JPH10195292A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition comprising a polyester consisting mainly of ethylene terephthalate units and a specific polyimide, capable of exhibiting excellent heat resistance and moldability in good balance and useful for hollow moldings such as drink bottles. SOLUTION: This resin composition comprises (A) a polyester wherein >=80wt.% of the constituting units are ethylene terephthalate units and (B) a polyimide comprising repeating units of the formula [R1 is a 4-12C alicyclic or aliphatic alkylene (substituted by a group non-reactive with the component A); A1 is an aromatic group (substituted by a group non-reactive with the component A) (preferably an amorphous polyimide from the view point of solubility with the component A) in an A:B weight ratio of 95:5 to 5:95. Thus, the heat resistance and moldability of the composition are improved in good balance, because the glass transition temperature of the component A is raised and because the melt viscosity of the component B are lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyester,
The present invention relates to a novel resin composition comprising a specific polyimide. More specifically, the present invention relates to a heat-resistant polyester composition suitable for a hollow molded article made of plastic, and a resin composition containing a polyimide composition and the like having greatly improved moldability.

[0002]

2. Description of the Related Art Among plastic materials, polyethylene terephthalate has excellent mechanical strength, heat resistance, transparency and gas barrier properties, so that it can be used for juices, soft drinks,
It is used as a material for containers for carbonated beverages, seasonings, detergents, cosmetics, and the like. However, depending on the application, sufficient heat resistance is not enough for sterilization, high temperature filling is not possible,
There are problems such as a low alkali cleaning temperature for recycling and inefficiency, and a decrease in content due to insufficient gas barrier properties. For this reason, the appearance of a polyethylene terephthalate hollow molded article having excellent heat resistance and good gas barrier properties has been desired.

[0003] Polyethylene terephthalate (PET) is made compatible with ULTEM (manufactured by General Electric Co.), which is an amorphous polyetherimide, to obtain PE.
It is known that the glass transition temperature of T is improved and a resin composition having excellent heat resistance and the like can be obtained (for example, U.S. Pat. No. 4,141,927, Japanese Patent Publication No. 3-58384, Journal of Applied Polymer Science). (J. Appl. Polym. Sci.) (199)
3) 48 pages 935 pages, polymer bulletin (Pol
ymer Bulletin) (1994) 33 volumes 1
Page 13, Macromolecules
les) (1995) Vol. 28, p. 2845). However, polyester resins having further excellent heat resistance are desired.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel resin composition obtained by mixing a polyester in which at least 80 mol% of constituent units is ethylene terephthalate and a specific polyimide. . A further object of the present invention is to provide at least 80 mol% of the structural units.
Is to provide a polyester composition obtained by mixing a polyester, which is ethylene terephthalate, with a specific polyimide, in which the heat resistance of the polyester is sufficiently improved, and a polyimide composition in which the moldability is greatly improved.
A further object of the present invention is to provide a polyester composition for a plastic hollow molded article having excellent heat resistance and suitable for applications such as beverage bottles and various containers.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by mixing a polyester having at least 80 mol% of constituent units of ethylene terephthalate with a specific polyimide, It has been found that the glass transition temperature of the polyester is significantly increased, the heat resistance is sufficiently improved, and the melt viscosity of the polyimide is reduced, so that the moldability is improved.

The present invention relates to a polyester (A) wherein at least 80 mol% of the structural units is ethylene terephthalate.
And the following equation (1)

[0007]

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(Where R ₁ is the above-mentioned polyester (A)
And C4 or more 1 which may contain a non-reactive substituent
The alicyclic alkylene and / or aliphatic alkylene having 2 or less, Ar is an aromatic residue having 6 to 13 carbon atoms which may contain a substituent that is non-reactive with the polyester (A). ), Wherein the weight ratio of (A) to (B) is 95: 5 to 5:95 with respect to the entire resin composition.
Is a resin composition falling within the range.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester (A) in the present invention is preferably polyethylene terephthalate in which 100 mol% of the structural units are ethylene terephthalate units. % As a copolymer component.

