JP4422313B2 - Method for producing resin composition - Google Patents

Description

【００８５】
【表２】

【００８６】
［実施例２〜５］
ポリテトラメチレンテレフタレート（Ｂ）の水分散体の濃度およびポリエチレンテレフタレート（Ａ）への配合量を表１に示すように変更した以外は、実施例１と同様にして、樹脂組成物のチップを得た。得られた樹脂組成物のチップをプリフォームに射出成形し、更にボトルをブロー成形した。得られたプリフォームおよびボトルについて評価した。結果を表２に示す。
【００８７】
［比較例１］
ポリテトラメチレンテレフタレート（Ｂ）を配合しないで、実施例１と同様に実施した。結果を表１および表２に示す。
【００８８】
［比較例２］
ポリテトラメチレンテレフタレート（Ｂ）の配合量を変更する以外は、実施例１と同様に実施した。結果を表１および表２に示す。
【００８９】
［比較例３］
チップ状のポリテトラメチレンテレフタレート（Ｂ）を粉砕し、１００Ｍｅｓｈの篩を通過し、かつ２００Ｍｅｓｈの篩上に残る粉体とし、ポリエチレンテレフタレート（Ａ）に対して３０ｐｐｍの割合で、チップ状のポリエチレンテレフタレート（Ａ）にブレンドし、実施例１と同様に成形して評価した。結果を表１および表２に示す。
【００９０】
【発明の効果】
本発明によれば、透明性、機械的強度、耐熱性およびフレーバー性に優れるとともに、口部の十分な寸法精度を確保しながら、結晶性のばらつきが少なく生産安定性に優れ，結晶性が促進されたボトル容器用のポリエステル樹脂組成物を提供することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin composition and a method for producing the same. More specifically, the present invention relates to a polyester resin composition that can be suitably used for producing a hollow molded body and a method for producing the same.
[0002]
[Prior art]
Polyethylene terephthalate has good mechanical properties and chemical properties, and is excellent in transparency, gas barrier properties, flavor properties, and safety and hygiene properties. Therefore, it is used as a material for bottle containers such as beverages.
[0003]
A bottle container made of polyethylene terephthalate is formed by subjecting a preform previously produced by injection molding to stretch blow molding in a blow mold. For example, when used as a bottle container for a fruit juice beverage, the filling needs to be performed by heat filling, and the bottle container is required to have sufficient heat resistance particularly in the mouth portion. In order to impart this heat resistance, the mouth is heat-treated in the form of a preform or a bottle and crystallized. Since the mouth portion is a cap-sealed portion, high dimensional accuracy is required. In order to obtain sufficient dimensional accuracy, the crystallinity of the molded preform is a very important factor.
[0004]
Furthermore, from the viewpoint of obtaining good transparency and from the viewpoint of food safety, it is preferable to use polyethylene terephthalate produced by polycondensation using a germanium compound as a catalyst. However, polyethylene terephthalate produced using a germanium compound as a catalyst has a high crystallization temperature in the first place, and crystallization hardly proceeds.
[0005]
As a method for promoting crystallization, a method of adding an inorganic nucleating agent, a method of blending or copolymerizing higher aliphatic compounds and polyether compounds are known as conventional techniques. However, with these conventional technologies, there are concerns about the deterioration of transparency, thermal stability, degradation of the flavor of the contents due to the generation of decomposition components, and food safety problems. , Is insufficient.
[0006]
The above prior art includes a method of adding a trace amount of a polyolefin-based thermoplastic resin such as polypropylene or polyethylene as an additive. Specific examples thereof include JP-A-8-302168 and JP-A-9-183430. JP-A-9-71639, JP-A-9-151308, and JP-A-9-194697.
[0007]
[Problems to be solved by the invention]
These methods are excellent in that a transparent bottle container can be obtained while promoting crystallization of polyethylene terephthalate, but the compatibility between the polyolefin-based thermoplastic resin as an additive and polyethylene terephthalate is low in the first place. Therefore, it is very difficult to uniformly disperse a small amount of additive. For this reason, when the mouth part of the preform obtained by molding is crystallized, the crystallinity varies greatly and the production stability is often lowered.
