WO2021153492A1 - Poly(butylene terephthalate) resin composition and molded object - Google Patents

Abstract

A molded object of a poly(butylene terephthalate) resin composition comprising (A) a poly(butylene terephthalate) resin, (B) a polycarbonate resin, and (C) an elastomer, characterized by including the poly(butylene terephthalate) resin (A) and the polycarbonate resin (B) in amounts of 30-75 parts by mass, excluding 30 parts by mass, and of 25-70 parts by mass, excluding 70 parts by mass, respectively, per 100 parts by mass of the sum of (A) and (B) and by having a morphology which includes a phase (a) of the poly(butylene terephthalate) resin (A) and a phase (b) of the polycarbonate resin (B) and in which the elastomer (C) is present in both the phase (a) and the phase (b).

Description

Polybutylene terephthalate resin composition and molded article

The present invention relates to a polybutylene terephthalate resin composition and a molded product. Specifically, the present invention relates to a polybutylene terephthalate resin composition having excellent impact resistance, toughness, flame retardancy, fluidity, surface appearance, and hydrolysis resistance, and a polybutylene terephthalate resin composition thereof. Regarding molded products.

Polybutylene terephthalate resin has excellent heat resistance, moldability, chemical resistance, electrical insulation, and other properties suitable for engineering plastics. Therefore, electrical and electronic parts, automobile parts, other electrical parts, mechanical parts, etc. It is preferably used in.

Since polybutylene terephthalate resin has excellent crystal properties, it has a problem of insufficient toughness represented by impact strength, and in order to solve this problem, research on polymer alloys has been conventionally conducted. Various proposals have also been made for flame-retardant formulations.
For example, Patent Document 1 discloses a flame-retardant polyester resin composition containing a polybutylene terephthalate resin, a polycarbonate resin, a halogen-based flame retardant, a flame retardant aid, and an ester exchange inhibitor as constituents, and Patent Document 2 Discloses a flame-retardant polyester resin composition comprising a polybutylene terephthalate resin, a polycarbonate resin, an elastomer, a flame retardant and a flame retardant aid. Further, Patent Document 3 discloses a polyester resin composition composed of a polyester resin, a polystyrene-based rubber and a flame retardant.

In addition, polybutylene terephthalate resin is easily hydrolyzed by water and water vapor at high temperatures, and is generally chemically and physically used as an industrial material for electrical parts, electronic parts, automobile parts, mechanical parts, etc. In addition to the balance of various properties, it is required to have excellent hydrolysis resistance.
Further, in recent years, the required physical properties in the field of electrical and electronic equipment have become more and more sophisticated, and materials having excellent impact resistance, toughness, flame retardancy, fluidity, surface appearance, hydrolysis resistance, etc. are required. ing. Furthermore, there is a need for impact resistance in a low temperature environment such as −30 ° C.

Japanese Unexamined Patent Publication No. 2007-314664 Japanese Unexamined Patent Publication No. 6-100713 Japanese Unexamined Patent Publication No. 2005-112994

An object (objective) of the present invention is to solve the above-mentioned problems, and to obtain a polybutylene terephthalate resin composition having excellent impact resistance, toughness, flame retardancy, fluidity, surface appearance, and hydrolysis resistance, and a molded product thereof. Is to provide.

As a result of diligent studies to solve the above problems, the present inventor comprises a polybutylene terephthalate resin composition in which a specific amount of a polycarbonate resin is mixed with a polybutylene terephthalate resin and an elastomer is mixed with the polybutylene terephthalate resin. A molded body having a resin phase (a) and a polycarbonate resin phase (b) and having a morphology in which an elastomer is present in both the phases (a) and the phase (b) is impact resistant at low temperature and normal temperature. We have found that the properties, toughness, and flame retardancy are improved, and have reached the present invention.
The present invention relates to the following polybutylene terephthalate resin composition molded article and polybutylene terephthalate resin composition.

1. 1. A molded product composed of a resin composition containing (A) polybutylene terephthalate resin, (B) polycarbonate resin, and (C) elastomer.
Based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is contained in an amount of more than 30 parts by mass and 75 parts by mass or less, and (B) polycarbonate resin is contained in an amount of 25 parts by mass or more and less than 70 parts by mass.
A morphology having (A) a polybutylene terephthalate resin phase (a) and (B) a polycarbonate resin phase (b), and (C) an elastomer present in both the phases (a) and (b). A molded body of a polybutylene terephthalate resin composition characterized by having.
2. The molded product according to 1 above, which has a sea-island structure in which the phase (a) of the polybutylene terephthalate resin (A) forms a matrix phase and the phase (b) of the polycarbonate resin (B) exists in an island shape.
3. 3. (C) The elastomer is a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, and the content thereof is 3 to 30 parts by mass based on a total of 100 parts by mass of (A) and (B). The molded product according to 1 or 2 above.
4. Resin composition The molded product according to any one of 1 to 3 above, wherein the resin composition constituting the molded product further contains a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell as an elastomer.
5. The molded product according to 4 above, wherein the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is present in the polycarbonate resin phase (b).
6. The molding according to 4 or 5 above, wherein the content of the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is 3 to 30 parts by mass based on a total of 100 parts by mass of (A) and (B). body.
7. Resin composition Any of the above 1 to 6 in which the resin composition constituting the molded product further contains the flame retardant (E) in an amount of 3 to 30 parts by mass with respect to a total of 100 parts by mass of (A) and (B). The molded product described in Crab.
8. The molded product according to 7 above, wherein the flame retardant (E) is brominated polycarbonate.
9. Resin composition The resin composition constituting the molded product further contains 0.05 to 10 parts by mass of titanium oxide (F) with respect to 100 parts by mass in total of (A) and (B). The molded product according to any one of.
10. The molded product according to any one of 1 to 9 above, which is a housing.

11. Based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is more than 30 parts by mass and 75 parts by mass or less, (B) polycarbonate resin is 25 parts by mass or more and less than 70 parts by mass, and polysiloxane. A polybutylene terephthalate resin composition containing 3 to 30 parts by mass of a core / shell type elastomer having a rubber core and a styrene-based shell.
12. The resin composition according to 11 above, further containing 3 to 30 parts by mass of a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell with respect to a total of 100 parts by mass of (A) and (B).
13. The resin composition according to 11 or 12 above, further containing 3 to 30 parts by mass of the flame retardant (E) with respect to 100 parts by mass in total of (A) and (B).
14. The resin composition according to 13 above, wherein the flame retardant (E) is brominated polycarbonate.
15. The resin composition according to any one of 11 to 14 above, further containing 0.05 to 10 parts by mass of titanium oxide (F) with respect to 100 parts by mass in total of (A) and (B).

The polybutylene terephthalate resin composition molded product and the polybutylene terephthalate resin composition of the present invention have extremely high impact resistance at extremely low temperatures such as −30 ° C. and impact resistance at room temperature, and are also excellent in toughness. Has excellent fluidity, surface appearance, hydrolysis resistance, and flame retardancy.

FIG. 1 is an SEM photograph of the molded product obtained in Example 1. FIG. 2 is an SEM photograph of the molded product obtained in Example 2. FIG. 3 is an SEM photograph of the molded product obtained in Comparative Example 2. FIG. 4 is a schematic view showing a spiral resin molded product produced in Examples and Comparative Examples.

The contents of the present invention will be described in detail below. In addition, in this specification, "-" is used in the meaning that the numerical values described before and after it are included as the lower limit value and the upper limit value.

The polybutylene terephthalate resin composition molded article of the present invention is a molded article composed of a resin composition containing (A) polybutylene terephthalate resin, (B) polycarbonate resin, and (C) elastomer.
Based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is contained in an amount of more than 30 parts by mass and 75 parts by mass or less, and (B) polycarbonate resin is contained in an amount of 25 parts by mass or more and less than 70 parts by mass.
A morphology having (A) a polybutylene terephthalate resin phase (a) and (B) a polycarbonate resin phase (b), and (C) an elastomer present in both the phases (a) and (b). It is characterized by having.

