JP2019043991A - Polybutylene terephthalate resin composition, molding and complex - Google Patents

Abstract

To provide a polybutylene terephthalate resin composition that has excellent alkali solution resistance and hydrolysis resistance, and has excellent flowability, and a molding and a complex including the same.SOLUTION: A polybutylene terephthalate resin composition contains (A) a polybutylene terephthalate resin of 100 pts.mass, (B) an epoxy resin in such an amount that an epoxy group content is 0.5-1.5 when a terminal carboxyl group content of the polybutylene terephthalate resin (A) is 1, (C) a silicone-based compound of 0.5-5 pts.mass, and (D) a phosphorous compound of 0.05-0.5 pts.mass.SELECTED DRAWING: None

Description

  The present invention relates to a polybutylene terephthalate resin composition, and a molded article and a composite using the same.

Polybutylene terephthalate resin (PBT resin) is excellent in various properties such as mechanical properties, electrical properties, heat resistance, chemical resistance and solvent resistance. It is widely used in various applications. However, when a molded product obtained by molding PBT resin is exposed to an alkaline solution for a long time, the strength may be reduced, or a so-called stress crack may be generated due to external stress or residual stress due to molding processing. There are times when Therefore, when using the molded article using PBT resin as components which contact alkaline solutions, such as a detergent and a snow melting agent, improving alkali-proof solution resistance is calculated | required. Furthermore, when using a molded article in a high temperature and humidity environment, it is also required to improve the hydrolysis resistance.
As a technique for improving the alkali solution resistance of the PBT resin, there are a technique of adding an epoxy compound to the PBT resin and a technique of adding an epoxy resin and a silicone compound (Patent Documents 1 and 2).
JP, 2010-144154, A International Publication No. 2000/078867 pamphlet

  However, when an epoxy resin is added to the PBT resin, the viscosity may be increased and the fluidity may be reduced. In such a case, the formability is unfavorably reduced. Moreover, according to the research of the present inventor, the resin composition in which the epoxy resin and the silicone compound are added to the PBT resin is particularly deteriorated in fluidity when it is retained in a molten state for a long time in a molten state at injection molding. It turned out that the formability is further lowered and it is not preferable.

  An object of the present invention is to provide a polybutylene terephthalate resin composition excellent in alkali solution resistance and hydrolysis resistance and excellent in flowability, and a molded article and a composite using the same.

One aspect of the present invention is as follows.
[1] 100 mass parts of (A) polybutylene terephthalate resin, (B) the amount of epoxy groups when the amount of terminal carboxyl groups of (A) polybutylene terephthalate resin is 1 is 0.5 to 1.5 The polybutylene-terephthalate-resin composition containing an epoxy resin, 0.5-5 mass parts of (C) silicone type compounds, and 0.05-0.5 mass parts of (D) phosphorus type compounds.
[2] (D) The phosphorus compound is one or two selected from an alkali metal phosphate, an alkaline earth metal phosphate, an organic phosphate compound, an organic phosphite compound, an organic phosphonate compound, and an organic phosphonite compound The polybutylene terephthalate resin composition as described in the above-mentioned [1], containing a species or more.
[3] The above [1] or [1], wherein the (D) phosphorus compound contains one or more selected from an alkali metal phosphate, an alkaline earth metal phosphate and an organic phosphite compound. The polybutylene terephthalate resin composition as described in 2].
[4] The polybutylene terephthalate resin composition according to any one of the above [1] to [3], wherein the (D) phosphorus compound contains an alkali metal phosphate and / or an alkaline earth metal phosphate. .
[5] The polybutylene terephthalate resin composition according to any one of the above [1] to [4], wherein the (D) phosphorus-based compound contains sodium dihydrogen phosphate.
[6] The polybutylene terephthalate resin composition according to any one of the above [1] to [5], wherein the (C) silicone compound contains a silicone oil.
[7] The polybutylene terephthalate resin composition according to any one of the above [1] to [6], which is for a molded article having a thin-walled part having a thickness of 1 mm or less at least partially.
[8] The polybutylene terephthalate resin composition according to any one of the above [4] to [7], which is for a molded article having a silicone adhesive layer formed on at least one surface.
[9] A molded article molded using the polybutylene terephthalate resin composition according to any one of the above [1] to [8].
[10] The molded article according to the above [9], wherein the thickness of at least a part of the portion containing the polybutylene terephthalate resin composition is 1 mm or less.
[11] A molded article molded using the polybutylene terephthalate resin composition according to any one of the above [4] to [8], and a silicone adhesive layer formed on at least one surface of the molded article And a complex.

  According to the present invention, it is possible to provide a polybutylene terephthalate resin composition excellent in alkali solution resistance and hydrolysis resistance and excellent in flowability, and a molded article and a composite using the same.

  Hereinafter, an embodiment of the present invention will be described in detail. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications as long as the effects of the present invention are not impaired.

[Polybutylene terephthalate resin composition]
The present inventor can not only suppress the increase in viscosity of the polybutylene terephthalate resin composition due to the addition of the epoxy resin by adding the phosphorus compound to the polybutylene terephthalate resin composition containing the epoxy resin and the silicone compound. Rather, it has been found that the flowability can be further enhanced, and the flowability can be prevented from being excessively lowered even when being retained in the cylinder in the molten state for a long time in the injection molding or the like. And, it is found that a polybutylene terephthalate resin composition excellent in alkali solution resistance and hydrolysis resistance and excellent in fluidity can be obtained by setting the content of the epoxy resin and the phosphorus compound in a predetermined range. Thus, the invention according to the present embodiment has been completed.

  The polybutylene terephthalate resin composition (hereinafter, also referred to as “PBT resin composition”) according to the present embodiment includes (A) polybutylene terephthalate resin, (B) epoxy resin, (C) silicone compound, and D) Contains a phosphorus-based compound. Hereinafter, each component will be described by way of examples.

