JPH02269117A - Co-condensed polyester, production and use thereof - Google Patents

Abstract

PURPOSE:To obtain the title polymer useful as a material for gas barrier containers, having excellent melting and molding properties, drawing properties, mechanical properties, etc., by copolymerizing specific amounts of isophthalic acid with naphthalenedicarboxylic acid, etc., ethylene glycol and polyfunctional compound. CONSTITUTION:(A) 2.5-42mol% mononuclear aromatic dicarboxylic acid consisting essentially of isophthalic acid is polymerized with (B) 8-25mol% binuclear aromatic dicarboxylic acid consisting essentially of 2,6- naphthalenedicarboxylic acid, (C) 48-50mol% diol consisting essentially of ethylene glycol and (D) 0-2mol% 3-15C polyfunctional compound containing three or more carboxyl groups and/or hydroxyl groups, for example, by melt polymerization, to give the aimed polymer having 0.5-1.5dl/g intrinsic viscosity and >=70 deg.C glass transition temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a co-condensed polyester having excellent melt moldability, stretchability, mechanical strength, transparency and gas barrier properties, and having performance suitable as a material for containers, etc. The present invention relates to a method for producing this co-condensed polyester and a gas barrier property imparting agent using this co-condensed polyester.

Technical background of the invention and its problems Glass has been widely used as a container material for seasonings, oils, beer, alcoholic beverages such as Japanese sake, soft drinks such as carbonated drinks, cosmetics, detergents, and the like. 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.

Moreover, glass containers are heavy, which increases shipping costs, and they also have drawbacks such as being easily damaged and inconvenient to handle.

In view of the above-mentioned drawbacks of glass containers, various plastic containers are increasingly being used in place of glass containers. Such plastic containers are manufactured using various plastics depending on the type of material to be filled in the container and the purpose of use.

Among the materials that form such plastic containers,
Polyethylene terephthalate has excellent gas barrier properties and transparency, and is used as a material for containers for seasonings, soft drinks, detergents, cosmetics, etc.

However, among these containers, containers for beverages such as beer and carbonated beverages, which are filled with carbon dioxide gas, require extremely high gas barrier properties compared to other uses. Therefore, even polyethylene terephthalate, which has relatively high pass barrier properties, is still not sufficient as a material for forming such containers.

Under these circumstances, when manufacturing these containers, the necessary gas barrier properties are ensured by increasing the thickness of the polyethylene terephthalate.

It has also been proposed to improve the gas barrier properties of polyethylene terephthalate by cocondensing a third component during the production of polyethylene terephthalate as described above. For example, as a method for improving the gas barrier properties of such polyethylene terephthalate, a method of cocondensation polymerization of aromatic oxycarboxylic acid component units is known when producing polyethylene terephthalate. By co-condensing the third component in this way, the gas barrier properties of polyethylene terephthalate are improved to some extent, and properties such as stretchability are also improved to a certain extent.

However, the gas barrier property has not been improved to the extent that it is suitable for filling sparkling beverages such as beer or carbonated drinks. Therefore, when using polyethylene terephthalate containers as containers for sparkling beverages, etc., methods such as increasing the wall thickness have to be adopted, and in this respect, there is room for improvement in resin containers.

OBJECTS OF THE INVENTION The first object of the present invention is to provide a co-condensed polyester that has excellent gas barrier properties, particularly against gases such as oxygen and carbon dioxide, and also has excellent mechanical strength.

A second object of the present invention is to provide a co-condensed polyester with excellent melt moldability and stretchability.

A third object of the present invention is to provide a co-condensed polyester that can impart excellent gas barrier properties to polyalkylene terephthalate, particularly polyethylene terephthalate.

A fourth object of the present invention is to provide a method for producing a co-condensed polyester having excellent gas barrier properties, particularly gas barrier properties against oxygen and carbon dioxide.

A fifth object of the present invention is to provide a method for producing a co-condensed polyester having excellent melt moldability and stretchability.

A sixth object of the present invention is to produce a molded article that has excellent moldability, gas barrier properties, and food safety, and also has excellent gas barrier properties by blending it with polyalkylene terephthalate, particularly polyethylene terephthalate. An object of the present invention is to provide a method for producing a co-condensed polyester that can form a composition that can be used.

Furthermore, a seventh object of the present invention is to provide a gas barrier that can improve the gas barrier properties of polyalkylene terephthalate by blending it with polyalkylene terephthalate or by forming a laminate with polyalkylene terephthalate. The purpose is to provide sex-enhancing agents.

Summary of the Invention The co-condensed polyester according to the present invention comprises (mononuclear aromatic dicarboxylic acid component units whose main component units are di-isophthalic acid component units; 25 to 42 mol%), (b12,6-naphthalene dicarboxylic acid component) Dinuclear aromatic dicarboxylic acid component unit whose main component unit is a unit;
8 to 25 mol%, (c) diol component units whose main component units are ethylene glycol component units; 48 to 50 mol%, and (d) having a total of 3 or more carboxyl groups and/or hydroxyl groups. , and a polyfunctional component unit derived from a polyfunctional compound having a carbon atom number in the range of 3 to 15; 0 to 2 mol, (however, the total of a, b, c and d component units is 100
is a substantially linear co-condensed polyester composed of
41/g and the glass transition temperature is 70°C
It is characterized by the above.

Further, in the method for producing the co-condensed polyester according to the present invention, the content of the mononuclear aromatic dicarboxylic acid component unit (a) is 25 to 25%.
42 mol%, dinuclear aromatic dicarboxylic acid component unit (b)
The content of diol component units (c) is 48 to 50 mol%, and the content of polyfunctional component units (d) is 8 to 25 mol%.
) whose main component is (1') isophthalic acid or its ester, so that the content of Mononuclear aromatic dicarboxylic acid component, (b')2.6-
A dinuclear aromatic dicarboxylic acid component whose main component is naphthalene dicarboxylic acid or its ester, (c') a diol component whose main component is ethylene glycol, and (d') three or more carboxyl groups and/or hydroxyl groups. A mixture prepared by blending a polyfunctional component consisting of a polyfunctional compound or an ester thereof having a carbon atom number in the range of 3 to 15 is heated to perform an esterification reaction or transesterification reaction with the above component. After that, a copolycondensation reaction is carried out at a temperature within the range of 230 to 300°C in the presence of a catalyst consisting of a compound selected from the group consisting of germanium compounds, antimony compounds and titanium compounds and a phosphorus compound. There is.

Furthermore, the gas barrier property imparting agent according to the present invention includes (1)
Mononuclear aromatic dicarboxylic acid component unit whose main component unit is isophthalic acid component unit; 25 to 42 mol%, (b) Dinuclear aromatic system whose main component unit is 2,6-naphthalene dicarboxylic acid component unit dicarboxylic acid component unit;
8 to 25 mol%, (c) diol component units whose main component units are ethylene glycol component units; 48 to 50 mol%, and (d) having a total of 3 or more carboxyl groups and/or hydroxyl groups. , and a polyfunctional component unit derived from a polyfunctional compound having a carbon atom number in the range of 3 to 15; 0 to 2 mol% (however, the total of a, b, c and d component units is 100
mol%), is substantially linear, has an intrinsic viscosity [η] in the range of 0.6 to 1.6 dl/g, and has a glass transition temperature of 70°C or higher. It is characterized by containing condensed polyester.