The polybutylene terephthalate resin composition molded article of the present invention has a sea-island structure, (A) the polybutylene terephthalate resin phase (a) forms a matrix phase, and (B) the polycarbonate resin phase (b) is an island. It has a morphology with a sea-island structure that exists in a shape. When the (C) elastomer is present in both the phases (a) and (b), the impact-resistant reinforcing effect of the (A) polybutylene terephthalate resin and the (B) polycarbonate resin is remarkably exhibited. , Excellent impact resistance can be improved even at extremely low temperatures such as −30 ° C. In order to improve the impact resistance at room temperature and low temperature, the (C) elastomer in the molded product was determined by morphological observation to determine the cross-sectional area in the phase (a) of the (A) polybutylene terephthalate resin and (B) the polycarbonate resin. The area ratio (unit:%) of the cross-sectional area in the phase (a) is preferably 10 to 60%, particularly 20 to 50, with respect to 100% of the total area of the phase (b) with the cross-sectional area. It is preferably%.

The morphology of the polybutylene terephthalate resin composition molded product of the present invention can be measured by observing the cross section of the molded product with an optical microscope, SEM (scanning electron microscope), TEM (transmission electron microscope) or the like.
Specifically, using an SEM, STEM, or TEM analyzer, the core portion of the cross section of the molded product (the portion excluding the surface layer portion having a depth of less than 20 μm, the central portion of the cross section, and the cross section parallel to the flow direction of the resin composition). Is observed at a magnification of 3,000 to 100,000 times under an acceleration voltage of 20 kV.

FIG. 1 shows an example of the morphology of the molded product of the present invention, and is an SEM photograph (magnification: 30,000 times) of the core portion of the molded product obtained in Example 1 of the present invention.
In FIG. 1, it can be seen that the dark gray portion is the phase (a) of the polybutylene terephthalate resin (A) and forms the matrix phase. The gray layer lighter than the phase (a) is the phase (b) of the (B) polycarbonate resin, and exists in an island shape in the sea of the phase (a) of the (A) polybutylene terephthalate resin to form a sea-island structure. You can see that.
In the light gray polycarbonate resin phase (b), the elastomer (C) is present in the form of particles indicated by solid circles in FIG. 1, and is present in the polycarbonate resin phase (b). You can see that there is. Further, it can be seen that the phase indicated by the arrow in FIG. 1 is the phase of the elastomer (C), which is present in the form of particles in the matrix phase of the polybutylene terephthalate resin phase (a).

FIG. 2 shows another example of the morphology of the molded product of the present invention, and is an SEM photograph (magnification: 30,000 times) of the core portion of the molded product obtained in Example 2 of the present invention.
In FIG. 2, it can be seen that the dark gray portion is the phase (a) of the polybutylene terephthalate resin (A) and forms the matrix phase. The gray layer lighter than the phase (a) is the phase (b) of the (B) polycarbonate resin, and exists in an island shape in the sea of the phase (a) of the (A) polybutylene terephthalate resin to form a sea-island structure. You can see that.
In the light gray polycarbonate resin phase (b), the elastomer (C) is present in the form of particles indicated by solid circles in FIG. 2, and is present in the polycarbonate resin phase (b). You can see that there is. Further, in FIG. 2, it can be seen that the phase indicated by the arrow is the phase of the elastomer (C), which is present in the form of particles in the matrix phase of the polybutylene terephthalate resin phase (a).

The molded product of the present invention preferably has a sea-island structure in which the phase (a) of the polybutylene terephthalate resin (A) forms a matrix phase and the phase (b) of the polycarbonate resin (B) is present in an island shape.
Further, in the molded product of the present invention, the (C) elastomer is preferably a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, and the content thereof is 100 in total of (A) and (B). It is preferably 3 to 30 parts by mass on the basis of parts by mass.

Resin Composition The resin composition constituting the molded product preferably further contains a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell as an elastomer, preferably a polysiloxane rubber core and an acrylic shell. The core / shell type elastomer to have is present in the polycarbonate resin phase (b). The content of the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is preferably 3 to 30 parts by mass based on a total of 100 parts by mass of (A) and (B).

When the resin composition molded product (C) contains a core / shell type elastomer having a polysiloxane rubber core and a styrene shell and a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell as the elastomer (C), A core / shell-type elastomer having a polysiloxane rubber core and a styrene-based shell is present in both the (A) polybutylene terephthalate resin phase (a) and the (B) polycarbonate resin phase (b), and the polysiloxane rubber core and the acrylic-based elastomer are present. The core / shell-type elastomer having a shell has the morphology present in the polycarbonate resin phase (b). The core / shell type elastomer having a polysiloxane rubber core and an acrylic shell exists only in the polycarbonate resin phase (b), and (B) the impact resistance reinforcing effect of the polycarbonate resin is further exhibited. Impact resistance at low temperatures can be improved.

Resin composition The resin composition constituting the molded product preferably further contains the flame retardant (E) in an amount of 3 to 30 parts by mass with respect to a total of 100 parts by mass of (A) and (B). (E) is preferably brominated polycarbonate.
Further, the resin composition constituting the resin composition molded product preferably further contains titanium oxide (F), and the content thereof is 0. It is preferably 05 to 10 parts by mass.

The resin composition constituting the resin composition molded product having the above-mentioned morphology is preferably the following polybutylene terephthalate resin composition.

The polybutylene terephthalate resin composition of the present invention is based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is more than 30 parts by mass and 75 parts by mass or less, and (B) polycarbonate resin is 25 parts by mass. It is characterized by containing 3 to 30 parts by mass of a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell as the (C) elastomer.

[(A) Polybutylene terephthalate resin]
In the present invention, the polybutylene terephthalate resin composition contains (A) polybutylene terephthalate resin.
The polybutylene terephthalate resin (A) is a polyester resin having a structure in which a terephthalic acid unit and a 1,4-butanediol unit are ester-bonded, and in addition to the polybutylene terephthalate resin (copolymer), a terephthalic acid unit and 1 Includes polybutylene terephthalate copolymers containing other copolymerization components other than the 4-butanediol unit, and mixtures of homopolymers and the copolymers.

The (A) polybutylene terephthalate resin may contain a dicarboxylic acid unit other than terephthalic acid, and 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) Aromatic dicarboxylic acids such as methane, anthracene dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 4,4'-dicyclohexyldicarboxylic acid, Examples thereof include aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid and dimer acid.

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

As the polybutylene terephthalate resin (A), as described above, a polybutylene terephthalate copolymer obtained by polycondensing terephthalic acid and 1,4-butanediol is preferable, but the carboxylic acid unit is other than the above-mentioned terephthalic acid. A polybutylene terephthalate copolymer containing one or more dicarboxylic acids and / or one or more diols other than the 1,4-butanediol may be used, and the (A) polybutylene terephthalate resin may be used together. In the case of a polybutylene terephthalate resin modified by polymerization, specific preferable copolymers thereof include polyalkylene glycols, particularly polyester ether resin copolymerized with polytetramethylene glycol, and dimer acid copolymerized polybutylene terephthalate. Examples thereof include resins and isophthalic acid copolymer polybutylene terephthalate resins. Above all, it is preferable to use a polyester ether resin copolymerized with polytetramethylene glycol.
In addition, these copolymers have a copolymerization amount of 1 mol% or more and less than 50 mol% in all segments of 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 improved, which is preferable.

The intrinsic viscosity of the polybutylene terephthalate resin (A) is preferably 0.5 to 2 dl / g. If an intrinsic viscosity of less than 0.5 dl / g is used, the obtained polybutylene terephthalate resin material tends to have low mechanical strength. If the value is higher than 2 dl / g, the fluidity of the polybutylene terephthalate resin material may be deteriorated and the moldability may be deteriorated. The intrinsic viscosity is more preferably 0.8 dl / g or more, and more preferably 1.8 dl / g or less.
The intrinsic viscosity shall be measured at 30 ° C. in a 1: 1 (mass ratio) mixed solvent of tetrachloroethane and phenol.

The amount of the terminal carboxyl group of the polybutylene terephthalate resin (A) may be appropriately selected and determined, but is usually 60 eq / ton or less, preferably 50 eq / ton or less, and 30 eq / ton or less. Is even more preferable. If it exceeds 60 eq / ton, the alkali resistance and hydrolysis resistance are lowered, and gas is likely to be generated during melt molding of the resin composition. The lower limit of the amount of the terminal carboxyl group is not particularly determined, but is usually 10 eq / ton in consideration of the productivity of producing the polybutylene terephthalate resin.