[0008]
The present invention is excellent in transparency, mechanical strength, heat resistance and flavor so that it can be suitably used as a material for beverage containers, while ensuring sufficient dimensional accuracy of the mouth, It is an object of the present invention to obtain a polyester resin composition for a bottle container (hereinafter, sometimes simply referred to as a “bottle”) having little variation, excellent production stability, and enhanced crystallinity.
[0009]
[Means for Solving the Problems]
  That is, the present invention
Item 1)A method for producing a resin composition, comprising:Polytetramethylene terephthalate (B) is added to polyethylene terephthalate (A) having an intrinsic viscosity of 0.70 to 0.90 produced by polycondensation reaction using a germanium compound as a catalyst.The concentration of polytetramethylene terephthalate (B) in the resin composition isFormulated to be 5-40ppmAnd
TheResin composition in which polytetramethylene terephthalate (B) is blended by attaching an aqueous dispersion containing polytetramethylene terephthalate (B) at a concentration of 0.05 to 2 wt% to a chip of polyethylene terephthalate (A) Manufacturing method,
Item 2) The process for producing a resin composition according to claim 1, wherein an isophthalic acid component having a sulfoisophthalic acid metal base is copolymerized with polytetramethylene terephthalate (B) in an amount of 1 to 10 mol% per total dicarboxylic acid component.
Item 3) The blending of polytetramethylene terephthalate (B) to polyethylene terephthalate (A) is performed from the time of completion of melt polymerization of polyethylene terephthalate (A) to the time of molding the molded article. A method for producing the resin composition according to any one of the above,
Item 4) The method for producing a resin composition according to any one of Items 1 to 3, wherein a phosphorus compound is added when producing polyethylene terephthalate (A) by polycondensation reaction, and
Item 5) A method for producing a resin composition according to Item 4, wherein the addition amount of the phosphorus compound is 10 to 1000 ppm,
It is.
[0010]
Hereinafter, the present invention will be described in detail.
[Polyethylene terephthalate (A)]
Polyethylene terephthalate (hereinafter sometimes abbreviated as PET) used in the present invention is a polyester having terephthalic acid as a main dicarboxylic acid component and ethylene glycol as a main diol component.
[0011]
Here, the main dicarboxylic acid component refers to a component exceeding 80 mol% per total dicarboxylic acid component. Therefore, the polyethylene terephthalate (A) in the present invention may contain a dicarboxylic acid component other than terephthalic acid in a range of less than 20 mol%.
[0012]
Examples of the dicarboxylic acid component other than terephthalic acid include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenylsulfone dicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1 , 3-phenylenedioxydiacetic acid and their structural isomers, dicarboxylic acids such as malonic acid, succinic acid and adipic acid and their derivatives, oxyacids such as p-hydroxybenzoic acid and glycolic acid and their derivatives it can.
[0013]
Moreover, the main diol component means a component exceeding 90 mol% per all diol components. Accordingly, the polyethylene terephthalate (A) in the present invention may contain a diol component other than ethylene glycol in a range of less than 10 mol%, preferably at most 5 mol%, more preferably at most 3 mol%.
[0014]
Examples of diol components other than ethylene glycol include aliphatic glycols such as 1,2-propanediol, 1,3-propanediol, pentamethylene glycol and neopentyl glycol, alicyclic glycols such as cyclohexanedimethanol, bisphenol A, Aromatic dihydroxy compound derivatives such as bisphenol S can be mentioned.
[0015]
Polyethylene terephthalate (A) is produced using terephthalic acid or an ester-forming derivative thereof and ethylene glycol as main raw materials. As described above, other dicarboxylic acid components and / or other glycol components are used as raw materials. May be. A raw material containing terephthalic acid or an ester-forming derivative thereof and ethylene glycol is subjected to esterification or transesterification in the presence of an esterification catalyst or transesterification catalyst to produce bis (β-hydroxyethyl) terephthalate and / or its Oligomer. Thereafter, in the presence of a polycondensation catalyst and a stabilizer, melt polycondensation is performed under high temperature and reduced pressure to obtain a polymer.
