JP3605018B2 - Resin composition and method for producing the same - Google Patents

Description

【００８５】
【表２】

【００８６】
［実施例２〜５］
ポリヘキサ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］
ポリヘキサ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］
ポリヘキサ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］
チップ状のポリヘキサ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]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a resin composition and a method for producing the same. More specifically, it relates to a polyester resin composition and a method for producing the same, which can be suitably used for producing a hollow molded article.
[0002]
[Prior art]
Polyethylene terephthalate is used as a material for bottle containers for beverages and the like because it has good mechanical properties and chemical properties, and is excellent in transparency, gas barrier properties, flavor properties and safety and health.
[0003]
The polyethylene terephthalate bottle container is formed by stretch-blow molding a preform previously manufactured by injection molding in a blow mold. For example, when used as a bottle container for fruit juice beverages, the filling needs to be performed by hot filling, and the bottle container is required to have sufficient heat resistance, particularly at the mouth. In order to impart this heat resistance, crystallization is performed by heat-treating the mouth in a preform or bottle state. Since the mouth is a cap sealing 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]
Further, 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 a higher aliphatic compound and a polyether compound are known as conventional techniques. However, in these conventional techniques, there is a concern about a problem of a decrease in transparency, a decrease in thermal stability, a problem of a decrease in flavor of contents due to generation of decomposition components, and a problem of food safety. Is inadequate.
[0006]
The above prior art includes a method in which a small amount of a polyolefin-based thermoplastic resin such as polypropylene or polyethylene is added as an additive. Specific examples 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 and polyethylene terephthalate as additives is originally low. Therefore, it is very difficult to uniformly disperse a small amount of additives. For this reason, when crystallizing the mouth part of the preform obtained by molding, the crystallinity greatly varies and the production stability often decreases.
[0008]
The present invention has excellent transparency, mechanical strength, heat resistance and flavor as well as crystallinity while ensuring sufficient dimensional accuracy of the mouth so that it can be suitably used as a material for beverage containers. An object of the present invention is to obtain a polyester resin composition for a bottle container (hereinafter, sometimes simply referred to as a bottle) with little variation, excellent production stability, and enhanced crystallinity.
[0009]
[Means for Solving the Problems]
That is, the present invention
Item 1) Polyethylene methylene terephthalate (B) is converted into polyethylene terephthalate (A), polyethylene terephthalate (B) is converted into polyethylene terephthalate (A) having an intrinsic viscosity of 0.70 to 0.90, which is produced by performing a polycondensation reaction using a germanium compound as a catalyst. A resin composition blended with 1 to 100 ppm,
Item 2) Polyethylene methylene terephthalate (B) is converted into polyethylene terephthalate (A), polyhexamethylene terephthalate (B) is converted into polyethylene terephthalate (A), and polyethylene terephthalate (B) having an intrinsic viscosity of 0.70 to 0.90 produced by a polycondensation reaction using a germanium compound as a catalyst A method for producing a resin composition, which is blended so as to be 1 to 100 ppm with respect to the resin composition.
Item 3) Polyhexamethylene terephthalate (B) is compounded by attaching an aqueous dispersion containing polyhexamethylene terephthalate (B) at a concentration of 0.05 to 2 wt% to a polyethylene terephthalate (A) chip. , A method for producing a resin composition according to item 2,
Item 4) A resin composition produced by the production method according to Item 3,
Item 5) Polyethylene terephthalate (A) is produced by solid phase polymerization, contains 0.7 to 2.0% by weight of a diethylene glycol component as a component of the polymer, 0 to 0.5% by weight of an oligomer, and 0 to 5 ppm of acetaldehyde. The resin composition according to item 1, characterized by containing
Item 6) A molded article obtained by injection molding the resin composition according to Item 1,
Item 7) The molded article according to Item 6, wherein the crystallization temperature Tci at a temperature rise (10 ° C / min temperature rise) measured by a differential scanning calorimeter is 140 to 150 ° C, and
Item 8) The molded article according to Item 7, wherein the Tci is lower by 5 to 15 ° C than the molded article in which the polyhexamethylene terephthalate (B) is not blended.