The co-condensed polyester according to the present invention differs from conventionally widely used polyethylene terephthalate and the like in that the co-condensed polyester has a mononuclear aromatic dicarboxylic acid component unit whose main component unit is an isophthalic acid component unit as a dicarboxylic component unit, and a 2.6- Since the naphthalene dicarboxylic acid component unit is the main component unit, it has particularly excellent gas barrier properties and also has excellent properties such as melt moldability, mechanical strength, and stretchability.

When such a co-condensed polyester is used particularly with a thermoplastic such as polyalkylene terephthalate, it is possible to impart excellent gas barrier properties to this resin.

DETAILED DESCRIPTION OF THE INVENTION The co-condensed polyester of the present invention, its production method, and its uses will be specifically described below.

The co-condensed polyester of the present invention is basically composed of dicarboxylic acid component units and diol component units.

In the co-condensed polyester of the present invention, the dicarboxylic acid component units include a mononuclear aromatic dicarboxylic acid component unit (I) having an isophthalic acid component unit as a main component, and 2, a tonaphthalene dicarboxylic acid component unit. This is a dinuclear aromatic dicarboxylic acid component unit (b) as a main component.

Further, the diol component unit is a diol component unit (c) having an ethylene glycol component unit as a main component.

In addition to the above dicarboxylic acid component units and diol component units, the co-condensed polyester of the present invention contains
It may also contain a polyfunctional component unit (d).

Therefore, the co-condensed polyester of the present invention includes a ternary or more co-condensed polyester consisting of a mononuclear aromatic dicarboxylic acid component unit (1), a dinuclear aromatic dicarboxylic acid component unit (b), and a diol component unit (c). A quaternary or higher cocondensation consisting of a condensed polyester, a mononuclear aromatic dicarboxylic acid component unit (1) a dinuclear aromatic dicarboxylic acid component unit (b) a diol component unit (c), and a polyfunctional component unit (d) Polyester is included.

The mononuclear aromatic dicarboxylic acid component unit (1) constituting the co-condensed polyester of the present invention has an isophthalic acid component unit as its main component unit. The content of isophthalic acid component units in the co-condensed polyester is generally in the range of 50 to 100 mol%, preferably 70 to 100 mol%, based on the mononuclear aromatic dicarboxylic acid component units.

In the present invention, mononuclear aromatic dicarboxylic acid component units (1
Examples of the mononuclear aromatic dicarboxylic acid component units other than the isophthalic acid component units constituting the above include component units derived from terephthalic acid and component units derived from phthalic acid. The content of the above-mentioned component units other than isophthalic acid in the co-condensed polyester is usually as follows with respect to the mononuclear aromatic dicarboxylic acid component unit:
It is within the range of 0 to 50 mol%, preferably 0 to 30 mol%. In addition, when the above-mentioned mononuclear aromatic dicarboxylic acid component units other than isophthalic acid are contained in the co-condensed polyester, the above-mentioned content rate is the total content rate.

The dinuclear aromatic dicarboxylic acid component unit (b) constituting the co-condensed polyester of the present invention has a 2,6-naphthalene dicarboxylic acid component unit as a main component unit. The content of 2,6-naphthalene dicarboxylic acid component units in the co-condensed polyester is usually 50 to 100 mol%, preferably 70 to 100% by mole, based on the dinuclear aromatic dicarboxylic acid component units.
It is within the range of ~100 mol%.

In the present invention, mononuclear aromatic dicarboxylic acid component units (I
), the mononuclear aromatic dicarboxylic acid component unit other than 2,6-naphthalene dicarboxylic acid is, for example, 2
．． A component unit derived from 7-naphthalene dicarboxylic acid, a component unit derived from l,4-naphthalene dicarboxylic acid, a component unit derived from 1,6-naphthalene dicarboxylic acid, a component unit derived from 4,4'-biphenyl dicarboxylic acid Examples include component units derived from dinuclear aromatic dicarboxylic acids having 12 to 18 carbon atoms, such as the component units derived from dicarboxylic acids having 12 to 18 carbon atoms.

The content of the dinuclear aromatic dicarboxylic acid component units other than 26-naphthalene dicarboxylic acid in the co-condensed polyester is usually 0 to 50 mol%, preferably 0 to 50 mol%, based on the dinuclear aromatic dicarboxylic acid component units. It is within the range of 0 to 30 mol%.

In addition, when the above-mentioned dinuclear aromatic dicarboxylic acid component units other than 2,6-naphthalene dicarboxylic acid are contained in the co-condensed polyester, the above content rate is the total content rate.

The diol component unit (b) constituting the co-condensed polyester of the present invention has ethylene glycol component units as its main component unit.The content of the ethylene glycol component unit in the co-condensed polyester is as follows: Usually 50-100 mol%, preferably 70-1
It is within the range of 00 mol%.

In the present invention, diol component units other than tyrene glycol constituting diol component units include, for example,
, component unit derived from 3-propanediol, 11
A component unit derived from 4-butanediol, a component unit derived from neopentyl glycol, a component unit derived from cyclohexanediol, a component unit derived from cyclohexane dimetatool, 1.4-bis(β
- component unit derived from -hydroxyethoxy)benzene, + component unit derived from 3-bis(β-hydroxyethoxy)benzene, component derived from 2.2-bis(4-β-hydroxyethoxyphenyl)propane unit, a component unit derived from a diol having 3 to 15 carbon atoms, such as a component unit derived from bis(4-β-hydroxyethoxyphenyl)sulfone. The content of diol component units of ethylene glycol in the co-condensed polyester is generally in the range of 0 to 50 mol%, preferably 0 to 30 mol%, based on all diol component units. In addition, when the above-mentioned diol component units other than ethylene glycol are contained in the co-condensed polyester, the above-mentioned content rate is the total content rate.

As mentioned above, the diol component unit (c) constituting the co-condensed polyester of the present invention is basically a component unit whose main component unit is ethylene glycol. It also includes component units derived from compounds having an ether bond formed by bonding components together. However, the amount of such component units in the co-condensed polyester is preferably 10 mol% or less based on the diol component unit (c).

The polyfunctional component unit (d) constituting the co-condensed polyester of the present invention has 3 or more, preferably 3 to 4 carboxyl groups and/or hydroxyl groups, and has 3 to 15 carbon atoms, preferably is a component unit derived from a polyfunctional compound ranging from 3 to 9.

That is, the polyfunctional component unit (d) contains 3! A component unit derived from a polyfunctional compound having I or more carboxyl groups, a component unit derived from a polyfunctional compound having three or more hydroxyl groups, and a total of three or more carboxyl groups and hydroxyl groups. There are component units derived from polyfunctional compounds having the following.

Specific examples of such polyfunctional component units include component units derived from polycarboxylic acids, component units derived from polyols, and component units derived from oxycarboxylic acids. Examples of component units derived from such polycarboxylic acids include trimellitic acid, trimesic acid, 33'5,6'-
Examples include component units derived from aromatic polybasic acids such as tetracarboxydiphenyl; component units derived from aliphatic polybasic acids such as butanetetracarboxylic acid, and components derived from polyols. Examples of units include component units derived from aromatic polyols such as phloroglucin, I, 2,4,6-tetrahydroxybenzene; aliphatic units such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol. Examples of component units derived from oxycarboxylic acids include component units derived from oxypolycarboxylic acids such as tartaric acid and malic acid. .

