JPH01201326A - Polyester molding material and molding - Google Patents

Abstract

PURPOSE:To obtain the title molding material improved in gas barrier property and heat resistance and made suitable as a packaging material for foods, cosmetics, medicines, etc., by constituting it from a specified acid component and a specified diol component. CONSTITUTION:The title molding material is an aromatic polyester comprising isophthalic acid as an acid component and resorcinol as a diol component (having an intrinsic viscosity of, desirably, >=0.3, especially, 0.4-1.5 when measured in a phenol/tetrachloroethane mixed solvent of a weight ratio 60/40 at 35 deg.C) or a copolymer polyester containing at least 60mol.%, desirably, at least 75mol.% said repeating units. Although this aromatic polyester can serve by itself as a packaging material for films and sheets, the gas barrier property can be improved further in the case of hollow moldings such as bottles when a composition formed by mixing 100pts.wt. this aromatic polyester with 1-100pts. polyethylene terephthalate is used.

Description

[Detailed description of the invention] Sensei Yu! Prevention of Warpage 1 The present invention relates to a polyester molding material with excellent gas barrier properties and heat resistance.The polyester molding material of the present invention is suitable for packaging materials such as films and containers for foods, cosmetics, pharmaceuticals, etc. In addition to being used as single-layer films and containers, it can also be blended with other materials such as polyethylene terephthalate and used as molded products for films and containers.

・Polyethylene terephthalate is widely used as a packaging material for headphone films and containers.In the packaging of foods, beverages, etc., gas barriers are used to preserve the taste and aroma of the contents. -Gender is required.

In addition, due to the disadvantages of retort food, heat resistance and chemical resistance that can withstand sterilization and disinfection are also required qualities. However, although polyethylene terephthalate, which is a general-purpose material, can be said to have higher gas barrier properties than olefin resins such as polyethylene, it has poor gas barrier properties compared to conventionally used glass containers, aluminum foil, etc. can be said to be inferior. Therefore, the gas barrier properties of polyethylene terephthalate cannot be said to be sufficient.

Therefore, methods for improving the gas barrier properties of polyethylene terephthalate have been investigated.

For example, there is a method of coating and laminating materials with excellent gas barrier properties. Polyvinylidene chloride.

polyethylene - saponified vinyl acetate (vinyl alcohol)
Since these polymers have better gas barrier properties than polyethylene terephthalate, these polymers are laminated (see Japanese Patent Publication No. 117565/1986,
6-64839), or biaxially oriented bottles made of three or five sandwich layers of nylon resin having excellent gas barrier properties and polyethylene terephthalate are also known.

Films and containers have improved gas barrier properties when subjected to thermoforming or stretch orientation. Therefore, if a material with excellent gas barrier properties can be used alone, it must have moldability (film-forming ability) that can be processed by thermoforming, stretching (oriented blowing), etc. It won't happen,
If it is not used alone, it is applied as a laminate or a polymer blend, so it is required to be moldable and stretchable at the same time as the polyethylene terephthalate base material. However, to date, the molding materials that have excellent barrier effects that can be used to improve film moldability and improve the gas barrier properties of polyethylene terephthalate have extremely low f-values. When it comes to heat-resistant molding materials for films and bottles (containers) that can be used for retort food packaging and fruit juice filling, it is still unknown whether they are practical or not.

Book 1 - Summary 1 The object of the present invention is to provide an aromatic polyester molding material suitable for a new molding material having heat resistance and gas barrier properties.

The molding material of the present invention can be molded as a single component into packaging molded products such as films and containers. Further, the molding material of the present invention can be used as a film or a container by laminating it with polyethylene terephthalate. Furthermore, the molding material of the present invention can be appropriately blended with a known packaging material such as polyethylene terephthalate to form a polymer blend (
Because it exhibits high gas barrier properties as a polyester composition, it can also be put to practical use as a packaging molded product made of a resin composition.4For example, this polyester composition can be used not only for single-layer films and bottles, but also for other suitable applications. It can be used by laminating it with a base material (polyethylene terephthalate base layer).

In the present invention, a molded article with excellent heat resistance and gas barrier properties can be obtained by processing an aromatic polyester having heat resistance and gas barrier properties into a packaging molded article in the form of a pomopolymer, copolymer, or polymer blend. This is a technical problem to be solved.

It has been found that aromatic polyester containing the following chemical structure <I) in its repeating units has excellent heat resistance and gas barrier properties.