[0016]
The esterification catalyst is not particularly required because terephthalic acid serves as an autocatalyst for the esterification reaction. As the transesterification catalyst, alkaline earth metal salts such as magnesium and calcium, and metal compounds such as titanium, zinc and manganese are preferably used, and titanium and manganese compounds are particularly preferable from the viewpoint of transparency. The use ratio of these catalysts is usually 5 to 1000 ppm, preferably 10 to 100 ppm, as the weight of the metal element of the catalyst with respect to the total polymerization raw material.
[0017]
As the polycondensation catalyst, it is necessary to use germanium dioxide from the viewpoint of satisfying color tone, transparency and food safety, and the addition amount is preferably 20 to as the weight of the germanium element with respect to the weight of the total dicarboxylic acid component. 150 ppm, more preferably 30 to 100 ppm, particularly preferably 30 to 80 ppm.
[0018]
A stabilizer may be added at the time of polymerization. As the stabilizer, phosphate esters such as trimethyl phosphate, triethyl phosphate and triphenyl phosphate, phosphite esters such as triphenyl phosphate and trisdodecyl phosphate, methyl acid phosphate Phosphorus compounds such as dibutyl phosphate, monobutyl phosphate acidic phosphoric acid ester, phosphoric acid, phosphorous acid, hypophosphorous acid and polyphosphoric acid are preferred.
[0019]
The added amount of the stabilizer is usually 10 to 1000 ppm, preferably 20 to 500 ppm, as the weight of phosphorus element in the stabilizer with respect to the total polymerization raw material.
[0020]
The catalyst and the stabilizer can be supplied at the time of preparing the raw slurry or at any time of the esterification reaction or transesterification reaction. You may supply at the initial stage of a polycondensation reaction process.
[0021]
The reaction temperature of the esterification reaction or transesterification reaction is usually 240 to 280 ° C., and the reaction pressure is normal pressure to 0.3 Mpa.
[0022]
The reaction temperature of the polycondensation reaction is usually 250 to 300 ° C., and the reaction pressure is usually 60 to 0.1 Kpa.
[0023]
The esterification reaction or transesterification reaction and polycondensation reaction may be performed in one stage or may be performed in a plurality of stages.
[0024]
In this way, a polymer having an intrinsic viscosity of usually 0.45 to 0.70 dl / g is obtained by melt polycondensation. The polymer is formed into chips by a conventional method, and is usually formed into chips having an average particle diameter of 2.0 to 5.5 mm, preferably 2.2 to 4.0 mm.
[0025]
The polymer chip obtained by the melt polymerization is subjected to solid phase polymerization. At this time, the polymer chip is preferably pre-crystallized at a temperature lower than the temperature at which solid-phase polymerization is performed.
[0026]
The pre-crystallization step is performed in a fluid state so that the amorphous polymer chip is usually melted at a temperature of 120 to 200 ° C., preferably 130 to 180 ° C., so as not to cause fusion due to crystallization heat generation of the chip. In one stage or two or more stages, it is crystallized by treating for at least 15 minutes.
[0027]
The next solid-phase polymerization step comprises at least one stage, usually at a polymerization temperature of 190 to 230 ° C., preferably 195 to 225 ° C., under a vacuum of 0.05 to 5 Kpa, or under normal pressure to 0.1 Mpa. In an inert gas flow such as nitrogen, argon or carbon dioxide.
[0028]
The solid phase polymerization time may be shorter as the temperature is higher, but is usually 1 to 50 hours, preferably 5 to 30 hours, and more preferably 10 to 25 hours.
[0029]
The intrinsic viscosity of the polymer obtained by solid phase polymerization is usually in the range of 0.70 to 0.90 dl / g.
