JP6177190B2 - Polybutylene terephthalate resin composition - Google Patents

Description

  According to the present invention, a polyaromatic polyester having a specific composition is contained in a polyester resin, so that it has excellent moldability and a significantly improved weather resistance as compared with a single polybutylene terephthalate resin. The present invention relates to a butylene terephthalate resin composition.

  Polybutylene terephthalate resin is a crystalline plastic with a good balance of physical properties such as electrical properties, mechanical properties, and heat resistance, and has good dimensional stability and thermal stability. Used for electronic parts and machine parts. In addition, it has excellent chemical resistance such as organic solvents, lubricants, gasoline, etc., so it is widely used in automobile parts. Recently, it is widely used in electrical parts of automobiles with more severe external environmental conditions. It is coming.

  When used in automobile electrical parts, it is required to withstand the environment of sunlight, other light, rainwater, moisture, oxygen, ozone, NOX, etc., and to maintain the strength and appearance of the parts stably for a long period of time. ing. However, polybutylene terephthalate resin may be hydrolyzed and deteriorated in long-term use under high temperature and high humidity. For use in outdoor natural environments such as automobile parts, weather resistance (light resistance) Improvement is demanded.

  In order to suppress the hydrolysis of the polybutylene terephthalate resin and improve the weather resistance, a resin composition (Patent Documents 1 and 2) containing a carbodiimide compound and an epoxy compound, a carbodiimide compound, an epoxy compound, and a polybutylene terephthalate resin A resin composition (Patent Document 3) containing a butadiene-based graft copolymer has been proposed. However, the effect of improving weather resistance in the resin compositions proposed in Patent Documents 1 to 3 is not sufficient, and further improvement in weather resistance is required.

Japanese Patent Laid-Open No. 56-161452 JP-A-1-174557 JP-A-60-219255

  An object of the present invention is to provide a polybutylene terephthalate resin having a high fluidity and good moldability in which the occurrence of burrs and sink marks is suppressed as compared with a single polybutylene terephthalate resin, and weather resistance is remarkably improved. It is to provide a composition. Another object of the present invention is to provide a polybutylene terephthalate resin composition in which a wholly aromatic liquid crystalline polyester is uniformly dispersed without adding a compatibilizing agent.

  As a result of diligent investigations on improving the weather resistance of polybutylene terephthalate resin, the present inventors added a compatibilizing agent by blending a polybutylene terephthalate resin with a low-melting wholly aromatic liquid crystal polyester comprising a predetermined repeating unit. The present inventors have found that a polybutylene terephthalate resin composition excellent in weather resistance can be obtained by easily compatibilizing resins with each other, without completing the present invention.

That is, the present invention includes a polybutylene terephthalate resin and 100 parts by weight of the polybutylene terephthalate resin, wherein the repeating unit represented by the formula [I] is contained in an amount of 25 mol% or more in all repeating units, and the melting point is 250 ° C. or less. A polybutylene terephthalate resin composition containing 0.1 to 100 parts by weight of a wholly aromatic liquid crystal polyester is provided.

  The polybutylene terephthalate resin composition of the present invention is excellent in weather resistance because the wholly aromatic liquid crystal polyester is uniformly dispersed in the polybutylene terephthalate resin, and is suitably used for products used in natural environments such as outdoors. It is done.

  In addition, the polybutylene terephthalate resin composition of the present invention is excellent in molding processability because the occurrence of burrs and sink marks is suppressed as compared with a single polybutylene terephthalate resin.

  Furthermore, since a compatibilizing agent is unnecessary when blending the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester, it can be used for blending inexpensively and easily. In addition, when the resin is blended using a compatibilizing agent, depending on the type of the compatibilizing agent, it may be thermally decomposed during kneading or molding, which may adversely affect the resin performance, but the polybutylene terephthalate resin composition of the present invention This risk can be avoided in goods.

  The polybutylene terephthalate resin used in the present invention is a copolymer obtained by a condensation reaction or transesterification reaction between terephthalic acid or an ester-forming derivative thereof and 1,4-butanediol or an ester-forming derivative thereof.

  The viscosity of the polybutylene terephthalate resin used in the present invention is not particularly limited as long as it can be melt kneaded, but the intrinsic viscosity when measured in a 0.5% O-chlorophenol solution at 25 ° C. A polybutylene terephthalate resin having a concentration of 0.36 to 1.60 dl / g is preferred. In particular, a polybutylene terephthalate resin having an intrinsic viscosity in the range of 0.42 to 1.25 dl / g is preferable from the viewpoint of moldability.

