JP2009040840A - Thermoplastic polyester resin composition and molded resin article using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic polyester resin composition which is excellent in both flowability and mechanical properties which have been conventionally difficult, and also excellent in scratch resistance. <P>SOLUTION: Provided is the thermoplastic polyester resin composition comprising 100 pts.wt. of (a) a thermoplastic saturated polyester resin and 1 to 100 pts.wt. of (b) a thermosetting unsaturated polyester resin having a higher thermal deformation temperature than that of (a) the thermoplastic saturated polyester resin. A resin molded article prepared by molding the same is provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermoplastic saturated polyester resin composition and a resin molded body formed by molding the same. Specifically, the present invention relates to a thermoplastic saturated polyester resin composition excellent in all of fluidity, mechanical properties, hydrolysis resistance, and scratch resistance, and a resin molded body formed by molding the same.

  Thermoplastic polyester resins represented by polybutylene terephthalate resin (PBT resin) and polyethylene terephthalate resin (PET resin) are easy to process, and also have mechanical properties, electrical properties, heat resistance, and other physical and chemical properties. Excellent characteristics.

  Using this characteristic, from various automobile parts, electrical and electronic equipment circuit connection relays, switches, connectors, electrical and electronic equipment parts that require high reliability such as sensors, and other precision equipment parts, It is also used for bath and sanitary fields such as bathrooms, washstands and toilets. Among them, the PBT resin has a high crystallization speed, and is therefore suitably used for injection molding. In particular, it is widely used as a resin material for automobiles, electrical / electronic device parts, particularly connectors.

  Now, if the resin molded body formed by molding the thermoplastic saturated polyester resin composition is a thin resin part such as a connector, the metal terminal can be securely held with a lance, etc., and the connector lock can be loosened. There is no need for it. Many of these parts such as lances and lock mechanisms are thin and are often taken. For this purpose, these parts are usually formed by injection molding.

  At this time, in order to satisfy the required performance, the thermoplastic polyester resin composition which is a raw material resin (hereinafter sometimes simply referred to as “raw resin”) has sufficient fluidity, and the obtained resin The molded body is required to have sufficient rigidity and toughness.

  In general, when fluidity is imparted to a raw material resin, for example, a method of lowering the molecular weight of the raw material resin can be mentioned. On the other hand, however, the toughness of the resulting resin molding is reduced, and cracks are easily generated during molding. Also, reinforcing fillers such as talc are usually added for the purpose of imparting rigidity, but in this case as well, the tensile elongation and toughness are lowered against the improvement of the elastic modulus of the resin molded product, and the lance is reduced. And the lock mechanism was damaged.

  Further, if the surface of the resin molded body is scratched, the scratch becomes a crack starting point, and there is a risk of damage when the terminal is detached. As a method for improving toughness, a method of adding a polyester-based elastomer to a raw material resin has been proposed particularly when the component is a connector (see, for example, Patent Documents 1 and 2). However, this method inevitably reduces fluidity and rigidity, and it is difficult to satisfy mechanical properties, fluidity, and scratch resistance at the same time.

  In addition, as a cause of the lowering of the toughness of the raw material resin, for example, poor adhesion at the interface between the filler and the raw material resin is known. There has been proposed a method for improving the interfacial adhesive strength using a surface treated with a silane coupling agent having an epoxy group or the like (see, for example, Patent Document 3).

  However, even if such a surface treatment filler is used, there is a problem that both the elastic modulus and the toughness are not improved at the same time, although there is a slight physical property improvement effect of the raw material resin. In particular, in the production of a thin resin molded body such as a connector, the fluidity of the raw material resin is important. However, the raw material resin containing a filler treated with a reactive silane coupling agent tends to decrease in fluidity. There was a problem to say.

In addition, as a saturated polyester resin composition containing a thermosetting unsaturated polyester resin, the thing for the purpose of the surface hardness improvement of a saturated polyester resin is known, for example (refer patent document 4). However, the upper limit of the thermosetting unsaturated polyester resin content in the saturated polyester resin composition is as low as 10% by weight, and it has even been suggested to improve the scratch resistance and fluidity of the saturated polyester resin composition at the same time. There wasn't.
Japanese Patent Publication No. 3-50391 JP-A-9-255857 Japanese Patent Application Laid-Open No. 5-140429 JP-A-6-145487

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a thermoplastic polyester resin composition having not only excellent mechanical properties but also excellent fluidity and scratch resistance. is there.

  The present inventors have intensively studied to solve the above-described problems. As a result, a specific amount of a thermosetting resin is contained in the thermoplastic polyester resin, and preferably, a specific amount of a thermosetting resin having a higher thermal deformation temperature than that of the thermoplastic polyester resin is contained. It has been found that the thermoplastic polyester resin composition in which the resin is dispersed as fine particles in the thermoplastic polyester resin exhibits excellent fluidity.

  Furthermore, the resin molded body formed by molding this thermoplastic saturated polyester resin composition is excellent in mechanical properties such as toughness and rigidity, and also in scratch resistance, and has been considered difficult in the past. As a result, the present invention was completed.

  That is, the gist of the present invention is that (a) 100 parts by weight of the thermoplastic polyester resin contains 1 to 100 parts by weight of (b) a thermosetting resin whose thermal deformation temperature is higher than that of the (a) thermoplastic polyester resin. The thermoplastic polyester resin composition characterized by the above, and the resin molded product formed by molding the same.

