JP2018021129A - Polyethylene terephthalate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyethylene terephthalate resin composition excellent in crystallization in a low-temperature region, and a molded article containing the resin composition.SOLUTION: The polyethylene terephthalate resin composition contains (A) a polyethylene terephthalate resin, (B) a compound represented by a general formula (1), and (C) a crystal nucleating agent. The content of the compound (B) represented by a general formula (1) is 1 pt.mass or more and 40 pts.mass or less based on 100 pts.mass of the polyethylene terephthalate resin (A). The content of the crystal nucleating agent (C) is 0.05 pt.mass or more and 20 pts.mass or less based on 100 pts.mass of the polyethylene terephthalate resin (A). (In the formula, Aand Aeach independently represent a 4-18C alkyl group or a 7-18C aralkyl group.)SELECTED DRAWING: None

Description

  The present invention relates to a polyethylene terephthalate resin composition. More specifically, the present invention relates to a polyethylene terephthalate resin composition that can be suitably used for household goods, household electrical appliance parts, automobile parts, and the like, and a molded body of the composition.

  Polyethylene terephthalate (PET) usually has insufficient crystallization speed in the mold temperature range (about 80 ° C) used for injection molding of other plastic resins, so mechanical properties, dimensional stability, and shape stability Therefore, it is difficult to obtain a molded product that can withstand practical use.

  In order to solve this problem, a method for promoting crystallization of PET by using a high-temperature mold of 120 to 150 ° C. has been studied, but there is a problem in terms of economy and versatility.

  Therefore, in order to realize the crystallization of PET in a low temperature mold, a method of adding a crystal nucleating agent has been studied conventionally. For example, in Patent Document 1, a crystal nucleating agent composed of inorganic particles typified by talc is blended in an amount of 0.1 to 3% by weight, or in Patent Document 2, an alkali metal salt of an organic carboxylic acid is blended. It has improved.

  Moreover, in patent document 3, the crystallization rate of PET is improved by combining a crystal nucleating agent and a specific ether compound, and the thermal contraction rate when held in a high-temperature atmosphere in an injection-molded product with an 80 ° C. mold. Suppressed.

  On the other hand, in Patent Document 4, a specific bisphenyl ketone compound is used as a melt viscosity reducing agent (thickening agent) that reduces the melt viscosity without reducing the degree of polymerization of the resin.

Japanese Patent Publication No. 44-7542 Japanese Patent Publication No. 48-4097 JP 58-93752 A Japanese Patent Laid-Open No. 5-25372

  However, according to the techniques of Patent Documents 1 to 3, the crystallization of the injection molded body in the 80 ° C. mold is still insufficient, and a further crystallization promotion technique in the low temperature mold is desired. In addition, the bisphenyl ketone compound disclosed in Patent Document 4 has not been known to improve the crystallization rate at low temperatures.

  In view of the above, the present invention relates to a polyethylene terephthalate resin composition excellent in crystallization in a low-temperature region, and a molded body containing the resin composition.

  Therefore, as a result of diligent studies to solve the above problems, the present inventors have added a crystal nucleating agent and a specific plasticizer in combination to PET, so that PET can be crystallized particularly in a low temperature region. The inventors have found that an injection molded product that has been sufficiently crystallized in a short molding cycle using an 80 ° C. mold can be provided by increasing the speed, and the present invention has been completed.

That is, the present invention relates to the following [1] to [2].
[1] A polyethylene terephthalate resin composition comprising (A) a polyethylene terephthalate resin, (B) a compound represented by the general formula (1), and (C) a crystal nucleating agent,
The content of the compound represented by (B) the general formula (1) is 1 part by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the (A) polyethylene terephthalate resin, and the content of the (C) crystal nucleating agent is (A) The polyethylene terephthalate resin composition which is 0.05 mass part or more and 20 mass parts or less with respect to 100 mass parts of polyethylene terephthalate resin.

(Wherein, A ₁ and A ₂ each independently represents an alkyl group having 4 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms)
[2] A molded article comprising the polyethylene terephthalate resin composition according to [1].

  The polyethylene terephthalate resin composition of the present invention has excellent crystallization speed in a low temperature region, good bleed resistance, and excellent moldability.

FIG. 1 shows a calibration curve used in determining the proportion of crystal parts in a sheet in the examples.

[Polyethylene terephthalate resin composition]
The polyethylene terephthalate resin composition of the present invention contains (B) a compound represented by the following general formula (1) and (C) a crystal nucleating agent with respect to (A) polyethylene terephthalate resin, respectively. It is characterized by.