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 containing 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% based on all dicarboxylic acid components. 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'-diphenylsulfonedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, , 3-phenylenedioxydiacetic acid and structural isomers thereof, dicarboxylic acids such as malonic acid, succinic acid, adipic acid and derivatives thereof, and oxyacids such as p-hydroxybenzoic acid and glycolic acid and derivatives thereof. it can.
[0013]
In addition, the main diol component refers to a component exceeding 90 mol% based on all diol components. Therefore, 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 the diol component other than ethylene glycol include aliphatic glycols such as 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, pentamethylene glycol, neopentyl glycol, and fats such as cyclohexanedimethanol. Aromatic dihydroxy compound derivatives such as cyclic glycol, bisphenol A and 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. You may. A raw material containing terephthalic acid or an ester-forming derivative thereof and ethylene glycol is subjected to an esterification reaction or a transesterification reaction in the presence of an esterification catalyst or a transesterification catalyst, and bis (β-hydroxyethyl) terephthalate and / or Oligomer. Thereafter, in the presence of a polycondensation catalyst and a stabilizer, melt polycondensation is performed at a high temperature under reduced pressure to obtain a polymer.
[0016]
The esterification catalyst does not need to be particularly used 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 usage 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 all the polymerization raw materials.
[0017]
As the polycondensation catalyst, it is necessary to use germanium dioxide from the viewpoint of satisfying the color tone, transparency, and food safety, and the amount of the addition is preferably 20 to 20% by weight of the germanium element with respect to the weight of all dicarboxylic acid components. It is 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.Examples of the stabilizer include phosphoric esters such as trimethyl phosphate, triethyl phosphate and triphenyl phosphate, phosphites such as triphenyl phosphite and trisdodecyl phosphite, and methyl acid phosphate. Phosphorus compounds such as dibutyl phosphate, monobutyl phosphate acidic phosphate, phosphoric acid, phosphorous acid, hypophosphorous acid, and polyphosphoric acid are preferred.
[0019]
The amount of the stabilizer to be added is generally 10 to 1000 ppm, preferably 20 to 500 ppm, as the weight of the phosphorus element in the stabilizer with respect to all the polymerization raw materials.
[0020]
The supply of the catalyst and the stabilizer can be performed at the time of preparing the raw material slurry or at any time of the esterification reaction or the transesterification reaction. It may be supplied at an early stage of the polycondensation reaction step.
[0021]
The reaction temperature of the esterification reaction or transesterification reaction is usually from 240 to 280 ° C, and the reaction pressure is from normal pressure to 0.3 Mpa.
[0022]
The reaction temperature of the polycondensation reaction is usually from 250 to 300 ° C, and the reaction pressure is usually from 60 to 0.1 Kpa.
[0023]
The esterification reaction, 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 above melt polymerization is subjected to solid phase polymerization. At this time, it is preferable that the polymer chip is preliminarily crystallized at a temperature lower than the temperature at which the solid-phase polymerization is performed.
[0026]
In the pre-crystallization step, the amorphous polymer chips are usually kept at a temperature of 120 to 200 ° C., preferably 130 to 180 ° C., always under a fluidized state so that fusion due to heat generated by crystallization of the chips does not occur. Crystallization in one or more stages for at least 15 minutes or more.
[0027]
The following solid-state polymerization step comprises at least one step, 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 a normal pressure to 0.1 Mpa. And is carried out under a flow of an inert gas such as nitrogen, argon, carbon dioxide or the like.
[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, more preferably 10 to 25 hours.
[0029]
The limiting viscosity number of the polymer obtained by solid-state 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 polyethylene terephthalate (A) is 0.7 to 2.0 wt%, preferably 1.0 to 1.5 wt%, based on all diol components constituting polyethylene terephthalate. If it is less than 0.7 wt%, the transparency of the bottle body after molding is reduced, and if it is more than 2.0 wt%, the heat resistance is reduced 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 raw material for polymerization.Because ethylene glycol used as a main raw material partially produces diethylene glycol as a by-product, The amount of production may be adjusted.