The amount of terminal carboxyl groups in the polybutylene terephthalate resin is a value measured by titration using a 0.01 mol / l benzyl alcohol solution of sodium hydroxide in which 0.5 g of the polyalkylene terephthalate resin is dissolved in 25 mL of benzyl alcohol. be. As a method for adjusting the amount of the terminal carboxyl group, a conventionally known arbitrary method such as a method for adjusting the polymerization conditions such as the raw material charging ratio at the time of polymerization, the polymerization temperature, and the depressurization method, and a method for reacting the terminal sequestering agent can be used. Just do it.

In the polybutylene terephthalate resin, a dicarboxylic acid component containing terephthalic acid as a main component or an ester derivative thereof and a diol component containing 1,4-butanediol as a main component are melt-polymerized in a batch or continuous manner. Can be manufactured. Further, 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.
The polybutylene terephthalate resin (A) is obtained by a production method in which a dicarboxylic acid component containing terephthalic acid as a main component and a diol component containing 1,4-butanediol as a main component are continuously melt-polycondensed. Is preferable.

The catalyst used in carrying out the esterification reaction may be a conventionally known catalyst, and examples thereof include titanium compounds, tin compounds, magnesium compounds, and calcium compounds. Of these, particularly suitable ones are titanium compounds. Specific examples of the titanium compound as an esterification catalyst include titanium alcoholates such as tetramethyl titanate, tetraisopropyl titanate and tetrabutyl titanate, and titanium phenolates such as tetraphenyl titanate.

[(B) Polycarbonate resin]
In the present invention, the polybutylene terephthalate resin composition contains (A) a polycarbonate resin together with (A) a polybutylene terephthalate resin.
The polycarbonate resin is a optionally branched thermoplastic polymer or copolymer obtained by reacting a dihydroxy compound or a small amount of a polyhydroxy compound with phosgene or a carbonic acid diester. The method for producing the polycarbonate resin is not particularly limited, and those produced by a conventionally known phosgene method (interfacial polymerization method) or melting method (transesterification method) can be used.

The raw material dihydroxy compound does not substantially contain a bromine atom, and an aromatic dihydroxy compound is preferable. Specifically, 2,2-bis (4-hydroxyphenyl) propane (= bisphenol A), tetramethylbisphenol A, bis (4-hydroxyphenyl) -p-diisopropylbenzene, hydroquinone, resorcinol, 4,4-dihydroxy Examples thereof include diphenyl and the like, preferably bisphenol A. Further, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used.

Among the above-mentioned polycarbonate resins, the aromatic polycarbonate resin derived from 2,2-bis (4-hydroxyphenyl) propane, or 2,2-bis (4-hydroxyphenyl) propane and other aromatic dihydroxys. Aromatic polycarbonate copolymers derived from compounds are preferred. Further, it may be a copolymer mainly composed of an aromatic polycarbonate resin, such as a polymer having a siloxane structure or a copolymer with an oligomer. Furthermore, two or more of the above-mentioned polycarbonate resins may be mixed and used.

To adjust the molecular weight of the polycarbonate resin, a monovalent aromatic hydroxy compound may be used, for example, m- and p-methylphenol, m- and p-propylphenol, p-tert-butylphenol, p-long chain. Examples thereof include alkyl-substituted phenols.

The viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 15,000 or more, more preferably 20,000 or more, still more preferably 23,000 or more, particularly preferably 25,000 or more, and particularly most preferably more than 28,000. preferable. If a resin composition having a viscosity average molecular weight lower than 15,000 is used, the obtained resin composition tends to have low mechanical strength such as impact resistance. The Mv is preferably 60,000 or less, more preferably 40,000 or less, and even more preferably 35,000 or less. If it is higher than 60,000, the fluidity of the resin composition may be deteriorated and the moldability may be deteriorated.

In the present invention, the viscosity average molecular weight (Mv) of the polycarbonate resin is determined by measuring the viscosity of the methylene chloride solution of the polycarbonate resin at 25 ° C. using an Ubbelohde viscometer to obtain the ultimate viscosity ([η]). The value calculated from the following Schnell viscosity formula is shown.
[Η] = 1.23 × 10 ^-4 Mv ^0.83

The method for producing the polycarbonate resin is not particularly limited, and a polycarbonate resin produced by any of the phosgene method (interfacial polymerization method) and the melting method (transesterification method) can be used. Further, a polycarbonate resin produced by the melting method and subjected to post-treatment for adjusting the amount of OH groups at the ends is also preferable.

The content of (B) polycarbonate resin is based on 100 parts by mass in total of (A) polybutylene terephthalate resin and (B) polycarbonate resin, and (B) polycarbonate resin is 25 parts by mass or more and less than 70 parts by mass, preferably. 27 parts by mass or more, more preferably 28 parts by mass or more, further preferably 30 parts by mass or more, preferably 65 parts by mass or less, more preferably 63 parts by mass or less, still more preferably 60 parts by mass or less, particularly 55 parts by mass. Hereinafter, it is preferably 50 parts by mass or less, 48 parts by mass or less, 46 parts by mass or less, and particularly preferably 45 parts by mass or less. (B) When the content of the polycarbonate resin is within the above range, the impact resistance, toughness, chemical resistance, dimensional stability are excellent, the fluidity and moldability are excellent, and the above-mentioned morphology can be easily obtained. Become. If it is less than the above lower limit, the effect of improving the impact resistance and toughness is small, and the dimensional stability is further lowered. Further, if it exceeds the above upper limit value, the fluidity deteriorates and the moldability deteriorates. Further, it tends to be difficult to obtain the morphology described later, and the chemical resistance tends to decrease.
The content of (A) polybutylene terephthalate resin is more than 30 parts by mass and 75 parts by mass or less, preferably 73 parts by mass or less, based on a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. , More preferably 72 parts by mass or less, further preferably 70 parts by mass or less, preferably 35 parts by mass or more, more preferably 37 parts by mass or more, still more preferably 40 parts by mass or more, especially 45 parts by mass or more, 50 parts by mass. Parts or more, 52 parts by mass or more, 54 parts by mass or more are preferable, and 55 parts by mass or more is particularly preferable.

[(C) Elastomer]
In the polybutylene terephthalate resin composition molded article of the present invention, the polybutylene terephthalate resin composition contains (C) an elastomer. Any type of (C) elastomer can be used as long as it can form morphology existing in both the phase (a) of the polybutylene terephthalate resin (A) and the phase (b) of the polycarbonate resin. It is possible. In particular, a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell is preferable. By containing a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, the above-mentioned morphology can be easily formed, impact resistance at room temperature and low temperature, toughness, hydrolysis resistance, and heat retention. The stability can be made excellent. Hereinafter, a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, which is a preferable example of the (C) elastomer, will be described.

The core / shell type elastomer is preferably a graft copolymer obtained by graft-copolymerizing a rubber component with a copolymerizable monomer component, and the method for producing the graft copolymer includes bulk polymerization, solution polymerization, and suspension. Any production method such as turbid polymerization or emulsion polymerization may be used, and the copolymerization method may be a one-step graft or a multi-step graft.
The core / shell type in the present invention does not necessarily mean that the core layer and the shell layer can be clearly distinguished, and the purpose is to broadly include a compound obtained by graft-polymerizing a rubber component around the core portion. Is.

The polysiloxane rubber constituting the core layer of the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell is a polysiloxane rubber (that is, silicone rubber) such as organopolysiloxane, and is an acrylic-silicone composite rubber. It is also preferable.
Acrylic compounds used for acrylic-silicone composite rubber include acrylic acids such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, cyclohexyl acrylate, octyl acrylate, and octyl 2-ethylhexyl acrylate. Esters and methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, and octyl methacrylate can be preferably mentioned, and these can be used alone or in combination of two or more.

In the present invention, the rubber of the core / shell type elastomer preferably has a glass transition temperature of −10 ° C. or lower, more preferably −30 ° C. or lower.