  Among them, the thermoplastic saturated polyester resin composition of the present invention is excellent in fluidity, and the mechanical properties (rigidity and toughness) of the resulting resin molded article are excellent, so connectors for connecting electrical / electronic equipment circuits, etc. Not only can it be used for thin products, but it can also be used in bath and sanitary fields (washing bowls, bathtubs, toilet seats, tanks); components for septic tanks, automobiles, rail cars, ships, etc .; artificial marble suitable as a kitchen counter ; Electric parts such as cooking utensils panels and buttons; can be expected to be used for resin products that require high scratch resistance and high appearance. It can be expected to be manufactured by a molding method.

Hereinafter, the present invention will be described in detail.

<(A) Thermoplastic saturated polyester resin>
The (a) thermoplastic saturated polyester resin used in the present invention is a polyester resin in which the constituent components of the polyester main chain unit are an alcohol component and an acid component, the acid component is a dicarboxylic acid or a derivative thereof, and the alcohol component is a diol. Thus, the main acid component does not contain an unsaturated fatty acid. The thermoplastic saturated polyester resin (a) used in the present invention is not particularly limited as long as it is a thermoplastic saturated polyester resin, and any conventionally known one can be used. The thermoplastic saturated polyester resin (a) may be used alone or in combination of two or more in any proportion.

  The dicarboxylic acid or derivative thereof, which is a component of the thermoplastic saturated polyester resin used in the present invention (a), includes aromatic dicarboxylic acid, alicyclic dicarboxylic acid, aliphatic dicarboxylic acid, and lower alkyl or glycol thereof. Of these esters.

  Specific examples of aromatic dicarboxylic acids include phthalic acid, terephthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 4,4′-benzophenone dicarboxylic acid, 4 4,4'-diphenoxyethanedicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and esters thereof.

  Specific examples of the alicyclic dicarboxylic acid include 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, and the like. Specific examples of the aliphatic dicarboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid, and esters thereof.

  These dicarboxylic acids and derivatives thereof such as esters thereof may be used singly or in combination of two or more in any proportion. Among them, the acid component of the thermoplastic saturated polyester resin used in the present invention is preferably an aromatic dicarboxylic acid, a lower alkyl ester having 1 to 4 carbon atoms, or a glycol ester. Specifically, for example, terephthalic acid And its lower alkyl esters are particularly preferred.

 Specific examples of the diol that is a constituent component of the thermoplastic saturated polyester resin (a) used in the present invention include aliphatic diols, alicyclic diols, and aromatic diols.

  Among these aliphatic diols, aliphatic diols having 2 to 20 carbon atoms are preferable. Specifically, for example, ethylene glycol, 1,4-butanediol, diethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, polypropylene glycol, polytetramethylene glycol, dibutylene glycol, 1,5- Examples include pentanediol, neopentyl glycol, 1,6-hexanediol, and 1,8-octanediol.

  As the alicyclic diol, an alicyclic diol having 2 to 20 carbon atoms is particularly preferable. Specific examples include 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol, and the like.

  As the aromatic diol, an aromatic diol having 6 to 14 carbon atoms is particularly preferable. Specific examples include xylylene glycol, 4,4'-dihydroxybiphenyl, 2,2-bis (4-hydroxyphenyl) propane and bis (4-hydroxyphenyl) sulfone.

  These diols may be used alone or in combination of two or more in any proportion. Among them, the diol component of the thermoplastic saturated polyester resin (a) used in the present invention is preferably an aliphatic diol, particularly preferably ethylene glycol or 1,4 butanediol, and particularly preferably 1,4 butanediol.

  The (a) thermoplastic saturated polyester resin used in the present invention may have a hydroxycarboxylic acid, a monofunctional component, and / or a trifunctional or higher polyfunctional component. Specific examples of the hydroxycarboxylic acid include lactic acid, glycolic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 6-hydroxy-2-naphthalenecarboxylic acid, and p-β-hydroxyethoxybenzoic acid. A preferred example is given.

  Specific examples of monofunctional components include alkoxycarboxylic acid, stearyl alcohol, benzyl alcohol, stearic acid, benzoic acid, tert-butylbenzoic acid, and benzoylbenzoic acid.

  Preferred examples of the trifunctional or higher functional component include tricarballylic acid, trimellitic acid, trimesic acid, pyromellitic acid, gallic acid, trimethylolethane, trimethylolpropane, glycerol, and pentaerythritol.

  As the (a) thermoplastic saturated polyester resin used in the present invention, a polybutylene terephthalate resin (PBT resin) is particularly preferable. In the present invention, the PBT resin means that terephthalic acid accounts for 50 mol% or more of the total dicarboxylic acid component, and 1,4-butanediol accounts for 50 mol% or more of the total diol.

  As the PBT resin used in the present invention, the ratio of terephthalic acid in the dicarboxylic acid unit is preferably 70 mol% or more, particularly preferably 90 mol% or more, and the ratio of 1,4-butanediol in the diol unit is preferably It is preferably 70 mol% or more, particularly 90 mol% or more.