((A) Polybutylene terephthalate resin)
As polybutylene terephthalate resin (hereinafter, also simply referred to as "PBT resin"), butylene terephthalate is a main component (for example, 50% by mass to 100% by mass, preferably 60% by mass to 100% by mass, more preferably 75% Homopolyester (polybutylene terephthalate) or copolyester (butylene terephthalate-based copolymer or polybutylene terephthalate copolyester) or the like.

  Examples of copolymerizable monomers in copolyesters (hereinafter, also referred to as "copolymerizable monomers") include dicarboxylic acids other than terephthalic acid, diols other than 1,4-butanediol, oxycarboxylic acids, lactones, and the like. . The copolymerizable monomers can be used alone or in combination of two or more.

Examples of dicarboxylic acids include aliphatic dicarboxylic acids (eg, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, hexadecanedicarboxylic acid, dimer acid, etc. _{C 4-40} dicarboxylic acids, preferably _{C 4-14} dicarboxylic acids), alicyclic dicarboxylic acids (e.g., hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, _{C 8-12} dicarboxylic such himic acid Acids, aromatic dicarboxylic acids other than terephthalic acid (eg, phthalic acid, isophthalic acid; naphthalene dicarboxylic acids such as 2,6-naphthalene dicarboxylic acid; 4,4'-diphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid 4,4'-diphenylmethane dical Phosphate, 4,4'-diphenyl ketone C _8-16 diphenyl dicarboxylic acid such as dicarboxylic acids), or reactive derivatives thereof [for example, lower alkyl esters of phthalic acid such as (dimethyl phthalate, dimethyl isophthalate (DMI) Or a C _1-4 alkyl ester of isophthalic acid, etc., an acid chloride, an ester formable derivative such as an acid anhydride, etc., and the like. Furthermore, polycarboxylic acids such as trimellitic acid and pyromellitic acid may be used in combination, as necessary.

Examples of diols include aliphatic alkylene glycols other than 1,4-butanediol (eg, ethylene glycol, trimethylene glycol, propylene glycol, neopentyl glycol, hexanediol, octanediol, decanediol, etc.) Linear C _2-12 aliphatic glycol, preferably linear or branched C _2-10 aliphatic glycol), (poly) oxyalkylene glycol (glycol having a plurality of oxy C _2-4 alkylene units, for example, Diethylene glycol, dipropylene glycol, ditetramethylene glycol, triethylene glycol, tripropylene glycol, polytetramethylene glycol, etc., alicyclic diol (eg, 1,4-cyclohexanediol, 1,4-cyclohexene) Nji methanol, hydrogenated bisphenol A, etc.), aromatic diol (e.g., hydroquinone, resorcinol, C _6-14 aromatic diols such as naphthalene diol; biphenol; bisphenols; xylylene glycol and the like) and the like. Furthermore, if necessary, polyols such as glycerin, trimethylolpropane, trimethylolethane, pentaerythritol and the like may be used in combination.

Examples of the bisphenols include bis (4-hydroxyphenyl) methane (bisphenol F), 1,1-bis (4-hydroxyphenyl) ethane (bisphenol AD), 1,1-bis (4-hydroxyphenyl) propane, 2 , 2-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2- Bis (hydroxyaryl) C ₁ such as bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane and the like _-6 alkanes; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydrate Bis (hydroxyaryl) C _4-10 cycloalkanes such as yloxyphenyl) cyclohexane; 4,4'-dihydroxydiphenyl ether; 4,4'-dihydroxydiphenyl sulfone; 4,4'-dihydroxydiphenyl sulfide; 4,4'-dihydroxy Diphenyl ketone, and alkylene oxide adducts of these can be exemplified. As the alkylene oxide adduct, a C _2-3 alkylene oxide adduct of a bisphenol (eg, bisphenol A, bisphenol AD, bisphenol F, etc.), for example, 2,2-bis- [4- (2-hydroxyethoxy) phenyl Propane, diethoxylated bisphenol A (EBPA), 2,2-bis- [4- (2-hydroxypropoxy) phenyl] propane, dipropoxylated bisphenol A and the like can be mentioned. In the alkylene oxide adduct, the addition mole number of the alkylene oxide (C _2-3 alkylene oxide such as ethylene oxide and propylene oxide) is about 1 to 10 moles, preferably about 1 to 5 moles, with respect to each hydroxyl group.

The oxycarboxylic acids include, for example, oxybenzoic acids, oxynaphthoic acids, hydroxyphenylacetic acids, glycolic acids, oxycarboxylic acids such as oxycaproic acid, or derivatives thereof. The lactones include C _3-12 lactones such as propiolactone, butyrolactone, valerolactone, caprolactone (eg, ε-caprolactone etc.), and the like.

Preferred copolymerizable monomers include diols or dicarboxylic acids. As the diols, C _2-6 alkylene glycol (a linear or branched alkylene glycol such as ethylene glycol, trimethylene glycol, propylene glycol, hexanediol, etc.), an oxyalkylene unit having a repeating number of about 2 to 4 is preferable. Polyoxy C _2-4 alkylene glycol (such as diethylene glycol), bisphenols (such as bisphenols or alkylene oxide adducts thereof), etc. may be mentioned. Examples of dicarboxylic acids include C _6-12 aliphatic dicarboxylic acids (adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc.), asymmetric aromatic dicarboxylic acids in which the carboxyl group is substituted at the asymmetric position of the arene ring, 1,1 4-cyclohexanedimethanol etc. are mentioned. Among these compounds, aromatic compounds such as alkylene oxide adducts of bisphenols (especially bisphenol A) and asymmetric aromatic dicarboxylic acids [phthalic acid, isophthalic acid, and reactive derivatives thereof (dimethyl isophthalic acid (DMI) Etc.) and the like are preferable.