Examples of the acid component of such a copolymer include other aromatic dicarboxylic acids such as isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenyletherdicarboxylic acid, and diphenylsulfonedicarboxylic acid; Alicyclic dicarboxylic acids such as terephthalic acid and hexahydroisophthalic acid, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, etc., p-β-hydroxyethoxybenzoic acid, ε-oxycaproic acid, etc. Other bifunctional carboxylic acids, such as oxyacids. As the diol component, for example, trimethylene glycol,
Tetramethylene glycol, hexamethylene glycol, decamethylene glycol, neopentyl glycol, diethylene glycol, 1,1-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,
2-bis (4′-β-hydroxyphenyl) propane,
Bis (4′-β-hydroxyethoxyphenyl) sulfonic acid;

In the present invention, the polyester (A) is a polyester in which at least 80 mol% of the constituent units are ethylene terephthalate, but other polyesters may be contained within 20 mol% of the whole. Examples of other polyesters include polybutylene terephthalate and polyethylene naphthalate.

The polyester used in the present invention in a mixed solvent of tetrachloroethane: phenol = 4: 6 is used.
The intrinsic viscosity measured at 0 ° C. is 0.6-1.3 dl / g,
Preferably, it is 0.7 to 1.2 dl / g.

The polyimide (B) in the present invention comprises a repeating unit represented by the above formula (1), and the polyimide (B) is preferably amorphous from the viewpoint of solubility with the polyester (A). . However, even if a crystalline polyimide is not crystallized at the time of addition to the polyester, it can be dissolved in the polyester, but the crystalline polyimide is very hardly soluble in the polyester. The term “amorphous” as used herein refers to a material that does not show a clear melting point peak as measured by a differential scanning calorimeter (DSC), and is generally a transparent resin.

In the above formula (1), R ₁ has 4 carbon atoms which may contain a substituent which is non-reactive with the polyester (A).
It can be selected from 12 or less alicyclic alkylenes, aliphatic alkylenes, and combinations of two or more thereof, and specifically, those which form imide bonds derived from the following diamine compounds or diisocyanates are exemplified. can do. As the raw material compound, for example, isophoronediamine, cyclohexanediamine, 1,8-
Diamino-p-menthane, 2,2,4- or 2,4,
4-trimethylhexamethylenediamine, ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, octamethylenediamine, nonamethylenediamine,
Diamines such as decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and diisocyanate compounds such as isophorone diisocyanate. In this, R ₁ is isophoronediamine, 1,
8-Diamino-p-menthane, cyclohexanediamine, an alicyclic alkylene group derived from isophorone diisocyanate, an aliphatic alkylene group derived from 2,2,4- or 2,4,4-trimethylhexamethylenediamine is more preferable, Above all, the following formula (3)

[0015]

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Most preferred are groups derived from isophorone diamine and isophorone diisocyanate.

In the above formula (1), Ar is an aromatic residue having 6 to 13 carbon atoms which may contain a substituent which is non-reactive with the polyester (A). As Ar, for example,

[0018]

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Among them, a pyromellitic anhydride residue is most preferred.

The polyimide in the present invention can be produced by a generally known method. For example, (a) the above Ar
A dicarboxylic acid anhydride of the starting material to induce, or to heat ring-closure is first obtained polyamic acid and a diamine to induce the R _1, or acetic anhydride and pyridine, carbodiimide, the chemical dehydrating agent, such as triphenyl phosphite (B) The above-mentioned dicarboxylic anhydride and the above-mentioned diisocyanate for deriving R ₁ may be heated to perform decarboxylation to carry out polymerization. In addition, after (c) the dicarboxylic anhydride is converted into a partial ester or an all ester in the middle with a lower alcohol such as methanol or ethanol,
The cyclization reaction may be carried out after acid chloride with thionyl chloride, chlorine, phosphorus pentachloride or the like, and reaction with the corresponding diamine.

The molecular weight of the polyimide in the present invention is not particularly limited. When the amount of addition of the polyimide is small, it may be of a low molecular weight as long as the mechanical properties of the molded body are not impaired. . In general, when the polyimide is soluble in a phenol / tetrachloroethane mixed solvent (weight ratio 60/40), the intrinsic viscosity measured at 35 ° C. and a polymer concentration of 1.2 g / dl is 0.15 or more, preferably 0.25 or more. preferable. The upper limit is not particularly limited, but is practically about 5.

According to the present invention, a heat-resistant polyester composition containing polyester (A) as a main component and polyimide (B) as a minor component, and a molding containing polyester (A) as a minor component and polyimide as a main component. Provided is a polyimide composition having improved properties.

The mixing ratio of the polyester (A) to the polyimide (B) in the present invention is 95: 5 to 5:95 in terms of parts by weight based on 100 parts by weight of the whole resin composition. When the amount of the polyimide is less than 5 parts by weight, the effect of improving the glass transition temperature of the polyester composition is small, so that the effect of improving the heat resistance is also small. If the amount of the polyester is less than 5 parts by weight, the effect of improving the moldability of the polyimide is not sufficient.

In the polyester composition of the present invention, the heat resistance of which is improved by the addition of the polyimide is preferably 95: 5 to 60:40, more preferably 95: 5 to 70:30.

In the polyimide composition of the present invention, the moldability of which has been improved by the addition of polyester, the compounding ratio of polyester to polyimide is preferably 5:95 to 40:60, more preferably 5:95 to 30:70, and still more preferably. 5: 95-
20:80.

The method for producing the resin composition of the present invention includes:
A method of mixing the polyester (A) and the polyimide (B) using a biaxial extruder is preferably used.
The mixing temperature must be equal to or higher than the melting point of the polyester within a range that does not cause decomposition of the polymer. Mixing is substantially impossible below the melting point of the polyester. In addition, the temperature is preferably equal to or higher than the glass transition temperature of the polyimide to be added. Generally, 280-290 ° C is preferred.

Further, the resin composition of the present invention may contain various additives as necessary. Such additives include glass fiber, metal fiber, aramid fiber, ceramic fiber, potassium whisker titanate, carbon fiber, fibrous reinforcing agents such as asbestos, talc, calcium carbonate, mica, clay, titanium oxide, aluminum oxide, Various fillers such as glass flakes, milled fibers, metal flakes, metal powders, heat stabilizers such as phosphate esters and phosphites or oxidation stabilizers, light stabilizers, ultraviolet absorbers, lubricants, Examples include pigments, flame retardants, flame retardant aids, plasticizers, and crystal nucleating agents.

The polyester composition of the present invention containing the polyimide as a minor component can be formed into a hollow molded article by a general molding method such as injection blow molding, orientation blow, extrusion blow method and the like. The polyester composition is suitable for blow molding because the melt viscosity of the polyester increases with the addition of the polyimide, although it depends on the molecular weight of the polyimide to be added. As a suitable example of the orientation blow method, a polymer is made into an amorphous molded article (for example, 15 cm in length, 1 cm in inner diameter, and 1.4 cm in outer diameter) on a hollow cylindrical bottom having a suitable shape, and the glass transition of the polymer is carried out. Preheat to above the point (Tg) and increase the surface area of the container to about 1.5 to
A method of stretching to about 16 times is used. The heat treatment of the container can be appropriately performed.

The polyester molded hollow article as described above has a body haze of 3% or less and an average density of the body of 1.3.
4 to 1.37 g / cm ³ and an intrinsic viscosity of 0.6 to 1.0
It is preferably dl / g.

According to the present invention, the hollow molded article comprising the above polyester composition can be used for various uses, for example, juices, soft drinks, carbonated drinks, alcoholic beverages, detergents, seasonings,
It can be used as a container for oil, cosmetics, etc. Moreover, after the used container is collected and washed, the contents can be refilled and reused.

[0031]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the examples. In the examples, "parts" means "parts by weight". In the examples, the intrinsic viscosity of the polymer was determined from the value measured at 35 ° C. in a phenol / tetrachloroethane mixed solvent (weight ratio 60/40).

[Synthesis of polyimide (PIPM)] N-methyl-2-pyrrolidone 2000 ml in a nitrogen atmosphere
131.5 g of isophorone diisocyanate was charged therein, and 129.0 g of pyromellitic anhydride was added to this solution at room temperature, and then the temperature was gradually increased to generate carbon dioxide. After heating at 180 ° C. for 5 hours, the generation of carbon dioxide stopped. After the polymer solution was developed in water and sufficiently washed, the obtained polymer was dried. The intrinsic viscosity of the polymer is 0.5
0 (dl / g). Hereinafter, this polymer is referred to as PIP
Call it M.

[Examples 1 and 2] PE having an intrinsic viscosity of 0.71
Add a predetermined amount of PIPM to T100
mφ co-rotating 2-axis extruder (Ikegai Iron Works Co., Ltd.)
And melt discharge and kneading under the conditions of a polymer temperature of 290 ° C. and an average residence time of about 20 minutes using a PCM 30). The polymer thus obtained was heated at a rate of 20 ° C./min by a differential scanning calorimeter (DSC) and then melted at + 30 ° C.
After the temperature was raised to 200 ° C., the sample was taken out, rapidly cooled with dry ice, and then heated again at 20 ° C./min to determine the glass transition temperature. Addition of PIPM to PET significantly improved the glass transition temperature. The results are shown in Table 1.

[Comparative Example 1] Polyethylene terephthalate (PET) having an intrinsic viscosity of 1.01 was used in the same manner as in Examples 1 and 2 by using a 30 mm φ co-rotating biaxial extruder (PCM30, manufactured by Ikegai Iron Works Co., Ltd.) , Polymer temperature 29
The mixture was melt-kneaded at 0 ° C. for an average residence time of about 20 minutes, and the glass transition temperature was determined in the same manner as in Examples 1 and 2.

[Reference Example 1] Instead of PIPM, ULT
EM1000 (manufactured by General Electric) was melt-kneaded in the same manner as in Examples 1 and 2. As shown in Table 1, ULTEM
The increase in glass transition temperature due to the addition of 1000
Was less than when.

[0036]

[Table 1]

Example 3, Comparative Example 2 Intrinsic viscosity 1.01
Was added to 90 parts of the above-mentioned PIPM, and the polymer kneaded well at 330 ° C. was extruded from a hole having a diameter of 0.5 mm with a flow tester to obtain a thread-like sample. However, P with no added PET
Extrusion was not possible with the IPM-only polymer under the same conditions.

Example 4 PET8 having an intrinsic viscosity of 1.01
After adding 20 parts of PIPM to 0 parts and melting in the same manner as in Example 1, what was discharged from the discharge port of the above-described twin screw extruder was quenched with cooling water, and the diameter and the length were substantially reduced with a cutter. The chip was cut to 3 mm. The glass transition temperature of the obtained chip was 72 ° C. After hot-drying the chip at 160 ° C. for 5 hours, the cylinder set temperature was set to 2 using an M-100DM injection molding machine manufactured by Meiki Seisakusho.
The preform was obtained by injection molding in a mold cooled to 75 ° C. with cooling water at 10 ° C. This preform has a cylindrical body having an outer diameter of 22 to 24 mm, a thickness of 3.5 mm, and a total length of 150 mm, and has a bottom with one end, and is a substantially amorphous colorless and transparent molded body. there were.

This bottomed preform is heated at 100 to 130 ° C.
Stretch in the axial direction in the bottle-shaped mold at
g / cm ² , expanded laterally with nitrogen gas, with a body outer diameter of 82 mm, a total height of 280 mm, and an internal volume of 1450-1550.
ml bottles were molded.

The thus obtained bottle was filled with hot water at 75 ° C., allowed to cool at room temperature, and the volume change before and after filling with hot water was measured. The mouth of the bottle was cut, immersed in hot water at 75 ° C. for 1 minute, and the change in the inner diameter of the mouth before and after the treatment was measured.

Next, the heat resistance and the glass transition temperature of the polymer of the bottle thus obtained were determined using the bottle thus produced. The performance of the obtained bottle is shown in Table 2 below. The amount added in the table is the PIP in the total polymer.
Shows the weight percent of M. By containing PIPM, as in Comparative Example 3 below, the glass transition temperature was improved as compared with PET itself, and the volume shrinkage and the inner diameter shrinkage were reduced, and the heat resistance was greatly improved. The performance of the obtained bottle is shown in Table 2 below.

[0042]

[Table 2]

Comparative Example 3 PET having an intrinsic viscosity of 1.01 was melt-kneaded in the same manner as in Example 4, and formed into chips after forming into chips. The performance of the obtained bottle is shown in Table 2 above.

[0044]

According to the present invention, a heat-resistant polyester composition whose glass transition temperature is greatly improved by mixing a polyester having at least 80 mol% of constituent units of polyethylene terephthalate and a specific polyimide, or By adding the polyester, a polyimide composition having greatly improved moldability can be obtained. According to the present invention, it has become possible to obtain a polyester composition for a hollow molded article having excellent heat resistance.

Claims (3)

[Claims] 1. A polyester (A) in which at least 80 mol% of constituent units is ethylene terephthalate, and a compound represented by the following formula (1): (In the above formula (1), R ₁ has 4 carbon atoms which may contain a substituent which is non-reactive with the polyester (A).
An alicyclic alkylene and / or an aliphatic alkylene of 12 or less, and Ar is the above-mentioned polyester (A)
And 6 or more carbon atoms which may contain a non-reactive substituent
3 or less aromatic residues. A) a resin composition comprising a polyimide (B) comprising a repeating unit represented by the following formula: wherein the ratio of (A) and (B) is 95: 5 to 5:95 by weight with respect to the entire resin composition. Resin composition in the range. 2. The resin composition according to claim 1, wherein the polyimide (B) is amorphous. 3. The polyimide (B) is represented by the following formula (2): The resin composition according to claim 1, comprising a repeating unit represented by the formula: