JPS61241350A - Polyester composition and use thereof - Google Patents

Abstract

PURPOSE:A composition, obtained by incorporating a polyalkylene terephthalate with a specific cocodensed polyester, having improved melt moldability and mechanical strength and transparency and gas barrier properties and useful as a material for containers. CONSTITUTION:A composition obtained by incorporating (A) a polyalkylene terephthalate consisting essentially of ethylene terephthalate as main constituent units with (B) a substantially linear cocondensed polyester consisting of 25-48mol% aromatic dicarboxylic acid component consisting essentially of isophthalic acid and 45-50mol% diol component consisting essentially of ethylene glycol, 2-25mol% <=12C aromatic hydroxycarboxylic acid component and 0-2mol% 3-15C polyfunctional compound having >=3 carboxyl or hydroxyl groups and having 0.5-1.5dl/g intrinsic viscosity and 50-120 deg.C glass transition temperature.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a polyester composition that has excellent melt moldability, excellent mechanical strength, transparency, and gas barrier properties, and has excellent performance as a material for containers. and its uses.

[Conventional technology]

Traditionally, glass has been widely used as a container material for seasonings, oils, beer, alcoholic beverages such as sake, soft drinks such as carbonated drinks, cosmetics, detergents, and other products. However, although glass containers have excellent gas barrier properties, they are expensive to manufacture, so a method has been adopted in which empty containers are usually collected after use and recycled for reuse. However, glass containers are heavy, which increases shipping costs, and they also have drawbacks such as being easily damaged and inconvenient to handle.

In order to overcome the aforementioned disadvantages of glass containers, there is a growing shift from glass containers to various plastic containers. Various plastics are used as materials depending on the type of stored item and its intended use. Among these plastic materials, polyethylene terephthalate has excellent gas barrier properties and transparency, and is therefore used as a material for containers for seasonings, soft drinks, detergents, cosmetics, and the like. However, polyethylene terephthalate is still not sufficient for beer and carbonated beverage containers, which require the most stringent gas barrier properties, and it is necessary to use thicker polyethylene terephthalate for use in these containers. The gas barrier properties had to be improved by increasing the amount of carbon. Currently, the demand for polyester containers is increasing, and in order to expand these uses, there is a strong demand for polyesters that have excellent gas barrier properties and excellent melt moldability.

JP-A-59-64624 discloses polyisophthalates such as poly(ethylene isophthalate), polymers thereof, and molded articles formed therefrom as packaging materials having good gas barrier properties against oxygen and carbon dioxide. is disclosed.

Japanese Unexamined Patent Publication No. 59-670 filed by the same applicant as the above application
Publication No. 49 discloses a multilayer packaging material made of a layer made of polyisophthalate or a copolymer thereof as described above and a layer made of a polyterephthalate such as poly(ethylene terephthalate) or a copolymer thereof, and a molded product made thereof, such as a bottle. ing.

Furthermore, JP-A-59-39547 discloses that the innermost layer is made of polyester whose main repeating unit is ethylene terephthalate, the outer layer is made of polyester whose main repeating unit is ethylene isophthalate, and the thinner part of the container is at least A multilayer container with excellent gas permeation resistance that is oriented in one direction is disclosed.

As a material different from polyester, JP-A-48-362
Publication No. 96 discloses a transparent product containing toxylylene diamine or a mixture of p-xylylene diamine and p-xylylene diamine as a diamine component, and a mixture of a specific aromatic dicarboxylic acid and an aliphatic dicarboxylic acid as a dicarboxylic acid component. A polyamide with good properties is disclosed. The publication describes that the polyamide has good impact strength and excellent processability, but there is no mention of its gas barrier properties.

JP-A-56-64866 discloses that the outermost layer and the innermost layer are made of polyester having ethylene terephthalate as a main repeating unit, and the middle layer is made of toxylylene diamine or a mixture of toxylylene diamine and p-xylylene diamine as a diamine component. It is made of polyamide with
A multilayer container is disclosed in which the thinned portion is oriented in at least one direction. The publication states that the container has excellent oxygen barrier properties without impairing the excellent mechanical properties, transparency, chemical resistance, etc. of polyester.

Furthermore, JP-A-58-183243 discloses a biaxially stretched blow-molded bottle body in which two inner and outer surface layers are made of polyethylene terephthalate and an intermediate layer is made of a mixed material of polyethylene terephthalate and xylylene group-containing polyamide. Disclosed.

Furthermore, JP-A-56-100828 discloses that linear hydroquinone phenoxy polymers prepared from hydroquinone and epihalohydrin are characterized by low permeability to oxygen and carbon dioxide.

Additionally, the Journal of Applied Polymer Science
lymerScience) Volume 7 2135-214
4 (1963) has the following formula: + 0- E -0-CH2-CI-CH2+...(
2) The gas barrier properties of a homopolyhydroxy ether represented by: 1'H are disclosed. The one with the lowest oxygen permeability is E
is later, and its value is 0.5cc-ail/10
0in2/24hr/atm. The lowest water vapor mobility is E is CH3, and its value is 100°F190%R,11,
3g-wit/login 24h under conditions of
It is r.

The Journal of Applied Polymers and Science
ymerScience) Volume 7 2145-2152
(1963) discloses the gas barrier properties of a copolyhydroxypolyether represented by the following formula ()...■) where R1 is, however, R1 and R2 are not the same. The one with the lowest oxygen permeability is the one where R is CH3 H3, and the value in both cases is 5 g-xl/10
0 in"/24 hr/atl+. The lowest water vapor transfer layer is one in which R1 is CH7 CH, Br CH3, both of which are 4 g ・if/100 in2/24 hr under the condition of 100°F and 190% RH. It is.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a polyester composition containing a novel co-condensed polyester.

Another object of the present invention is to provide a polyester composition comprising polyhydroxy polyether and polyalkylene terephthalate whose main constituents are ethylene terephthalate and which have excellent gas barrier properties, especially barrier properties against oxygen and carbon dioxide gas.

Still another object of the present invention is to provide a polyester composition that not only has excellent gas barrier properties but also excellent melt moldability and stretchability.

Still another object of the present invention is to provide a stretched molded article, a preform for a stretched hollow molded article, and a stretched hollow molded article made of the polyester composition of the present invention.

Further objects and advantages of the present invention will become apparent from the description below.

According to the present invention, the objects and advantages of the present invention are, firstly, polyalkylene terephthalate (A) having ethylene terephthalate as a main constituent unit and co-condensed polyester (
A polyester composition consisting of B), wherein the co-condensed polyester (B) contains (al) 25 to 48 mol% of aromatic dicarboxylic acid component units whose main component is isophthalic acid component units; (c) 2 to 25 mol% of aromatic oxycarboxylic acid component units having 12 or less carbon atoms, and (d) 3 carbon atoms. and (e) 0.5 to 1.5 d1/g of polyfunctional compound component units having 3 or more carboxyl or hydroxyl groups in the range of 0 to 15 mol %, and (e) 0.5 to 1.5 d1/g. Niall intrinsic viscosity [
[eta]] and (f) a glass transition temperature in the range from 50 to 120[deg.]C.

The co-condensed polyester of the present invention has aromatic dicarboxylic acid component units (al,
A diol component unit (bl) whose main component is an ethylene glycol component unit, an aromatic oxycarboxylic acid component unit (c
It can be a ternary co-condensed polyester consisting of 1, and an aromatic dicarboxylic acid component unit having an isophthalic acid component unit as a main component (Al, a diol component unit having an ethylene glycol component unit as a main component) , a quaternary co-condensed polyester comprising an aromatic oxycarboxylic acid component unit (c) and a polyfunctional compound component unit (d). In either case, in the co-condensed polyester of the present invention, adjacent carboxyl groups and hydroxyl groups of each component unit are condensed to form an ester bond, and adjacent phenolic hydroxyl groups and hydroxyl groups of the diol component unit are condensed. A polymer molecular chain is formed by condensing and forming an ether bond. Any of the above component units may be placed at the molecular end of the co-condensed polyester, and the carboxyl group present at the molecular end may be esterified with another lower alcohol; The hydroxyl groups present may be esterified with other lower carboxylic acids or etherified with other alcohols, and diol component units (based on ethylene glycol component units constituting the co-condensed polyester) In b), a small portion (for example, 10 mol % or less) may form a diol component unit having an ether bond through a reaction between diol component units such as diethylene glycol component units.

The co-condensed polyester of the present invention has a substantially linear structure. Here, the term "substantially linear structure" means that it consists essentially of a linear structure or a chain structure having a branched chain, and it means that it is not substantially a gel-like crosslinked structure (network structure). This is confirmed by the fact that the co-condensed polyester of the present invention is substantially completely dissolved in the phenol-tetrachloroethane mixed solvent (weight ratio 1/1). When the co-condensed polyester is a co-condensed polyester consisting of the above-mentioned three components, it is a straight chain polyester, and when it is a co-condensed polyester consisting of the above-mentioned picture-constituting components, it is a branched polyester.

The composition of the co-condensed polyester of the present invention is (al) the aromatic dicarboxylic acid component unit having isophthalic acid component unit as the main component is in the range of 25 to 48 mol%, preferably 30 to 48 mol%, ethylene Diol component units mainly composed of glycol component units are in the range of 45 to 50 mol%, preferably 46 to 50 mol%, and (c) aromatic oxycarboxylic acid component units are in the range of 2 to 25 mol%, preferably and (d) O to 2 mol% of polyfunctional compound component units having a carbon atom number in the range of 3 to 15 and having 3 or more carboxyl groups or hydroxyl groups; The composition is preferably in the range of 0 to 1.5 mol%. In the co-condensed polyester, the content of the aromatic dicarboxylic acid component unit (a) is less than 25 mol% and the aromatic oxycarboxylic acid component unit (c1
If the content of
Moreover, the gas barrier properties of the co-condensed polyester and its stretched product are reduced, which is unfavorable from the viewpoint of productivity and performance.

Further, in the co-condensed polyester, the content of aromatic dicarboxylic acid component units (a) is greater than 48 mol% and the content of aromatic oxycarboxylic acid component units (c) is less than 2 mol%. Those with the composition have already been used in the Journa during the polycondensation reaction during the production of the polyester.
As reported in Polymer 5science, Vol. 40 (1955), p. 59, a cyclic oligomer of isophthalic acid and ethylene glycol is produced, and the production of the cyclic oligomer reduces the polymer yield. This is unfavorable in terms of productivity, since the oligomers precipitate and stick to the unheated parts of the polymerization apparatus. Furthermore, since the oligomer is likely to be mixed in when recovering the co-condensed polyester after the polycondensation reaction, there is a possibility that quality problems may occur, and special measures must be taken to avoid this problem. In addition, if the content of the polyfunctional compound units constituting the co-condensed polyester is greater than 2 mol%, the co-condensed polyester tends to contain a large amount of gel-like structure. As a result, it is no longer substantially linear, and its melt moldability is reduced.

The co-condensed polyester of the present invention has an intrinsic viscosity of 2 in a mixed solvent of phenol and tetrachloroethane (weight ratio 1/1).
value measured at 5°C] is required to be in the range of 0.5 to 1.5 dl/g. Within this range, it is preferably in the range of 0.6 to 12 dl/g. Further, it is necessary that its glass transition point is in the range of 50 to 120°C. Within this range, the temperature is preferably in the range of 55 to 100°C.

The intrinsic viscosity of the co-condensed polyesteramide is 1.5 di/
When it is larger than g, the melt moldability of the co-condensed polyester decreases, and furthermore, its stretchability also decreases, and when it is smaller than 0.5 d1/g, the mechanical strength of the co-condensed polyester and its stretched product decreases. I come to do it. Further, if the glass transition temperature of the co-condensed polyester is lower than 50°C, it is not preferable because it becomes difficult to economically carry out the drying necessary to reduce the molecular weight reduction during melt molding of the polyester.

The aromatic dicarboxylic acid component unit (a) constituting the co-condensed polyester of the present invention has isophthalic acid component units as a main component, and the ratio of isophthalic acid component units to all aromatic dicarboxylic acid component units is is usually 50 to 100 mol%, preferably 70 to 100 mol%
is within the range of Examples of aromatic dicarboxylic acid component units other than isophthalic acid component units include terephthalic acid,
Examples include aromatic dicarboxylic acid component units having 8 to 12 carbon atoms such as phthalic acid and 2',6-naphthalene dicarboxylic acid.

The diol component unit (b) constituting the co-condensed polyester of the present invention is mainly composed of ethylene glycol component units, and the ratio of the ethylene glycol component units to the total diol component units is usually 50 to 100 mol%, preferably ranges from 70 to 100 mol%.

Diol component units other than ethylene glycol include:
For example, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, cyclohexanediol, cyclohexane dimetatool, 1,4-bis(
β-hydroxyethoxy)benzene, 1,3-bis(β
-hydroxyethoxy)benzene, 2,2-bis(4-
β-hydroxyethoxyphenyl)propane, bis(4
-β-hydroxyethoxyphenyl) sulfone and the like can be exemplified by diol component units having 3 to 15 carbon atoms.

The aromatic oxycarboxylic acid component unit (c) constituting the co-condensed polyester of the present invention has 7 to 1 carbon atoms.
This is an aromatic oxycarboxylic acid component unit within the range of 2. More specifically, salicylic acid, 4-methylsalicylic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 3-methyl-4-hydroxybenzoic acid, 4-hydroxy-1-naphetic acid, 6-methyl-4- Hydroxy-
Examples include 1-naphetic acid, and these 2
It may be a mixture of more than one species.