  The polybutylene terephthalate resin is preferably homopolyester (polybutylene terephthalate) and / or copolymer (polybutylene terephthalate copolyester), and the proportion (modification amount) of the copolymerizable monomer is usually 45 mol% or less (e.g. 0 to 40 mol%), preferably 35 mol% or less (e.g., 0 to 35 mol%), or 30 mol% or less (0 to 30 mol%). When used alone, the proportion of the copolymerizable monomer in the copolymer can be selected, for example, from the range of about 0.01 to 30 mol%, usually 1 to 30 mol%, preferably 3 to 25 mol% More preferably, it is about 5 to 20 mol% (for example, 5 to 15 mol%). When used in combination with a homopolyester, the proportion of the copolymerizable monomer in the copolymer can be selected, for example, from the range of about 0.1 to 45 mol%, and is usually 1 to 40 mol% (for example, 5 to 40 mol %), Preferably about 10 to 35 mol%.

  When the homopolyester (polybutylene terephthalate) and the copolymer are used in combination, the ratio of the homopolyester to the copolyester is such that the proportion of the copolymerizable monomer is 0.1 to the total monomer. It is a range of about 30 mol% (preferably 1 to 25 mol%, more preferably 5 to 25 mol%), and usually, the weight ratio of homopolyester / copolyester is 99/1 to 1/99, preferably It can be selected from the range of about 95/5 to 5/95, more preferably about 90/10 to 10/90.

  Polybutylene terephthalate resin is copolymerized with terephthalic acid or a reactive derivative thereof and a monomer which is optionally copolymerizable with 1,4-butanediol by a conventional method, for example, transesterification, direct esterification method, etc. It can be manufactured by

  The content of the polybutylene terephthalate resin is 50% by mass or more in the entire PBT resin composition in that the various properties such as mechanical properties, electrical properties, heat resistance, chemical resistance and solvent resistance are sufficiently exhibited. Preferably, it can be 60% by mass or more, more preferably 65% by mass or more.

The amount of terminal carboxyl groups of the polybutylene terephthalate resin is preferably 50 meq / kg or less, and particularly preferably 35 meq / kg or less, in terms of further enhancing the alkali solution resistance. The lower limit of the amount of terminal carboxyl groups of the polybutylene terephthalate resin is not particularly limited, but when the amount of terminal carboxyl groups of the polybutylene terephthalate resin is extremely low, (B) epoxy resin, and optionally for the purpose of improving mechanical characteristics. 1 meq / kg or more, preferably 5 meq or more, in that the reaction with the surface treatment agent of the inorganic filler such as glass fiber to be added may be insufficient, and it may be difficult to obtain alkali solution resistance and mechanical properties. It can be more than / kg.
The amount of terminal carboxyl group of polybutylene terephthalate resin is determined by dissolving a crushed sample of polybutylene terephthalate resin in benzyl alcohol at 215 ° C. for 10 minutes and then titrating with a 0.01 N aqueous solution of sodium hydroxide to measure. Be

  The intrinsic viscosity of the polybutylene terephthalate resin is not particularly limited as long as the object of the present invention is not impaired, but it is preferably 0.60 dL / g to 1.2 dL / g, more preferably 0.65 dL / g to 0. .9 dL / g or less. When using the polybutylene terephthalate resin of the intrinsic viscosity of this range, the PBT resin composition obtained will be particularly excellent in moldability. The intrinsic viscosity can also be adjusted by blending polybutylene terephthalate resins having different intrinsic viscosities. For example, a polybutylene terephthalate resin having an inherent viscosity of 0.9 dL / g is prepared by blending a polybutylene terephthalate resin having an inherent viscosity of 1.0 dL / g and a polybutylene terephthalate resin having an inherent viscosity of 0.7 dL / g. Can. The intrinsic viscosity (IV) of the polybutylene terephthalate resin can be measured, for example, in o-chlorophenol at a temperature of 35 ° C.

((B) Epoxy resin)
Examples of the epoxy resin include polyfunctional epoxy resins and vinyl copolymers having a glycidyl group. The epoxy resins can be used alone or in combination of two or more.

  As a polyfunctional epoxy resin, for example, glycidyl ether type epoxy resin, glycidyl ester type epoxy resin (diglycidyl phthalate, diglycidyl tetrahydro phthalate, diglycidyl hexahydrophthalate, dimethyl glycidyl phthalate, dimethyl glycidyl hexahydro phthalate, dimer acid glycidyl ester , Aromatic diglycidyl ester, cycloaliphatic diglycidyl ester, etc., glycidyl amine type epoxy resin (tetraglycidyl diaminodiphenylmethane, triglycidyl para aminophenol, triglycidyl meta amino phenol, diglycidyl toluidine, tetraglycidyl toxylylene) Amines, diglycidyl tribromoaniline, tetraglycidyl bisaminomethyl Hexahexane etc.), Heterocyclic epoxy resin (triglycidyl isocyanurate, hydantoin type epoxy resin etc.), Cyclic aliphatic epoxy resin (Vinylcyclohexene dioxide, dicyclopentadiene oxide, Alicyclic diepoxy acetal, Alicyclic Diepoxy adipate, aryl cyclic diepoxy carboxylate and the like), epoxidized polybutadiene and the like.

  As the glycidyl ether type epoxy resin, glycidyl ether of polyhydroxy compound [bisphenol type epoxy resin (for example, bisphenol A type (Bis-A type), bisphenol AD type, bisphenol F type epoxy resin, etc.), resorcinol type epoxy resin, etc. Glycidyl ethers of aromatic polyhydroxy compounds; aliphatic epoxy resins (such as alkylene glycols and glycidyl ethers of polyoxyalkylene glycols); novolac epoxy resins (such as phenol nopolac type and cresol novolac epoxy resins); Be

  The vinyl copolymer having a glycidyl group is composed of a copolymer of a polymerizable monomer having a glycidyl group (such as a vinyl monomer having a glycidyl group) and another copolymerizable monomer. Ru.