Examples of the styrene-based component constituting the shell layer of the core / shell-type elastomer having a polysiloxane rubber core and a styrene-based shell include styrene-based components such as styrene, α-methylstyrene, p-methylstyrene, alkoxystyrene, and halogenated styrene. It is a polymer of a metric, and is also preferably a copolymer with a vinyl cyanide compound such as acrylonitrile.
As the styrene-based component constituting the shell layer, a styrene-acrylonitrile copolymer is particularly preferable.

In the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, the polysiloxane rubber component is preferably contained in an amount of 40% by mass or more, and more preferably 60% by mass or more.

The content of the core / shell type elastomer is 3 to 30 parts by mass with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. When the content is in such a range, the impact resistance at room temperature and low temperature, as well as the toughness, hydrolysis resistance, and heat retention stability can be made excellent. The content is preferably 5 parts by mass or more, more preferably 7 parts by mass or more, further preferably 9 parts by mass or more, preferably 25 parts by mass or less, and more preferably 20 parts by mass or less.
In order to improve the impact resistance at room temperature and low temperature, the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell has a cross-sectional area in the phase (a) of the (A) polybutylene terephthalate resin according to morphology observation. The area ratio (unit:%) of the cross-sectional area in the phase (a) to 100% of the total area of the cross-sectional area of the phase (b) of the polycarbonate resin (B) is 30 to 70%. Is preferable, and particularly preferably 40 to 60%.

The polybutylene terephthalate resin composition of the present invention further preferably contains a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell.

The polysiloxane rubber constituting the core layer is a polysiloxane rubber (that is, silicone rubber) such as organopolysiloxane, and is preferably an acrylic-silicone composite rubber.
Acrylic compounds used for acrylic-silicone composite rubber include acrylic acids such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, cyclohexyl acrylate, octyl acrylate, and octyl 2-ethylhexyl acrylate. Esters and methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, and octyl methacrylate can be preferably mentioned, and these can be used alone or in combination of two or more.

Examples of the acrylic compound of the acrylic component constituting the shell layer include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, cyclohexyl acrylate, octyl acrylate, octyl 2-ethylhexyl acrylate and the like. Acrylic acid esters of the above, and methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, and octyl methacrylate can be preferably mentioned, and methyl methacrylate is particularly preferable.
The acrylic compound may be used alone or in combination of two or more.

The polysiloxane rubber component preferably contains 40% by mass or more, and more preferably 60% by mass or more.

The content of the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is preferably 3 to 30 parts by mass with respect to 100 parts by mass in total of (A) polybutylene terephthalate resin and (B) polycarbonate resin. .. When the content is in such a range, the above-mentioned morphology can be easily formed, the impact resistance, particularly the impact resistance at a low temperature can be further improved, and the toughness and hydrolysis resistance are excellent. Can be tough. The content is more preferably 5 parts by mass or more, further preferably 7 parts by mass or more, particularly preferably 9 parts by mass or more, more preferably 25 parts by mass or less, still more preferably 20 parts by mass or less, and particularly 15 parts by mass. Below, 10 parts by mass or less is particularly preferable.

[Flame Retardant (E)]
In the present invention, the polybutylene terephthalate resin composition preferably contains a flame retardant (E).
As the flame retardant, known flame retardants for plastics can be used. Specifically, halogen-based flame retardants, phosphorus-based flame retardants (melamine polyphosphate, etc.), nitrogen-based flame retardants (melamine cyanurate, etc.), metals. It is a hydroxide (magnesium hydroxide, etc.).
As the halogen-based flame retardant, a bromine-based flame retardant is more preferable.

As the brominated flame retardant, any conventionally known brominated flame retardant used for thermoplastic resins can be used. Examples of such bromine-based flame retardant include aromatic compounds, and specifically, for example, polybrominated benzyl (meth) acrylate such as pentabromobenzyl polyacrylate, polybromophenylene ether, brominated polystyrene, and the like. Examples thereof include brominated epoxy compounds such as the epoxy oligomer of tetrabromobisphenol A, brominated imide compounds such as N, N'-ethylenebis (tetrabromophthalimide) (EBTPI), and brominated polycarbonate.

Among them, polybromoated benzyl (meth) acrylate such as pentabromobenzyl polyacrylate, brominated epoxy compound such as tetrabromobisphenol A epoxy oligomer, brominated polystyrene, and brominated polycarbonate are preferable from the viewpoint of good thermal stability. Brominated polycarbonate is preferable from the viewpoint of impact resistance and flame retardancy.

As the brominated polycarbonate-based flame retardant, specifically, for example, brominated polycarbonate obtained from brominated bisphenol A, particularly tetrabromobisphenol A, is preferable. Examples of the terminal structure include a phenyl group, a 4-t-butylphenyl group, a 2,4,6-tribromophenyl group, and the like, and in particular, those having a 2,4,6-tribromophenyl group in the terminal group structure. Is preferable.

The average number of repeating units of carbonate in the brominated polycarbonate-based flame retardant may be appropriately selected and determined, but is usually 2 to 30. If the average number of repeating units of carbonate is small, the molecular weight of the (A) polybutylene terephthalate resin may decrease during melting. On the contrary, if it is too large, the melt viscosity of the polycarbonate resin (B) becomes high, causing poor dispersion in the molded product, and the appearance of the molded product, particularly the glossiness, may be deteriorated. Therefore, the average number of repeating units is preferably 3 to 15, particularly preferably 3 to 10.

The molecular weight of the brominated polycarbonate-based flame retardant is arbitrary and may be appropriately selected and determined, but the viscosity average molecular weight is preferably 1000 to 20000, and more preferably 2000 to 10000. The viscosity average molecular weight of the brominated polycarbonate flame retardant can be determined by the same method as in the measurement of the viscosity average molecular weight of the polycarbonate resin (B).

The brominated polycarbonate flame retardant obtained from the above brominated bisphenol A can be obtained, for example, by a usual method of reacting brominated bisphenol with phosgene. Examples of the terminal sequestering agent include aromatic monohydroxy compounds, which may be substituted with halogens or organic groups.

As the polybrominated benzyl (meth) acrylate, a polymer obtained by polymerizing a benzyl (meth) acrylate containing a bromine atom alone, copolymerizing two or more kinds, or copolymerizing with another vinyl-based monomer. The bromine atom is added to the benzene ring, and the number of additions is preferably 1 to 5, particularly 4 to 5 per benzene ring.

Examples of the benzyl acrylate containing the bromine atom include pentabrombenzyl acrylate, tetrabrombenzyl acrylate, tribrombenzyl acrylate, and a mixture thereof. Further, as the benzyl methacrylate containing a bromine atom, a methacrylate corresponding to the above-mentioned acrylate can be mentioned.

Other vinyl-based monomers used for copolymerizing with benzyl (meth) acrylate containing a bromine atom include, for example, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, and benzyl acrylate. Acrylate esters; Methacrylic acid esters such as methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, benzyl methacrylate; unsaturated carboxylic acids such as styrene, acrylonitrile, fumaric acid, maleic acid or anhydrides thereof; vinyl acetate , Vinyl chloride, etc.

Usually, it is preferable to use these in an equimolar amount or less, particularly 0.5 times the molar amount or less, with respect to the benzyl (meth) acrylate containing a bromine atom.

Further, as the vinyl-based monomer, xylenediacrylate, xylenedimethacrylate, tetrabromxylenediacrylate, tetrabromxylene dimethacrylate, butadiene, isoprene, divinylbenzene and the like can also be used, and these usually contain a bromine atom. 0.5 times the molar amount or less can be used with respect to benzyl acrylate or benzyl methacrylate.

As the polybrominated benzyl (meth) acrylate, pentabromobenzyl polyacrylate is preferable from the viewpoint of having a high bromine content and high electrical insulation characteristics (tracking resistance characteristics).

Specific examples of the brominated epoxy compound include a bisphenol A type bromoated epoxy compound represented by a tetrabromobisphenol A epoxy compound.

The molecular weight of the brominated epoxy compound is arbitrary and may be appropriately selected and determined, but the mass average molecular weight (Mw) is preferably 3000 to 100,000, and the higher the molecular weight is preferable, and specifically, Mw. It is preferably 15,000 to 80,000, particularly 18,000 to 78,000 (Mw), further 20,000 to 75,000 (Mw), particularly 22,000 to 70,000, and even within this range, a compound having a high molecular weight is preferable.
The brominated epoxy compound preferably has an epoxy equivalent of 3000 to 40,000 g / eq, particularly preferably 4000 to 35000 g / eq, and particularly preferably 10000 to 30000 g / eq.