The molding material of the present invention is an aromatic polyester containing isophthalic acid as the main acid component and resorcinol as the main diol component. , preferably 75 mol% or more. Therefore, the molding material of the present invention is
A copolymerized polyester represented by the following formula (II) is also included. Here, X and Y are divalent organic groups, and m or n is an integer of 1 or more. The esul unit which becomes a copolymerization component is 4 in the case of aromatic
0 mol% or less, 20 mol% for alicyclics and aliphatics
The following is preferred.

Such copolymerizable components include dicarboxylic acid diols and oxyacids other than isophthalic acid and resorcinol, and examples that can be specifically copolymerized include aromatic dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, and diphenyldicarboxylic acid.

Diphenoxyethane dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenylgetone dicarboxylic acid, sodium-sulfoisophthalic acid, dibromoterephthalic acid, etc.: Alicyclic dicarboxylic acid 1, e.g., decalin dicarboxylic acid, hehisahydroterephthalic acid, etc.: Aliphatic dicarboxylic acids 1 such as malonic acid, succinic acid.

Adipic acid, etc.; aliphatic diols such as ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol.

Neopentyl glycol, diethylene glycol, etc.: Aromatic diols, such as hydroquinone, catechol, naphthalene diol, bisphenol A [2,2-bis(
4-hydroxyphenyl)propane], bisphenol S, tetrabromobisphenol A, bishydroxyethoxybisphenol A, etc.: Alicyclic diols, e.g.
Cyclohexanediol, etc.: Aliphatic oxycarboxylic acid 1
For example, glycolic acid, hydroacrylic acid, 3-oxypropionic acid, etc.: Alicyclic oxycarboxylic acid 9 For example, asiatic acid, quinobic acid, etc.; Aromatic oxycarboxylic acid 2 For example, salicylic acid 1 m-oxybenzoic acid, p-oxy Examples include benzoic acid, mandelic acid, atrolactin acid, and the like.

Furthermore, within the range where the polyester is substantially linear, a trivalent or higher valent polycyclic digested compound 1, for example, glycerin.

Trimethylolpropane, pentaerythritol.

trimellitic acid, trimesic acid, pyromellitic acid.

Tricarballylic acid, gallic acid, etc. may be copolymerized, or monofunctional compounds 9 such as 0-benzoylbenzoic acid, naphthoic acid, etc. may be added.

The aromatic polyester of the present invention can be manufactured by conventional techniques accumulated regarding polyester manufacturing methods. For example, it can be manufactured by polycondensation (dephenolization) using diphenyl isophthalate and resorcinol. It can also be produced by polycondensation (deacetic acid removal) using isophthalic acid and resorcin diacetate. Furthermore, interfacial polymerization of isophthalic acid dichloride and resorcinol can of course be applied. During these reactions, it is preferable to use a polycondensation catalyst, a thermal stabilizer, etc. As these catalysts, stabilizers, etc., those known as polyester catalysts and stabilizers can be used. also,
If necessary, additives 9 such as colorants, optical brighteners, antioxidants, ultraviolet absorbers, antistatic agents, R-fuel agents, etc. may be used.

The aromatic polyester of the present invention preferably has an intrinsic viscosity (measured at 35°C using a mixed solvent of phenol/tetrachloroethane in a weight ratio of 60/40) of 0.3 or more, particularly 0.4 to 1. It is preferable that it is in the range of 5.

Next, embodiments of the present invention will be described.

The aromatic polyester of the present invention is an amorphous polymer and can be used alone as a sheet-like packaging material such as a film. In addition, the aromatic polyester of the present invention can be used as a polymer blend or laminated film with other amorphous or crystalline self-retaining polymers (for example, polyethylene terephthalate) and formed into desired molded products. It can be applied to containers made of polyethylene terephthalate, such as hollow molded bodies such as bottles. Such a blow molded article is made of a polyester (A) which is a known material and consists essentially of polyethylene terephthalate, and a polyester (B) in which aromatic ester units of the present invention account for at least 60 mol% of the repeating units. It is preferable to use a polyester resin composition containing 1 to 100 parts by weight of the latter to 100 parts by weight of the former because the gas barrier properties are further improved.

Here, the polyester (A) is essentially polyethylene terephthalate, and may contain a small amount of 10 mol% or less of other ester units (other than ethylene terephthalate). Small amounts of copolymerization components within 10 mol % include dicarboxylic acids other than terephthalic acid, diols other than ethylene glycol, and oxyacids. Specific examples include aromatic dicarboxylic acids such as isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenylsulfone dicarboxylic acid, and diphenyl ketone dicarboxylic acid. Sodium-sulfoisophthalic acid, dibromoterephthalic acid, etc.: Alicyclic dicarboxylic acids 9 For example, decalindicarboxylic acid, hehisahydroterephthalic acid, etc.; Aliphatic dicarboxylic acids.

