JP2007321091A - Polyester composition and polyester molded article comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester composition which comprises a thermoplastic polyester using an antimony compound as a catalyst, and a partially aromatic polyamide, prevents an increase in darkness, and is excellent in transparency, flavor retainability, and thermal stability, or in transparency, flavor retainability, thermal stability and gas barrier property, and to provide a polyester molded article comprising the same. <P>SOLUTION: The polyester composition comprising 99.9 wt.% of a polyester containing an antimony compound, and 0.1 to 30 wt.% of a partial aromatic polyamide is characterized in that the content (P1) of phosphorus atom in the partial aromatic polyamide and the content (A) of the partial aromatic polyamide satisfies the following expression (1) : 0<(P1×A)≤500 (1), wherein P1: the content (ppm) of phosphorus atom originated from a phosphorus compound detected in a specific structure in the partial aromatic polyamide; A : the content (ppm) of the partial aromatic polyamide in the polyester composition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to materials for hollow molded containers such as beverage bottles, molded products such as sheets, films and monofilaments, and polyester molded products such as coatings coated on substrates such as paper and films. As a polyester composition suitably used as an antimony compound as a catalyst, and a polyester composition that suppresses an increase in darkening from a partially aromatic polyamide and a color tone, transparency, flavor retention and thermal stability comprising the polyester composition The present invention relates to a polyester molded article having excellent gas barrier properties.

Thermoplastic polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”) are excellent in both mechanical properties and chemical properties, and thus have high industrial value, such as fibers, films and sheets. Widely used as bottles, etc. Furthermore, since thermoplastic polyester is excellent in heat resistance, transparency, and gas barrier properties, it is particularly suitable as a material for molded articles such as beverage filling containers such as juices, soft drinks, and carbonated drinks.
For example, such a thermoplastic polyester is supplied to a molding machine such as an injection molding machine to form a preform for a hollow molded body, and the preform is inserted into a mold having a predetermined shape and subjected to stretch blow molding. Generally, the body portion of the rear bottle is heat-treated (heat set) to be formed into a hollow molded container, and further, the cap portion of the bottle is heat-treated (crystallization of the plug portion) as necessary.

  However, PET contains acetaldehyde (hereinafter sometimes abbreviated as AA) as a by-product during melt polycondensation. In addition, PET produced acetaldehyde by thermal decomposition when thermoforming a molded body such as a hollow molded body, and the acetaldehyde content in the material of the obtained molded body was increased, and the hollow molded body was filled. Affects the flavor and odor of beverages.

In order to solve such a problem, various measures have heretofore been taken in order to reduce the acetaldehyde content in the thermoplastic polyester molded body. In general, a method using a thermoplastic polyester in which the AA content is reduced by solid-phase polymerization of a melt-polycondensed prepolymer, and AA generation at the time of molding using a copolymer thermoplastic polyester having a lower melting point A method for lowering the temperature, a method for reducing the molding temperature during thermoforming as much as possible, a method for reducing the shear stress during thermoforming as much as possible, and the like are known.
In recent years, thermoplastic polyester containers mainly made of polyethylene terephthalate have come to be used as containers for low flavor beverages such as mineral water and oolong tea. In the case of such beverages, these beverages are generally heat-filled or sterilized by heating after filling, but these containers can be obtained only by reducing the AA content in the thermoplastic polyester molded material by the above method. It has been found that the flavor and odor of the contents are not improved, and there is a need for improvement.

  As a technique for solving such a problem, a method using a polyester composition in which a metaxylylene group-containing polyamide resin is added in an amount of 0.05 to 1 part by weight with respect to 100 parts by weight of a thermoplastic polyester resin (for example, Patent Document 1) and polyester containers (for example, see Patent Document 2) made of a polyester composition containing thermoplastic polyamide and a specific polyamide whose terminal amino group concentration is regulated within a certain range have been proposed. . However, it has also been found that the color tone and variation of molded articles such as polyester containers obtained by these inventions are not good, and the flavor and smell of the beverage as the contents may be insufficient. It was.

On the other hand, a thermoplastic polyester molded body mainly composed of PET is quite excellent in terms of gas barrier properties, but a hollow molded body for contents containing a compound very sensitive to oxygen such as vitamin C. As a result, it has been found to be unsatisfactory, and improvements are required.
As a technique for solving such a problem, we have made a thermoplastic polyester hollow molded body containing 1 to 100 parts by weight of a metaxylylene group-containing polyamide resin with respect to 100 parts by weight of a thermoplastic polyester resin (see, for example, Patent Document 3). ) Was proposed. However, the color tone of the hollow molded body made of such a polyester composition may be strong yellowish or gray, and the variation thereof is not good.
In addition, the polyester composition and molded product obtained by mixing and molding a metaxylylene group-containing polyamide with a thermoplastic polyester containing an antimony compound may greatly increase darkening that may be caused by the precipitation of metal antimony. Therefore, there is a drawback that the commercial value of the molded body and packaging container for food use and the like where the appearance is important is greatly reduced. In order to solve this problem, a polyester resin composition in which the concentration of a phosphorus compound derived from a polyamide resin is regulated (for example, see Patent Document 4), or a polyamide in which the content ratio of a specific metal compound such as an alkali metal and a phosphorus compound is regulated. A polyester composition of a resin and a thermoplastic polyester containing an antimony compound has been proposed (see, for example, Patent Document 5), but darkening is incomplete and improvement is required.

Japanese Examined Patent Publication No. 6-6661 Japanese Examined Patent Publication No. 4-71425 Japanese Examined Patent Publication No. 4-54702 JP 2002-332397 A JP 2004-131723 A

  The present invention is to solve the above-mentioned problems of the prior art, comprising a thermoplastic polyester and a partially aromatic polyamide using an antimony compound as a catalyst, and suppressing the increase in darkening, transparency and flavor retention. Another object of the present invention is to provide a polyester composition excellent in heat stability, transparency, flavor retention, heat stability, and gas barrier properties, and a polyester molded article comprising the same.

  The present inventors have used a polyester composition composed of 99.9 to 70% by weight of a thermoplastic polyester containing an antimony compound and 0.1 to 30% by weight of a partially aromatic polyamide, and has transparency and flavor retention. In addition, as a result of studying a polyester molded article excellent in transparency, flavor retention and gas barrier properties, a partial aromatic polyamide compounded in the polyester composition contains a phosphorus atom derived from a phosphorus compound having a specific structure The present invention was completed by finding that the amount and the content of the partially aromatic polyamide are related to the occurrence of darkening in the polyester composition.

That is, the polyester composition of the present invention is a polyester composition comprising 99.9 to 70% by weight of a thermoplastic polyester containing an antimony compound and 0.1 to 30% by weight of a partially aromatic polyamide. The polyester composition is characterized in that the phosphorus atom content (P1) in the aromatic polyamide and the content (A) of the partially aromatic polyamide in the polyester composition satisfy the following formula (1).
(However, P1 is a phosphorus compound-derived phosphorus detected in the structure of the following structural formula (formula 1) when the partial aromatic polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added followed by structural analysis. Atomic content.)

(Wherein R ₁ and R ₂ are hydrogen, alkyl group, aryl group, cycloalkyl group or arylalkyl group, and X ₁ is hydrogen)
0 <(P1 × A) ≦ 500 (1)
In formula (1),
P1: Content of phosphorus atom derived from phosphorus compound detected by the above structural formula (formula 1) in partially aromatic polyamide (ppm)
A: Content (% by weight) of partially aromatic polyamide in the polyester composition

The polyester composition of the present invention is a polyester composition comprising 99.9 to 70% by weight of a thermoplastic polyester containing an antimony compound and 0.1 to 30% by weight of a partially aromatic polyamide, The content (P1), the phosphorus atom content (P2) in the partially aromatic polyamide, and the content (A) of the partially aromatic polyamide in the polyester composition satisfy the following formula (2): A polyester composition.
(However, P2 is a phosphorus compound-derived phosphorus detected by the structure of the following structural formula (formula 2) when the partial aromatic polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added and then the structure is analyzed. Atomic content.)

(Wherein R ₃ is hydrogen, an alkyl group, an aryl group, a cycloalkyl group or an arylalkyl group, X ₂ and X ₃ are hydrogen)
0 <(P1 + P2) × A ≦ 900 (2)
In formula (2),
P1: Content of phosphorus atom derived from phosphorus compound detected by the above structural formula (formula 1) in partially aromatic polyamide (ppm)
P2: phosphorus atom content (ppm) derived from the phosphorus compound detected by the above structural formula (formula 2) in the partially aromatic polyamide
A: Content (% by weight) of partially aromatic polyamide in the polyester composition

In this case, the solution haze of the thermoplastic polyester can be 10.0% or less.
In this case, the content of antimony atoms remaining in the thermoplastic polyester can be 100 to 400 ppm.
In this case, the content of phosphorus atoms remaining in the partially aromatic polyamide can be 70 to 400 ppm.
In this case, the acetaldehyde content of the molded product obtained by injection molding the polyester composition can be 15 ppm or less.
In this case, it can be set as the polyester molded object using the said polyester composition.
In this case, the polyester molded body of the present invention can be any one of a hollow molded body, a sheet-like material, and a stretched film obtained by stretching the sheet-like material in at least one direction.
Moreover, in this case, it can be a coating obtained by melt-extruding the polyester composition on a substrate.

  Here, the hollow molded body is an unstretched hollow molded body or a stretched hollow molded body stretched in at least one direction, and the coating is a melted polyester composition on a certain substrate. A thin film-like product formed by extrusion molding or a film-like product bonded by heat bonding or an adhesive.

  According to the polyester composition of the present invention, there is no darkening, and a polyester molded article excellent in transparency, flavor retention and thermal stability, or transparency, flavor retention, thermal stability and gas barrier properties is obtained. In addition, as described above, the polyester molded body of the present invention is very suitable as a molded body for beverages such as soft drinks.

Hereinafter, embodiments of the polyester composition of the present invention and the polyester molded body comprising the same will be described in detail.
(Thermoplastic polyester)
The thermoplastic polyester used in the present invention is a crystalline thermoplastic polyester obtained mainly from an aromatic dicarboxylic acid component and a glycol component, and more preferably, the aromatic dicarboxylic acid unit is 85 mol% or more of the acid component. The thermoplastic polyester is particularly preferably 90 mol% or more, and most preferably a thermoplastic polyester containing aromatic dicarboxylic acid units of 95 mol% or more of the acid component.

  Examples of the aromatic dicarboxylic acid component constituting the thermoplastic polyester used in the present invention include fragrances such as terephthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, and diphenoxyethanedicarboxylic acid. Group dicarboxylic acids and functional derivatives thereof.

  Examples of the glycol component constituting the thermoplastic polyester used in the present invention include aliphatic glycols such as ethylene glycol, 1,3-trimethylene glycol and tetramethylene glycol, and cyclohexanedimethanol. And alicyclic glycols such as

  Examples of the acid component used as a copolymerization component in the thermoplastic polyester include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid, and the like. Aromatic dicarboxylic acids, oxyacids such as p-oxybenzoic acid and oxycaproic acid and their functional derivatives, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, succinic acid, glutaric acid and dimer acid and their functional derivatives And alicyclic dicarboxylic acids such as hexahydroterephthalic acid, hexahydroisophthalic acid and cyclohexanedicarboxylic acid, and functional derivatives thereof.

  Examples of the glycol component used as a copolymerization component in the thermoplastic polyester include ethylene glycol, 1,3-trimethylene glycol, tetramethylene glycol, diethylene glycol, neopentyl glycol. Aliphatic glycols such as cyclohexane dimethanol, etc., 1,3-bis (2-hydroxyethoxy) benzene, bisphenol A, alkylene oxide adducts of bisphenol A, etc. And polyalkylene glycols such as aromatic glycol, polyethylene glycol and polybutylene glycol.

  Furthermore, polyfunctional compounds such as trimellitic acid, trimesic acid, pyromellitic acid, tricarballylic acid, glycerin, pentaerythritol, trimethylolpropane, etc. are used within the range in which the thermoplastic polyester is substantially linear. It may be polymerized or a monofunctional compound such as benzoic acid or naphthoic acid may be copolymerized.

The thermoplastic polyester according to the present invention is preferably a polyester containing 70 mol% or more of a structural unit derived from an aromatic dicarboxylic acid and at least one glycol selected from aliphatic glycols having 2 to 4 carbon atoms.
A preferred example of the thermoplastic polyester used in the present invention is a thermoplastic polyester whose main repeating unit is composed of ethylene terephthalate, and more preferably contains 85 mol% or more of ethylene terephthalate units, It is a linear copolymer thermoplastic polyester containing isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedimethanol and the like as a component, and particularly preferably a line containing 95 mol% or more of ethylene terephthalate units. It is a thermoplastic polyester.

  Examples of these linear thermoplastic polyesters include polyethylene terephthalate (hereinafter abbreviated as PET), poly (ethylene terephthalate-ethylene isophthalate) copolymer, poly (ethylene terephthalate-ethylene isophthalate-ethylene-2,6-naphthalate). ) Copolymer, poly (ethylene terephthalate-1,4-cyclohexanedimethylene terephthalate) copolymer, poly (ethylene terephthalate-ethylene-2,6-naphthalate) copolymer, poly (ethylene terephthalate-dioxyethylene terephthalate) Examples thereof include a copolymer, a poly (ethylene terephthalate-1,3-propylene terephthalate) copolymer, and a poly (ethylene terephthalate-ethylenecyclohexylene dicarboxylate) copolymer.

  Another preferred example of the thermoplastic polyester used in the present invention is a thermoplastic polyester whose main repeating unit is composed of ethylene-2,6-naphthalate, and more preferably ethylene-2,6-naphthalene. -A linear thermoplastic polyester containing 85 mol% or more of a toe unit, particularly preferably a linear thermoplastic polyester containing 95 mol% or more of an ethylene-2,6-naphthalate unit.

  Examples of these linear thermoplastic polyesters include polyethylene-2,6-naphthalate (PEN), poly (ethylene-2,6-naphthalate-ethylene terephthalate) copolymer, poly (ethylene-2,6-naphthalate-ethylene). Isophthalate) copolymer, poly (ethylene-2,6-naphthalate-dioxyethylene-2,6-naphthalate) copolymer, and the like.

  Furthermore, other preferable examples of the thermoplastic polyester according to the present invention are thermoplastic polyesters whose main structural unit is composed of 1,3-propylene terephthalate, and more preferably 1,3-propylene terephthalate. A linear thermoplastic polyester containing 70 mol% or more of talate units, particularly preferably a linear thermoplastic polyester containing 90 mol% or more of 1,3-propylene terephthalate units.

  Examples of these linear thermoplastic polyesters include polypropylene terephthalate (PTT), poly (1,3-propylene terephthalate-1,3-propylene isophthalate) copolymer, poly (1,3-propylene terephthalate-1,4). -Cyclohexane dimethylene terephthalate) copolymer, poly (1,3-propylene terephthalate-1,3-propylene-2,6-naphthalate) copolymer, and the like.

  Other preferable examples of the thermoplastic polyester according to the present invention other than those described above include thermoplastic polyesters in which the main structural unit is 1,3-propylene-2 and 6-naphthalate, and the main structural unit is in butylene-2. , 6-naphthalate thermoplastic polyester.

  The thermoplastic polyester according to the present invention can basically be produced by a conventionally known melt polycondensation method or melt polycondensation method-solid phase polymerization method. The melt polycondensation reaction may be performed in one stage or may be performed in multiple stages. These may be comprised from a batch-type reaction apparatus, and may be comprised from the continuous-type reaction apparatus. The melt polycondensation step and the solid phase polymerization step may be operated continuously or may be operated separately. Hereinafter, an example of a preferable continuous production method for the polyester composition of the present invention will be described using polyethylene terephthalate (PET) as an example, but the present invention is not limited thereto. That is, in the case of PET, terephthalic acid, ethylene glycol and, if necessary, the above copolymerization component are directly reacted to distill off water and esterify, and then use an antimony compound as a polycondensation catalyst under reduced pressure. After direct esterification using polycondensation, or after reacting dimethyl terephthalate with ethylene glycol and, if necessary, the above copolymerization component in the presence of a transesterification catalyst to distill off methyl alcohol and transesterify It is produced by a transesterification method in which polycondensation is carried out mainly under reduced pressure using an antimony compound as a polycondensation catalyst. As the polycondensation catalyst, one or more compounds selected from a germanium compound, a titanium compound or an aluminum compound can be used in addition to the antimony compound.

  Furthermore, in order to increase the intrinsic viscosity of the thermoplastic polyester and reduce the content of aldehydes such as acetaldehyde and the content of cyclic ester trimer, solid phase polymerization may be performed.

First, when a low polymer is produced by an esterification reaction, 1.02 to 2.0 mol, preferably 1.03 to 1.6 mol of ethylene glycol is added to 1 mol of terephthalic acid or an ester derivative thereof. The contained slurry is prepared and continuously supplied to the esterification reaction step.
In the esterification reaction, water or alcohol produced by the reaction is removed out of the system by a rectification column under conditions where ethylene glycol is refluxed using a multistage apparatus in which at least two esterification reactors are connected in series. While implementing. The temperature of the first stage esterification reaction is 240 to 270 ° C., preferably 245 to 265 ° C., and the pressure is 0.2 to 3 kg / cm ² G, preferably 0.5 to ² kg / cm ² G. The temperature of the esterification reaction in the final stage is usually 250 to 280 ° C, preferably 255 to 275 ° C, and the pressure is usually 0 to 1.5 kg / cm ² G, preferably 0 to 1.3 kg / cm ² G. . When carried out in three or more stages, the reaction conditions for the esterification reaction in the intermediate stage are conditions between the reaction conditions for the first stage and the reaction conditions for the final stage. The increase in the reaction rate of these esterification reactions is preferably distributed smoothly at each stage. Ultimately, it is desirable that the esterification reaction rate reaches 90% or more, preferably 93% or more. By these esterification reactions, low-order condensates having a molecular weight of about 500 to 5,000 are obtained.
When terephthalic acid is used as a raw material, the esterification reaction can be carried out without a catalyst by the catalytic action of terephthalic acid as an acid, but may be carried out in the presence of a polycondensation catalyst.

Also, tertiary amines such as triethylamine, tri-n-butylamine, benzyldimethylamine, quaternary ammonium hydroxides such as tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, trimethylbenzylammonium hydroxide, and lithium carbonate When a small amount of a basic compound such as sodium carbonate, potassium carbonate or sodium acetate is added, the proportion of dioxyethylene terephthalate component units in the main chain of polyethylene terephthalate is relatively low (5% relative to all diol components). Mol% or less).
Next, in the case of producing a low polymer by transesterification, 1.1 to 2.0 mol, preferably 1.2 to 1.5 mol of ethylene glycol was contained with respect to 1 mol of dimethyl terephthalate. The solution is prepared and continuously fed to the transesterification step.

  The transesterification reaction is carried out while removing methanol generated by the reaction outside the system using a rectification column under the condition that ethylene glycol is distilled back using an apparatus in which 1 to 2 transesterification reactors are connected in series. To do. The temperature of the first stage transesterification is 180 to 250 ° C, preferably 200 to 240 ° C. The temperature of the transesterification reaction at the final stage is usually 230 to 270 ° C., preferably 240 to 265 ° C. As transesterification catalysts, fatty acid salts such as zinc, magnesium, manganese, calcium, barium, carbonates, zinc, antimony , Oxides such as germanium are used. A low-order condensate having a molecular weight of about 200 to 500 is obtained by these transesterification reactions.

  The glycols such as aromatic dicarboxylic acid dimethyl ester, aromatic dicarboxylic acid or ethylene glycol which are the above starting materials include virgin dimethyl terephthalate derived from paraxylene, ethylene glycol derived from terephthalic acid or ethylene, of course. In addition, recovered raw materials such as dimethyl terephthalate, terephthalic acid, bishydroxyethyl terephthalate or ethylene glycol recovered from used PET bottles by chemical recycling methods such as methanol decomposition and ethylene glycol decomposition are also used as at least part of the starting material. I can do it. Needless to say, the quality of the recovered raw material must be refined to a purity and quality suitable for the intended use.

  Subsequently, the obtained low-order condensate is supplied to a multistage liquid phase condensation polymerization process. The polycondensation reaction conditions are as follows: the first stage polycondensation reaction temperature is 250 to 290 ° C., preferably 260 to 280 ° C., and the pressure is 500 to 20 Torr, preferably 200 to 30 Torr. The temperature is 265 to 300 ° C., preferably 275 to 295 ° C., and the pressure is 10 to 0.1 Torr, preferably 5 to 0.5 Torr. When carried out in three or more stages, the reaction conditions for the intermediate stage polycondensation reaction are conditions between the reaction conditions for the first stage and the reaction conditions for the last stage. The degree of increase in intrinsic viscosity achieved in each of these polycondensation reaction steps is preferably distributed smoothly. A single-stage polycondensation apparatus may be used for the polycondensation reaction.

  Antimony compounds used in the production of the thermoplastic polyester used in the present invention include antimony trioxide, antimony acetate, antimony tartrate, antimony tartrate, antimony oxychloride, antimony glycolate, antimony pentoxide, and triphenylantimony. Etc. The antimony compound has an antimony content (hereinafter sometimes abbreviated as S) in the produced polymer of 100 to 400 ppm, preferably 130 to 350 ppm, more preferably 150 to 300 ppm, and most preferably 170 to 250 ppm. It is desirable to add so that it becomes. If it is less than 100 ppm (0.82 mol per ton of polymer), the polycondensation rate becomes slow, resulting in a problem of economy. If it exceeds 400 ppm (3.28 mol per ton of polymer), the obtained polyester molded product In addition, the darkening of the polyester becomes intense, and the transparency of the polyester molded article obtained by excessively high crystallization speed is deteriorated. These antimony compounds are used as ethylene glycol solutions.

  In addition, it is preferable to further use a compound containing at least one metal atom selected from the group consisting of magnesium, calcium, cobalt, manganese, and zinc as the second metal compound. These are used in an amount of 0.1 to 3.0 mol, preferably 0.15, per ton of polymer as the content of these metals in the thermoplastic polyester (hereinafter sometimes abbreviated as Me). It is -2.5 mol, More preferably, it is the range of 0.2-2.0 mol. If the amount is less than 0.1 mol per ton of polymer, the precipitation of antimony metal in the thermoplastic polyester is increased, resulting in severe blackening. A polyester molded product from such a thermoplastic polyester, particularly a thick polyester molded product. Transparency becomes very bad and is a problem. On the other hand, if it exceeds 3.0 moles, the thermal stability of the thermoplastic polyester is poor, and the content of aldehydes such as acetaldehyde is increased, which may cause a problem in flavor.

The magnesium compound, calcium compound, cobalt compound, manganese compound, and zinc compound used for the production of the thermoplastic polyester used in the present invention can all be used as long as they are soluble in the reaction system.
Examples of the magnesium compound include lower fatty acid salts such as magnesium hydride, magnesium oxide, and magnesium acetate, alkoxides such as magnesium methoxide, and the like.
Examples of calcium compounds include lower fatty acid salts such as calcium hydride, calcium hydroxide and calcium acetate, and alkoxides such as calcium methoxide.

Examples of the cobalt compound include lower fatty acid salts such as cobalt acetate, organic acid salts such as cobalt naphthenate and cobalt benzoate, chlorides such as cobalt chloride, and cobalt acetylacetonate.
Examples of manganese compounds include organic acid salts such as manganese acetate and manganese benzoate, chlorides such as manganese chloride, alkoxides such as manganese methoxide, and manganese acetylacetonate.

Examples of the zinc compound include organic acid salts such as zinc acetate and zinc benzoate, chlorides such as zinc chloride, alkoxides such as zinc methoxide, and zinc acetylacetonate.
In the case of transesterification, the magnesium compound, calcium compound, cobalt compound, manganese compound and zinc compound are preferably added before the transesterification reaction. In the case of the esterification reaction, the addition timing of these metal compounds is not particularly limited. These compounds are used as ethylene glycol solutions.

  Examples of the germanium compound that is used as a supplementary catalyst include amorphous germanium dioxide, crystalline germanium dioxide, germanium chloride, germanium tetraethoxide, germanium tetra-n-butoxide, germanium phosphite, and the like. The amount used is about 3 to 20 ppm as the germanium content in the thermoplastic polyester.

  Examples of titanium compounds that are used as auxiliary catalysts include tetraalkyl titanates such as tetraethyl titanate, tetraisopropyl titanate, tetra-n-propyl titanate, tetra-n-butyl titanate and the like. And their partial hydrolysates, titanium acetate, titanyl oxalate, titanyl ammonium oxalate, sodium titanyl oxalate, potassium titanyl oxalate, titanyl calcium oxalate, titanyl succinate, titanium trimellitate, titanium sulfate, titanium chloride, Titanium halide hydrolyzate, titanium oxalate, titanium fluoride, potassium hexafluorotitanate, ammonium hexafluorotitanate, cobalt hexafluorotitanate, manganese hexafluorotitanate, titanium acetylacetonate, etc. Can be mentioned. The amount used is about 0.1 to 3 ppm as the titanium content in the thermoplastic polyester.

  Specific examples of the aluminum compound used as a supplementary catalyst include aluminum formate, aluminum acetate, basic aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum laurate, aluminum stearate, and benzoic acid. Carboxylates such as aluminum acid, aluminum trichloroacetate, aluminum lactate, aluminum citrate, aluminum salicylate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, polyaluminum chloride, aluminum nitrate, aluminum sulfate, aluminum carbonate, aluminum phosphate , Inorganic acid salts such as aluminum phosphonate, aluminum methoxide, aluminum ethoxide, aluminum n-propoxide, aluminum Aluminum chelates such as aluminum iso-propoxide, aluminum n-butoxide, aluminum t-butoxide, aluminum acetylacetonate, aluminum acetyl acetate, aluminum ethyl acetoacetate, aluminum ethyl acetoacetate di iso-propoxide, trimethylaluminum , Organoaluminum compounds such as triethylaluminum, and partial hydrolysates thereof, and aluminum oxide. Of these, carboxylates, inorganic acid salts and chelate compounds are preferred, and among these, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, polyaluminum chloride and aluminum acetylacetonate are particularly preferred. The amount used is about 2 to 30 ppm as the aluminum content in the thermoplastic polyester.

  Further, various phosphorus compounds can be used as the stabilizer, but pentavalent phosphorus compounds are particularly optimal. Specific examples include phosphoric acid, phosphoric acid trimethyl ester, phosphoric acid triethyl ester, phosphoric acid tributyl ester, phosphoric acid triphenyl ester, phosphoric acid monomethyl ester, phosphoric acid dimethyl ester, phosphoric acid monobutyl ester, phosphoric acid dibutyl ester, etc. Yes, these may be used alone or in combination of two or more. The amount used is 1 to 100 ppm, preferably 3 to 50 ppm, more preferably 3 to 30 ppm as the phosphorus content in the thermoplastic polyester.

  The molar ratio (Me / P) of Me to the phosphorus content (hereinafter sometimes abbreviated as P) is 0.1 to 2.0, preferably 0.2 to 1.9, more preferably 0. The range is from 3 to 1.8. When Me / P is less than 0.1, the transparency of the obtained polyester molded article from the thermoplastic polyester, particularly a thick molded article, may be very poor. On the other hand, when it exceeds 2, the thermal stability of the thermoplastic polyester is poor, and the content of aldehydes such as acetaldehyde is increased, which may cause a problem in flavor. These phosphorus compounds are used as ethylene glycol solutions.

  In addition, in order to suppress the viscosity reduction at the time of melting of the polyester composition of the present invention, or to suppress the low molecular weight by-product generated by thermal decomposition of acetaldehyde or allylaldehyde having a strong irritating odor during drying and heat treatment before molding It is also preferable to add a hindered phenolic antioxidant. As such a hindered phenolic antioxidant, a known one may be used. For example, pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate ] 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert -Butyl-4-hydroxybenzyl) benzene, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl} -2 , 4,8,10-tetraoxaspiro [5,5] undecane, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylben ) Isophthalic acid, triethylglycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,3- (3 5-di-tert-butyl-4-hydroxyphenyl) bropionate], 2,2-thio-diethylene-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3 -(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], lithium [ethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate], potassium [3,5-di-tert -Butyl-4-hydroxybenzylphosphonate ethyl], magnesium bis [3,5-di-tert-butyl-4 Ethyl hydroxybenzylphosphonate], magnesium bis [3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid], calcium bis [3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid ethyl], Calcium bis [3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid], beryllium bis [3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid methyl], strontium bis [3,5- Ethyl di-tert-butyl-4-hydroxybenzylphosphonate], ethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate 3,5-di-tert-butyl-4-hydroxyben Methyl diphosphonate, dimethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, isopropyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, 3,5-di-tert-butyl- Examples include diisopropyl 4-hydroxybenzylphosphonate, phenyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, and diphenyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate. In this case, the hindered phenol-based oxidation stabilizer may be bonded to the thermoplastic polyester, and the amount of the hindered phenol-based oxidation stabilizer in the polyester composition is 1 weight relative to the weight of the polyester composition. % Or less is preferable. This is because if it exceeds 1% by weight, it may be colored, and the ability to improve the melt stability is saturated even if it is added in an amount of 1% by weight or more. Preferably, it is 0.02 to 0.5 weight%.

  The melt polycondensation polyester obtained as described above is a method of extruding into the cooling water from the pores after completion of the melt polycondensation and cutting in water, or immediately after being extruded in the air, immediately after the cooling water having the same water quality as described above. It is preferable to form a chip in a columnar shape, a spherical shape, a square shape, or a plate shape by a method of cutting while cooling.

The sodium content (Na), the magnesium content (Mg), the silicon content (Si), and the calcium content (Ca) satisfy at least one of the following (3) to (6): It is also possible to use cooling water, and it is preferable to use water that satisfies all of (3) to (6).
Na ≦ 1.0 (ppm) (3)
Mg ≦ 1.0 (ppm) (4)
Si ≦ 2.0 (ppm) (5)
Ca ≦ 1.0 (ppm) (6)

  Next, it is preferable that the melt polycondensed polyester chip is pre-crystallized in a continuous crystallization apparatus having two or more stages in an inert gas atmosphere. For example, in the case of PET, the temperature of 100 to 180 ° C. is 1 minute to 5 hours in the first stage precrystallization, and then the temperature of 160 to 210 ° C. is 1 minute to 3 hours in the second stage precrystallization. In the pre-crystallization of the second and higher stages, it is preferable to perform crystallization step by step at a temperature of 180 to 210 ° C. for 1 minute to 3 hours. The crystallinity of the chip after crystallization is preferably in the range of 30 to 65%, preferably 35 to 63%, and more preferably 40 to 60%. The crystallinity can be obtained from the density of the chip.

Next, solid phase polymerization is carried out in an inert gas atmosphere or under reduced pressure at an optimum temperature for the prepolymer so that the increase in intrinsic viscosity due to solid phase polymerization is 0.10 deciliter / gram or more. For example, in the case of PET, the upper limit of the solid phase polymerization temperature is preferably 215 ° C. or lower, more preferably 210 ° C. or lower, particularly 208 ° C. or lower, and the lower limit is 190 ° C. or higher, preferably 195 ° C. or higher. is there.
It is preferable to set the chip temperature to about 70 ° C. or less, preferably 60 ° C. or less, more preferably 50 ° C. or less within about 30 minutes, preferably within 20 minutes, more preferably within 10 minutes after completion of the solid phase polymerization.

  The solution haze of the thermoplastic polyester used in the present invention is preferably 5.0% or less, more preferably 3.0% or less, still more preferably 2.0% or less, and most preferably 1.5% or less. Is preferred. In particular, in a polyester composition used in a large carbonated beverage container, the transparency of the thermoplastic polyester used is very important, and the solution haze is desirably 3.0% or less. When the solution haze exceeds 10.0%, only a polyester molded article with severe darkness can be obtained even with a thermoplastic polyester alone, and a polyester composition in which a partially aromatic polyamide is blended with the polyester molded article and a blackened polyester molded article obtained therefrom. Is a problem because it becomes so intense that it loses its commercial value.

The reduced antimony metal present in the thermoplastic polyester is insoluble in the solvent for measuring solution haze, and the solution haze increases as the amount of reduced antimony metal increases. Therefore, the solution haze of the thermoplastic polyester is a measure of the content of the antimony metal deposited by reduction of the antimony compound used as the polycondensation catalyst during the production of the thermoplastic polyester. In addition, solution haze is the value calculated | required by the method of the following measuring method (6).
Such a thermoplastic polyester having a solution haze of 10.0% or less can be obtained, for example, by a polycondensation reaction using an antimony compound, a second metal compound, and a phosphorus compound in the above range, and then obtained by the above production method. Yes, but not limited to these.

  The intrinsic viscosity of the thermoplastic polyester used in the present invention, particularly the thermoplastic polyester whose main repeating unit is composed of ethylene terephthalate, is preferably 0.55 to 1.50 deciliter / gram, more preferably 0.00. It is in the range of 58 to 1.30 deciliter / gram, more preferably 0.60 to 0.90 deciliter / gram. When the intrinsic viscosity is less than 0.55 deciliter / gram, the mechanical properties of the obtained molded article are poor. On the other hand, if it exceeds 1.50 deciliters / gram, the resin temperature becomes high when melted by a molding machine or the like, resulting in severe thermal decomposition, increasing the amount of free low molecular weight compounds that affect the fragrance retention, Problems such as yellowing occur.

  The intrinsic viscosity of the thermoplastic polyester used in the present invention, in particular, the thermoplastic polyester whose main repeating unit is composed of ethylene-2,6-naphthalate is 0.40 to 1.00 deciliter / gram, preferably The range is 0.42 to 0.95 deciliter / gram, more preferably 0.45 to 0.90 deciliter / gram. When the intrinsic viscosity is less than 0.40 deciliter / gram, the mechanical properties of the obtained molded article and the like are poor. On the other hand, if it exceeds 1.00 deciliter / gram, the resin temperature becomes high when melted by a molding machine or the like, resulting in severe thermal decomposition, increasing the amount of free low molecular weight compounds that affect the fragrance retention, Problems such as yellowing occur.

The intrinsic viscosity of the thermoplastic polyester according to the present invention, particularly the thermoplastic polyester whose main structural unit is composed of 1,3-propylene terephthalate, is 0.50 to 2.00 deciliter / gram, preferably 0.8. It is in the range of 55 to 1.50 deciliter / gram, more preferably 0.60 to 1.00 deciliter / gram. When the intrinsic viscosity is less than 0.50 deciliter / gram, the mechanical properties of the obtained molded article and the like are deteriorated, which is a problem. The upper limit of the intrinsic viscosity is 2.00 deciliters / gram, and if it exceeds this, the resin temperature becomes high at the time of melting by a molding machine or the like, resulting in severe thermal decomposition, drastically lowering the molecular weight, Problems such as yellow coloring occur.
The thermoplastic polyester used in the present invention is a polyester composition comprising at least two thermoplastic polyesters having a difference in intrinsic viscosity of substantially the same composition in the range of 0.05 to 0.30 deciliter / gram. There may be.

  The content of dialkylene glycol copolymerized in the thermoplastic polyester according to the present invention is preferably 0.5 to 5.0 mol%, more preferably 1 of the glycol component constituting the thermoplastic polyester. It is 0.0-4.0 mol%, More preferably, it is 1.5-3.0 mol%. When the amount of dialkylene glycol exceeds 5.0 mol%, the thermal stability is deteriorated, the decrease in molecular weight during molding is increased, and the increase in the content of aldehydes is increased. In order to produce a thermoplastic polyester having a dialkylene glycol content of less than 0.5 mol%, it is necessary to select uneconomic production conditions as transesterification conditions, esterification conditions or polymerization conditions. , Cost does not fit. Here, the dialkylene glycol copolymerized in the thermoplastic polyester, for example, in the case of a polyester whose main structural unit is ethylene terephthalate, is a diethylene glycol produced as a by-product during production from ethylene glycol, which is glycol. Among them, diethylene glycol (hereinafter abbreviated as DEG) copolymerized with the thermoplastic polyester, and in the case of a polyester having 1,3-propylene terephthalate as a main structural unit, Di (1,3-propylene glycol) (or bis (3-hydroxypropyl) ether) by-produced from 1,3-propylene glycol, which is a glycol, as a by-product during the production, is a copolymer copolymerized with the thermoplastic polyester. (1,3-propylene glycol (hereinafter referred to as DPG)). .

  The content of aldehydes such as acetaldehyde in the thermoplastic polyester according to the present invention is 50 ppm or less, preferably 30 ppm or less, more preferably 10 ppm or less. In particular, when the polyester composition of the present invention is used as a material for containers for low flavor beverages such as mineral water, the content of aldehydes in the thermoplastic polyester is 8 ppm or less, preferably 5 ppm or less, more preferably. Is desirably 4 ppm or less. When the aldehyde content exceeds 50 ppm, the effect of flavor retention of contents such as a molded article molded from this thermoplastic polyester is deteriorated. Further, these lower limits are preferably 0.1 ppb from the viewpoint of production. Here, the aldehydes are acetaldehyde when the thermoplastic polyester is a polyester having ethylene terephthalate as the main constituent unit, and in the case of polyester having 1,3-propylene terephthalate as the main constituent unit. Allyl aldehyde.

Further, the content of the cyclic ester oligomer of the thermoplastic polyester according to the present invention is 70% or less, preferably 60% or less, more preferably 70% or less of the content of the cyclic ester oligomer contained in the melt polycondensate of the thermoplastic polyester. It is preferably 50% or less, particularly preferably 35% or less.
Here, the thermoplastic polyester generally contains cyclic ester oligomers having various degrees of polymerization, but the cyclic ester oligomer referred to in the present invention is the most contained among the cyclic ester oligomers contained in the thermoplastic polyester. It means a cyclic ester oligomer having a high amount, for example, a cyclic trimer in the case of a polyester having ethylene terephthalate as a main repeating unit.

In the case of PET, which is a representative polyester whose main constituent unit is ethylene terephthalate, the thermoplastic polyester has a cyclic trimer content of the melt polycondensed polyester of about 1.0% by weight. The content of the cyclic trimer of the thermoplastic polyester according to the invention is preferably 0.70% by weight or less, preferably 0.60% by weight or less, more preferably 0.50% by weight or less.
Such a polyester having a reduced content of cyclic ester oligomer can be obtained by a method such as solid-phase polymerization of a melt polycondensed polyester or a heat treatment under an inert gas at a temperature below the melting point.
When the content of the cyclic ester oligomer exceeds 0.70% by weight, the cyclic ester oligomer increases when the resin in the injection molding is melted, and during the continuous molding, the oligomer clogging in the vent portion of the injection mold becomes severe and normal injection molding is performed. Is impossible. In addition, the adhesion of the oligomer to the surface of the heated mold after stretch blow molding becomes severe, the transparency of the obtained hollow molded body is very deteriorated, and in the case of a film, During stretching, oligomers adhere and accumulate near the die outlet, on the surface of the stretching roll, and inside the heat-fixing chamber, and these adhere to the film surface and become foreign matters. Further, these lower limits are preferably 0.2% by weight from the viewpoint of manufacturing problems and production costs.
Further, the thermoplastic polyester may be subjected to contact treatment with water, water vapor or water vapor-containing gas.

  The shape of the thermoplastic polyester chip used in the present invention may be any of a cylinder shape, a square shape, a spherical shape or a flat plate shape. The average particle size is usually 1.3 to 5 mm, preferably 1.5 to 4.5 mm, and more preferably 1.6 to 4.0 mm. For example, in the case of a cylinder type, it is practical that the length is about 1.3 to 4 mm and the diameter is about 1.3 to 4 mm. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size and the minimum particle size is 0.7 times or more the average particle size. The weight of the chip is practically in the range of 5 to 30 mg / piece.

(Partial aromatic polyamide)
The partially aromatic polyamide according to the present invention is mainly composed of a polyamide having a unit derived from an aliphatic dicarboxylic acid and an aromatic diamine as a main structural unit, or a unit derived from an aromatic dicarboxylic acid and an aliphatic diamine. Polyamide as a unit.

Examples of the aromatic dicarboxylic acid component constituting the partially aromatic polyamide according to the present invention include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, and diphenoxy. Examples include ethanedicarboxylic acid and functional derivatives thereof.
As the aliphatic dicarboxylic acid component constituting the partially aromatic polyamide according to the present invention, a linear aliphatic dicarboxylic acid is preferable, and a linear aliphatic dicarboxylic acid having an alkylene group having 4 to 12 carbon atoms is particularly preferable. preferable. Examples of such linear aliphatic dicarboxylic acids include adipic acid, sebacic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, undecanoic acid, undecadioic acid, dodecanedioic acid, dimer Examples thereof include acids and functional derivatives thereof.

Examples of the aromatic diamine component constituting the partially aromatic polyamide according to the present invention include metaxylylenediamine, paraxylylenediamine, and para-bis- (2-aminoethyl) benzene.
The aliphatic diamine component constituting the partially aromatic polyamide according to the present invention is an aliphatic diamine having 2 to 12 carbon atoms or a functional derivative thereof. The aliphatic diamine may be a linear aliphatic diamine or a branched chain aliphatic diamine. Specific examples of such linear aliphatic diamines include ethylenediamine, 1-methylethylenediamine, 1,3-propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, Examples include aliphatic diamines such as nonamethylenediamine, decamethylenediamine, undecamethylenediamine, and dodecamethylenediamine.

Moreover, as a dicarboxylic acid component which comprises the partially aromatic polyamide which concerns on this invention, alicyclic dicarboxylic acid can also be used other than the above aromatic dicarboxylic acid and aliphatic dicarboxylic acid. Examples of the alicyclic dicarboxylic acid include alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid.
Moreover, an alicyclic diamine other than the above aromatic diamine and aliphatic diamine can also be used as a diamine component constituting the partially aromatic polyamide according to the present invention. Examples of the alicyclic diamine include alicyclic diamines such as cyclohexanediamine and bis- (4,4′-aminohexyl) methane.
In addition to the diamine and dicarboxylic acid, lactams such as ε-caprolactam and laurolactam, aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid, aromatic aminocarboxylic acids such as para-aminomethylbenzoic acid, etc. It can be used as a copolymerization component. In particular, the use of ε-caprolactam is desirable.
Preferred examples of the partially aromatic polyamide according to the present invention are derived from metaxylylenediamine or mixed xylylenediamine containing metaxylylenediamine and 30% or less of the total amount of paraxylylenediamine and an aliphatic dicarboxylic acid. A metaxylylene group-containing polyamide containing at least 20 mol% or more, more preferably 30 mol% or more, particularly preferably 40 mol% or more in the molecular chain.
Further, the partially aromatic polyamide according to the present invention contains structural units derived from a polybasic carboxylic acid having 3 or more bases such as trimellitic acid and pyromellitic acid within a substantially linear range. Also good.

  Examples of these polyamides include homopolymers such as polymetaxylylene adipamide, polymetaxylylene sebacamide, polymetaxylylene speramide, and metaxylylenediamine / adipic acid / isophthalic acid copolymers, metaxylylene. / Paraxylylene adipamide copolymer, metaxylylene / paraxylylene piperamide copolymer, metaxylylene / paraxylylene azelamide copolymer, metaxylylenediamine / adipic acid / isophthalic acid / ε-caprolactam copolymer And metaxylylenediamine / adipic acid / isophthalic acid / ω-aminocaproic acid copolymer.

In addition, other preferable examples of the partially aromatic polyamide according to the present invention include at least 20 mol of a structural unit derived from an aliphatic diamine and at least one acid selected from terephthalic acid or isophthalic acid in the molecular chain. % Or more, more preferably 30 mol% or more, particularly preferably 40 mol% or more.
Examples of these polyamides include polyhexamethylene terephthalamide, polyhexamethylene isophthalamide, hexamethylene diamine / terephthalic acid / isophthalic acid copolymer, polynonamethylene terephthalamide, polynonamethylene isophthalamide, nonamethylene diamine / terephthalic acid. / Isophthalic acid copolymer, nonamethylenediamine / terephthalic acid / adipic acid copolymer, and the like.

  Other preferable examples of the partially aromatic polyamide according to the present invention include, in addition to at least one acid selected from aliphatic diamine and terephthalic acid or isophthalic acid, lactams such as ε-caprolactam and laurolactam, and aminocapron. Selected from aliphatic diamine and terephthalic acid or isophthalic acid obtained by using aminocarboxylic acid such as acid, aminoundecanoic acid, aromatic aminocarboxylic acid such as para-aminomethylbenzoic acid as copolymerization component A polyamide containing at least 20 mol% or more, more preferably 30 mol% or more, particularly preferably 40 mol% or more of a structural unit derived from at least one acid in the molecular chain.

  Examples of these polyamides include hexamethylenediamine / terephthalic acid / ε-caprolactam copolymer, hexamethylenediamine / isophthalic acid / ε-caprolactam copolymer, hexamethylenediamine / terephthalic acid / adipic acid / ε-caprolactam copolymer Examples include coalescence.

  The polyamide according to the present invention basically comprises a conventionally known melt polycondensation method in the presence of water or a melt polycondensation method in the absence of water, or a polyamide obtained by these melt polycondensation methods. It can be produced by a method of phase polymerization. The melt polycondensation reaction may be performed in one stage or may be performed in multiple stages. These may be composed of batch reactors or may be composed of continuous reactors. Further, the melt polycondensation step and the solid phase polymerization step may be operated continuously or may be operated separately.

It is preferable to add a phosphorus compound or an alkali metal compound to the partially aromatic polyamide according to the present invention in order to prevent coloration or improve thermal stability.
Phosphorus compound and alkali metal compound content (P) and alkali metal atom content (M), which are added as stabilizers during the production of the polyamide (the amount of alkali metal atoms contained in the phosphorus compound and the alkali metal) The total amount with the amount of alkali metal atoms contained in the compound preferably satisfies the ranges of the following formulas (7) and (8).
30 ≦ P ≦ 400 ppm (7)
1 <M / P molar ratio <7 (8)

  Regarding P, the lower limit is more preferably 35 ppm, and still more preferably 50 ppm or more. The upper limit is preferably 370 ppm, more preferably 350 ppm or less. The lower limit for the M / P molar ratio is more preferably 1.3, and even more preferably 1.5 or more. When the phosphorus atom content is less than 30 ppm, the color tone of the polymer is deteriorated and the thermal stability is inferior. Conversely, if the phosphorus atom content is more than 400 ppm, the raw material cost for the additive will increase, which will contribute to the cost increase, and the filter will be clogged with foreign substances at the time of melt molding. There is concern about a decline in productivity. On the other hand, if the M / P molar ratio is 1 or less, there is a risk that the viscosity will increase sharply and the gelled product will be mixed in a lot. On the other hand, when the M / P molar ratio is 7 or more, the reaction rate is very slow and the productivity cannot be denied.

  Moreover, the phosphorus atom content (P1) derived from the phosphorus compound detected in the structure of the structural formula (formula 1) in the partially aromatic polyamide according to the present invention is 1 ppm or more, more preferably 5 ppm or more, and still more preferably. It is preferable that it is 10 ppm or more. When P1 is less than 1 ppm, not only the thermal stability of the polyester composition of the present invention is deteriorated, but the resulting polyester molded product is not only easily colored but also easily gelled, and the obtained hollow molded product or film is obtained. There are cases where foreign matters and fish eyes are generated more and more in molded articles such as, and the flavor retention is also deteriorated, thereby reducing the commercial value. The upper limit is 300 ppm or less, preferably 200 ppm or less, more preferably 150 ppm or less. Since the phosphorus compound is oxidized during the polycondensation step, it is difficult to produce a polyamide with P1 exceeding 300 ppm.

  As a phosphorus compound used at the time of the polyamide manufacture which concerns on this invention, the compound represented by following Chemical formula (A-1)-(A-4) is mentioned, The compound represented by (A-1) is preferable.

(In the chemical formulas (A-1) to (A-4), R _{1 to} R ₇ are hydrogen, alkyl group, aryl group, cycloalkyl group or arylalkyl group, X _{1 to} X ₅ are hydrogen, alkyl group, An aryl group, a cycloalkyl group, an arylalkyl group, an alkali metal, or an alkaline earth metal, or one of each of X _{1 to} X ₅ and R _{1 to} R ₇ in each formula is linked to each other to form a ring structure (May do)

  Examples of the phosphinic acid compound represented by the chemical formula (A-1) include dimethylphosphinic acid, phenylmethylphosphinic acid, hypophosphorous acid, sodium hypophosphite, potassium hypophosphite, lithium hypophosphite, hypochlorous acid. Magnesium phosphate, calcium hypophosphite, ethyl hypophosphite,

Or

And hydrolysates thereof, and condensates of the above phosphinic acid compounds.

  Examples of the phosphonic acid compound represented by the chemical formula (A-2) include phosphonic acid, sodium phosphonate, potassium phosphonate, lithium phosphonate, potassium phosphonate, magnesium phosphonate, calcium phosphonate, phenylphosphonic acid, ethylphosphonic acid, Examples include sodium phenylphosphonate, potassium phenylphosphonate, lithium phenylphosphonate, diethyl phenylphosphonate, sodium ethylphosphonate, and potassium ethylphosphonate.

  Examples of the phosphonous acid compound represented by the chemical formula (A-3) include phosphonous acid, sodium phosphonite, lithium phosphonite, potassium phosphonite, magnesium phosphonite, calcium phosphonite, and phenylphosphonous acid. , Sodium phenylphosphonite, potassium phenylphosphonite, lithium phenylphosphonite, ethyl phenylphosphonite, and the like.

  As the phosphite compound represented by the chemical formula (A-4), phosphorous acid, sodium hydrogen phosphite, sodium phosphite, lithium phosphite, potassium phosphite, magnesium phosphite, calcium phosphite, Examples include triethyl phosphite, triphenyl phosphite, pyrophosphorous acid and the like.

Moreover, in the production of the polyamide according to the present invention, it is preferable to add an alkali metal-containing compound represented by the following chemical formula (B). The alkali metal atom content in the partially aromatic polyamide is preferably in the range of 1 to 1000 ppm.
Z-OR ₈ (B)
(However, Z is an alkali metal, _{R 8} is hydrogen, an alkyl group, an aryl group, a cycloalkyl group, -C (O) CH ₃ or -C (O) OZ ', ( Z' is hydrogen, an alkali metal))

  Examples of the alkali compound represented by the chemical formula (B) include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, lithium acetate, sodium acetate, potassium acetate, rubidium acetate, cesium acetate, sodium methoxy And sodium ethoxide, sodium propoxide, sodium butoxide, potassium methoxide, lithium methoxide, sodium carbonate, etc., among which sodium hydroxide and sodium acetate are preferably used. However, any of them is not limited to these compounds.

In order to mix the phosphorus compound or the alkali metal-containing compound with the polyamide according to the present invention, the raw materials before the polymerization of the polyamide, these may be added during the polymerization, or may be melt mixed into the polymer.
These compounds may be added simultaneously or separately.

Hereinafter, a preferred batch production method of a polyamide according to the present invention will be described using a xylylene group-containing polyamide (Ny-MXD6) as an example, but the present invention is not limited thereto.
That is, for example, a salt of metaxylylenediamine and adipic acid, an alkali metal-containing compound containing an alkali metal atom as a thermal decomposition inhibitor, and an aqueous solution of a phosphorus compound are heated under pressure and normal pressure to produce water and a polycondensation reaction. It can be obtained by a method of polycondensation in a molten state while removing water generated in step (b).
At this time, it is preferable that the tank for storing metaxylylenediamine and the tank for storing adipic acid have a nitrogen gas atmosphere separately, and the oxygen concentration in the nitrogen gas atmosphere is 50 ppm or less. More preferably, it is 30 ppm, and most preferably 20 ppm. When the oxygen content in the nitrogen gas atmosphere in the storage tank exceeds 50 ppm, the phosphorus atom content (P1) derived from the phosphorus compound represented by the structural formula (formula 1) in the obtained polyamide is less than 1 ppm. The heat stability of polyamide will be poor. Moreover, as a method of suppressing the oxygen concentration in the atmosphere in the storage tank, an inert gas such as nitrogen is allowed to flow into the tank, the air is replaced with nitrogen gas, and then an inert gas such as nitrogen gas is allowed to flow. Is preferable. Moreover, as a method of reducing the oxygen content in each raw material, it is preferable to bubble an inert gas from the bottom of the can. As the inert gas used, it is preferred to use nitrogen gas having an oxygen content of 20 ppm or less, more preferably 1 ppm or less.

Also, in the step of mixing the raw materials, various additives and water, and adjusting the salt of metaxylylenediamine and adipic acid, the oxygen concentration in the nitrogen gas atmosphere is 50 ppm or less, more preferably 30 ppm or less, more It is preferably 25 ppm or less, and most preferably 20 ppm or less. Further, as a method for lowering the oxygen concentration, a method of bubbling using an inert gas, for example, nitrogen gas, in the salt aqueous solution can be mentioned. Also in this step, when the oxygen content exceeds 50 ppm, the phosphorus atom content (P1) derived from the phosphorus compound represented by the structural formula (formula 1) in the obtained polyamide becomes less than 1 ppm, and the heat stability of the polyamide It will be inferior.
The temperature at which the salt is prepared is preferably 140 ° C. or lower, more preferably 130 ° C. or lower in order to suppress coloring due to thermal oxidative degradation or to suppress side reactions or thermal oxidative degradation reactions of additives. More preferably, it is 120 ° C. or less, and most preferably 110 ° C. or less. The lower limit is preferably a temperature at which the salt does not solidify, and is 30 ° C. or higher, more preferably 40 ° C. or higher.

  Next, the prepared aqueous salt solution is transferred to a polymerization vessel and subjected to polycondensation. To evaporate water in the aqueous salt solution, in order to prevent scattering of unreacted substances and to prevent oxygen from being mixed into the system, While applying a pressure of 0.5 to 1.5 MPa in the can, the temperature was gradually raised, the distilled water was removed from the system, and the temperature in the can was 230 ° C. The reaction time at this time is preferably 1 to 10 hours, more preferably 2 to 8 hours, and further preferably 3 to 7 hours. An abrupt temperature rise is not preferable because it causes a high molecular weight of the additive and a side reaction of the polymer and causes a decrease in the thermal stability of the resin such as gelation in a subsequent process. Thereafter, the internal pressure of the can was gradually released over 30 to 90 minutes and returned to normal pressure. Further, the temperature was raised and the mixture was stirred at normal pressure to proceed the polymerization reaction. The polymerization temperature is preferably 285 ° C. or less, more preferably 275 ° C. or less, further preferably 270 ° C. or less, and most preferably 265 ° C. or less. When the polymerization temperature is higher than 285 ° C., it is not preferable because the additive has a high molecular weight and the thermal oxidation reaction or side reaction of the polymer further proceeds. The lower limit is preferably a temperature that does not solidify based on the polymer melting point. The polymerization time is preferably as short as possible, but is preferably within 3 hours, more preferably within 2 hours, and even more preferably within 1.5 hours.

  When the target viscosity was reached, stirring was stopped and allowed to stand to remove bubbles in the polymer. It is not preferable to leave it for a long time because it causes heat deterioration. The molten resin was taken out from the outlet at the bottom of the reaction can, cooled and solidified, and a resin chip was obtained with a chip cutter such as a strand cutter. In this case, if the time required for casting is long, it is not preferable because it is greatly affected by thermal oxidation deterioration at the take-out port, or the resin in the can etc. is thermally deteriorated and gelled products are formed or colored. . On the other hand, if the casting is too short, the temperature of the strand-shaped polymer coming out from the outlet becomes too high, so that the resin and additives are susceptible to thermal oxidative degradation, which may contribute to a decrease in the thermal stability of the polymer. Therefore, in the case of a batch reactor, the casting time is preferably 10 to 120 minutes, more preferably 15 to 100 minutes. Moreover, the strand polymer temperature in that case becomes like this. Preferably it is 20-70 degreeC, More preferably, it is the range of 30-65 degreeC. As another method, as a method for preventing thermal oxidative degradation of the polymer at the outlet, a method of spraying an inert gas can be mentioned.

The relative viscosity of the polyamide according to the present invention is 1.5 to 4.0, preferably 1.5 to 3.0, more preferably 1.7 to 2.5, and still more preferably 1.8 to 2.0. It is a range. When the relative viscosity is 1.5 or less, the molecular weight is too small, and the molded article such as a polyamide film according to the present invention may be inferior in mechanical properties. On the other hand, if the relative viscosity is 4.0 or more, it takes a long time for the polymerization, which may cause deterioration of the polymer, gelation or undesired coloring, as well as decrease in productivity and increase in cost. Sometimes.
In addition, the shape of the polyamide chip according to the present invention may be any of a cylinder shape, a square shape, a spherical shape, a flat plate shape, and the like. The average particle size is usually in the range of 1.0 to 5 mm, preferably 1.2 to 4.5 mm, more preferably 1.5 to 4.0 mm. For example, in the case of a cylinder type, it is practical that the length is about 1.0 to 4 mm and the diameter is about 1.0 to 4 mm. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size and the minimum particle size is 0.7 times or more the average particle size. The weight of the chip is practically in the range of 3-50 mg / piece.

(Polyester composition)
The polyester composition of the present invention is a polyester composition comprising 99.9 to 70% by weight of the thermoplastic polyester and 0.1 to 30% by weight of the partially aromatic polyamide.
In the case where it is desired to obtain a molded article having a very low content of aldehydes and excellent flavor retention from the polyester composition, the amount of the partially aromatic polyamide added is 99.9 to 95% by weight of the thermoplastic polyester. On the other hand, it is 0.1 to 5% by weight. The lower limit of the amount of the partially aromatic polyamide added is more preferably 0.2% by weight, even more preferably 0.3% by weight, most preferably 0.5% by weight, and the upper limit is more preferably 4% by weight. Preferably it is 3 weight%.

  Addition of partially aromatic polyamide when it is desired to obtain a molded article with excellent gas barrier properties, transparency that does not impair practicality, and very low aldehyde content and excellent flavor retention The amount is 1 to 30% by weight of partially aromatic polyamide with respect to 99 to 70% by weight of the thermoplastic polyester. The lower limit of the amount of the partially aromatic polyamide added is more preferably 3% by weight, still more preferably 5% by weight, and the upper limit is more preferably 25% by weight, still more preferably 20% by weight.

  When the amount of the partially aromatic polyamide is less than 0.1% by weight, the content of aldehydes such as AA in the obtained molded product is difficult to be reduced, and the flavor retention of the molded product content is very poor. There is a case. Further, when the amount of the partially aromatic polyamide added exceeds 30% by weight, the transparency of the obtained molded product tends to be very poor, and the mechanical properties of the molded product may be deteriorated.

  The product of the phosphorus atom content (P1) derived from the phosphorus compound detected by the structural formula (formula 1) in the partially aromatic polyamide and the content (A) of the partially aromatic polyamide in the polyester composition ( The upper limit value of P1 × A) is preferably 450 or less, more preferably 400 or less. Moreover, the lower limit of the formula (1) is preferably 1 or more, more preferably 5 or more. By using the polyester composition satisfying the formula (1), a reduction in antimony atoms in the polyester composition hardly occurs, and a polyester molded article excellent in transparency without darkening can be obtained.

  In addition, the phosphorus atom content (P1) derived from the phosphorus compound detected by the structural formula (formula 1) in the partially aromatic polyamide and the phosphorus atom derived from the phosphorus compound detected by the structural formula (formula 2) The upper limit of the product [(P1 + P2) × A] of the sum of the amount (P2) and the content (A) of the partially aromatic polyamide in the polyester composition is preferably 800 or less, more preferably 700. It is as follows. Moreover, the lower limit value of the formula (2) is preferably 1 or more, more preferably 10 or more. By using a polyester composition satisfying the formula (2), a polyester molded body having excellent transparency without darkening can be obtained.

  That is, the phosphorus compound added to the partially aromatic polyamide changes to compounds having phosphorus structures in various oxidation states during polycondensation. There are two structural formulas of phosphorus for reducing the antimony atom in the thermoplastic polyester, the structural formula (formula 1) and the structural formula (formula 2), and in order to prevent darkening, these in the polyester composition Therefore, it is important to regulate the content of the amount to the range of the formula (1) or the formula (2).

  The haze of the polyester molded product obtained by molding the polyester composition of the present invention is 25% or less, preferably 20% or less. In particular, in a polyester composition used for a beverage container, the haze is desirably 15% or less. In addition, haze is the value calculated | required about the 2 mm-thick molded board obtained by the method of the following measuring method (12).

  Moreover, the acetaldehyde content of the polyester molding obtained by shape | molding the polyester composition of this invention is 25 ppm or less, Preferably it is 20 ppm or less. In particular, in a polyester composition used for a beverage container, the acetaldehyde content is 15 ppm or less, preferably 10 ppm or less, more preferably 8 ppm or less. In addition, acetaldehyde content is the value calculated | required about the 2 mm-thick molded board obtained by the method of the following measuring method (12).

  The polyester composition of the present invention can be produced by adding a predetermined amount of partially aromatic polyamide in any reaction stage from the production of the low-polymerization oligomer of the thermoplastic polyester to the production of the melt polycondensation polymer. it can. For example, the partially aromatic polyamide is added to a reactor such as an esterification reactor or a polycondensation reactor in an appropriate form such as a fine granule, a powder, or a melt. The partially aromatic polyamide or a mixture of the partially aromatic polyamide and the polyester is introduced in a molten state into a transport pipe for the reaction product of the polyester. Furthermore, it is also possible to obtain a chip obtained by solid phase polymerization under a high vacuum or an inert gas atmosphere if necessary.

  The polyester composition of the present invention can also be obtained by mixing the thermoplastic polyester and the partially aromatic polyamide by a conventionally known method. For example, the polyamide chip and the polyester chip are dry blended with a tumbler, V-type blender, Henschel mixer, etc., and the dry blended mixture is melted at least once with a single screw extruder, twin screw extruder, kneader, etc. Examples thereof include a mixture, and a chip obtained by subjecting a chip from a molten mixture to solid phase polymerization under a high vacuum or an inert gas atmosphere if necessary.

  Further, the polyamide may be crushed and used. The particle size when pulverized is preferably about 10 mesh or less. Also, a method in which a solution obtained by dissolving the polyamide in a solvent such as hexafluoroisopropanol is attached to the surface of a thermoplastic polyester chip, and the thermoplastic polyester collides with the member in a space where the polyamide member exists. The method of making it contact and making the said polyamide adhere to the surface of the said thermoplastic polyester chip is mentioned.

  In the polyester composition of the present invention, other additives such as known ultraviolet absorbers, antioxidants, oxygen absorbers, oxygen scavengers, lubricants added from the outside, and internal precipitation during the reaction are carried out as necessary. Various additives such as lubricants, mold release agents, nucleating agents, stabilizers, antistatic agents, and pigments may be blended. Moreover, it is also possible to mix the ultraviolet blocking resin, the heat resistant resin, the recovered product from the used polyethylene terephthalate bottle, and the like at an appropriate ratio.

In addition, when the polyester composition of the present invention is used for a film, the polyester composition contains calcium carbonate, magnesium carbonate, barium carbonate in order to improve handling properties such as slipperiness, rollability, and blocking resistance. , Inorganic particles such as calcium sulfate, barium sulfate, lithium phosphate, calcium phosphate, magnesium phosphate, organic salt particles such as terephthalate such as calcium oxalate, calcium, barium, zinc, manganese, magnesium, divinylbenzene, styrene, acrylic Inactive particles such as crosslinked polymer particles such as acid, methacrylic acid, acrylic acid or a vinyl monomer of methacrylic acid, or a copolymer thereof can be contained.
The polyester composition of the present invention may be formed into a film, a sheet-like product, a container, other molded products, fibers containing monofilaments, etc. by using a commonly used melt molding method, or may be separated by a melt extrusion method. A coated coating can be formed on the substrate.

In addition, as described above, the polyester composition of the present invention is melted so that a predetermined amount of partially aromatic polyamide is added to any reactor or transport pipe in the production process of the melt polycondensation polymer, and the desired characteristics are obtained. After polycondensation, it is introduced directly into the molding process in the molten state to form a molded body, or a predetermined amount of partially aromatic polyamide is added and mixed in the transport pipe installed after the final melt polycondensation reactor, and the molten state It can also be directly introduced into the molding process to form a molded body.
The sheet-like material comprising the polyester composition of the present invention can be produced by a means known per se. For example, it can be manufactured using a general sheet forming machine equipped with an extruder and a die.
Further, this sheet-like material can be formed into a cup shape or a tray shape by pressure forming or vacuum forming. Moreover, the polyester molding from the polyester composition of this invention can be used also for the use of the tray-shaped container for cooking food with a microwave oven and / or an oven range, or heating frozen food. . In this case, after the sheet-like material is formed into a tray shape, it is thermally crystallized to improve heat resistance.
When the polyester composition of the present invention is a stretched film, a sheet obtained by injection molding or extrusion molding is usually uniaxially stretched, sequentially biaxially stretched, and simultaneously biaxially stretched for PET. Of these, it shape | molds using arbitrary extending | stretching methods.

Below, the concrete manufacturing method about the various uses in the case of PET is demonstrated easily.
In producing a stretched film, the stretching temperature is usually 80 to 130 ° C. Stretching may be uniaxial or biaxial, but biaxial stretching is preferred from the viewpoint of film physical properties. In the case of uniaxial stretching, the stretching ratio is usually 1.1 to 10 times, preferably 1.5 to 8 times. In the case of biaxial stretching, the longitudinal and transverse directions are usually 1.1 to 8 times, respectively. Preferably, it may be performed in a range of 1.5 to 5 times. The vertical / horizontal magnification is usually 0.5 to 2, preferably 0.7 to 1.3. The obtained stretched film can be further heat-set to improve heat resistance and mechanical strength. The heat setting is usually performed under tension at 120 to 240 ° C., preferably 150 to 230 ° C., usually for several seconds to several hours, preferably several tens of seconds to several minutes.

  In producing a hollow molded body, a preform molded from PET is stretch blow molded, and an apparatus conventionally used in blow molding of PET can be used. Specifically, for example, once a preform is formed by injection molding or extrusion molding, the plug part and the bottom part are processed as it is, and then reheated, and then biaxial stretch blow molding such as hot parison method or cold parison method The law applies. The molding temperature in this case, specifically, the temperature of each part of the cylinder of the molding machine and the nozzle is usually in the range of 260 to 290 ° C. The stretching temperature is usually 70 to 120 ° C., preferably 90 to 110 ° C., and the stretching ratio is usually 1.5 to 3.5 times in the longitudinal direction and 2 to 5 times in the circumferential direction. The obtained hollow molded body can be used as it is, but in particular in the case of beverages that require hot filling, such as fruit juice beverages and oolong teas, it is generally heat-set in a blow mold and heat resistant. Used to impart sex. The heat setting is usually performed at 100 to 200 ° C., preferably 120 to 180 ° C. for several seconds to several hours, preferably several seconds to several minutes, under tension by compressed air or the like.

In order to impart heat resistance to the plug part, the plug part of the preform obtained by injection molding or extrusion molding is crystallized in a far infrared or near infrared heater installation oven, Alternatively, the mouthpiece is crystallized with the above heater after molding the bottle.
The polyester composition of the present invention can also be used for the production of a stretched hollow molded body by a so-called compression molding method in which a preform obtained by compression molding a melt mass cut after melt extrusion is stretch blow molded. Can do.

  Moreover, the polyester composition of this invention can be used also as one component layer which took the form of the film form or the coating-film form in composite molded objects, such as a laminated molded object and a laminated film. In particular, it is used for manufacturing containers and the like in the form of a laminate with PET. Examples of laminated molded products include a two-layer structure composed of two layers of an outer layer made of the polyester composition of the present invention and an inner layer of PET, or composed of two layers of an inner layer made of the polyester composition of the present invention and an outer layer of PET. A molded article having a two-layer structure, a three-layer structure composed of an intermediate layer containing the polyester composition of the present invention and an outer layer and an innermost layer of PET, or an intermediate layer between the outer layer and innermost layer containing the polyester composition of the present invention and PET Examples include a three-layered molded body composed of layers, a five-layered molded body composed of an intermediate layer containing the polyester composition of the present invention, an innermost layer of PET, a central layer, and an innermost layer. In the PET layer, other gas barrier resins, ultraviolet blocking resins, heat resistant resins, recovered products from used polyethylene terephthalate bottles, and the like can be mixed and used at an appropriate ratio.

Other examples of the laminated molded body include a laminated molded body with a resin other than polyester such as polyolefin, and a laminated molded body with a different type of substrate such as paper or a metal plate.
There is no restriction | limiting in particular in the thickness of the said laminated molded object, and the thickness of each layer. The laminated molded body can be used in various shapes such as a sheet-like material, a film-like material, a plate-like material, a hollow body, and a container.
The production of the laminate can be carried out by coextrusion using a number of extruders corresponding to the type of the resin layer and a multi-layered multi-die, and the number of injection machines corresponding to the type of the resin layer It can also be done by co-injection using a co-injection runner and injection mold.

Another application of the polyester composition of the present invention is a film that is laminated on one or both sides of a laminated metal plate. Examples of the metal plate used include tinplate, tin-free steel, and aluminum.
As a laminating method, a conventionally known method can be applied, and it is not particularly limited, but it is preferable to carry out by a thermal laminating method that can achieve organic solvent-free and can avoid adverse effects on the taste and odor of food products due to the residual solvent. In particular, the thermal laminating method by energization processing of a metal plate is particularly recommended. In the case of double-sided lamination, lamination may be performed simultaneously or sequentially.
Needless to say, a film can be laminated to a metal plate using an adhesive.
Moreover, a metal container is obtained by shape | molding using the said laminated metal plate. The method for forming the metal container is not particularly limited. Further, the shape of the metal container is not particularly limited, but is preferably applied to a so-called two-piece can produced by a molding process such as drawing, drawing and ironing, and stretch draw molding. The present invention can also be applied to a so-called three-piece can in which a top cover suitable for filling a food product such as a coffee drink is wrapped to fill the contents.
The main characteristic value measuring methods in the present invention will be described below.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. The main characteristic value measuring methods in this specification will be described below.

(Evaluation methods)
(1) Intrinsic viscosity of polyester (IV)
It calculated | required from the solution viscosity at 30 degreeC in a 1,1,2,2-tetrachloroethane / phenol (2: 3 weight ratio) mixed solvent.

(2) Diethylene glycol content copolymerized in polyester (hereinafter referred to as “DEG content”)
The product was decomposed with methanol, the amount of diethylene glycol was quantified by gas chromatography, and expressed as a ratio (mol%) to the total glycol components.

(3) Content of cyclic trimer (hereinafter referred to as “CT content”)
300 mg of the frozen and ground sample is dissolved in 3 ml of a hexafluoroisopropanol / chloroform mixed solution (volume ratio = 2/3), and further diluted with 30 ml of chloroform. To this is added 15 ml of methanol to precipitate the polymer, followed by filtration. The filtrate was evaporated to dryness, adjusted to a constant volume with 10 ml of dimethylformamide, and the cyclic trimer was quantified by high performance liquid chromatography.

(4) Acetaldehyde content (hereinafter referred to as “AA content”)
Sample / distilled water = 1 g / 2 cc of glass ampoule substituted with nitrogen was sealed and subjected to extraction treatment at 160 ° C for 2 hours. After cooling, acetaldehyde in the extract was measured by high-sensitivity gas chromatography. The concentration was expressed in ppm.
For the polyester composition, a plate having a thickness of 2 mm is collected from the stepped molded body obtained in (12), and for the hollow molded body, a sample is collected from the center of the bottom thereof.

(5) Residual catalyst content in polyester After 2.0 g of PET was incinerated by a conventional method in the presence of sulfuric acid, the ash was dissolved in 100 ml of distilled water. The metal element in this solution was quantified by ICP emission spectroscopy.

(6) Polyester solution haze After 5 g of polyester was dissolved in 50 cc of the mixed solvent of (1), the solution was placed in a 20 mm thick cell and measured with a Nippon Denshoku Co., Ltd. haze meter, model NDH2000.

(7) Co-L, Co-b of polyester chip, Co-b of polyamide chip
Co-L and Co-b values were measured using a color meter (manufactured by Nippon Denshoku Co., Ltd., Model 1001DP).

(8) Relative viscosity of polyamide (hereinafter referred to as “Rv”)
0.25 g of a sample was dissolved in 25 ml of 96% sulfuric acid, and 10 ml of this solution was measured at 20 ° C. with an Ostwald viscosity tube and obtained from the following formula.
Rv = t / t ₀
t ₀ : the number of seconds the solvent falls t : Sample solution dropping seconds

(9) Structural analysis of phosphorus compound in polyamide ( ³¹ P-NMR method)
A sample of 340 to 350 mg was dissolved in 2.5 ml of a mixed solvent of heavy benzene / 1,1,1,3,3,3-hexafluoroisopropanol = 1/1 (vol ratio), and tri (t-butylphenyl) phosphate ( Hereinafter, TPPPA is abbreviated as P) and 100 ppm is added to the polyamide resin, 0.1 ml of trifluoroacetic acid is further added, and after 30 minutes, ³¹ P-NMR analysis is performed with a Fourier transform nuclear magnetic resonance apparatus (AVANCE500 manufactured by BRUKER). went. The ³¹ P resonance frequency is 202.5 MHz, the detection pulse flip angle is 45 °, the data acquisition time is 1.5 seconds, the delay time is 1.0 second, the integration number is 1000 to 20000 times, the measurement temperature is room temperature, and the proton is completely decoupled. Analysis was performed under ring conditions.

  From the obtained NMR chart, the peak integrated value of each phosphorus compound is calculated, and the moles of the phosphorus compound represented by the structural formula (formula 1) and the phosphorus compound represented by the structural formula (formula 2) from the following formula A: The ratio was determined.

    Molar ratio of phosphorus compound = XP1 / XP2 (formula A)

(XP1 is the peak integral value of the phosphorus compound represented by the structural formula (formula 1), and XP2 is the peak integral value of the phosphorus compound represented by the structural formula (formula 2).)

  Next, the P peak integrated value corresponding to TBPPA (tri (t-butylphenyl) phosphoric acid) is defined as 100 ppm, and the total of all the P peak integrated values in the polyamide observed in the region of 15 ppm to -15 ppm. The P peak integral value PN is calculated.

  Next, P peak relative values (Ps) of all phosphorus compounds observed in the NMR spectrum are obtained from the following formula B.

    P peak relative value (Ps) = PN / PC (formula B)

(PN is the total P peak integral value (ppm) of polyamide, and PC is the phosphorus atom content (ppm) in the polyamide. Here, the phosphorus atom content PC in the polyamide is determined by the analysis method of (4) below. (If the P peak relative value is greater than 1, P peak relative value = 1)

  Next, the ratio (P1r) of the phosphorus compound detected in the structure of the structural formula (formula 1) in the polyamide and the ratio (P2r) of the phosphorus compound detected in the structure of the structural formula (formula 2) are expressed by the following formula C, Calculate from D.

      P1r = Ps × (P peak integrated value XP1 of phosphorus compound detected by structure of structural formula (formula 1) in polyamide) / PN (formula C)

      P2r = Ps × (P peak integral value XP2 of phosphorus compound detected by structure of structural formula (formula 2) in polyamide) / PN (formula D)

  In addition, when the P peak relative value is smaller than 1, the total value of the proportions of the respective phosphorus compounds in the polyamide does not become 100. This is because there is a phosphorus compound that does not dissolve in the preparation of the polyamide solution by the above method. It is.

  In the polyamides used in Examples and Comparative Examples, the phosphorus compound corresponding to the structural formula (Formula 1) is hypophosphorous acid (the following (Chemical Formula 9)), and the peak due to this structure is in the range of 9 to 12 ppm. It was seen in. Further, the phosphorus compound corresponding to the structural formula (Formula 2) is phosphorous acid (the following (Chemical Formula 10)), and the peak due to this structure was found in the range of 4 to 7 ppm.

  Next, the phosphorus atom content (P1) derived from the phosphorus compound detected in the structure of the structural formula (formula 1) and the phosphorus atom content derived from the phosphorus compound detected in the structure of the structural formula (formula 2) by the following formula The quantity (P2) is determined.

Phosphorus compound-derived phosphorus atom content (P1) (ppm) detected in the structure of structural formula (Formula 1) = PC × P1r
Phosphorus compound-derived phosphorus atom content (P2) (ppm) detected by the structure of structural formula (Formula 2) = PC × P2r

  FIG. 1 shows the NMR spectrum of P.

(10) Analysis of P content (P) of polyamide The sample is subjected to dry ash decomposition in the presence of sodium carbonate, or wet decomposition in sulfuric acid / nitric acid / chlorinated acid or sulfuric acid / hydrogen peroxide water system to correct phosphorus. Phosphoric acid was used. Subsequently, the molybdate is reacted in a 1 mol / L sulfuric acid solution to form phosphomolybdic acid, and this is reduced with hydrazine sulfate. The absorbance at 830 nm of the heteropoly blue produced is a spectrophotometer (Shimadzu Corporation, UV-150- 02) and colorimetrically determined.

(11) Analysis of Na content (Na) of polyamide A sample was incinerated and decomposed with a platinum crucible, and 6 mol / L hydrochloric acid was added to evaporate to dryness. The resultant was dissolved in 1.2 mol / L hydrochloric acid, and the solution was quantified by atomic absorption (manufactured by Shimadzu Corporation, AA-640-12).

(12) Molding of stepped molding plate
A polyester or a polyester composition dried under reduced pressure at 140 ° C. for about 16 hours using a Yamato Scientific vacuum dryer DP61 type is shown in FIGS. 2 and 3 by an injection molding machine M-150C-DM type injection molding machine manufactured by Meiki Seisakusho. 2 mm to 11 mm having a gate part (G) (A part thickness = 2 mm, B part thickness = 3 mm, C part thickness = 4 mm, D part thickness = 5 mm, E part thickness = 10 mm, F A stepped molded plate having a thickness of part thickness = 11 mm) was injection molded.
In order to prevent moisture absorption during molding, the inside of the molding material hopper was purged with a dry inert gas (nitrogen gas). The plasticizing conditions of the M-150C-DM injection molding machine are as follows: feed screw rotation speed = 70%, screw rotation speed = 120 rpm, back pressure 0.5 MPa, cylinder temperature 45 ° C., 250 ° C. from the bottom of the hopper in order, nozzle The temperature was set at 290 ° C. The injection conditions are 20% for injection speed and holding pressure, and the injection pressure and holding pressure are adjusted so that the weight of the molded product is 146 ± 0.2 g. In this case, the holding pressure is 0.5 MPa relative to the injection pressure. Adjusted low.
The upper limit of the injection time and pressure holding time is set to 10 seconds and 7 seconds, respectively, and the cooling time is set to 50 seconds. The total cycle time including the time for taking out the molded product is about 75 seconds.
Although the temperature of the mold is always controlled by introducing cooling water having a water temperature of 10 ° C., the mold surface temperature at the time of stable molding is around 22 ° C.
The test plate for evaluating the molded product characteristics was arbitrarily selected from the 11th to 18th shots of the stable molded product after the molding material was introduced and the resin was replaced.
A 2 mm thick plate (part A in FIG. 2) is used for AA measurement.

(13) Molding of hollow molded body M, manufactured by Meiki Seisakusho, using a predetermined amount of PET polyester dried by a dryer using nitrogen gas and a predetermined amount of partially aromatic polyamide dried by a dryer using nitrogen gas. A preform was molded at a resin temperature of 290 ° C. using a −150 C-DM type injection molding machine. This preform was subjected to biaxial stretching blow molding using an LB-01E stretching blow molding machine manufactured by Corpoplast to obtain a 1500 cc hollow molded body.

(14) Transparency of hollow molded body 100 pieces obtained in (13) were visually observed and evaluated as follows.
◎: Transparent ○: Transparent within a practical range and no foreign matter such as unmelted material is observed △: Transparent within a practical range, but foreign material such as an unmelted material is observed ×: Transparent Inferior in nature, colored or unmelted

(15) Yellowness of preform (PF) The appearance of PF obtained after molding 100 PFs at (13) was visually observed from the length direction and evaluated as follows.
◎: Yellowing is not observed ○: Yellowing is slightly observed, but is in a practical range △: Yellowing is considerably observed ×: Coloring is severe and practicality is poor

(16) Blackening of preform (PF) The appearance of PF obtained after molding 100 PFs in (13) was visually observed from the length direction and evaluated as follows.
◎: No darkening is observed. ○: A little darkening is observed, but it is in a practical range. △: Blackening is considerably observed. ×: Darkening is severe, and practicality is poor.

(17) Oxygen permeation rate (cc / one container / 24hr / atm)
The permeation amount per 1500 cc bottle was measured at 20 ° C. and 0% RH with an oxygen permeation meter OX-TRAN100 manufactured by Modern Controls.

(Polyethylene terephthalate (PET) used in Examples and Comparative Examples)
(Polyester 1 (Pes1))
An EG slurry of TPA adjusted to a molar ratio of EG to TPA of 1.7 is continuously supplied to the system containing the reaction product in the first esterification reactor, and an average residence time of 4 hours at normal pressure. And reaction at a temperature of 255 ° C.
This reaction product was continuously taken out of the system and supplied to the second esterification reaction apparatus, and reacted at a normal pressure at an average residence time of 2.5 hours in each tank at a temperature of 260 ° C.
Subsequently, the esterification reaction product was continuously taken out from the second esterification reactor and continuously supplied to the continuous polycondensation reactor. From a plurality of polycondensation catalyst supply pipes connected to the transport pipe for the esterification reaction product, an amount of phosphorus is 0.65 mol (about 20 ppm with respect to the produced polyester resin) as phosphorus atoms per ton of the produced polyester resin. EG solution of acid, EG solution of magnesium acetate tetrahydrate in an amount such that 0.62 mol (about 15 ppm with respect to the resulting polyester resin) magnesium atoms per ton of the produced polyester resin, and 1 ton of the produced polyester resin An EG solution of antimony trioxide in an amount of 1.40 mol per antimony atom (about 170 ppm with respect to the produced polyester resin) is fed to the esterification reaction product, and is stirred at about 265 ° C. and 25 torr. 1 hour, then in a second polycondensation reactor with stirring at about 265 ° C. and 3 torr for 1 hour. Under stirring with a final polycondensation reactor, about 275 ° C., it was polycondensed at 0.5～1Torr. The intrinsic viscosity of the melt polycondensed prepolymer was 0.64 dl / g.

After the melt polycondensation reaction product has been chipped, it is sent to a crystallization apparatus and continuously crystallized at about 155 ° C. for 3 hours under a nitrogen gas flow, and then charged into a tower-type solid phase polymerization vessel. Solid phase polymerization was continuously carried out at 206 ° C. to obtain a solid phase polymerized polyester.
The obtained PET has an intrinsic viscosity of 0.85 deciliter / gram, a DEG content of 2.7 mol%, a cyclic trimer content of 0.45 wt%, an AA content of 3.5 ppm, Co-L Was 95.0, Co-b was 1.0, and the solution haze was 1.0%. The antimony content measured by atomic absorption analysis was about 170 ppm.
This PET was evaluated using a molded plate. The results are shown in Table 1.

(Polyester 2 (Pes2))
Instead of magnesium acetate, EG solution of cobalt acetate tetrahydrate in an amount of 0.34 mol (about 20 ppm with respect to the produced polyester resin) as cobalt atoms per ton of the produced polyester resin, per ton of produced polyester resin An EG solution of phosphoric acid in an amount of 0.65 mol as phosphorus atoms (about 20 ppm with respect to the produced polyester resin), and 1.56 mol as antimony atoms per ton of produced polyester resin (with respect to the produced polyester resin) Polyester 2 was obtained by reacting in the same manner as Polyester 1 except that an EG solution of antimony trioxide in an amount such that it was about 190 ppm) was used.
The properties of the obtained PET are shown in Table 1.

(Polyester 3 (Pes3))
Without using the second metal compound, the EG solution of phosphoric acid and the amount listed in Table 1 as antimony atoms per ton of the produced polyester resin so that the amount described in Table 1 as phosphorous atoms per ton of the produced polyester resin A polyester 3 was obtained by reacting in the same manner as the polyester 1 except that an EG solution of antimony trioxide was used.
The properties of the obtained PET are shown in Table 1.

(Polyester 4 (Pes4))
EG solution of phosphorous acid that does not use the second metal compound and has the amount described in Table 1 as phosphorus atoms per ton of the produced polyester resin, and listed in Table 1 as antimony atoms per ton of the produced polyester resin Polyester 4 was obtained by reacting in the same manner as Polyester 1 except that an EG solution of antimony trioxide was used in an amount of
The properties of the obtained PET are shown in Table 1.

(Partial aromatic polyamide used in Examples and Comparative Examples)
The polyamide used was obtained by a batch method in which metaxylylenediamine and adipic acid were heated under pressure and normal pressure in the presence of NaOH or NaH ₂ PO ₂ .H ₂ O in a pressure-resistant polycondensation vessel. It is a thing.
Table 2 shows the characteristics of Ny-MXD6 (A) to Ny-MXD6 (F) used in the test.
(Ny-MXD6 (A))
Precisely metered amounts of metaxylylenediamine, adipic acid and water are added to an adjustment can equipped with a stirrer, a condenser, a thermometer, a dropping funnel, and a nitrogen gas introduction tube, and pressure and release operations are performed with nitrogen gas. The nitrogen substitution was repeated 5 times, and the oxygen content in the atmospheric nitrogen was adjusted to 9 ppm or less. The internal temperature at that time was 80 ° C. Further, NaOH or NaH ₂ PO ₂ .H ₂ O was added as an additive and stirred to obtain a uniform salt aqueous solution. At this time, the oxygen content in the atmospheric nitrogen was maintained at 7 ppm or less.
This solution is transferred to a reaction can equipped with a stirrer, a partial reducer, a thermometer, a dropping funnel and a nitrogen gas introduction tube, and the temperature is gradually raised at a can internal temperature of 190 ° C. and a can internal pressure of 1.0 MPa, and distilled. Water was removed from the system, and the internal temperature was set to 230 ° C. The reaction time until this time was 5 hours. Thereafter, the internal pressure of the can was gradually released over 60 minutes, and returned to normal pressure. The temperature was further raised to 255 ° C., stirred at normal pressure for 20 minutes to reach a predetermined viscosity, and the reaction was completed. Then, it was left to stand for 20 minutes, air bubbles in the polymer were removed, the molten resin was extruded from the bottom of the reaction can, and casting was performed while cooling and solidifying with cold water. The casting time was about 70 minutes, and the temperature of the cooled and solidified resin was 50 ° C.
The total amount of sodium hypophosphite and sodium hydroxide was 1.80 times mol of phosphorus atoms. The characteristics of the obtained Ny-MXD6 are shown in Table 2.

(Ny-MXD6 (B), (C), (D))
It was obtained by the same polymerization method as Ny-MXD6 (A) except that NaOH and NaH ₂ PO ₂ .H ₂ O were added so as to achieve the contents shown in Table 2. The characteristics of the obtained Ny-MXD6 are shown in Table 2.
(Ny-MXD6 (E))
It was obtained by the same polymerization method as Ny-MXD6 (A) except that the amount ratio of metaxylylenediamine and adipic acid was changed. The characteristics of the obtained Ny-MXD6 are shown in Table 2.
(Ny-MXD6 (F))
It was obtained by the same polymerization method as Ny-MXD6 (A) except that NaOH and NaH ₂ PO ₂ .H ₂ O were added so as to achieve the contents shown in Table 2. The characteristics of the obtained Ny-MXD6 are shown in Table 2.
(Ny-MXD6 (G))
The above phosphorus atom-containing compound and alkali compound were not added and were obtained by the same polymerization method as Ny-MXD6 (A). The characteristics of the obtained Ny-MXD6 are shown in Table 2.
(Ny-MXD6 (H))
It was obtained by the same polymerization method as Ny-MXD6 (A) except that NaOH and NaH ₂ PO ₂ .H ₂ O were added so as to achieve the contents shown in Table 2. The characteristics of the obtained Ny-MXD6 are shown in Table 2.

Example 1
Evaluation was performed by the above-described evaluation method using Ny-MXD6 (C) 0.1% by weight with respect to 99.9% by weight of Pes (1). The obtained evaluation results are shown in Table 3.
P1 × A in the polyester composition was 3, and (P1 + P2) × A was 6.5, and the AA content of the molded body from this polyester composition was as low as 13 ppm, and there was no problem.
In addition, the preform obtained from this composition did not show yellowing and darkening, both were ◎, and the transparency of the bottle was ◎.

(Examples 2 to 11)
The polyester compositions described in Table 3 were evaluated in the same manner as in Example 1.
The obtained evaluation results are shown in Table 3.
All the results were fine.

(Comparative Example 1)
Evaluation was performed by the above evaluation method using 3% by weight of Ny-MXD6 (H) with respect to 97% by weight of Pes (4). The obtained evaluation results are shown in Table 3.
P1 × A in the polyester composition was 1200, and (P1 + P2) × A was 1620, and the AA content of the molded body from this polyester composition was 20 ppm, which was a problem.
The degree of darkening of the preform was x, and no unmelted product was observed in the bottle, but the transparency was a problem with x.

(Comparative Example 2)
Using the polyester composition described in Table 3, the evaluation was performed by the evaluation method described above. The obtained evaluation results are shown in Table 3.
P1 × A in the polyester composition is 750, (P1 + P2) × A is 1250, the yellowing degree of the preform is Δ (considerable yellowing), the darkening degree is x, and the bottle is unmelted Although the thing was not recognized, the transparency was a problem with x.

(Comparative Example 3)
Using the composition described in Table 3, the evaluation was performed by the above evaluation method. The obtained evaluation results are shown in Table 3.
The AA content of the molded plate from the polyester composition was as high as 19 ppm, the preform was discolored to yellow-brown, and an unmelted product was present in the bottle.

(Comparative Example 4)
Evaluation was performed using only Pes (4). The obtained evaluation results are shown in Table 3.
The preform was considerably darkened (Δ) and the AA content was as high as 28 ppm.

  As mentioned above, although the polyester composition of this invention was demonstrated based on the several Example, this invention is not limited to the structure described in the said Example, The structure described in each Example is combined suitably etc. The configuration can be changed as appropriate without departing from the spirit of the invention.

  According to the polyester composition of the present invention, there is no darkening, and a polyester molded article excellent in transparency, flavor retention and thermal stability, or transparency, flavor retention, thermal stability and gas barrier properties can be obtained. In addition, as described above, the polyester molded body of the present invention is very suitable as a molded body for beverages such as soft drinks.

³¹ P-NMR spectrum of a typical example Plan view of the stepped molded plate used in the examples Side view of the stepped molded plate of FIG.

Explanation of symbols

A Part A part of stepped molded plate B Part B part of stepped molded plate C Part C of stepped molded plate
D Part D of stepped molded plate
E Part E of stepped molded plate
F Part of stepped molded plate F part G Gate part of stepped molded plate

Claims (9)

A polyester composition comprising 99.9 to 70% by weight of a thermoplastic polyester containing an antimony compound and 0.1 to 30% by weight of a partially aromatic polyamide, wherein the phosphorus atom content (P1 in the partially aromatic polyamide) ) And the content (A) of the partially aromatic polyamide in the polyester composition satisfy the following formula (1).
(However, P1 is a phosphorus compound-derived phosphorus detected in the structure of the following structural formula (formula 1) when the partial aromatic polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added followed by structural analysis. Atomic content.)

(Wherein R ₁ and R ₂ are hydrogen, alkyl group, aryl group, cycloalkyl group or arylalkyl group, and X ₁ is hydrogen)
0 <(P1 × A) ≦ 500 (1)
In formula (1),
P1: Content of phosphorus atom derived from phosphorus compound detected by the above structural formula (formula 1) in partially aromatic polyamide (ppm)
A: Content (% by weight) of partially aromatic polyamide in the polyester composition A polyester composition comprising 99.9 to 70% by weight of a thermoplastic polyester containing an antimony compound and 0.1 to 30% by weight of a partially aromatic polyamide, wherein the phosphorus atom content (P1) and the partially aromatic A polyester composition characterized in that the phosphorus atom content (P2) in the polyamide and the content (A) of the partially aromatic polyamide in the polyester composition satisfy the following formula (2).
(However, P2 is a phosphorus compound-derived phosphorus detected by the structure of the following structural formula (formula 2) when the partial aromatic polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added and then the structure is analyzed. Atomic content.)

(Wherein R ₃ is hydrogen, an alkyl group, an aryl group, a cycloalkyl group or an arylalkyl group, X ₂ and X ₃ are hydrogen)
0 <(P1 + P2) × A ≦ 900 (2)
In formula (2),
P1: Content of phosphorus atom derived from phosphorus compound detected by the above structural formula (formula 1) in partially aromatic polyamide (ppm)
P2: phosphorus atom content (ppm) derived from the phosphorus compound detected by the above structural formula (formula 2) in the partially aromatic polyamide
A: Content (% by weight) of partially aromatic polyamide in the polyester composition The polyester composition according to claim 1, wherein the solution haze of the thermoplastic polyester is 10.0% or less. The polyester composition according to any one of claims 1 to 3, wherein the content of antimony atoms remaining in the thermoplastic polyester is 100 to 400 ppm. The polyester composition according to any one of claims 1 to 4, wherein the content of all residual phosphorus atoms in the partially aromatic polyamide is 70 to 400 ppm. The polyester composition according to any one of claims 1 to 5, wherein an acetaldehyde content of a molded product obtained by injection molding is 15 ppm or less. A polyester molded article obtained by molding the polyester composition according to claim 1. The polyester molded body according to claim 7, wherein the polyester molded body is any one of a hollow molded body, a sheet-like material, and a stretched film obtained by stretching the sheet-like material in at least one direction. A polyester molded article according to claim 7, wherein the polyester molded article is a coating melt-extruded on a substrate.

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