JPH07238154A - Polyester copolymer resin and hollow vessel made therefrom - Google Patents

Abstract

PURPOSE:To obtain a polyester copolymer resin used as a molding material and having transparency, heat resistance and impact resistance. CONSTITUTION:This polyester copolymer resin is one wherein the constituent dicarboxylic acid component mainly consists of terephthatlic acid and the constituent glycol component comprises 10-80mol% compound of formula I and 10-80mol% compound of formula II (wherein m and n each is 1-5; and p is 2-4).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester resin for molding materials having transparency, heat resistance, and impact resistance, and a hollow container using the same.

[0002]

2. Description of the Related Art Currently,
Polyethylene terephthalate (PET) is a material widely used as a transparent packaging material. PET
By stretching, a molded product having excellent impact resistance can be obtained. However, if stretching is not performed, PET
The impact resistance is still insufficient, and when a molding method such as extrusion molding that does not involve stretching is used, the strength of the molded body becomes low. For this reason, PET molding often uses a molding method involving stretching. Molding with stretching,
There was a drawback that the structure and control of the device became complicated. If a sufficiently strong polyester can be obtained without stretching, it is possible to more easily process the polyester having excellent transparency into a molded body.

The same applies to containers, such as polyvinyl chloride,
Polyethylene and other containers are molded by extrusion blow molding,
In the case of PET, the preform is once molded by injection molding,
After that, it is usual to perform container molding by injection biaxial stretch blow molding in which stretch blow is performed, which complicates the structure and control of the device and requires running costs such as molds, which is suitable for mass production, but a small amount. Not suitable for many varieties. When PET is subjected to extrusion blow molding, there is a problem that the drawdown is large, crystallization occurs, and it is difficult to obtain a uniform transparent container, and the PET container that is not stretched has insufficient impact strength.

Polyvinyl chloride is widely used as a material for packaging materials because it has excellent properties such as moldability and impact resistance. However, in recent years, there is a tendency that there is a problem that polyvinyl chloride containing chlorine atoms may adversely affect the global environment, such as the generation of hydrogen chloride by incineration. It is on the decline. Therefore, if a resin capable of direct blow molding, which has transparency and impact resistance, can be obtained instead of polyvinyl chloride, the capital investment of a molding machine can be dispensed with, and its significance is significant.

As such a polyester resin, a polyester prepared by copolymerizing cyclohexanedimethanol or isophthalic acid has already been known, but a container having a small capacity causes no problem, but a relatively large container having a capacity of 500 ml to 1 liter is resistant. There was a problem that the impact strength was insufficient.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that transparency, heat resistance,
The present invention has been completed by finding a specific copolyester resin having impact resistance, finding that the polyester resin is suitable for extrusion blow molding, and that the resulting hollow container is also excellent in transparency, heat resistance and impact resistance. Came to.

That is, in the present invention, the main component of the dicarboxylic acid component constituting the polyester is terephthalic acid, and the compound represented by the formula (I) and the formula (II) are used as the glycol component.
The compound represented by 10 to 80 mol% each in the glycol component
The present invention provides a copolyester resin, which is essentially contained within the above range, and a hollow container using the copolyester resin.

[0008]

[Chemical 2]

(In the formulas (I) and (II), m and n each represent an integer of 1 to 5, and p represents an integer of 2 to 4.) Of the dicarboxylic acid component constituting the polyester resin in the present invention, The main component is terephthalic acid, but other 20 mol%
You may contain other dicarboxylic acid in the range of less than. Other dicarboxylic acid components include isophthalic acid, 1,5-,
1,6-, 1,7-, 2,6- or 2,7-naphthalenedicarboxylic acid, phthalic acid, cyclohexanedicarboxylic acid, dibromoisophthalic acid, sodium-sulfoisophthalic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenylsulfone Aromatic dicarboxylic acids such as dicarboxylic acid, diphenylketone dicarboxylic acid, diphenoxyethanedicarboxylic acid, phenylenedioxydiacetic acid, adipic acid, sebacic acid, succinic acid, glutaric acid, piperic acid, suberic acid, azelaic acid, undecadioic acid, Examples thereof include aliphatic dicarboxylic acids such as dodecadioic acid and a mixture of two or more kinds.