  In particular, the (a) thermoplastic saturated polyester resin used in the present invention is a polybutylene terephthalate homopolymer having terephthalic acid as the only dicarboxylic acid unit and 1,4-butanediol as the only diol unit. , Because mechanical properties and heat resistance are further improved.

  The terminal carboxyl group concentration of the PBT resin used in the present invention may be appropriately selected and determined. However, if it is too high, the hydrolysis resistance and fluidity tend to deteriorate, so it is usually 40 μeq / g or less. It is preferable that it is -35microeq / g, especially 5-30microeq / g.

  The terminal carboxyl group concentration was measured by dissolving 0.5 g of PBT resin in 25 ml of benzyl alcohol and titrating with a benzyl alcohol solution having a sodium hydroxide concentration of 0.01 mol / liter. The equivalent carboxyl group equivalent is shown.

  The intrinsic viscosity of the PBT resin used in the present invention may be appropriately selected and determined. However, if it is too low, the mechanical properties deteriorate, and conversely, if it is too high, the fluidity decreases and the molding process becomes difficult. There is a case. Therefore, it is usually 0.5 to 3.0 dl / g, preferably 0.5 to 1.5 dl / g, particularly preferably 0.6 to 1.3 dl / g. Here, the intrinsic viscosity is a value measured under a condition of 30 ° C. in a mixed solvent of tetrachloroethane and phenol of 1: 1 (weight ratio).

  Moreover, the PBT resin used for this invention is good also as PBT resin which uses the 2 or more types of different intrinsic viscosity together, and has the intrinsic viscosity mentioned above.

  The method for producing the thermoplastic saturated polyester resin (a) used in the present invention is arbitrary, and any conventionally known one can be used. Specifically, for example, in a method for producing a PBT resin comprising a terephthalic acid component and a 1,4-butanediol component, a direct polymerization method, a transesterification method, and the like can be given.

  The production method of the PBT resin in the direct polymerization method is a method in which terephthalic acid and 1,4-butanediol are directly esterified, and water is generated in the initial esterification reaction. In the transesterification method, dimethyl terephthalate or the like is used as a main raw material, and alcohol is generated by an initial transesterification reaction. Among these, the direct esterification reaction is preferable from the viewpoint of raw material cost.

  In addition, the (a) thermoplastic saturated polyester resin used in the present invention may be produced by either a batch method or a continuous method with respect to the raw material supply or the polymer discharge form. Furthermore, the initial esterification reaction or transesterification reaction is carried out in a continuous operation, and the subsequent polycondensation is carried out in a batch operation. What was obtained by the method of performing by continuous operation may be used.

  (A) When a polymerization catalyst is used in the production of the thermoplastic saturated polyester resin, it is preferable to use a titanium compound and a Group 1 and / or Group 2 metal compound as the polymerization catalyst. Specific examples of the titanium compound include titanium alcoholates, among which tetrabutyl titanate is preferable.

  Specific examples of the Group 1 and / or Group 2 metal compounds include compounds such as lithium, sodium, potassium, magnesium, and calcium from the viewpoint of handling and availability, and catalytic effects. A magnesium compound excellent in the color tone of the obtained PBT resin is preferable. Of the magnesium compounds, magnesium acetate is particularly preferred.

  These polymerization catalysts are usually supplied as a solution of water, 1,4-butanediol or the like. As a supply amount, it is preferable that the titanium compound is 10 ppm or more and 80 ppm or less, particularly 70 ppm or less in terms of each metal atom per theoretical yield of the PBT resin. Further, the Group 1 and / or Group 2 metal compound is preferably 1 ppm or more and 50 ppm or less, and particularly preferably 40 ppm or less.

<(B) Thermosetting resin>
The (b) thermosetting resin used in the present invention is a reactive resin that takes an insoluble and infusible three-dimensional network structure by causing a curing reaction due to intermolecular crosslinking by the action of heat and, if necessary, a catalyst. Specifically, for example, phenol resin, melamine resin, unsaturated polyester resin, urea resin, urethane resin, silicone resin, diallyl phthalate resin, epoxy resin, epoxy acrylate resin, alkyd resin, guanamine resin, silicon resin, fluorine resin, heat Examples thereof include a curable polyimide resin and a thermosetting polyamide resin.

  Generally, the heat resistance (thermal deformation temperature) of the cured product is good, but in the case of the present invention, it is important that the thermal deformation temperature is higher than that of (a) the thermoplastic polyester resin. As the (b) thermosetting resin used in the present invention, one or a combination of two or more kinds may be used in combination, and among them, a phenol resin and a melamine resin are preferable. Moreover, (b) thermosetting resin used for this invention may contain additives, such as various solvents, a crosslinking agent, a polymerization initiator, a viscosity regulator, a leveling agent, or an antifoamer, as needed. .

  The production method of the (b) thermosetting resin used in the present invention is not particularly limited, and any conventionally known method can be used. For example, typical thermosetting resins, including phenolic resin and melamine resin, are published in Chapter 4 of the book “Plastics and Functional Polymer Materials” (August 1, 2005, 2nd edition) published by the Industrial Research Institute Encyclopedia Publishing Center. Has a detailed description.

  In the thermoplastic polyester resin composition of the present invention, the weight ratio of (a) the thermoplastic polyester resin and (b) the thermosetting resin may be appropriately selected and determined, but (a) the thermoplastic polyester resin On the other hand, if the amount of (b) thermosetting resin is too small, the effect of addition becomes insufficient. On the other hand, if the amount is too large, the fluidity and impact resistance of the resulting resin composition may decrease.

