JP2003113295A - Polyester resin composition and molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester resin composition comprising g a polyester resin and a polyamide resin, used for a film, a sheet, a thin-walled hollow vessel or the like excellent in gas barrier properties, transparency, color tone and pinhole resistance. SOLUTION: This resin composition is obtained by melt-kneading a diol having cyclic acetal skeleton and a polyethylene terephthalate resin to a component including the polyester resin and the polyamide resin or/and the polyethylene terephthalate resin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyester resin and a polyamide resin obtained by polycondensation using a diol component containing a dicarboxylic acid or diol having a cyclic acetal skeleton, or a component obtained by further adding a polyethylene terephthalate resin. The present invention relates to a polyester resin composition excellent in transparency, gas barrier property and pinhole resistance and a molded product thereof.

[0002]

2. Description of the Related Art Polyester resins (hereinafter sometimes referred to as "aromatic polyester resins") containing an aromatic dicarboxylic acid as a representative dicarboxylic acid component and an aliphatic diol as a main diol component represented by polyethylene terephthalate resin are Performance, melt stability, solvent resistance,
It has the characteristics of excellent aroma retention and recyclability, and is widely used for packaging materials such as films, sheets and hollow containers. However, since the gas barrier properties of oxygen, carbon dioxide gas, etc. are not always good, there is a limitation in use in applications requiring high gas barrier properties. As means for imparting gas barrier properties to the aromatic polyester resin, there are means such as laminating a metal foil such as aluminum, coating or laminating another resin having a high gas barrier property, and vapor depositing aluminum or silicon. However, there are problems that transparency is impaired, complicated manufacturing processes are required, and mechanical performance is impaired.

Therefore, as a means for imparting a high gas barrier property without requiring a complicated manufacturing process, there is a method of mixing another resin having a high gas barrier property. Nylon 6 and Nylon 66 as resins with high gas barrier properties
Polyamide resins represented by, for example, etc., but particularly a polyamide resin obtained by polycondensing metaxylylenediamine and adipic acid (hereinafter sometimes referred to as “polyamide MXD6”) has excellent gas barrier properties. On the other hand, there is an ethylene-polyvinyl alcohol copolymer resin as a gas barrier resin other than the polyamide resin, but the ethylene-vinyl alcohol copolymer resin has a poor compatibility with the aromatic polyester resin, so that both compositions are cloudy, Since the crystallinity is high, there are problems such as impairing the stretchability of the aromatic polyester resin and poor thermal stability.

On the other hand, polyamide MXD6 has a high gas barrier property, is close in glass transition temperature, melting point and crystallinity to aromatic polyester resin, especially polyethylene terephthalate, and is also excellent in thermal stability during melting. . Therefore, the melt mixing with the aromatic polyester resin is easy. There are advantages that a high gas barrier property is exhibited without impairing the mechanical performance and stretchability of the aromatic polyester resin.

However, since a resin composition comprising an aromatic polyester resin and a polyamide resin such as polyamide MXD6 is not sufficiently transparent, its use is limited in applications requiring high transparency.

Therefore, a method in which an anhydride is added to tetracarboxylic acid to a mixture of a polyamide resin and a polyester resin (JP-A-1-272660), a thermoplastic polyester resin and a polyamide resin having a metaxylylene group in its main chain are used. A method of using a compound having an epoxy group and an acid anhydride group as one of the compatibilizers for the composition (Japanese Patent Publication No.
No. 2871), a method in which a polycarboxylic acid compound is blended with an aromatic polyester and melt-kneaded (JP-A-2000).
No. 302952), however, any method requires a complicated manufacturing process. Further, a method using polyethylene terephthalate (PET) and polymethaxylylene adipamide having a relative viscosity ratio within a certain specific range (JP 2001-2800A) has been proposed, but sufficient transparency is obtained. In addition, there is a sanitary problem of the compatibilizer when used for food packaging, etc., and the contents in the packaging look different from the actual contents because it causes yellowing and pearlescence. There are also problems.

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above problems, and is a film made of a polyester resin and a polyamide resin, which is excellent in gas barrier properties, transparency, color tone, and pinhole resistance, It is intended to provide a polyester resin composition which can be used for a sheet, a thin hollow container and the like.

[0008]

Means for Solving the Problems As a result of intensive investigations by the present inventors, polyester resin and polyamide resin as raw material monomers, or a component obtained by further adding polyethylene terephthalate resin to a diol or polyethylene terephthalate resin having a cyclic acetal skeleton. It has been found that the resin composition for a film, sheet and thin hollow container having excellent gas barrier properties, transparency, color tone and pinhole resistance can be obtained by melt-kneading, and the present invention has been completed.

That is, the present invention provides a polyester resin composition (D) comprising a polyamide resin (A) and a polyester resin (B), or a polyamide resin (A), a polyester resin (B) and a polyethylene terephthalate resin (C). ), Wherein the polyester resin (B) contains 0.5 to 60 dicarboxylic acid having a cyclic acetal skeleton.
A polyester resin obtained by polycondensation using a diol component containing 0.5 to 60 mol% of a dicarboxylic acid component containing mol% and / or a diol having a cyclic acetal skeleton, and a mixing ratio of each component is polyamide. Polyamide resin (A) is 1 to 99% by weight, polyester resin (B) is 1 to 99% by weight, and polyethylene terephthalate is based on the total weight of resin (A), polyester resin (B) and polyethylene terephthalate resin (C). A polyester resin composition and a molded product thereof, wherein the resin (C) is in the range of 0 to 98% by weight.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition of the present invention is a polyester resin composition comprising a polyamide resin (A) and a specific polyester resin (B), or further a polyethylene terephthalate resin (C). The resin, the compounding ratio thereof, the mixing method, and the molded product made of the polyester resin composition used in the present invention will be specifically described.