[0030]
In the present invention, the content of diethylene glycol constituting the polyethylene terephthalate (A) is 0.7 to 2.0 wt%, preferably 1.0 to 1.5 wt%, based on all diol components constituting the polyethylene terephthalate. If it is less than 0.7 wt%, the transparency of the bottle body after molding is lowered, and if it exceeds 2.0 wt%, the heat resistance is lowered and the effect of promoting crystallization is reduced.
[0031]
In order to adjust the content of diethylene glycol within the above range, diethylene glycol may be used as a polymerization raw material, and diethylene glycol is partially produced as a by-product from ethylene glycol used as a main raw material. The amount produced may be adjusted.
[0032]
In order to reduce mold contamination during bottle molding, the oligomer content is preferably 0 to 0.5 wt%, more preferably 0 to 0.4 wt% or less, based on the total weight of the polymer.
[0033]
In order to prevent deterioration of the taste and odor of the bottle filling, the acetaldehyde content is preferably 0 to 5 ppm, more preferably 0 to 2 ppm, based on the total weight of the polymer.
[0034]
The oligomer and acetaldehyde are reduced by the above solid phase polymerization, and the above content can be satisfied by adjusting the intrinsic viscosity number, solid phase polymerization time and temperature time of the polymer after melt polymerization.
[0035]
The concentration of the terminal carboxyl group of the polyethylene terephthalate (A) is preferably 15 to 25 eq / ton. If it is this range, an oligomer can fully be reduced by solid-phase polymerization for a comparatively short time.
[0036]
[Polytetramethylene terephthalate (B)]
The polytetramethylene terephthalate (B) is a polyester having terephthalic acid as a main dicarboxylic acid component and tetramethylene glycol as a main diol component.
[0037]
The main dicarboxylic acid component means 80 mol% or more, preferably 90 mol% or more of the total dicarboxylic acid component. The main diol component means 80 mol% or more, preferably 90 mol% or more of the total diol component.
[0038]
In order to obtain solubility in a solvent, polytetramethylene terephthalate (B) contains 1 to 10 mol of an isophthalic acid component having a sulfonic acid metal base (hereinafter sometimes abbreviated as IAS) per dicarboxylic acid component. %, And further 3 to 5 mol% is preferably contained as a copolymerization component.
[0039]
Examples of IAS include 5-lithium sulfoisophthalic acid, 5-sodium sulfoisophthalic acid, and 5-potassium sulfoisophthalic acid. Among them, 5-sodium sulfoisophthalic acid is preferable.
[0040]
These may be derived from derivatives. As the derivative, for example, an ester can be used, and examples thereof include methyl ester, ethyl ester, propyl ester, and butyl ester, and methyl ester is particularly preferable.
[0041]
In the polytetramethylene terephthalate (B), the dicarboxylic acid component and / or the diol component may be substituted with a copolymer component as long as the effect of promoting crystallization is not hindered. This is preferably 20 mol% or less, more preferably 10 mol% or less of the dicarboxylic acid component, and preferably 20 mol% or less, more preferably 10 mol% or less of the diol component.
[0042]
Dicarboxylic acid components that can be used as copolymerization components include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenylsulfone dicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, Examples include 1,3-phenylenedioxydiacetic acid and structural isomers thereof, dicarboxylic acids such as malonic acid, succinic acid and adipic acid and derivatives thereof, and oxyacids such as p-hydroxybenzoic acid and glycolic acid and derivatives thereof. be able to.
[0043]
Examples of the diol component that can be used as a copolymerization component include aliphatic glycols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, pentamethylene glycol, hexamethylene glycol, and neopentyl glycol, cyclohexanedimethanol, and the like. And aromatic dihydroxy compound derivatives such as alicyclic glycol, bisphenol A, and bisphenol S.
[0044]
A raw material containing the above-mentioned terephthalic acid or its ester-forming derivative and tetramethylene glycol is subjected to an esterification reaction or an ester exchange reaction in the presence of an esterification catalyst or an ester exchange catalyst to give a tetramethylene terephthalate monomer (1 amount). ) To oligomer (polymer with low polymerization degree), and then polytetramethylene terephthalate is obtained by performing melt polycondensation under reduced pressure at high temperature in the presence of a polycondensation catalyst and, if necessary, a stabilizer. Obtainable.