The polyfunctional compound component unit (cd) constituting the co-condensed polyester of the present invention is a trifunctional or higher polyfunctional compound having three or more carboxyl groups or hydroxyl groups having a carbon atom number in the range of 3 to 15. component unit,
It also includes polyfunctional compound component units having three or more carboxyl groups and hydroxyl groups in total. Specifically, the polyfunctional compound component unit includes aromatic polybasic acids such as trimellitic acid, trimesic acid, 3.3', 5.5'-tetracarboxydiphenyl, and aliphatic acids such as butanetetracarboxylic acid. Polybasic acid, phloroglucin, 1
．． Examples include aromatic polyols such as 2.4.5-tetrahydroxybenzene, aliphatic polyols such as glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol, and oxypolycarboxylic acids such as tartaric acid and malic acid. I can do it.

The co-condensed polyester of the present invention can be produced according to the conventionally known polycondensation method employed in the production of polyethylene terephthalate.

The aromatic dicarboxylic acid component unit as a component may be, for example, the aromatic dicarboxylic acid, its dialkyl ester, or the bis β of the aromatic Cica JLt fonic acid.
- Can be formed by feeding into the reaction system as an ester of a diol, such as hydroxyethyl ester.

Further, the diol component unit as a component can be formed by supplying it to the reaction system, for example, as a diol or in the form of a diol ester of a carboxylic acid as a component.

Further, the aromatic oxycarboxylic acid component unit of the constituent component may be, for example, as the aromatic oxycarboxylic acid, as an alkyl ester of the aromatic oxycarboxylic acid, or as an ether of an aromatic oxycarboxylic acid with a diol. Furthermore, it can be supplied to the reaction system as a diol ester of the aromatic oxycarboxylic acid.

As the catalyst for copolycondensation, for example, a catalyst consisting of antimony, germanium, titanium, or a compound thereof and a phosphorus compound is used. As the form of the antimony, germanium or titanium compound, oxides, hydroxides, halides, inorganic acid salts, organic acid salts, complex salts, double salts, alcoholades, phenolates and the like are used. These catalysts can be used alone or as a mixture of two or more. The proportion of metals or their compounds used in these catalysts is
The atomic ratio of antimony, germanium or titanium to a total of 1 mole of non-number dicarboxylic acid and aromatic oxycarboxylic acid is usually 10-3 to 10.
Gram atoms, preferably 5x10- to 5x10'
This is the range of Durham atoms. Phosphorus compounds are used in the form of phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, various esters thereof, phosphines, phosphites, and the like. The proportion of the phosphorus compound to be used is usually 10 to 10, preferably 2 as the atomic ratio of phosphorus to 1 mole of aromatic dicarboxylic acid and aromatic oxycarboxylic acid.
It ranges from X10' to 5X10-' gram atoms.

These catalysts can be supplied to the polycondensation system from the initial stage of the etherification reaction, esterification reaction or transesterification reaction, or they can be supplied to the reaction system before proceeding to the polycondensation reaction stage. It can also be supplied to the reaction system.

In addition, during co-condensation, catalysts for transesterification used in the production of polyethylene terephthalate, diethylene glycol production inhibitors, heat stabilizers, light stabilizers, lubricants,
Various additives such as pigments and dyes can be used.

As catalysts for these transesterification reactions, metal compounds such as calcium, magnesium 1, lithium, zinc, cobalt, and manganese can be used. The forms of these compounds include oxides, hydroxides, halides,
Inorganic acid salts, organic acid salts, etc. are used. As the diethylene glycol production inhibitor, amines such as triethylamine and tri-n-butylamine, and quaternary ammonium compounds such as tetraethylammonium hydroxide and tetrabutylammonium hydroxide can be used. Further, as a stabilizer such as a heat stabilizer, a phosphorus compound such as phosphoric acid, phosphorous acid, hypophosphorous acid, or an ester thereof can be used.

The co-condensed polyester of the present invention is produced by a conventionally known melt polycondensation method, and in some cases by employing a solid phase polycondensation method after the melt polycondensation method. In such a melt polycondensation method, a so-called direct polymerization phase method can be employed, or a so-called transesterification polycondensation method can also be employed. The melt polycondensation method uses, for example, isophthalic acid or an aromatic dicarboxylic acid whose main component is isophthalic acid or an ester derivative thereof, ethylene glycol or a diol whose main component is isophthalic acid, an aromatic oxycarboxylic acid, or its dicarboxylic acid. The condensate, and optionally a polyfunctional compound containing three or more carboxyl groups or hydroxyl groups, are esterified and etherified or transesterified simultaneously or sequentially preferably at a temperature of 100 to 280°C. This can be carried out by forming an initial polycondensate and then polycondensing it at a temperature above its melting point, preferably 200 to 300° C., under vacuum or under an inert gas flow without stirring.

Further, the co-condensed polyester of the present invention can be produced by further subjecting the polyester obtained by the melt polycondensation method to solid phase polycondensation to increase the molecular weight. The solid phase polycondensation method is, for example, a method in which a polyester obtained by a melt polycondensation method is made into fine particles and held at a temperature below the melting point, preferably 180 to 240°C, under vacuum or under an inert gas flow. It can be implemented.

The other polyalkylene terephthalate (A) constituting the polyester composition of the present invention is a polyester having ethylene terephthalate as a main constituent unit. The content of ethylene terephthalate structural units in the polyalkylene terephthalate is usually 50 mol% or more, preferably 70 mol% or more. The dicarboxylic acid component units constituting the polyalkylene terephthalate may contain a small amount of other aromatic dicarboxylic acid component units in addition to the terephthalic acid component units. Specific examples of aromatic dicarboxylic acid component units other than terephthalic acid component units include isophthalic acid, phthalic acid, and naphthalene dicarboxylic acid. The diol component units constituting the polyalkylene terephthalate may contain small amounts of other diol component units in addition to ethylene glycol component units.

Specifically, other diol component units other than ethylene glycol component units include 1,3-propanediol, 1,
4-butanediol, neopentyl glycol, cyclohexanediol, cyclohexane dimetatool, 1,
4-bis(β-hydroxyethoxy)benzene, 1,3
-bis(β-hydroxyethoxy)benzene, 2,2-
Examples include diol component units having 3 to 15 carbon atoms such as bis(4-β-hydroxyethoxyphenyl)propane and bis(4-β-hydroxyethoxyphenyl)sulfone.

In addition to the aromatic dicarboxylic acid component unit and the diol component unit, the polyalkylene terephthalate may contain a small amount of a polyfunctional compound as required. Specifically, the polyfunctional compound component units include trimellitic acid, trimesic acid, 3,3'',
Aromatic polybasic acids such as 5,5''-tetracarboxydiphenyl, aliphatic polybasic acids such as butanetetracarboxylic acid, phloroglucin, aromatic polyols such as 1.2.4.5-tetrahydroxybenzene, glycerin,
Aliphatic polyols such as trimethylolethane, trimethylolpropane, and pentaerythritol, tartaric acid,
Examples include oxypolycarboxylic acids such as malic acid.

The composition of the constituent components of the polyalkylene terephthalate is:
The content of terephthalic acid component units is usually 50 to 100.
The content of aromatic dicarboxylic acid component units other than terephthalic acid component units is usually in the range of 0 to 50 mol%, preferably 0 to 30 mol%. , the content of ethylene glycol component units is usually in the range of 50 to 100 mol%, preferably 70 to 100 mol%, and the content of diol component units other than the ethylene glycol component units is usually O to 50 mol%, Preferably, the content is in the range of O to 30 mol % and the content of polyfunctional compound component units is usually in the range of 0 to 2 mol %, preferably in the range of O to 1 mol %. Further, the intrinsic viscosity [η] of the polyalkylene terephthalate (value measured at 25°C in a mixed solvent of phenol and tetrachloroethane (weight ratio 1/1)) is usually 0.5 to 1.5 dl/g, preferably The melting point is usually in the range of 210 to 265°C, preferably 220 to 260°C, and the glass transition temperature is usually in the range of 50 to 120°C, preferably 60 to 100°C. range.

In the polyester composition of the present invention, the proportion of the co-condensed polyester (B) is usually 2 to 50 parts by weight per 100 parts by weight of the polyalkylene terephthalate (A).
0 parts by weight, preferably 3 to 300 parts by weight, particularly preferably 5 to 100 parts by weight.

The polyester composition of the present invention includes the polyalkylene terephthalate (A) and the co-condensed polyester (
In addition to B), conventionally known nucleating agents, inorganic fillers,
Appropriate amounts of various additives such as lubricants, slip agents, antiblocking agents, stabilizers, antistatic agents, antifogging agents, and pigments may be blended.

The polyester composition of the present invention can be used in an unstretched state as a raw material for films, sheets, fibers, containers, and other molded bodies of various shapes by ordinary molding methods.

Furthermore, by molding the polyester composition in a stretched state into a film, sheet, or container, a molded product with even better gas barrier properties can be obtained. Next, a stretched molded product of the polyester composition of the present invention will be explained.