  Therefore, the amount of (b) thermosetting resin is usually 1 to 100 parts by weight, preferably 2 to 90, particularly 5 to 80 parts by weight, based on 100 parts by weight of a) thermoplastic polyester resin.

<(C) Epoxy compound>
In the present invention, (c) an epoxy compound may be further contained. (C) Since the epoxy compound has reactivity and affinity for (a) a thermoplastic saturated polyester resin and (b) a thermosetting resin, the mechanical properties of the thermoplastic saturated polyester resin composition of the present invention. This is preferable because strength and hydrolysis resistance are improved.

  The (c) epoxy compound used in the present invention is not particularly limited and may be monofunctional, bifunctional or polyfunctional, and two or more of these may be used in combination. Of these, bifunctional or higher epoxy compounds, that is, compounds having two or more epoxy groups in one molecule are preferable. Moreover, it is preferable that the epoxy equivalent in (c) epoxy compound is 100-5000 g / eq, and it is especially preferable that it is 150-2000 g / eq.

  Specific examples of the (c) epoxy compound used in the present invention include, for example, a glycidyl ether type, a diglycidyl ether type, a polyfunctional glycidyl ether type, a glycidyl ester type, a diglycidyl ester type, a glycidyl amine type, and an alicyclic diepoxy compound. And glycidyl imide compounds.

  As glycidyl ether, methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether and allyl glycidyl ether are preferable.

  Diglycidyl ethers include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, brominated bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, biphenyl diglycidyl ether, naphthalene diglycidyl ether, neopentyl glycol diglycidyl ether Ethylene glycol diglycidyl ether, glycerin diglycidyl ether and propylene glycol diglycidyl ether are preferred.

  Examples of polyfunctional glycidyl ethers include phenol novolac type epoxy compounds, o-cresol novolac type epoxy compounds, bisphenol novolac type epoxy compounds, trishydroxymethane type (trifunctional) epoxy compounds, tetraphenolethane type (tetrafunctional) epoxy compounds, and the like. preferable.

  As the glycidyl ester, benzoic acid glycidyl ester and sorbic acid glycidyl ester are preferable. As the diglycidyl ester, adipic acid diglycidyl ester, terephthalic acid diglycidyl ester, orthophthalic acid diglycidyl ester and the like are preferable.

  As the glycidylamine, tetraglycidyldiaminodiphenylmethane and triglycidyl isocyanurate are preferable. As the alicyclic diepoxy compound, 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexylcarboxylate is preferable. As the glycidyl imide compound, N-glycidyl phthalimide is preferable.

  As the (c) epoxy compound used in the present invention, a glycidyl ether type is preferable, among which (1) bisphenol A diglycidyl ether obtained from the reaction of bisphenol A and epichlorohydrin, and (2) phenol novolak and epichloro. Phenol novolac type epoxy compounds obtained by reaction with hydrin, and (3) o-cresol novolac type epoxy compounds obtained by reaction of o-cresol and epichlorohydrin are preferred.

  The content of the epoxy compound (c) in the present invention may be selected and determined as appropriate. However, if it is too small, the effect of improving the mechanical properties is insufficient, and conversely, if too much, the hydrolysis of the resin is accelerated. However, the strength may decrease.

  Therefore, the content of (c) epoxy compound is usually 0.1 to 100 parts by weight, preferably 0.3 to 50 parts by weight, based on 100 parts by weight of (a) thermoplastic polyester resin.

<Reinforcing filler>
The thermoplastic saturated polyester resin composition of the present invention may contain a reinforcing filler as long as the effects of the present invention are not impaired. The reinforcing filler is not particularly limited, and any conventionally known fibrous, plate-like, granular, and mixtures thereof can be used.

  Specific examples of the fibrous material include glass fibers, carbon fibers, silica alumina fibers, zirconia fibers, boron fibers, boron nitride fibers, silicon nitride fibers, potassium titanate fibers, metal fibers and other inorganic fibers, aromatic polyamides. Examples thereof include organic fibers such as fibers and fluororesin fibers.

  Examples of the plate-like material include glass flakes, mica, and metal foil. Examples of the particulate material include glass beads, wollastonite, talc, clay, zeolite, kaolin, potassium titanate, barium sulfate, calcium carbonate, titanium oxide, silicon oxide, aluminum oxide, and magnesium hydroxide.

  As the reinforcing filler, glass, silicon oxide, and calcium silicate, which have high hardness and are relatively easily available, are preferable. Specifically, glass fiber, glass flake, glass bead, glass powder, silica, quartz, wollastonite and the like can be mentioned, and these may be used alone or in combination of two or more at any ratio. Of these, glass having a high Mohs hardness and having excellent adhesion to a polyester resin by surface treatment is preferable.

  As the reinforcing filler, glass, silicon oxide, and calcium silicate, which have high hardness and are relatively easily available, are preferable. Specifically, glass fiber, glass flake, glass bead, glass powder, silica, quartz, wollastonite and the like can be mentioned, and these may be used alone or in combination of two or more at any ratio. Of these, glass having a high Mohs hardness and having excellent adhesion to a polyester resin by surface treatment is preferable.

  In the thermoplastic saturated polyester resin composition of the present invention, when the mechanical strength is improved, it is preferable to use a fibrous material among the reinforcing fillers as described above, and the thermoplastic saturated polyester resin composition. When it is desired to improve the surface appearance of the resin molded body obtained by molding a product, it is preferable to use a plate-like product or a granular reinforcing filler.

  In the fibrous reinforcing filler, the average fiber diameter may be appropriately selected and determined, but is usually 1 to 100 μm, considering the improvement of the mechanical strength of the obtained resin molded body, among which 2 to 50 μm, Furthermore, it is preferable that it is 3-30 micrometers, especially 5-20 micrometers.

  The average fiber length may be determined by appropriately selecting the desired resin molded body and the physical properties of the resin composition constituting it. If the average fiber length is too short, the reinforcing effect becomes insufficient. Conversely, if the average fiber length is too long, melt-kneading with the thermoplastic polyester resin and moldability of the resin composition (fiber reinforced thermoplastic saturated polyester resin composition) are possible. Since it may fall, it is 0.1-20 mm normally, and it is preferable that it is 1-10 mm especially.

  The reinforcing filler is preferably (a) surface-treated in order to improve the affinity with the thermoplastic polyester resin and the interfacial adhesion, and to reduce the opacity caused by the formation of voids at the interface. There is no restriction | limiting in particular as a surface treating agent, A conventionally well-known arbitrary thing can be used, Specifically, a silane coupling agent, an epoxy resin, etc. are mentioned as a specific thing specifically, for example.

Examples of the silane coupling agent include amino silane, epoxy silane, allyl silane, and vinyl silane. Of these, aminosilanes are preferred. Preferred examples of the amino silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ- (2-aminoethyl) aminopropyltrimethoxysilane. The content of the silane coupling agent in the surface treatment agent is preferably 0.1 to 8% by weight, and more preferably 0.5 to 5% by weight.

  The epoxy resin is preferably a polyfunctional epoxy resin such as a phenol novolac epoxy resin and a cresol novolac epoxy resin. The content of the epoxy resin in the surface treatment agent may be appropriately selected and determined, but is usually 1 to 20% by weight, and preferably 2 to 10% by weight.

  Among these, as the surface treatment agent, it is preferable to use an amino-based silane coupling agent and a novolac type epoxy resin in combination. By using these in combination, the inorganic functional group of the amino silane coupling agent is on the reinforcing filler surface, the organic functional group of aminosilane is the glycidyl group of the epoxy resin, and the glycidyl group of the epoxy resin is on the polyester resin. Since each of the reactivity is high, the interfacial adhesion between the reinforcing filler and the epoxy resin is improved, and the mechanical properties and hydrolysis resistance of the thermoplastic saturated polyester resin composition of the present invention are improved, which is preferable.

  The surface treatment agent used for the reinforcing filler is within the range not departing from the gist of the present invention, and other Group 1 metal compound and / or Group 2 metal compound components such as urethane resin, acrylic resin, antistatic agent, A lubricant, a water repellent and the like may be contained.

  Any conventionally known surface treatment method can be used. Specifically, for example, a method in which surface treatment is performed in advance with a surface treatment agent, such as the methods described in JP-A Nos. 2001-172055 and 53-106749, and (a) a thermoplastic saturated polyester resin And (b) a method of performing surface treatment by adding an untreated reinforcing filler and a surface treatment agent at the time of melt kneading with a thermosetting unsaturated polyester resin.

  The adhesion amount of the surface treatment agent to the reinforcing filler may be appropriately selected and determined. However, if the amount is too small, the effect of improving the mechanical strength may be insufficient. We cannot expect improvement of effect with increase. Therefore, it is usually 0.01 to 5% by weight, and preferably 0.05 to 2% by weight.

<Other additives>
The resin composition of the present invention may contain other additives without departing from the spirit of the present invention. Specific examples include antioxidants, flame retardants, heat stabilizers, lubricants, mold release agents, catalyst deactivators, crystal nucleating agents, crystallization accelerators, and coloring agents.

  These additives can be added during or after the polymerization of the (a) thermoplastic saturated polyester resin. Furthermore, in order to impart desired performance to the (a) thermoplastic saturated polyester resin, an ultraviolet absorber, a weather resistance stabilizer, an antistatic agent, a foaming agent, a plasticizer, an impact resistance improving agent, and the like may be contained.

  The blending method after the polymerization of the above various additives and resins is not particularly limited, but a method of using a uniaxial or biaxial extruder having equipment capable of devolatilization from the vent port as a kneader is preferable. Each component including an additional component may be supplied to the kneader in a lump or sequentially. Moreover, you may mix the 2 or more types of component chosen from each component including an additional component previously. When blending the reinforcing filler, it is desirable to supply the reinforcing filler from the middle of the extruder in order to prevent the reinforcing filler from being crushed during kneading.

  Antioxidants have the effect of improving heat aging resistance and improving retention such as color tone, tensile strength, and elongation. Examples of the antioxidant include phenol-based antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants, and these may be used alone or in combination of two or more at any ratio. Content of antioxidant is 0.001-1.5 weight part with respect to 100 weight part of (a) thermoplastic polyester resin, and it is preferable that it is 0.03-1 weight part especially.