The glycol component constituting the copolymerized polyester resin of the present invention is at least a compound represented by the formula (I) (hereinafter abbreviated as compound (I)) and a compound represented by the formula (II) (hereinafter compound ( II) and abbreviated) are required to be included. In the formulas (I) and (II), m and n each represent an integer of 1 to 5, with 1 to 3 being particularly preferable. When m and n are more than 5, the glass transition temperature (Tg) of the polyester resin obtained by using them becomes low, and mechanical properties such as elastic modulus and tensile strength are deteriorated, which is not preferable.

As the compound (I), for example, 1,4-bis (2-hydroxyethoxy) benzene and 1,4-bis (2-hydroxyethoxyethoxy) benzene are preferably used, and 1,4-bis (2 -Hydroxyethoxy) benzene is particularly preferred. Examples of the compound (II) include 4,4'-bis (2-hydroxyethoxy) biphenyl, 4,4'-bis (2-hydroxyethoxy) terphenyl, 4,4'-bis (2-hydroxyethoxy) quat. Examples thereof include phenyl and 4,4′-bis (2-hydroxyethoxyethoxy) biphenyl. Among them, 4,4′-bis (2-hydroxyethoxy) biphenyl is particularly preferably used.

As glycol components other than the above-mentioned compounds (I) and (II) constituting the copolyester resin of the present invention, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octane Aliphatic glycols such as methylene glycol, decamethylene glycol, propylene glycol, neopentylene glycol, diethylene glycol and polyethylene glycol,
Alicyclic glycol such as cyclohexanedimethanol,
o, m, p-xylylene glycol, 2,2-bis (4
-Hydroxyethoxyphenyl) propane and aromatic glycols such as ethylene oxide and propylene oxide adducts thereof, or a mixture of two or more thereof. Of these, ethylene glycol is preferably used, and the compounds (I), (II) and glycols other than ethylene glycol are preferably used within the range of less than 20 mol% of the total glycol component of the copolyester resin.

The copolymerized polyester resin of the present invention contains the compound (I) and the compound (II) in the glycol component, respectively.
The content is 10 to 80 mol%, preferably 20 to 70 mol%, more preferably 30 to 60 mol%. When the amounts of the compound (I) and the compound (II) in the glycol component are less than 10 mol% or more than 80 mol%, the resin improving effect is small and only a polyester resin having a low impact strength can be obtained. In addition, it is important to combine both compounds (I) and (II). In either case, the impact strength is improved to some extent, but in the case of a large container of about 1000 ml, the impact strength is improved. The level is still insufficient.

In the copolyester resin of the present invention, hydroxycarboxylic acids such as glycolic acid, hydroxybenzoic acid and hydroxynaphthoic acid, hydroquinone, resorcinol, dihydroxydiphenyl, dihydroxydiphenyl ether and 2,2-bis (4-hydroxyphenyl) are further used. ) Diphenol such as propane may be copolymerized. As a method for synthesizing a polyester using these monomers, any method may be used as long as it is a general polyester synthesizing method such as a direct polycondensation method or a transesterification method.

Intrinsic viscosity of the copolyester resin of the present invention (phenol / tetrachloroethane (weight ratio 6/4)
0.5 dL / g or more is preferable, and 0.6 dL / g or more is more preferable. If it is less than 0.5 dl / g, the mechanical properties of the container obtained from this polyester resin are deteriorated, which is not preferable. The glass transition temperature (Tg) of the copolyester resin of the present invention for bottles is preferably 50 to 180 ° C, more preferably 60 to 150 ° C.

The copolymerized polyester resin of the present invention is PE
It has a higher impact resistance than T and can be molded into a sheet, a film, a bottle, and the like, but is particularly preferable as a polyester resin for extrusion blow molding, because extrusion blow molding is easy. It can be used for hollow containers. Further, various additives to the copolymerized polyester resin of the present invention as necessary, for example, a colorant, an antioxidant,
An ultraviolet absorber, an antistatic agent, a flame retardant and the like can be added.

The hollow container of the present invention can be produced by the usual extrusion blow molding method (direct blow molding method) or biaxial stretch blow molding method using the copolymerized polyester resin of the present invention. The method is preferably used. The hollow container obtained by the present invention is excellent in transparency, heat resistance, and mechanical strength, and thus is useful as a substitute container for a polyvinyl chloride container.