The stretched products of the polyester composition of the present invention include -axially stretched products and two-wheel stretched products, and the form thereof may be a film, sheet, or fiber. When uniaxially stretched, the stretching ratio is usually 1.1 to 10 times, preferably 1.2 to 8 times, particularly preferably 1.5 to 7 times. When the stretched product is biaxially stretched, the stretching ratio in the longitudinal direction is usually 1.1 to 8 times, preferably 1.2 to 7 times, and particularly preferably 1.5 to 8 times. 6 times the range, and typically 1 in the horizontal axis direction.
．． The stretched product can be heat-cerated depending on the purpose of use. .

Any conventionally known method can be employed as a method for producing a stretched product of the polyester composition of the present invention. In general, an original molded product such as a film or sheet formed from the polyester composition or a composition further containing the additives as necessary is used as it is or once cooled to a temperature below the glass transition point. After solidification, the original molded product is reheated and then stretched at a temperature ranging from the glass transition temperature to the melting point, preferably from the glass transition temperature to a temperature 80° C. higher than the glass transition point. In order to heat set the stretched product, an appropriate short-time heat treatment is performed at the stretching temperature or a higher temperature.

In the method for producing a stretched molded product of the polyester composition of the present invention, when the original molded product is a film-like product (sheet-like product), an unstretched film-like product (sheet-like product) is stretched in the -axial direction. (-axial stretching), a method of stretching in the vertical axis direction and then further stretching in the horizontal axis direction (biaxial stretching), a method of simultaneously stretching in the vertical axis direction and the horizontal axis direction (biaxial stretching),
A method of repeating sequential stretching in any one direction after two-wheel stretching, a method of further stretching in both directions after two-wheel stretching, and reducing the pressure in the space between the film-like material (sheet-like material) and the mold. For example, the so-called vacuum forming method in which stretch molding is carried out by stretching can be exemplified.It is also possible to produce these stretch molded polyester compositions in the form of a laminate with other resins. As such a manufacturing method, an original molded product such as a film-like product (sheet-like product) of the polyester composition is mixed with an original molded product such as a film-like product (sheet-like product) of another resin, respectively in a single layer or in a double layer. Examples include a method in which layers are laminated and then stretched, or a method in which a film-like material (sheet-like material) of another resin is adhered to a stretched product of the polyester composition.

The stretched molded product of the polyester composition of the present invention has excellent properties such as mechanical strength and gas barrier properties.
It can be used for various purposes such as films, sheets, tubular bodies, containers, and bottles.

The polyester stretched hollow molded preform of the present invention is formed from the polyester composition,
It is molded by a conventionally known method. For example, the preform for a polyester hollow molded body of the present invention can be obtained by molding a tubular object made of the polyester composition.

The polyester stretched hollow molded body of the present invention is a stretched hollow molded body formed from the polyester composition, and is produced by stretch blow molding the preform for the stretched hollow molded body. The stretched hollow molded product may be a uniaxially stretched product or a two-wheel stretched product,
Generally, biaxially oriented materials have good mechanical strength and gas barrier properties.
It is suitable because it has excellent properties. As for the stretching ratio of the stretched hollow molded article, the stretching ratio described for the stretched molded article of the polyester composition can be used as is.

The polyester stretch hollow molded article of the present invention is produced by stretch-blow molding the preform for the polyester hollow molded article. Examples of this method include a method (biaxial stretch blow molding) in which a preform at the above temperature is stretched in the vertical axis direction and then further blow molded to stretch it in the horizontal axis direction.

The polyester stretched hollow molded article of the present invention has mechanical strength,
Since it has excellent heat resistance and gas barrier properties, it can be used for various purposes. (In addition, since the two-wheeled stretch-blow molded container of the present invention has excellent gas barrier properties,
It is excellent as a container for seasonings, oil, alcoholic beverages such as beer and sake, soft drinks such as cola, Saigu, and juice, cosmetics, detergents, etc., but especially when used as a container for beer or carbonated drinks, the wall thickness of the container can be thinned. It also becomes possible to extend the best-before period.

Next, the present invention will be specifically explained using examples. In addition, in Examples and Comparative Examples, performance evaluation was performed according to the following method.

Intrinsic viscosity of polyalkylene terephthalate (A) [η]
And the intrinsic viscosity [η] of the co-condensed polyester (B) is
Phenol-tetrachloroethane mixed solvent (weight ratio 10
0:100) at 25°C.

The glass transition temperature of the polyalkylene terephthalate (A) and the co-condensed polyester (B) was measured using a differential scanning calorimeter of a resin sample obtained by heating it to a molten fluid state and rapidly cooling it to room temperature at 10°C/ff1in. It was determined by measuring at a heating rate of .