  Phenol-based antioxidants include, among others, hindered phenols (one or two carbon atoms adjacent to a carbon atom of an aromatic ring to which a phenolic hydroxyl group is bonded are substituted with a substituent having 4 or more carbon atoms). In addition, the substituent having 4 or more carbon atoms may be bonded to a carbon atom of the aromatic ring by a carbon-carbon bond, or may be bonded via an atom other than carbon.) The antioxidant is preferred. This is because hindered phenolic antioxidants are likely to be stable radicals and are preferred as radical trapping agents. The molecular weight of the hindered phenol antioxidant is usually 200 or more, preferably 500 or more, and the upper limit is usually 3000.

  Specific examples of the phenolic antioxidant include p-cyclohexylphenol, 3-t-butyl-4-methoxyphenol, 4,4′-isopropylidenediphenol, 1,1-bis (4-hydroxyphenyl). ) Non-hindered phenolic antioxidants such as cyclohexane, 2-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-p-cresol, 2,4,6-tri-t-butylphenol, 4-hydroxymethyl-2,6-di-t-butylphenol, styrenated phenol, 2,5-di-t-butylhydroquinone, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) Propionate, triethylene glycol bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propio 1,6-hexanediol bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-t-butyl- 4-hydroxyphenyl) propionate], 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (6-tert-butyl-4-ethylphenol), 2,2′- Methylenebis [4-methyl-6- (1,3,5-trimethylhexyl) phenol], 4,4′-methylenebis (2,6-di-t-butylphenol), 4,4′-butylidenebis (3-methyl-) 6-t-butylphenol), 2,6-bis (2-hydroxy-3-t-butyl-5-methylbenzyl) -4-methylphenol, 1,1,3-tris 2-methyl-4-hydroxy-5-tert-butylphenyl] butane, 1,3,5-trimethyl-2,4,6-tris [3,5-di-tert-butyl-4-hydroxybenzyl] benzene, Tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, tris [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, 4,4 '-Thiobis (3-methyl-6-tert-butylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), 4,4'-thiobis (2-methyl-6-tert-butylphenol) And hindered phenol antioxidants such as thiobis (β-naphthol).

  The content of the phenolic antioxidant may be appropriately selected and determined. However, if the amount of the antioxidant is too small, the effect of addition becomes insufficient. On the other hand, if the amount is too large, the oxidation heat stability may decrease. In some cases, resin decomposition may occur during melt-kneading. Therefore, usually, it is preferably 0.001 to 1.5 parts by weight, more preferably 0.03 to 1 part by weight, based on 100 parts by weight of (a) the thermoplastic polyester resin.

  Specific examples of the sulfur-based antioxidant include didodecylthiodipropionate, ditetradecylthiodipropionate, dioctadecylthiodipropionate, pentaerythritol tetrakis (3-dodecylthiopropionate), thiobis ( N-phenyl-β-naphthylamine), 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyldithiocarbamate, nickel isopropylxanthate, trilauryltrithiophosphite, etc. Can be mentioned.

  Peroxy radicals (RCOO.) Generated by the oxidation of polyester extract hydrogen atoms and become hydroperoxides to generate new radicals. Especially, what has a thioether structure is preferable in order to decompose | disassemble this hydroperoxide efficiently. Among them, didodecylthiodipropionate, ditetradecylthiodipropionate, dioctadecylthiodipropionate, and pentaerythritol tetrakis (3-dodecylthiopropionate) are preferable. The molecular weight of the sulfur-based antioxidant is usually 200 or more, preferably 500 or more, and the upper limit is usually 3000.

Among the phosphorus-based antioxidants, P (OR) ₃ (R represents an alkyl group, an alkylene group, an aryl group, or an arylene group, which may be the same or different, and any two Rs are bonded to each other. And may have a ring structure.) Those having a structure are preferred.

  Specific examples of phosphorus antioxidants include triphenyl phosphite, diphenyl decyl phosphite, phenyl diisodecyl phosphite, tri (nonylphenyl) phosphite, and bis (2,4-di-t-butylphenyl). Examples include pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, and the like.

  The content of the sulfur-based antioxidant and the phosphorus-based antioxidant in the thermoplastic saturated polyester resin composition of the present invention may be appropriately selected and determined. However, if it is too small, the effect of addition becomes insufficient, and conversely, Even if it is too much, the oxidation heat stability may be lowered, or the resin may be decomposed during melt-kneading. Therefore, it is usually 0.001 to 1.5 parts by weight with respect to 100 parts by weight of the thermoplastic polyester resin (a), preferably 0.03 to 1 part by weight.

  There is no restriction | limiting in particular as a flame retardant, A conventionally well-known arbitrary thing can be used. Specific examples include organic halogen compounds, antimony compounds, phosphorus compounds, other organic flame retardants, and inorganic flame retardants.

  Examples of the organic halogen compound include brominated polycarbonate, brominated epoxy resin, brominated phenoxy resin, brominated polyphenylene ether resin, brominated polystyrene resin, brominated bisphenol A, pentabromobenzyl polyacrylate and the like. Examples of the antimony compound include antimony trioxide, antimony pentoxide, and sodium antimonate. Examples of the phosphorus compound include phosphate ester, polyphosphoric acid, ammonium polyphosphate, and red phosphorus.