Polyamide Resin (A) The polyamide resin (A) used in the present invention is a known moldable resin obtained by polymerizing amino acids, lactams or diamines and dicarboxylic acids as monomers. Specific examples of the amino acid monomer include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, para-aminomethylbenzoic acid and the like, and examples of the lactam include ε-caprolactam and ω-laurolactam. .

As the diamine monomer, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-
Trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, meta-xylylenediamine, para-xylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis ( Aminomethyl) cyclohexane, 1
-Amino-3-aminomethylhexane, 5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis Examples thereof include diamines such as (aminopropyl) piperazine and aminoethylpiperazine, but are not limited thereto.

Examples of the dicarboxylic acid monomer include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, cyclohexanedicarboxylic acid, decalindicarboxylic acid, norbornanedicarboxylic acid, tricyclodecane. Dicarboxylic acid, pentacyclododecane dicarboxylic acid, isophorone dicarboxylic acid, 3,9-bis (2-carboxyethyl) 2,4,8,10-tetraoxaspiro [5.5]
Undecane, trimellitic acid, trimesic acid, pyromellitic acid, tricarballylic acid, terephthalic acid, isophthalic acid, phthalic acid, 2-methylterephthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid, tetralindicarboxylic acid and their esterified products Can be illustrated,
It is not limited to these.

Specific examples of polyamide resins obtained from these monomers include polymethaxylylene adipamide (polyamide MXD6), polycaproamide (nylon 6),
Polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), polyundecamethylene adipamide (nylon 116), polyhexamethylene dodecamide (nylon 612), polyundecane amide (nylon 11) ), Polydodecanamide (nylon 12) and copolymerized amides thereof. These polyamide resins can be used alone or in admixture of two or more. Among these, as the polyamide resin used in the present invention, nylon MXD6 is used.
Is particularly preferable.

Polyamide MXD6 has a high gas barrier property, is close in glass transition temperature, melting point and crystallinity to aromatic polyester resin, especially polyethylene terephthalate, and is also excellent in thermal stability during melting. for that reason,
It is easy to melt-mix with the aromatic polyester resin. There are advantages that a high gas barrier property is exhibited without impairing the mechanical performance and stretchability of the aromatic polyester resin. Further, the diamine component of the polyamide MXD6 preferably contains metaxylenediamine in an amount of 70 mol% or more, and preferably contains adipic acid in the dicarboxylic acid component in an amount of 70 mol% or more. When the polyamide MXD6 is in the above blending range, excellent gas barrier properties and mechanical performance can be maintained.

The relative viscosity of the polyamide resin (A) used in the present invention (value measured by dissolving 1 g of polyamide resin in 100 ml of 96% sulfuric acid and measuring at 25 ° C.) is 1.83 to 4.2.
0, preferably 2.02 to 4.20, more preferably 2.30 to 4.20. By setting the relative viscosity of the polyamide to be 1.83 or more, die swell and melting unevenness caused by instability of the fluidity of the molten resin at the time of molding a film, sheet, hollow container or the like made of the polyester resin composition of the present invention. Can be effectively prevented. Furthermore, the relative viscosity of the polyamide resin (A) is 1.8.
When it is 3 or more, the moldability of a film, sheet, hollow container or the like made of the polyester resin composition of the present invention is improved, the effect of transparency of the molded product is recognized, and whitening is performed in a high humidity atmosphere. It is possible to suppress a decrease in transparency due to.

The polyamide resin (A) used in the present invention preferably has a water content of 0.15% or less, preferably 0.1% or less. The polyamide can be dried by a conventionally known method. For example, a method of removing water in the polymer by depressurizing the vent hole when melt-extruding the polyamide with an extruder with a vent, charging the polyamide resin into a tumbler (rotary vacuum tank),
Examples thereof include a method of heating at a temperature equal to or lower than the melting point of the polymer under reduced pressure and drying, but the method is not limited thereto.

Polyester Resin (B) The diol component or dicarboxylic acid component having a cyclic acetal skeleton, which is a raw material of the polyester resin (B) of the present invention, is 0.5 mol% or more in each component, preferably 1
It is at least mol%, more preferably at least 2 mol%. By setting such a diol or dicarboxylic acid in the above range, the polyester-based resin composition of the present invention has excellent mechanical strength, transparency, color tone and pinhole resistance, such as films, sheets, and thin hollow containers. A molded body can be provided. Further, the diol component or dicarboxylic acid component having a cyclic acetal skeleton, which is a raw material of the polyester resin (B) of the present invention, accounts for 60 mol% in each component.
Or less, preferably 45 mol% or less, more preferably 30
It is at most mol%, particularly preferably at most 20 mol%. By setting the diol or dicarboxylic acid in the above range,
The polyester resin composition of the present invention is excellent in moldability, transparency and economy.

The aliphatic diol having a cyclic acetal skeleton which is a raw material of the polyester resin (B) is preferably a compound represented by the general formula (1) or (2).