  The polymerizable monomer having a glycidyl group has, along with the glycidyl group, at least one polymerizable group (such as an ethylenically unsaturated bond (such as a vinyl group) or an acetylene bond). Such monomers include glycidyl ethers such as allyl glycidyl ether, vinyl glycidyl ether, chalcone glycidyl ether, 2-cyclohexene-1-glycidyl ether; glycidyl (meth) acrylate, glycidyl maleate, glycidyl itaconate, vinyl benzoic acid Acid glycidyl ester, allyl benzoate glycidyl ester, cinnamate glycidyl ester, cinnamylidene glycidyl ester, dimer acid glycidyl ester, epoxidized ester of stearyl alcohol and acrylic acid or methacrylic acid, alicyclic glycidyl ester (cyclohexene-4, Glycidyl or epoxy esters such as 5-diglycidyl carboxylate etc. (especially glycidyl esters of α, β-unsaturated carboxylic acids etc) Epoxidized unsaturated linear or cyclic olefins such as epoxyhexene and limonene oxide; N- [4- (2,3-epoxypropoxy) -3,5-dimethylbenzyl] acrylamide and the like. Among these monomers, vinyl monomers having a glycidyl group, for example, glycidyl esters of α, β-unsaturated carboxylic acids are preferred. These glycidyl group-containing polymerizable monomers can be used alone or in combination of two or more.

  Examples of the other copolymerizable monomers copolymerizable with the polymerizable monomer having a glycidyl group include olefin monomers (such as ethylene, propylene, α-olefins such as butene and hexene), and diene based monomers. Monomers (such as conjugated dienes such as butadiene and isoprene), aromatic vinyl monomers (such as styrene monomers such as styrene, α-methylstyrene and vinyl toluene), acrylic monomers ((meth) acrylics Acids, (meth) acrylic acid alkyl esters such as methyl methacrylate, acrylonitrile and the like), vinyl esters (vinyl acetate, vinyl propionate and the like), vinyl ethers and the like can be mentioned. The copolymerizable monomer is preferably a monomer having an α, β-unsaturated double bond. These copolymerizable monomers can be used alone or in combination of two or more. Among the copolymerizable monomers, olefin monomers, acrylic monomers ((meth) acrylic acid, (meth) acrylic acid ester, etc.) and the like are preferable.

  The addition amount of the epoxy resin is an amount such that the amount of epoxy groups is 0.5 to 1.5 when the amount of terminal carboxyl groups of (A) polybutylene terephthalate resin in the polybutylene terephthalate resin composition is 1. Preferably, the amount is 0.8 to 1.2. In addition, "the amount of epoxy groups" is a value calculated | required by the epoxy equivalent (g / eq) based on the chemical structure of the epoxy resin to add, and the addition amount of the said epoxy resin in a polybutylene-terephthalate-resin composition. By containing the epoxy resin in an amount of 0.5 to 1.5, it is possible to obtain a PBT resin composition excellent in alkali solution resistance while suppressing an increase in viscosity.

((C) silicone compound)
The PBT resin composition contains a silicone compound at a point of further improving the alkali solution resistance. According to the study of the present inventor, the alkali solution resistance is improved more in the case of adding the epoxy resin and the silicone compound than in the case of adding only the epoxy resin to the PBT resin, but such PBT resin composition is particularly good. It was found that when the substance was allowed to stay in the molten state for a long time, the increase in viscosity became remarkable and the fluidity further decreased. However, according to the polybutylene terephthalate resin composition according to the present embodiment, even in the case of containing an epoxy resin and a silicone compound, a PBT resin composition having both excellent flowability and resistance to alkaline solution can be obtained. Can.

As a silicone type compound, the liquid organopolysiloxane which has a siloxane bond in a principal chain can be mentioned, The kind in particular is not limited. For example, the following general formula (1)
R ₃ SiO [R ₂ SiO] _n SiR ₃ (1)
(Wherein R is a substituted or unsubstituted monovalent hydrocarbon group or a hydroxyl group, and n is an integer). In the above formula, R represents an alkyl group such as methyl, ethyl or propyl; an alkenyl group such as vinyl or allyl; an aralkyl group such as cycloalkyl or β-phenylethyl; 3,3,3-tri It is a substituted or unsubstituted monovalent hydrocarbon group exemplified by fluoropropyl group, 3-mercaptopropyl group, 3-aminopropyl group, 3-glycidoxypropyl group and the like.

  Specific examples of silicone compounds include: pure silicone resins such as dimethylpolysiloxane, methylphenylpolysiloxane and diphenylpolysiloxane generally used as silicone oils; pure silicone resins; alkyd resins; polyester resins; acrylic resins; A modified silicone reacted with a modifying resin such as a resin may, for example, be mentioned. One or more selected from these can be used.

  The content of the silicone compound is preferably 0.5 to 5 parts by mass, more preferably 0. 5 parts by mass with respect to 100 parts by mass of the (A) polybutylene terephthalate resin, from the viewpoint of further enhancing the alkali solution resistance. 8 to 2 parts by mass.

  The molecular weight of the silicone-based compound is not particularly limited, but is preferably liquid as the silicone-based compound, and particularly preferably one having a kinematic viscosity of 100 to 200000 cSt at 25 ° C. More preferably, it is in the range of 1000 to 60000 cSt, especially 3000 to 10000 cSt.