  The melting point of the polybutylene terephthalate resin used in the present invention is not particularly limited, but is preferably 180 ° C. or higher from the viewpoint of heat resistance, more preferably 200 ° C. or higher, particularly 220 ° C. or higher. It is preferable that

  In the present invention, “single polybutylene terephthalate resin” refers to a resin component containing only the above-mentioned polybutylene terephthalate resin.

  In the present invention, the wholly aromatic liquid crystal polyester blended in the polybutylene terephthalate resin is a polyester that forms an anisotropic melt phase, and is called a thermotropic liquid crystal polyester by those skilled in the art. The repeating unit shown in the figure is not particularly limited as long as it is a wholly aromatic liquid crystal polyester containing 25 mol% or more of all repeating units and having a melting point of 250 ° C. or less.

  The property of the anisotropic molten phase can be confirmed by a normal deflection inspection method using an orthogonal deflector, that is, by observing a sample placed on a hot stage in a nitrogen atmosphere.

  The main repeating units other than the repeating unit represented by the formula [I] constituting the wholly aromatic liquid crystal polyester used in the present invention are (1) an aromatic oxycarbonyl repeating unit, (2) an aromatic dicarbonyl repeating unit and ( 3) One or more selected from aromatic dioxy repeating units.

  The wholly aromatic liquid crystal polyesters composed of these repeating units may or may not form an anisotropic molten phase depending on the constituent components, the composition ratio in the polymer, and the sequence distribution. The wholly aromatic liquid crystalline polyester is limited to those forming an anisotropic melt phase.

  The wholly aromatic liquid crystalline polyester used in the present invention contains 25 mol% or more of the repeating unit represented by the formula [I], preferably 30 to 55 mol%, more preferably 35 to 45 mol%. Is included. When the repeating unit represented by the formula [I] is less than 25 mol% in all repeating units, the melting point of the liquid crystal polyester tends to increase, which is not preferable.

  Examples of the monomer that gives the repeating unit represented by the formula [I] include 6-hydroxy-2-naphthoic acid and ester-forming derivatives such as acylated products, ester derivatives, and acid halides.

  Specific examples of the monomer that gives the aromatic oxycarbonyl repeating unit other than the monomer that gives the repeating unit represented by the formula [I] include, for example, parahydroxybenzoic acid, metahydroxybenzoic acid, ortho Hydroxybenzoic acid, 5-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl- Examples include 3-benzoic acid, alkyl, alkoxy or halogen-substituted products thereof, and ester-forming derivatives such as acylated products, ester derivatives, and acid halides. Among these, parahydroxybenzoic acid is preferable from the viewpoint of easily adjusting the characteristics and melting point of the wholly aromatic liquid crystal polyester obtained.

  (2) Specific examples of monomers that give aromatic dicarbonyl repeating units include, for example, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. Acid, aromatic dicarboxylic acid such as 1,4-naphthalenedicarboxylic acid, 4,4′-dicarboxybiphenyl, alkyl, alkoxy or halogen-substituted products thereof, ester derivatives thereof, and ester-forming derivatives such as acid halides Is mentioned. Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferable because the mechanical properties, heat resistance, melting point, and moldability of the resulting wholly aromatic liquid crystal polyester can be easily adjusted to appropriate levels.

  (3) Specific examples of the monomer giving an aromatic dioxy repeating unit include, for example, hydroquinone, resorcin, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,4- Aromatic diols such as dihydroxynaphthalene, 4,4′-dihydroxybiphenyl, 3,3′-dihydroxybiphenyl, 3,4′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl ether, alkyl, alkoxy or halogen substituted products thereof And ester-forming derivatives such as acylated products thereof. Among these, hydroquinone and 4,4'-dihydroxybiphenyl are preferable from the viewpoint of the reactivity during polymerization and the characteristics of the wholly aromatic liquid crystal polyester obtained.

  As described above, the repeating unit contained in the wholly aromatic liquid crystal polyester used in the present invention and the monomer that gives it have been described. The wholly aromatic liquid crystal polyester used in the present invention has a melting point measured by a differential scanning calorimeter. What is necessary is just 250 degrees C or less, The thing whose melting | fusing point is 170-240 degreeC is preferable, and what is melting | fusing point is 180-230 degreeC.