[Chemical 5]

[Chemical 6] (In the general formulas (1) and (2), R and R ′ each have 1 carbon atom.
10 represents an organic group selected from the group consisting of an aliphatic group, an alicyclic group and an aromatic group. )

Specific examples of the compound represented by the general formula (1) or (2) include 3,9-bis (1,1-dimethyl-2).
-Hydroxyethyl) 2,4,8,10-tetraoxaspiro [5.5] undecane, 5-methylol-5-ethyl-2- (1,1-dimethyl-2-hydroxyethyl) -1,3-dioxane Can be exemplified. By using the aliphatic diol having such a cyclic acetal skeleton, from the polyester resin composition of the present invention,
It is possible to obtain a molded product such as a film, a sheet, and a thin hollow container having excellent mechanical strength, transparency, color tone and pinhole resistance.

The dicarboxylic acid component having a cyclic acetal skeleton is preferably a compound represented by the general formula (3) or (4).

[Chemical 7]

[Chemical 8] (In the general formulas (3) and (4), R, R ′, and R ″ represent an organic group selected from the group consisting of an aliphatic group having 1 to 10 carbon atoms, an alicyclic group, and an aromatic group, and R '''Is H, methyl group,
An ethyl group or an isopropyl group is shown. )

Specific examples of the compound represented by formula (3) or (4) include 3,9-bis (2-carboxyethyl) 2,4,8,10-tetraoxaspiro [5.5].
Undecane, 5-methylol-5-ethyl-2- (1,
Examples include 1-dimethyl-2-carboxyethyl) -1,3-dioxane. By using a dicarboxylic acid component having such a cyclic acetal skeleton, from the polyester resin composition of the present invention, mechanical strength, transparency, a film excellent in color tone and pinhole resistance, such as a sheet and a thin hollow container A molded product can be obtained.

As the diol other than the diol having a cyclic acetal skeleton, which is the raw material of the polyester resin (B) used in the present invention, ethylene glycol, 1,
3-propylene diol, 1,4-butane diol,
Examples include 1,4-cyclohexanedimethanol and 1,6-hexanediol. When obtaining the polyester resin composition of the present invention, ethylene glycol is preferably used
The above effect becomes more remarkable when a diol monomer component containing 0 to 99.5 mol%, more preferably 40 to 99 mol%, and particularly preferably 50 to 99 mol% is used.

The polyester resin (B) used in the present invention contains a large amount of monoalcohols such as butyl alcohol, hexyl alcohol and octyl alcohol and trimethylolpropane, glycerin, pentaerythritol and the like within a range not impairing the object of the present invention. Polyhydric alcohols can also be used as the diol component of the raw material monomer.

The dicarboxylic acid component of the polyester resin (B) used in the present invention is preferably an aromatic dicarboxylic acid component, for example, terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, biphenyl dicarboxylic acid, etc. and their esters. An example is a forming derivative. In particular, the use of terephthalic acid and its ester-forming derivatives is desirable. The polyester resin (B) used in the present invention includes, as a dicarboxylic acid component, an aliphatic dicarboxylic acid such as adipic acid and sebacic acid, and a monocarboxylic acid such as benzoic acid, propionic acid and butyric acid as long as the purpose is not impaired. Can be used. The proportion of the aromatic dicarboxylic acid in the dicarboxylic acid component is preferably 70 mol% or more, more preferably 80% or more, particularly preferably 9%.
It is 0 mol% or more. By setting the above mixing ratio,
The polyester resin composition of the present invention has more excellent heat resistance and mechanical performance.

The polyester resin (B) used in the present invention is, in addition to the aromatic dicarboxylic acid component, a polyvalent carboxylic acid compound in which three or more carboxyl groups in one molecule are bonded to an aromatic ring, or a polycarboxylic acid compound bonded to the compound. A polyvalent carboxylic acid compound in which two or more of the carboxyl groups forming an anhydrous ring may be contained. For example, trimellitic acid, pyromellitic acid, trimellitic acid anhydride, various naphthalene tricarboxylic acid anhydrides having different bonding positions of the carboxyl group to the aromatic ring, various anthracentricarboxylic acids, various benzophenone tricarboxylic acid anhydrides, benzenetetracarboxylic acid Anhydrides, various naphthalene tetracarboxylic dianhydrides, various anthracene tetracarboxylic dianhydrides, various biphenyl tetracarboxylic dianhydrides,
Examples thereof include ethylene bis trimellitic anhydride.

The method for producing the polyester resin (B) of the present invention is not particularly limited, and conventionally known methods can be applied. For example, a melt polymerization method such as a transesterification method and a direct esterification method, or a solution polymerization method can be mentioned. The transesterification catalyst, the esterification catalyst, the etherification inhibitor, the polymerization catalyst used for the polymerization, the various stabilizers such as the heat stabilizer and the light stabilizer, and the polymerization regulator may be those conventionally known. As a transesterification catalyst, manganese,
Examples thereof include compounds such as cobalt, zinc, titanium and calcium, compounds such as manganese, cobalt, zinc, titanium and calcium as esterification catalysts and amine compounds as etherification inhibitors.

Examples of the polycondensation catalyst include compounds such as germanium, antimony, tin and titanium. It is also effective to add various phosphorus compounds such as phosphoric acid, phosphorous acid and phenylphosphonic acid as heat stabilizers. In addition, a light stabilizer, an antistatic agent, a lubricant, an antioxidant, a release agent, etc. may be added.

