler, etc., and then mixed uniaxially or multiaxially. A method of melting and kneading with a kneading extruder, a roll, a Banbury mixer, a Labo Plast mill (Brabender), or the like can be used. If necessary, (D) the reinforcing filler is supplied from the side feeder of the kneading extruder, so that breakage of the reinforcing filler can be suppressed and dispersed, which is preferable. The temperature and the kneading time at the time of melting and kneading can be selected depending on the type of the components constituting the resin component, the ratio of the components, the type of the melting and kneading machine, and the like. C. is preferred. When the temperature exceeds 300 ° C., thermal deterioration of each component becomes a problem, and the physical properties of the molded product may be reduced or the appearance may be deteriorated.

The method for producing the desired molded article from the polybutylene terephthalate resin composition of the present invention is not particularly limited, and the molding methods conventionally used for thermoplastic resins, that is, the injection molding method and the insert molding method , A hollow molding method, an extrusion molding method, a compression molding method and the like, and among them, an injection molding method is preferable.
The composition described above in the present invention is suitably used particularly when manufacturing a so-called metal insert molded product in which a metal member and a resin are combined. This is because, when the resin layer made of the composition of the present invention is combined with a metal member, the residual stress at the interface between the metal member and the resin can be reduced, so that the resin layer has excellent heat shock resistance. This is because a molded article can be obtained.
That is, in the present invention, (B) 5 to 30 parts by mass of an elastomer and (C) 0.3 to 4 parts by mass of an epoxy compound, based on 100 parts by mass of (A) polybutylene terephthalate resin, in at least a part of the metal member. , (D) 15 to 80 parts by mass of a reinforcing filler, and (E) a resin composition containing 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin. A metal-resin composite in which resin layers are laminated is also provided.
The metal-resin composite of the present invention is molded by inserting a metal member such as stainless steel or aluminum into a mold and injecting the resin composition containing (A) to (E) therein. be able to.

  Examples of molded articles that can be produced using the polybutylene terephthalate resin composition of the present invention include various storage containers, electric and electronic parts, OA equipment parts, home electric appliance parts, mechanical mechanism parts, building material parts, and other precision equipment parts. , Automotive mechanism parts, sanitary parts, etc. Particularly suitable for food containers, medicine containers, oil and fat product containers, hollow parts for vehicles, motor parts, various sensor parts, connector parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, lamp parts, etc. Can be used. Among them, it is suitable as a molded article for in-vehicle components around an automobile engine, for example, a resin material for in-vehicle components such as various sensors, connectors, distributor components, ignition coil components, and cases and housings thereof.

  In a molded article obtained by molding the polybutylene terephthalate resin composition of the present invention, particularly a composite (metal insert molded article) in which a metal member and a resin are combined, in the alkali resistance test, the insert molded article was 10 mass% NaOH. The time until cracking when immersed in an aqueous solution is preferably 300 hours or more, more preferably 400 hours or more, and still more preferably 500 hours or more. Further, a heat shock resistance test (−40 ° C. × 30 minutes → 130 ° C. ×) Extremely high alkali resistance and resistance such as 280 cycles or more, preferably 300 cycles or more, more preferably 400 cycles or more, and even more preferably 450 cycles or more in the number of cycles of crack generation in a weld line by a heat cycle of 30 minutes. Heat shock can be achieved, especially for automotive It has excellent characteristics with respect to the characteristics required for parts.

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention should not be construed as being limited to the following Description Examples.
The raw material components used in Examples and Comparative Examples are as shown in Table 1 below.

[Examples 1 to 4 and Comparative Examples 1 to 3]
<Production of polybutylene terephthalate resin composition>
Each component other than the glass fibers described in Table 1 was blended in the ratio (all parts by mass) shown in Table 2 below, and this was blended with a 30 mm vent-type twin-screw extruder (manufactured by Nippon Steel Works, Ltd.). Using a screw extruder TEX30α), glass fibers are supplied from a side feeder, melt-kneaded at a barrel temperature of 270 ° C., extruded into strands, and then pelletized by a strand cutter, and pellets of a polybutylene terephthalate resin composition are formed. Obtained.

<Measurement evaluation method>
The measurement and evaluation of various physical properties and performances in Examples and Comparative Examples were performed by the following methods.

(A) Charpy impact strength (unit: kJ / m ² ):
The obtained pellets were dried at 120 ° C. for 6 hours, and then used for measuring Charpy impact strength at a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. using an injection molding machine “NEX80-9E” manufactured by Nissei Plastics Industry Co., Ltd. An ISO test piece was molded, and the notched Charpy impact strength was measured according to ISO179.