[0032]
In order to reduce mold contamination during bottle molding, the content of the oligomer 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 taste and smell of the bottle filling, the content of acetaldehyde 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-mentioned solid-phase polymerization, and the above-mentioned contents can be satisfied by adjusting the intrinsic viscosity number, the solid-phase polymerization time, and the temperature time of the polymer after the melt polymerization.
[0035]
The concentration of the terminal carboxyl group of the polyethylene terephthalate (A) is preferably 15 to 25 eq / ton. Within this range, oligomers can be sufficiently reduced by relatively short-time solid-phase polymerization.
[0036]
[Polyhexamethylene terephthalate (B)]
Polyhexamethylene terephthalate (B) is a polyester containing terephthalic acid as a main dicarboxylic acid component and hexamethylene glycol as a main diol component.
[0037]
The main dicarboxylic acid component means a component of 80 mol% or more, preferably 90 mol% or more of all dicarboxylic acid components. Further, the main diol component means a component of 80 mol% or more, preferably 90 mol% or more of all diol components.
[0038]
In order to obtain solubility in a solvent, polyhexamethylene terephthalate (B) contains 1 to 10 mol of an isophthalic acid component having a sulfonic acid metal base (hereinafter may be abbreviated as IAS) per total dicarboxylic acid component. %, More preferably 3 to 5 mol%, as a copolymerization component.
[0039]
Examples of IAS include 5-lithium sulfoisophthalic acid, 5-sodium sulfoisophthalic acid, and 5-potassium sulfoisophthalic acid, with 5-sodium sulfoisophthalic acid being preferred.
[0040]
These may be derived from derivatives. As the derivative, for example, an ester can be used, and examples thereof include a methyl ester, an ethyl ester, a propyl ester, and a butyl ester, and among them, a methyl ester is preferable.
[0041]
In the polyhexamethylene terephthalate (B), a dicarboxylic acid component and / or a diol component may be substituted with a copolymer component as long as the effect of promoting crystallization is not hindered. This is a component of 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]
Examples of the dicarboxylic acid component usable as the copolymerization component include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, Examples thereof 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 usable as the copolymerization component include aliphatic glycols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, pentamethylene glycol and neopentyl glycol, and cyclohexane. Examples include alicyclic glycols such as dimethanol, and aromatic dihydroxy compound derivatives such as bisphenol A and bisphenol S.
[0044]
The raw material containing the above terephthalic acid or its ester-forming derivative and hexamethylene glycol is subjected to an esterification reaction or a transesterification reaction in the presence of an esterification catalyst or a transesterification catalyst to give a hexamethylene terephthalate monomer (1 ) To an oligomer (a polymer having a low degree of polymerization), and then melt polycondensation at a high temperature under reduced pressure in the presence of a polycondensation catalyst and, if necessary, a stabilizer to convert polyhexamethylene terephthalate. Obtainable.
[0045]
At this time, the esterification catalyst does not need to be particularly used 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, but a titanium compound is preferable in terms of reactivity. The amount of addition is preferably 20 to 80 ppm, more preferably 30 to 50 ppm, as the weight of titanium element with respect to the weight of all dicarboxylic acid components.
[0047]
The supply of the catalyst and the stabilizer can be performed at the time of preparing the raw material slurry or at any time of the esterification reaction or the transesterification reaction. It may be supplied at an early stage of the polycondensation reaction step.
[0048]
The reaction temperature of the esterification reaction or transesterification reaction is usually from 210 to 220 ° C, and the reaction pressure is from normal pressure to 0.3 Mpa.
[0049]
The reaction temperature of the polycondensation reaction is usually from 240 to 270 ° C, and the reaction pressure is usually from 60 to 0.1 Kpa.
[0050]
The esterification reaction, transesterification reaction, and polycondensation reaction may be performed in one stage, or may be performed in two or more stages.
[0051]
In this way, a polymer having an intrinsic viscosity of usually 0.30 to 0.70 dl / g is obtained by melt polycondensation. The polymer is formed into chips by a conventional method.
[0052]
[Formulation method]
The polyhexamethylene terephthalate (B) is blended at a ratio of 1 to 100 ppm, preferably 1 to 50 ppm, more preferably 5 to 50 ppm, based on the polyethylene terephthalate (A). If it is less than 1 ppm, there is no effect of improving the crystallinity, and if it exceeds 100 ppm, fusion of the chips occurs when the chips are dried, or a drop of the chips occurs during molding, which hinders the stability of the molding. The transparency of the resulting bottle container is reduced.
