JPH11335469A - Resin molded material, stretched molded material and film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester resin molded material, stretched and molded material, film, etc., eliminating defects caused by using a polyester resin as a raw material, excellent in transparency, mechanical strength and heat resistance, having a good molding property and suitably utilized for a bottle, film, etc. SOLUTION: This resin molded material is obtained by mixing two kinds of the same or different kinds of polyester resins having >=0.2 and <=1.2 intrinsic viscosities, and >=0.1 and <=1.0 difference in the intrinsic viscosities, and melt- molding the mixture. It is desirable that at least one kind of the polyester resin is a polyethylene-2,6-naphthalate and to mix >=10 wt.% and <=70 wt.% polyester resin having a lower intrinsic viscosity between the above polyester resins.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molded product, a stretch molded product, and a film obtained by melt-molding a polyester resin, and more particularly to a molded product having excellent transparency, mechanical strength and heat resistance. The present invention relates to a biaxially stretched polyester film having good processability.

[0002]

2. Description of the Related Art Polyester resins are excellent in mechanical strength, chemical stability, transparency, electrical properties, etc.
Since it is inexpensive, it is widely used for parts such as automobiles and electric appliances, food and beverage containers, clothing and industrial fibers, packaging, magnetic tape, and photographic films.

[0003] In particular, vinyl chloride resins and polyolefin resins have been used in bottles and laminate films for eating and drinking, but there are no problems such as residual monomers and harmful additives.
Polyester resins excellent in hygiene and safety have been widely used in recent years.

[0004] Polyethylene terephthalate (PET) has been most frequently used as a film resin for the above-mentioned food applications. However, when PET is used in applications requiring hot filling, high-temperature sterilization, or gas barrier properties, the heat resistance and gas barrier properties are not sufficient.

On the other hand, as a resin having excellent heat resistance and gas barrier properties, polyethylene-2,6-naphthalate (PE) is used.
N) is known and its application to bottles and films has been proposed, but has the disadvantage of high cost and poor transparency and moldability.

[0006]

An object of the present invention is to eliminate the drawbacks of using the above polyester resin as a raw material, and to improve transparency and transparency.
An object of the present invention is to provide a polyester resin molded article, a stretch molded article, and a film which are excellent in mechanical strength and heat resistance and have good moldability and can be suitably used for bottles, films and the like.

[0007]

The inventors of the present invention have conducted intensive studies for this purpose, and as a result, by mixing a polyester resin having a specific intrinsic viscosity, it has excellent transparency, mechanical strength, and gas barrier properties, and has a high moldability. It has been found that a resin molded product, a stretch molded product and a biaxially stretched film having good properties can be obtained, and the present invention has been achieved.

The object of the present invention is to provide two kinds of the same or different kinds having an intrinsic viscosity of 1.0.2 or more and 1.2 or less and having a difference of intrinsic viscosity of 0.1 or more and 1.0 or less. A resin molded article characterized by mixing and melt-molding a polyester resin,

[0009] 2. At least one of the polyester resins
2. The resin molded article according to the above 1, wherein the seed is polyethylene-2,6-naphthalate.

[0010] 3. 10% by weight or more and 70% by weight of the polyester resin having a low intrinsic viscosity.
The resin molded article according to 1 or 2 above, which is mixed below,

4. The polyester resin having a low intrinsic viscosity, wherein the intrinsic viscosity of the polyester resin is 0.5 or less.
The resin molded article according to any one of to 3,

5. The resin molded article according to any one of the above items 1 to 4, wherein both of the polyester resins are polyethylene-2,6-naphthalate.

6. A stretch-formed product, which is obtained by stretching the mixed resin according to any one of the above 1 to 5,

7. A film, which is obtained by biaxially stretching the mixed resin according to any one of the above 1 to 5,
Is achieved by each of

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below.
The polyester resin constituting the resin molded product of the present invention has two or more kinds of the same or different kinds having an intrinsic viscosity of 0.2 or more and 1.2 or less and a difference of intrinsic viscosity of 0.1 or more and 1.0 or less. The polyester resin is not particularly limited as long as it is a mixture of the above polyester resins, but is preferably a melt-moldable polyester resin containing a dicarboxylic acid component and a diol component as main components.

The main dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 2,6-
Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenyletherdicarboxylic acid, diphenylethanedicarboxylic acid,
Examples thereof include cyclohexanedicarboxylic acid, diphenyldicarboxylic acid, diphenylthioetherdicarboxylic acid, diphenylketonedicarboxylic acid, and phenylindanedicarboxylic acid.

The diol component includes ethylene glycol, propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis (4-hydroxyethoxyphenyl) propane. , Bis (4-hydroxyphenyl) sulfone, bisphenol full orange hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone,
Cyclohexanediol and the like can be mentioned.