  In general, polymer crystallization proceeds in two stages, ie, formation of crystal nuclei and growth of crystals. Crystal growth is rate-determined at low temperatures, and nucleation is rate-determined at high temperatures. It is known. Conventionally, when a crystal nucleating agent is added, the formation of crystal nuclei is improved, but the effect of addition cannot be sufficiently obtained because of insufficient crystal growth in a low temperature region. On the other hand, in the present invention, it has been found that by using a compound having a specific structure in combination with the formation of crystal nuclei, the growth of crystals is promoted and the crystallization speed is dramatically improved. This is because the polymer and the specific compound interact with each other with a good affinity based on the structure, so that the interaction between the polymer chains is relaxed, the distance between the molecular chains is increased, and the molecular mobility is increased. In order to improve, it is thought that the crystal growth is also improved. And since the above-mentioned compound is excellent in heat resistance at high temperature, even if melt-kneading of polyethylene terephthalate having a melting point of about 260 ° C. is performed at high temperature, the effect of the compound is sufficiently exerted, and bleed resistance is improved. Will also be excellent. In addition, since polyethylene terephthalate is an ester-based resin, a reaction due to hydrolysis or transesterification is likely to occur. However, since the compound has a functional group that hardly promotes ester bond or hydrolysis, the degree of polymerization of polyethylene terephthalate is reduced. Is suppressed, and the resulting resin composition is considered to be stable. However, these assumptions do not limit the present invention. In the present invention, the low temperature region means a temperature range of about 60 to 100 ° C.

[(A) Polyethylene terephthalate resin]
The polyethylene terephthalate resin (PET) used in the present invention is not particularly limited as long as it contains a polymer compound composed of terephthalic acid and ethylene glycol. It may be synthesized according to a known method or may be a commercially available product.

  The weight average molecular weight of the polyethylene terephthalate resin used in the present invention is preferably 10,000 or more, more preferably 15,000 or more, from the viewpoint of improving the mechanical properties of a molded article comprising the polyethylene terephthalate resin composition. From the viewpoint of improving the fluidity during molding, it is preferably 40000 or less, more preferably 30000 or less, still more preferably 25000 or less, and still more preferably 20000 or less. The weight average molecular weight of the polyethylene terephthalate resin here may be the molecular weight of the polyethylene terephthalate resin used as a raw material, or the molecular weight of the polyethylene terephthalate resin in the resin composition. In this specification, it can measure as a molecular weight in a resin composition according to the method as described in the below-mentioned Example, for example.

  (A) The content of the polyethylene terephthalate resin is preferably 50% by mass or more, more preferably 60% by mass or more, and more preferably 70% by mass or more in the polyethylene terephthalate resin composition from the viewpoints of improving resin physical properties and economical efficiency. Is more preferable, 80% by mass or more is more preferable, and 90% by mass or more is more preferable. Further, from the viewpoint of crystallization speed, 98.5% by mass or less is preferable, 95% by mass or less is more preferable, and 90% by mass or less is more preferable.

[(B) Plasticizer]
In the present invention, a compound represented by the following general formula (1) is used as a plasticizer.

(Wherein, A ₁ and A ₂ each independently represents an alkyl group having 4 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms)

A ₁ and A ₂ in the general formula (1) each independently represent an alkyl group having 4 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms.

  The alkyl group having 4 to 18 carbon atoms may be linear or branched. The alkyl group has 4 to 18 carbon atoms, preferably 6 or more from the viewpoint of improving the crystallization speed, and preferably 16 or less, more preferably 12 or less from the viewpoint of bleed resistance. Specific examples include butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, hexadecyl, octadecyl and the like.

  The aralkyl group having 7 to 18 carbon atoms has preferably 8 or more carbon atoms from the viewpoint of improving the crystallization speed, and preferably 16 or less, more preferably 12 or less, further from the viewpoint of bleed resistance. Preferably it is 10 or less. Specific examples include a benzyl group, a phenethyl group, a phenylpropyl group, a phenylpentyl group, a phenylhexyl group, a phenylheptyl group, and a phenyloctyl group.

  In addition, the said alkyl group and aralkyl group may have a substituent, for example, the total carbon number of the whole functional group including a substituent is in the said range. Examples of the substituent include halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom; acyl groups having 1 to 6 carbon atoms such as acetyl group and propionyl group; aralkyl groups; aralkyloxy groups; An alkylamino group having 6 carbon atoms; a dialkylamino group having 1 to 6 carbon atoms in the alkyl group.

  Specific examples of the compound represented by the general formula (1) include the following compounds.

  The compound represented by the general formula (1) is not particularly limited as long as it has the above structure, and can be prepared according to a known method. For example, diphenyl ether may be reacted with an alkyl carboxylic acid halide having 4 to 18 carbon atoms or an aryl carboxylic acid halide having 7 to 18 carbon atoms in a Lewis acid catalyst. Moreover, you may use a commercial item.