((D) Phosphorus compound)
The phosphorus-based compound includes at least one selected from organic phosphorus-based compounds and inorganic phosphorus-based compounds. Examples of organic phosphorus compounds include organic phosphate compounds, organic phosphite compounds, organic phosphonate compounds, organic phosphonite compounds and the like. Examples of inorganic phosphorus compounds include alkali metal phosphates and alkaline earth metal phosphates. The phosphorus-based compound may be liquid or solid.

Examples of organic phosphate compounds include mono to trialkyl esters of phosphoric acid (eg, mono to di C _6-24 alkyl esters such as monostearyl acid phosphate, distearyl acid phosphate, etc.), mono to triaryl esters of phosphoric acid (mono ester Or mono- or di-C _6-10 aryl esters such as diphenyl phosphate etc.) and the like.

  As the organic phosphite compound, for example, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butyl-4-methylphenyl) penta Erythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite and the like.

As an organic phosphonate compound, mono- or dialkyl phosphonates (C _6-24 alkyl phosphonate etc.) such as distearyl phosphonate; and aryl phosphonates which may have a substituent on the aryl group such as diphenyl phosphonate and di (nonylphenyl) phosphonate ( _C6-10 aryl phosphonate etc.); mono- or di-aralkyl phosphonates ((C _6-10 aryl-C _1-6 alkyl) phosphonate etc.) such as dibenzyl phosphonate etc. may be mentioned.

  Examples of the organic phosphonite compound include tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene phosphonite and the like.

  Examples of alkali metal phosphates include phosphates or corresponding hydrogen phosphates (eg, potassium phosphate, sodium phosphate [(monosodium phosphate (sodium dihydrogenphosphate), disodium phosphate (hydrogen phosphate) And alkali metal salts such as sodium, sodium monohydrogenphosphate, disodium hydrogenphosphate etc.) and the like.

  As the alkaline earth metal phosphate, calcium phosphate (calcium phosphate (calcium dihydrogen phosphate, calcium bis (dihydrogen phosphate) monohydrate etc.), dibasic calcium phosphate (calcium hydrogen phosphate, calcium hydrogen phosphate) Dihydrate etc. and the like], alkaline earth metal salts such as magnesium phosphate (magnesium hydrogen phosphate, magnesium dihydrogen phosphate etc.) and the like. The alkali metal salt or alkaline earth metal salt may be either anhydrous or hydrous.

  It is preferable to contain 1 type, or 2 or more types selected from an alkali metal phosphate, an alkaline earth metal phosphate, and an organic phosphite compound among these phosphorus compounds. In addition, when the PBT resin composition is used for a molded article application to be bonded to another member using a silicone adhesive, it contains an alkali metal phosphate and / or a metal alkaline earth salt in terms of enhancing the adhesive strength. Is preferable, and it is more preferable to contain sodium dihydrogen phosphate.

  The content of the (D) phosphorus compound is 0.05 to 0.5 parts by mass, preferably 0.05 to 0.3 parts by mass with respect to 100 parts by mass of the (A) polybutylene terephthalate resin. More preferably, it is 0.08-0.2 mass part. By making content of a phosphorus compound into the said range, it can be set as the PBT resin composition which can be compatible in the outstanding fluidity | liquidity and alkali-proof solution resistance.

(Other ingredients)
The polybutylene terephthalate resin composition of one embodiment of the present invention can contain other components as needed. Other components include, for example, inorganic fillers, antioxidants, weathering stabilizers, molecular weight modifiers, UV absorbers, antistatic agents, dyes, pigments, lubricants, crystallization accelerators, crystal nucleating agents, near infrared rays Although an absorbent, a flame retardant, a flame retardant auxiliary, an organic filler, a coloring agent etc. are mentioned, it is not limited to these.

  As the inorganic filler, for example, a fibrous, particulate or plate-like inorganic filler can be used. Examples of fibrous inorganic fillers include glass fibers, asbestos fibers, silica fibers, silica / alumina fibers, alumina fibers, zirconia fibers, boron nitride fibers, silicon nitride fibers, boron fibers, potassium titanate fibers, and further stainless steel, aluminum, titanium And fibrous materials of metals such as copper and brass. In addition, as the granular filler, silica, quartz powder, glass beads, milled glass fiber, glass balloon, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, wollastonite, etc., silicate, oxidized Oxides of metals such as iron oxide, titanium oxide, zinc oxide, antimony trioxide and alumina, carbonates of metals such as calcium carbonate and magnesium carbonate, sulfates of metals such as calcium sulfate and barium sulfate, other ferrites, silicon carbide, Silicon nitride, boron nitride, various metal powders and the like can be exemplified. Moreover, as a plate-like filler, mica | cuttle-fish, glass flakes, various metal foil etc. can be illustrated. The size of the inorganic filler is not particularly limited as long as the effect of the present invention is not impaired.

  Although content of an inorganic filler is not specifically limited, It is preferable that it is 40-100 mass parts with respect to 100 mass parts of (A) PBT resin, and it is more preferable that it is 45-80 mass parts. When the content of the inorganic filler is in the above-mentioned range, the strength of the molded article can be further enhanced.

  Examples of the antioxidant include hindered phenol-based, thioether-based and hindered amine-based antioxidants, and one or more selected from these may be used. The content of the antioxidant is not particularly limited, and is determined according to the purpose. For example, it can be 0.01 to 5 parts by mass with respect to 100 parts by mass of PBT resin.

  The colorant is not particularly limited, and examples thereof include inorganic pigments, organic pigments, dyes and the like. Examples of the inorganic pigment include black pigments such as carbon black and carbon nanotubes, red pigments such as iron oxide red, orange pigments such as molybdate orange, and white pigments such as titanium oxide. Examples of organic pigments include yellow pigments, orange pigments, red pigments, blue pigments, green pigments and the like. These coloring agents B can be used alone or in combination of two or more. In addition, the coloring agent B may be one whose surface is treated with an acid or the like. The content of the colorant can be, for example, 0.01 to 5 parts by mass with respect to 100 parts by mass of the PBT resin composition.

