JPS612729A - Copolyester - Google Patents

Abstract

PURPOSE:To provide a copolyester of outstanding mechanical properties, adhesivity, especially gas-barrier characteristics, constituted, as chief structural units, by ethylene-1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate unit and ethylene isophthalate one. CONSTITUTION:The objective copolyester constituted, as chief structural units, by (A) 21-75 (pref. 25-70) mol% of 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate unit of formula I and (B) 79-25 (pref. 75-30) mol% of ethylene isophthalate of formula II can be obtained, for example, by esterification between (1) 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid (2) isophthalic acid and (3) ethylene glycol followed by polycondensation, in the presence of a catalyst (e.g. tetrabutyl titanate) under a high vacuum at 220-300 deg.C. This copolyester has an intrinsic viscosity 0.3-1.5 (pref. 0.4-1.2) in orthochlorophenol at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a novel copolyester having extremely excellent gas barrier properties.

Prior Art> Thermoplastic polyester resin, mainly made of polyethylene terephthalate, is used in various containers and films due to its excellent mechanical properties, gas barrier properties, chemical resistance, fragrance retention, and hygiene. It is processed into sheets, etc. and widely used as packaging materials.

However, in recent years, there has been a demand for further improvement in gas barrier properties against oxygen in many applications. For example, containers for foods such as carbonated beverages are required to have high gas barrier properties, and hollow containers made of biaxially oriented polyethylene terephthalate are said to have insufficient gas barrier properties.

It is known that gas barrier properties are improved by substituting part or all of polyethylene terephthalate with isophthalic acid [for example, R, R4, light et al.
Polymer Engine-eering an
d 5science 22. (14) 85
7 (1982)).

<Problems to be Solved by the Invention> However, it has been found that even these polyesters still have insufficient gas barrier properties.

In other words, the gas barrier properties of conventionally known gas barrier properties are completely unsatisfactory for containers that are under pressure, such as those used for carbonated beverages, and the gas inside the container gradually dissipates (unavoidable). It is.

Additionally, the present inventors previously discovered that polyethylene-1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate has relatively good gas barrier properties. However, it was found that even this polyester did not have sufficient gas barrier properties.

That is, at present, a polyester having high gas barrier properties has not yet been found, and there has been a demand for a polyester having high gas barrier properties.

Therefore, the present inventors conducted intensive research with the aim of providing a new polyester having excellent gas barrier properties that conventional polyesters cannot achieve, and as a result, they arrived at the present invention.

means and actions for solving the problems, i.e.
The present invention comprises polyethylene-1,2-bis(2-chlorophenoxy)ethane-4゜4'-dicarboxylic acid ray-1 units with 21 to 75 mol% and 79 ethylene isophthalate units.
It is a copolymerized polyester containing -25 mol% as a main component.

Polyethylene-1,2-bis(
2-chlorophenoxy)ethane-4,4'-dicarboxylate copolymers are taught in Japanese Patent Publication No. 1795/1983. However, this publication does not contain any description or indication of a copolymer in which 25 mol % or more of isophthalic acid is copolymerized as a dicarboxylic acid component and its unique excellent effects, that is, excellent gas barrier properties.

The present invention will be specifically explained below.

The copolymerized polyester of the present invention is polyethylene-1,2
-Bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate units of 21 to 75 mol% and ethylene isophthalate units of 79 to 25 mol% are the main constituents.

Preferably, 25 to 70 mol% of polyethylene-1,2-bis(2-chlorophenoquine)ethane-4,4'-dicarboxylate units and 75 mol% of ethylene isophthalate units.
-30 mol% as the main constituent.

The proportion of ethylene 1,2-bis(2-chlorophenoxy)ethano-4,4'-dicarboxylate units is 21 mol%
If it is less than 75 mol%, the resulting molded product will have poor physical properties such as gas barrier properties, mechanical inertia, and adhesion.
If the amount is larger than this, the resulting molded product will have low gas barrier properties, low bending strength, and low impact strength, which is not preferable.

It is desirable that the copolymerized polyester of the present invention has an intrinsic viscosity of 0.3 to 1.5, preferably 0.4 to 1.2, as measured in lusochlorophenol at 25°C.

The copolymerized polyester of the present invention includes 1°2-bis(
2-Chlorphenoquine) ethane-4,4'-dicarboxylic acid, dicarboxylic acid components other than isophthalic acid, diol components other than ethyleneglyfur, and oxycarboxylic acid components further copolymerized. included.