  In the present specification and claims, the “melting point” refers to the melting point peak temperature measured by a differential scanning calorimeter (hereinafter abbreviated as DSC) at a heating rate of 20 ° C./min. It is what I have sought. More specifically, after observing the endothermic peak temperature (Tm1) observed when a liquid crystal polyester resin sample is measured at room temperature to 20 ° C./min, the temperature is 20 to 50 ° C. higher than Tm1. Hold for 10 minutes, then cool the sample to room temperature under a temperature drop condition of 20 ° C./min, and then observe the endothermic peak when measured again under a temperature rise condition of 20 ° C./min. The melting point of the liquid crystal polyester resin. As the measuring device, for example, Exstar 6000 manufactured by Seiko Instruments Inc. can be used.

  By using a wholly aromatic liquid crystal polyester having a melting point of 250 ° C. or less, it is possible to blend the wholly aromatic liquid crystal polyester while suppressing decomposition of the polybutylene terephthalate resin, and the wholly aromatic liquid crystal polyester is uniform in the polybutylene terephthalate continuous phase. To obtain a polybutylene terephthalate resin composition.

  When the melting point of the wholly aromatic liquid crystal polyester exceeds 250 ° C., the dispersion of the polybutylene terephthalate resin becomes insufficient, and the decomposition of the polybutylene terephthalate proceeds during kneading or molding. There is a possibility that excellent properties such as physical properties, heat resistance and moldability may not be obtained. Moreover, when melting | fusing point of wholly aromatic liquid crystalline polyester is less than 170 degreeC, there exists a tendency for the moldability and heat resistance which were excellent in polybutylene terephthalate to be impaired, or the improvement effect of sink marks to become small.

  The wholly aromatic liquid crystal polyester used in the present invention can measure logarithmic viscosity in pentafluorophenol. The wholly aromatic liquid crystal polyester used in the present invention preferably has a logarithmic viscosity of 0.3 dl / g or more in pentafluorophenol when measured at a concentration of 0.1 g / dl and a temperature of 60 ° C. What is 10 dl / g is more preferable, and what is 1-8 dl / g is still more preferable.

  Further, the wholly aromatic liquid crystalline polyester used in the present invention preferably has a melt viscosity of 1 to 1000 Pa · s, more preferably 5 to 300 Pa · s, as measured with a capillary rheometer.

［式中、Ａｒ_１およびＡｒ_２は、それぞれ一種以上の２価の芳香族基を表し、ｐ、ｑ、ｒおよびｓは、各繰返し単位の全芳香族液晶ポリエステル中での組成比（モル％）であり、以下の式を満たすものである：
０．４≦ｐ／ｑ≦２．０
２≦ｒ≦１５、および
２≦ｓ≦１５］。 In the present invention, as the wholly aromatic liquid crystalline polyester which satisfies the melting point range of 250 ° C. or less, wholly aromatic liquid crystal polyester is particularly preferably used constituted by repeating units represented by the formula below [I] ~ [IV] The

[In the formula, Ar ₁ and Ar ₂ each represent one or more divalent aromatic groups, and p, q, r, and s represent the composition ratio (mol%) in the wholly aromatic liquid crystal polyester of each repeating unit. And satisfies the following formula:
0.4 ≦ p / q ≦ 2.0
2 ≦ r ≦ 15, and 2 ≦ s ≦ 15].

Here, in addition to the repeating units represented by the formulas [I] to [IV] as the constituent components of the wholly aromatic liquid crystalline polyester, other repeating units may be used as long as the melting point of the wholly aromatic liquid crystalline polyester is 250 ° C. or lower. but it may also be contained.

  In one preferred embodiment of the present invention, the composition ratio of the repeating units represented by the formulas [I] to [IV] is p + q + r + s = 100 mol%.

  In the present specification and claims, the “divalent aromatic group” means an aromatic group having two substituents capable of forming an ester bond.

  The preferred wholly aromatic liquid crystal polyester is a repeating unit represented by the formula [I] and the formula [II] having a molar ratio (p / q) of 0.4 to 2.0, preferably 0.6. To 1.8, particularly preferably 0.8 to 1.6.

  In one embodiment, the wholly aromatic liquid crystal polyester preferably used in the present invention preferably contains 35 to 48 mol% of repeating units represented by the formula [I] and the formula [II], respectively. Those containing mol% are particularly preferred.