Polyester resin (B) used in the present invention
Is preferably dried to a water content of 300 ppm or less, preferably 100 ppm or less. The intrinsic viscosity of the polyester resin used in the present invention (phenol /
The mass ratio of 1,1,2,2-tetrachloroethane is 60 /
The value measured at 25 ° C. in a mixed solvent of 40)
Although not particularly limited, it is usually 0.3 to 2.0 dl / g, preferably 0.4 to 1.8 dl / g.
When the intrinsic viscosity is 0.3 or more, the molecular weight of the polyester resin is sufficiently high, so that a molded product made of the polyester resin composition obtained by using the polyester resin has particularly excellent mechanical performance.

When the polyester resin (B) used in the present invention is measured at a measuring temperature of 255 ° C. and a shear rate of 100 s ⁻¹ , the melt viscosity is preferably in the range of 500 to 5000 Pa · s, more preferably 500 to 2000 Pa.・ S range. When the melt viscosity is in the above range, the moldability of a film, sheet, thin hollow container and the like is particularly excellent.

The polyester resin (B) used in the present invention preferably has a molecular weight distribution of 2.3 to 12.0.
More preferably, it is 2.5 to 8.0. When the molecular weight distribution is in the above range, the moldability of a film, a sheet, a thin hollow container and the like is particularly excellent. Here, the molecular weight distribution is
Weight average molecular weight (Mw) relative to number average molecular weight (Mn)
Is the ratio (Mw / Mn). The molecular weight distribution is 2.3-1
It can be adjusted to 2.0 by selecting the amount of the dicarboxylic acid or diol having a cyclic acetal skeleton and the addition timing thereof, the molecular weight of the polyester, the polymerization temperature, and the additive.

Polyethylene terephthalate resin (C) The polyethylene terephthalate resin (C) optionally used in the present invention is a polyester containing terephthalic acid as a main acid component and ethylene glycol as a main glycol. Here, the "main" is 85 mol%
The amount exceeds. Therefore, ester units other than terephthalic acid and ethylene glycol can be contained within the range of less than 15 mol%, and such copolymerization components include terephthalic acid, dicarboxylic acids other than ethylene glycol, and diols or oxyacids. In addition to the aromatic dicarboxylic acid component, a polyvalent carboxylic acid compound in which three or more carboxyl groups are bonded to an aromatic ring in one molecule or two or more of the carboxyl groups bonded to the compound are anhydrous. A polyvalent carboxylic acid compound forming a ring may be contained.

Specifically, as diol components other than ethylene glycol, trimethylene glycol, 1,4-
Butanediol, 1,5-pentanediol, 1,6-
Hexanediol, diethylene glycol, propylene glycol, neopentyl glycol and other aliphatic diols, polyethylene glycol, polypropylene glycol, polybutylene glycol and other polyether compounds, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,2-decahydronaphthalene dimethanol, 1,3-decahydronaphthalene dimethanol, 1,4-decahydronaphthalene dimethanol, 1,5-decahydronaphthalene dimethanol, 1,
Alicyclic diols such as 6-decahydronaphthalenedimethanol, 2,7-decahydronaphthalenedimethanol, tetralindimethanol, norbornanedimethanol, tricyclodecanedimethanol, pentacyclododecandimethanol, 4,4′- Alkylene oxide adducts of bisphenols such as (1-methylethylidene) bisphenol, methylenebisphenol (bisphenol F), 4,4′-cyclohexylidenebisphenol (bisphenol Z), and 4,4′-sulfonylbisphenol (bisphenol S), Hydroquinone, resorcin,
Examples thereof include alkylene oxide adducts of aromatic dihydroxy compounds such as 4,4′-dihydroxybiphenyl, 4,4′-dihydroxydiphenyl ether, and 4,4′-dihydroxydiphenylbenzophenone.

As the dicarboxylic acid component other than the aromatic dicarboxylic acid component, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, cyclohexanedicarboxylic acid, decalin dicarboxylic acid, Examples thereof include norbornane dicarboxylic acid, tricyclodecane dicarboxylic acid, pentacyclododecane dicarboxylic acid and isophorone dicarboxylic acid.

As the polyvalent carboxylic acid compound, trimellitic acid, pyromellitic acid, trimellitic anhydride, various naphthalene tricarboxylic acid anhydrides having different bonding positions of the carboxyl group to the aromatic ring, various anthracentrycarboxylic acids, various benzophenone tricarboxylic acids Anhydride, benzenetetracarboxylic monoanhydride, various naphthalenetetracarboxylic dianhydride, various anthracene tetracarboxylic dianhydride, various biphenyltetracarboxylic dianhydride,
Examples thereof include ethylene bis trimellitic anhydride.

Blending Ratio The blending ratio in the polyester resin composition (D) of the present invention is such that the polyamide resin (A) is 1 to 99% by weight, the polyester resin (B) is 1 to 99% by weight, and the polyethylene terephthalate resin ( C) is 0 to 98% by weight. When the polyester resin composition (D) comprises the polyamide resin (A) and the polyester resin (B), the polyamide resin (A) is preferably 5 to 95% by weight, and more preferably 1
It is 0 to 90% by weight, the polyester resin (B) is preferably 95 to 5% by weight, and more preferably 90 to 10% by weight. By setting the mixing ratio of the polyamide resin and the polyester resin within this range, it is possible to obtain a resin composition having respective advantages.

When the polyester resin composition (D) comprises the polyamide resin (A), the polyester resin (B) and the polyethylene terephthalate resin (C), the mixing ratio of the polyamide resin (A) is preferably 1 to 50% by weight. , And more preferably 5 to 45% by weight. When the polyamide resin (A) is 1% by weight or more, a high gas barrier property can be obtained. When the polyester resin composition (D) is composed of the polyamide resin (A), the polyester resin (B) and the polyethylene terephthalate resin (C), the polyamide resin (A) is 79% by weight.
The polyester resin composition having excellent transparency and economy can be obtained by the following.

Further, the polyester resin (B) in this case
The compounding ratio of is 79% by weight or less, preferably 45% by weight
It is the following. When the content is 79% by weight or less, the transparency is maintained and heat setting is possible during the production of the stretched film. Further, the blending ratio of the polyethylene terephthalate resin (C) in this case is 20% by weight or more, preferably 50% by weight or more. When the content is 20% by weight or more, high mechanical performance can be obtained and the economy is excellent.
The polyethylene terephthalate resin (C) in the resin composition is 98% by weight or less, preferably 90% by weight or less. When the content is 98% by weight or less, high transparency and gas barrier property can be obtained.

Mixing Method The resins used in the method for producing the polyester resin composition (D) of the present invention can be mixed by a conventionally known method. For example, a polyamide resin (A) and a polyester resin (B), or a polyethylene terephthalate resin (C) are dry-blended with a tumbler, a V-type blender, a Hayschel mixer, or the like, and the dry-blended mixture is a uniaxial extruder. , A twin-screw extruder, a kneader or the like that has been melt-mixed at least once, and further, a melt-mixed product that has been subjected to solid-state polymerization under high vacuum or an inert gas atmosphere, if necessary.

The polyester resin composition (D) of the present invention may be obtained by melt-kneading a mixture of a polyamide resin (A) and a polyester resin (B), or a polyethylene terephthalate resin (C) which is dry-blended.
The pre-kneaded product obtained by melt-kneading the polyamide resin (A) and the polyester resin (B) and the dry-blended mixture of the polyethylene terephthalate (C) may be melt-kneaded by the above method.

Polyester resin composition (D) of the present invention
Other resins, specifically, polyolefins such as polyethylene and polypropylene, various elastomers such as polyolefin elastomers and polyamide elastomers, and ionomers may be added to the above-mentioned range, so long as the effects of the present invention are not impaired. Further, additives such as pigments, dyes, lubricants, matting agents, heat stabilizers, weather resistance stabilizers, ultraviolet absorbers, nucleating agents, plasticizers, flame retardants and antistatic agents can also be added. In addition, the polyester resin composition (D) of the present invention contains a polyethylene terephthalate product recovery product, a modified polyethylene terephthalate product recovery product containing a small amount of isophthalic acid component units, and a polyamide product recovery product, as long as the properties thereof are not essentially changed. And / or polyester and / or polyamide resin recovery products such as nonstandard products may be added.

In addition, the gas barrier property of the resin composition may be improved by adding a clay mineral such as montmorillonite or an organic transition metal such as cobalt stearate during mixing.

Molded Articles Molded articles comprising the polyester resin composition (D) of the present invention include extrusion molded articles and injection molded articles, and films and sheets obtained by uniaxially stretching or biaxially stretching the extrusion molded articles and injection molded articles. Examples include thin hollow containers that have been stretch-blown. That is, the polyester resin composition (D) of the present invention is a non-stretched or low-strength single-layer sheet or multi-layer sheet obtained by T-die method, co-extrusion method, etc. Film and deep-drawing container, and high transparency such as a thin hollow container having a body wall thickness of 0.1 to 2 mm obtained by direct blow molding and stretch blow molding that is in an unstretched state even after molding. It can be used as a required material for a molded article for packaging.

The hollow molded article can be molded in the same manner as the conventional hollow molding method for polyester resin.
For example, in extrusion blow molding generally called direct blow or injection blow molding, there is a method of blow molding with a compressed gas before injection molding the parison before it is sufficiently cooled (hot parison method), or by injection molding or extrusion molding. A method (cold parison method) in which a parison having a bottom opening is produced, and then the parison is temperature-controlled by a stretching blow device to an appropriate temperature for stretching and biaxial stretching with a compressed gas is performed simultaneously or sequentially and then blow molding is performed (cold parison method) can be used.

Polyester resin composition (D) of the present invention
Is a non-stretched or low-strength single-layer sheet or multi-layer sheet obtained by T-die method, co-extrusion method, etc., a film obtained by stretching them, a low-stretching ratio deep-draw molding container, or a non-stretched state after molding Direct blow molded containers, and good moldability to stretch blow molded containers and the like, and, while maintaining the gas barrier properties and high color tone of the obtained film, sheet and thin hollow container, excellent transparency in the molded body, Pinhole resistance and whitening resistance when absorbing moisture can be imparted. Further, the polyester-based gas barrier hollow molded article of the present invention can be used for food packaging containers, pharmaceutical packaging containers, tanks for fuel such as gasoline, containers for perfume / dye / cosmetics, containers for solvents and the like.