These polyfunctional component units may be used alone or in combination to form a co-condensed polyester.

In the co-condensed polyester of the present invention, the mononuclear aromatic dicarboxylic acid component unit (1) as described above has 25 to 42
It is contained in an amount within the range of mol%, preferably 25 to 41 mol%, more preferably 25 to 40 mol%, and the dinuclear aromatic dicarboxylic acid component unit (b) is 8 to 25 mol%.
The diol component unit (c) is contained in an amount within the range of mol%, preferably 9 to 25 mol%, more preferably 10 to 25 mol%, and the diol component unit (c) is contained in an amount of 48 to 50 mol%, preferably 49 to 25 mol%. It is contained in an amount within the range of 50 mol%.

In the co-condensed polyester of the present invention, the polyfunctional component unit (d) is 0 to 2 mol%, preferably 0
It is contained in an amount within the range of ~1 mol%. By controlling the amount of the polyfunctional component unit (d) to 0 to 2 mol %, the co-condensed polyester of the present invention can maintain a substantially linear structure.

Note that the total of the above a component units, b component units, C component units, and d component units is 100 mol%. Further, a diol component unit in which two or more diol components are ether bonded is not an ethylene glycol component unit, but is included in a diol component unit whose main component unit is ethylene glycol.

The co-condensed polyester of the present invention having such a composition is a substantially linear polyester.

Here it is practically linear! "Having" means that the polyester has a linear chain structure or a branched chain structure, and means that it does not have a gel-like crosslinked structure (network structure). This means that when 1 g of the co-condensed polyester of the present invention is dissolved in 20 ml of O-chlorophenol, the co-condensed polyester is completely dissolved in O-chlorophenol without any gel remaining. do.

When the co-condensed polyester of the present invention is composed of the mononuclear aromatic dicarboxylic acid component unit (1), the dinuclear aromatic dicarboxylic acid component unit (b) and the diol component unit (c), the co-condensed polyester is It has a linear structure. The co-condensed polyester of the present invention is made from the mononuclear aromatic dicarboxylic acid component unit (1), the dinuclear aromatic dicarboxylic acid component unit (b), the diol component unit (c), and the polyfunctional component unit (d). In this case, the co-condensed polyester has a branched structure.

The co-condensed polyester of the present invention has an intrinsic viscosity (value measured at 25°C in a 0-chlorophenol solvent) of 0.6 to 1.
,61/g, and furthermore, 0
．． It is preferably in the range of 6 to 1.2 dl/g. If the intrinsic viscosity of the co-condensed polyester becomes greater than 1,647/g, the melt moldability of the co-condensed polyester will decrease, and the stretchability will also decrease. Moreover, as this value becomes smaller than 0.5 dl/g, the mechanical strength of the co-condensed polyester and its stretched products decreases. And this intrinsic viscosity is 0.6 to 1.2
dj! The co-condensed polyester in the range of /g has particularly excellent melt moldability, and the molded article produced using the obtained co-condensed polyester also has good mechanical strength.

Further, the co-condensed polyester of the present invention needs to have a glass transition temperature of 70°C or higher, and furthermore, the co-condensed polyester must have a glass transition temperature of 70 to 90°C. Preferably. Since the co-condensed polyester has a glass transition temperature of 70° C. or higher as described above, the co-condensed polyester can be sufficiently dried. By performing sufficient drying, it is possible to effectively prevent the polyester from decomposing due to moisture contamination during melt molding, and therefore, for example, contamination of low molecular weight polyester into the molded product during the molding operation is reduced.

The co-condensed polyester of the present invention can be produced using conventionally known methods.

When employing the melt polycondensation method for producing the co-condensed polyester in the present invention, a so-called direct polycondensation method can be employed, or a so-called transesterification polycondensation method can also be employed.

To explain the melt polycondensation method more specifically, the raw material components are simultaneously or sequentially charged into the reaction system and heated, and these raw materials are subjected to esterification or transesterification (and in some cases, transesterification). In this method, an initial polycondensation product is formed by performing an ether exchange reaction, and then this initial polycondensation metal is heated to a temperature higher than the melting point of the substance to melt it and perform polycondensation.

That is, in the above method, the co-condensed polyester of the present invention comprises the mononuclear aromatic dicarboxylic acid component unit (Otori).
A mononuclear aromatic dicarboxylic acid component (1') capable of forming a mononuclear aromatic dicarboxylic acid component (1'), a dinuclear aromatic dicarboxylic acid component (b') capable of forming a dinuclear aromatic dicarboxylic acid component unit (b), a diol component unit (c) and a polyfunctional component (d) capable of forming a polyfunctional component unit (d).
') in a predetermined ratio is heated to a specific temperature to perform an esterification reaction or transesterification reaction with the above components, and then a copolycondensation reaction in the presence of a predetermined catalyst. can do.

In the method for producing the co-condensed polyester of the present invention described above, the mononuclear aromatic dicarboxylic acid component (1') capable of forming the mononuclear aromatic dicarboxylic acid component unit (a) is a mononuclear aromatic dicarboxylic acid component (1') containing isophthalic acid and any of these acid components. Mono- or diesters and esters of diols such as bis β-hydroxyethyl ester, and mononuclear aromatic dicarboxylic acid component units used with this isophthalic acid and its derivatives include acid components such as terephthalic acid and phthalic acid. Mention may also be made of mono- or diesters of these acid components and esters of diols, such as bisβ-hydroxyethyl ester.

However, isophthalic acid or its derivatives are used in an amount equal to that of other mononuclear aromatic dicarboxylic acids or derivatives thereof, with the isophthalic acid component unit in the co-condensed polyester being the main component unit.

The dinuclear aromatic dicarboxylic acid component (b') which can form the dinuclear aromatic dicarboxylic acid component unit (b) is 2゜6-naphthalene dicarboxylic acid or the mono- or diester and bis-β-hydroxyethyl ester of this acid component. is an ester of a diol such as 2.6-
Examples of dinuclear aromatic dicarboxylic acid component units used with naphthalene dicarboxylic acid and derivatives include:
2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1゜naphthalene dicarboxylic acid, 4.4
'-Biphenyldicarboxylic acid, etc., with 12 or more carbon atoms
Mention may be made of the 18 dinuclear aromatic dicarboxylic acids as well as the mono- or diesters of these acid components and esters of diols such as bisβ-hydroxyethyl ester. However, 2,6-naphthalene dicarboxylic acid and its derivatives are different from other dinuclear aromatic dicarboxylic acids or their derivatives in the co-condensed polyester.
, 6-naphthalene dicarboxylic acid component units are used in an amount that can serve as the main component unit.

Diol component (b) that can constitute the diol component unit (b)
') is ethylene glycol or a mono- or diester of this ethylene glycol.

The diol component used together with this ethylene glycol or its derivatives is, 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 .3 to 1 carbon atom such as 2-bis(4-β-hydroxyethoxyphenyl)propane and bis(4-β-hydroxyethoxyphenyl)sulfone
5 diols may be mentioned. However, 2,6-
Naphthalene dicarboxylic acid and its derivatives are used in an amount such that the 2,6-naphthalene dicarboxylic acid component unit in the co-condensed polyester can become the main component unit relative to other dinuclear aromatic dicarboxylic acids or derivatives thereof.