In addition, a brominated epoxy oligomer can be used in combination as a brominated epoxy compound-based flame retardant. At this time, for example, by using about 0 to 50% by mass of an oligomer having Mw of 5000 or less, flame retardancy, releasability and fluidity can be appropriately adjusted. The content of the bromine atom in the brominated epoxy compound is arbitrary, but in order to impart sufficient flame retardancy, it is usually 10% by mass or more, and more preferably 20% by mass or more, particularly 30% by mass or more. The upper limit is 60% by mass, preferably 55% by mass or less.

The content of the flame retardant is preferably 3 to 30 parts by mass, more preferably 7 parts by mass or more, still more preferably 7 parts by mass, based on 100 parts by mass of the total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. Is 10 parts by mass or more, more preferably 25 parts by mass or less, and further preferably 20 parts by mass or less. If the content of the flame retardant is too small, the flame retardancy of the resin composition used in the present invention becomes insufficient, and conversely, if the content is too large, problems such as deterioration of mechanical properties and releasability and bleed-out of the flame retardant occur. ..

[Antimony compound]
In the present invention, the polybutylene terephthalate resin composition preferably contains an antimony compound which is a flame retardant auxiliary.
Preferred examples of the antimony compound include antimony trioxide (Sb ₂ O ₃ ), antimony pentoxide (Sb ₂ O ₅ ) and sodium antimonate. Among these, antimony trioxide is preferable from the viewpoint of impact resistance.

The antimony compound is preferably blended as a masterbatch with the (A) polybutylene terephthalate resin. As a result, the antimony compound is likely to be present in the (A) polybutylene terephthalate resin phase, the adverse effect on the (B) polycarbonate resin can be suppressed, and the decrease in impact resistance tends to be suppressed.
The content of the antimony compound in the masterbatch is preferably 20 to 90% by mass. When the amount of the antimony compound is less than 20% by mass, the proportion of the antimony compound in the flame retardant masterbatch is small, and the effect of improving the flame retardancy of the polybutylene terephthalate resin containing the antimony compound is small. On the other hand, when the antimony compound exceeds 90% by mass, the dispersibility of the antimony compound tends to decrease, and when this is blended with the polybutylene terephthalate resin, the flame retardancy of the resin composition becomes unstable, and the flame retardant masterbatch Workability during manufacturing is also significantly reduced, for example, when manufacturing using an extruder, problems such as unstable strands and easy cutting are likely to occur, which is not preferable.
The content of the antimony compound in the masterbatch is preferably 30 to 85% by mass, more preferably 40 to 80% by mass, and further preferably 50 to 75% by mass.

The content of the antimony compound is preferably 1 to 15 parts by mass, more preferably 2 parts by mass or more, still more preferably 2 parts by mass with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. It is .5 parts by mass or more, more preferably 10 parts by mass or less, further preferably 7 parts by mass or less, and particularly preferably 6 parts by mass or less, particularly preferably 5 parts by mass or less. If it is below the above lower limit, the flame retardancy is likely to decrease, and if it exceeds the above upper limit, the crystallization temperature is lowered, the releasability is deteriorated, and the mechanical properties such as impact resistance are lowered.

[Dripping inhibitor]
In the present invention, the polybutylene terephthalate resin composition preferably contains a dropping inhibitor.
As the dripping inhibitor, a fluoropolymer is preferable. As the fluoropolymer, a known polymer having fluorine can be arbitrarily selected and used, and among them, a fluoroolefin resin is preferable.
Examples of the fluoroolefin resin include polymers and copolymers containing a fluoroethylene structure. Specific examples thereof include difluoroethylene resin, tetrafluoroethylene resin, tetrafluoroethylene / hexafluoropropylene copolymer resin and the like. Of these, tetrafluoroethylene resin and the like are preferable. As the fluoroethylene resin, a tetrafluoroethylene resin having a fibril forming ability is preferable.

Further, an aqueous dispersion of a fluoroethylene resin and a fluoroethylene polymer having a multilayer structure formed by polymerizing a vinyl-based monomer can also be used as the fluoropolymer.

The content of the anti-dripping agent is preferably 0.05 to 1 part by mass, more preferably 0.1 part by mass, based on 100 parts by mass of the total of (A) polybutylene terephthalate resin and (B) polycarbonate resin. The above is more preferably 0.12 parts by mass or more, particularly preferably 0.15 parts by mass or more, more preferably 0.6 parts by mass or less, still more preferably 0.45 parts by mass or less, and particularly preferably 0.35 parts by mass. It is less than a part by mass. If the content of the anti-dripping agent is too small, the flame retardancy of the resin composition may be insufficient, and conversely, if the content is too large, the appearance of the molded product of the resin composition may be poor and the mechanical strength may be reduced. It can occur.

[Pigment]
In the present invention, the polybutylene terephthalate resin composition preferably further contains a pigment in order to improve colorability and weather resistance. Examples of the pigment include black pigments such as inorganic pigments (carbon black, for example, acetylene black, lamp black, thermal black, furnace black, channel black, Ketjen black, etc.), white pigments such as titanium oxide, iron red oxide and the like. Examples thereof include red pigments, orange pigments such as molybdate orange, and organic pigments (yellow pigments, orange pigments, red pigments, blue pigments, green pigments, etc.). Of these, carbon black is preferable from the viewpoint of colorability and weather resistance, and titanium oxide is preferably blended from the viewpoint of impact resistance, flame retardancy, and hydrolysis resistance.
By containing titanium oxide, the crystallization of the polybutylene terephthalate resin (A) is appropriately delayed, higher impact resistance can be achieved, and flame retardancy is further improved.

The titanium oxide used is not particularly limited in terms of production method, crystal morphology, average particle size, and the like. There are two methods for producing titanium oxide, the sulfuric acid method and the chlorine method. Titanium oxide produced by the sulfuric acid method tends to have inferior whiteness in the composition to which the titanium oxide is added, so that the object of the present invention is effectively used. To achieve this, those produced by the chlorine method are suitable.

There are two types of titanium oxide crystal morphology, rutile type and anatase type, but the rutile type crystal form is preferable from the viewpoint of light resistance. The average particle size of titanium oxide is preferably 0.01 to 3 μm, more preferably 0.05 to 1 μm, further preferably 0.1 to 0.7 μm, and particularly preferably 0. It is 1 to 0.4 μm. If the average particle size is less than 0.01 μm, the workability during production of the resin composition is poor, and if it exceeds 3 μm, the surface of the molded product is liable to be roughened and the mechanical strength of the molded product is likely to decrease. Two or more types of titanium oxide having different average particle diameters may be mixed and used.

Titanium oxide is preferably surface-treated with an organosiloxane-based surface treatment agent.

The content of the pigment is preferably 0.05 to 10 parts by mass with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. If it is less than 0.05 parts by mass, a desired color may not be obtained, or the effect of improving weather resistance may not be sufficient, and if it exceeds 10 parts by mass, mechanical properties may be deteriorated. The content of the pigment is more preferably 0.05 to 7 parts by mass, still more preferably 0.1 to 5 parts by mass.
The preferable content of titanium oxide is 0.05 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, based on 100 parts by mass of the total of (A) polybutylene terephthalate resin and (B) polycarbonate resin. More preferably, it is 0.1 to 5 parts by mass.

[Stabilizer]
In the present invention, it is preferable that the polybutylene terephthalate resin composition contains a stabilizer because it has an effect of improving thermal stability and preventing deterioration of mechanical strength, transparency and hue. As the stabilizer, one type 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 with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. If 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 of hue during molding are likely to occur, and 2 parts by mass is used. If it exceeds the amount, 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 0.001 to 1.5 parts by mass, still more preferably 0.005 to 1.0 parts by mass.

As the stabilizer, a phosphorus-based stabilizer and a phenol-based stabilizer are preferable. In particular, it is preferable to use both in combination because mechanical properties such as impact resistance tend to be good.

Examples of the phosphorus-based stabilizer include phosphorous acid, phosphoric acid, phosphorous acid ester, phosphoric acid ester and the like, and among them, an organic phosphoric acid ester compound is preferable.