  From the viewpoint of heat resistance, the molecular weight of the compound represented by the general formula (1) is preferably 300 or more, more preferably 350 or more, still more preferably 400 or more, still more preferably 450 or more. Polyethylene terephthalate resin glass From the viewpoint of the transition point lowering effect, it is preferably 1000 or less, more preferably 800 or less, still more preferably 600 or less, and still more preferably 550 or less. In the present specification, the molecular weight of the compound represented by the general formula (1) can be calculated based on the atomic weight of the constituent atoms.

  In the present invention, a plasticizer other than the compound represented by the general formula (1) can be used in combination as long as the effects of the present invention are not impaired.

  The content of the compound represented by the general formula (1) is 1 part by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the polyethylene terephthalate resin, but preferably 2 parts by mass from the viewpoint of crystallization speed. Or more, more preferably 3 parts by mass or more, further preferably 4 parts by mass or more, more preferably 7 parts by mass or more, further preferably 10 parts by mass or more, and from the viewpoint of bleed resistance, preferably 30 parts by mass or less, More preferably, it is 25 parts by mass or less, and from the viewpoint of economy, it is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, still more preferably 12 parts by mass or less, still more preferably less than 11 parts by mass, and even more. Preferably it is 8 mass parts or less.

  Further, the content of the compound represented by the general formula (1) in the polyethylene terephthalate resin composition of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, from the viewpoint of crystallization speed. Preferably it is 3% by mass or more, more preferably 4% by mass or more, more preferably 7% by mass or more, and further preferably 10% by mass or more. From the viewpoint of bleed resistance, it is preferably 29% by mass or less, more preferably 23 mass% or less, More preferably, it is 20 mass% or less, From a viewpoint of economical efficiency, Preferably it is 17 mass% or less, More preferably, it is 13 mass% or less, More preferably, it is 11 mass% or less, More preferably, it is 10 mass% Hereinafter, it is more preferably 7% by mass or less.

[(C) Crystal nucleating agent]
The polyethylene terephthalate resin composition of the present invention uses a crystal nucleating agent in addition to the above components from the viewpoint of improving the crystallization rate.

  Examples of the crystal nucleating agent include inorganic crystal nucleating agents and organic crystal nucleating agents.

  As the inorganic crystal nucleating agent, inorganic powders such as talc, mica, aluminum silicate, aluminum calcium silicate, and metal oxide can be used.

  As the organic crystal nucleating agent, organic carboxylic acid alkali metal salts, organic nitrogen-containing compounds, phenylphosphonic acid zinc salts and the like can be used. Organic carboxylic acid alkali metal salts include sodium benzoate, potassium benzoate, lithium benzoate, lithium terephthalate, sodium terephthalate, potassium terephthalate, sodium laurate, potassium laurate, sodium myristate, potassium myristate, octacosanoic acid Examples include sodium, sodium stearate, potassium stearate, lithium stearate, sodium montanate, sodium toluate, sodium salicylate, potassium salicylate, potassium dibenzoate, lithium dibenzoate, sodium β-naphthalate, sodium cyclohexanecarboxylate. Organic nitrogen-containing compounds include lauric acid amide, stearic acid amide, ethylene bis lauric acid amide, ethylene bis stearic acid amide, ethylene bis oleic acid amide, ethylene bis 12-hydroxy stearic acid amide, palmitic acid amide, hydroxy stearic acid amide In addition to carboxylic acid amides such as Adeka Corporation, Adeka Stub NA-05 (trade name) may be mentioned.

  These can be used alone or in combination of two or more. Among them, from the viewpoint of crystallization speed, an organic crystal nucleating agent is preferable, sodium benzoate, monomethyl sodium terephthalate, sodium stearate, organic nitrogen-containing compound, and phenylphosphonic acid zinc salt are more preferable, sodium benzoate, Organic nitrogen-containing compounds are more preferable.

  The content of the crystal nucleating agent is 0.05 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polyethylene terephthalate resin. From the viewpoint of crystallization speed, it is preferably 0.1 parts by mass or more, more preferably. Is 0.3 parts by mass or more, more preferably 0.5 parts by mass or more, and from the viewpoint of resin physical properties, preferably 12 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 5 parts by mass or less, Preferably it is 3 mass parts or less, More preferably, it is 1.5 mass parts or less.

  The content of the crystal nucleating agent in the polyethylene terephthalate resin composition of the present invention is preferably 0.04% by mass or more, more preferably 0.25% by mass or more, and still more preferably 0, from the viewpoint of crystallization speed. From the viewpoint of resin properties, it is preferably 17% by mass or less, more preferably 11% by mass or less, preferably 9% by mass or less, more preferably 5% by mass or less, and further preferably 3% by mass. Hereinafter, it is more preferably 1.5% by mass or less.

  Further, the content mass ratio of the compound represented by the general formula (1) and the crystal nucleating agent (compound represented by the general formula (1) / crystal nucleating agent) is preferably 3 or more from the viewpoint of the crystallization speed, 10 or more are more preferable, and from the same viewpoint, 60 or less is preferable, 50 or less is more preferable, and 40 or less is still more preferable.

  The polyethylene terephthalate resin composition of the present invention includes hydrolysis inhibitors, fillers (inorganic fillers, organic fillers), flame retardants, antioxidants, lubricants, ultraviolet absorbers, antistatics as components other than those described above. An agent, an antifogging agent, a light stabilizer, a pigment, an antifungal agent, an antibacterial agent, a foaming agent, and the like can be contained as long as the effects of the present invention are not impaired. Similarly, other polymer materials and other resin compositions can be contained within a range that does not impair the effects of the present invention.

In addition, in this invention, it does not prevent using the component described as a compound represented by above-mentioned General formula (1) and a crystal nucleating agent as another component. That is, if the compound represented by the general formula (1) and the crystal nucleating agent are each contained in a specific amount, talc or mica that can be used as the crystal nucleating agent is further included as an inorganic filler, for example. Are included in the present invention. Therefore, as one aspect of the polyethylene terephthalate resin composition of the present invention,
A polyethylene terephthalate resin composition comprising (A) a polyethylene terephthalate resin, (B) a compound represented by the general formula (1), and (C) one or two selected from talc and mica. The content of the compound represented by (B) the general formula (1) is selected from 1 part by mass to 40 parts by mass with respect to 100 parts by mass of the (A) polyethylene terephthalate resin, (C) talc and mica. The polyethylene terephthalate resin composition whose content of 1 type or 2 types is 1 to 50 mass parts with respect to 100 mass parts of (A) polyethylene terephthalate resin can be mentioned. In this case, (C) component shall contain 0.05 mass part or more and 20 mass parts or less of crystal nucleating agent with respect to 100 mass parts of polyethylene terephthalate resin.

  The polyethylene terephthalate resin composition of the present invention can be prepared without particular limitation as long as it contains the components (A), (B), and (C). For example, a polyethylene terephthalate resin, a general formula (1) ), A crystal nucleating agent, and, if necessary, a raw material containing other additives, a known kneader such as a closed kneader, a single or twin screw extruder, an open roll kneader, etc. And can be prepared by melt kneading. The raw materials can be subjected to melt kneading after being uniformly mixed in advance using a Henschel mixer, a super mixer, or the like. In preparing the polyethylene terephthalate resin composition, in order to promote the plasticity of the polyethylene terephthalate resin, it may be melt-mixed in the presence of a supercritical gas. After the melt-kneading, the melt-kneaded product may be dried according to a known method.

  From the viewpoint of improving the moldability and prevention of deterioration of the polyethylene terephthalate resin composition, the melt kneading temperature is preferably 220 ° C or higher, more preferably 225 ° C or higher, further preferably 230 ° C or higher, preferably 300 ° C or lower, More preferably, it is 290 degrees C or less, More preferably, it is 280 degrees C or less. The melt-kneading time cannot be generally determined depending on the melt-kneading temperature and the type of the kneader, but is preferably 15 seconds or more and 900 seconds or less.

  The polyethylene terephthalate resin composition of the present invention thus obtained has a glass transition temperature (Tg) of preferably 20 ° C. or higher, more preferably 30 ° C. or higher, further preferably 40 ° C. from the viewpoint of crystallization speed and moldability. It is above, Preferably it is 70 degrees C or less, More preferably, it is 60 degrees C or less, More preferably, it is 50 degrees C or less. In addition, in this specification, a glass transition temperature (Tg) can be calculated | required according to the method as described in the below-mentioned Example.

  The polyethylene terephthalate resin composition of the present invention has a relative crystallinity with respect to the crystal-saturated polyethylene terephthalate resin, preferably from 80% or more, more preferably from 90% or more, from the viewpoint of moldability. In the present specification, if the relative crystallinity is 80% or more, it means that the crystallinity is high. The relative crystallinity can be measured by the method described in Examples described later.

  Since the polyethylene terephthalate resin composition of the present invention has high heat resistance and an excellent crystallization rate even in a low temperature region of about 80 ° C. or less, various molding processes such as injection molding, extrusion molding, thermoforming, etc. By using the method, it can be suitably used for daily goods, household appliance parts, automobile parts, and the like.

[Molded body]
The present invention also provides a molded article containing the polyethylene terephthalate resin composition of the present invention by using the above-described molding method and the like.

  For example, when producing a molded body containing the polyethylene terephthalate resin composition of the present invention by injection molding, the polyethylene terephthalate resin composition pellets are filled into an injection molding machine and injected into a mold for molding. Is obtained.

  As the injection molding, a known injection molding machine can be used. For example, those having a cylinder and a screw inserted through the cylinder as main components [J75E-D, J110AD-180H (manufactured by Nippon Steel Works), etc.] can be mentioned. In addition, although the raw material of the said polyethylene terephthalate resin composition may be supplied to a cylinder and melt-kneaded as it is, it is preferable to fill into an injection molding machine what was melt-kneaded previously from a viewpoint of crystallization speed.