  In addition, specific examples of the organic flame retardant include nitrogen compounds such as melamine and cyanuric acid, and examples of the inorganic flame retardant include aluminum hydroxide, magnesium hydroxide, silicon compound, and boron compound.

  The content of these flame retardants may be appropriately selected and determined, but if it is too small, the effect of addition becomes insufficient, and conversely if too large, the mechanical strength of the resin molded body may be lowered. is there. Therefore, it is usually 0.1 to 50 parts by weight with respect to 100 parts by weight of (a) thermoplastic polyester resin.

  The thermoplastic polyester resin composition of the present invention may further contain another resin as long as the effects of the present invention are not impaired. Specifically, for example, polyethylene resin, polypropylene resin, polystyrene resin, polyacrylonitrile resin, polymethacrylate resin, acrylonitrile / butadiene / styrene resin (ABS resin), polycarbonate resin, polyamide resin, polyphenylene sulfide resin, polyacetal resin, polyphenylene A thermoplastic resin such as an oxide resin may be used.

  Moreover, these thermoplastic resins may use 2 or more types together in arbitrary ratios. The content of these resins is preferably 0.1 to 50 parts by weight with respect to 100 parts by weight of (a) the thermoplastic polyester resin.

<Method for producing thermoplastic polyester resin composition>
The thermoplastic polyester resin composition of the present invention can be obtained by kneading the above-described raw materials by any conventionally known resin kneading technique. Specifically, for example, (b) a thermosetting resin is conventionally known. (A) The method of kneading | mixing with a thermoplastic saturated polyester resin is mentioned by arbitrary resin kneading | mixing methods. Among these, (a) thermoplastic polyester resin and (b) thermosetting resin fine particles are melt-kneaded, (a) thermoplastic polyester resin is a continuous layer, and (b) thermosetting resin fine particles are dispersed layers. It is preferable that

  Thus, by dispersing (b) thermosetting resin fine particles in a specific amount or more in (a) thermoplastic polyester resin, the fine particles have flexibility that can be appropriately deformed when melted. Unlike the rigid filler, the shear rate field absorbs the shear stress. Further, at a high shear rate in the molding region, it is considered that the nonlinearity of the stress-shear rate becomes strong and the melt viscosity decreases, as in a general dispersion system.

  Further, the thermosetting unsaturated polyester resin fine particles have good affinity with the thermoplastic saturated polyester and have a cross-linked structure, so it is considered that the generated cracks are absorbed. From these effects, it is considered that the material exhibits excellent physical properties in both fluidity and mechanical properties, which has been considered difficult in the past.

  In the thermoplastic polyester resin composition of the present invention, it is important that (a) the particle diameter of the thermosetting resin fine particles (b) dispersed in the thermoplastic polyester resin is very small. The maximum particle size is 500 μm or less, preferably 300 μm or less, and particularly preferably 200 μm or less.

  However, if the particle size is too small, the specific surface area increases rapidly, and improvement in mechanical properties such as toughness is expected, but the fluidity improvement effect may be reduced. Therefore, the lower limit of the average particle diameter is usually 0.1 μm, and preferably 1 to 100 μm.

  Further, it is preferable that the particles have an amorphous shape or a higher sphericity because they are excellent in fluidity and dispersibility. It is preferable that the particle size distribution has a moderate distribution rather than a sharp distribution close to monodispersion because the fluidity is excellent. The porous fine particles are effective for improving the dispersibility of the liquid when, for example, a liquid additive is used in combination.

  The molding method of the thermoplastic polyester resin composition of the present invention is not particularly limited, and any conventionally known thermoplastic resin molding method can be applied. Specific examples include injection molding, hollow molding, extrusion molding, and press molding. In particular, the advantage of the present invention is remarkable by using resin molding by injection molding by taking advantage of good fluidity.

  The molding conditions for injection molding may be appropriately selected and determined. Usually, the resin temperature is 240 to 280 ° C., the injection pressure is 20 to 150 MPa, the mold temperature is 60 to 100 ° C., and the resin molding is obtained by injection molding. Is mentioned.

  The thermoplastic polyester resin composition of the present invention is particularly suitable for molded products having complicated shapes such as molded products having a weld portion and a hinge portion and insert molded products, and thin-walled molded products. Or it can be applied to automobile parts. As an application in which the effect of the present invention is particularly remarkable, a connector for electrical / electronic equipment circuit connection that is highly demanded in terms of tensile strength, impact characteristics, wet heat resistance (hydrolysis resistance), etc. A coil bobbin, a relay, a switch, etc. are mentioned.

  The connector according to the present invention uses a resin composition produced as described above and a housing molded by a conventionally known method such as injection molding. Such a housing can be molded by selecting as appropriate, such as the number and shape of poles for inserting connector terminals, the shape of the lock portion, the shape of the housing portion, etc. There is no particular limitation.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded.

[Various measurement methods]
(1) Fluidity (melt shear viscosity)
A capillary rheometer (Capillograph 1C manufactured by Toyo Seiki Seisakusho) was used, and the measurement was performed at a temperature of 270 ° C. and a shear rate of 6080 sec ⁻¹ . The smaller the value, the better the fluidity.