Among the polyesters containing these as main components, from the viewpoint of transparency, mechanical strength, dimensional stability, etc., terephthalic acid and / or 2,6-naphthalenedicarboxylic acid and diol components as dicarboxylic acid components. And polyesters containing ethylene glycol and / or 1,4-cyclohexanedimethanol as main constituents.

Among them, polyesters containing polyethylene terephthalate or polyethylene-2,6-naphthalate as main constituents, copolymerized polyesters composed of terephthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol, and diesters of these polyesters Polyesters whose main constituent is a mixture of more than one species are preferred. Particularly preferred is a polyester containing polyethylene-2,6-naphthalate as a main component.

The intrinsic viscosity of the polyester to be mixed according to the present invention is preferably from 0.2 to 1.2. Intrinsic viscosity is 0.2
If it is less than 1, the degree of polymerization is low, so that the film formability and strength are not improved. From the above viewpoint,
More preferred intrinsic viscosity of the polyester of the present invention is 0.3
It is 1.0 or less.

The difference in the intrinsic viscosity of the polyester to be mixed is preferably as large as possible in order to enhance the effect of the present invention. However, in order to increase the intrinsic viscosity difference, one intrinsic viscosity is increased. From the upper limit, there is necessarily a limit to that range. From the above viewpoint, the difference in intrinsic viscosity of the polyester of the present invention is preferably from 0.1 to 1.0, and more preferably from 0.2 to 0.7.

The mixing ratio of the polyester resin of the present invention is preferably 10% by weight or more and 70% by weight or less, more preferably 10% by weight or more and 5% by weight or less.
0% by weight or less. When the mixing ratio of the polyester resin having a low intrinsic viscosity is high, the effect of the present invention is reduced.

The polyester constituting the biaxially stretched polyester film of the present invention may be further copolymerized with other copolymer components as long as the effects of the present invention are not impaired. It may be.
Examples of these include the above-mentioned dicarboxylic acid component and diol component, and polyesters composed thereof.

In the polyester of the present invention, an aromatic dicarboxylic acid having a sulfonate group or an ester-forming derivative thereof, a dicarboxylic acid having a polyoxyalkylene group or an ester-forming derivative thereof have been used in order to prevent delamination during film formation. And a diol having a polyoxyalkylene group.

Among them, 5-sodium sulfoisophthalic acid, 2-sodium sulfoterephthalic acid, 4-sodium sulfophthalic acid, 4-sodium sulfo-2,6-naphthalenedicarboxylic acid are preferred in view of polymerization reactivity of polyester and transparency of film. Compounds obtained by substituting acids and their sodium with other metals (eg, potassium, lithium, etc.), ammonium salts, phosphonium salts and the like, or ester-forming derivatives thereof, polyethylene glycol, polytetramethylene glycol, polyethylene glycol-
Preference is given to polypropylene glycol copolymers and compounds which have been converted into carboxyl groups by oxidizing the hydroxy groups at both ends thereof. The proportion copolymerized for this purpose is preferably 0.1 to 10 mol% based on the functional dicarboxylic acid constituting the polyester.

For the purpose of improving heat resistance, a bisphenol compound and a compound having a naphthalene ring or a cyclohexane ring can be copolymerized. The copolymerization ratio is preferably from 1 to 20 mol% based on the functional dicarboxylic acid constituting the polyester.

The method for synthesizing the polyester of the present invention is not particularly limited, and it can be produced according to a conventionally known method for producing polyester. For example, a direct esterification method in which a dicarboxylic acid component is directly esterified with a diol component, first using a dialkyl ester as a dicarboxylic acid component, a transesterification reaction between the dicarboxylic acid component and a diol component, and heating this under reduced pressure. A transesterification method in which polymerization is performed by removing an excess diol component can be used. At this time, if necessary, a transesterification catalyst or a polymerization reaction catalyst may be used, or a heat stabilizer may be added.

In each step of the synthesis, an anti-coloring agent, an anti-oxidant, a crystal nucleating agent, a sliding agent, a stabilizer, an anti-blocking agent, an ultraviolet absorber, a viscosity regulator, a defoaming transparent agent, an antistatic One or two or more of various additives such as an agent, a pH adjuster, a dye, and a pigment may be added.

[0029]

Next, the present invention will be described specifically with reference to examples. In the examples, the characteristic values were measured as follows.

Heat resistance (glass transition temperature Tg) 10 mg of a film or a bellet is applied at 300 cm / min.
Melt at 300 ° C. in a nitrogen stream of No. ³ and immediately quench in liquid nitrogen. The quenched sample was set on a differential scanning calorimeter (DSC8230, manufactured by Rigaku Corporation), and was set at 10 / min.
In a 0 ml nitrogen stream, the temperature was raised at a rate of 10 ° C. per minute,
Detect Tg. Tg was defined as the average value of the temperature at which the baseline began to be biased and the temperature at which it returned to the new baseline. In addition, the measurement start temperature is set at 100 from the measured Tg.
The temperature should be lower than ℃.