  The wholly aromatic liquid crystalline polyester preferably used in the present invention contains the repeating units represented by the formulas [I] and [II] in the above amounts as essential constituent units. II] is included in the above molar ratio to stably exhibit a low melting point of 250 ° C. or lower.

  In the wholly aromatic liquid crystal polyester preferably used in the present invention, the repeating units represented by the formula [III] and the formula [IV] are preferably 2 to 15 mol%, more preferably 5 to 13 mol%, respectively. The content of the repeating unit represented by the formula [III] and the formula [IV] is preferably equimolar.

  The monomer giving the repeating unit represented by the formula [I] is as described above.

  Examples of the monomer that gives the repeating unit represented by the formula [II] include parahydroxybenzoic acid and ester-forming derivatives thereof such as acylated products, ester derivatives, and acid halides.

  Examples of the monomer that gives the repeating unit represented by the formula [III] include hydroquinone, resorcin, 4,4′-dihydroxybiphenyl, 3,3′-dihydroxybiphenyl, 3,4′-dihydroxybiphenyl, and 4,4 ′. -Ester formation of aromatic diols such as dihydroxybiphenyl ether, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, alkyl, alkoxy or halogen substituted products thereof, and acylated products thereof Sex derivatives.

  Monomers that give the repeating unit represented by the formula [IV] include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4, Aromatic dicarboxylic acids such as 4′-dicarboxybiphenyl and bis (4-carboxyphenyl) ether, alkyl, alkoxy or halogen-substituted products thereof, and ester-forming derivatives such as ester derivatives and acid halides thereof. .

および／または

であり、
式［ＩＶ］中のＡｒ_２が、

および／または

であるものである。 In one preferred embodiment, the repeating unit represented by the formula [III] and the formula [IV] is represented by Ar ₁ in the formula [III]:

And / or

And
Ar ₂ in formula [IV] is

And / or

It is what is.

  The wholly aromatic liquid crystal polyester used in the present invention is not limited to the main monomer in the wholly aromatic liquid crystal polyester of the present invention that gives the repeating units represented by the above general formulas [I] to [IV]. As long as the purpose is not impaired, the main monomer may be another type of aromatic hydroxycarboxylic acid, aromatic diol, aromatic dicarboxylic acid, or aromatic hydroxydicarboxylic acid, aromatic hydroxyamine, aromatic diamine, aromatic A copolymer obtained by copolymerizing aminocarboxylic acid, aromatic mercaptocarboxylic acid, aromatic dithiol, aromatic mercaptophenol or the like as another monomer component may be used. The ratio of these other monomer components is preferably 10 mol% or less with respect to the total of the monomer components giving the repeating units represented by the general formulas [I] to [IV].

  There is no particular limitation on the method for producing the wholly aromatic liquid crystal polyester used as the resin component in the resin composition of the present invention, and a known polyester polycondensation method for forming an ester bond with the monomer component, for example, melting An acidolysis method, a slurry polymerization method, etc. can be used.

  The melt acidolysis method is a method suitable for producing the wholly aromatic liquid crystal polyester used in the present invention. In this method, the monomer is first heated to form a melt of the reactant, and the reaction is performed. The molten polymer is obtained by continuing. A vacuum may be applied to facilitate removal of volatiles (for example, acetic acid, water, etc.) by-produced in the final stage of condensation.

  The slurry polymerization method is a method of reacting in the presence of a heat exchange fluid, and the solid product is obtained in a state suspended in a heat exchange medium.

  In both the melt acidification method and the slurry polymerization method, the polymerizable monomer component used in producing the liquid crystal polyester is reacted at room temperature as a modified form in which a hydroxyl group is acylated, that is, a lower acylated product. Can also be provided. The lower acyl group preferably has 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms. Particularly preferred is a method using an acetylated product of the monomer component in the reaction.

  The lower acylated product of the monomer may be separately acylated and synthesized in advance, or may be produced in the reaction system by adding an acylating agent such as acetic anhydride to the monomer during the production of the liquid crystalline polyester. .

  In either case of the melt acidolysis method or the slurry polymerization method, a catalyst may be used as needed during the reaction.