[0045]
In this case, it is not necessary to use an esterification catalyst because terephthalic acid serves as an autocatalyst for the esterification reaction. As the transesterification catalyst, alkaline earth metal salts such as magnesium and calcium, and metal compounds such as titanium, zinc and manganese are preferably used, and titanium compounds are particularly preferable from the viewpoint of reactivity and transparency.
[0046]
As the polycondensation catalyst, for example, a germanium compound, an antimony compound, a titanium compound, a cobalt compound, and a tin compound can be used, and a titanium compound is preferable from the viewpoint of reactivity. The addition amount is preferably 20 to 80 ppm, more preferably 30 to 50 ppm as the weight of the titanium element with respect to the weight of the total dicarboxylic acid component.
[0047]
The catalyst and the stabilizer can be supplied at the time of preparing the raw slurry or at any time of the esterification reaction or transesterification reaction. You may supply at the initial stage of a polycondensation reaction process.
[0048]
The reaction temperature of the esterification reaction or transesterification reaction is usually 210 to 220 ° C., and the reaction pressure is normal pressure to 0.3 Mpa.
[0049]
The reaction temperature for the polycondensation reaction is usually 240 to 270 ° C., and the reaction pressure is usually 60 to 0.1 Kpa.
[0050]
The esterification reaction or the transesterification reaction and the polycondensation reaction may be performed in one stage or may be performed in two or more stages.
[0051]
Thus, a polymer having an intrinsic viscosity of usually 0.30 to 0.70 dl / g is obtained by melt polycondensation. The polymer is chipped by a conventional method.
[0052]
[Mixing method]
Polytetramethylene terephthalate (B) is blended in a proportion of 1 to 100 ppm, preferably 1 to 50 ppm, more preferably 5 to 50 ppm with respect to polyethylene terephthalate (A). If it is less than 1 ppm, there is no effect of improving crystallinity, and if it exceeds 100 ppm, fusion of the chips occurs when the chips are dried, or defective dropping of the chips occurs during molding, and the molding stability is hindered. The transparency of the resulting bottle container is reduced.
[0053]
The polytetramethylene terephthalate (B) is preferably blended by attaching an aqueous dispersion containing the polytetramethylene terephthalate (B) at a concentration of 0.05 to 2 wt% to the polyethylene terephthalate (A) chip.
[0054]
When polytetramethylene terephthalate (B) is not blended in the state of an aqueous dispersion, for example, when blended in a powder blend, it is difficult to obtain a stable crystallization promoting effect because of non-uniform blending. Absent.
[0055]
The concentration of polytetramethylene terephthalate (B) in the aqueous dispersion is usually 0.05 to 2 wt%, preferably 0.1 to 1 wt%, more preferably 0.2 to 0.5 wt%. If it is less than 0.05 wt%, it is difficult to attach an appropriate amount to the polyethylene terephthalate chip, and the intrinsic viscosity is greatly lowered by drying after treatment, which is not preferable. If it exceeds 2 wt%, it is difficult to uniformly adhere the solution to the polyethylene terephthalate chip, which is not preferable.
[0056]
As a method of using polytetramethylene terephthalate (B) as an aqueous dispersion, a method of dissolving polytetramethylene terephthalate (B) with a soluble organic solvent and replacing with water is preferable. The concentration of polytetramethylene terephthalate (B) may be adjusted by adjusting the amount of water used for substitution, or may be obtained by once obtaining a high-concentration aqueous dispersion and adding water to dilute appropriately. Good.
[0057]
As a method of attaching the aqueous dispersion of polytetramethylene terephthalate (B) to the polyethylene terephthalate (A) chip, for example, a spray method or a dip method can be applied.
[0058]
The blending of polytetramethylene terephthalate (B) is from the end of the melt polymerization of polyethylene terephthalate (A) to the time of molding the molded body, for example, when cutting into chips after melt polymerization, after solid phase polymerization It can be carried out at a point in time, before drying of the molding. From the viewpoint of suppressing deterioration of the polyethylene terephthalate (A) due to heat, the time after solid phase polymerization is preferred.