(2) Tensile strength, flexural modulus Using an injection molding machine (model SG-75MIII manufactured by Sumitomo Heavy Industries), Examples 1 to 5 in Table 1 and comparison at a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. Examples 1 to 3 ISO test pieces and ASTM test pieces made of the respective resin compositions were prepared, and the ISO test pieces were subjected to a tensile test according to ISO 527 and a bending test according to ISO 178.

(3) Load deflection test (thermal deformation temperature)
No. made by Yasuda Seiki Seisakusho Using the 148 HDPC heat distortion tester, a high load (1.82 MPa) load deflection (thermal deformation) test was performed on the above-described ASTM test piece in accordance with ASTM D648.

(4) Surface hardness (pencil hardness)
Evaluation was performed according to JIS K5400 using a pencil hardness tester (manufactured by Toyo Seiki Seisakusho).

(5) Hydrolysis resistance The above-mentioned ISO test piece is saturated in steam at a temperature of 121 ° C. at a pressure of 203 kPa. When the ISO test piece does not contain a reinforcing filler, it is 60 hours, and when it contains a reinforcing filler, 100 hours. Wet heat treatment. The tensile strength of the ISO test pieces before and after the treatment was measured according to ISO 527.

Further, the tensile strength retention was determined according to the following formula.
Tensile strength retention (%) = (Tensile strength after treatment / Tensile strength before treatment) × 100

[Raw material of resin composition]
(A) Thermoplastic saturated polyester resin (a1) Polybutylene terephthalate resin: NOVADURAN (registered trademark) 5008 manufactured by Mitsubishi Engineering Plastics, intrinsic viscosity [η] = 0.85 dl / g Thermal deformation temperature (ASTM D648) 60 ° C.

(A2) Polybutylene terephthalate resin: Novaduran (registered trademark) 5020 manufactured by Mitsubishi Engineering Plastics, intrinsic viscosity [η] = 1.20 dl / g Heat distortion temperature (ASTM D648) 60 ° C.

(B) Thermosetting resin (b1) Phenol resin: P-120A manufactured by Otsuchi Sangyo Co., Ltd., particle diameter of 200 μm or less, heat distortion temperature (ASTM D648) 120 ° C.

  (B2) Melamine resin: M-120A manufactured by Taiho Sangyo Co., Ltd., particle diameter of 200 μm or less, heat distortion temperature (ASTM D648) 148 ° C.

  (C) Epoxy compound: o-cresol novolac type epoxy compound YDCN-704, epoxy equivalent 195 to 220 g / eq, manufactured by Tohto Kasei Co., Ltd.

  Reinforcing filler: Chopped strand glass fiber to which a surface treatment agent containing no novolak type epoxy resin is attached ECS03T-187 manufactured by Nippon Electric Glass Co., Ltd., average fiber diameter 13 μm, average fiber length 3 mm, Mohs hardness 6.5

  Antioxidant: Pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], Irganox 1010 manufactured by Ciba Specialty Chemicals

[Examples 1-5, Comparative Examples 1-3]
The ratio (weight) of the polybutylene terephthalate resin of (a1) and / or (a2), (b) thermosetting resin, (c) epoxy resin, reinforcing filler (glass fiber), and antioxidant Part) and mixed with a tumbler for 20 minutes.

  The ratio (parts by weight) of (b), (c), the reinforcing filler and the antioxidant was the ratio when the total weight of (a1) and (a2) was 100. The obtained raw material mixture was supplied to a hopper and melt-kneaded using a twin-screw extruder having a cylinder temperature of 250 ° C. (TEX30C manufactured by Nippon Steel Works, barrel 9 block configuration). When the glass fiber was blended, it was supplied from the fifth block counted from the hopper by the side feed method and melt-kneaded. The evaluation mentioned above was performed using the obtained resin composition. The evaluation results are shown in Table 1.

  As is apparent from Table 1, the thermoplastic polyester resin composition of the present invention has a low melt viscosity and is excellent in fluidity. In addition, it can be seen from the evaluation of the obtained resin molded product that it has excellent surface hardness and strength.

  On the other hand, the surface hardness is not improved in the resin composition containing no thermosetting resin as in Comparative Examples 1 and 2, and the hardness is not limited even if a reinforcing filler such as a glass filler is contained as in Comparative Example 3. Although improved, the melt viscosity also rises and the fluidity is lowered, so that it is not suitable for injection molding or the like.

Claims (7)

(A) Thermoplastic polyester characterized by containing 1 to 100 parts by weight of a thermosetting resin having a higher thermal deformation temperature than (a) the thermoplastic polyester resin with respect to 100 parts by weight of the thermoplastic polyester resin. Resin composition. (B) Thermosetting resin is a phenol resin or a melamine resin, The thermoplastic polyester resin composition of Claim 1 characterized by the above-mentioned. Furthermore, 0.1-100 weight part of (c) epoxy resins are contained, The thermoplastic polyester resin composition of Claim 1 or 2 characterized by the above-mentioned. The thermoplastic polyester resin composition according to any one of claims 1 to 3, wherein (a) the thermoplastic polyester resin is an aromatic polyester resin. The thermoplastic polyester resin composition according to any one of claims 1 to 4, wherein (b) the thermosetting resin is particles having an average particle diameter of 500 µm or less. The resin molding formed by shape | molding the thermoplastic polyester resin composition in any one of Claims 1-5. The resin molded body according to claim 6, which is a connector for electrical / electronic equipment circuit connection.