  In addition, the polybutylene terephthalate resin composition according to an embodiment of the present invention may contain other crystalline resin such as PET resin, as long as the effects of the present invention are not impaired. Polycarbonate resin (PC resin), polytrile Amorphous resins such as methylene terephthalate resin (PTT resin), polycyclohexylene dimethylene terephthalate resin (PCT resin), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-styrene-butadiene copolymer (ABS resin), etc. May be included. One of these resins may be used alone, or two or more of these resins may be used in combination.

  However, when a polyester-based resin other than PBT resin is contained, the transesterification with (A) PBT resin may affect the moldability and mechanical properties, so the polybutylene terephthalate resin composition of the present invention It is preferable not to contain polyester-based resin other than PBT resin, and when it contains polyester-based resin other than PBT resin, it is preferable that it is 10 mass% or less of the whole polybutylene terephthalate resin composition, and 5 mass%. It is more preferable that

  In addition, the polybutylene terephthalate resin composition of one embodiment of the present invention may contain a thermoplastic elastomer in order to improve impact resistance. The type of the thermoplastic elastomer is not particularly limited, and examples thereof include olefin elastomers, styrene elastomers, polyester elastomers, polyamide elastomers and urethane elastomers.

  Preferred as the olefin elastomer are copolymers mainly composed of ethylene and / or propylene, and specifically, ethylene-propylene copolymers, ethylene-butene copolymers, ethylene-octene copolymers, ethylene -Propylene-butene copolymer, ethylene-propylene-diene copolymer, ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-glycidyl methacrylate copolymer, etc. Although it is mentioned, it is not limited to this.

  Examples of styrenic elastomers include block copolymers comprising a polymer block mainly composed of a vinyl aromatic compound such as styrene and a polymer block mainly composed of a nonhydrogenated and / or hydrogenated conjugated diene compound. .

  Examples of polyester elastomers include aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate as hard segments, polyethers such as polyethylene glycol and polytetramethylene glycol, or aliphatic polyesters such as polyethylene adipate, polybutylene adipate, and polycaprolactone as soft. Although the block copolymer made into a segment is mentioned, It is not limited to this.

  Examples of polyamide-based elastomers include, but are not limited to, block copolymers in which nylon 6, nylon 66, nylon 11, nylon 12 or the like is a hard segment and polyether or aliphatic polyester is a soft segment. It is not a thing.

  Examples of urethane elastomers include reaction of diisocyanates such as 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate with glycols such as ethylene glycol and tetramethylene glycol. Block copolymers containing as a hard segment the polyurethane obtained by the above process and a polyether or polyethylene adipate such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol or an aliphatic polyester such as polybutylene adipate or polycaprolactone as a soft segment However, it is not limited to this.

  The content of the thermoplastic elastomer is preferably 10 to 30 parts by mass, more preferably 12 to 20 parts by mass with respect to 100 parts by mass of (A) PBT resin.

(PBT resin composition)
The polybutylene terephthalate resin composition is MFR of a melt flow rate (MFR) after staying for 60 minutes at 260 ° C. in a melt flow rate tester defined in ISO 1133, after staying for 7 minutes at 260 ° C. Ratio to MFR (MFR at retention for 60 minutes / MFR at retention for 7 minutes) is preferably 0.8 to 5, more preferably 0.9 to 4, and particularly preferably 1 to 3. is there. By setting the MFR at retention for 60 minutes or MFR at retention for 7 minutes to 0.8 or more, the increase in viscosity is suppressed even when the PBT resin composition stays in the cylinder at a high temperature for a long time at the time of molding The viscosity suitable for the above can be maintained, and a decrease in mechanical physical properties can be suppressed by setting the viscosity to 5 or less.

  The form of the polybutylene terephthalate resin composition may be a powder mixture, or may be a melt mixture (melt-kneaded product) such as pellets. The method for producing the polybutylene terephthalate resin composition is not particularly limited, and can be produced using equipment and methods known in the art. For example, necessary components can be mixed and kneaded using a single- or twin-screw extruder or other melt-kneading apparatus to prepare molding pellets. A plurality of extruders or other melt kneading apparatuses may be used. Moreover, all the components may be simultaneously fed from the hopper, or some components may be fed from the side feed port.

(Use)
The application of the polybutylene terephthalate resin composition is not particularly limited, and can be widely used in various applications such as automotive parts and electric / electronic parts. In particular, since this polybutylene terephthalate resin composition is excellent in alkali solution resistance, it can be suitably used for a molded article to be in contact with an alkaline solution such as a detergent or a snow melting agent. In addition, when producing a molded product having a thin-walled portion, generally, in order to ensure the fluidity for filling the resin in the thin-walled portion of the mold, it is necessary to increase the molding temperature. In polybutylene terephthalate resin compositions to which an epoxy resin and a silicone compound have been added to impart alkaline solution properties, a dilemma occurs in which, when staying in the molten state, the increase in viscosity becomes remarkable and the flowability decreases. In contrast, the polybutylene terephthalate resin composition of the present embodiment is excellent in moldability because the decrease in fluidity is suppressed even when staying at a high temperature. Therefore, this polybutylene terephthalate resin composition can be suitably used for a molded article having a thin-walled portion having a thickness of 1 mm or less at least partially.

Also, in general, when the injection amount of the resin composition per mold is small as in the production of small parts, the time for which the resin composition stays in the molding machine becomes long, and the resin composition Things are often heated for a long time. The conventional PBT resin containing an epoxy resin and a silicone compound tends to further increase the viscosity of the resin composition when the heating time becomes long. However, the polybutylene terephthalate resin composition according to the present embodiment is excellent in fluidity even when heated for a long time. Therefore, this PBT resin composition can be suitably used also for molded articles used as small parts having a volume of molded articles of 20 cm ³ or less.