The organic phosphoric acid ester compound has a partial structure in which 1 to 3 alkoxy groups or aryloxy groups are bonded to a phosphorus atom. A substituent may be further bonded to these alkoxy groups and aryloxy groups. Preferably, an organic phosphoric acid ester compound represented by any of the following general formulas (1) to (5) is used. Two or more kinds of organic phosphoric acid ester compounds may be used in combination.

In the general formula (1), R ¹ to R ⁴ independently represent an alkyl group or an aryl group. M represents an alkaline earth metal or zinc.

In the general formula (2), R ⁵ represents an alkyl group or an aryl group, and M represents an alkaline earth metal or zinc.

In the general formula (3), R ⁶ to R ¹¹ independently represent an alkyl group or an aryl group. M'represents a metal atom that becomes a trivalent metal ion.

In the general formula (4), R ¹² to R ¹⁴ independently represent an alkyl group or an aryl group. M'represents a metal atom that becomes a trivalent metal ion, and the two M's may be the same or different.

In the general formula (5), R ¹⁵ represents an alkyl group or an aryl group. n represents an integer of 0 to 2. When n is 0, the three R ^15s may be the same or different, and when n is 1, the two R ^15s may be the same or different.

In the general formulas (1) to (5), R ¹ to R ¹⁵ are usually alkyl groups having 1 to 30 carbon atoms or aryl groups having 6 to 30 carbon atoms. From the viewpoint of heat retention stability, chemical resistance, moisture heat resistance, etc., an alkyl group having 2 to 25 carbon atoms is preferable, and an alkyl group having 6 to 23 carbon atoms is most preferable. Examples of the alkyl group include an octyl group, a 2-ethylhexyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, a dodecyl group, a tridecyl group, an isotridecyl group, a tetradecyl group, a hexadecyl group and an octadecyl group. Further, M of the general formulas (1) and (2) is preferably zinc, and M'of the general formulas (3) and (4) is preferably aluminum.

As a preferable specific example of the organic phosphate compound, the compound of the general formula (1) is a bis (distearyl acid phosphate) zinc salt, the compound of the general formula (2) is a monostearyl acid phosphate zinc salt, and the general formula (3). ) Is an aluminum salt of tris (disteallyl acid phosphate), and the compound of general formula (4) is a salt of one monostearyl acid phosphate and two monostearyl acid phosphate aluminum salts. Examples of the compound (5) include monostearyl acid phosphate and distearyl acid phosphate. These may be used alone or as a mixture.

As an organic phosphate ester compound, it has a very high effect of suppressing ester exchange, has good thermal stability during molding, and has excellent moldability, and it is possible to set the temperature of the measuring part in the injection molding machine higher. Bis (disteallyl acid phosphate) zinc, which is a zinc salt of the organic phosphoric acid ester compound represented by the general formula (1), from the viewpoint of stable molding and excellent hydrolysis resistance and impact resistance. It is preferable to use a salt, a zinc salt of stearyl acid phosphate such as a zinc salt of a monostearyl acid phosphate which is a zinc salt of an organic phosphate compound represented by the general formula (2). Examples of these commercially available products include "JP-518Zn" manufactured by Johoku Chemical Industry Co., Ltd.

The content of the organic phosphoric acid ester compound is preferably 0.001 to 1 part by mass with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. If the content 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 of hue during molding are likely to occur, and if it exceeds 1 part by mass, There is a tendency for the amount to be excessive and the generation of silver and the deterioration of hue to occur more easily. The content of the organic phosphate compound is more preferably 0.01 to 0.8 parts by mass, further preferably 0.05 to 0.7 parts by mass, and particularly preferably 0.1 to 0.5 parts by mass. It is a department.

Examples of the phenolic stabilizer include pentaerythritol tetrakis (3- (3,5-di-t-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) and octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate Is preferable.

The content of the phenolic stabilizer is preferably 0.001 to 1 part by mass with respect to 100 parts by mass in total of the (A) polybutylene terephthalate resin and (B) polycarbonate resin. If the content 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 of hue during molding are likely to occur, and if it exceeds 1 part by mass, There is a tendency for the amount to be excessive and the generation of silver and the deterioration of hue to occur more easily. The content of the phenolic stabilizer is more preferably 0.001 to 0.7 parts by mass, still more preferably 0.005 to 0.5 parts by mass.

[Release agent]
In the present invention, the polybutylene terephthalate resin composition preferably contains a mold release agent. As the release agent, known release agents usually used for polyester resins can be used. Among them, polyolefin-based compounds and fatty acid ester-based compounds are preferable, and polyolefin-based compounds are particularly preferable, because they have good alkali resistance. Compounds are preferred.

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

Examples of fatty acid ester compounds include saturated or unsaturated monovalent or divalent aliphatic carboxylic acid esters, glycerin fatty acid esters, sorbitan fatty acid esters and other fatty acid esters, and partial saponifications thereof. Among them, a mono-fatty acid ester composed of a fatty acid having 11 to 28 carbon atoms, preferably 17 to 21 carbon atoms and an alcohol is preferable.

Examples of fatty acids include palmitic acid, stearic acid, caproic acid, caproic acid, lauric acid, araquinic acid, behenic acid, lignoceric acid, cerotic acid, melissic acid, tetrariacontanic acid, montanic acid, adipic acid, azelaic acid and the like. Be done. Further, the fatty acid may be an alicyclic type.

Examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, monohydric or polyhydric saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the aliphatic term also contains an alicyclic compound.
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. Can be mentioned.

The above ester compound may contain an aliphatic carboxylic acid and / or an alcohol as an impurity, or may be a mixture of a plurality of compounds.

Specific examples of the fatty acid ester compound include glycerin monostearate, glycerin monobehenate, glycerin dibehenate, glycerin-12-hydroxymonostearate, sorbitan monobehenate, pentaerythritol monostearate, and pentaerythritol distea. Examples include rate, stearyl stearate, ethylene glycol montanic acid ester and the like.

The content of the release agent is preferably 0.1 to 3 parts by mass, but 0.2 to 2.5 parts by mass, based on 100 parts by mass of the total of (A) polybutylene terephthalate resin and (B) polycarbonate resin. It is more preferably parts by mass, and even more preferably 0.5 to 2 parts by mass. If it is less than 0.1 part by mass, the surface property tends to be deteriorated due to poor mold release during melt molding, while if it exceeds 3 parts by mass, the kneading workability of the resin composition is likely to be deteriorated, and the molded product is formed. The appearance of the product tends to deteriorate.

[Other ingredients]
In the present invention, the polybutylene terephthalate resin composition may contain other resin additives other than those described above, if necessary, as long as the effects of the present invention are not impaired. Other resin additives include reinforced fillers, anti-dripping agents, UV absorbers, weather-resistant stabilizers, lubricants, catalyst deactivators, antistatic agents, foaming agents, plasticizers, crystal nucleating agents, crystallization accelerators, etc. Can be mentioned.

In the present invention, the polybutylene terephthalate resin composition contains, if necessary, other thermoplastic resin, thermosetting resin, etc. other than the above-mentioned essential component resin as long as the effect of the present invention is not impaired. can do. Examples of other thermoplastic resins include polyamide resins, polyacetal resins, polyphenylene oxide resins, polyphenylene sulfide resins, liquid crystal polyester resins, acrylic resins, and the like, and examples of thermosetting resins include phenol resins, melamine resins, and silicone resins. Examples include epoxy resin. These may be one kind or two or more kinds.

However, when other resins other than the above-mentioned essential component resin are contained, the content is preferably 40 parts by mass or less with respect to 100 parts by mass in total of the polybutylene terephthalate resin and the (B) polycarbonate resin. More preferably, it is 30 parts by mass or less, more preferably 20 parts by mass or less, particularly 10 parts by mass or less, particularly 5 parts by mass or less, and 2 parts by mass or less.

[Manufacturing of polybutylene terephthalate resin composition]
The polybutylene terephthalate resin composition is not limited to a specific method, but is formulated with (A) polybutylene terephthalate resin, (B) polycarbonate resin and (C) elastomer, and if necessary. Other ingredients are mixed, and then melted and kneaded.