Regarding the gas barrier properties of sheet-like or film-like products of polyester compositions, stretched polyester composition products, and stretched hollow molded products of polyester compositions,
The oxygen gas permeability coefficient was measured using an Oxytrough (OXTRAN) device manufactured by MOCON, and the carbon dioxide gas permeability coefficient was measured using a Permatran (PE) device manufactured by MOCON.
RMATRAM) 25 each using C-■ equipment.
Measured at °C.

〔Example〕

Example 1 Polyethylene terephthalate (trade name, Sankata PET J 135) dried at 150°C for 10 hours 100
Isophthalic acid/p-hydroxybenzoic acid/ethylene glycol co-condensed polyester [composition (mole ratio) near: 48], which was dried under reduced pressure at 55°C for 12 hours based on the weight part
, intrinsic viscosity [η) 0.76 dl/g, glass transition temperature (Tg) 65°C], 40 parts by weight were mixed, and this mixture was melt-extruded using an extruder at a molding temperature of 270°C, and after cooling, it was cut to form polyethylene. Pellets of a composition of terephthalate and co-condensed polyester were produced. Further, press molding was performed using this press sheet to produce a press sheet having a thickness of about 100 μm. The obtained press sheet was colorless and transparent, and as a result of gas barrier property measurement, the carbon dioxide gas permeability coefficient was 8.9 f·ml.
rd -day -atm sThe oxygen gas permeability coefficient is 1.8 ml・tm/rd・day・at
It was m.

Examples 2 to 4 A press sheet having a thickness of about 100 μm was produced in the same manner as in Example 1, except that the co-condensed polyester in Example 1 was used for the polyethylene terephthalate shown in Table 1 as shown in Table 1. The carbon dioxide permeability coefficient of the obtained press sheet was as shown in Table 1.

Comparative Example 1 Using the polyethylene terephthalate in Example 1, a press sheet having a thickness of about 100 μm was produced in the same manner as in Example 1. The carbon dioxide gas permeability coefficient of which press sheet is 25mZ −+n / rd −day ・at
+nAlso, the oxygen gas permeability coefficient is 4.5m1-van/
It was rd-day atm.

゛ Example 5 to Step 0 The same procedure as in Example 1 was carried out, except that the co-condensed polyester or polyethylene terephthalate listed in Table 2 was used instead of the co-condensed polyester or polyethylene terephthalate in Example 1, respectively, as shown in Table 2. A 100 μm press sheet was produced. The carbon dioxide gas permeability coefficient of the obtained press sheet was as shown in Table 2.

Example 11 The mixture of polyethylene terephthalate and co-condensed polyester in Example 1 was molded using an extruder at a temperature of about 2
It was melted at 70° C., fed into a single-phase coat hanger type T-die and extruded into a sheet, and further cooled to produce an extruded sheet with a thickness of about 100 μm. The obtained sheet is colorless and transparent, and its oxygen gas permeability is 1.6i+
l-tml rd -day"air', and the carbon dioxide permeability coefficient is 8.8i+j-tml rrlday"
It was Iatm.

Example 12 A two-wheel stretched film was produced by simultaneously stretching the press sheet in Example 1 three times in the vertical axis direction and the horizontal axis direction using a two-wheel stretching device.

The obtained biaxially stretched film had a thickness of about 11 μm, and had little thickness unevenness (it was stretched uniformly). The carbon gas permeability coefficient of this stretched film was 7.1 ml·M.
/rd-day-at++.

Examples 13 to 22 Stretched films were prepared by carrying out simultaneous two-wheel stretching at the magnification shown in Table 3 in the same manner as in Example 12, except that the press sheets or extruded sheets shown in Table 3 were used instead of the press sheets in Example 12. did.

The obtained stretched films each had the average thickness shown in Table 3, and all were uniformly stretched.

Furthermore, the carbon dioxide gas permeability coefficients of these biaxially stretched films are as shown in Table 3. Comparative Example 2 The press sheet of polyethylene terephthalate in Comparative Example 1 was heated in the same manner as in Example 12 in the vertical and horizontal directions. A two-wheel stretched film was produced by simultaneously stretching the film.

This two-wheel stretched film has a thickness of about 11μ, and its carbon dioxide permeability coefficient is 16m1-w/rd-day.
-It was an ATM.

Example 23 The mixture of polyethylene terephthalate and co-condensed polyester in Example 1 was injection molded using an injection molding machine at a molding temperature of about 270° C. to produce a preform (cold parison) with a thickness of 3.21III+. Then,
Approximately 2.5 times the length and approximately 4 times the width using a biaxial stretch blow molding machine
A stretched bottle with an internal volume of about 11 times was formed by biaxial stretching. The carbon dioxide permeability of this stretched bottle is 2.1 mZ/d
It was ay-bottle-atm.