  The set temperature of the cylinder is preferably 220 ° C. or higher and more preferably 230 ° C. or higher from the viewpoint of workability. Moreover, 290 degrees C or less is preferable, 280 degrees C or less is more preferable, 270 degrees C or less is still more preferable, 260 degrees C or less is still more preferable. When a melt kneader is used, it means the set temperature of the cylinder of the kneader when melt kneading. The cylinder is equipped with a heater, and the temperature is adjusted accordingly. Although the number of heaters varies depending on the model and is not determined unconditionally, the heater adjusted to the set temperature is preferably at least on the melt-kneaded product discharge port side (nozzle tip side).

  The mold temperature is preferably 150 ° C. or lower, more preferably 140 ° C. or lower, still more preferably 130 ° C. or lower, and even more preferably 100 ° C. or lower, from the viewpoint of improving the crystallization speed and workability of the polyethylene terephthalate resin composition. preferable. Moreover, 20 degreeC or more is preferable, 30 degreeC or more is more preferable, 40 degreeC or more is further more preferable, and 60 degreeC or more is still more preferable. The holding time in the mold cannot be generally determined by the temperature of the mold, but is preferably 5 to 100 seconds from the viewpoint of improving the productivity of the molded body.

  In addition, when a molding method other than injection molding is used, molding may be performed according to a known method, and there is no particular limitation. The molding temperature of the present invention can also be obtained by setting the molding temperature within the aforementioned temperature range.

  The molded article of the present invention thus obtained is excellent in heat resistance and mechanical strength, so that it can be used for various applications, for example, packaging materials for daily necessities, cosmetics, household appliances, blister packs, trays, lunch box lids, etc. It can be suitably used for food containers, industrial trays used for transportation and protection of industrial parts, and the like.

  The injection-molded body of the present invention may be prepared by injection-molding the polyethylene terephthalate resin composition of the present invention, and can be prepared according to a known method. For details, the term of the polyethylene terephthalate resin composition of this invention can be referred.

  Hereinafter, the present invention will be specifically described with reference to examples. Note that this example is merely illustrative of the present invention and is not meant to be limiting. The parts in the examples are parts by mass unless otherwise specified. “Normal pressure” indicates 101.3 kPa, and “room temperature” indicates 25 ° C.

[Production Example 1 of Plasticizer] (Compound 1) BKO-C7 (4,4′-diheptyl ketone diphenyl ether compound)
Diphenyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) 5.1 g (30 mmol) in a 100 mL three-necked flask (with thermometer, dropping funnel, distillation tube, nitrogen blowing tube), aluminum chloride (anhydrous) as a catalyst (Wako Pure) 12 g (90 mmol) (manufactured by Yakuhin Kogyo Co., Ltd.) and 40 mL of dichloromethane super-dehydrate (manufactured by Wako Pure Chemical Industries, Ltd.) were added, and the mixture was cooled to 0 ° C. under normal pressure and nitrogen atmosphere and stirred for 15 minutes. 10 mL of a dichloromethane solution of 10.7 g (66 mmol) of octanoyl chloride (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise at 0 ° C., stirred for 20 minutes, then warmed to room temperature and stirred for 16 hours. After completion of the reaction, the mixture was poured into 120 mL of ice water, 120 mL of dichloromethane was added and stirred, and then extracted twice with 100 mL of dichloromethane. The organic phases were combined, washed with water and saturated brine, dried over anhydrous magnesium sulfate, the desiccant was filtered off, and the solvent was distilled off under reduced pressure. The obtained crude product was dissolved in chloroform and recrystallized by adding hexane to obtain white crystals (Compound 1).

[Plasticizer Production Example 2] (Compound 2) BKO-C9 (4,4′-dinonyl ketone diphenyl ether compound)
A 1 L 4-necked flask (with thermometer, dropping funnel and nitrogen blowing tube) 57.2 g (0.34 mol) of diphenyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) and aluminum chloride (anhydrous) (Wako Pure Chemical) as a catalyst 112 g (0.84 mol) manufactured by Kogyo Co., Ltd. and 560 mL of dichloromethane super-dehydrated (manufactured by Wako Pure Chemical Industries, Ltd.) were added, cooled to 0 ° C. under normal pressure and nitrogen atmosphere, and stirred for 15 minutes. A mixed solution of 141 g (0.74 mol) of decanoyl chloride (manufactured by Wako Pure Chemical Industries, Ltd.) and 100 mL of dichloromethane was added dropwise at 0 ° C., stirred for 20 minutes, then warmed to room temperature and stirred for 12 hours. After completion of the reaction, the mixture was poured into 1 L of 2N hydrochloric acid at 0 ° C., and extracted with 1 L of dichloromethane. The organic phases were combined, washed with water and saturated brine, dried over anhydrous magnesium sulfate, the desiccant was filtered off, and the solvent was distilled off under reduced pressure. The obtained crude product was dissolved in chloroform and reprecipitated by adding hexane to obtain white crystals (compound 2).

[Production Example 3 of Plasticizer] (Compound 3) BKO-C11 (4,4′-diundecyl ketone diphenyl ether compound)
9.4 g (0.055 mol) of diphenyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) in a 500 mL four-necked flask (with a thermometer, a dropping funnel, and a nitrogen blowing tube), and aluminum chloride (anhydrous) (Wako Pure Chemical Industries) as a catalyst 18.3 g (manufactured by Kogyo Co., Ltd.) and 80 mL of dichloromethane ultra-dehydrated (manufactured by Wako Pure Chemical Industries, Ltd.) were added, and the mixture was cooled to 0 ° C. and stirred for 15 minutes under normal pressure and nitrogen atmosphere. A mixed solution of 26.6 g (0.12 mol) of dodecanoyl chloride (manufactured by Wako Pure Chemical Industries, Ltd.) and 30 mL of dichloromethane was added dropwise at 0 ° C., stirred for 20 minutes, then warmed to room temperature and stirred for 16 hours. After completion of the reaction, the mixture was poured into 200 mL of ice water, and extracted with 100 mL of dichloromethane. The organic phases were combined, washed with water and saturated brine, dried over anhydrous magnesium sulfate, the desiccant was filtered off, and the solvent was distilled off under reduced pressure. The obtained crude product was dissolved in chloroform and recrystallized by adding hexane to obtain white crystals (compound 3).

[Production Example 4 of Plasticizer] (Compound 4) BPO-Bn (4,4′-dibenzyl ether diphenyl ether compound)
In a 500 mL four-necked flask (with a stirrer, thermometer, dropping funnel, distillation tube, nitrogen blowing tube), 50 g (0.25 mol) of 4,4′-dihydroxydiphenyl ether and tetrabutylammonium bromide as a catalyst 16. 0 g (0.50 mol) and 88.9 g (0.52 mol) of benzyl bromide (manufactured by Wako Pure Chemical Industries, Ltd.) were added, the temperature was raised to 80 ° C. under normal pressure and nitrogen atmosphere, and 48% potassium hydroxide was added. 86.6 g (0.74 mol) of an aqueous solution was slowly added dropwise. Thereafter, the temperature of the reaction solution was raised to 95 ° C., and heated and stirred for 7 hours. After cooling, the precipitated solid was dissolved in chloroform and washed with water. After confirming that the wash water had a pH of 7 to 8, 1.4 g of Kyoward (registered trademark) 600S as an adsorbent was added to the chloroform solution, followed by filtration. Hexane was added to the filtrate and recrystallization was performed to obtain white crystals (compound 4).

The raw materials used in the examples and comparative examples are as follows. The molecular weight of the plasticizer is calculated based on the atomic composition after identifying the compound by NMR.
[PET resin]
PET: Polyethylene terephthalate resin (UNIPET RT-553C, manufactured by Nihon Unipet, unreinforced)
[Plasticizer]
BKO-C7: Compound prepared in Production Example 1 of plasticizer, molecular weight 422.6
BKO-C9: compound prepared in Production Example 2 of plasticizer, molecular weight 478.7
BKO-C11: compound prepared in Production Example 3 of plasticizer, molecular weight 534.8
BPO-Bn: compound prepared in Production Example 4 of plasticizer, molecular weight 382.5
[Crystal nucleating agent]
Sodium benzoate: NA-05 (organic nitrogen-containing compound) manufactured by Wako Pure Chemical Industries, Ltd .: Talc manufactured by ADEKA: MICROACE P-6 manufactured by Nippon Talc

Examples 1-10, Comparative Examples 1-4
An aluminum cup is placed on a hot plate heated to 280 ° C., and an amount of (A) polyethylene terephthalate resin, (B) plasticizer, and (C) crystal nucleating agent having the compositions shown in Tables 1 to 3 are made of aluminum. The mixture was put into a cup and kneaded for 10 minutes using a spatula to obtain a polyethylene terephthalate resin composition (hereinafter simply referred to as a PET resin composition). About the obtained PET resin composition, relative crystallization degree, semi-crystallization time, glass transition temperature, molecular weight, and compatibility (bleed resistance) were measured / evaluated by the method described later. The results are shown in Tables 1-3.

Example 11, Comparative Example 5
The amounts of (A) polyethylene terephthalate resin, (B) plasticizer, and (C) crystal nucleating agent in the composition shown in Table 4 were respectively in the same direction meshing type twin screw extruder (TEX- manufactured by Nippon Steel Works). 28V) was melt-kneaded at 280 ° C. and strand cutting was performed to obtain PET resin composition pellets. In addition, the obtained pellet was dehumidified and dried at 110 ° C. for 7 hours, and the water content was adjusted to 50 ppm or less. With respect to the obtained PET resin composition (pellet), the relative crystallinity, semi-crystallization time, glass transition temperature, molecular weight, moldability, and compatibility (bleed resistance) were measured / evaluated by the methods described later. The results are shown in Table 4.

  In the present invention, crystallization in a low temperature region is evaluated by comprehensively evaluating the relative crystallinity, semi-crystallization time, and glass transition temperature of the obtained resin composition. More specifically, in the low-temperature region in which the crystallization effect is to be confirmed in the present invention, for example, the melt of the resin composition may be completely crystallized before reaching the low-temperature region. Measures the semi-crystallization time at 200 ° C. as one of the indices, and then evaluates the molecular mobility of the PET resin based on the glass transition temperature and the crystallinity based on the relative crystallinity for comprehensive evaluation. Make a judgment.

[Measurement of relative crystallinity]
A press sheet having a thickness of 0.4 mm was prepared from the obtained resin composition using an auto press molding machine and a hand press molding machine manufactured by Toyo Seiki Seisakusho. For production, two metal plates (ferro plates) are covered with Upilex (registered trademark) -25S (Ube Industries), and a metal spacer with a thickness of 0.4 mm and a predetermined amount (about 2 g) are sandwiched between them. Melting and compression were performed at 280 ° C. and 0.5 MPa for 1 minute, and further at 20 MPa for 1 minute. Then, using a hand press immediately, it hold | maintained at 80 degreeC and 1 Mpa for 30 second, and produced.

The obtained press sheet and the injection molded product of the PET resin composition of Example 11 and Comparative Example 5 obtained by the method described later were used for 1 minute using a mini blender (MB-2, manufactured by Osaka Chemical Co., Ltd.). Crushed. Then, it measured in the range of 5-40 degrees (Scan rate: 20 degrees / min) using wide angle X-ray apparatus MiniFlexII (made by Rigaku), and calculated the ratio of the crystal part in a sample by the following formula.
Ratio of crystal part = {(value of 22.5 °) − (value of 18.7 °)} / (value of 22.5 °) × 100
Separately, a calibration curve (FIG. 1) was drawn, and the relative crystallinity was calculated from the ratio of the crystal parts obtained earlier (100% is equivalent to the crystal sheet, and 0% is the amorphous sheet).

[Semi-crystallization time measurement]
Using a differential scanning calorimeter analyzer DSC8500 (manufactured by PerkinElmer), the semi-crystallization time of the PET resin composition defined under the following measurement conditions was determined.
Measurement conditions: Weigh about 8 mg of sample in a standard aluminum pan manufactured by PerkinElmer, set the prepared aluminum pan on DSC8500, raise the temperature from 25 ° C. to 280 ° C. at 15 ° C./min, and hold at 280 ° C. for 2 minutes. . Thereafter, the temperature was cooled from 280 ° C. to 200 ° C. at 750 ° C./min, and the area where 50% crystallization progressed was calculated from the exothermic peak resulting from crystallization, and the time was defined as the half crystallization time. .
In the present invention, for the convenience of measurement, crystallization was completed before reaching the low temperature region and evaluation could not be performed. Therefore, a semi-crystallization time at 200 ° C. was obtained as a reference value, and an index for crystallization evaluation. Measured as one of

[Glass transition temperature measurement]
Using a differential scanning calorimeter “DSC8500” (manufactured by PerkinElmer), the inflection point of 2ndRUN measured under the following measurement conditions was defined as the glass transition temperature (Tg).
Measurement conditions: Weigh about 8 mg of sample in a standard aluminum pan manufactured by PerkinElmer, set the prepared aluminum pan on DSC8500, raise the temperature from 25 ° C. to 280 ° C. at 15 ° C./min, and hold at 280 ° C. for 2 minutes. (1stRUN). After cooling from 280 ° C. to 25 ° C. at 750 ° C./min, the temperature is raised from 25 ° C. to 280 ° C. at a rate of 15 ° C./min (2ndRUN).
In the present invention, the decrease in Tg was measured as one index for evaluating crystallization (improving the crystal growth rate) by improving the molecular mobility of PET.

[Compatibility evaluation of plasticizer (bleed resistance)]
When the glass transition temperature of the resin composition measured under the above conditions is lower than before the addition of the plasticizer, it is judged that the plasticizer is compatible with the PET resin, and the glass transition temperature is lowered. The mass part of the missing plasticizer was defined as the compatibility limit of the plasticizer with respect to the PET resin. The compatibility of the plasticizer with respect to PET resin was evaluated according to the following criteria. In the order of ABC, the compatibility is good and the bleed resistance is excellent. When the compatibility is deteriorated, the physical properties of the resin composition may be lowered.
A: The glass transition temperature is lowered, and the plasticizer is completely compatible with each other and does not bleed out.
B: After the glass transition temperature does not decrease, a plasticizer within 10 parts by mass is added. Some incompatible bleed-out plasticizers.
C: More plasticizer than 10 parts by mass is added after the glass transition temperature is not lowered. There are many incompatible bleed-out plasticizers.

[Molecular weight measurement]
0.6 mg of PET resin composition is dissolved in 2 g of HFIP (1,1,1,3,3,3-Hexafluoro-2-propanol Wako Pure Chemical Industries) overnight, and gel permeation chromatography (GPC) is performed according to the following conditions. It was measured by.
Measuring device: HLC-8320GPC (manufactured by TOSOH)
Eluent: HFIP / 0.5 mM sodium trifluoroacetate Flow rate: 0.2 mL / min
Measurement temperature: 40 ° C
Analytical column: TSK-Gel Super AWM-H (manufactured by TOSOH)
Calibration curve: ShodexSTANDARD M-75
Polymethyl methacrylate (PMMA)

[Formability evaluation of injection molding]
The PET resin composition (pellet) was injection molded using an injection molding machine (J110AD-180H manufactured by Nippon Steel Works, 6 cylinder temperature settings). The cylinder temperature was set to 245 to 270 ° C. at the nozzle tip, 260 to 275 ° C. from the second unit to the fifth unit from the tip side, 220 to 230 ° C. for the remaining unit, and 45 ° C. below the hopper. The mold temperature was set to 80 ° C., the holding time in the mold was 30 seconds, and a flat plate test piece (127 mm × 12.7 mm × 1.6 mm) was molded to obtain a molded body of the PET resin composition. The state of the injection molded body at that time was observed, and the moldability was evaluated according to the following criteria. It shows that the moldability is excellent in the order of ABC.
A: The molded body can be taken out from the movable side of the mold without being deformed when released from the mold.
B: The molded body is slightly deformed when released from the mold, or the molded body remains on the fixed side of the mold.
C: When the mold is released from the mold, the molded body is greatly deformed, and the molded body remains on the fixed side of the mold.

  From the evaluation of relative crystallinity measurements in Tables 1 to 4, crystal nucleating agents (Na benzoate, NA-05, talc) and specific plasticizers (BKO-C7, BKO-C9, BKO-C11) with respect to PET In combination, the melt crystallization speed of PET in the low temperature region (80 ° C.) was improved. Further, the effect of improving the crystallization speed by the combination of the crystal nucleating agent and the plasticizer appears well even when the content of the plasticizer is 10 parts by mass or less. For example, as apparent from Table 4, 5 parts by mass When added, PET having a relative crystallinity of 100% could be injection-molded with a low-temperature mold at 80 ° C.

  As described above, the plasticizer having a specific structure has good compatibility with the PET resin, and is excellent in high heat resistance that does not volatilize at the kneading temperature of PET (280 ° C.). It can be seen that there is a good crystallization improvement effect also in crystallization.

  Since the polyethylene terephthalate resin composition of the present invention can provide a good molded article even in injection molding using a low temperature mold, it is possible to provide daily miscellaneous goods, household appliance parts, packaging materials for household appliance parts, automobiles, etc. It can be suitably used for various industrial uses such as parts.

Claims (7)

A polyethylene terephthalate resin composition comprising (A) a polyethylene terephthalate resin, (B) a compound represented by the general formula (1), and (C) a crystal nucleating agent,
The content of the compound represented by (B) the general formula (1) is 1 part by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the (A) polyethylene terephthalate resin, and the content of the (C) crystal nucleating agent is (A) The polyethylene terephthalate resin composition which is 0.05 mass part or more and 20 mass parts or less with respect to 100 mass parts of polyethylene terephthalate resin.

(Wherein, A ₁ and A ₂ each independently represents an alkyl group having 4 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms)   (B) Polyethylene terephthalate resin of Claim 1 whose content of the compound represented by General formula (1) is 3 to 20 mass parts with respect to 100 mass parts of (A) polyethylene terephthalate resin. Composition.   The polyethylene terephthalate resin composition of Claim 1 or 2 whose glass transition temperature (Tg) of a polyethylene terephthalate resin composition is 20 degreeC or more and 70 degrees C or less.   The polyethylene terephthalate resin composition according to any one of claims 1 to 3, wherein a relative crystallinity with respect to the crystal-saturated polyethylene terephthalate resin is 80% or more.   (B) The polyethylene terephthalate resin composition in any one of Claims 1-4 whose molecular weight of the compound represented by General formula (1) is 300-1000.   The polyethylene terephthalate resin composition according to claim 1, which is for injection molding.   The molded object containing the polyethylene terephthalate resin composition in any one of Claims 1-6.

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