Specific examples of the catalyst include organic tin compounds such as dialkyltin oxide (for example, dibutyltin oxide) and diaryltin oxide; organic titanium compounds such as titanium dioxide, antimony trioxide, alkoxy titanium silicate, and titanium alkoxide; alkali and alkali of carboxylic acid Examples include earth metal salts (for example, potassium acetate); gaseous acids catalysts such as Lewis acids (for example, BF ₃ ) and hydrogen halides (for example, HCl).

  The ratio of the catalyst used is usually 10 to 1000 ppm, preferably 20 to 200 ppm, based on the monomer.

  The wholly aromatic liquid crystalline polyester obtained by such a polycondensation reaction is extracted from the polymerization reaction tank in a molten state, and then processed into pellets, flakes, or powders, and blended with polybutylene terephthalate resin. To be served.

  In the polybutylene terephthalate resin composition of the present invention, the blending ratio of the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester is 0.1 to 100 parts by weight of the wholly aromatic liquid crystal polyester, preferably 100 parts by weight of the polybutylene terephthalate resin. Is 0.5 to 75 parts by weight, more preferably 1 to 50 parts by weight, still more preferably 7 to 35 parts by weight.

  If the ratio of the wholly aromatic liquid crystalline polyester to 100 parts by weight of the polybutylene terephthalate resin is less than 0.1 parts by weight, the weather resistance improvement effect may not be sufficiently obtained, and if it exceeds 100 parts by weight, the cost increases. The flexible mechanical properties such as flexibility and toughness of polybutylene terephthalate may be impaired.

  The polybutylene terephthalate resin composition of the present invention has a feature that the melting point of the wholly aromatic liquid crystal polyester to be blended is 250 ° C. or less, so that the wholly aromatic liquid crystal polyester is uniformly dispersed in the polybutylene terephthalate resin that is a matrix resin, It can be a resin composition having excellent weather resistance, which is the object of the present invention. Therefore, a compatibilizing agent is not particularly required for blending, but a compatibilizing agent may be added for the purpose of further improving the compatibility of the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester. Here, the compatibilizing agent means one having a function of localizing at the interface of each polymer phase constituting the blend polymer and reducing the interfacial tension between these phases.

  In the polybutylene terephthalate resin composition of the present invention, a weather resistance improver may be added for the purpose of further improving the weather resistance. In the present specification, the “weather resistance improver” has an ultraviolet ray absorbing action, a radical scavenging action, an antioxidant action, a light stabilizing action, etc., thereby improving the weather resistance of the material in which it is blended. Refers to a compound.

  Examples of the weather resistance improver include various types of compounds such as benzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzoate compounds, triazine compounds, hindered amine compounds, cinnamyl compounds, and the like. A property improving agent may be used individually or may be used in mixture of 2 or more types.

  Examples of benzophenone compounds include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octyloxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4. -Octadecyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2-hydroxy Examples include -4-methoxybenzophenone-5-sulfonic acid trihydrate, bis (2-hydroxy-3-benzoyl-6-methoxyphenyl) methane, and the like.