[0053]
The polyhexamethylene terephthalate (B) is preferably blended by attaching an aqueous dispersion containing the polyhexamethylene terephthalate (B) at a concentration of 0.05 to 2 wt% to a polyethylene terephthalate (A) chip.
[0054]
If the polyhexamethylene terephthalate (B) is not blended in the form of an aqueous dispersion, but is blended, for example, with a powder blend, the blend becomes non-uniform and it is difficult to stably obtain the effect of promoting crystallization. Absent.
[0055]
The concentration of the polyhexamethylene terephthalate (B) in the aqueous dispersion is usually 0.05 to 2% by weight, preferably 0.1 to 1% by weight, more preferably 0.2 to 0.5% by weight. If the content 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 reduced by drying after the treatment, which is not preferable. If it exceeds 2 wt%, it is difficult to uniformly attach the solution to the polyethylene terephthalate chip, which is not preferable.
[0056]
As a method for converting polyhexamethylene terephthalate (B) into an aqueous dispersion, a method in which polyhexamethylene terephthalate (B) is dissolved in an organic solvent capable of dissolving and replaced with water is preferable. The concentration of polyhexamethylene terephthalate (B) may be adjusted by adjusting the amount of water used for substitution, or may be adjusted by obtaining a high-concentration aqueous dispersion once, adding water and diluting as appropriate. Good.
[0057]
As a method of attaching the aqueous dispersion of polyhexamethylene terephthalate (B) to the chip of polyethylene terephthalate (A), for example, a spray method or a dipping method can be applied.
[0058]
The mixing of the polyhexamethylene terephthalate (B) is performed during the period from the end of the melt polymerization of the polyethylene terephthalate (A) to the point of molding the molded body, for example, at the time of cutting into chips after the melt polymerization, or at the time of solid-phase polymerization. This can be done at a point in time, before drying of the molding. From the viewpoint of suppressing deterioration of the polyethylene terephthalate (A) due to heat, a point after the solid phase polymerization is preferable.
[0059]
When an aqueous dispersion is used for blending the polyhexamethylene terephthalate (B), it is preferable to dry and remove water during the period from the adhesion treatment of the aqueous dispersion to the molding, but if the molding is performed with a vent, There is no particular 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 lower by 5 to 15 ° C than a molded product in which polyhexamethylene terephthalate (B) is not blended (for example, a molded product of polyethylene terephthalate (A)).
[0061]
When Tci is less than 140 ° C., when the body of the preform obtained by molding is heated for blow molding, whitening due to crystallization easily occurs, and the shoulder and the body are whitened and transparent. In some cases, the heat resistance may be impaired, and heat resistance may be imparted, so that heating becomes difficult, resulting in insufficient heat resistance, which is not preferable. When Tci exceeds 150 ° C., the mouth portion is heated and crystallized to a desired degree of crystallinity, so that long-time heating is required and productivity is reduced, and the mouth crystallization equipment must be enlarged. Will be. By satisfying the above condition of Tci, the crystallinity and transparency of the molded article and the heat resistance imparted to the bottle can all be satisfied at the same time.
[0062]
[Production method of molded article]
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 once formed by injection molding or extrusion molding, and is heated as it is or after processing the mouth and bottom, 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 and the nozzle of the molding machine) is, for example, 260 to 315 ° C, preferably 275 to 295 ° C. The stretching temperature is equal to or higher than the glass transition temperature of polyethylene terephthalate, and is usually 70 to 130 ° C. The stretching 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 when heat filling is required, such as fruit juice drinks, oolong tea, etc., it is generally heat-fixed in a heated blow mold and further used with 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. Alternatively, a method may be used in which a bottle larger than the final shape is formed, and the body is crystallized by being shrunk by heating, followed by blow molding in a mold having the final shape to obtain a bottle of the product.