The polyfunctional component forming the polyfunctional component unit (d) is
It is a polyfunctional compound having three or more carboxyl groups and/or hydroxyl groups and a carbon atom number ranging from 3 to 15, or an ester thereof. Examples of such polyfunctional compounds include trimellitic acid, trimesic acid,
．． Aromatic polybasic acids such as 3', S, 5'-tetracarboxydiphenyl and esters of these compounds, aliphatic polybasic acids such as butanetetracarboxylic acid and esters of these compounds, phloroglucin,
1, 2, 4. Aromatic polyols such as S-tetrahydroxybenzene and esters of these compounds, glycerin, aliphatic polyols such as methylolethane, trimethylolpropane, pentaerythritol and esters of these compounds, tartaric acid, apple Mention may be made of acids such as oxypolycarboxylic acids and esters of these compounds.

The above-mentioned components are blended so that the component units derived from these components in the reaction system are approximately equal to the content of each component unit in the co-condensed polyester to be obtained.

Preferably, the mononuclear aromatic dicarboxylic acid component (1'
), the dinuclear aromatic dicarboxylic acid component (b'), the diol component (c'), and the polyfunctional component (d') are determined by the content of mononuclear aromatic dicarboxylic acid component units (1) in the reaction system. is 25 to 42 mol%, the content of the dinuclear aromatic dicarboxylic acid component unit (b) is 8 to 25 mol%, the content of the diol component unit (c) is 48 to 50 mol%, and the polyfunctional component unit ( It is blended so that the content of d) is 0 to 2 mol%. Note that ethylene glycol can also be used, for example, as a solvent for a catalyst, and is generally used in excess of the total molar amount of dicarboxylic acids introduced into the system.

Next, when the above raw material components are supplied to the reaction system in the form of diols and dicarboxylic acids, an esterification reaction is carried out, and when the raw material components are supplied to the reaction system in the form of esters, the ester is Carry out an exchange reaction. Furthermore, when the raw material components contain both, a transesterification reaction and an esterification reaction are performed. Such esterification reactions and transesterification reactions usually involve 180 to 260
C, preferably at a temperature in the range of 200 to 260C. In addition, in this esterification reaction and transesterification reaction, the heating temperature is kept at a relatively low temperature (such as in the above temperature range).
For example, the temperature may be set to 180 to 205°C), and then a relatively high temperature (for example, 205 to 260°C) may be used. Although the above reaction can be carried out under reduced pressure, normal pressure or elevated pressure, this reaction is usually carried out under elevated pressure. The pressure in this case is usually 0.6~
2,6kx/d, preferably 1.0-2.0kg10f
Under such conditions, this reaction usually takes 3 to 15 hours, preferably 4 to 10 hours.
Finish in time. Note that components such as water produced as a by-product of the above reaction are successively removed from the reaction system.

The above ester reaction or transesterification reaction can be carried out without using a catalyst or with a catalyst.

When carrying out the ester reaction or transesterification reaction using a catalyst, examples of the catalyst that can be used include metal compounds such as calcium, magnesium, lithium, zinc, cobalt, and manganese.

Examples of the forms of these compounds include oxides, hydroxides, halides, inorganic acid salts, and organic acid salts.

Furthermore, when carrying out this ester reaction or transesterification reaction, various additives such as a diethylene glycol production inhibitor, a heat stabilizer, a light stabilizer, a lubricant, a pigment, and a dye can be used.

Examples of the ethylene glycol production inhibitor used here include amines such as triethylamine and tri-n-butylamine, and quaternary ammonium compounds such as tetraethylammonium hydroxide and tetrabutylammonium hydroxide. . Examples of stabilizers such as heat stabilizers include phosphoric acid, phosphorous acid, hypophosphorous acid, and phosphorus compounds such as esters thereof.

In addition, some of the phosphorus compounds used as heat stabilizers during the above esterification reaction or transesterification reaction are
It may also act as a catalyst for the phosphorus compounds used in the next step, and some diethylene glycol generation inhibitors form salts, complexes, double salts, etc. with specific metals and are used in the next step. It may also act as a catalyst.

After carrying out the esterification reaction or the transesterification reaction in this manner, a cocondensation reaction using the reactants is carried out.

This co-condensation reaction is carried out in the presence of a catalyst consisting of a compound selected from the group consisting of germanium compounds, antimony compounds and titanium compounds and a phosphorus compound.

The compound selected from the group consisting of germanium compounds, antimony compounds, and titanium compounds used in the present invention can be used as germanium, antimony, or titanium alone, and also as oxides, hydroxides,
Halides, organic acid salts, complexes, double salts, alcoholades,
It can be used in forms such as phenolates.

Examples of such compounds include reaction products of germanium, antimony or titanium with tertiary amines such as tri-n-butylamine or triethylamine; antimony dioxide, titanium(I) oxide, titanium(■) oxide, Oxides such as germanium; alkoxides such as titanium tetrabutoxide, titanium tetramethoxide, titanium tetraisopropoxide, germanium butoxide, germanium ethoxide; reaction products of titanium (I) oxide and acetylacetonate, isopropyl tris ( Examples include p-dodecylbenzenesulfonyl) titanate and isopropyl tris(p-hydroxybenzenesulfonyl)titanate.

These catalysts can be used alone or as a mixture of two or more. The proportion of metals or their compounds constituting these catalysts is usually 10 to 10-1 atomic ratio of antimony, germanium, or titanium per mole of mononuclear aromatic dicarboxylic acid and dinuclear aromatic dicarboxylic acid. 2 gram atoms, preferably in the range of 5.times.10 to 5.times.10@-3 gram atoms.

Phosphorous compounds used as catalysts together with the above compounds include, for example, phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, and esters of the above-mentioned phosphoric acids such as monomethyl phosphoric acid or dimethyl phosphoric acid, as well as phosphines and phosphites. Examples include phosphorus compounds such as. The proportion of the phosphorus compound to be used is usually 10-5 to 10-2, preferably 2X10 to 5X10' grams, based on the atomic ratio of phosphorus to 1 mole of mononuclear aromatic dicarboxylic acid and dinuclear aromatic oxycarboxylic acid. Within the range of atoms.

Further, a compound selected from the group consisting of the above-mentioned germanium compounds, antimony compounds and titanium compounds,
The phosphorus compound is used in an atomic ratio of metal and phosphorus, usually in the range of 10:1 to 1:10, preferably 5:1 to 1:5.

Such catalysts can be added to the reaction system as they are, or can be added after being dissolved or dispersed in a solvent in which these catalysts can be dissolved or dispersed. Diols such as ethylene glycol can also be used as such a solvent, and the diols added to the reaction system as a catalyst act as a solvent for the catalyst and also as a raw material for the reaction.

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

The reaction temperature of the reaction in the presence of such a catalyst is 2
The temperature is 30 to 300°C, preferably 250 to 280°C, and more preferably 260 to 275°C. That is, the reaction product of the above-mentioned esterification reaction or transesterification reaction (and in some cases, ether exchange reaction) is brought into a molten state and a cocondensation reaction is carried out.

This cocondensation reaction can be carried out under increased pressure, normal pressure or reduced pressure, but it is preferably carried out under reduced pressure. Excess ethylene glycol is removed from the reaction system by performing the reaction under reduced pressure.

