JP2007186629A - Polytrimethylene terephthalate resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polytrimethylene terephthalate resin composition having a short molding cycle, remarkably improving flashes during molding, having excellent melt retention stability and suitable for applications such as automotive parts or electrical/electronic parts. <P>SOLUTION: The polytrimethylene terephthalate resin composition comprises (A) 100 pts.wt. of a polytrimethylene terephthalate resin and (B) 0.01-10 pts.wt. of a styrene copolymer containing epoxy groups and having 0.1-10 meq/g epoxy number. The resin composition preferably has &ge;175&deg;C crystallization temperature (Tc) when the temperature of the resin composition is made to fall from a molten state at 270&deg;C by using a DSC (differential scanning calorimeter) and the weight-average molecular weight of the component (B) is preferably 500-50,000. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a polytrimethylene terephthalate resin composition having a short molding cycle and greatly improved burr during molding and toughness of a molded product.

  Thermoplastic polyesters typified by polytrimethylene terephthalate are excellent in mechanical properties, heat resistance, chemical resistance, weather resistance, and electrical properties, and are used in a wide range of fields such as automobile parts and electrical / electronic parts. With the expansion and diversification of applications, more advanced performance, easy moldability for complex shapes, and the like are often required. In general, when a large molded product or a thin molded product having a long flow length is injection molded, an operation such as increasing the injection pressure is often performed. At this time, a phenomenon that the resin leaks (burr) into a part of the mold becomes a problem, and a non-defective product may not be obtained. In particular, polytrimethylene terephthalate has a problem that the crystallization rate is slow, the burr phenomenon is remarkable, and the molding cycle is also slow.

In order to solve the above problems, for example, a method of adding a crystal nucleating agent to a thermoplastic polyester resin has been disclosed (see Patent Documents 1 and 2). However, even if these methods are used, the crystallization rate of polytrimethylene terephthalate does not increase, and the nucleating agent effect is poor. Therefore, the molding cycle cannot be shortened, and the burr phenomenon during molding is hardly improved.
Also disclosed is a method of increasing the crystallization rate by adding an ionomer to polytrimethylene terephthalate (see Patent Document 3). Certainly, in these methods, the crystallization speed is increased, but the ionomer is basic, so that the molecular weight of polytrimethylene terephthalate during the molding is greatly reduced and the molded product becomes brittle. In particular, when the molded product is enlarged, there is a problem that it cannot be used because the melt residence time becomes longer.

Japanese Patent Laid-Open No. 11-54189 Japanese Patent Laid-Open No. 11-286596 JP 2003-327806 A

  The present invention is a polytrimethylene terephthalate resin composition that does not have the above-mentioned problems, that is, has a short molding cycle, greatly improves burrs during molding, and has excellent melt retention stability. The purpose is to provide.

As a result of intensive studies to solve the above-mentioned problems, the present inventor has included a specific amount of styrene copolymer resin with respect to the polytrimethylene terephthalate resin, whereby the resin composition has a short molding cycle and is molded. As a result, the present inventors found that the burr at the time was improved and the melt residence stability was excellent.
That is, the present invention is a polytrimethylene terephthalate resin composition and a molded article using the same as described below.

(1) 0.01 to 10 parts by weight of (B) a styrene copolymer containing an epoxy group having an epoxy value of 0.1 to 10 meq / g, based on 100 parts by weight of (A) polytrimethylene terephthalate, Polytrimethylene terephthalate resin composition.
(2) The polytrimethylene terephthalate resin composition according to (1), wherein the component (B) has a weight average molecular weight of 500 to 50,000.
(3) The crystallization temperature (Tc) when the temperature is lowered from a molten state of 270 ° C. using a differential scanning calorimeter (DSC) is 175 ° C. or higher (1) or (2) ) Polytrimethylene terephthalate resin composition.
(4) The polytrimethylene terephthalate according to any one of (1) to (3), wherein the blending amount of the component (B) is 0.3 to 3 parts by weight with respect to 100 parts by weight of the component (A). Resin composition.
(5) A molded article comprising the polytrimethylene terephthalate resin composition according to any one of (1) to (4).
(6) An automobile part comprising the polytrimethylene terephthalate resin composition according to any one of (1) to (4).
(7) An electrical / electronic component comprising the polytrimethylene terephthalate resin composition according to any one of (1) to (4).

  The polytrimethylene terephthalate resin composition of the present invention has the effect that the molding cycle is short, the burrs during molding are greatly improved, and the melt retention stability is excellent.

The present invention will be specifically described below.
In the present invention, (A) polytrimethylene terephthalate (hereinafter sometimes abbreviated as PTT) refers to a polyester polymer using terephthalic acid as the acid component and trimethylene glycol as the glycol component. In the present invention, as trimethylene glycol, at least one selected from the group consisting of 1,3-propanediol, 1,2-propanediol, 1,1-propanediol and 2,2-propanediol is used. Among these, 1,3-propanediol is particularly preferable from the viewpoint of stability.

In addition, as long as the object of the present invention is not impaired, an aromatic dicarboxylic acid other than terephthalic acid, for example, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, Diphenoxyethane dicarboxylic acid, diphenylmethane dicarboxylic acid, diphenyl ketone dicarboxylic acid, diphenyl sulfone dicarboxylic acid, etc .; aliphatic dicarboxylic acids such as succinic acid, adipic acid, and sebacic acid; alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid; ε-oxy Copolymerization can be carried out using a part of oxydicarboxylic acid such as caproic acid, hydroxybenzoic acid, hydroxyethoxybenzoic acid and the like. In addition, ethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, neopentyl glycol, cyclohexane dimethanol, xylylene glycol, diethylene glycol, polyoxyalkylene glycol, hydroquinone, etc. are partially used as the glycol component. Can be copolymerized.
The amount of the copolymer component in the copolymerization is not particularly limited as long as it does not impair the object of the present invention, but it is usually 20 mol% or less of the acid component or 20 mol% or less of the glycol component. preferable.

  In addition, the above-described polyester component may be added to a branched component such as tricarbaric acid, trimesic acid, trimellitic acid, or other trifunctional or tetrafunctional ester-forming acid, or glycerin, trimethylolpropane, pentaerythritol, or the like. An alcohol having a functional or tetrafunctional ester-forming ability may be copolymerized. In that case, they may be 1.0 mol% or less, preferably 0.5 mol% or less, more preferably 0.3 mol% or less of the total dicarboxylic acid component.

The PTT of the present invention includes a case where two or more of these copolymer components are used in combination.
The manufacturing method of PTT used for this invention is not specifically limited. For example, it can be produced by the methods described in JP-A Nos. 51-140992, 5-262862, and 8-311177. As an example, terephthalic acid or an ester-forming derivative thereof (for example, a lower alkyl ester such as dimethyl ester or monomethyl ester) is reacted with trimethylene glycol or an ester-forming derivative thereof at a suitable temperature and time in the presence of a catalyst. And a method of subjecting the resulting terephthalic acid glycol ester to a polycondensation reaction in the presence of a catalyst at a suitable temperature and time to a desired degree of polymerization.

The intrinsic viscosity [η] of the PTT used in the present invention is preferably 0.60 dl / g to 2.00 dl / g from the viewpoint of mechanical properties and residence stability of a molded body obtained from the resin composition, and [η ] Is more preferably 0.80 dl / g to 1.50 dl / g, [η] is more preferably 0.90 dl / g to 1.40 dl / g, and [η] is 1.00 dl / g. Most preferably, it is g-1.30 dl / g.
The intrinsic viscosity [η] of PTT was measured using an Ostwald viscometer, and the ratio η _sp / C between the specific viscosity η _sp and the concentration C (g / 100 ml) in o-chlorophenol was 35 ° C. It can be calculated by the following equation (1).

  Further, the present invention provides various additives such as pH adjusters, antifoaming agents, color modifiers, flame retardants, antioxidants, ultraviolet absorbers, infrared absorbers, crystal nucleating agents as required for PTT. In addition, a case where a fluorescent whitening agent, a matting agent, or the like is copolymerized or mixed is also included.

Next, the styrene copolymer containing an epoxy group having an epoxy value of 0.1 to 10 meq / g, which is the component (B) of the present invention, will be described.
The styrene copolymer can be obtained by copolymerizing a vinyl monomer having an epoxy group and styrene. As the vinyl monomer having an epoxy group, glycidyl (meth) acrylate, (meth) acrylic acid ester having a cyclohexene oxide structure, (meth) allyl glycidyl ether, or the like can be used. Preferred is glycidyl (meth) acrylate.

The styrene copolymer having an epoxy group may be used in combination with any other vinyl monomer other than styrene that does not have any epoxy group as long as the effects of the present invention are not impaired.
Other vinyl monomers include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth ) (Meth) acrylic acid alkyl ester, (meth) acrylic acid polyalkylene glycol ester, (meth) having an alkyl group having 1 to 22 carbon atoms such as cyclohexyl acrylate (the alkyl group may be linear or branched) Alkoxyalkyl esters of acrylic acid, hydroxyalkyl esters of (meth) acrylic acid, dialkylaminoalkyl esters of (meth) acrylic acid, benzyl esters of (meth) acrylic acid, phenoxyalkyl esters of (meth) acrylic acid, isobornyl (meth) acrylate Esters, (meth) acrylic acid al Silyl alkyl ester and the like. Others include maleic anhydride, fumaric acid, (meth) acrylamide, (meth) acryldialkylamide, vinyl esters such as vinyl acetate, vinyl ethers, (meth) allyl ethers, aromatics such as styrene and α-methylstyrene. An α-olefin monomer such as a vinyl monomer, ethylene, or propylene can be used. These can use 1 type, or 2 or more types.

The viewpoint that the styrene copolymer having an epoxy group contains 5 to 95% by weight of a styrene unit and 95 to 5% by weight of a vinyl monomer unit having an epoxy group increases the crystallization speed of polytrimethylene terephthalate. It is more preferable to contain 10 to 90% by weight of styrene units, 5 to 70% by weight of vinyl monomer units having an epoxy group, and 0 to 85% by weight of other vinyl monomer units. Most preferably, it contains -80 wt%, 10-50 wt% of vinyl monomer units having an epoxy group, and 0-60 wt% of other vinyl monomer units.
The styrene copolymer having an epoxy group can be prepared by a normal radical polymerization method using a continuous tube process or a continuous stirred tank process in solution polymerization, emulsion polymerization, bulk polymerization, dispersion polymerization, or suspension polymerization.

The epoxy value of the styrene copolymer needs to be 0.1 to 10 meq / g, more preferably 0.5 to 5 meq / g, from the viewpoint of the melt residence stability of the resin composition. 1.0 to 3 meq / g is most preferable.
The weight average molecular weight of the styrene copolymer is preferably 500 to 50,000, more preferably 2000 to 30000, and more preferably 4000 to 20000 from the viewpoint of melt residence stability of the resin composition. Most preferred.
Furthermore, the glass transition temperature of the styrene copolymer is preferably 20 ° C. or higher, more preferably 40 ° C. or higher, from the viewpoint of MD (mold deposit) when molding the resin composition.

  From the viewpoint of crystallization speed, the resin composition of the present invention comprises (B) styrene copolymer containing an epoxy group having an epoxy value of 0.1 to 10 meq / g with respect to 100 parts by weight of (A) polytrimethylene terephthalate. It is necessary to blend 0.01 to 10 parts by weight of the coalescence, more preferably 0.1 to 5 parts by weight, and most preferably 0.3 to 3 parts by weight.

  The resin composition of the present invention has a crystallization temperature when the temperature is lowered from a molten state at 270 ° C. using a differential scanning calorimeter (DSC) from the viewpoint of burrs and molding cycles during molding. (Tc) is preferably 175 ° C. or higher, and most preferably 180 ° C. or higher.

  Further, when the resin composition of the present invention is further blended with 1 to 150 parts by weight of (D) inorganic filler with respect to 100 parts by weight as the total of (A) and (B), the composition more suitable for the purpose. Is obtained. Specific examples of the inorganic filler include glass fiber, carbon fiber, metal fiber, aramid fiber, asbestos, potassium titanate whisker, aluminum borate whisker, wollastonite, talc, glass flake, and glass beads. In particular, glass fiber and wollastonite are preferable. The type of glass fiber is not particularly limited as long as it is generally used for reinforcing resin, and can be selected from long fiber type, short fiber type chopped strands, milled fiber, and the like.

  When (E) a moldability improving agent is further added to the resin composition or resin molded body of the present invention, a resin composition or resin molded body more suitable for the purpose of the present invention (improving molding cycle) can be obtained. (E) Moldability improvers include higher fatty acids, higher fatty acid metal salts, higher fatty acid esters, higher fatty acid amide compounds, polyalkylene glycols or terminal modified products thereof, low molecular weight polyethylene or oxidized low molecular weight polyethylenes, Examples thereof include substituted benzylidene sorbitols, polysiloxanes, and caprolactones. Particularly preferred are (x) higher fatty acids, (y) higher fatty acid metal salts, and (z) higher fatty acid esters. Hereinafter, these (E) moldability improving agents will be described in detail.

(X) Higher fatty acids As the higher fatty acids, higher saturated fatty acids, higher unsaturated fatty acids or mixtures thereof are preferably used.
(X-1) Higher saturated fatty acids Higher fatty saturated fatty acids are, for example, capric acid, uradecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, Examples thereof include behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melissic acid, and laccelic acid, and mixtures thereof.

(X-2) Higher unsaturated fatty acids As the higher unsaturated fatty acids, unsaturated fatty acids having 6 to 22 carbon atoms are preferably used. Among them, more preferable examples include undecylenic acid, oleic acid, and elaidic acid. , Cetoleic acid, erucic acid, brassic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, stearolic acid, 2-hexadecenoic acid, 7-hexadecenoic acid, 9-hexadecenoic acid, gadoleic acid, gadoelasinic acid, 11-eicosene An acid etc. or a mixture thereof can be mentioned.

(Y) Higher fatty acid metal salts As the higher fatty acid metal salts, higher saturated fatty acid metal salts, higher unsaturated fatty acid metal salts, or mixtures thereof are preferably used.
(Y-1) Higher saturated fatty acid metal salts The higher fat saturated fatty acids are represented by the following general formula.
_{CH 3 (CH 2) n COO} (M)
Here, n = 8 to 30, and the metal element (M) is preferably 1A, 2A, 3A group element, zinc, aluminum or the like of the periodic table.
Among these, more preferred are, for example, capric acid, uradecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid , Heptacosanoic acid, montanic acid, mellicic acid, lithium salt of lactic acid, sodium salt, magnesium salt, calcium salt, zinc salt, aluminum salt, etc., or a mixture thereof.

(Y-2) Higher unsaturated fatty acid metal salts As higher unsaturated fatty acid metal salts, unsaturated fatty acids having 6 to 22 carbon atoms, elements 1A, 2A and 3A of the periodic table, zinc, aluminum and the like Of these, the metal salts of these are preferably used. 2-hexadecenoic acid, 7-hexadecenoic acid, 9-hexadecenoic acid, gadoleic acid, gadoelaidic acid, lithium salt of 11-eicosenoic acid, sodium salt, magnesium salt, calcium salt, zinc salt, aluminum salt, etc., or a mixture thereof Can be mentioned.

(Z) Higher fatty acid esters As the higher fatty acid esters in the present invention, an ester of a higher alcohol and a higher fatty acid, an ester of a polyhydric alcohol and a higher fatty acid, or a mixture thereof is preferably used.

(Z-1) Esters of higher alcohols and higher fatty acids As esters of higher alcohols and higher fatty acids, preferred are esters of aliphatic alcohols having 8 or more carbon atoms and higher fatty acids having 8 or more carbon atoms. is there. Preferred higher fatty acid esters include, for example, lauryl laurate, lauryl myristate, lauryl palmitate, lauryl stearate, lauryl behenate, lauryl lignocerate, lauryl meristate, myristyl laurate, myristyl myristate, myristyl stearate. , Myristyl behenate, myristyl lignocerate, myristyl melysate, palmityl laurate, palmityl myristate, palmityl stearate, palmityl behenate, palmityl lignocerate, palmityl meristate, stearyl laurate , Stearyl myristate, stearyl palmitate, stearyl stearate, stearyl behenate, stearyl arachinate, stearyl lignocerate, stearyl melicate, eye Syl laurate, eicosyl palmitate, eicosyl stearate, eicosyl behenate, eicosyl lignocerate, eicosyl meristate, behenyl laurate, behenyl myristate, behenyl palmitate, behenyl stearate, behenyl behenate, behenyl Arachinate, behenyl merisate, tetracosanyl laurate, tetracosapalmitate, tetracosanyl stearate, tetracosanyl behenate, tetracosanyl lignocerate, tetracosanyl serotete, serotinyl stearate, Mention may be made of serotinyl behenate, serotinyl serotinate, merisyl laurate, merisyl stearate, merisyl behenate, merisyl meristate, etc., or mixtures thereof.

(Z-2) Esters of polyhydric alcohol and higher fatty acid Partial esters of polyhydric alcohol and higher fatty acid are, for example, glycerin, 1,2,3-butanetriol, 1,2,3- Pentanetriol, erythritol, pentaerythritol, trimethylolpropane, mannitol, sorbitol and the like are preferably used.
Examples of higher fatty acids include capric acid, uradecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosane Acid, montanic acid, melissic acid, laccelic acid and the like are preferably used.

  Esters of these polyhydric alcohols and higher fatty acids may be monoesters, diesters or triesters. More preferred examples include higher fatty acid monoglycerides such as glycerin monolaurate, glycerin monomyristate, glycerin monostearate, glycerin monobehenate, glycerin monolignocerate, glycerin monomellate, pentaerythritol mono- or di- Laurate, pentaerythritol mono- or di-laurate, pentaerythritol mono- or di-myristate, pentaerythritol mono- or di-palmitate, pentaerythritol mono- or di-stearate, pentaerythritol mono- or Mono- or di-higher fats of pentaerythritol, such as di-behenate, pentaerythritol mono- or di-lignocerate, pentaerythritol mono- or di-melissate Esters, trimethylolpropane-mono- or di-laurate, trimethylolpropane-mono- or dimyristate, trimethylolpropane-mono- or dipalmitate, trimethylolpropane-mono- or di-stearate, trimethylol Mention may be made of mono- or di-higher fatty acid esters of trimethylolpropane, such as propane-mono- or di-behenate, trimethylolpropane-mono- or di-lignocerate, trimethylolpropane-mono- or di-melisate.

  And sorbitan-mono, di- or tri-laurate, sorbitan-mono, di- or tri-myristate, sorbitan-mono, di- or tri-stearate, sorbitan-mono, di- or tri-behenate, sorbitan-mono, di- or Sorbitan-mono, di- or tri-higher fatty acid esters such as tri-lignocerate, sorbitan-mono, di- or tri-melisate, mannitan-mono, di- or tri-laurate, mannitan-mono, di- or tri-myristate, mannitan- Mono-, di- or tri-palmitate, mannitan-mono, di- or tri-stearate, mannitan-mono, di- or tri-behenate, mannitan-mono, di- or tri-lignocerate, mannitan-mono, di- or tri-meliselate, etc. Mannita - it can be mentioned higher fatty acid esters, or mixtures thereof - mono-, di- or tri.

  The blending amounts of these (x) higher fatty acids, (y) higher fatty acid metal salts, and (z) higher fatty acid esters are the PTT100 in the thermoplastic resin composition of the present invention from the viewpoint of the molding cycle of the resin composition. It is preferable that it is 0.001-5 weight part with respect to a weight part, More preferably, it is 0.01-3 weight part.

  In the resin composition of the present invention, other resins or additives, for example, impact modifiers, pH adjusters, antioxidants, flame retardants, plasticizers, and the like as long as the characteristics and effects of the present invention are not impaired. Flame retardant aids, weather resistance (light) improvers, slip agents, various colorants and the like may be added.

Since the resin composition of the present invention has a high crystallization rate and excellent melt residence stability, it can be easily molded by various molding methods. Examples of the molding method include press molding, injection molding, gas-assisted injection molding, injection compression molding, welding molding, extrusion molding, blow molding, film molding, hollow molding, multilayer molding, foam molding, etc., but particularly injection molding. Is preferably used.
Since the resin composition of the present invention has a high crystallization rate and excellent melt residence stability, it can be widely used for various moldings from small high cycle molding to large molding with a long residence time. In particular, the resin composition of the present invention can be suitably used as an electric / electronic component that requires high cycle moldability or an automobile component that requires large moldability.

  The effects of the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. In addition, the used thermoplastic resin and its compounding agent are as follows.

(A) Polytrimethylene terephthalate (A1) Polytrimethylene terephthalate resin.
Polytrimethylene terephthalate having intrinsic viscosity [η] = 1.00 (dl / g) The intrinsic viscosity [η] of PTT was determined using an Ostwald viscometer at 35 ° C. and a specific viscosity η _sp in o-chlorophenol. And the ratio η _sp / C of the concentration C (g / 100 ml) was extrapolated to a concentration of zero and obtained by the following equation (1).

(A2) Polytrimethylene terephthalate resin Polytrimethylene terephthalate having intrinsic viscosity [η] = 1.10 (dl / g) (A3) Polytrimethylene terephthalate resin Intrinsic viscosity [η] = 1.30 (dl / g) Polytrimethylene terephthalate

(B) Styrene copolymer containing epoxy group having an epoxy value of 0.1 to 10 meq / g (B1) acrylic styrene copolymer; ARUFON UG-4030, manufactured by Toagosei Co., Ltd. Epoxy value: 1.8 meq / g ( (According to ASTM D-1652-73)
Weight average molecular weight: 11,000 (polystyrene conversion value determined from gel permeation chromatograph (GPC))
(B2) acrylic styrene copolymer; ARUFON UG-4040, manufactured by Toagosei Co., Ltd. Epoxy value: 2.1 meq / g (according to ASTM D-1652-73)
Weight average molecular weight: 9200 (polystyrene conversion value determined from gel permeation chromatograph (GPC))
(B3) Acrylic styrene copolymer; ARUFON UG-4000, manufactured by Toagosei Co., Ltd. Epoxy value: 0.7 meq / g (conforms to ASTM D-1652-73)
Weight average molecular weight: 3100 (polystyrene conversion value determined from gel permeation chromatograph (GPC))

(C) Other crystal nucleating agent (C1) Ethylene / methacrylic acid ionomer; Himiran 1707 (Mitsui DuPont Polychemical Co., Ltd.)
(C2) Talc; Microace L-1 (Nippon Talc Co., Ltd.)
(C3) Na montanate; Locomont NaV (manufactured by Clariant)
(D) Inorganic filler (D1) Glass fiber; T-187 (manufactured by Nippon Electric Glass Co., Ltd.)

[Production of resin molded products and evaluation of physical properties]
Production and evaluation of physical properties of resin molded products described in the following examples and comparative examples were performed as follows.

(1) Crystallization temperature Using a differential scanning calorimeter (DSC), the temperature is raised from 0 ° C. to 270 ° C. at 20 ° C./min, and held at 270 ° C. (molten state) for 2 minutes. After that, the crystallization peak temperature that appears when the temperature was lowered at 20 ° C./min was measured and used as the crystallization temperature (Tc).

(2) Mechanical properties <Molding conditions>
Injection molding was performed using a four-piece ISO strip (4 mm thick) mold. As a device, PS40E manufactured by Nissei Resin Co., Ltd. was used, a mold temperature was set to 95 ° C. and a cylinder temperature was set to 260 ° C., and a resin molded product was obtained under injection molding conditions of 30 seconds for injection and 20 seconds for cooling.
<Evaluation>: Tensile strength (MPa), tensile elongation (%)
It carried out according to ISO527-1.

(3) Molding cycle <Molding conditions>
Cylinder temperature 260 ° C., injection pressure; 1400 kg / cm ² , mold temperature 90 ° C.
Molding cycle: The cooling time was determined with a constant injection holding time.
<Evaluation>: High cycle formability Molded product with cylindrical bottom (outer diameter 40mmφ, height 40mm, average wall thickness 4mm) is molded under the above conditions, and the molded product has good shape and good appearance. The required time (second) of the limit of the molding cycle that can be obtained was obtained. It shows that it is excellent in high cycle moldability, so that a numerical value is low.

(4) Burr <Molding conditions>
Cylinder temperature: 260 ° C., mold temperature: 90 ° C., injection time: 20 seconds, cooling time: 20 seconds <Evaluation>: Burr forming property 100 × 100 mm When molding a flat test piece (having a film gate) (thickness 2 mm) by changing the injection pressure, the injection pressure is gradually increased from the injection pressure (SSP) immediately before the resin is fully filled, The injection pressure (BP) at which burrs are observed is measured. The injection pressure range is obtained from SSP to BP. When the range of the injection pressure is wider, a good molded product can be obtained under a wide range of pressure conditions, and it can be judged as easy moldability.
When the BP-SSP was 20 kgf / cm ² or more, it was evaluated as ◯, and when it was less than 20 kg / cm ² , it was marked as x.