  In addition, when the polybutylene terephthalate resin composition is used for a case of an automobile sensor, an ECU case, and the like, adhesion and potting may be performed with an addition type silicone adhesive or the like. In this case, the phosphorus compound may be a substance inhibiting the effect of the silicone adhesive, but when it contains an alkali metal phosphate and / or an alkaline earth metal phosphate, there are very few cases that cause curing inhibition. A molded article using the PBT resin composition is excellent in adhesive strength with other parts by a silicone adhesive. Therefore, it can be suitably used for a molded article to be laminated with another member via a silicone adhesive layer, or for a molded article having a silicone adhesive layer on at least one surface.

[Molding]
The molded article according to the present embodiment is a molded article molded using the above-described polybutylene terephthalate resin composition. The molding method of the molded article is not particularly limited, and can be formed by, for example, conventionally known injection molding, extrusion molding, blow molding (various hollow molded articles), vacuum molding, compression molding or the like. The molded article may have a thickness of at least 1 mm in at least a part of the portion containing the polybutylene terephthalate resin composition. The molded article may be used as a small part having a volume of 20 cm ³ or less. Furthermore, in the case of a molded article molded using the above PBT resin composition containing an alkali metal phosphate and / or an alkaline earth metal phosphate, a molding is made to be laminated with another member via a silicone adhesive layer. The article may be a molded article having a silicone adhesive layer on at least one surface.

[Complex]
The composite according to the present embodiment includes a molded article molded using the above PBT resin composition containing an alkali metal phosphate and / or an alkaline earth metal phosphate and at least one surface of the molded article. And having a silicone adhesive layer formed thereon. A conventionally known silicone adhesive can be used as the silicone adhesive constituting the silicone adhesive layer. The silicone adhesive is an adhesive that cures at room temperature or by heating, and conventionally known ones can be used. For example, mention is made of an addition reaction type silicone adhesive whose effect is promoted by an addition reaction with a platinum-based catalyst. Can.

  A composite is obtained by bonding a molded article formed using the above PBT resin composition containing an alkali metal phosphate and / or an alkaline earth metal phosphate with another member with a silicone adhesive. May be. The composite in this case has a configuration in which a molded product molded using a PBT resin composition and other members are laminated via a silicone adhesive layer. Examples of other members include molded articles of metals, alloys, inorganic solids or resins. The metal, alloy or inorganic solid is not particularly limited and can be selected according to the purpose. The resin is preferably one that does not inhibit the curing of the silicone-based adhesive, and in terms of having alkali solution resistance, it is preferable to use the above PBT resin composition.

  EXAMPLES The present invention will be described in more detail by the following examples, but the present invention is not limited to these examples.

[material]
The details of the components used are as follows.
(A) Polybutylene terephthalate resin PBT resin: manufactured by Wintech Polymer Co., Ltd., terminal carboxyl group weight 18 meq / kg, intrinsic viscosity (IV) = 0.88 dL / g
(B) Epoxy resin Bis-A type epoxy resin (Mitsubishi Chemical Corporation, 1004), (epoxy equivalent 900 g / eq)
(C) Silicone Compound Dimethylpolysiloxane (manufactured by Toray Dow Corning, SH-200)
In addition to the above, glass fibers (ECS03T-127, manufactured by Nippon Electric Glass Co., Ltd., manufactured by Nippon Electric Glass Co., Ltd.), ethylene ethyl acrylate as an elastomer, and a coloring agent are added to the resin compositions of the Examples and Comparative Examples. Carbon black was added in the amounts shown in Table 1 respectively.
(D) Phosphorus Compound Compound 1: Sodium dihydrogen phosphate (manufactured by Yoneyama Chemical Co., Ltd.)
Compound 2: bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite (manufactured by ADEKA Co., Ltd., Adekastab PEP36)
(D ') Compounds other than phosphorus compounds Compound 3: Tetrakis [methylene-3- (dodecylthio) propionate] methane (ADEKA Corporation, Adekastab AO-412S)
Compound 4: potassium acetate (manufactured by Wako Pure Chemical Industries, Ltd.)
Compound 5: Tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane (manufactured by BASF Japan Ltd., Irganox 1010)

(Epoxy group amount)
The amount of epoxy groups derived from the epoxy resin when the amount of terminal carboxyl groups of the polybutylene terephthalate resin was 1 was determined as follows.
(Epoxy resin derived epoxy resin content in PBT resin composition) ÷ (carboxyl content derived from PBT resin in PBT resin composition) = (content of epoxy resin in PBT resin composition [kg] kg epoxy concerned Epoxy equivalent of resin [kg / meq]) (Content of PBT resin in PBT resin composition [kg] x amount of terminal carboxyl groups of PBT resin [meq / kg])

[Examples 1 to 4, Comparative Examples 1 to 12]
The components shown in Table 1 are dry-blended according to the composition (parts by mass) shown in Table 1, supplied from a hopper to a twin-screw extruder (made by Japan Steel Works Ltd.) having a 30 mmφ screw and melt-kneaded at 260 ° C. The pellet-like PBT resin composition was obtained.

[Evaluation]
About the obtained PBT resin composition, fluidity (MFR) and alkali solution resistance of a molded article were evaluated based on the following. The results are shown in Table 1.

(MFR for 7 minutes)
MFR (g / 10 min) immediately after retaining for 2 minutes at 260 ° C. for 7 minutes was measured using MELT INDEXER L202 manufactured by Takara Co., Ltd., Thermistor.

(MFR for 60 minutes)
A MFR (g / 10 min) immediately after holding at a load of 2160 g at 260 ° C. for 60 minutes was measured using MELT INDEXER L202 manufactured by Takara Co., Ltd. Thermistor.