[0046]

EXAMPLES Next, the present invention will be described more specifically by way of Examples and Comparative Examples. The methods for synthesizing the samples [polyamide resin (A), polyethylene terephthalate resin (C)] and the samples [polyester resin (B)] used in each example and comparative example, and the method for evaluating the obtained polyester resin composition are as follows. It is as follows.

[Sample] In each Example and Comparative Example,
MDX6 as a polyamide resin (A) (manufactured by Mitsubishi Gas Chemical Co., Inc., trade name: MX nylon 6011, relative viscosity:
2.65, hereinafter referred to as "MX nylon". )It was used. As polyethylene terephthalate resin (C), manufactured by Nippon Unipet Co., Ltd., trade name: UNIPET, grade RT553C (intrinsic viscosity 0.80 (dl / g),
Hereinafter referred to as "PET". )It was used.

[Sample Synthesis Method] As the polyester resin (B), those obtained by polycondensing the dicarboxylic acid monomer and the diol monomer shown in Tables 1 to 12 were used. sample
The [polyester resin (B)] was synthesized by the following two-step reaction. (1) DMT transesterification reaction Predetermined amounts of the raw material monomers listed in Tables 1 to 12 and terephthalic acid dimethyl ester (D
MT) 100 mol of manganese acetate tetrahydrate 0.03
Under a nitrogen and nitrogen atmosphere, the temperature was raised to 200 ° C. to carry out a transesterification reaction. The reaction was continued until the amount of methanol produced by the transesterification reaction reached 90% or more of the theoretical amount. (2) Polycondensation reaction Next, with respect to 100 mol of DMT charged in the preceding step, 0.01 mol of antimony (III) oxide as a polycondensation reaction catalyst and triphenyl phosphate (hereinafter, referred to as an antioxidant)
0.06 mol (referred to as "TPP") was added, the temperature was raised and the pressure was gradually reduced, and finally polymerization was performed at 280 ° C and 0.1 kPa or less. The reaction was terminated when the melt viscosity became appropriate, and a polyester resin (B) was obtained.

[Evaluation Method] Evaluation methods of the resin compositions obtained in the examples and comparative examples are as follows. (1) Haze value (haze) and yellowness (YI) Haze value and yellowness are JIS-K-7105 and AS, respectively.
It carried out according to TM D1003. The measuring device used is a haze value measuring device (model: COH- manufactured by Nippon Denshoku Industries Co., Ltd.
300A). (A) Measurement of haze value of unstretched sheet: sheet thickness 300 μ
After conditioning humidity for 48 hours, 23 ℃, relative humidity 50%
Was measured under the atmosphere. The values in the table are values converted into thickness of 20 μm. (B) Measurement of haze value of stretched sheet: An unstretched sheet was stretched 4 times in the transverse direction and 4 times in the longitudinal direction, and heat-set at 220 ° C. A sheet with a thickness of about 20 μm was conditioned for 48 hours.
The measurement was performed in an atmosphere of 23 ° C. and a relative humidity of 50%. In addition,
The values in the table are values converted into thickness of 20 μm. (C) Measurement of haze value and yellowness of bottle: The body of the prepared bottle was cut out and the haze value and yellowness were measured. The measured value was converted to a thickness of 300 μm. The unit of the measured value is%.

(2) Oxygen permeability coefficient It was carried out in accordance with ASTM D3985. The measuring device is manufactured by Modern Controls (Model: OX-TRAN10 /
50A) was used. The measurement conditions were a temperature of 23 ° C. and a relative humidity of 60%. The unit of measurement value is ml · mm /
m ² · day · atm.

(3) Impact re-drilling test It was conducted according to JIS P813, ASTM D781. As a measuring instrument, a puncture tester manufactured by Toyo Seiki Co., Ltd. was used. The measurement conditions were a temperature of 23 ° C. and a relative humidity of 50%. The unit of the measured value is kJ / m.

(4) As a pinhole resistance measuring device, Gelbo Flex manufactured by Rigaku Kogyo Co., Ltd. was used, and pinholes were measured at 200 times, 400 times and 800 times. The axial direction of Gerboflex was used as the measurement direction. The pinhole was measured using a pinhole tester (weak current discharge method). Measurement environment is temperature 2
The temperature was 3 ° C. and the relative humidity was 50%.

The following symbols are used in the tables showing conditions and results of Examples and Comparative Examples. The mark * has a cyclic acetal skeleton. "PET": polyethylene terephthalate "DMT": dimethyl terephthalate "SPD" ^* : 3,9-bis (2-carboxyethyl)
2,4,8,10-Tetraoxaspiro [5,5] undecane "DOD" ^* : 5-methylol-5-ethyl-2-
(1,1-dimethyl-2-carboxoxyethyl)-
1,3-dioxane "EG": ethylene glycol "CHDM": 1,4-cyclohexanedimethanol "SPG" ^* : 3,9-bis (1,1-dimethyl-2-
Hydroxyethyl) 2,4,8,10-tetraoxaspiro [5,5] undecane "DOG" ^* : 5-methylol-5-ethyl-2-
(1,1-dimethyl-2-hydroxyethyl) -1,3
-Dioxane