(B) Evaluation of hydrolysis resistance: retention of tensile strength (unit:%):
Using an injection molding machine “NEX80-9E” manufactured by Nissei Plastic Industry Co., Ltd., an ISO test piece was prepared at a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C., and a tensile test was performed in accordance with ISO527.
Further, the above-mentioned ISO test piece was subjected to wet heat treatment in saturated steam at a temperature of 121 ° C. at a pressure of 203 kPa for 100 hours. The tensile strength of the ISO test piece before and after the wet heat treatment was measured in accordance with ISO527.
The tensile strength retention (unit:%) was determined from the following equation.
Tensile strength retention (%) = (tensile strength after treatment / tensile strength before treatment) × 100

(C) Heat shock resistance test (unit: cycle)
The obtained pellets were dried at 120 ° C. for 6 hours, and then, using a vertical injection molding machine “TH60 R5VSE” manufactured by Nissei Plastics Co., Ltd., at a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C., a rectangular parallelepiped shape shown in FIG. As shown in FIG. 2, an iron (SUS) insert 1 (length 16 mm × width 33 mm × thickness 3 mm) was charged into the mold cavity 4 with the support pin 2 and inserted (insert iron piece 3). . By insert molding, an insert molded product (length 18 mm × width 35 mm × thickness 5 mm) shown in FIG. 3 was produced. The thickness of the resin part of this insert molded product is 1 mm.
Two weld lines 6 are generated on the support pin traces 5 in the insert molded product. Using this insert molded product, a heat shock resistance test was performed using a thermal shock tester “DTS-30 model” manufactured by Irie Seisakusho.
The conditions of the heat shock resistance test were as follows: a cycle of −40 ° C. for 30 minutes → 130 ° C. for 30 minutes, a heat shock test was performed, and the average number of cycles at which cracks occurred in a total of 10 weld lines of 5 molded products Indicated by value.

(D) Alkali resistance evaluation:
The insert molded product obtained by the same method as in the above (c) heat shock resistance test was immersed in a 10% by mass aqueous NaOH solution at room temperature. After immersion, the presence or absence of cracks was periodically visually checked to determine the time (hr) until cracks occurred. The longer this time, the better the alkali resistance.
(E) Surface appearance evaluation:
Using an injection molding machine "NEX80-9E" manufactured by Nissei Plastic Industry Co., Ltd., a flat plate having a length of 100 mm x a width of 100 mm x a thickness of 3 mm is molded at a cylinder temperature of 250 ° C and a mold temperature of 80 ° C, and the surface appearance is evaluated visually. Sorted as follows.
：: good △: slightly bad ×: extremely bad

(F) Comprehensive evaluation Based on the above results, the following three items were comprehensively evaluated on a three-point scale: 1 for satisfying all, 2 for satisfying 2, and 3 for 1 or less. did.
1) heat shock resistance is 300 cycles or more 2) alkali resistance is 300 hours or more,
3) Surface appearance is ○

The above evaluation results are shown in Table 2 below.

  From the results in Table 2, it can be seen that the polybutylene terephthalate resin compositions of Examples 1 to 4 all achieve a good balance of impact resistance, hydrolysis resistance, heat shock resistance, alkali resistance, and surface appearance. .

  The polybutylene terephthalate resin composition of the present invention can achieve extremely high alkali resistance and heat shock resistance, and is also excellent in impact resistance. It is a very useful material for the production of surrounding automotive parts. Further, it is useful in a wide range of fields such as electric and electronic parts, building material parts, and mechanical parts.

1. Insert iron piece 2. Support pin 3. 3. Insert iron piece inserted in the mold Cavity 5. Support pin mark 6. Weld line

Claims (6)

  (A) 5 to 30 parts by mass of elastomer, (C) 0.3 to 4 parts by mass of epoxy compound, (D) 15 to 80 parts by mass of reinforcing filler, and 100 parts by mass of polybutylene terephthalate resin. E) A polybutylene terephthalate resin composition comprising 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80000 and a thermoplastic resin.   The polybutylene terephthalate resin composition according to claim 1, wherein the epoxy compound (C) is a novolak type epoxy compound.   3. The polybutylene terephthalate resin composition according to claim 1, wherein (E) the thermoplastic resin of the masterbatch is incompatible with the polybutylene terephthalate resin.   4. The polybutylene terephthalate resin composition according to claim 1, wherein (E) the thermoplastic resin of the master batch is a polyolefin resin.   (A) 5 to 30 parts by mass of elastomer, (C) 0.3 to 4 parts by mass of epoxy compound, (D) 15 to 80 parts by mass of reinforcing filler, and 100 parts by mass of polybutylene terephthalate resin. E) Production of a polybutylene terephthalate resin composition characterized by mixing 1 to 15 parts by mass of a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80000 and a thermoplastic resin, followed by melting and kneading. Method.   (B) 5 to 30 parts by mass of an elastomer, (C) 0.3 to 4 parts by mass of an epoxy compound, and (D) a reinforcing filler in at least a part of the metal member, based on 100 parts by mass of the polybutylene terephthalate resin (A). A resin layer comprising a resin composition containing 15 to 80 parts by mass, and (E) a master batch containing a silicone compound having a weight average molecular weight of 10,000 to 80,000 and a thermoplastic resin, and 1 to 15 parts by mass, Metal resin composite.