Further, the above cocondensation reaction is preferably carried out in an inert atmosphere.

By carrying out the co-condensation reaction in this way, the viscosity of the reactive product increases over time.

Although it also depends on other conditions such as reaction temperature,
Usually for 1 to 15 hours, preferably for 2 to 10 hours, the intrinsic viscosity [η] of the co-condensed polyester is 0.6 to 1.6 dj/
g, preferably within the range of 0.6 to 1.2 dl/g.

For example, the co-condensed polyester of the present invention obtained as described above can be used as a material for molded bodies, stretched molded bodies, and the like. That is, using the co-condensed polyester of the present invention, film-like, sheet-like, fibrous,
Molded bodies of various shapes such as a container shape can be obtained, and such molded bodies may also be stretched.

Among the molded products using the co-condensed polyester of the present invention, the stretched molded product will be explained first.

Films, sheets,
Stretched molded bodies in various forms such as fibers can be obtained.

As the co-condensed polyester used here, the co-condensed polyester of the present invention can be used alone,
Furthermore, the composition may contain commonly used additives such as inorganic fillers, lubricants, slip agents, antiblocking agents, stabilizers, antistatic agents, and pigments.

Any conventionally known method can be adopted as a method for producing a stretched molded article using the co-condensed polyester of the present invention.

In general, an original molded body such as a film or sheet formed using the above-mentioned co-condensed polyester alone or a composition in which the above-mentioned additives are blended as necessary is used as it is or at a temperature below the glass transition point. After cooling and solidifying, it is stretched at a temperature higher than the glass transition temperature, preferably at a temperature between the glass transition temperature and 80° C. higher than the glass transition temperature.

As a method for producing a stretched molded article using the co-condensed polyester of the present invention, for example, when the original molded article is a film or sheet, a method of stretching an unstretched film or sheet in a uniaxial direction (-axial stretching method), a method of stretching in the longitudinal direction and then further stretching in the transverse direction (two-wheel stretching method), a method of simultaneously stretching in the longitudinal and transverse directions (
Simultaneous biaxial stretching), after two-wheel stretching, one of the −
Examples include a method in which stretching is repeated in several directions, a method in which two wheels are stretched and then further stretched in both directions, and a so-called vacuum forming method in which stretch forming is performed by reducing the pressure in the space formed by a film or sheet and a mold. can.

Here, the stretching ratio when uniaxially stretching the co-condensed polyester is usually 1.1 to 10 times, preferably 1.
It is in the range of 2 to 8 times, particularly preferably 1.6 to 7 times.

In addition, the stretching ratio when producing a molded object by two-wheel stretching is
In the horizontal axis direction, usually 1.1 to 8 times, preferably 1.2 to 8 times
7 times, particularly preferably in the range of 1,6 to 6 times, and usually 1.1 to 8 times, preferably 1.2 to 7 times, particularly preferably 1,6 to 6 times in the vertical axis direction. be. Moreover, the stretched molded product of these co-condensed products may be a laminate of a sheet or film containing the co-condensed polyester and a sheet or film made of another resin. Methods for producing such laminates include a method in which an original molded body such as a film or sheet of co-condensed polyester is laminated with an original molded body such as a film or sheet of other resin, and then stretched; Examples include a method of adhering another resin film or sheet (which may be stretched) of the stretched condensate.

A stretched molded article using the co-condensed polyester of the present invention has excellent mechanical strength and gas barrier properties. In particular, it is effective for protecting electrical and electronic circuits and preventing corrosion of metals by using it as a coating for electrical components, electronic components, metal components, and the like. In addition, the stretched film of co-condensed polyester can be used for capacitors, etc. by utilizing its electrical properties.
It can also be effectively used for applications such as motors, transformers, and wire coatings. Furthermore, it can also be used as a film for food packaging etc. by taking advantage of its excellent gas barrier properties.

As mentioned above, the co-condensed polyester of the present invention exhibits good gas barrier properties even when used alone, but when used in combination with other thermoplastic resins, the gas barrier properties of the resulting molded article are significantly improved. You can improve your city. That is, the co-condensed polyester of the present invention can be used as a gas barrier agent.

In the present invention, when the co-condensed polyester is used as a gas barrier agent, the method of using the co-condensed polyester includes a layer prepared using the co-condensed polyester and a layer prepared using another thermoplastic resin. There are two methods: a method of laminating a molded body with a thermoplastic resin, and a method of obtaining a molded body using a resin composition in which a co-condensed polyester is blended with another thermoplastic resin.

Thermoplastic resins that can be used here include polyesters, polyamides, polycarbonates, polyolefins, and the like. Particularly in the present invention, it is preferable to use polyester such as polyalkylene terephthalate having ethylene terephthalate as a main constituent unit as the thermoplastic resin.

Furthermore, as the polyalkylene terephthalate constituting the laminate molded product using the co-condensed polyester of the present invention,
The content of ethylene terephthalate structural units is usually
Polyethylene terephthalate in the range of 50 mol% or more, preferably 70 mol% or more is preferred. 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.

Here, other aromatic dicarboxylic acid component units other than terephthalic acid component units include isophthalic acid,
Mention may be made of component units derived from phthalic acid, naphthalene dicarboxylic acid, and the like. The diol component units constituting the polyalkylene terephthalate are preferably ethylene glycol component units, but a small amount of other diol component units may be included in addition to the ethylene glycol component units. Examples of 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-bis(4-β-human axyethoxyphenyl)propane and bis(4-
Examples include component units derived from diols having 3 to 15 carbon atoms, such as β-hydroxyethoxyphenyl) sulfone.

Furthermore, in addition to the aromatic dicarboxylic acid component units and the diol component units, the polyalkylene terephthalate may also contain structural units derived from other polyfunctional compounds, if necessary.

Here, polyfunctional compounds forming component units derived from polyfunctional compounds include trimellitic acid, trimesic acid, and aromatic compounds such as 3,3', 5,6'-tetracarboxydiphenyl. aliphatic polybasic acids such as butanetetracarboxylic acid; aromatic polyols such as phloroglucin and l,2,4,6-tetrahydroxybenzene; glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol and oxypolycarboxylic acids such as tartaric acid and malic acid.

The content of terephthalic acid component units in such a polyalkylene terephthalate is usually in the range of 50 to 100 mol%, preferably 70 to 100 mol%, and aromatic components other than terephthalic acid component units are contained in the polyalkylene terephthalate. The content of group dicarboxylic acid component units is usually in the range of 0 to 50 mol%, preferably 0 to 30 mol%, and the content of ethylene glycol component units is usually in the range of 5 to 50 mol%.
0 to 100 mol%; preferably in the range of 70 to 100 mol%, and the content of diol component units other than ethylene glycol component units is usually in the range of 0 to 50 mol%, preferably 0 to 30 mol%. , and the content of polyfunctional compound component units is usually 0 to 2 mol%, preferably 0 to 2 mol%.
It is in the range of 1 mol%. In addition, the intrinsic viscosity [η] (value measured at 25°C in CD-chlorophenol) of such polyalkylene terephthalate is usually 0.6 to
1.6 dj/g, preferably in the range of 0.6 to 1.2 df/g, 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 50-120℃, preferably 60-100℃
in the range of ℃.

Next, a laminate molded product composed of a layer made of polyalkylene terephthalate as described above and a layer made of the co-condensed polyester of the present invention will be described.