As a melting / kneading method, for example, the above-mentioned essential components and other components to be blended as necessary are uniformly mixed with a Henschel mixer, a ribbon blender, a V-type blender, a tumbler, or the like, and then uniaxial or multiaxial. Examples thereof include a method of melting and kneading with a kneading extruder, a roll, a Banbury mixer, a lab plast mill (lavender), or the like. From the viewpoint of easily forming the morphological structure of the present invention, it is preferable to melt and knead with a twin-screw extruder. The temperature at the time of melting and kneading is preferably in the range of 200 to 300 ° C., and more preferably in the range of 220 to 280 ° C. from the viewpoint of easily forming the morphological structure of the present invention.

[Molded product]
As a method for producing a molded product using the above-mentioned polybutylene terephthalate resin composition, any molding method generally used for the polybutylene terephthalate resin composition can be arbitrarily adopted, and an injection molding method, an ultra-high-speed injection molding method, or injection can be used. Compression molding method, two-color molding method, hollow molding method such as gas assist, molding method using heat insulating mold, molding method using rapid heating mold, insert molding, IMC (in-mold coating molding) molding method, extrusion Examples thereof include a molding method and a sheet molding method, but an injection molding method is particularly preferable.

The obtained polybutylene terephthalate resin composition molded body has (A) a polybutylene terephthalate resin phase (a) and (B) a polycarbonate resin phase (b) as described above, and (C) an elastomer is a phase. It has a sea-island structure existing in both the phases (a) and the phase (b), the phase (a) of the polybutylene terephthalate resin (A) forms a matrix phase, and the phase (b) of the polycarbonate resin (B). Has a morphology with a sea-island structure that exists in an island shape.

Further, the resin composition molded product preferably has (C) a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, so that both phases (a) and (b) can be formed. Existence, the effect of reinforcing the impact resistance of (A) polybutylene terephthalate resin and (B) polycarbonate resin is remarkably exhibited, and excellent impact resistance can be improved even at an extremely low temperature such as −30 ° C. ..
Further, when a core / shell type elastomer having a polycarbonate rubber core and an acrylic shell is contained, the core / shell type elastomer having a polysiloxane rubber core and a styrene shell is (A) a polybutylene terephthalate resin phase (a). The core / shell elastomer present in both the (B) polycarbonate resin phase (b) and having the polysiloxane rubber core and the acrylic shell is present only in the polycarbonate resin phase (b), so that the (B) polycarbonate By further exhibiting the effect of reinforcing the impact resistance of the resin, the impact resistance at low temperatures can be further improved.

As described above, in FIG. 1, the dark gray portion is the phase (a) of the (A) polybutylene terephthalate resin, the phase (a) forms the matrix phase, and the gray layer lighter than the phase (a) is (B). ) It can be seen that it is the phase (b) of the polycarbonate resin and exists in an island shape in the sea of the phase (a) of the polybutylene terephthalate resin (A) to form a sea-island structure.
In the light gray polycarbonate resin phase (b), the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell is present in the form of particles indicated by solid circles in FIG. It can be seen that it is present in the polycarbonate resin phase (b). Further, in FIG. 1, the phases indicated by the arrows are the phase of the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, and are present in the form of particles in the matrix phase of the polybutylene terephthalate resin phase (a). You can see that.
Further, in FIG. 1, it can be seen that the broken line circle is a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell, and is present only in the polycarbonate resin phase (b).

Further, as described above, in FIG. 2, the dark gray portion is the phase (a) of the (A) polybutylene terephthalate resin, the phase (a) forms the matrix phase, and the gray layer lighter than the phase (a) is formed. It is the phase (b) of the polycarbonate resin (B), and exists in an island shape in the sea of the phase (a) of the polybutylene terephthalate resin (A) to form a sea-island structure.
Then, in the light gray polycarbonate resin phase (b), the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell exists in the form of particles indicated by solid circles in FIG. It can be seen that it is present in the polycarbonate resin phase (b). Further, in FIG. 2, the phases indicated by the arrows are the phase of the core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, and are present in the form of particles in the matrix phase of the polybutylene terephthalate resin phase (a). You can see that.

FIG. 3 is an SEM photograph of the core portion of the molded product obtained in Comparative Example 2.
In FIG. 3, it can be seen that the dark gray portion is the phase (a) of the polybutylene terephthalate resin (A) and forms the matrix phase. The gray layer lighter than the phase (a) is the phase (b) of the (B) polycarbonate resin, and exists in an island shape in the sea of the phase (a) of the (A) polybutylene terephthalate resin to form a sea-island structure. ing.
In the light gray polycarbonate resin phase (b), the black phase indicated by the broken circle in FIG. 3 is a core / shell type elastomer having a polysiloxane-acrylate-based core and an acrylate-based shell, and is a polycarbonate resin phase. It can be seen that it exists only in (b) and does not exist in the form of particles in the matrix phase of the polybutylene terephthalate resin phase (a).

The polybutylene terephthalate resin composition molded product of the present invention is excellent in impact resistance, toughness, flame retardancy, fluidity, surface appearance, and hydrolysis resistance at low temperature and normal temperature. Examples of the molded product here include an injection molded product, an extrusion molded product, a sheet, a pipe, and various films. The shape, size, thickness, etc. of these molded bodies are arbitrary.

The molded body includes electric / electronic parts, automobile parts and other electrical parts, mechanical parts, cooking utensils, and other household appliances, for example, a charger connector for an electric vehicle, a holder for a battery capacitor, a housing for a battery capacitor, or electricity. It can be suitably used for housings for automobile charging stands, housings for electronic and electrical equipment parts, connectors, relays, switches, sensors, actuators, terminal switches, rice cooker-related parts, grill cooking equipment parts, and the like. In particular, it can be suitably used as a charger connector for an electric vehicle, a holder for a battery capacitor, a housing for a battery capacitor, or a housing for a charging stand for an electric vehicle, especially when these are used in a low temperature environment such as -30 ° C. Suitable.

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not 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 7, Comparative Examples 1 to 4]
<Manufacturing of polybutylene terephthalate resin composition>
Each component shown in Table 1 is blended at the ratio shown in Table 2 below (all by mass), and this is blended in a 30 mm bent type twin-screw extruder (manufactured by Japan Steel Works, Ltd., twin-screw extruder TEX30α). ) Was melt-kneaded at a barrel temperature of 270 ° C., extruded into strands, and then pelletized with a strand cutter to obtain pellets of a polybutylene terephthalate resin composition.
Next, the obtained pellets of the polybutylene terephthalate resin composition were dried at 120 ° C. for 8 hours using a hot air dryer, and a flat plate having a length of 100 mm, a width of 100 mm, and a thickness of 3 mm was formed by an injection molding machine (Nissei Resin Industry Co., Ltd.). Using a film gate mold, the holding pressure value is a cylinder temperature of 260 ° C., a mold temperature of 80 ° C., a cooling time of 20 seconds, a filling time of 1.0 second, and 50% of the injection peak pressure. The injection molding was performed under the conditions of.

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

[Morphology observation]
Using "UC7" manufactured by Leica from a cross section parallel to the flow direction at the time of molding, including a center point having a thickness of 1.5 mm at a position of 50 mm in length and 50 mm in width of the flat plate obtained above. A block-shaped sample having an observation surface of 500 μm in length × 500 μm in width and a thickness of about 1 cm was cut out with a diamond knife. The observation surface of the obtained sample was stained with ruthenium tetroxide in a gas phase at room temperature for 120 minutes, and then using a scanning electron microscope (“SU8020” manufactured by Hitachi High-Tech), an acceleration voltage of 1 kV, a signal LA100 (U), An SEM image with a magnification of 30,000 times was acquired under the conditions of an emission current of 10 μA and a probe current of Normal.
From the obtained SEM image, observe the morphology of (A) polybutylene terephthalate resin phase (a), (B) polycarbonate resin phase (b), and (C) elastomer, and determine in which phase each elastomer is present. confirmed.