Transparency (film haze) Measured according to ASTM-DIO3-52.

Intrinsic Viscosity Films or pellets are combined with phenol and 1,1,
Mixed soot of 2,2-tetrachloroethane (weight ratio 60 /
40), dissolved in a concentration of 0.2 g / dl, 0.6 g / d
1, a solution of 1.0 g / dl is prepared, and the specific viscosity (η _SP ) at each concentration (C) is determined at 20 ° C. using an Ubbelohde viscometer. Then, η _SP / C is plotted against C, and the resulting direct tax is extrapolated to zero concentration. Ask for. The unit is indicated by dl / g.

Mechanical strength and formability (elastic modulus and rupture strength) A film was cut into a piece having a width of 10 mm and a length of 200 mm, conditioned at 23 ° C. and 55% RH for 12 hours, and then orientated. Kaku Tensilon (RTA-100)
, The distance between the chucks is 100 mm, and the pulling speed is 10
A tensile wiping test was performed at a rate of mm / min to determine the elastic modulus and the breaking strength. Here, the elastic modulus was used as a measure of mechanical strength, and the breaking strength was used as a measure of moldability. The smaller the breaking strength, the better the moldability.

A polyester resin was prepared as follows. (PET-A) 0.05 parts by weight of magnesium acetate hydrate was added as a transesterification catalyst to 100 parts by weight of dimethyl terephthalate and 65 parts by weight of ethylene glycol, and transesterification was performed according to a conventional method. 0.05 parts by weight of antimony trioxide and 0.03 parts by weight of trimethyl phosphate were added to the obtained product. Next, gradually raise the temperature,
The pressure was reduced, and polymerization was performed at 280 ° C. and 0.5 mmHg to obtain polyethylene terephthalate having an intrinsic viscosity of 0.50.

(PET-B) Polyethylene terephthalate having an intrinsic viscosity of 0.34 was obtained in the same manner as in PET-A.

(PET-C) PET-A at 130 ° C.
After pre-crystallization for a time, solid phase polymerization was performed at 210 ° C. under a nitrogen stream to obtain polyethylene terephthalate having an intrinsic viscosity of 0.80.

(PEN-A) To 122 parts by weight of 2,6-dimethylnaphthalate and 69 parts by weight of ethylene glycol, 0.05 part by weight of manganese acetate tetrahydrate was added as a transesterification catalyst, and a transesterification reaction was carried out according to a conventional method. went.
To the obtained product, 0.04 parts by weight of antimony trioxide,
0.03 parts by weight of trimethyl phosphate was added.
Then, gradually raise the temperature and reduce the pressure, 290 ° C., 0.5 mm
Polymerization with Hg, polyethylene having an intrinsic viscosity of 0.58
2,6-Naphthalate was obtained.

(PEN-B) Polyethylene-2,6-naphthalate having an intrinsic viscosity of 0.30 was obtained in the same manner as in PEN-A.

(PEN-C) PEN-A was heated at 130 ° C. for 2 hours.
After preliminarily crystallizing for 2 hours, solid phase polymerization was carried out at 215 ° C. under a nitrogen stream to obtain polyethylene-2,6-
Naphthalate was obtained.

(PEN-D) 100 parts by weight of dimethyl 2,6-naphthalenedicarboxylate, ethylene glycol 56
4.1 parts by weight (5 mol%) of 1,4-butanediol were added, and 0.1 part by weight of magnesium acetate hydrate was added as a transesterification catalyst, and transesterification was performed according to a conventional method. . 0.04 part by weight of antimony trioxide and 0.1 part by weight of trimethyl phosphate were added to the obtained product. Then, the temperature was gradually raised and reduced to 285.
Polymerization was conducted at 0.5 ° C and 0.5 mmHg to obtain a copolymerized polyester having an intrinsic viscosity of 0.40 and composed mainly of polyethylene-2,6-naphthalate.

Using the polyesters obtained as described above, biaxially stretched polyester films of Comparative Examples 1 to 3 and Inventions 1 to 6 were prepared as follows.

Comparative Example 1 PET-A pelletized product was vacuum-dried at 150 ° C. for 8 hours, melted and extruded from a T-die at 285 ° C. into a layer, and adhered to a 30 ° C. cooling drum while applying static electricity. After cooling and solidification, an unstretched film was obtained. This unstretched sheet was stretched 3.3 times in the machine direction at 80 ° C. using a roll-type longitudinal stretching machine. The obtained uniaxially stretched film is stretched by a tenter-type transverse stretching machine in a first stretching zone of 90 ° C. at 50% of the total transverse stretching ratio, and further in a second stretching zone of 100 ° C.
The film was stretched so that the total transverse stretching ratio became 3.3 times. Next, a pre-heat treatment was performed at 70 ° C. for 2 seconds, followed by heat setting at 150 ° C. in the first fixing zone for 5 seconds and heat setting at 220 ° C. in the second fixing zone for 15 seconds. Next, the film was cooled to room temperature over 60 seconds while being relaxed in the transverse direction by 5%, and the film was released from the clip and wound up to obtain a biaxially stretched film having a thickness of 50 μm.