(MFR for 60 minutes / MFR for 7 minutes)
From the numerical values obtained above, the ratio of MFR immediately after being held for 60 minutes to MFR immediately after being held for 7 minutes (MFR for 60 minutes / MFR for 7 minutes) was calculated.

(Alkali-resistant solution resistance)
The pellets of the PBT resin composition are dried at 140 ° C. for 3 hours, and then the test piece molding die (80 mm long, horizontal) with a cylinder temperature of 250 ° C., a mold temperature of 70 ° C., an injection time of 20 seconds and a cooling time of 10 seconds. A flat plate forming mold of 80 mm in thickness and 1 mm in thickness. A pin of 2 mm in width × 1 mm in thickness provided at the side center of one side of the flat plate by installing a pin at a position corresponding to the approximate center of one main surface of the flat plate. When filling the resin from the gate, injection molding was carried out using “where welds are generated on one principal surface of the flat plate” to produce a welded flat-plate-formed article. The obtained flat molded article with weld was cut into a strip of 10 mm in width and 80 mm in length so that a substantially central portion in the longitudinal direction would be weld, to prepare a test piece. The test piece was fixed to a jig in a bent state so that a bending strain of 1.0% was always applied to the weld. In this state, the entire jig is immersed in a 10% sodium hydroxide solution, left at an ambient temperature of 23 ° C., and cracks occur in the test piece at 12 hours and 48 hours after the start of immersion. It was observed whether or not to The evaluation is performed using the test pieces of three pieces for each of the pellets of the example and the comparative example, and if none of the three test pieces has a crack, "1", one of the three test pieces. The alkali solution resistance was evaluated as "2" if cracks occurred even if individual pieces were generated.

(Hydrolytic resistance)
After the pellets of the PBT resin composition were dried at 140 ° C. for 3 hours, 1A-type tensile test pieces in accordance with ISO 3167 were produced at a cylinder temperature of 250 ° C. and a mold temperature of 70 ° C. The tensile strength of the obtained tensile test piece was measured in accordance with ISO 527-1. Moreover, the tensile test piece manufactured similarly was processed on the conditions of 121 degreeC, 100% RH for 48 hours, the tensile strength after a process was measured, and the strength retention before and behind a process was calculated | required. The hydrolysis resistance was evaluated by setting the one having a strength retention of 80% or more as “1” and the one having less than 80% as “2”.

(Silicone adhesion)
After the pellets of the PBT resin composition were dried at 140 ° C. for 3 hours, 1A-type tensile test pieces in accordance with ISO 3167 were produced at a cylinder temperature of 250 ° C. and a mold temperature of 70 ° C. The central part of the tensile test piece is cut, and a 7 mm × 7 mm hole is attached to one side of a nitroflon tape (0.18 mm thickness), and a silicone adhesive (Toray Dow Corning Co., Ltd.) is formed on the hole portion. SE1714) was applied. After application, the other cut tensile test pieces were overlapped so as to be a combination of molded articles before cutting, fixed by clips, and heat-treated at 120 ° C. for 1 hour. After the heat treatment, the clip was removed to confirm the cured state of the adhesive. Adhesiveness was evaluated by setting “1” for which the adhesive was cured and the test pieces could be bonded and “2” for those in which the test pieces were not able to be bonded due to curing inhibition.

As shown in Table 1, the PBT resin compositions of Examples 1 to 4 are excellent in alkali resistance and hydrolysis resistance, and are allowed to stay for 7 minutes at 260 ° C. and for 60 minutes. Both are excellent in liquidity. In addition, the MFR for 60 minutes retention / the value of MFR for 7 minutes of retention was 0.8 or more, and it was possible to suppress the decrease in fluidity even when staying in the molten state for a long time.

Claims (11)

(A) 100 parts by mass of polybutylene terephthalate resin,
(B) An epoxy resin having an epoxy group weight of 0.5 to 1.5 when the terminal carboxyl group weight of (A) polybutylene terephthalate resin is 1,
The polybutylene-terephthalate-resin composition containing (C) 0.5-5 mass parts of silicone type compounds, and (D) 0.05-0.5 mass parts of phosphorus compounds.   (D) The phosphorus compound is one or more selected from an alkali metal phosphate, an alkaline earth metal phosphate, an organic phosphate compound, an organic phosphite compound, an organic phosphonate compound, and an organic phosphonite compound The polybutylene-terephthalate resin composition of Claim 1 which contains.   The poly according to claim 1 or 2, wherein the (D) phosphorus-based compound contains one or more selected from an alkali metal phosphate, an alkaline earth metal phosphate and an organic phosphite compound. Butylene terephthalate resin composition.   The polybutylene terephthalate resin composition according to any one of claims 1 to 3, wherein the (D) phosphorus-based compound contains an alkali metal phosphate and / or an alkaline earth metal phosphate.   The polybutylene terephthalate resin composition according to any one of claims 1 to 4, wherein the (D) phosphorus-based compound contains sodium dihydrogen phosphate.   The polybutylene terephthalate resin composition according to any one of claims 1 to 5, wherein the silicone compound (C) contains a silicone oil.   The polybutylene terephthalate resin composition according to any one of claims 1 to 6, which is for a molded article having a thin-walled portion having a thickness of 1 mm or less at least partially.   The polybutylene terephthalate resin composition according to any one of claims 4 to 7, which is for a molded article having a silicone adhesive layer formed on at least one surface.   A molded article molded using the polybutylene terephthalate resin composition according to any one of claims 1 to 8.   The molded article according to claim 9, wherein a thickness of at least a part of a portion containing the polybutylene terephthalate resin composition is 1 mm or less.   A molded article molded using the polybutylene terephthalate resin composition according to any one of claims 4 to 8, and a silicone adhesive layer formed on at least one surface of the molded article, Complex.