[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
The limiting viscosity number (hereinafter sometimes abbreviated as IV) is obtained by measuring a fixed amount of a sample cut out from a portion corresponding to the top surface of a bottle or a tip of a preform (synonymous with a plug). , 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 raising the temperature (hereinafter, may be abbreviated as Tci) is measured by a differential scanning calorimeter (DSC Model 2200 manufactured by DuPont) for a sample cut from a portion corresponding to the top surface of the bottle opening of the preform. The crystallization temperature Tci (temperature at the top of the crystallization peak) at the time of temperature rise measured at a temperature rise rate of 10 ° C./min was measured.
[0069]
(3) Haze
A sample (330 μm thickness) cut out from the bottle body to a size of 50 mm × 50 mm was measured with a Nippon Denshoku Industries Color and color difference meter MODEL1001DP.
[0070]
(4) Acetaldehyde content
The content of acetaldehyde (hereinafter may be abbreviated as AA) was measured by freeze-crushing a sample, charging the sample in a vial bottle, keeping at 150 ° C. for 60 minutes, and using headspace gas chromatography manufactured by Hitachi.
[0071]
(5) Amount of oligomer
The oligomer (hereinafter sometimes abbreviated as Cy-3) content is determined by gel-permeation chromatography (gel permeation chromatography) on a sample obtained by weighing a fixed amount of a sample, dissolving the sample in hexafluoroisopropanol, and diluting the sample with chloroform to a certain concentration. Waters 484).
[0072]
(6) Polyhexamethylene terephthalate (B) concentration of resin composition
The weight ratio of polyhexamethylene terephthalate (B) to the resin composition was calculated. Specifically, it is a value obtained by dividing the weight of the actually blended polyhexamethylene terephthalate (B) by the weight of the resin composition. The weight of the actually distributed polyhexamethylene terephthalate (B) 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
It was quantified by fluorescent X-ray (Rigaku Denki 3270E).
[0074]
(8) Diethylene glycol content
The content of diethylene glycol (hereinafter sometimes abbreviated as DEG) was determined by decomposing a sample with hydrazine and measuring the content of the sample by gas colromatography.
[0075]
(9) Production of polyhexamethylene terephthalate (B) and production of aqueous dispersion
With 100 parts of dimethyl terephthalate, 5 parts of 5-sodium sulfoisophthalic acid dimethyl ester and 63 parts of hexamethylene glycol, 0.027 part of tetra-t-butoxytitanium is used as a catalyst, and methanol as a by-product is distilled out of the system; The transesterification reaction was carried out while heating to 220 ° C., and then the reaction product was subjected to a polycondensation reaction under high temperature and high vacuum to obtain polyhexamethylene terephthalate (B) having an intrinsic viscosity of 0.60. I made it. The obtained chip-shaped polyhexamethylene terephthalate (B) was dissolved in tetrahydrofuran, and then replaced with water to obtain an aqueous dispersion having a polyhexamethylene terephthalate (B) concentration of 0.3% by weight.
[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 an esterification reaction is performed at 275 ° C. for 4 hours under normal pressure, and water as a by-product flows out of the system. The reaction was carried out to an esterification reaction rate of 97% to form an oligomer having a degree of polymerization of 5 to 10, which was added to an ethylene glycol solution of trimethylphosphoric acid (phosphorus concentration (weight ratio of phosphorus element in the solution) of 5.5 wt%). .017 parts and 0.38 part of an ethylene glycol solution of germanium dioxide (concentration of 1 wt% of germanium dioxide) were added, and polycondensation was performed at 277 ° C. for 2 hours under a reduced pressure of 2000 Pa for 1 hour and then at a reduced pressure of 133 Pa. .
[0077]
The produced polymer was drawn out in a strand shape from a draw-out opening provided directly at the bottom of the polycondensation bath directly connected to the cooling water bath, cooled with water, and then cut into chips to obtain polymer chips.
[0078]
After the obtained polymer chips were crystallized by a stirring fluidized crystallizer, they were dried at 140 ° C. for 3 hours under a nitrogen flow, then transferred to a packed column type solid-state polymerization tower, and heated at 215 ° C. for 22 hours under a nitrogen flow. Solid-state polymerization produced a chip-like polyethylene terephthalate (A).