(5) Melt retention stability <Molding conditions>
Injection molding was performed using an ISO dumbbell piece (4 mm thick) two-piece mold. As a device, PS40E manufactured by Nissei Resin Co., Ltd. was used, a mold temperature was set to 95 ° C., and a resin molded product was obtained under injection molding conditions of injection 40 seconds and cooling 20 seconds. The cylinder temperature was set to 260 ° C. from the hopper side to the nozzle side. When continuously molded under the above conditions, the residence time was set to 0 minutes, and molded products having melt residence times of 0 minutes, 5 minutes, 10 minutes, and 20 minutes were obtained. For the following evaluation, a molded product in the second shot after melt residence was used.
<Evaluation>: Tensile strength retention rate Tensile strength retention rate (%) due to retention at a high temperature by the following formula (2) was obtained using the dumbbell pieces having a retention time of 0 minutes and 20 minutes.
A sample having a tensile strength retention of 80% or more was evaluated as “◯”, and a sample having a tensile strength retention of less than 80% was evaluated as “×”.

[Examples 1-9, Comparative Examples 1-5]
A1 to A3, B1 to B3, and C1 to C3 were dry blended at the compounding ratio shown in Table 1 below, and melt kneaded using a twin screw extruder (manufactured by Toshiba Machine Co., Ltd .: TEM58). Extrusion was performed at a screw speed of 200 rpm, a cylinder temperature of 250 ° C. (the polymer temperature near the tip nozzle was 270 ° C.), an extrusion rate of 150 kg / Hr (residence time of 1 minute), and a reduced pressure of 0.05 MPa. The polymer was discharged in a strand form from the tip nozzle, and water-cooled and cut into pellets. After the pellets were dried at 120 ° C. for 5 hours with a dehumidifying dryer, test pieces were prepared by the injection molding method described above, and the test pieces were analyzed and measured for various properties according to the measurement methods described above. The results are shown in Table 1.

[Example 10, Comparative Example 6]
A2 and B1 were dry blended at the blending ratio shown in Table 1 below. The blend was melt-kneaded using a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd .: TEX-54), and D1 was added from the side feeder at a compounding ratio shown in Table 1. Extrusion was performed at a screw speed of 200 rpm, a cylinder temperature of 250 ° C. (the polymer temperature near the tip nozzle was 285 ° C.), an extrusion rate of 150 kg / Hr (residence time of 1 minute), and a reduced pressure of 0.05 MPa. The polymer was discharged in a strand form from the tip nozzle, and water-cooled and cut into pellets. After the pellets were dried at 120 ° C. for 5 hours with a dehumidifying dryer, test pieces were prepared by the injection molding method described above, and the test pieces were analyzed and measured for various properties according to the measurement methods described above. The results are shown in Table 1.

  The resin composition of the present invention has a short molding cycle, greatly improves burrs during molding, and is excellent in melt residence stability. Therefore, it is widely used for various moldings from small high cycle molding to large molding with a long residence time. be able to. In addition, the resin composition of the present invention can be suitably used as an electric / electronic part or an automobile part as an application in which the above features can be utilized.

Claims (7)

  (A) Polytrimethylene containing 0.01 to 10 parts by weight of a styrene copolymer containing an epoxy group having an epoxy value of 0.1 to 10 meq / g with respect to 100 parts by weight of polytrimethylene terephthalate A terephthalate resin composition.   The polytrimethylene terephthalate resin composition according to claim 1, wherein the component (B) has a weight average molecular weight of 500 to 50,000.   The polycrystal according to claim 1 or 2, wherein a crystallization temperature (Tc) when the temperature is lowered from a molten state at 270 ° C using a differential scanning calorimeter (DSC) is 175 ° C or higher. Trimethylene terephthalate resin composition.   (B) The polytrimethylene terephthalate resin composition in any one of Claims 1-3 whose compounding quantity of a component is 0.3-3 weight part with respect to 100 weight part of (A) component.   The molded object which consists of a polytrimethylene terephthalate resin composition in any one of Claims 1-4.   An automobile part comprising the polytrimethylene terephthalate resin composition according to any one of claims 1 to 4.   An electrical / electronic component comprising the polytrimethylene terephthalate resin composition according to claim 1.