Other dicarboxylic acid components include, for example, succinic acid, adipic acid, sepanoic acid, terephthalic acid, 2,6-naphthalinodicarboxylic acid, 4,4'-diphenyldicarboxylic acid,
Hexahydroterephthalic acid, 1,2-bis(phenoxy)ethane-4+4'-dicarboxylic acid, 1,2-bis(2
-bromphenoxy)ethane-4+4'-dicarboxylic acid, l,2-bis(2,6-cyclolphenoquine)ethane-4,4'-dicarboxylic acid, 1-(2-chlorophenoxy)-2(phenoxy) Ethano-4,4'-dicarboxylic acid, etc., and other glycol components include - for example, polyethylene glycol, polypropylene glycol, tetramethylene glycol, hexamethylene glycol, 1,4-cyclohexane-dimetatool, diethylene glycol, neopentyl Glycol, 1.3-
Bis(β-hydroquinetoquine)benzene, bis(β-
Examples of the oxycarboxylic acid component include p-(β-
(oxyethoxy)benzoic acid. Among these, bis(β-hydroxyethoxy)bisphenol S is most preferred.

The copolyester of the present invention can be produced by any method.

For example, a method of directly polycondensing l,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid, isophthalic acid, and ethylene glycol, or a method of directly polycondensing 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid, ) ethane-4
, 4'-dicarboxylic acid ester, isophthalic acid ester, and ethylene glycol are preferably polycondensed by transesterification.

The direct polymerization method preferably uses l,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid and isophtha. After esterifying acid and ethylene glycol, in the presence of a polycondensation catalyst, under high vacuum,
This is a method of carrying out a polycondensation reaction at a temperature of 0°C, while the transesterification method is preferably a method in which dimethyl 1,2-bis(2-chlorophenoquine)ethane-4,4'-dicarboxylate, dimethyl isophthalate and ethylene This is a method in which glycol is transesterified at 130 to 260°C in the presence of a transesterification catalyst, and then subjected to polycondensation reaction at a temperature of 220 to 300°C under high vacuum in the presence of a polycondensation catalyst.

The main raw material is 21 to 75 mol% of 1.2-bis(2
A dicarboxylic acid component consisting of -chlorophenoxy)ethane-4,4'-dicarboxylic acid or its ester and 79 to 25 mol % of isophthalic acid or its ester, and a diol component mainly consisting of ethylene glycol are used.

When a small amount of other dicarboxylic acid components, diol components, and oxycarboxylic acid components are further copolymerized, raw materials for these components are used together with the main raw materials.

The polycondensation catalyst in the direct polymerization method and the transesterification method is preferably selected from compounds such as antimony, tin, lead, germanium, titanium, etc. Particularly preferred specific examples include tetrabutyl titanate, monobutyltin oxide, dibutyltin oxide, etc. , antimony dioxide, lead dioxide, and germanium dioxide. Further, the transesterification reaction catalyst is preferably selected from compounds such as calcium, magnesium, zinc, manganese, cobalt, and lithium, and particularly preferred specific examples include calcium acetate, magnesium acetate, zinc acetate, manganese acetate,
Examples include cobalt acetate and lithium acetate.

The amount of these catalysts to be used is preferably 0.01 to 1% by weight based on the resulting copolyester in the case of a polycondensation catalyst, and 0.03 to 0.31i% by weight in the case of a transesterification catalyst. It is. In addition, to prevent undesirable coloring during this polycondensation reaction, phosphorus compounds such as phosphoric acid, phosphoric acid esters (trimethyl phosphate, etc.), phosphorous acid, and phosphite esters (trimethyl phosphite, etc.) may be added. can.

In this way, the copolymerized polyester of the present invention is obtained.

The copolymerized polyester of the present invention melts! It is possible to melt-form a film or the like, thereby obtaining a molded product such as a film.

It is also possible to mold with a blow molding machine, and the parison can be blow molded with compressed gas using extrusion blow molding called direct blow molding or injection blow molding, or with a bottomed molding method called biaxial stretch blow molding. It is also possible to stretch the opening parison in the axial and circumferential directions and blow mold it.

The obtained T-co molded product has excellent gas barrier properties, mechanical properties, and adhesive properties, and is particularly excellent in gas barrier properties.

The copolymerized polyester of the present invention has extremely good adhesion with other polymers and can be laminated with other polymers such as polyethylene terephthalate, and can be used in coextrusion, dry lamination, and sandwich lamination.
The product is made into laminates such as film-like, cant-like, and tube-like products by molding, etc., and then into cup-like, bottle-like, and other laminate containers by injection molding, blow molding, two-wheel stretch blow molding, vacuum forming, compression molding, etc. You can also do that.

Furthermore, the molded article made of the copolymerized polyester of the present invention can be made of glass fiber, aromatic polyamide fiber, carbon fiber,
Copolymerized polyester 100 with fiber reinforcing materials such as cotton linters, powder reinforcing materials such as carbon black and white carbon, and flaky reinforcing materials such as aluminum flakes.
It can be blended in an amount of 1 to 100 parts by weight, and inorganic powders such as calcium carbonate, talc, mica, kaolin, barium sulfate, and silica can be blended as fillers.

Even when such reinforcing materials and fillers are blended, the gas barrier properties of the molded article made of the copolyester of the present invention are not substantially reduced.

<Example> The effects of the present invention will be explained in further detail with reference to Examples below.

Examples 1-3 1.2-bis(2-chlorophenoxy)ethane-4,4
'-': Dimethyl carboxylate and dimethyl isophthalate were prepared in the proportions shown in Table 1, and ethylene glycol 31
09ij (molar ratio of ethylene glycol to total dimethyl dicarboxylate is 2:1) and 7.0 parts of calcium acetate.
5 parts by weight of antimony trioxide and 4 parts by weight of antimony trioxide were charged into a reactor equipped with a rectification column, and the reaction temperature was gradually raised to 140 to 245°C over 4 hours while stirring to obtain 99% of the theoretical amount of methanol (
1,590 parts by weight) were distilled off, and 2 parts by weight of trimethyl phosphate were added.

Next, the transesterification reaction product of the starch was transferred to a polymerization furnace and 245
The temperature was raised to ~290℃ in 1 hour, and at the same time 0.0℃ in 1 hour.
A high vacuum of 5 tx Hg or less was applied, and polycondensation was further carried out for 2 hours under this high vacuum.

Thereafter, the pressure was returned to normal with nitrogen, and then the polymer was discharged into a water tank under pressure in a gut shape and cut into chips. The melting points (measured with a differential calorimeter (Perkin Elmer type I)) and intrinsic viscosities (measured at 25° C. in OJresochlorophenol) of these copolyesters are shown in Table 1.

After sufficiently drying the Kono copolymerized polyester, use an extruder (
3011jφ) and melt-extruded at a temperature 20 to 40° C. higher than the melting point, wound around a drum with a surface temperature of 60° C., cooled and solidified to produce an unstretched film with a thickness of 100 to 200 μm. Table 1 shows the results of measuring the oxygen permeation amount of this unstretched film using a modern control (Tooth oxygen permeability meter 0X-TRAN 100 model) at a temperature of 20° C. and a relative humidity of θ%.

In addition, the unstretched film of Example 2 was simultaneously biaxially stretched 2 to 3 times at 90 to 120°C using a film strainer manufactured by T, M, Long, and then the amount of oxygen permeation was measured. Shit co.

As is clear from Table 1, the copolyester of the present invention has excellent gas barrier properties.

On the other hand, it can be seen that the gas barrier properties of Comparative Examples 4 to 7 and polyethylene terephthalate are poorer than that of the copolyester of the present invention.

Further, the amount of oxygen permeation of the biaxially stretched film of Example 2 was 0.
4cc/m・24Hr10. 11.5 ccβ・24)1r1 of C++ and coaxially oriented polyethylene terephthalate
It turned out to be overwhelmingly better than 0.1 m.

It was confirmed that these co-No polyesters had copolymerization compositions as shown in Table m1 using 100MH 13CNivfR in orthochlorophenol at 140°C. In addition, the infrared absorption spectrum of the copolymerized polyester of Example 2 was measured and found to be 1405, +450.1500, 160.
It was found that it had a characteristic absorption at 0.1700 to 1730 cM'.

Example 4 A laminate sheet with a three-layer structure was prepared in which polyethylene terephthalate with an intrinsic viscosity of 0.91 was used as the polyester resin in the first and third layers, and the copolymerized polyester of Example 2 shown in Table 1 was used as the second layer. Molded by co-extrusion molding method (constituent ratio 1st layer: 2nd layer (adhesive layer); 3rd layer -5:l:5, second
Average layer thickness lOμ).

Next, the obtained laminated sheet was cut into a piece having a width of 10 ff and a length of 50 ff to form a test piece for evaluating adhesion. The third layer was applied to the first layer of the specimen at a rate of 20III/Iff to 90
Adhesive strength was determined by measuring the force m (t9/z) when pulling in the direction of .

As a result, the adhesive strength was extremely good at 1.50-2.0kq10x, and the oxygen permeation rate was 0.5C Shio・24
It was found to be excellent in Hrlo and l tx.

Effects of the present invention> The copolymerized polyester of the present invention has excellent gas barrier properties, mechanical properties, and adhesive properties, and is particularly effective in gas barrier properties.
It has excellent properties. Therefore, it can be widely used as a packaging material requiring high gas barrier properties.

Claims (1)

[Claims] A copolymerized polyester whose main constituents are 21 to 75 mol% of ethylene-1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate units and 79 to 25 mol% of ethylene isophthalate units.