[0018]

The present invention will be described in detail below with reference to examples, but these examples do not limit the present invention. The intrinsic viscosity of the polymer was measured at 25 ° C. using a mixed solvent of phenol / tetrachloroethane (weight ratio 6/4). The glass transition temperature (Tg) was measured using a dynamic viscoelasticity measuring device RSA-2 manufactured by Rheometrics. The glass transition temperature was defined as the peak top of the loss elastic modulus when strain was applied at a cycle of 1 Hz. The impact resistance test is JIS-
According to K7110, using injection-molded specimens with a width of 2.5 mm,
A notched Izod impact test was performed and evaluated.

Further, the evaluation of the hollow container was carried out by the following items. <Moldability> It was evaluated whether or not it could be molded into a bottle shape. <Transparency> Evaluation was made by visual observation in three grades of ◯, Δ, and ×. ○: As transparent as PET △: Slightly hazy ×… Opaque <Impact resistance> Add 1000 ml of ion-exchanged water to the container, cap the container, and leave it at 23 ° C and 65% RH for 1 day. Then 1
It was dropped from the height of m to the concrete surface and indicated by how many times it cracked (n = 10 average). Dropped up to 5 times.

Example 1 100 mol (19.42 kg) of dimethyl terephthalate and 1,4-bis (2) were placed in a reactor equipped with a stirring blade, a nitrogen inlet and a pressure reducing port.
-Hydroxyethoxy) benzene (m = 1 in formula (I),
n = 1) 20 mol (3.96 kg), 4,4′-bis (2-hydroxyethoxy) biphenyl (p = 2 in the formula (II), m = 1,
n = 1) 20 mol (4.94 kg), ethylene glycol 160 mol
(9.93 kg), 10 g each of zinc acetate and germanium dioxide as a catalyst were charged. The mixture was heated to 180 ° C under a nitrogen stream to carry out a transesterification reaction, and methanol was distilled off. After 4 hours, the theoretical amount of methanol was distilled off, so the temperature was raised to 270 ° C and the pressure was gradually reduced to 0.1 to 0.3 Torr.
Polymerized for hours. As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 19 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene unit, 20 mol% was 4,4'-bis (2-hydroxyethoxy) biphenyl unit, and 61 mol% was ethylene glycol unit. The physical properties of the resin are shown in Table 1.

After crushing the obtained polymer with a crusher,
Dry at 80 ° C for 1 day, and use an extrusion blow molding machine manufactured by Tahara Seisakusho, capacity about 1000ml, height about 185mm, body width (maximum value) about 105mm, body depth (maximum value) about 85mm, mouth A flat container (weight: about 60 g) having a diameter of about 23 mm was molded. The cylinder temperature was 200 to 250 ° C and the mold temperature was 10 to 40 ° C.
Moldability, transparency and impact resistance of the obtained container were evaluated. The results are shown in Table 1.

Example 2 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
A polymer was synthesized in the same manner as in Example 1 except that the amount was 30 mol (5.94 kg), 30 mol (7.41 kg), and 140 mol (8.68 kg). As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 28 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene unit, 29 mol% was 4,4'-bis (2-hydroxyethoxy) biphenyl unit, and 43 mol% was ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Example 3 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
A polymer was synthesized in the same manner as in Example 1 except that the amount was 40 mol (7.92 kg), 40 mol (9.88 kg), and 120 mol (8.68 kg). As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 39 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene units, 39 mol% were 4,4'-bis (2-hydroxyethoxy) biphenyl units, and 22 mol% were ethylene glycol units. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Example 4 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
50 mol (9.90 kg), 50 mol (12.35 kg), 100 mol (6.20 kg)
A polymer was synthesized in the same manner as in Example 1 except that
As a result of ¹ H-NMR analysis of the obtained polymer,
100 mol% of dicarboxylic acid residues constituting polyester
Is a terephthalic acid unit, 48 mol% of the glycol component is 1,4-bis (2-hydroxyethoxy) benzene unit, 49 mol% is 4,4′-bis (2-hydroxyethoxy) biphenyl unit, 3 mol% Was an ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Example 5 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
A polymer was synthesized in the same manner as in Example 1 except that the amount was 30 mol (5.94 kg), 20 mol (4.94 kg), and 150 mol (9.3 kg). As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 30 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene unit, 20 mol% was 4,4'-bis (2-hydroxyethoxy) biphenyl unit, and 50 mol% was ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Example 6 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
A polymer was synthesized in the same manner as in Example 1 except that the amount was 70 mol (13.86 kg), 30 mol (7.41 kg), and 100 mol (6.2 kg). As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 68 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene unit, 29 mol% was 4,4'-bis (2-hydroxyethoxy) biphenyl unit, and 3 mol% was ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Example 7 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
30 mol (5.94 kg), 50 mol (12.35 kg), 120 mol (7.44 kg)
A polymer was synthesized in the same manner as in Example 1 except that
As a result of ¹ H-NMR analysis of the obtained polymer,
100 mol% of dicarboxylic acid residues constituting polyester
Is a terephthalic acid unit, 29 mol% of the glycol component is 1,4-bis (2-hydroxyethoxy) benzene unit, 50 mol% is 4,4′-bis (2-hydroxyethoxy) biphenyl unit, 21 mol% Was an ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Comparative Example 1 Polyethylene terephthalate was synthesized from only dimethyl terephthalate and ethylene glycol, and a container was formed by direct blow molding as in Example 1. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Comparative Example 2 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), ethylene glycol charge 5 mol (0.99 kg), 5 mol (1.24 kg), 190 mol (11.78 kg), respectively
A polymer was synthesized in the same manner as in Example 1 except that
As a result of ¹ H-NMR analysis of the obtained polymer,
100 mol% of dicarboxylic acid residues constituting polyester
Is a terephthalic acid unit, 5 mol% of the glycol component is 1,4-bis (2-hydroxyethoxy) benzene unit, 5 mol% is 4,4'-bis (2-hydroxyethoxy) biphenyl unit, 90 mol% Was an ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding.

Comparative Example 3 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1), the amount of ethylene glycol charged respectively
A polymer was synthesized in the same manner as in Example 1 except that the amount was 20 mol (3.96 kg), 0 mol, and 180 mol (11.78 kg). As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 20 mol% of the glycol component was 1,4-bis (2-hydroxyethoxy). ) Benzene unit, 80 mol% was ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding. This resin has an impact strength of 600
Although there is no problem if it is a container of about ml,
It was slightly fragile in a large container such as 1000 ml.

Comparative Example 4 1,4-bis (2-hydroxyethoxy) benzene (m = 1, n = 1 in the formula (I)), 4,4'-bis (2-hydroxyethoxy) biphenyl (formula (II ), P = 2, m =
1, n = 1) and the amount of ethylene glycol charged were 0 mol, 20 mol (4.94 kg) and 180 mol (11.78 kg), respectively, and a polymer was synthesized in the same manner as in Example 1. As a result of ¹ H-NMR analysis of the obtained polymer, 100 mol% of the dicarboxylic acid residues constituting the polyester were terephthalic acid units, and 20 mol% of the glycol component was 4,4'-bis (2-hydroxy). Ethoxy) biphenyl unit, 80 mol% was ethylene glycol unit. Table 1 shows the physical properties of the resin and the physical properties of the container obtained by direct blow molding. This resin has an impact strength of 600
Although there is no problem if it is a container of about ml,
It was slightly fragile in a large container such as 1000 ml.

Comparative Example 5 PETG67, a commercially available resin, manufactured by Eastman Chemical Company
63 (100 mol% of acid component is terephthalic acid unit, about 30 mol% of diol component is cyclohexanedimethanol unit, about 70 mol% is ethylene glycol unit)
Table 1 shows the physical properties of the resin when used with and the physical properties of the container obtained by direct blow molding.

[0033]

[Table 1]

Claims (2)

[Claims] 1. The main component of the dicarboxylic acid component constituting the polyester is terephthalic acid, and the compound represented by the formula (I) and the compound represented by the formula (II) are contained in the glycol component in an amount of 10 to 10 each. A copolyester resin, which is essentially contained within the range of 80 mol%. [Chemical 1] (In the formulas (I) and (II), m and n each represent an integer of 1 to 5, and p represents an integer of 2 to 4.) 2. A hollow container comprising the copolymerized polyester resin according to claim 1.