Specifically, this laminate molded product includes a two-layer laminate molded product composed of two layers: a layer made of the co-condensed polyester of the present invention and a polyalkylene terephthalate layer whose main constituent unit is polyethylene terephthalate; A three-layer laminate molded product having a layer consisting of a polyalkylene terephthalate as an intermediate layer and a polyalkylene terephthalate layer as an amphoteric side layer; A laminate molded product, a laminate molded product having a four-layer structure or more in which layers made of co-condensed polyester and the above-mentioned polyalkylene terephthalate layers are alternately laminated, the multilayer laminate molded product having an outer layer comprising a polyalkylene terephthalate layer; A multilayer laminate molded product having a four-layer structure or more in which layers made of condensed polyester and the above-mentioned polyalkylene terephthalate layers are alternately laminated, the outer rain layer being composed of a layer made of co-condensed polyester; A multilayer laminate molded product having a four-layer structure or more in which layers made of polyester and the above-mentioned polyalkylene terephthalate layers are alternately laminated, the outermost layer being a layer made of co-condensed polyester and a polyalkylene terephthalate layer, etc. can be mentioned.

The above-mentioned laminate molded product can be used in various shapes such as a sheet-like product, a plate-like product, a tubular product, a hollow body, and a container. This laminate molded body can be manufactured by a conventionally known method.

The thicknesses of the co-condensed polyester layer and the polyalkylene terephthalate layer constituting such a laminate are not particularly limited, and can be appropriately determined depending on the intended use of the laminate. For example, when this laminate molded product is the above-mentioned two-layer laminate molded product, the thickness of the layer made of co-condensed polyester is usually 4 to 350 μm, preferably 6 to 2 μm.
00 μm, and the thickness of the polyalkylene terephthalate layer is 8 to 600 μm, preferably 10 to 500 μm.
It is in the range of m. In addition, when this laminate molded product is the former of the three-layer laminate molded product, the thickness of the intermediate layer made of co-condensed polyester is usually in the range of 4 to 350 μm, preferably 6 to 200 μm, and The respective thicknesses of both outer layers consisting of alkylene terephthalate layers are:
It is usually in the range of 4 to 300 μm, preferably 5 to 250 μm. Further, when the laminate molded product is the latter of the three-layer laminate molded products, the thickness of the intermediate layer made of the polyalkylene terephthalate layer is usually in the range of 8 to 600 μm, preferably 10 to 500 μm, and The thickness of both outer layers made of condensed polyester is usually 4 to 1.
00 μm1 is preferably in the range of 6 to 50 μm. Furthermore, even when the laminate molded product is a multilayer laminate molded product having the above-mentioned four-layer structure or more, the thickness of the intermediate layer and the outermost layer constituted by the layers made of co-condensed polyester and the thickness constituted by the polyalkylene terephthalate layer. The thickness of the middle layer and the outermost layer can be selected as described above.

Such a laminate molded product has excellent properties such as stretchability, electrical properties, especially electrical insulation properties, mechanical strength, transparency, and gas barrier properties.

The above-mentioned laminate can further be made into a stretch molded product. That is, the stretched laminate molded product can be produced by stretching the laminate molded product. The stretched laminate molded product includes a -axially stretched laminate molded product and a biaxially stretched laminate molded product, and the stretched laminate molded product may be in any shape such as a film, a sheet, or a plate. As for the stretching ratio of such a stretched laminate molded product, the ratio proposed for the above-mentioned co-condensed polyester stretched molded product can be directly applied, and it is also possible to heat set the stretched molded product.

A stretched laminate molded product using the co-condensed polyester of the present invention has excellent properties such as mechanical strength, transparency, and gas barrier properties. In particular, when the stretched molded product is a film, it can be used, for example, as a coating for electrical parts, electronic parts, or metal parts to protect electrical and electronic circuits for a long period of time or to effectively prevent corrosion of metal parts. I can do it. The stretched laminated film is also highly useful as a material for capacitors, motors, transformers, and wire coatings.

Furthermore, the stretched laminated film can also be used as a food packaging material. Moreover, since the above-mentioned stretched laminate molded product has excellent properties, it can also be used as containers for foods and carbonated beverages.

Next, a resin composition in which the co-condensed polyester of the present invention is blended with another thermoplastic resin as a gas barrier property imparting agent will be described.

In such a resin composition, other thermoplastic resins that can be used include other thermoplastic resins used in the above-mentioned laminate, and in particular, among thermoplastic resins, thermoplastic resins similar to those mentioned above can be mentioned. It is preferable to use alkylene terephthalate, and a polyester resin composition using the same polyethylene terephthalate as above is particularly preferable.

In a polyester resin composition using such a co-condensed polyester, the blending ratio of the co-condensed polyester of the present invention is usually 1 to 500 parts by weight, preferably 2 to 3 parts by weight, per 100 parts by weight of the polyalkylene terephthalate.
00 parts by weight, particularly preferably from 3 to 100 parts by weight.

Although there are no particular limitations on the method for producing a polyester resin composition using the co-condensed polyester of the present invention, the general method is to uniformly mix the co-condensed polyester and polyethylene alkylate in a melt state or as a solution. especially,
It is preferable to employ a method of kneading both materials while dissolving them using a molding machine capable of mixing by stirring, such as an extrusion molding machine or an injection molding machine.

In addition to the polyalkylene terephthalate and the co-condensed polyester, this polyester resin composition also contains a nucleating agent, an inorganic filler, a lubricant, a slip agent, an anti-blocking agent, a stabilizer, an antistatic agent, an antifogging agent, and a pigment. It is also possible to mix various additives such as.

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

Such a polyester resin composition can be used as it is to form a molded article as described above, but it can also be made into a stretched molded article.

Stretched molded products of this polyester resin composition include -axially stretched molded products and biaxially stretched molded products, and the form thereof may be any one of a film, a sheet, and a fiber.

Any conventionally known method can be adopted as a method for producing a stretched molded article of this polyester resin composition. In general, an original molded body such as a film or sheet molded from the polyester resin composition is used as it is, or after being cooled and solidified to a temperature below the glass transition temperature of the composition, the temperature ranges from the glass transition temperature to the melting point, preferably from the glass transition temperature to the melting point. The stretching treatment is performed in a temperature range from the glass transition temperature to 80° C. higher than the glass transition temperature. Further, the heat setting treatment of the stretched molded product is carried out by heating for a short time at a temperature higher than the stretching temperature.

As a method for producing a stretched molded article of this polyester resin composition. When the original molded body is a film or sheet, examples of stretching methods that can be used include the above-mentioned uniaxial stretching method, biaxial stretching method, simultaneous biaxial stretching method, and any one of the following methods after biaxial stretching. Examples include a method in which stretching is repeated successively in the same direction, and a vacuum forming method.

Here, when there is a stretched stretched molded product of the polyester composition, the stretching ratio is usually 1.1 to 10.
times, preferably 1.2 to 8 times, particularly preferably 1.6 to
7 times the range. Further, when the stretched body is a biaxially stretched body, the stretching ratio in the longitudinal axis direction is usually 1.
1 to 8 times, preferably 1.2 to 7 times, particularly preferably 1
,6 to 6 times, and in the horizontal axis direction, it is usually 1.1
~8 times, preferably 1.2 to 7 times, particularly preferably 1,
It is in the range of 6 to 6 times. Moreover, it is also possible to produce a stretched molded article of these polyester resin compositions in the form of a laminate with other resins.