[0059]
When an aqueous dispersion is used for blending the polytetramethylene terephthalate (B), it is preferable to dry and remove moisture between the adhesion treatment of the aqueous dispersion and the molding. There is no need for drying.
[0060]
[Molding]
The molded article of the present invention is preferably a molded article having a crystallization temperature Tci of 140 to 150 ° C. at the time of temperature rise (10 ° C./min temperature rise) measured by a differential scanning calorimeter. More preferably, it is a molded product having a Tci of 5 to 15 ° C. lower than that of a molded product (for example, a molded product of polyethylene terephthalate (A)) when polytetramethylene terephthalate (B) is not blended.
[0061]
When Tci is less than 140 ° C., when the preform body is heated for blow molding, whitening due to crystallization is likely to occur, and the shoulder and body are whitened and transparent. The heat resistance may be impaired, and heat resistance is imparted, so that heating becomes difficult and heat resistance becomes insufficient. When Tci exceeds 150 ° C., the mouth portion is heated and crystallized to the desired degree of crystallinity, so that heating for a long time is required, productivity is lowered, and the mouth crystallization equipment must be enlarged. It will be. By satisfying the above Tci conditions, it is possible to simultaneously satisfy the crystallinity and transparency of the molded product and imparting heat resistance to the bottle.
[0062]
[Production method of molded products]
The resin composition of the present invention can be molded into a bottle by employing a commonly used melt molding method. Specifically, for example, a parison is formed once by injection molding or extrusion molding, and the mouth and the bottom are processed and then reheated, and a stretch blow molding method such as a hot parison method or a cold parison method is applied. .
[0063]
  In this case, the molding temperature (specifically, the temperature of each part of the cylinder of the molding machine and the nozzle) is, for example, 260 to 315 ° C, preferably 275 to 295 ° C. Stretching temperature is polyethylene terephthalate glassMetastasisAbove the temperature, it is usually 70-130 ° C. The draw ratio is usually in the range of 1 to 4 times in the longitudinal direction and 1 to 5 times in the circumferential direction.
[0064]
The obtained bottle can be used as it is, but in particular when heat filling is required, such as fruit juice drinks and oolong tea, it is generally heat-set in a heated blow mold and further given heat resistance. Is done.
[0065]
The heat setting is usually performed at a mold temperature of 100 to 200 ° C. for several seconds to several minutes under tension by compressed air or the like. Further, a method may be used in which a bottle larger than the final shape is formed, the barrel is crystallized by shrinkage by heating, and then blow-molded in a final shape mold to obtain a product bottle.
[0066]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples.
“Parts” means parts by weight.
[0067]
(1) Intrinsic viscosity number
Intrinsic viscosity number (hereinafter sometimes abbreviated as IV) is determined by weighing a certain amount of sample cut out from the top of the tip or preform bottle mouth (synonymous with the cap). , Dissolved in o-chlorophenol at a concentration of 0.012 g / ml, and measured at 25 ° C.
[0068]
(2) Crystallization temperature at elevated temperature
The crystallization temperature at the time of temperature rise (hereinafter sometimes abbreviated as Tci) is determined by using a differential scanning calorimeter (DSC MODEL2200 manufactured by DuPont) for a sample cut out from the portion corresponding to the top of the bottle mouth of the preform. The crystallization temperature Tci at the time of temperature rise measured at 10 ° C./min temperature rise condition (top temperature of the crystallization peak) was measured.
[0069]
(3) Haze
A sample (330 μm thickness) cut out to a size of 50 mm × 50 mm from the bottle body was measured with Nippon Denshoku Color and color difference meter MODEL1001DP.
[0070]
(4) Acetaldehyde content
The content of acetaldehyde (hereinafter sometimes abbreviated as AA) was measured with a headspace gas chromatography manufactured by Hitachi after freezing and pulverizing the sample, placing it in a vial, holding it at 150 ° C. for 60 minutes.
[0071]
(5) Amount of oligomer
The oligomer (hereinafter sometimes abbreviated as Cy-3) content was measured by gel-permeation chromatography using a sample obtained by weighing a certain amount of sample, dissolving it in hexafluoroisopropanol, and diluting it to a constant concentration with chloroform. Quantified with Waters 484).
[0072]
(6) Polytetramethylene terephthalate (B) concentration in the resin composition
The weight ratio of the polytetramethylene terephthalate (B) in the resin composition was calculated. Specifically, it is a value obtained by dividing the weight of the actually blended polytetramethylene terephthalate (B) by the weight of the resin composition. The weight of the polytetramethylene terephthalate (B) actually paid out was calculated by measuring the weight before blending and the weight after blending and taking the difference between the two.
[0073]
(7) Germanium element content
Quantification was performed using fluorescent X-ray (Rigaku Denki 3270E).
[0074]
(8) Diethylene glycol content
The content of diethylene glycol (hereinafter sometimes abbreviated as DEG) was measured by gas chromatography when a sample was decomposed with hydrazine.
[0075]
(9) Production of polytetramethylene terephthalate (B) and production of aqueous dispersion
Using 100 parts of dimethyl terephthalate, 6 parts of 5-sodium sulfoisophthalic acid dimethyl ester and 77 parts of 1,4-butanediol, 0.03 part of tetra-t-butoxytitanium as a catalyst, and by-produced methanol was removed from the system. And the ester exchange reaction is carried out while heating to 220 ° C., and the reaction product is polycondensed under high temperature and high vacuum to obtain polytetramethylene terephthalate (B) having an intrinsic viscosity of 0.50. , Made into chips. The obtained chip-like polytetramethylene terephthalate (B) was dissolved in tetrahydrofuran and then replaced with water to obtain an aqueous dispersion having a polytetramethylene terephthalate (B) concentration of 0.3 wt%.
[0076]
[Example 1]
A slurry composed of 40 parts of terephthalic acid and 22 parts of ethylene glycol is supplied to a polycondensation tank, and esterification is carried out under conditions of 275 ° C. and 4 hours under normal pressure, and by-product water is discharged out of the system. By reacting to an esterification reaction rate of 97%, an oligomer having a polymerization degree of 5 to 10 was obtained, and this was added to an ethylene glycol solution of trimethyl phosphoric acid (phosphorus concentration (weight ratio of phosphorus element to the solution) 5.5 wt%). 0.17 part and 0.38 part of an ethylene glycol solution of germanium dioxide (germanium dioxide concentration 1 wt%) were added, and polycondensation was carried out at 277 ° C. for 2 hours at 2000 Pa under reduced pressure for 1 hour and then at 133 Pa under reduced pressure. .
[0077]
The produced polymer was extracted in the form of a strand from an outlet provided directly connected to the cooling water tank at the bottom of the polycondensation tank, and then cooled in water, and then cut into chips to obtain polymer chips.
[0078]
After the obtained polymer chip was crystallized with a stirring fluidized crystallizer, it was dried at 140 ° C. for 3 hours under a nitrogen flow, then transferred to a packed column type solid-phase polymerization tower, and at 215 ° C. for 22 hours under a nitrogen flow. Solid-state polymerization was performed to produce chip-like polyethylene terephthalate (A).
[0079]
After spraying a certain amount of an aqueous dispersion (concentration 0.3 wt%) of polytetramethylene terephthalate (B) to the obtained chip-like polyethylene terephthalate (A), it was dried at 140 ° C. for 3 hours. A chip of a polyethylene terephthalate resin composition having a methylene terephthalate (B) concentration of 20 ppm was obtained. The results are shown in Table 1.
[0080]
The obtained resin composition chip was dried at 160 ° C. for 5 hours with a vacuum dryer, and then with an injection molding machine (M-100DM manufactured by Meiki Seisakusho Co., Ltd.) with a cylinder temperature of 275 ° C. and a screw rotation speed of 160 rpm. A cylindrical preform having an outer diameter of about 28 mm, an inner diameter of about 19 mm, a length of 136 mm, and a weight of about 56 g was injection-molded at a primary pressure time of 3.0 seconds, a mold temperature of 10 ° C., and a cycle of 30 seconds. About the obtained preform, intrinsic viscosity number, crystallization temperature (Tci), and acetaldehyde content were measured. The results are shown in Table 2.
[0081]
Further, in order to confirm the stability and uniformity of the crystallinity of the polyester, the crystallization temperature (Tci) was measured with different preforms (n = 5), and the variation was evaluated. The results are shown in Table 2.
[0082]
Subsequently, after crystallizing only the portion corresponding to the bottle mouth portion of the preform under the condition of 160 ° C. for 1 minute using a mouth plug crystallization apparatus (infrared heater), infrared rays are applied to the preform surface temperature of about 110 ° C. Preheat with heater, blow pressure 5-40kg / cm²Then, stretch blow molding was performed with a blow molding machine set at a mold temperature of 150 ° C. to form a bottle having an average body thickness of 330 μm and an internal volume of about 1.5 liters. The haze was measured about the obtained bottle. The results are shown in Table 2.
[0083]
Furthermore, in order to confirm the molding stability of a bottle, the appearance defect was confirmed with ten bottles.
[0084]
[Table 1]

[0085]
[Table 2]

[0086]
[Examples 2 to 5]
A chip of the resin composition was obtained in the same manner as in Example 1 except that the concentration of the aqueous dispersion of polytetramethylene terephthalate (B) and the blending amount in polyethylene terephthalate (A) were changed as shown in Table 1. It was. The resulting resin composition chip was injection molded into a preform, and the bottle was blow molded. The preforms and bottles obtained were evaluated. The results are shown in Table 2.
[0087]
[Comparative Example 1]
The same operation as in Example 1 was carried out without blending polytetramethylene terephthalate (B). The results are shown in Tables 1 and 2.
[0088]
[Comparative Example 2]
It implemented like Example 1 except changing the compounding quantity of a polytetramethylene terephthalate (B). The results are shown in Tables 1 and 2.
[0089]
[Comparative Example 3]
Chip-shaped polytetramethylene terephthalate (B) is pulverized, passed through a 100-Mesh sieve and remains on the 200-Mesh sieve, and in a ratio of 30 ppm to polyethylene terephthalate (A), the chip-shaped polyethylene terephthalate Blended with (A), molded and evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2.
[0090]
【The invention's effect】
According to the present invention, transparency, mechanical strength, heat resistance, and flavor are excellent, while ensuring sufficient dimensional accuracy of the mouth, there is little variation in crystallinity, excellent production stability, and crystallinity is promoted. A polyester resin composition for a bottle container can be provided.

Claims (5)

A method for producing a resin composition, wherein polytetramethylene terephthalate (B) is added to polyethylene terephthalate (A) having an intrinsic viscosity of 0.70 to 0.90 produced by polycondensation reaction using a germanium compound as a catalyst. , Blended so that the concentration of polytetramethylene terephthalate (B) in the resin composition is 5 to 40 ppm ,
The polytetramethylene terephthalate (B) is formulated by depositing aqueous dispersion containing polytetramethylene terephthalate (B) at a concentration of 0.05～2Wt% to chip polyethylene terephthalate (A), resin A method for producing the composition.   The process for producing a resin composition according to claim 1, wherein an isophthalic acid component having a sulfoisophthalic acid metal base is copolymerized with polytetramethylene terephthalate (B) in an amount of 1 to 10 mol% per total dicarboxylic acid component.   The blending of polytetramethylene terephthalate (B) to polyethylene terephthalate (A) is performed from the time of completion of melt polymerization of polyethylene terephthalate (A) to the time of molding the molded body. A method for producing a resin composition according to item 1.   The manufacturing method of the resin composition of any one of Claims 1-3 which add a phosphorus compound when manufacturing a polyethylene terephthalate (A) by carrying out a polycondensation reaction.   The method for producing a resin composition according to claim 4, wherein the addition amount of the phosphorus compound is 10 to 1000 ppm.