Further, an SEM image having a magnification of 10000 times was acquired under the conditions of an acceleration voltage of 1 kV, a signal LA100 (U), an elastomer current of 10 μA, and a probe current: Normal. The elastomer inside and the elastomer in the (B) polycarbonate resin phase (b) were binarized and distinguished. For image processing, "Image Pro Plus" manufactured by Nippon Roper Co., Ltd. was used.
The total cross-sectional area Sa1 of the elastomer C1 in the (A) polybutylene terephthalate resin phase (a) and the total cross-sectional area Sa2 of the elastomer C1 in the (B) polycarbonate resin phase (b) were obtained, and the total of Sa1 and Sa2 was obtained. The area ratio (unit:%) "Sa" of Sa1 to 100% of the area was calculated. Further, a value obtained by dividing Sa by the mass part "W" of the polybutylene terephthalate resin was calculated. Sa / W is preferably 0.75 to 1.30, more preferably 0.75 to 1.20, and even more preferably 0.75 to 1.10. Within the above range, both notched Charpy at room temperature and low temperature are improved.
Further, the total cross-sectional area Sb1 of all the elastomers in the (A) polybutylene terephthalate resin phase (a) and the total cross-sectional area Sb2 of all the elastomers in the (B) polycarbonate resin phase (b) were obtained, and Sb1 and Sb2 were obtained. The area ratio (unit:%) of Sb1 to 100% of the total area of Sb1 was calculated. Further, a value obtained by dividing Sb by the mass part "W" of the polybutylene terephthalate resin was calculated. Sb / W is preferably 0.35 to 0.90. Within the above range, both notched Charpy at room temperature and low temperature are improved.
Sa, Sa / W, Sb and Sb / W are listed in Table 2.

[Impact resistance Charpy impact strength with notch (unit: kJ / m ² )]
The obtained pellets are dried at 120 ° C. for 6 hours, and then used for measuring the impact strength of Charpy under the conditions of a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. using an injection molding machine "NEX80-9E" manufactured by Nissei Resin Industry Co., Ltd. The ISO test piece was molded, and the notched Charpy impact strength at room temperature (23 ° C.) and low temperature (-30 ° C.) was measured according to ISO179.

[Combustibility UL94 (1.5 mmt)]
The obtained pellets are subjected to a combustion test piece having a thickness of 12.5 mm × 125 mm × 1.5 mm in an injection molding machine (“NEX80” manufactured by Nissei Resin Industry Co., Ltd.) under the conditions of a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. Was injection molded.
The flame retardancy was evaluated as follows.
Combustibility was tested using the five combustion test pieces (thickness 1.5 mm) obtained above according to the method of Subject 94 (UL94) of Underwriters Laboratories, and V-0, V-1, Classified as V-2 and non-conforming.
The average number of seconds of combustion time t1 (seconds) after the first 10 seconds of contact with the five combustion test pieces was determined.

[Flow characteristics Spiral flow length (unit: mm)]
As an evaluation of fluidity, the spiral flow flow length of the resin composition was measured.
Using the obtained pellets, using an injection molding machine (“α100iA type” manufactured by FANUC), cylinder temperature 250 ° C., mold temperature controller set temperature 80 ° C., injection pressure 168 MPa, injection time 2 sec, cooling 7 sec, A resin was injected and molded under the condition of a suckback of 1 mm to obtain a spiral molded product as shown in FIG. 4, and the length of the obtained molded product was measured as a spiral flow length (mm).
The shape of the evaluated spiral molded product is 105 mm in length, 90 mm in width, 1.0 mm in wall thickness in cross section, and 5 mm in width (gate portion is 1.0 mm in wall thickness and 1.5 mm in width), and is a long resin molded product. It is a spiral shape.
The larger the value of this spiral flow length, the better the fluidity.

[comprehensive evaluation]
Based on the above results, a comprehensive evaluation was performed according to the following criteria A to D.
Comprehensive evaluation A:
Charpy impact strength at normal temperature 50 kJ / ^{m 2} or more at -30 ° C. at 15 kJ / ^{m 2} or more, UL94 is V-0, and t1 combustion average time is 3 seconds or less, the spiral flow length is overall evaluation than 100 mm B:
Charpy impact strength at normal temperature 50 kJ / ^{m 2} or more at -30 ° C. at 15 kJ / ^{m 2} or more, UL94 is V-0, and t1 combustion average time is 3 seconds or less, a spiral flow length of less than 100mm Overall Rating C:
Charpy impact strength at room temperature during 50 kJ / ^{m 2} or more -30 ° C. at 15 kJ / ^{m 2} or more, UL94 is V-0, and t1 combustion Average time 3 seconds super Overall Rating D:
Sharpy impact strength is 50 kJ / m ² or more at room temperature and less than 15 kJ / m ² at -30 ° C, UL94 is V-0, and t1 combustion average time is over 3 seconds. Comprehensive evaluation E:
Charpy impact strength is shown in Table 2 below -30 ° C. at 15 kJ / ^{m 2} less results in less than normal temperature during 50 kJ / ^{m 2.}

The polybutylene terephthalate resin composition molded product and the resin composition of the present invention are excellent in impact resistance, toughness, fluidity, surface appearance, hydrolysis resistance, and flame retardancy, and therefore, various electrical and electronic equipment parts, automobiles, etc. For home appliances such as parts, other electrical parts, mechanical parts, cookware, etc., especially for electric vehicle charger connectors, battery capacitor holders, battery capacitor housings or electric vehicle charging stand housings. These are also suitable when used in a low temperature environment such as −30 ° C., and some of them have very high industrial utility.

Claims (15)

1. A molded product composed of a resin composition containing (A) polybutylene terephthalate resin, (B) polycarbonate resin, and (C) elastomer.
   Based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is contained in an amount of more than 30 parts by mass and 75 parts by mass or less, and (B) polycarbonate resin is contained in an amount of 25 parts by mass or more and less than 70 parts by mass.
   A morphology having (A) a polybutylene terephthalate resin phase (a) and (B) a polycarbonate resin phase (b), and (C) an elastomer present in both the phases (a) and (b). A molded body of a polybutylene terephthalate resin composition characterized by having.
2. The molded product according to claim 1, wherein the phase (a) of the polybutylene terephthalate resin (A) forms a matrix phase, and the phase (b) of the polycarbonate resin (B) has an island-like structure.
3. The elastomer (C) is a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell, and the content of (C) is 3 to 30 based on a total of 100 parts by mass of (A) and (B). The molded product according to claim 1 or 2, which is a part by mass.
4. The molded product according to any one of claims 1 to 3, wherein the resin composition constituting the resin composition molded product further contains a core / shell type elastomer having a polysiloxane rubber core and an acrylic shell.
5. The molded product according to claim 4, wherein the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is present in the polycarbonate resin phase (b).
6. The fourth or fifth claim, wherein the content of the core / shell type elastomer having a polysiloxane rubber core and an acrylic shell is 3 to 30 parts by mass based on a total of 100 parts by mass of (A) and (B). Molded body.
7. Resin composition The resin composition constituting the molded product further contains the flame retardant (E) in an amount of 3 to 30 parts by mass based on 100 parts by mass in total of (A) and (B). The molded product according to any one.
8. The molded product according to claim 7, wherein the flame retardant (E) is brominated polycarbonate.
9. Resin composition The resin composition constituting the molded product further contains 0.05 to 10 parts by mass of titanium oxide (F) with respect to 100 parts by mass in total of (A) and (B). The molded product according to any one of 8.
10. The molded product according to any one of claims 1 to 9, which is a housing.
11. Based on a total of 100 parts by mass of (A) and (B), (A) polybutylene terephthalate resin is more than 30 parts by mass and 75 parts by mass or less, (B) polycarbonate resin is 25 parts by mass or more and less than 70 parts by mass, and (C). ) A polybutylene terephthalate resin composition containing 3 to 30 parts by mass of a core / shell type elastomer having a polysiloxane rubber core and a styrene-based shell as an elastomer.
12. The 11. Resin composition.
13. The resin composition according to claim 11 or 12, further containing 3 to 30 parts by mass of the flame retardant (E) with respect to a total of 100 parts by mass of (A) and (B).
14. The resin composition according to claim 13, wherein the flame retardant (E) is brominated polycarbonate.
15. The resin composition according to any one of claims 11 to 14, further containing 0.05 to 10 parts by mass of titanium oxide (F) with respect to 100 parts by mass in total of (A) and (B).

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