[0079]
After spraying a predetermined amount of an aqueous dispersion of polyhexamethylene terephthalate (B) (concentration: 0.3 wt%) on the obtained chip-shaped polyethylene terephthalate (A), the mixture was dried at 140 ° C. for 3 hours, and then dried. Chips of a resin composition of polyethylene terephthalate having a methylene terephthalate (B) concentration of 20 ppm were obtained. Table 1 shows the results.
[0080]
The obtained resin composition chips were dried at 160 ° C. for 5 hours with a vacuum dryer, and then, at an injection molding machine (M-100DM manufactured by Meiki Seisakusho Co., Ltd.), the cylinder temperature was 275 ° C., and the screw rotation number was 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]
Furthermore, 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 dispersion was evaluated. Table 2 shows the results.
[0082]
Subsequently, only the part corresponding to the mouth of the bottle of the preform was crystallized at 160 ° C. for one minute by a plug crystallization apparatus (infrared heater), and then the surface temperature of the preform was increased to about 110 ° C. by infrared rays. Preheated by heater, blow pressure 5-40kg / cm ² Then, stretch blow molding was performed using 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 of the obtained bottle was measured. Table 2 shows the results.
[0083]
Furthermore, in order to confirm the molding stability of the bottles, appearance defects were confirmed for ten bottles.
[0084]
[Table 1]

[0085]
[Table 2]

[0086]
[Examples 2 to 5]
A resin composition chip was obtained in the same manner as in Example 1, except that the concentration of the aqueous dispersion of polyhexamethylene terephthalate (B) and the amount of polyhexamethylene terephthalate (A) were changed as shown in Table 1. Was. The obtained resin composition chip was injection molded into a preform, and the bottle was blow molded. The obtained preform and bottle were evaluated. Table 2 shows the results.
[0087]
[Comparative Example 1]
The same operation as in Example 1 was carried out without blending polyhexamethylene terephthalate (B). The results are shown in Tables 1 and 2.
[0088]
[Comparative Example 2]
The procedure was performed in the same manner as in Example 1 except that the amount of polyhexamethylene terephthalate (B) was changed. The results are shown in Tables 1 and 2.
[0089]
[Comparative Example 3]
The chip-like polyhexamethylene terephthalate (B) is pulverized, passed through a 100-Mesh sieve, and turned into powder remaining on the 200-Mesh sieve. (A), and 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】
ADVANTAGE OF THE INVENTION According to this invention, while being excellent in transparency, mechanical strength, heat resistance, and flavor, while ensuring sufficient dimensional accuracy of the mouth, there is little variation in crystallinity, excellent production stability, and promotion of crystallinity. The present invention can provide a finished polyester resin composition for a bottle container.

Claims (8)

Polyhexamethylene terephthalate (B) is added to polyethylene terephthalate (A) having an intrinsic viscosity of 0.70 to 0.90 by polycondensation reaction using a germanium compound as a catalyst. A resin composition containing-100 ppm. Polyhexamethylene terephthalate (B) is added to polyethylene terephthalate (A) having an intrinsic viscosity of 0.70 to 0.90 by polycondensation reaction using a germanium compound as a catalyst. A method for producing a resin composition, which is blended so as to be 100 ppm. The polyhexamethylene terephthalate (B) is compounded by attaching an aqueous dispersion containing the polyhexamethylene terephthalate (B) at a concentration of 0.05 to 2% by weight to a polyethylene terephthalate (A) chip. 3. The method for producing the resin composition according to 2. A resin composition produced by the production method according to claim 3. Polyethylene terephthalate (A) is produced by solid phase polymerization and contains 0.7 to 2.0 wt% of a diethylene glycol component as a component of the polymer, 0 to 0.5 wt% of an oligomer, and 0 to 5 ppm of acetaldehyde. The resin composition according to claim 1, wherein: A molded article obtained by injection molding the resin composition according to claim 1. The molded article according to claim 6, wherein the crystallization temperature Tci at a temperature rise (10 ° C / min temperature rise) measured by a differential scanning calorimeter is 140 to 150 ° C. The molded article according to claim 7, wherein Tci is lower by 5 to 15C than the molded article in which the polyhexamethylene terephthalate (B) is not blended.