Comparative Example 3 Polyethylene terephthalate in Example 1 was injection molded to have the same thickness as the preform in Example 23 (approximately 3.2
A preform consisting only of a polyethylene terephthalate layer with m was prepared. Next, this preform was stretch-blown in the same manner as in Example 23, so that the minimum wall thickness was approximately 300 mm.
A stretched bottle with an inner volume of about 11 μm and an inner volume of about 11 was produced. Furthermore, as a result of measuring the carbon dioxide gas permeability coefficient of this stretched bottle,
4.0 ml・vm/nf-day-atll
Met.

Example 24 The same procedure as in Example 23 was carried out except that the mixture of polyethylene terephthalate and co-condensed polyester in Example 7 was used instead of the mixture of polyethylene terephthalate and co-condensed polyester in Example 23. An axially stretched bottle was produced. The carbon dioxide permeability of this stretched bottle is 2.2 mZ/day -bottle
-It was an ATM.

〔Effect of the invention〕

The polyester composition of the present invention has excellent melt moldability, stretch moldability, and gas barrier properties, and is excellent as a material for stretched molded bodies, stretched hollow molded body preforms, and stretched hollow molded bodies.

(1 other person)

Claims (4)

[Claims] (1) A polyester composition consisting of a polyalkylene terephthalate (A) containing ethylene terephthalate as a main constituent unit and a co-condensed polyester (B), wherein the co-condensed polyester (B) contains (a) isophthalic acid component units. 25 to 48 mol% of aromatic dicarboxylic acid component units as the main component; (b) 45 to 50 mol% of diol component units mainly composed of ethylene glycol component units; (c) the number of carbon atoms is 12 or less. Aromatic oxycarboxylic acid component unit is 2
and (d) 0 to 2 mol% of polyfunctional compound component units having a carbon number in the range of 3 to 15 and having 3 or more carboxyl groups or hydroxyl groups, and (e) Intrinsic viscosity in the range of 0.5 to 1.5 dl/g [
η] and (f) a glass transition temperature in the range of 50 to 120°C. (2) A stretched molded article of a polyester composition consisting of a polyalkylene terephthalate (A) whose main constituent unit is ethylene terephthalate and a co-condensed polyester (B), wherein the co-condensed polyester (B) comprises (a) isophthalate; 25 to 48 mol% of aromatic dicarboxylic acid component units mainly composed of acid component units, (b) 45 to 50 mol% of diol component units mainly composed of ethylene glycol component units, (c) number of carbon atoms. is 12 or less aromatic oxycarboxylic acid component unit is 2
and (d) 0 to 2 mol% of polyfunctional compound component units having a carbon number in the range of 3 to 15 and having 3 or more carboxyl groups or hydroxyl groups, and (e) Intrinsic viscosity in the range of 0.5 to 1.5 dl/g [
η] and (f) a glass transition temperature in the range of 50 to 120°C. (3) A preform for a polyester stretched hollow molded body formed from a polyester composition consisting of a polyalkylene terephthalate (A) whose main constituent unit is ethylene terephthalate and a co-condensed polyester (B),
The co-condensed polyester (B) contains (a) 25 to 48 mol% of aromatic dicarboxylic acid component units whose main component is isophthalic acid component units, and (b) diol component units whose main component is ethylene glycol component units. (c) 2 aromatic oxycarboxylic acid component units having 12 or less carbon atoms;
and (d) 0 to 2 mol% of polyfunctional compound component units having a carbon number in the range of 3 to 15 and having 3 or more carboxyl groups or hydroxyl groups, and (e) Intrinsic viscosity in the range of 0.5 to 1.5 dl/g [
η] and (f) a glass transition temperature in the range of 50 to 120°C. (4) A polyester stretched hollow molded article formed from a polyester composition consisting of a polyalkylene terephthalate (A) whose main constituent unit is ethylene terephthalate and a co-condensed polyester (B), wherein the co-condensed polyester (B) , (a) 25 to 48 mol% of aromatic dicarboxylic acid component units whose main component is isophthalic acid component units, (b) 45 to 50 mol% of diol component units whose main component is ethylene glycol component units, ( c) 2 aromatic oxycarboxylic acid component units having 12 or less carbon atoms
and (d) 0 to 2 mol% of polyfunctional compound component units having a carbon number in the range of 3 to 15 and having 3 or more carboxyl groups or hydroxyl groups, and (e) Intrinsic viscosity in the range of 0.5 to 1.5 dl/g [
η] and (f) a glass transition temperature in the range of 50 to 120°C.