Comparative Example 2 PEN-A was used instead of PET-A of Comparative Example 1,
Melt extrusion temperature 300 ° C, cooling drum temperature 50 ° C, longitudinal stretching temperature 135 ° C, first transverse stretching zone temperature 145 ° C, second transverse stretching zone temperature 155 ° C, pre-heat treatment temperature 100 ° C,
First fixed zone temperature 200 ° C, second fixed zone temperature 23
Except that the temperature was changed at 0 ° C., in the same manner as in Comparative Example 1,
A biaxially stretched film having a thickness of 50 μm was obtained.

Comparative Example 3 PET-A and PEN-A were blended by a tumbler type mixer so that the weight ratio was as shown in Table 1.
The film forming conditions were as follows: melt extrusion temperature 295 ° C, cooling drum temperature 45 ° C, longitudinal stretching temperature 110 ° C, first transverse stretching zone temperature 125 ° C, second transverse stretching zone temperature 135 ° C, pre-heat treatment temperature 85 ° C, first fixed. A biaxially stretched film having a thickness of 50 µm was obtained in the same manner as in Comparative Example 1, except that the zone temperature was changed to 180 ° C and the second fixed zone temperature was changed to 225 ° C.

Example 1 In place of PET-A and PEN-A of Comparative Example 3, PEN-A
C and Blend in the same manner except that PEN-B was used. The film formation conditions were the same as in Comparative Example 2.

Example 2 In place of PET-A and PEN-A of Comparative Example 3, PET-A
B, Blend in the same manner except that PET-C was used. The film forming conditions were the same as in Comparative Example 1.

Example 3 A blend was made in the same manner as in Comparative Example 3, except that PET-A was used instead of PET-A. The film formation conditions were the same as in Comparative Example 3.

Examples 4 to 7 Blends were produced in the same manner as in Comparative Example 3, except that PET-A and PEN-A were replaced with the two types of polyester resins shown in Table 1 and their blend ratios. The film formation conditions were the same as in Comparative Example 2. Table 1 shows the characteristic values of the properties of the obtained biaxially stretched polyester film.

[0049]

[Table 1]

As is evident from the above results, according to the present invention, transparency, heat resistance and mechanical strength are excellent, and moldability is improved.

[0051]

The polyester film of the present invention has heat resistance and gas barrier properties which are very suitable for use as a packaging material for food applications, and has excellent transparency, mechanical strength and moldability. It has the effect.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B29L 7:00 C08L 67:02 (72) Inventor Hidetoshi Eren 1 Sakuracho, Hino-shi, Tokyo Konica Corporation (72) Inventor Kenji Onuma 1st Konica Corporation, Hino-shi, Tokyo Konica Corporation (72) Inventor Ikuo Kurashi 1st Konica Corporation, Sakura-cho Hino-shi, Tokyo (72) Inventor Yumi Ito 4-1 Kanebocho, Hofu City, Yamaguchi Prefecture Inside Kanebo Gosen Co., Ltd. (72) Inventor Tetsutaro Hashimura 4-1 Kanebocho, Hofu City, Yamaguchi Prefecture Inside Kanebo Gosen Co., Ltd. (72) Masaki Yamamoto 4-1 Kanebocho, Hofu City, Yamaguchi Prefecture Kanebo Gosen Stock In company

Claims (7)

[Claims] 1. It has an intrinsic viscosity of 0.2 or more and 1.2 or less,
Further, a resin molded article characterized in that two kinds of the same or different polyester resins having a difference in intrinsic viscosity of 0.1 or more and 1.0 or less are mixed and melt-molded. 2. The resin molded article according to claim 1, wherein at least one of said polyester resins is polyethylene-2,6-naphthalate. 3. The resin molded article according to claim 1, wherein a polyester resin having a low intrinsic viscosity is mixed in an amount of 10% by weight to 70% by weight among the polyester resins. 4. The polyester resin having a low intrinsic viscosity has an intrinsic viscosity of 0.5 or less.
4. The resin molded article according to any one of 3. 5. The resin molded product according to claim 1, wherein both of the two polyester resins are polyethylene-2,6-naphthalate. 6. A stretch molded product obtained by stretching the mixed resin according to any one of claims 1 to 5. 7. A film obtained by biaxially stretching the mixed resin according to claim 1.