Examples 1 to 10 and Comparative Examples 1 to 6 A predetermined amount of polyamide resin (A) and polyester resin (B) were mixed by a tumbler. This mixture was mixed with a twin-screw extruder (screw diameter: 20 mmφ, L / D: 25).
Cylinder temperature 240-260 by T-die method
℃, T die temperature 280 ℃, screw rotation speed 50 rp
m, the film was formed under the conditions of a cooling roll temperature of 70 to 80 ° C. to obtain an unstretched sheet having a width of 120 mm and a thickness of about 0.3 mm.
The haze values of the obtained sheets are shown in Tables 1-5. Then, using a biaxial stretching machine manufactured by Toyo Seiki Co., 9
After preheating at 0 to 110 ° C. for 10 to 30 seconds, the film was simultaneously stretched in the longitudinal and transverse directions at a linear stretching speed of 30 to 90% / sec and a stretching ratio of 4.0 in the longitudinal and transverse directions.
Then, the stretched film is kept under tension 23
Heat treatment was performed for 20 seconds in an atmosphere of 5 to 240 ° C. to obtain a stretched film having a thickness of 20 μm. The evaluation results of the obtained film are shown in Tables 1 to 5.

Examples 11 to 17 and Comparative Examples 7 to 8 A predetermined amount of polyamide resin (A), polyester resin (B) and polyethylene terephthalate resin (C) were mixed by a tumbler. Using a twin-screw extruder (screw diameter: 20 mmφ, L / D: 25),
A film is formed by a T-die method under the conditions of a cylinder temperature of 240 to 260 ° C, a T-die temperature of 260 ° C, a screw rotation speed of 50 rpm, and a cooling roll temperature of 70 to 80 ° C, and a width of 120 m.
An unstretched sheet having a thickness of m and a thickness of about 0.3 mm was obtained. The haze value of the obtained sheet is shown in the table. Then, using a biaxial stretching machine manufactured by Toyo Seiki Co., the stretched sheet is preheated at 95 to 115 ° C. for 10 to 30 seconds, and then the linear stretching speed is 30 to 90.
% / Sec, and the stretching ratios in the longitudinal and transverse directions were each 4.0 times, and the film was simultaneously stretched in the longitudinal and transverse directions. Then, the stretched film was heat-treated in an atmosphere of 235 to 240 ° C. for 20 seconds while keeping the stretched film to obtain a stretched film having a thickness of 20 μm. The evaluation results of the obtained film are shown in Table 6-
8 shows.

Examples 18 to 20 A predetermined amount of polyamide resin (A) and polyester resin (B) were mixed by a tumbler. This mixture was mixed with a twin-screw extruder (screw diameter: 38 mmφ, L / D: 25).
Cylinder temperature 240-260 ℃, die temperature 2
Pellets of the melt-kneaded product were prepared under the conditions of 60 ° C. and screw rotation speed of 200 rpm. A predetermined amount of the melt-kneaded product and the polyethylene terephthalate resin (C) were mixed by a tumbler, and the mixture was used, using a twin-screw extruder (screw diameter: 20 mmφ, L / D: 25), and a cylinder temperature of 240 to 260 ℃, T die temperature 260
℃, screw rotation speed 50 rpm, cooling roll temperature 70
The film is formed under the condition of -80 ° C, the width is 120 mm, and the thickness is about 0.
A 3 mm unstretched sheet was obtained. The haze value of the obtained sheet is shown in the table. Then, using a biaxial stretching machine manufactured by Toyo Seiki Co.,
After pre-heating the stretched sheet only at 95 to 115 ° C. for 10 to 30 seconds, the linear stretching rate is 30 to 90% / sec, and the stretching ratio in the longitudinal and transverse directions is 4.0 times, respectively, in the longitudinal and transverse directions. Simultaneously stretched. Then, the stretched film is kept under tension in an atmosphere of 235 to 240 ° C. for 20 minutes.
Heat treatment was performed for 2 seconds to obtain a stretched film having a thickness of 20 μm. Table 9 shows the evaluation results of the obtained film.

Examples 21 to 28, Comparative Examples 9 to 11 A predetermined amount of polyamide resin (A), polyester resin (B) and polyethylene terephthalate resin (C) were mixed by a tumbler. An injection molding machine (model: M200) manufactured by Meiki Seisakusho Co., Ltd. was used to mold a preform having a weight of 30 g. Next, a blow molding machine (model: LB-01) manufactured by Krupp Corpoplast (Germany) was used to mold a bottle having a volume of 500 mL (pressure resistant specification, petaloid bottom mold) by blow molding. Tables 10 to 12 show the measurement results of the haze value and YI value of the bottle body of the obtained hollow container, and the oxygen permeability coefficient.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

[0062]

[Table 5]

[0063]

[Table 6]

[0064]

[Table 7]

[0065]

[Table 8]

[0066]

[Table 9]

[0067]

[Table 10]

[0068]

[Table 11]

[0069]

[Table 12]

[0070]

The polyester resin composition of the present invention is
It can be used for films, sheets, thin hollow containers, etc. having excellent gas barrier properties, transparency, color tone, and pinhole resistance. Therefore, the industrial value of the present invention is high.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B29K 67:00 B29K 67:00 77:00 77:00 B29L 7:00 B29L 7:00 (72) Inventor Takeshi Hirokane 5-6-2 Higashi-Hachiman, Hiratsuka-shi, Kanagawa Sanritsu Gas Chemical Co., Ltd. Hiratsuka Laboratory (72) Inventor Masahiro Kurokawa 5-6-2, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Sanritsu Gas Chemical Co., Ltd. In-house F-term (reference) 4F071 AA44 AA54 AF07 AF30 AH05 BB05 BB06 BB08 BC01 BC04 4F207 AA24 AA29 AG01 KA01 KA17 4J002 CF05X CF06Y CL01W CL03W GG01

Claims (18)

[Claims] 1. A polyamide resin (A) and a polyester resin (B), or a polyamide resin (A), a polyester resin (B) and a polyethylene terephthalate resin (C).
A polyester resin composition (D) comprising
The polyester resin (B) contains a dicarboxylic acid component containing 0.5 to 60 mol% of a dicarboxylic acid having a cyclic acetal skeleton and / or a diol component containing 0.5 to 60 mol% of a diol having a cyclic acetal skeleton. It is a polyester resin obtained by condensation, and the blending ratio of each component is such that the polyamide resin (A) is 1 with respect to the total weight of the polyamide resin (A), the polyester resin (B) and the polyethylene terephthalate resin (C). To 99% by weight, the polyester resin (B) is 1 to 99% by weight, and the polyethylene terephthalate resin (C) is 0 to 98% by weight. 2. The polyamide resin (A) is a polyamide resin obtained by polycondensing a diamine component containing metaxylylenediamine in an amount of 70 mol% or more and a dicarboxylic acid component containing adipic acid in an amount of 70 mol% or more. 1. The polyester resin composition according to 1. 3. The polyester according to claim 1, wherein the polyester resin (B) is a polyester resin obtained by polymerization using a dicarboxylic acid component containing 70 mol% or more of an aromatic dicarboxylic acid. -Based resin composition. 4. The polyester resin composition according to claim 3, wherein the aromatic dicarboxylic acid is terephthalic acid or an ester thereof. 5. The polyester resin composition according to claim 1, wherein the diol having a cyclic acetal skeleton is a compound represented by the general formula (1) and / or the general formula (2). [Chemical 1] [Chemical 2] However, R in the general formula (1) and the general formula (2),
R'is an organic group selected from the group consisting of an aliphatic group having 1 to 10 carbon atoms, an alicyclic group and an aromatic group. 6. A diol having a cyclic acetal skeleton,
3,9-Bis (1,1-dimethyl-2-hydroxyethyl) 2,4,8,10-tetraoxaspiro [5.5]
Undecane and / or 5-methylol-5-ethyl-2- (1,1-dimethyl-2-hydroxyethyl)-
The polyester resin composition according to claim 5, which is 1,3-dioxane. 7. The polyester resin composition according to claim 1, wherein the dicarboxylic acid having a cyclic acetal skeleton is a compound represented by the general formula (3) and / or the general formula (4). [Chemical 3] [Chemical 4] However, R in the general formula (3) and the general formula (4),
R'and R "are organic groups selected from the group consisting of aliphatic groups having 1 to 10 carbon atoms, alicyclic groups and aromatic groups, and R"'
Is H, a methyl group, an ethyl group, or an isopropyl group. 8. A dicarboxylic acid having a cyclic acetal skeleton is 3,9-bis (2-carboxyethyl) 2,4.
8,10-Tetraoxaspiro [5.5] undecane and / or 5-methylol-5-ethyl-2- (1,
The polyester resin composition according to claim 7, which is 1-dimethyl-2-carboxyethyl) -1,3-dioxane. 9. The polyester resin (B) comprises a dicarboxylic acid component containing 1 to 20 mol% of a dicarboxylic acid having a cyclic acetal skeleton and / or a diol component containing 1 to 20 mol% of a diol having a cyclic acetal skeleton. A polyester resin obtained by polymerization of
8. The polyester resin composition according to any of 8. 10. The blending ratio of each component of the polyester resin composition (D) is such that the polyamide resin (A) is 1 to 50% by weight, the polyester resin (B) is 1 to 79% by weight, and the polyethylene terephthalate resin (C). ) Is in the range of 20 to 98% by weight, the polyester resin composition according to any one of claims 1 to 8. 11. The mixing ratio of each component of the polyester resin composition (D) is 5 to 45% by weight of the polyamide resin (A), 5 to 45% by weight of the polyester resin (B), and a polyethylene terephthalate resin (C). ) Is in the range of 50 to 90% by weight, the polyester resin composition according to claim 10. 12. The blending ratio of each component of the polyester resin composition (D) is in the range of 5 to 95% by weight of the polyamide resin (A) and 5 to 95% by weight of the polyester resin (B). The polyester resin composition according to claim 1, wherein the terephthalate resin (C) is 0% by weight. 13. A polyamide resin (A) and a polyester resin (B), or a mixture obtained by dry-blending a polyamide resin (A), a polyester resin (B) and a polyethylene terephthalate resin (C) is melt-kneaded. The polyester resin composition according to any one of 1 to 12. 14. A melt-kneaded mixture of a pre-kneaded product obtained by melt-kneading a polyamide resin (A) and a polyester resin (B) and a dry-blended mixture of a polyethylene terephthalate resin (C). The polyester-based resin composition described in 1. 15. An extruded product comprising the polyester resin composition according to claim 1. 16. A polyester film obtained by uniaxially or biaxially stretching the extruded product according to claim 15. 17. An injection-molded article made of the polyester resin composition according to claim 1. 18. A polyester hollow molded article obtained by stretch-blowing the injection molded article according to claim 17.