For example, malonic acid, succinic acid, adipic acid, etc.; aliphatic diols, such as trimethylene glycol.

Tetramethylene glycol, hexamethylene glycol, neopentyl glycol, diethylene glycol, etc.:
Aromatic diols, such as hydroquinone, catechol,
Naphthalene diol, bisphenol A [2,2-bis(4-hydroxyphenyl)propaneco, bisphenol S, tetrabromobisphenol A, bishydroxyethoxybisphenol A, etc.: Alicyclic diol, for example, cyclohexanediol, etc.: Aliphatic oxycarbonate Acids 1 For example, glycolic acid, hydroacrylic acid.

3-oxypropionic acid, etc.; alicyclic oxycarboxylic acid 1
For example, asiatic acid, quinobic acid, etc.: Aromatic oxycarboxylic acid 1 For example, salicyl [i! , m-oxybenzoic acid, p-oxybenzoic acid, formalic acid, mandelic acid, atrolactic acid, and the like.

Among these, a homopolymer of polyethylene terephthalate is preferable. Polyethylene terephthalate is suitable for the moldability of an amorphous preform (preform), the stretchability during blow molding, and the mechanical properties of the resulting blow molded product. Considering that, the intrinsic viscosity ([η], orthochlorophenol, 35°C) is 0.5 to 1.2, more preferably 0.6 to 1.
Of course, in addition to these hollow molded containers, molded products such as sheet-like packaging materials and food containers such as cups and trays obtained by deep drawing sheet-like materials can also be used. The intrinsic viscosity of the polyester (A) is preferably within the above range.

In the present invention, when polyethylene terephthalate polyester (A) and polyester (B) consisting of a homopolymer or copolymer represented by formula (I) or formula (n) are mixed, 100 parts by weight of the former is used. On the other hand, it is necessary to add 1 to 100 parts by weight of the latter.

If the amount of polyester (B) is less than 1 part by weight, the effect of improving gas barrier properties will not appear, and if it exceeds 100 parts by weight, the molded product and mechanical strength of polyester (A) will be impaired, which is not preferable.

The polyester resin composition of the present invention is preferably melt-kneaded using an extruder to obtain a mixed pellet and then used for preform molding. It can also be applied directly to preform molding.

The molded products of the present invention include sheets, films, thick-walled containers, trays, etc. made only of aromatic polyester.
The aromatic polyester of the present invention is an amorphous thermoplastic resin, and becomes thermoplastic at temperatures of about 110 to 120°C or higher.

In addition, in the case of a molded article of the present invention that also includes a molded article obtained from a molding material as a blend of polyester (A) and aromatic polyester, the molded article may be modified depending on the blending ratio of the aromatic polyester. Although the conditions change slightly, it is extremely compatible with polyethylene terephthalate polyester, so it can be molded at a slightly higher molding temperature. Such molded products include hollow molded products, (single layer,
(multi-layer), deep-drawn thermoformed sheet tray.

Examples include cups.

[Effects of the Invention] The aromatic polyester of the present invention has excellent gas barrier properties and heat resistance.9 For example, the carbon dioxide gas permeability coefficient is approximately 1/10 or less of that of polyethylene terephthalate, which is extremely excellent. I understand. Also, the glass transition point is 1
00°C, it has heat resistance as a packaging material and can be applied to retort food color packaging.1 The aromatic polyester of the present invention can be used alone or in a laminate or blend with other resins (
Can be used as compositions), sheets, films, and trays.

It can be made into molded products such as cups and bottles. Of course, it is also possible to use or mix the color with a molding material having gas barrier properties.

[Example] The present invention will be described in detail below with reference to Examples.

Here, "parts" in the examples mean parts by weight.

The methods for measuring characteristics used in the examples are shown below.

0 Intrinsic viscosity [η] The aromatic polyester was calculated from the solution viscosity measured at 35° C. using a mixed solvent of phenol/tetrachloroethane (60/40 weight ratio).

Polyethylene terephthalate (polyester A) was measured at 35°C using O-chlorophenol as a solvent.

OTg (glass transition temperature) A sample was prepared by heating the polymer to 280°C and rapidly cooling it in ice water.
Value measured using DSC1090B) at a heating rate of 20°C/min.