  Examples of the benzotriazole compounds include 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) -2H-benzotriazole. 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -2H-benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) -2H-benzotriazole, 2- (3 5-di-t-octyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (3,5-di-t-amyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (3-lauryl- 5-methyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) -5 Chloro-2H-benzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-bis (1-methyl-1-) Phenylethyl) -2-hydroxyphenyl) -2H-benzotriazole, bis (3- (2H-benzotriazol-2-yl) -2-hydroxy-5-methylphenyl) methane, bis (3- (2H-benzotriazole) -2-yl) -2-hydroxy-5- (1,1,3,3-tetramethylbutyl) phenyl) methane, bis (3- (2H-benzotriazol-2-yl) -2-hydroxy-5 Cumylphenyl) methane, bis (3- (2H-benzotriazol-2-yl) -2-hydroxy-5-octylphenyl) methane, 1,1-bis (3 (2H-benzotriazol-2-yl) -2-hydroxy-5-methylphenyl) octane, 1,1-bis (3- (2H-5-chlorobenzotriazol-2-yl) -2-hydroxy-5 Methylphenyl) octane, 1,2-ethanediylbis (3- (2H-benzotriazol-2-yl) -2-hydroxybenzoate), 1,12-dodecandiylbis (3- (2H-benzotriazol-2-yl) -4-hydroxybenzoate), 1,3-cyclohexanediylbis (3- (5-chloro-2H-benzotriazol-2-yl) -2-hydroxybenzoate), 1,4-butanediylbis (3- (2H-benzo) Triazol-2-yl) -4-hydroxy-5-methylphenylethanoate), 3,6-dioxa-1, 8-octanediylbis (3- (5-methoxy-2H-benzotriazol-2-yl) -4-hydroxyphenylethanoate), 1,6-hexanediylbis (3- (3- (2H-benzotriazole- 2-yl) -4-hydroxy-5-t-butylphenyl) propionate), p-xylenediylbis (3- (3- (2H-benzotriazol-2-yl) -4-hydroxyphenyl) propionate), bis (3- (2H-benzotriazol-2-yl) -4-hydroxytoluyl) malonate, bis (2- (3- (2H-benzotriazol-2-yl) -4-hydroxy-5-octylphenyl) ethyl) Terephthalate, bis (3- (2H-benzotriazol-2-yl) -4-hydroxy-5-propyltoluyl) o Tagioate, 2- (2H-benzotriazol-2-yl) -6-phthalimidomethyl-4-methylphenol, 2- (2H-benzotriazol-2-yl) -6-phthalimidoethyl-4-methylphenol, 2- (2H-benzotriazol-2-yl) -6-phthalimidooctyl-4-methylphenol, 2- (2H-benzotriazol-2-yl) -6-phthalimidomethyl-4-tert-butylphenol, 2- (2H- And benzotriazol-2-yl) -6-phthalimidomethyl-4-cumylphenol, 2- (2H-benzotriazol-2-yl) -4,6-bis (phthalimidomethyl) phenol, and the like.

  Examples of the salicylic acid ester compounds include phenylsulcylate, 2,4-ditertiary butylphenyl-3,5-ditertiary butyl-4-hydroxybenzoate, and the like.

  Examples of the benzoate compound include 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate.

  Examples of the triazine compound include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-hexyloxyphenol.

  Examples of hindered amine compounds include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, and bis (1 Octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6, -pentamethyl-4-piperidyl) -2- (3,5-di-t -Butyl-4-hydroxybenzyl) -2-n-butylmalonate, dimethyl succinate 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly ((6- (1,1,3,3-Tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl) ((2,2,6,6-tetramethyl-4-piperidyl ) Imino Hexamethylene ((2,2,6,6, -tetramethyl-4-piperidyl) imino)), N, N′-bis (3-aminopropyl) ethylenediamine · 2,4-bis (N-butyl-N—) (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -6-chloro-1,3,5-triazine condensate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) ) 1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate and the like.

  Other weather resistance improvers include, for example, 2-ethoxy-2′-ethyl-oxalic acid bisanilide, ethyl-2-cyano-3,3-diphenyl acrylate, 2-ethylhexyl-2-cyano-3,3-diphenyl. An acrylate etc. are mentioned.

  Of these, benzophenone-based, benzotriazole-based, salicylic acid ester-based, benzoate-based, triazine-based, and hindered amine-based compounds are preferable because they are compatible with the polybutylene terephthalate resin and have little influence on physical properties.

  When using a weather resistance improver, the blending amount of the weather resistance improver is preferably 0.01 to 5 parts by weight, more preferably 0.03 to 3 parts by weight with respect to 100 parts by weight of the polybutylene terephthalate resin. More preferably, it is 0.1 to 1 part by weight. If the blending amount of the weather resistance improver is less than 0.01 parts by weight, the weather resistance improving effect may not be exhibited. If it exceeds 5 parts by weight, the moldability and heat resistance of the polybutylene terephthalate resin composition will decrease. Tend.

  If necessary, the polybutylene terephthalate resin composition of the present invention may contain an inorganic filler and / or an organic filler.

  Examples of the inorganic filler and / or organic filler that may be blended in the polybutylene terephthalate resin composition of the present invention include glass fiber, silica alumina fiber, alumina fiber, carbon fiber, potassium titanate fiber, and aluminum borate. 1 or more types selected from the group consisting of fiber, aramid fiber, talc, mica, graphite, wollastonite, dolomite, clay, glass flake, glass beads, glass balloon, calcium carbonate, barium sulfate, and titanium oxide . In these, glass fiber is preferable at the point which the balance of a physical property and cost is excellent.

  When an inorganic filler and / or an organic filler is used, the blending amount of the filler is 0.1 to 200 parts by weight with respect to 100 parts by weight of the total amount of polybutylene terephthalate resin and wholly aromatic liquid crystal polyester. It is preferably 1 to 100 parts by weight, more preferably 5 to 50 parts by weight.

  In addition to the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester, other resin components and additives may be blended in the polybutylene terephthalate resin composition of the present invention as long as the object of the present invention is not impaired. Examples of other resin components include polyamide, polyester, polyacetal, polyphenylene ether, and modified products thereof, and thermoplastic resins such as polysulfone, polyethersulfone, polyetherimide, and polyamideimide, phenol resin, epoxy resin, and polyimide resin. And other thermosetting resins. Examples of the additive include particles, a flame retardant, and an antistatic agent.

  Other resin components and additives can be blended alone or in combination of two or more.

  When the other resin component is blended, the blending amount of the resin component is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the total amount of the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester. More preferably, it is 1 to 80 parts by weight.

  When the additive is blended, the blending amount of the additive is preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the total amount of the polybutylene terephthalate resin and the wholly aromatic liquid crystal polyester, More preferably, it is ˜3 parts by weight.

  The polybutylene terephthalate resin composition of the present invention comprises the above-mentioned polybutylene terephthalate resin and wholly aromatic liquid crystal polyester, if necessary, the above-mentioned compatibilizer, weather resistance improver, inorganic filler and / or organic filler, It can manufacture by melt-kneading with a kneader with a resin component and an additive. The compatibilizer, weather resistance improver, inorganic filler and / or organic filler, other resin components and additives may be blended in advance with either the polybutylene terephthalate resin or the wholly aromatic liquid crystal polyester, The polybutylene terephthalate resin composition may be blended when being molded.

  As the kneading machine, a Banbury mixer, a kneader, a single-screw or twin-screw extruder is used. For example, when a twin-screw extruder is used, kneading is performed with specific energy (extruder work amount per discharge amount (kW · h / kg)) of 0.1 to 0.25 while the vent port is evacuated. However, the present invention is not limited to this, and the kneading may be performed in an inert gas atmosphere.

  The polybutylene terephthalate resin composition of the present invention is melt-processed by a known molding method using an injection molding machine, an extruder, or the like, and can be made into products such as molded products, films and fibers. The polybutylene terephthalate resin composition of the present invention can be used for various applications such as mechanical parts, electrical / electronic parts, construction / civil engineering parts, household / office supplies, furniture parts and daily necessities, but has excellent weather resistance. Therefore, it can be suitably used for automobile parts, construction / civil engineering members and household items used outdoors.

  Hereinafter, although an example explains the present invention in detail, the present invention is not limited to this.

In the examples, the following abbreviations represent the following compounds:
PBT: polybutylene terephthalate resin LCP: wholly aromatic liquid crystal polyester PET: polyethylene terephthalate BON6: 6-hydroxy-2-naphthoic acid POB: parahydroxybenzoic acid
HQ: hydroquinone BP: 4,4′-dihydroxybiphenyl TPA: terephthalic acid NDA: 2,6-naphthalenedicarboxylic acid

(Polybutylene terephthalate resin)
In the examples, the following were used as polybutylene terephthalate resins.
PBT: Wintech Polymer Juranex 330LC

(Synthesis of LCP)
[Synthesis Example 1]
A reaction vessel equipped with a stirrer with a torque meter and a distillation tube was charged with BON6, POB, HQ and TPA so that the total amount was 5 mol in the composition ratio shown in Table 1, and then 0.05 g of potassium acetate (total monomer The acetic anhydride was charged in an amount of 1.025 times the molar amount of the total monomers and the hydroxyl amount (moles) of all monomers, and deacetic acid polymerization was carried out under the following conditions.

  In the polymerization, the temperature was raised from room temperature to 150 ° C. in 1 hour under a nitrogen gas atmosphere, and the temperature was maintained for 30 minutes. Next, while acetic acid produced as a by-product was distilled off, the temperature was quickly raised to 210 ° C. and kept at that temperature for 30 minutes. Thereafter, the temperature was raised to 335 ° C. over 3 hours, and then the pressure was reduced to 20 mmHg over 30 minutes. When the predetermined torque was exhibited, the polymerization reaction was terminated, and the reaction vessel contents were taken out and pulverized. LCP resin pellets LCP-1 were obtained. The amount of acetic acid distilled during the polymerization was almost as theoretical.

  The melting point of the obtained LCP-1 measured by DSC was 221 ° C.

[Synthesis Examples 2 to 4]
LCP-2 to LCP-4 were obtained based on Synthesis Example 1 except that the monomer composition was changed to the composition shown in Table 1. The melting points of the obtained LCPs are shown together in Table 1.

[Example 1]
30 parts by weight of glass fiber (100 parts by weight of polybutylene terephthalate resin and LCP-1 obtained in Synthesis Example 1 in the amount shown in Table 2) and 100 parts by weight of the total amount of polybutylene terephthalate resin and LCP-1 ( 3 mm long chopped strands) were dry blended and compounded at a processing temperature (cylinder temperature) shown in Table 2 using a twin screw extruder (manufactured by Nippon Steel Tuna Co., Ltd., TEX-30), and LCP-1 The pellets of the polybutylene terephthalate resin composition were blended. The obtained pellets were injection molded using an injection molding machine (PS40) manufactured by Nissei Plastic Industry Co., Ltd. under conditions of a molding temperature of 210 to 260 ° C. and a mold temperature of 70 ° C., and a bending test piece having a thickness of 6.4 mm. And 1.6 mm thick ASTM No. 1 dumbbells. The bending test piece was used to measure the size of sink marks, and the No. 1 dumbbell was used to measure the tensile strength and perform a weather resistance test. The results are shown in Table 2.

  The measurement of sink marks, the measurement of tensile strength, and the weather resistance test were performed by the methods described below.

(Measure sink marks)
Using the bending test piece, the maximum sink depth of the chuck portion was measured with a micrometer.

(Measurement of tensile strength and weather resistance test)
Using ASTM No. 1 dumbbell as a test piece, using a Super Xenon Weather Meter (SX-75) manufactured by Suga Test Instruments Co., Ltd., and processing up to 3000 hours under the following conditions in accordance with JIS K7350-2. A tensile test according to ASTM D638 was performed to measure the tensile strength, and the value was taken as the value after the weather resistance test. Moreover, the retention with respect to the initial value (value of tensile strength at a treatment time of 0 hour) was determined.

Test conditions:
Irradiance (300 to 400 nm): 60 W / m ²
Exposure cycle: 102 minutes irradiation, 18 minutes irradiation and water spraying Black panel temperature in the tank: 63 ° C
Temperature control inside the tank: None Relative humidity control: Available (50%)

[Examples 2 to 4 and Comparative Examples 1 to 4]
Except that the polybutylene terephthalate resin, LCP, and processing temperature were changed as shown in Table 2, a pellet of the polybutylene terephthalate resin composition was obtained in the same manner as in Example 1, and measurement of sink marks, measurement of tensile strength, and weather resistance were obtained. A sex test was performed. The results are shown in Table 2.

  As is apparent from Table 2, the polybutylene terephthalate resin composition of the present invention has significantly improved weather resistance while suppressing the occurrence of sink marks during molding as compared with a single polybutylene terephthalate resin. Met.

Claims (5)

Polybutylene terephthalate resin and wholly aromatic liquid crystal containing 100 mol parts of polybutylene terephthalate resin and having a repeating unit represented by formula [I] in an amount of 25 mol% or more of all repeating units and having a melting point of 250 ° C. or less. A polybutylene terephthalate resin composition containing 0.1 to 100 parts by weight of polyester.

Wholly aromatic liquid crystal polyester, wherein the following [I] ~ [IV] is formed using the repeating unit represented by claim 1, wherein the polybutylene terephthalate resin composition:

[In the formula, Ar ₁ and Ar ₂ each represent one or more divalent aromatic groups, and p, q, r, and s represent the composition ratio (mol%) in the wholly aromatic liquid crystal polyester of each repeating unit. And satisfies the following formula:
0.4 ≦ p / q ≦ 2.0
2 ≦ r ≦ 15, and 2 ≦ s ≦ 15]. The polybutylene terephthalate resin composition according to claim 2, wherein the composition ratio of the repeating units represented by the formulas [I] to [IV] satisfies the following formula:
35 ≦ p ≦ 48,
35 ≦ q ≦ 48,
2 ≦ r ≦ 15, and 2 ≦ s ≦ 15. Ar ₁ is

And / or

And
Ar ₂ is

And / or

Is,
The polybutylene terephthalate resin composition according to claim 2 or 3.   A molded article formed by injection molding the polybutylene terephthalate resin composition according to claim 1.