A method for producing a stretched laminate including a layer made of a polyester resin composition includes laminating an original molded body such as a film or sheet of a polyester resin composition with an original molded body such as a film or sheet of another resin, and then stretching. Examples include a method of bonding a film or sheet of another resin to a stretched molded product of a polyester resin composition.

The stretched molded product of the polyester resin composition thus obtained has excellent properties such as mechanical strength, transparency, and gas barrier properties, so it can be used in the shapes of films, sheets, tubular bodies, containers, bottles, etc. can be used.

(Margin below) Effect of the invention The present invention provides a novel co-condensed polyester.

Not only does this co-condensed polyester itself have excellent gas barrier properties, but it can also be used in combination with other thermoplastic resins to improve its thermoplastic properties without impairing the excellent properties of other thermoplastic resins. It is possible to impart excellent gas barrier properties to the resin.

This co-condensed polyester not only has excellent gas barrier properties but also excellent properties such as melt moldability and mechanical strength.

Furthermore, this co-condensed polyester can be easily produced by utilizing a co-condensation reaction of components that can constitute each component unit.

[Example] Next, the present invention will be specifically explained using Examples. However, the present invention should not be construed as limited by the Examples described below.

In the Examples and Comparative Examples shown below, the expression "parts" means "parts by weight" unless otherwise specified.

Further, performance evaluation of the co-condensed polyester of the present invention was performed according to the method described below.

Evaluation method The composition of the co-condensed polyester was identified by measuring the magnetic resonance spectrum of the obtained co-condensed polyester.

The intrinsic viscosity [η] was measured in 0-chlorophenyl at 25°C.

The glass transition temperature was determined using a differential scanning calorimeter at a heating rate of 10° C./min.

Gas barrier properties are determined by controlling the oxygen gas permeability coefficient (MOC).
Using an OITRAN device manufactured by ON),
Further, the carbon dioxide gas permeability coefficient was measured at 25° C. using a PERMATRAN C-IV device manufactured by MOKOM, and evaluation was made based on this value.

The hue was measured using a ND-1001DP color difference meter manufactured by Nippon Heavy Industries Ltd. The cloudiness is NDH manufactured by Nippon Heavy Industries.
It was measured using a -20D type haze meter.

To confirm that the co-condensed polyester is substantially on the line, add 1 g of the obtained co-condensed polyester to 20 ml of 0-chlorophenol (120°C), and confirm that the co-condensed polyester is completely dissolved and gel content is present. This was done by confirming that this was not the case.

Example 1 1,994 g of isophthalic acid, 649 g of 2,6-naphthalene dicarboxylic acid, 1,117 g of ethylene glycol, and 1.33 g of a 20% aqueous solution of tetraethylammonium hydroxide were charged into an autoclave, and the amount was 2 kg/al.
The reaction was carried out under a pressure of 200'C't' for about 2 hours with stirring. The reaction was then carried out at 250° C. for about 6 hours with stirring. Water produced during the above reaction was distilled out of the system.

Next, the reaction pressure was returned to normal pressure, and germanium dioxide and tetraethylammonium hydroxide were added to the reaction system.
A mixture solution containing 0% aqueous solution at a weight ratio of 2:8,
After adding 6 g and stirring for 10 minutes, 13 g of a 10% ethylene glycol solution of a mixture of monomethyl phosphate and dimethyl phosphate at a weight ratio of 5:5 was added.

Next, this mixture was heated to 250°C and reacted with stirring for about 1 hour, and the system was further heated to 270°C in about 1 hour, and the pressure of the system was reduced to about 0.8 mlg. The reaction was carried out under conditions of 0.8 to 0.6 mHH for about 6 hours. While the reaction was carried out as described above, unreacted ethylene glycol was distilled out of the system.

During this polycondensation reaction, the viscosity of the reactants increased over time.

The intrinsic viscosity of the co-condensed polyester obtained by this polycondensation reaction was 0.76 di/g.

Also, isophthalic acid in this co-condensed polyester, 2.
The content of each component unit of 6-naphthalene dicarboxylic acid, ethylene glycol, and diethylene glycol is 39.6 mol%, 10.6 mol%, and 48.4 mol%, respectively.
, 1.6 mol%.

The glass transition temperature of this co-condensed polyester is 71.6℃
Met.

It was also confirmed that this co-condensed polyester had a substantially linear structure.

After drying this co-condensed polyester at about 55°C for 20 hours under reduced pressure, about 100
A press sheet with a thickness of μm was prepared.

Next, the gas barrier properties of this press sheet were measured. As a result, the carbon dioxide permeability coefficient is 2.6 m1-country/d
・dx7-tjm, and the oxygen gas permeability coefficient is 0.
6 ml-+ma/nf-da7*atm.

Example 2 2330 g of dimethyl isophthalate, 733 g of 26-dimethylnaphthalene dicarboxylic acid ester, 2048 g of ethylene glycol, and 2.14 g of magnesium acetate tetrahydrate were charged into an autoclave, and the mixture was heated to 80 g at normal pressure.
The reaction was carried out with stirring for 1 hour at 200°C, for about 3 hours at 220°C, and for about 5 hours at 220°C, and the produced methanol was distilled out of the system.

A co-condensed polyester was produced in the same manner as in Example 1 except that the raw materials as described above were used and the operations were performed as described above.

The intrinsic viscosity of the obtained co-condensed polyester was 0.78 d
j/g. In addition, the compositions of each component unit of isophthalic acid, 2.6-naphthalene dicarboxylic acid, and ethylene glycol in this polycondensate are 39.7 mol% and 1 mol%, respectively.
They were 0.3 mol% and 49.1 mol%. The glass transition temperature of this co-condensed polyester was 72°C.

It was also confirmed that this co-condensed polyester had a substantially linear structure.

A press sheet of about 100 μm was produced using this co-condensed polyester.

The gas barrier permeability coefficient of this press sheet is 2.6ml#m/atmdj7 φ1t■
, and the oxygen gas permeability coefficient is 0.6ml・■/rI!・
It was du'tt■.

Examples 3 to 6 Cocondensation was carried out in the same manner as in Example 1 except that isophthalic acid, 2,6-naphthalene dicarboxylic acid, and ethylene glycol were used in the amounts listed in Table 1. produced polyester.

Table 1 shows the intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of these co-condensed polyesters.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Comparative Example 1 In Example 1, 2118 g of isophthalic acid, 2.
A co-condensed polyester was synthesized in the same manner except that 486 g of 6-naphthalene dicarboxylic acid was used.

The intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of these co-condensed polyesters are listed in Table 1.

Comparative Example 2 Polyethylene terephthalate having an intrinsic viscosity of 0.79617 g was synthesized from terephthalic acid and ethylene glycol according to a conventional method.

A press sheet was also produced from this polyethylene terephthalate in the same manner as in Example 1 except for one thing.

The carbon dioxide permeability coefficient of this press sheet is 25m1・Kaku/
rd - dg7 - glm, and the oxygen gas permeability coefficient is 4.6 ml・wa/rl・dx7・sl
It was m.