0 Carbon dioxide gas permeability coefficient: Pco□ Melt extrude the polymer to create a 250 μm unstretched film, heat it to 120 to 140°C with a long stretching machine, and double the film in two axial directions at the same time by 3.5 x 3.5 times. Without stretching, the obtained biaxially stretched film was tested at 30° at -315-N-03 using a gas permeation measuring device manufactured by Rika VT Kikogyo ■.
The permeability coefficient of carbon dioxide gas (CO2 gas) was measured at C.

O-Bottle Drop Impact Resistance After filling a bottle with 1000g of water and 14g of citric acid, we weighed it into a polyethylene bag and placed 1 of bicarbonate of soda.
4 g was inserted into the mouth of the bottle without directly mixing it with the aqueous citric acid solution in the bottle, and the bottle was immediately capped with an aluminum cap. After capping, the bottle was shaken so that the sodium bicarbonate and citric acid aqueous solution inserted into the bottle were sufficiently mixed to generate CO□, and an aqueous solution in which CO□ was dissolved under pressure was filled into the bottle. state.

The CO2-filled bottle was kept at 5°C, and after 24 hours, the bottle was dropped from a height of 1.5 meters onto a concrete floor with the bottom facing downward, and the rupture rate of the bottle was examined.

0 Carbon dioxide gas barrier properties of bottles.
A bottle filled with CO2 in which 24.0 times Volume was dissolved under pressure in a container 120 was held in an atmosphere of a predetermined temperature and humidity for a predetermined time, and then the filled bottle was transferred to an atmosphere of 20°C.
The remaining CO2 Volume was measured by measuring the Co2 pressure inside the bottle while the content liquid temperature was 20°C.

However, co□lJolume=Vo02/■H2゜Example 1 159 parts of diphenyl isophthalate and 55 parts of resorcin were placed in a flask that had been exchanged with Nzt several times, and heated at 260°C under a stream of N2.
The temperature rises to After 1 hour, the temperature was gradually raised to 280°C and held for about 30 minutes. After that, a weak vacuum (~30+u
After reacting for 1 hour under +H(1), further high vacuum (~1
mllljJ) for 1.5 hours. The obtained polymer had a [η] of 0.50 and a brown color.

Carbon dioxide permeability coefficient is 0.9X -・cIl/-・Sec
・■HQ, and the glass transition temperature is 110°C'''
There was C''.

In addition, polyethylene terephthalate with [η] 0.61:・
The carbon dioxide permeability coefficient is 18×10″L21・cm/d・
SeC·aoH (1″'C″), and the glass transition temperature was 85°C.

Therefore, it was found that this polymer has better gas barrier properties than polyethylene terephthalate.

Examples 2 to 6 and comparative examples 1 to 2 Polyethylene terephthalate (hereinafter abbreviated as PET) ([ηconi 0.75,
T! ; 1=69°C), and an aromatic polyester (B
) Melt and mix in the proportions shown in Table 1, molding temperature 270-28
Injection molded at 0℃ and mold temperature 10℃, the outer diameter of the cylindrical body is 25~26cm, the wall thickness is 3.5+++m, and the total length is 155cm.
A preform having a bottomed end was obtained.

Biaxial stretch blow molding of the preform 8! l (Blow molding with RHB-L type n manufactured by Cincinnati Milacron Co., Ltd. at a preform heating temperature of 110 to 140°C to obtain a body with an outer diameter of 82
n+m, total height 280m+n, body thickness 320-380μ
A bottle with an internal volume of 1040 to 10105 O was obtained.

The resulting polyester bottle was evaluated for drop impact strength and carbon dioxide gas barrier properties. The results are shown in Table 1.

The bottles of the invention shown in Examples 2-6 have excellent CO2
It was found that it not only has barrier properties but also has strength that does not pose a problem in practical use.

Example 7 and grain ratio example 3 Same as Example 4 except that a polyester copolymer obtained by condensing resorcin, isophthalic acid, and terephthalic acid was used instead of polyester (B) obtained by condensing resorcin and isophthalic acid. I did the same.

The results are shown in Table 2.

Table 2 M ring (overlapping part): Polyester (8) [PET]
: Polyester + B) -30: Shown as a molar ratio of 100.

It was found that aromatic polyester also contributed to the drop [2] strength.

Procedural amendment May/7th, 1986

Claims (1)

[Claims] 1. A molding material made of an aromatic polyester containing isophthalic acid as the main acid component and resorcinol as the main diol component. 2. 1 to 100 parts by weight of the aromatic polyester according to claim 1 and 100 parts by weight of the polyethylene terephthalate polyester
A molding material for a resin composition consisting of parts by weight. 3. A molded article containing the aromatic polyester obtained by molding the aromatic polyester according to claim 1 or the molding material of the resin composition according to claim 2.