Examples 7 and 8 A co-condensed polyester was produced in the same manner as in Example 1, except that a mononuclear dicarboxylic acid mixture prepared by mixing isophthalic acid and terephthalic acid in the amounts shown in Table 2 was used instead of isophthalic acid. did.

Table 2 shows the intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the obtained co-condensed polyester.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 9-11 In Example 1,! A co-condensed polyester was produced in the same manner, except that the amount of 1,1-tris(hydroxymethyl)ethane used was changed to the amount shown in Table 3, except that it was winterized.

The intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the obtained co-condensed polyester are listed in Table 3.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 12 to 14 In Example 1, the polyfunctional compounds listed in Table 4 were used in place of 1.1.1-tris(hydroxymethyl)ethane.
A co-condensed polyester was produced in the same manner except that the amount described was used.

Table 4 shows the intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the obtained co-condensed polyester.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 15 and 16 Co-condensed polyesters were produced in the same manner as in Example 1, except that the diol component shown in Table 5 was added in the amount shown in Table 5 when the raw materials were charged.

Table 5 shows the intrinsic viscosity, composition of each component, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the obtained co-condensed polyester.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 17 and 18 In Example 1, a 10% ethylene glycol solution of the tertiary amine listed in Table 6 was used in place of the 20% aqueous solution of tetraethylammonium hydroxide in the amount listed in Table 6, and phosphoric acid 5 of dimethyl and monomethyl phosphate
Instead of 10% ethylene glycol in the 0150 mixture,
A co-condensed polyester was produced in the same manner except that the phosphorus compounds listed in Table 6 were used in the amounts listed in Table 6.

The intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the obtained co-condensed polyester are listed in Table 6.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 19-21 In Example 1, the polycondensation catalyst shown in Table 7 was used in the amount shown in Table 7 instead of the 2:8 (weight ratio) mixture of germanium dioxide and 2% tetraethylammonium hydroxide aqueous solution. A co-condensed polyester was produced in the same manner except for the following steps.

Table 7 shows the intrinsic viscosity, composition of each component unit, glass transition temperature, and carbon dioxide permeability coefficient of the press sheet of the co-condensed polyester obtained.

In addition, it was confirmed that the obtained co-condensed polyester was substantially linear.

Examples 22 to 24 and Comparative Example 5 Using the co-condensed polyesters produced in Examples 1, 3.7 and Comparative Example 2, four types of press sheets with a thickness of 200 μm were produced.

Furthermore, using a biaxial stretching device, these press sheets are
Two-wheel stretched films of each co-condensed polyester having an average thickness of 20 μm were prepared by simultaneously stretching the co-condensed polyesters by a factor of 3 in the longitudinal and transverse directions in a temperature range of approximately 75 to 110°C.

Table 8 shows the carbon dioxide permeability coefficients of these biaxially stretched films.

Example 25 The co-condensed polyester obtained from the isophthalic acid, 2,6-naphthalene dicarboxylic acid, and ethylene glycol produced in Example 1 was extruded at about 240°C using an extruder equipped with a lower die. An extruded sheet with a thickness of 200 μm was produced. Furthermore, this extruded sheet is first stretched 3 times in the vertical axis direction (parallel to the extrusion flow), then in the horizontal axis direction (
Stretched 3 times in the direction (perpendicular to the extrusion flow) to a thickness of approximately 2
A biaxially stretched film of 2 μm was produced. The carbon dioxide gas permeability coefficient of this two-wheel stretched film is 1.7ml.
-1ls.

Example 26 Approximately 150 μm press sheet of co-condensed polyester made from isophthalic acid, 2,6-naphthalene dicarboxylic acid, and ethylene glycol produced in Example 1 and Comparative Example 2
Approximately 150 μm of polyethylene terephthalate manufactured by
The press sheets were stacked and further press-molded to produce a multilayer press sheet with a thickness of 150 μm.

The adhesion of this multilayer press sheet to the co-condensed polyester layer was good.

Further, this multilayer press sheet was biaxially stretched under the same conditions as in Example 22 to produce a two-wheel stretched film having an average thickness of 18 μm.

The thickness of both the co-condensed polyester layer and the polyethylene terephthalate layer of this two-wheel stretched film is approximately 9 μm.
Therefore, it was confirmed that both the co-condensed polyester layer and the polyethylene terephthalate layer were uniformly stretched.

Furthermore, the adhesion between the co-condensed polyester layer and the polyethylene terephthalate layer of this biaxially stretched film was also good. Furthermore, the carbon dioxide gas permeability coefficient of this two-wheel stretched film was 1.8 m1-■/rrl-dx7@SI-.

Claims (3)

[Claims] (1) (a) Mononuclear aromatic dicarboxylic acid component unit whose main component unit is isophthalic acid component unit; 25 to 42 mol%, (b) Main component unit whose main component unit is 2,6-naphthalene dicarboxylic acid component unit A dinuclear aromatic dicarboxylic acid component unit;
8 to 25 mol%, (c) diol component units whose main component units are ethylene glycol component units; 48 to 50 mol%, and (d) having a total of 3 or more carboxyl groups and/or hydroxyl groups. , and a polyfunctional component unit derived from a polyfunctional compound having a carbon atom number in the range of 3 to 15; 0 to 2 mol% (however, the total of a, b, c, and d component units is 100 mol %), and the intrinsic viscosity [η] of the polyester is 0.5 to 1.5.
dl/g and the glass transition temperature is 70℃
A co-condensed polyester characterized by the above. (2) The content of mononuclear aromatic dicarboxylic acid component units (a) is 25 to 42 mol%, the content of dinuclear aromatic dicarboxylic acid component units (b) is 8 to 25 mol%, and the diol component unit ( c) content of 48 to 50 mol% and polyfunctional component unit (d) content of 0 to 2 mol% (however, a, b
(a') a mononuclear aromatic dicarboxylic acid component whose main component is isophthalic acid or its ester, (b'
) a dinuclear aromatic dicarboxylic acid component whose main component is 2,6-naphthalene dicarboxylic acid or its ester, (c') a diol component whose main component is ethylene glycol, and (d') a carboxyl group and/or a hydroxyl group. A mixture prepared by blending a polyfunctional component consisting of a polyfunctional compound having 3 or more groups and a carbon atom number in the range of 3 to 15 or an ester thereof is heated to perform an esterification reaction or After carrying out the transesterification reaction, a copolycondensation reaction is carried out at a temperature within the range of 230 to 300°C in the presence of a catalyst consisting of a phosphorus compound and a compound selected from the group consisting of germanium compounds, antimony compounds, and titanium compounds. A method for producing co-condensed polyester. (3) (a) Mononuclear aromatic dicarboxylic acid component units whose main component units are isophthalic acid component units; 25 to 42 mol%; (b) 2,6-naphthalene dicarboxylic acid component units as the main component units A dinuclear aromatic dicarboxylic acid component unit;
8 to 25 mol%, (c) diol component units whose main component units are ethylene glycol component units; 48 to 50 mol%, and (d) having a total of 3 or more carboxyl groups and/or hydroxyl groups. , and a polyfunctional component unit derived from a polyfunctional compound having a carbon atom number in the range of 3 to 15; 0 to 2 mol% (however, the total of a, b, c, and d component units is 100 mol %), is substantially linear, has an intrinsic viscosity [η] in the range of 0.5 to 1.5 dl/g, and has a glass transition temperature of 70°C or higher. A gas barrier agent characterized by comprising: